WO2005033580A1

WO2005033580A1 - Lighting system with movable lighting, as well as a combination of at least two lighting systems with movable lighting, as well as a mehod for the cultivation of a crop

Info

Publication number: WO2005033580A1
Application number: PCT/NL2004/000710
Authority: WO
Inventors: Teunis Cornelis Van Den Dool
Original assignee: Hortilux Schréder B.V.
Priority date: 2003-10-08
Filing date: 2004-10-08
Publication date: 2005-04-14
Also published as: EP1671062A1; NL1024482C2

Abstract

The present invention relates to a lighting system with movable lighting (1) for illuminating a crop, comprising; - a support section (2) that is made up of individual pieces of section (36, 37, 38, 39) that are connected to one another such that they can be uncoupled; - a runner section (3) that can be moved with respect to the support section; - bearing means (4) for supporting the runner section on bearings in the support section; - drive means (5) for driving the runner section; - lighting that is connected to the runner section; - fixing means (6) for fixing the lighting to the runner section; - electrical cabling (7), wherein the runner section has an elongated part extending in the direction of movement thereof, provided with bearing means in at least two places located some distance apart in the direction of movement, and wherein the lighting comprises at least two lamps (20) located some distance apart, and wherein the runner section is made up of individual pieces of section (40, 41, 42) that are connected to one another in the direction of movement such that they can be uncoupled. The invention furthermore relates to a combination of at least two lighting systems with movable lighting and also relates to a method for the cultivation of crop.

Description

Lighting system with movable lighting, as well as a combination of at least two lighting systems with movable lighting, as well as a method for the cultivation of a crop

The present invention relates to a lighting system with movable lighting, as well as a combination of at least two lighting systems with movable lighting, as well as a method for the cultivation of a crop, wherein the crop is illuminated by the lighting system with movable lighting or by the combination of at least two lighting systems with movable lighting. Application of the invention will be mainly in greenhouse horticulture where lighting systems with movable lighting are becoming increasingly important because of the energy and cost savings to be made. The lighting system with movable lighting according to the invention comprises; a support section that is made up of individual pieces of section that are connected to one another such that they can be uncoupled; a runner section that can be moved with respect to the support section; - bearing means for supporting the runner section on bearings in the support section; drive means for driving the runner section; lighting that is connected to the runner section; fixing means for fixing the lighting to the runner section; electrical cabling, wherein the runner section has an elongated part extending in the direction of movement thereof, provided with bearing means in at least two places located some distance apart in the direction of movement, and wherein the lighting comprises at least two lamps located some distance apart. Such lighting systems are known in the literature, such as from International Patent Application WO 99/64786. The runner section in this known lighting system with movable lighting comprises a trolley or a motor housing, to which one or more lamps are connected. A disadvantage of this known installation is that only a limited number of lamps can be fixed to the trolley. This number is even further restricted if an electric motor is also provided on the trolley. It is therefore an aim of the invention to provide a lighting system with movable lighting that is flexible to a high degree as far as the number of lamps that are connected to the runner section is concerned and as far as the mutual distribution of the lamps over the length of the runner section is concerned. The invention makes this possible by providing a lighting system with movable lighting, as specified in the second paragraph, wherein the runner section is made up of individual pieces of section that are connected to one another in the direction of movement such that they can be uncoupled. As a result it is possible to make the runner section any desired length, which is restricted only by the length of the support section, and the number of lamps can be increased as desired. The distribution of the lamps over the runner section can also be easily adjusted, hi the case of the lighting system from WO 99/64786 additional trolleys must be attached to the support section if it is desired to increase the number of lamps. US Patent US 5 993 030 discloses a lighting system with movable lighting wherein a runner section is indeed made up of individual pieces of section, but wherein the pieces of section are connected to one another transversely to the direction of movement thereof. The disadvantage of this construction is that at least two support sections positioned some distance apart are needed in order to be able to move the runner section with respect thereto, h the case of the lighting system according to the invention the longitudinal directions of the support section and the runner section are the same as one another and the length of the row of lamps that are mounted on the runner section is restricted only by the length of the support section. According to the invention it is advantageous if the lighting comprises at least eight lamps located some distance apart, hi view of the conventional dimensions of a horticultural greenhouse, this number of lamps will be sufficient to illuminate a crop over the complete length of the greenhouse with adequate light intensity and adequate alternation between light and dark periods. In a preferred embodiment of the lighting system with movable lighting the drive means comprise an electric motor, wherein the electric motor is fixed to the support section. The advantage of this is that the electric motor does not constitute any hindrance for lamps that are connected to the runner section, as far as both space and weight are concerned. Moreover, if the electric motor is sufficiently powerful, it is possible to be able to move the complete runner section with only one electric motor. In an advantageous embodiment of the lighting system with movable lighting the drive means comprise a chain and the runner section has a U-section part, wherein the chain is provided in the U-section part and wherein the U-section part has two enclosing limbs for at least partially closing off an opening in the U-section part. With this embodiment the chain can take both pushing and pulling forces. Moreover, the chain cannot be pulled around a drive body, such as a sprocket. Because any chain that is generally commercially available can be used for the chain, tin^'s offers a less expensive solution than the use of a special gear rack for the drive. hi a preferred embodiment of the lighting system with movable lighting the runner section and the support section are each made up of individual pieces of section that are connected to one another such that they can be uncoupled. By this means any desired length of the lighting system can be set by appropriate choice of the number of pieces of section and the length of the individual pieces of section can remain restricted. hi another preferred embodiment of the present invention each lamp comprises: - a reflector for reflecting light and/or; a gas discharge lamp that is coupled to an ignitor for regulating the amperage through the gas discharge lamp. Gas discharge lamps are commonly used in greenhouse horticulture because of the favourable light technology characteristics as far as the growth of plants and crop are concerned. In tins case it is customary to use a reflector for as optimum as possible distribution of light. In another preferred embodiment of the lighting system with movable lighting the directions in which two lamps are connected to the runner section are either essentially the same as one another or essentially differ from one another by 180°. Including the ignitor and the reflectors, the lamps have an elongated shape. Because of the connection of the electrical cabling and the load of the lamp on the support section, in practice the longitudinal direction of the lamps and the runner section will be coincident. The advantage of being able to attach the lamps to the runner section in two different directions is that the obstruction as a consequence of the space that is taken up by, for example, the ignitor is partially reduced. By mounting two lamps in directions that differ from one another by 180° the lamps can be positioned closer together, hi this case the two reflectors of the lamps are adjacent to one another. According to the invention it is advantageous if the fixing means comprise a bracket section, wherein the one end of the bracket section can be accommodated in a recess in the runner section and another end can be accommodated in a recess in the lamp. Such an embodiment of the fixing means has the advantage that a lamp can be fixed to the runner section easily and quickly. h a particular embodiment the bracket section comprises two bracket plates provided with thickenings, which drop into the recesses, and adjustment means, wherein the adjustment means are provided in order to vary the distance between the bracket plates when the bracket section is in the fitted position. By means of this measure it is possible first to place the bracket section in a recess in the runner section or a recess in a lamp, where the two bracket plates are in contact with one another, so as then, with the aid of the adjustment means, to increase the distance between the bracket plates such that the thickenings on the bracket plates clamp firmly in the recesses. h a preferred embodiment of the lighting system with movable lighting, at least one cable duct is provided for at least partially enclosing the electrical cabling on the runner section, wherein the at least one cable duct on one side, which runs essentially parallel to the longitudinal direction of the runner section, is connected to the runner section in a hinged manner such that it can be uncoupled and on an opposing side is connected to the runner section by a snap-fit joint such that it can be uncoupled. The advantage of this embodiment is, on the one hand, that it is easy to fit the cable duct by means of the hinged joint and, on the other hand, that it is easy to open and to close the cable duct by means of the snap-fit joint. hi another preferred embodiment of the lighting system with movable lighting the bearing means comprise running wheels, wherein the running wheels protrude beyond one end of the runner section. As a result of this arrangement any differences in sagging between the support section and the runner section are offset, hi the case of too small a clearance between the two sections the top of the runner section would otherwise, specifically, be able to nib against the inside of the support section. According to the invention it is advantageous if the support section is suspended using a cable, the length of the cable being adjustable. The advantage here is that the height at which the lamps are suspended above the crop can be adapted to the growth stage of the crop. In a preferred embodiment of the present invention the at least two lamps are provided a distance of at least 140 cm apart. With such a mutual spacing sufficient light above the crop can be generated with the conventional lamps. The present invention furthermore relates to a combination comprising at least two lighting systems with movable lighting for increasing the surface area to be illuminated, wherein the lighting systems are provided either essentially parallel or essentially in the extension of one another and wherein the operation of the drive means and the operation of the lamps is integrated in a control unit provided with a microprocessor for adjusting the lighting to that desired. Use of such a combination is advantageous in particular when crop with a relatively large surface area has to be illuminated, where for reasons of efficiency and ease of operation it is advantageous if the operation of the drive means and the operation of the lamps of the individual lighting systems is provided in a control unit. Moreover, it can be the case that the surface to be illuminated comprises crop in various stages of growth, as a result of which the one lighting system must be controlled differently to the other lighting system. These differences can consist in a different (maximum) light intensity or a different alternation between light and dark. The present invention furthermore relates to a method for the cultivation of a crop, wherein the crop is provided in a greenhouse and the crop is essentially illuminated from above, h a first embodiment of this method optimum lighting for the crop to be cultivated is set with the aid of the operation of the drive means and the operation of the lamps and the distribution of the lamps over the length of the runner section. In a second embodiment of this method optimum lighting for the crop to be cultivated is set with the aid of the control unit for the combination described above and the distribution of the lamps over the lengths of the runner sections. It can be the case, for example, that the surface area that can be covered by the lighting system at a certain point in time is greater than the total surface area of the crop to be illuminated or that the surface area to be illuminated comprises crop in different stages of growth. The method described above makes it possible to adjust for this by adjusting the distribution of the lamps over the length of the runner section and/or the operation of the drive means and the lamps. In the case of several lighting systems working together, the use of a control unit for centralised control with this method offers an advantage with regard to the ease of operation. The present invention will be explained with reference to the following description of the appended figures. The figures show a preferred embodiment of the invention, other embodiments that fall within the scope of the invention also being possible, in which: Fig. la shows a cross-section of a support section with linking elements with a runner section at the location of bearing means, with a cable duct in the open position connected to the runner section and with fixing means connected to the runner section; Fig. lb shows a cross-section of a support section without a linking element to a runner section at the location of the bearing means with a cable duct in the closed position connected to the runner section and with fixing means connected to the runner section; Fig. 2 shows a perspective, partially exploded view of a runner section and a support section, with a cable duct connected to the runner section and fixing means and with a linking element connected to the support section; Fig. 3 shows a side view of a mid section of the lighting system with movable lighting; Fig. 4 shows a side view of an end portion of the lighting system with movable lighting. With reference to Figs 1 and 2 it is clear how a runner section 3 is moveable in a support section 2, where bearing means 4 are provided for supporting the runner section in bearings in the support section. Furthermore, the figures show fixing means 6, which preferably comprise two bracket plates 25 and adjusting means 26. The bracket plates 25 are provided at opposing ends with thickenings 28, which can be accommodated in a recess 29 in the runner section and can also be accommodated in a corresponding recess in a lamp (not shown). The purpose of the adjusting means 26 is to vary the distance between the bracket plates 25 in the fitted position. By increasing this distance the bracket plates will become clamped in the recesses in the runner section 3 and a lamp, respectively. It is also conceivable that the fixing means consist of an undivided bracket section. Figs 1 and 2 show a preferred embodiment of the drive means 5, which comprise a chain 8 that is provided in a LT-section part 9. The U-section part 9 has two enclosing limbs that close off, or at least partially close off, an opening 11 in the U-section part, so that the chain 8 cannot move upwards out of the runner section. As a result it is possible that the chain is able to take both pushing and pulling forces. Any chain that fits in the U-section part 9 can be used for the chain. A slot 33 is shown in Fig. 2, the slot being intended for interaction with a sprocket (not shown), which extends through the slot and engages on the chain 8. A standard electric motor 13, which is shown in Fig. 4, is used to drive the sprocket and the chain. By making the housing of the sprocket butt up to the slot 33, both the chain 8 and the sprocket can remain largely dust- and dirt-free. Although Fig. 2 shows a single support section and a single runner section, in practice use will be made of individual pieces of section that can be connected to one another such that they can be uncoupled. These pieces of section (36, 37, 38, 39, 40, 41, 42) are included in Figures 3 and 4. The individual pieces of section can be connected to one another in a conventional manner. With this arrangement the runner section is preferably joined by coupling strips 16. The support section is preferably connected by so- called clamp shell parts, which substantially encloses the pieces of support section to be connected over a certain length on both sides of the join. After the clamp shell parts have been fitted on the support section, a certain distance remains at the top of the two clamp shell parts. The two clamp shell parts are then screwed together with the aid of holes 58 using conventional means, the pieces of support section to be connected being firmly clamped inside. For additional safety the two pieces of support section to be connected could optionally be joined with a coupling plate before fitting the clamp shell parts. For this purpose the coupling plate is provided with projections that interact with holes that are provided in the two pieces of support section. The bearing means preferably comprise running wheels 43 that are joined to the runner section in pairs opposite one another. The running wheels are distributed at regular intervals over the length of a runner section, for example with a mutual spacing of 190 centimetres. In practice, the running wheels will be made of steel, but a steel core with a plastic covering, such as a nylon covering, is also possible. The functioning of the cable duct 27 will become clear looking at Fig. la and Fig. lb. The cable duct 27 serves to support the electrical cabling 7 along the major part of the length of the lighting system, which will become clear below when discussing Figures 3 and 4. When fitting the cable duct 27 this is first placed over a curved edge 35 of the runner section, as a result of which a hinged, releasable joint 30 between the cable duct 27 and the runner section 3 is produced. The electrical cabling - which is not shown in Figs 1 and 2 - is then placed in the cable duct 27 and the cable duct is snapped into place over a protrusion 32 on the runner section with the aid of a recess 31 in the cable duct. With this arrangement the interacting recess 31 and protrusion 32 are made such that this snap-fit joint can easily be uncoupled. Now referring to Fig. 3 and Fig. 4 it becomes clear how the lighting system with movable lighting 1 is fitted in a greenhouse. In this operation the support section 2 is preferably fixed to a roof truss 46 above a cultivation surface in a horticultural greenhouse. A conventional fixing cable 47, such as a steel cable, which, for example, is attached to holes in the clamp shell parts 17, is used for this puipose. Preferably, the length of the fixing cable 47 is adjustable in height so that the height of the lamps above the crop can be varied. This can be achieved, for example, by using one or more pulleys that are fixed to the roof truss (not shown). Furthermore, it can be seen in Figures 3 and 4 that the support section 2 consists of separate pieces of section 36, 37, 38, 39 and that the runner section 3 consists of separate pieces of section 40, 41, 42. The separate pieces of section will usually be aluminium extruded sections. A typical length of the runner section is 6 metres per piece of section and typical lengths of the support section are 5, S or 9 metres per piece of section. It will be immediately apparent from Figures 3 and 4 that the separate pieces of section are connected to one another in the direction of movement of the runner section. The positioning of the individual running wheels 43, which are distributed a regular distance apart along the runner section, is indicated with the aid of a broken line in Figures 3 and 4. Furthermore, the location of the slot 33 in the support section 2 is shown by a broken line in Fig. 4. This slot 33 is coincident with the housing 14 of a sprocket, which is driven by an electric motor 13. The electric motor 13 is preferably fixed to the top of the support section. This measure is also conceivable with any arbitrary other type of drive for the runner section. Preferably, the housing of the sprocket and the electric motor completely closes off the slot 33. Fig. 3 shows a number of cable ducts 27 that largely enclose the electrical cabling 7. The cable duct is interrupted wherever a cable is fed to a lamp and wherever fixing means are fitted between runner section 3 and a lamp 20. The electrical cabling 7 is provided immovably in the cable duct 27, even when the runner section is moved. Fig. 3 furthermore shows by broken lines two lamps 20 provided with reflectors 23 for reflecting the light. Gas discharge lamps, such as, for example, a so-called 600 watt SON lamp, are preferably used in horticulture. Such lamps are provided with an ignitor 21 for regulating the amperage tlirough the lamp. However, other lamps such as incandescent lamps and fluorescent lamps can also be used in the lighting system in question. The two lamps 20 in Fig. 3 are angled at 180° with respect to one another. This has the advantage that, in view of the hindrance caused by the ignitor 21, the lamps can be positioned closer together. Of course, it is also possible to fix the lamps in the same direction with respect to the runner section, h practice between ten and twenty-seven lamps will be fixed to one continuous runner section. A typical distance between two adjacent lamps - taken between the centres of the lamps themselves - is 160 centimetres. If the lamps have been angled at 180° with respect to one another this distance is approximately 40 centimetres. Preferably the mutual spacing is at least 140 centimetres. A coupling strip 16 for the link between two pieces of runner section 40, 41 is shown by a broken line in Fig. 3. Fig. 4 shows an end portion of the lighting system with movable lighting 1. The electrical cabling mns from a final cable duct 27 via cable loops 49 to the end of the support section, the cabling being supported by trolleys 48. Preferably, the trolleys 48 have a profile corresponding to that of the runner section 3 and the trolleys 48 are mounted on bearings with four running wheels 43 (two on each side of the runner section). From one end of the support section 2 the electrical cabling 7 mns on to a control unit 50. h another embodiment it is also possible that the cabling is ran to a connection point at mains voltage. To prevent undesired swaying one end of the support section 2 is connected to a solid wall 51 or an outside wall section of a greenhouse. If the height of the fixing wire 47 is adjustable, one end of the support section can be slid along a guide rail (not shown). An undesired peak in the amount of light at the section of crop that is immediately below a return point for a lamp can be partially avoided by making the runner section temporarily move more rapidly at the time when the direction is reversed. The method for the cultivation of a crop according to the invention is put into practice as follows. Starting from a specific type of crop and a specific crop surface area that it is desired to illuminate, the desired number of lamps are connected to the runner section. If it is desired either to expand the crop surface area or to increase the light intensity by moving a larger number of lamps more rapidly over the crop, the length of the runner section can easily be extended by coupling supplementary pieces of section. Conversely, a number of pieces of section can also be uncoupled, for example when less light is needed or it is temporarily necessary to illuminate a smaller surface area. As already previously pointed out, the electric motor 13 is preferably provided on the top of the support section, irrespective of the type of drive that is used. If each runner section is provided with a chain that is driven by a sprocket it is advantageously possible in the case of several runner sections positioned in parallel to couple the individual sprockets to a common shaft, winch shaft can be driven by a single electric motor. Such an electric motor can, for example, be provided on the middle support section or, for example, can be provided on the ceiling section of the greenhouse such as roof tmss 46. In addition to the advantage of a reduced restriction in the space available for the lamps and the cabling, the provision of the electric motor on the support section or on a roof truss instead of on the runner section has the advantage that less weight is placed on the runner section. The abovementioned embodiments merely relate to preferred embodiments and serve for illustration of the invention. The scope of the invention is deteπnined solely by the appended claims. The abovementioned measures can advantageously also be used in any arbitrary combination. If applicable, measures that have been mentioned above only in combination can also be used individually. For example, the cable duct can also be omitted from the preferred embodiment shown. Furthermore, the electric motor can also advantageously be provided on the support section in the case of a type of drive other than the chain in the runner section as shown in the figures, which is driven by a sprocket.

Claims

1. Lighting system with movable lighting (1) for illuminating a crop, comprising; a support section (2) that is made up of individual pieces of section (36, 37, 38, 39) that are connected to one another such that they can be uncoupled; a runner section (3) that can be moved with respect to the support section; bearing means (4) for supporting the runner section on bearings in the support section; drive means (5) for driving the runner section; - lighting that is connected to the runner section; fixing means (6) for fixing the lighting to the runner section; electrical cabling (7), wherein the runner section has an elongated part extending in the direction of movement thereof, provided with bearing means in at least two places located some distance apart in the direction of movement, and wherein the lighting comprises at least two lamps (20) located some distance apart, characterised in that the runner section is made up of individual pieces of section (40, 41, 42) that are connected to one another in the direction of movement such that they can be uncoupled.

2. Lighting system with movable lighting (1) according to Claim 1, characterised in that the lighting comprises at least eight lamps located some distance apart.

3. Lighting system with movable lighting (1) according to Claim 1 or 2, characterised in that the drive means (5) comprise an electric motor (13), wherein the electric motor is fixed to the support section (2).

4. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that the drive means (5) comprise a chain (8) and the runner section (3) has a U-section part (9), wherein the chain is provided in the U-section part and wherein the U-section part (9) has two enclosing limbs (10) for at least partially closing off an opening (11) in the U-section part.

5. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that each lamp (20) comprises: a reflector (23) for reflecting light and/or; a gas discharge lamp that is coupled to an ignitor (21) for regulating the amperage through the gas discharge lamp.

6. Lighting system with movable lighting (1) according to Claim 5, characterised in that the directions in which two lamps (20) are connected to the runner section are either essentially the same as one another or essentially differ from one another by 180 degrees.

7. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that the fixing means (6) comprise a bracket section, wherein the one end of the bracket section can be accommodated in a recess (29) in the runner section (3) and another end can be accommodated in a recess in the lamp (20).

8. Lighting system with movable lighting (1) according to Claim 7, characterised in that the bracket section comprises two bracket plates (25) provided with thickenings (28) at opposing ends, which drop into the recesses (29), and adjustment means (26), wherein the adjustment means are provided in order to vary the distance between the bracket plates when the bracket section is in the fitted position.

9. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that at least one cable duct (27) for at least partially enclosing the electrical cabling (7) is provided on the runner section (3), wherein the at least one cable duct on one side, which mns essentially parallel to the longitudinal direction of the runner section, is connected to the runner section in a hinged manner such that it can be uncoupled and on an opposing side is connected to the runner section by a snap-fit joint such that it can be uncoupled.

10. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that the bearing means (4) comprise miming wheels (43), wherein the running wheels protmde beyond one end of the runner section.

11. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that the support section is suspended using a cable (47), the length of the cable being adjustable.

12. Lighting system with movable lighting (1) according to one of the preceding claims, characterised in that the lamps (20) are provided a distance of at least 140 centimetres apart.

13. Combination comprising at least two lighting systems with movable lighting (1) for increasing the surface area to be illuminated according to one of the preceding claims, wherein the lighting systems are provided either essentially parallel or essentially in the extension of one another and wherein the operation of the drive means (5) and the operation of the lamps (20) is integrated in a control unit provided with a microprocessor for adjusting the lighting to that desired.

14. Method for the cultivation of a crop, wherein the crop is provided in a greenhouse and the crop is essentially illuminated from above using the lighting system with movable lighting (1) according to one of Claims 1 - 12, wherein optimum lighting for the crop to be cultivated is set with the aid of the operation of the drive means (5) and the operation of the lamps (20) and the distribution of the lamps over the length of the runner section, wherein this distribution is adapted to the crop by coupling or uncoupling one or more pieces of section to or from the runner section.