Patent Description:
It is known in horticulture to grow plants, usually crops, without soil, by using mineral nutrient solutions in an aqueous solvent, such methods are known as provide hydroponics. Plants may be grown with their roots exposed to a nutritious fluid or liquid. The roots of the plants may be physically supported by an inert medium.

Once such method known as Ebb and Flow (or flood drain) involves periodically filling or flooding a chamber or vessel in which plants are located with a nutrient rich solution (hydroponic solution) for a desired period of time and then subsequently draining the hydroponic solution from the chamber or vessel.

An object of the present invention is to provide a hydroponic apparatus which fills the chamber or vessel with a predefined volume of hydroponic solution during each fill phase of the hydroponic cycle.

It is another object of the invention to provide a simple apparatus capable of delivering the hydroponic solution and oxygen to the plant root zone.

<CIT> discloses a device for watering plants, by periodically inundating the same with a nutrient solution, the device comprises a trough, a working container for the nutrient solution, said container being connected to the trough with the aid of means for feeding in the solution for periodically inundating the trough and being linked to means for periodically injecting air. The device comprises an additional container for the nutrient solution, which container is fitted into the body of the device or next to the device. From below, the additional container has a neck in the form of at least one opening and/or pipe. A compressor is switched on with the aid of a timer. The problem addressed by the invention is that of lengthening the period of the self-acting, automatic operation of the device and increasing the compactness of the device.

The present invention seeks to provide an improvement in the field of hydroponic growing systems.

A first aspect of the invention provides a hydroponic apparatus for growing plants comprising a reservoir for a liquid and a growth vessel for a plant. A tank is disposed in the reservoir and is in fluidic communication with the reservoir and with the growth vessel. The tank is configured to be coupled to an air supply. The tank comprises an inlet valve, for allowing liquid in the reservoir to enter the tank, and an outlet valve, for allowing air in the tank to vent to atmosphere. The apparatus may comprise a controller for activating and deactivating the air supply.

Advantageously, the apparatus employs a single device to delivers both fluids, liquid and air, to the root zone, and negates the requirement for a pump or device dedicated to each fluid being delivered.

Further, there is no requirement to mount a liquid pump within the hydroponic solution or to pump the hydroponic solution through a liquid pump located externally of the reservoir.

Optionally, the air supply is an air pump.

Optionally, the air supply is an air compressor.

Optionally, the liquid is a nutrient rich aqueous solution.

Optionally, the outlet valve is pressure sensitive.

Optionally, the outlet valve is a pressure control valve.

Optionally, the outlet valve is adjustable.

Optionally, the apparatus comprises a first pipe connected to the air supply extends into the tank.

Optionally, the first pipe terminates with a diffuser.

Optionally, the first pipe terminates with an air stone.

Optionally, the first pipe comprises a check valve for inhibiting fluid flow towards the air supply.

Optionally, the growth vessel comprises a sump in which a drain is located.

Optionally, the apparatus comprises a fluid conduit extending between the growth vessel and the tank.

Optionally, the fluid conduit comprises a first port disposed in the tank.

Optionally, the first port is disposed proximate to a lowermost wall of the tank.

Optionally, the first port is located proximate the deepest region of the tank.

Optionally, the fluid conduit comprises a second port disposed in the growth vessel.

Optionally, the controller is a time activated switch.

A second aspect of the invention provides a method of use of a hydroponic apparatus for growing plants comprising: a reservoir comprising a liquid, a growth vessel comprising a plant being cultivated, and a tank disposed in the reservoir and in fluidic communication with the reservoir and with the growth vessel. The tank comprises an inlet valve, for allowing liquid in the reservoir to enter the tank, and an outlet valve, for allowing air in the tank to vent to atmosphere. The apparatus is coupled to an air supply. The method comprises charging the growth vessel with liquid from the tank by activating the air supply, supplying air to the tank and pressurising the tank. Liquid is forced the from the tank to enter the growth vessel. The method comprises discharging the growth vessel by deactivating the air supply and draining the liquid in the growth vessel back into the tank. The tank is vented to the atmosphere and the pressure in the tank is equalised with the liquid pressure in the reservoir.

Optionally, the further comprises filling the tank by;.

A third aspect of the invention provides a kit of parts for growing plants comprising:.

Optionally, the kit of parts further comprises a fluid conduit for coupling the outlet valve to the tank.

Optionally, the kit of parts further comprises a fluid conduit for coupling the tank to the growth vessel.

Optionally, the kit of parts further comprises an air supply.

Optionally, the kit of parts further comprises a fluid conduit for coupling an air supply to the tank.

Optionally, the kit of parts further comprises a controller for activating and deactivating the air supply.

Exemplary embodiments of the invention will now be described with reference to the accompanying drawings, in which:.

Detailed descriptions of specific embodiments of a hydroponic apparatus, components and methods are disclosed herein. It will be understood that the disclosed embodiments are merely examples of the way in which certain aspects of the invention can be implemented and do not represent an exhaustive list of all of the ways the invention may be embodied. As used herein, the word "exemplary" is used expansively to refer to embodiments that serve as illustrations, specimens, models, or patterns. Indeed, it will be understood that the hydroponic apparatus, components and methods described herein may be embodied in various and alternative forms. The Figures are not necessarily to scale and some features may be exaggerated or minimised to show details of particular components. Well-known components, materials or methods are not necessarily described in great detail in order to avoid obscuring the present disclosure. Any specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the invention.

Referring to <FIG>, there is shown a plan view of a hydroponic apparatus <NUM>. The apparatus <NUM> comprises a container forming a reservoir <NUM> having a lid, closure or support structure <NUM> capable of supporting a growth vessel <NUM> (along with the plant under cultivation and a predefined volume of a hydroponic solution HS, see <FIG>, and optionally a growth or support medium). A pot <NUM> may be disposed in the growth vessel <NUM>. The pot <NUM> may be removeable. The pot <NUM> is adapted to receive the plant or crop being cultivated, for example it may have apertures or openings to allow the passage of the hydroponic solution HS into and out of the interior of the pot <NUM>. The lid <NUM> may optionally close an upper end of the reservoir <NUM>, this may reduce evaporation of the hydroponic solution HS this may be advantageous where water supply is limited. The lid <NUM> may comprises an access <NUM> in the form of an opening or removable hatch. The access <NUM> may be useful for filling the reservoir with water or nutrients, measuring or monitoring the fluid level in the reservoir, and measuring characteristics of the hydroponic solution such as but not limited to nutrient level, oxygenation, or pH.

Optionally, the reservoir <NUM> may be substantially shaped as an octagonal prism, although other shapes may be employed for example but not limited to, cuboids, cylinders, hexagonal prisms. It will be appreciated that the side walls of the reservoir need not be vertical and the reservoir <NUM> may be an inverted square, hexagonal, octagonal or conical frustrum.

A tank <NUM> is disposed in the reservoir <NUM> and may be mounted on supports on an inner surface of a base wall of the container forming the reservoir <NUM>.

The tank <NUM> comprises an inlet valve Vi. The inlet valve Vi may be mounted in a lowermost wall of the tank <NUM>. The inlet valve Vi provides that fluid can flow to flow into the tank <NUM> from the reservoir <NUM>. The inlet valve Vi may allow fluid to flow into the tank <NUM> from the reservoir when the pressure within the tank is less than the pressure in the reservoir <NUM> at the depth of the inlet valve Vi. The inlet valve Vi may be passive.

In other embodiments the inlet valve Vi may be active and may be coupled to an actuator under the control of a controller, the controller may be coupled to one or more sensors, such as, but not limited, to pressure sensors. The controller may open or close the valve in dependence upon a measurement parameter being monitored by the one or more sensors.

A pressure control or pressure relief valve Vp is in communication with the tank <NUM> and may be located at an upper end of a fluid conduit <NUM> extending from an uppermost wall of the tank <NUM>. The pressure control valve Vp allows air in the tank <NUM> to be released during the drain phase of the operational cycle.

The tank <NUM> is in fluid communication with the growth vessel <NUM> via a second fluid conduit <NUM>. The second fluid conduit <NUM> comprises a first end or port EI providing an inlet/outlet disposed proximate the lowermost wall of the tank <NUM>. In this way, the tank <NUM> can be substantially emptied of hydroponic solution during the fill phase of the cycle.

The second fluid conduit <NUM> comprises a second end or port EO providing an inlet/outlet located in a lower region of the growth vessel <NUM>. The growth vessel <NUM> may comprise a well, sump or sink in a bottom wall thereof which may facilitate drainage of hydroponic solution back into the tank <NUM> during the drain period of the cycle.

The outlet end EO of the second fluid conduit <NUM> may comprises a cover, filter or guard to prevent or inhibit undesired particulate matter flowing in to the tank <NUM>, this may be further reduced by allow the outlet of the second fluid conduit <NUM> to stand proud of the surrounding region of the bottom wall of the growth vessel <NUM>. This may help reduce cleaning and maintenance due to blockages or restrictions in fluid flow or interference in valve operation by particulate matter.

Additionally, or alternatively, the cover may serve to provide a diffuser; diffusing fluid flowing out of the second fluid conduit <NUM>.

The tank <NUM> is in fluid communication with an air source in the form of air pump <NUM> via an air line <NUM> the air line <NUM> may comprise a pipe, hose or tube that may be flexible. Optionally, the air line comprises a check valve Vc to prevent flow of hydroponic solution from the tank <NUM> to the air pump <NUM>.

Alternatively, the air pump <NUM> may be disposed at an elevation above the maximum fluid level in the reservoir <NUM>, or at least a portion of the air line <NUM> may be routed above the maximum fluid level in the reservoir <NUM>.

The air line <NUM> may comprise a diffuser in the form of an air stone <NUM> at an outlet end located in the tank <NUM>. The air stone <NUM> may diffuse air as it flows into the tank <NUM>, it may also act as a check valve or fluid restrictor inhibiting flow of the hydroponic solution into the air line <NUM>.

In the illustrated embodiment, an air supply <NUM> takes the form of a pump or a compressor, it may be powered from mains electricity, a battery, a generator, one or more solar panel or wind turbines, combustion engine or other suitable power source.

In other embodiments, the air line <NUM> may be coupled to a tank of compressed air or a manual pump.

<FIG> illustrate stages of a fill and drain cycle of the growth vessel <NUM>.

<FIG> shows the apparatus <NUM> with a hydroponic solution HS disposed in the reservoir and in the tank <NUM>, the reservoir <NUM> can be filled via the access hatch, or may comprise a dedicated filling inlet in other embodiments. The air pump <NUM> is in an off or inactive state, that is to say air is not being supplied to the tank <NUM> via the air line <NUM>. The hydroponic solution HS enters the tank <NUM> via the inlet valve Vi since the pressure in the reservoir <NUM> is equal to the pressure in the tank <NUM>.

A fill phase of the cycle commences by changing the state of the air pump <NUM> to an on or active condition in which air AIR is supplied to the tank <NUM> via the air line <NUM>.

In <FIG>, the air pump <NUM> is in an on or active state, air AIR has been supplied to the tank <NUM> via the air line <NUM>. As the air AIR is pumped into the tank <NUM> the air AIR; being less dense than the hydroponic solution HS, rises to the top of the tank <NUM>. The pressure in the tank <NUM> increases. In doing so the hydroponic solution HS is displaced from the tank <NUM> through the second fluid conduit <NUM> into the growth vessel <NUM>.

In <FIG> the air pump <NUM> has continued to charge or fill the tank <NUM> with air AIR until the all the hydroponic solution HS has been raised into the growth vessel <NUM>, or at least until the hydroponic solution HS fluid level in the tank <NUM> is below the inlet end EI of the second fluid conduit <NUM>.

Optionally, the air pump <NUM> remains in the on state, air AIR continues to be pumped into the tank <NUM>. When the pressure in the tank <NUM> rises sufficiently air AIR escapes through the second fluid conduit <NUM> into the growth vessel <NUM> so as to aerate the hydroponic solution HS and the root zone of the plants being cultivated. The outlet valve Vp is configured to offer greater resistance for the air AIR to escape to the atmosphere than the second fluid conduit <NUM>. The air AIR pressure in the tank <NUM> is greater than the pressure of the hydroponic solution HS in the reservoir <NUM> at the depth of the inlet valve Vi. The inlet valve Vi is thus closed and prevents the hydroponic solution HS in the reservoir <NUM> entering the tank <NUM>.

The air pump <NUM> may be coupled to a controller or timer <NUM> which controls the length of time the air pump <NUM> is in the on condition. The timer <NUM> may be configured to allow the air pump <NUM> to supply air AIR to the tank <NUM> for a desired period after the tank <NUM> has been emptied of the hydroponic solution HS or the maximum fill level of the growth vessel <NUM> has been reached. The air AIR escapes the tank <NUM> via the second fluid conduit <NUM> into the growth vessel <NUM> whilst the pump <NUM> is active.

In some embodiments, the apparatus <NUM> may comprises one or more sensors and a controller coupled thereto which controls the operation of the air pump <NUM>. The sensors may detect fluid levels in the tank <NUM>, reservoir <NUM> or growth vessel <NUM>. The sensors may detect characteristics of the hydroponic solution HS such as but not limited to its oxygenation level. Based upon data received from the sensors the controller may determine when to shut the air pump <NUM>, for example, but not limited to, if sensor data indicates that oxygen level in the hydroponic solution HS is low the controller may allow the air pump <NUM> to run for an extended period. The controller may be coupled to other external devices or sensors such as light sources (growth lights) or light sensors, temperature or humidity sensors. The controller may adjust the fill / drain cycle in dependence upon information from the sensors to optimise growth of the plants, it may cease or reduce filling of the growth vessel when light levels in the growth environment are low or below a threshold value. The fill/drain cycle maybe adjusted in dependence upon the plant being cultivated; the controller may comprise one or more selectable pre-defined or user customisable programs. The controller may also allow remote monitoring or control of the apparatus <NUM>.

<FIG> illustrates the apparatus <NUM> during the drain phase of the cycle. The drain phase commences when the air pump <NUM> is returned to an off or inactive state.

The hydroponic solution HS in the growth vessel <NUM> returns to the tank <NUM>. Air AIR in the tank <NUM> initially escapes through the second fluid conduit <NUM> into the growth vessel <NUM> until the liquid level in the tank <NUM> rises to submerge the inlet end EI of the second fluid conduit <NUM>. Since the pressure in the tank <NUM> is lower than the pressure exerted by the fluid in the growth vessel <NUM> the hydroponic solution HS returns to the tank <NUM>. The pressure in the tank <NUM> is still sufficient to seal the inlet valve Vi, preventing ingress of liquid in the reservoir <NUM> into the tank <NUM>. The air AIR in the tank <NUM> is compressed towards the upper or top wall of the tank <NUM>. The pressure control valve Vp allows the air AIR in the tank <NUM> to escape to the atmosphere.

The pressure control valve Vp, in the illustrated embodiment is disposed in the reservoir <NUM> above the maximum fill level of the reservoir <NUM>. In other embodiments, the pressure control valve Vp may be disposed outside the reservoir <NUM>.

The pressure control valve Vp may be variable such that the rate at which the hydroponic solution HS returns to the tank <NUM> can be controlled or adjusted.

<FIG> illustrates the apparatus <NUM> during the drain phase, the hydroponic solution HS in the growth vessel has returned to the tank <NUM>. As the hydroponic solution HS returns under the force of gravity to the tank <NUM> the pressure in the tank reduces. Since the tank <NUM> is vented to atmospheric pressure, if the volume of water returning to the tank <NUM> is less than that which was pumped out the pressure in the tank <NUM> will fall below the pressure of the liquid in the reservoir <NUM> at the depth of the inlet valve Vi. Once the pressure of the fluids in the tank <NUM> is sufficiently low that the inlet valve Vi will open to allow hydroponic solution HS from the reservoir to enter the tank <NUM>, air AIR in the tank <NUM> will be vented to the atmosphere. The tank <NUM> is thus once again full of hydroponic solution HS, this controlling the volume of liquid available for the next fill phase. Any loss of hydroponic fluid that occurred during the fill phase (for example by absorption into the plant roots or support medium or evaporation to the atmosphere) is replaced from the reservoir <NUM>.

The volume of the tank <NUM> may be less than the volume of the growth vessel <NUM>. The volume of the tank <NUM> may be selected so as to avoid or mitigate against overfilling the growth vessel. The volume of the tank <NUM> may be selected so to avoid or mitigate filling the growth vessel beyond the root zone of the plant under cultivation. The volume of liquid delivered to the growth vessel <NUM> may be adjusted by adjusting the depth of penetration of the second fluid conduit <NUM> in to the tank <NUM>. The liquid delivery volume may reduce by raising the first end or port EI to space it further from the bottom wall of the tank <NUM>. The second fluid conduit <NUM> may be provided with an indicia, graduations or hatch markings to facilitate adjustment of the liquid delivery volume.

In those embodiments employing a pot <NUM>, in which the plant is disposed, the pot <NUM> may be selected to be of suitable size to accommodate the plant, the pot <NUM> may be changed or replaced as the plant grows. The liquid delivery volume may be adjusted in dependence upon the pot <NUM> dimensions, plant size or variety or environmental conditions.

In the illustrated embodiment the second fluid conduit <NUM> passes through the top wall of the tank <NUM>, in other embodiments the second fluid conduit <NUM> may enter the tank <NUM> through side wall or the bottom wall of the tank <NUM>. In some embodiments the tank <NUM> may comprise a hatch or resealable closure for gaining access to an interior of the tank for example to facilitate cleaning of the interior. The second fluid conduit <NUM> pass into the tank <NUM> through closure so as to be removeable with the closure for maintenance and cleaning.

It can also be appreciated that various changes may be made within the scope of the present invention. For example, the size and shape of the growth vessel, tank and/or reservoir may be adjusted. The apparatus <NUM> may comprise two or more growth vessels in fluidic communication with the reservoir; each may be individually coupled to the reservoir in parallel with each other. In other embodiments two or more growth vessels in fluidic communication with the reservoir and each other in series, a first vessel may be filled from the tank, subsequent vessels may be gravity fed from a preceding vessel in the series. The reservoir may comprise two or more tanks, each of the tanks may be coupled to a respective growth vessel or may be coupled to a common growth vessel. The apparatus <NUM> may comprise a plurality of air supplies or pumps, each may be coupled to a respective tank or to a common tank. In embodiments, having two or more tanks the tanks may be in fluidic communication with each other.

Whilst the apparatus <NUM> is configured to deliver a pre-defined volume of liquid to the growth chamber the growth chamber may be provided with an overflow mechanism in the event of a malfunction such as but not limited to valve failure.

The controller may also be in communication with one or more fault detection sensors which indicate the apparatus <NUM> needs attention, maintenance or repair. Such sensors may include, but not limited to, pressure or air flow sensors for detecting low air supply from the air pump, tank or other air supply or for detecting valve failure or compromise.

The controller may also comprise or be coupled to a communication device for informing an operator of the condition of the apparatus <NUM>, such device may take the form of one or more light or LED's, a monitor or screen or other visual display, modem, network interface (wired or wireless), Bluetooth or other radio communications device.

The apparatus <NUM> may be modular in construction and may be readily assembled, dismantled, upgraded or modified as required. The fluid pipes or conduits, fittings or connectors may be of push type or compression type such that no, or only basic tools, are required to assemble the apparatus <NUM>. In this way the apparatus <NUM> may be readily dismantled for maintenance or cleaning. Components of the apparatus <NUM> may be readily interchanged, for example to increase or decrease the size of the tank or the volume of liquid a given tanks delivers. A growth vessel <NUM> or pot <NUM> of a suitable size may be mounted to the apparatus <NUM> in dependence of the plant's requirements.

Claim 1:
A hydroponic apparatus (<NUM>) for growing plants, comprising a reservoir (<NUM>) for a liquid (HS) and a growth vessel (<NUM>) for a plant, wherein the hydroponic apparatus (<NUM>) further comprises a tank (<NUM>) disposed in the reservoir (<NUM>) and in fluidic communication with the reservoir (<NUM>) and with the growth vessel (<NUM>), wherein the tank (<NUM>) is configured and arranged to be coupled to an air supply (<NUM>), and wherein the tank (<NUM>) comprises an outlet valve (Vp), for allowing air (Air) in the tank (<NUM>) to vent to atmosphere, characterised in that the tank (<NUM>) comprises an inlet valve (Vi), for allowing liquid (HS) in the reservoir (<NUM>) to enter the tank (<NUM>).