NL2020665B1 - Air distribution conduit - Google Patents

Abstract

An air distribution conduit (1) for use in a greenhouse defined by an elongated lower end (2) of an elongated cultivation gutter (3) and by an elongated flexible sheet (4) having two elongated side ends (5,6) which elongated side ends (5,6) are connected to the elongated cultivation gutter (3) and wherein the conduit (1) is provided with multiple openings (12,19) along its length fluidly connecting the interior (13) of the conduit (1) with the exterior (14) of the conduit (1).

Description

Patent center

The Netherlands (2?) Application number: 2020665 © Application submitted: March 26, 2018

Θ 2020665

B1 PATENT @ Int. Cl .:

A01G 9/24 (2018.01) A01G 9/04 (2019.01)

Application registered: (73) Patent holder (s): October 2, 2019 VAN DER HOEVEN HORTICULTURAL PROJECTS B.V. in Den Hoorn. (43) Application published: (72) Inventor (s): (47) Patent granted: Vincent Martijn Kickert in The Hague. October 2, 2019 (45) Patent issued: (74) Agent: October 3, 2019 ir. M. Cramwinckel in Steenwijk.

(54) AIR DISTRIBUTION CONDUIT (57) An air distribution conduit (1) for use in a greenhouse defined by an elongated lower end (2) or an elongated cultivation gutter (3) and by an elongated flexible sheet (4) having two elongated side ends (5.6) which elongated side ends (5.6) are connected to the elongated cultivation gutter (3) and being the conduit (1) is provided with multiple openings (12.19) along its length fluidly connecting the interior (13) or the conduit (1) with the exterior (14) or the conduit (1).

NL B1 2020665

This patent has been granted regardless of the attached result of the research into the state of the art and written opinion. The patent corresponds to the documents originally submitted.

AIR DISTRIBUTION CONDUIT

The invention is directed to an air distribution conduit for use in a greenhouse.

Such air distribution conduits for use in a greenhouse are described in EP1923614.

This publication describes such conduits as tubes provided with opening suspended below cultivation gutters or cultivation drainpipes by means of multiple hooks connected to a carrier provided along the upper end of the tubes. Such air distribution tubes aim to distribute air to the cultivation positioned above the tubes. A disadvantage of using such tubes is that their installation below the cultivation drainpipes is very labor intensive. Especially when one realizes that the suspension hooks are spaced at about 0.3 m, that single tubes may have a length of more than 120 meters and that in a single greenhouse sometimes up to 300 parallel positioned tubes are installed. A next disadvantage is that the air exiting the opening in the upflow part of the tube will have a directional component in the direction of the tube. This is not desired because undesired air circulation within the greenhouse may result.

This problem of undesired air flow within the greenhouse is addressed in Tae Young Kim et ai., Improving the distribution of temperature by a double air duct in the air-heated plastic greenhouse, Journal of bio-environment control ISSN: 1229-4675, full . 13, no.3 January 1, 2004 (2004-01-01), pages 162-166. This journal article describes an air distribution tube for use in a greenhouse where the tube is provided with an inner tube. Within the inner tube air travels from a fan to a dead end. Along its route air passes the tube wall to flow into an annular space between inner and outer tube. In this way the varying air velocity within the inner tube is converted into a substantial constant pressure in the annular space. This results in that air is substantially equally discharged along the length of the outer tube. W02011028100 also describe an air distribution tube provided with an inner tube for use in a greenhouse. This double ducting effect for equal discharge or air was well known and described for example in GB1242500, FR2713317 and US3824909.

W02011 / 071511 describe a conduit consisting of an inner tube within an outer tube. The resulting annular space is divided into multiple compartments. The air flows from the inner tube through opening to the various compartments and from these compartments into the greenhouse. A complex arrangement or opening seems to be required to achieve an equal distribution or air along the length of the tube. A further disadvantage of this tube is the complexity which results from the use of the multiple compartments.

The present invention aims to provide an air distribution conduit which can be easily installed and preferably provides a substantial equal distribution or air along its length.

This is achieved through the following air distribution conduit. An air distribution conduit for use in a greenhouse defined by an elongated lower end of an elongated cultivation gutter and by an elongated flexible sheet having two elongated side ends which elongated side ends are connected to the elongated cultivation gutter and the conduit is provided with multiple opening along its length fluidly connecting the interior of the conduit with the exterior of the conduit.

Applicants found that using an elongated flexible sheet and a simpler connection can be made with the elongated cultivation gutter as compared to the tube suspended below the cultivation gutter. In the novel conduit part of the conduit is provided by the lower end of the cultivation gutter itself and part is provided by the elongated sheet. This not only omits the need to manufacture a tube provided with carrier means to suspend the tube. It also allows one to use a simple sheet which can be attached to an easier method to the cultivation gutter. Further advantages will be described when discussing the preferred figures and figures.

In this description of the invention terms such as upper, lower, above and below are used to describe the invention. These terms describe the invention as it is most likely to be applied in a greenhouse. The terms are in no way used to limit the scope of protection.

The flexible sheet may be made of a flexible material. Preferably this material is a polymer, such as for example polypropylene.

The sheet may be connected directly to the elongated cultivation gutter or via an intermediate part. The sheet is preferably connected to cultivation gutter or to an intermediate connecting part in a manner which allows simple installation of the sheet. In one preferred embodiment the connection is by means of an elongated rope or present at the elongated edge of the sheet. Such a rope can slide within a guiding profile strip as present on the cultivation gutter or on the optional intermediate part. Such a connection between a sheet provided with a rope and a guiding profile strip may for example be performed as is known for connecting the luff of a main sail to a guiding profile strip as present on a mast of a sailing vessel. The rope may be made by folding the end of the sheet creating a thicker end of the sheet. Alternatively, the rope may be an actual rope which is connected to the side of the sheet by example sewing, gluing or welding. The elongated ends of the sheet may also be connected to an intermediate part by clamping the sheet between two interlocking parts or the intermediate part or cultivation gutter.

The sheet may be provided with opening along its length. The multiple opening or the conduit will then include the multiple opening in the flexible sheet. Through this opening air as being transported through the conduit is discharged from the interior of the conduit to the exterior of the conduit. In combination or alternatively the multiple opening of the conduit may be present in the cultivation gutter itself or more preferably in the intermediate connecting part which connects the sheet with the cultivation gutter.

The air distribution conduit preferably discharges air along its length such that the amount of discharged air is equally distributed along its length and the direction of the discharged air as it flows upwardly along the cultivation is a substantial vertical flow. The air distribution conduits are suitably closed or substantially closed at a downstream end and connected to an air displacement means, like a fan, at its upstream end. This results in that the air velocity will decrease along the length of the conduit and the static air pressure will increase. If no special measures are tasks more air will exit the downstream opening in the conduit and the air discharged from the upstream opening will have a directional component resulting from the air direction within the conduit as for example explained by Figure 3 of GB1242500.

Preferably a tube within the conduit according to the invention is positioned to achieve a more equal air outflow along the length of the conduit. This tube would be connected to the air displacement means resulting in that air would travel via this inner tube to a space between the walls of the inner tube and the air distribution conduit and from there to the exterior of the air distribution conduit.

A disadvantage of such a tube within a conduit version is that the installation of the inner tube within the air distribution conduit is laborious. For this reason it is preferred to position a second conduit adjacent to the air distribution conduit according to the invention. This second conduit is preferably formed by a further elongated flexible sheet having two elongated side ends which elongated side ends are connected to the elongated cultivation gutter either directly or via the intermediate connecting part. The use of the flexible sheet is advantageous because they are simpler to manufacture than a tube. The two adjacent conduits will be fluidly connected to each other along their length through opening in one of the sheets. The air distribution conduit or the second conduit may be connected to the air displacement means as will be illustrated in the figures.

The cultivation gutter may consist of a central strip for supporting the cultivation and two lower positioned gutters to which water can flow from the higher positioned cultivation. The gutters suitably have an upwardly directed outer wall such that a channel results in which water may flow. The sheet or sheets may be connected directly to the cultivation gutter and more preferably to the outer wall of the gutter. The outer wall may be provided with a guiding profile strip for receiving the earlier referred to rope or the sheet. It may be envisaged that the upwardly directed outer wall has been extended with a downwardly directed flap which flap is provided with such a guiding profile strip. The flap itself may be provided with opening which may serve as the opening of the air distribution conduit connecting the interior of the conduit with the exterior of the conduit. These cultivation gutters are preferably made from plate metal and may be formed on-site from a single role of metal by means of roll forming.

Adding such a flap, guiding profile and opening to a cultivation gutter may be complex when the cultivation gutter is made by roll forming from a single role of metal. It may therefore be preferable to use an intermediate connecting part which is connected to each of the two gutters and more preferably to each outer upwardly directed gutter wall. The intermediate part may be provided with opening. Preferably the intermediate connecting part is provided with opening which results in a substantial perpendicular outflow direction of the air as it is discharged from the air distribution conduit into the greenhouse growing section. This may be achieved by providing multiple channels directed perpendicular to the flow direction of the air in the air distribution conduit and positioned along the length of the air distribution conduit. Preferably the intermediate connecting part is a hollow part provided with opening connecting the hollow space with the interior of the air distribution conduit and opening connecting the hollow space with the greenhouse growing section. This hollow space may level out some of the differences of the static pressure within the air distribution conduit resulting in a more equal outflow or air into the greenhouse growing section. Such a hollow intermediate connecting part may be made from two elongated parts, each made on site by means of roll forming, which parts may be connected by means of a clamping connection. In this clamping connection the sheet may be sandwiched by these two parts resulting in a connection between sheet and intermediate connecting part.

The air distribution conduits according to the invention are preferably used in a greenhouse. The invention is also directed to a greenhouse provided with these air distribution conduits. Preferably multiple parallel positioned air distributions conduits are present in such a greenhouse. The upflow end of the air distribution conduits may be positioned near one of the end or side walls of the greenhouse. More preferably the ends are fluidly connected to a corridor running along the side or end of the greenhouse. In such a corridor air from external the greenhouse, air from within the greenhouse and / or their mixtures may be optionally conditioned before the air is provided for the upflow end of the air distribution conduits. It may be just as possible that the upflow end of one group or parallel positioned air distribution is fluidly connected to one corridor at one side or end of the greenhouse and that another group is fluidly connected to a corridor at an opposite end or side wall of the greenhouse. Conditioning may include cooling, heating, humidifying or dehumidifying the air. Such air conditioning corridors are well known and described for example in EP1464219, WO2004032606, WO00076296, WO2015 / 012698 and WO2008002686.

The invention is illustrated by the following figures. Figure 1 shows a cross-sectional view AA 'or an air distribution conduit (1) shown in Figure 2. The conduit (1) is defined by the lower end (2) or an elongated cultivation gutter (3) and by an elongated flexible sheet (4). Sheet (4) has two elongated side ends (5.6) connected to the elongated cultivation gutter (3). The cultivation gutter (3) has a central strip (7) for supporting a cultivation (8) and two lower positioned gutters (9) at each side to which water can flow from the higher positioned cultivation (8). The gutters (9) have an upwardly directed outer wall (10) such that a channel results in which water may flow. The sheet (4) is connected directly to the upper end (11) or the outer wall (10) or the gutter (9). The outer wall is provided with a guiding profile strip at the upper end (11) for receiving a rope as provided at the ends (5.6) or the sheet (4) as shown in more detail in Figure 9A and Figure 10 for a two -sheet embodiment. The sheet (4) is provided with multiple openings (10) along its length fluidly connecting the interior (12) or the conduit (1) with the exterior (13) or the conduit (1).

Figure 2 shows the upflow part of conduit (1) or Figure 1 from aside. A conduit (1) in a typical greenhouse application will have a considerably longer length than in Figure 2. At the upflow end of conduit (1) a fan (15) is shown. This fan draws in air into the conduit (1). The air may be from the exterior of the greenhouse, recirculating air from within the greenhouse or mixtures of these air flows. The upflow ends of a multitude or parallel positioned conduits may be fluidly connected to a mixing corridor at a wall of the greenhouse where air from the exterior of the greenhouse, recirculating air from within the greenhouse or mixtures of these air flows can be fed to the multiple fans (15) as described for example in applicant's WO17176114.

Figure 3 shows a cross-sectional view AA 'or an air distribution conduit (1) shown in Figure 4. As in Figure 1 the conduit (1) is defined by the lower end (2) or an elongated cultivation gutter (3) and by an elongated flexible sheet (4). The sheet (4) is connected to the gutter (3) via an intermediate connecting part (18). Connecting part (18) as shown may be a folded metal strip provided with a row of opening (19) along its length. The upper part of the strip (18) is folded such that it can suspend from the upper end (11) or the outer wall (10) or the gutter (9). The lower end of the strip (18) may be provided with a guiding profile strip for receiving a rope as provided at the ends (5.6) or the sheet (4) as shown in more detail in Figure 9A and Figure 10 for a two-sheet embodiment.

Figure 4 shows the upflow part of conduit (1) or Figure 3 from aside.

Figure 5 shows a conduit (1) with an alternative intermediate connecting part (20).

This part (20) is provided with multiple outflow channels (21) which is directly the air in a perpendicular direction with respect to the air flow within the conduit (1) as shown in more detail in Figure 6. By choosing a sufficient length of these channels (21) relative to its crossflow area the air will have a substantial perpendicular direction when it is discharged to the exterior (14) or conduit (1). The part (20) has a folded upper end such that it can be suspended from the upper end (11) or the outer wall (10) or the gutter (9) and is provided with a guiding profile (22) for connection with the ends (5,6) or sheet (4).

Figure 7 shows a conduit (1) with an alternative intermediate connecting part (24).

The connecting part (24) is an elongated hollow part provided with opening (25) connecting the hollow space (26) with the interior (13) or the air distribution conduit (1) and opening (27) connecting the hollow space (26) with the greenhouse growing section on the exterior (14). This hollow space (26) levels out some of the differences of the static pressure within the air distribution conduit (1) resulting in a more equal outflow or air into the greenhouse growing section via opening (27). The connecting part (24) is suspended from the upper end (11) or the outer wall (10) or the gutter (9) by means of a bended section (28) at its upper end. At its lower end part (24) is provided with a guiding profile (29) for connection with the ends (5.6) or sheet (4).

Figure 8 shows an embodiment with adjacent to the air distribution conduit (1) a second conduit (30) is positioned according to the invention. This second conduit is formed by a further elongated flexible sheet (31) having two elongated side ends (32.33). The elongated side ends of sheet (31) are directly connected to the elongated cultivation gutter (9) in this figure. Two possible connections for detail B is shown in Figures 9 and 10. Alternatively a connecting part may be used. Upstream in conduit (1) a fan (15) is present. The conduit (1) is fluidly connected to conduit (30) by means of its opening (12) in sheet (4) along its length. Conduit (30) is fluidly connected to its exterior (34) by means of opening (35) along the length of sheet (31). Conduit (30) levels out some of the differences of the static pressure within the air distribution conduit (1) resulting in a more equal outflow or air into the greenhouse growing section via opening (35).

Figure 9A shows an example of how end (6) or sheet (4) and end (33) or sheet (31) are connected to the upper end (11) or the outer wall (10) or the gutter (9). End (6) is provided with a rope (36) which travels within guiding profile (37). End (33) is provided with a rope (38) which travels within a guiding profile (39).

Figure 10 shows another example of how end (6) or sheet (4) and end (33) or sheet (31) are connected to the upper end (11) or the outer wall (10) or the gutter (9). Ends (6) and (33) are connected to the same rope (40) which travels guiding profile (41).

The invention is thus also directed to an air distribution conduit on the exterior (14) or the conduit (1) a second flexible elongated sheet (31) having two elongated side ends (32.33) is connected via its elongated side ends ( 32.33) to the elongated cultivation gutter (4) Creating a second conduit (30) positioned substantially below the first conduit (1), including the opening (12) in the sheet (4) fluidly connect the interior (13) or the conduit (1) and the interior of the second conduit (30), provided the second sheet (31) is provided with opening (35) along its length fluidly connecting the interior of the second conduit (30) with the exterior (34) or second conduit (30) and being the interior (13) or conduit (1) is fluidly connected to an air displacement means (15) which air displacement means (15) in use supply a flow or air to one end of the conduit ( 1).

Figure 11 shows a conduit (1) as in Figure 3 where a second conduit (45) is positioned adjacent to conduit (1). A difference with the embodiment of Figure 8 is that the fan (15) is now positioned upstream conduit (45). The air flowing through conduit (45) can flow to conduit (1) via opening (46) as present along the length of sheet (4). Conduit (1) levels out some of the differences of the static pressure within the air distribution conduit (45) resulting in a more equal outflow or air into the greenhouse growing section via opening (35). Conduit (45) is formed by sheet (47) and by sheet (4). The ends (5.6) or sheet (4) and the ends (48.49) or sheet (47) are connected to the lower end or connecting part (18) via guiding profiles as shown before.

The invention is thus also directed to an air distribution conduit on the exterior of the conduit (1) a second flexible elongated sheet (47) having two elongated side ends (48.49) is connected via its elongated side ends (48.49 ) via a connecting part (18) to the elongated cultivation gutter (4) creating a second conduit (45) positioned substantially below the first conduit (1), provided sheet (4) is provided with opening (46) along its length fluidly connecting the interior (13) or conduit (1) with the interior of the second conduit (45) and being the interior of the second conduit (45) is fluidly connected to an air displacement means (15) which air displacement means (15) in use supply flow or air to one end of the conduit (45).

Claims (9)

CONCLUSIONS An air distribution line (1), for use in a greenhouse, defined by an elongated lower end (2) of an elongated culture trough (3) and by an elongated flexible sheet (4) with two elongated side ends (5, 6), wherein these elongated side ends (5, 6) are connected to the elongated culture trough (3), and wherein the conduit (1) is provided with a plurality of openings (12, 19, 21) along its length, which are a fluid form a connection between the interior (13) of the pipe (1) and the exterior (14) of the pipe (1). Air distribution line according to claim 1, wherein the sheet (4) is provided with openings (12) along its length, and wherein the plurality of openings of the line (1) the plurality of openings (12) in the flexible sheet (4) ) includes. Air distribution line according to one of claims 1 to 2, wherein the elongated side ends (5, 6) of the flexible sheet (4) are connected to the elongated culture trough (3) by means of a connecting part (18, 20, 24), wherein this part (18, 20, 24) is provided with openings (19, 21, 25), and wherein the plurality of openings of the conduit (1) the plurality of openings (19, 21, 25) of the connecting part (11). Air distribution line according to claim 3, wherein the connecting part (20) is provided with a plurality of outflow channels (21), the copies of which are in a direction perpendicular to the direction of air flow in the line (1). Air distribution line according to claim 3, wherein the connecting part (24) is an elongated hollow part which is provided with openings (25) which form a connection between the hollow space (26) and the interior (13) of the air distribution line (1), as well as openings (27) connecting the cavity (26) to the exterior (14) of the conduit (1). The air distribution conduit according to claim 2, wherein externally (14) of the conduit (1) a second flexible elongated sheet (31) with two elongated side ends (32, 33) is connected via the elongated side ends (32, 33) thereof with the elongated culture trough (4), thereby creating a second conduit (30) positioned substantially below the first conduit (1), the openings (12) in the sheet (4) forming a fluid connection between the interior ( 13) of the conduit (1) and the interior of the second conduit (30), the second sheet (31) having openings (35) along its length that form a fluid connection between the interior of the second conduit ( 30) and the exterior (34) of the second conduit (30), and wherein the interior (13) of the conduit (1) is fluidly connected to air displacement means (15), said air displacement means supplying an air flow to one end during use of the pipe (1). Air distribution line according to one of claims 3 to 5, wherein the outside (14) of the line (1) is provided with a second flexible elongated sheet (47) which comprises two elongated side ends (48, 49), said ends (20, 21) connect the sheet (47) via the connecting part (11, 20, 24) to the elongated culture trough (4) thereby creating a second conduit (45) positioned substantially below the first conduit (1), wherein the sheet (4) is provided with openings (46) along its length, which form a fluid communication between the interior (13) of conduit (1) and the interior of the second conduit (45), and wherein the interior of the second conduit (45) communicates with air displacement means (15), said air displacement means (15) supplying an air flow to an end of the second conduit (45) during use. Use of the air distribution line (1) according to one of claims 1 to 7, to distribute air in a greenhouse. A greenhouse provided with a plurality of parallel positioned air distribution ducts according to any one of claims 1 to 7, wherein its upstream end is fluidly connected to a passageway positioned at an end or side wall of the greenhouse. 1/6