Power distribution system comprising a track to which electrical components are connected

The invention relates to a kit of parts comprising DC, low voltage system of an elongated track and a plug. The elongated track has a first and a second end and comprises an elongated slot formed by a central groove with at least one shielded lateral groove, both grooves lying in a plane P. Typically two electric conductors are accommodated in said at least one lateral groove. A connector portion of the plug having a connector cross section which matches with a cross section of the slot. Both said slot cross section and connector cross section are asymmetrical with respect to a plane Q extending over the length axis perpendicular to plane P, and at least one of the slot cross section and connector cross section is mirror symmetrical with respect to said plane P. The symmetric and asymmetric requirements posed on both the cross section of the elongated track and the connector portion of the plug ensure that the connector portion only being insertable into the first end in the axial direction and, after a rotation of 180° over its connector axis, only being insertable in the axial direction into the second end of said track, with maintenance of the correct polarity The invention further relates to a plug suitable for use in the kit of parts according to the invention.

CROSS-REFERENCE TO PRIOR APPLICATIONS

This application is the U.S. National Phase application under 35 U.S.C. § 371 of International Application No. PCT/EP2019/062446, filed on May 15, 2019, which claims the benefit of European Patent Application No. 18172568.0, filed on May 16, 2018. These applications are hereby incorporated by reference herein.

FIELD OF THE INVENTION

The invention relates to a kit of parts comprising an elongated track and a plug. The invention further relates to a plug of said kit of parts.

BACKGROUND OF THE INVENTION

In particular such a kit of parts is related to an electrical power track system for lighting purposes, such as a minitrack system being of direct current (DC) thus having a specific polarity, and being of low voltage, e.g. 24 Volt or 12 Volt. These tracks find wide application for distribution of power, for example in domestic appliances, such as a room of a house, or in professional environments such as offices and/or shop windows. Via plugs, the track can be connected to power means for providing power to a single module or a plurality of energy consuming modules mountable on said track. Often the provision of a plurality of plugs is done to provide all of the plurality of mounted modules with power. However, this involves both the risk of a power overload of the track with subsequent risk of overheating and early failure, and involves the risk of connecting plugs with reversed polarity for said DC tracks. GB2149230A discloses a mains voltage electric power distribution system comprising a track and a plug in which the abovementioned problems of overload and connecting with reversed polarity are counteracted. When transformed to low voltage systems, this known power distribution system has yet the disadvantage that only one plug can be provided which often is insufficient to provide all of the plurality of mounted modules with enough power.

SUMMARY OF THE INVENTION

It is an object of the invention to provide, as a power distribution system, a kit of parts comprising a track and plug of the type as described in the opening paragraph and in which at least one of the disadvantages is counteracted. Thereto the kit of parts comprises an elongated track and a plug:

the elongated track extending along a length axis in an axial direction, having a first and a second end and comprising an elongated slot formed by a central groove with at least one shielded lateral groove, said slot having a slot cross section and an open side opposite a bottom surface,

said central groove and lateral groove extend next to each other in a plane P,

at least two electric conductors are accommodated in said at least one lateral groove,

said slot, open side, central groove, at least one lateral groove and electric conductors extend in axial direction essentially from the first end to the second end,

a connector portion of the plug extending along a connector axis, having a first and a second, oppositely arranged main surface, and having a connector cross section which matches with the slot cross section,

wherein both said slot cross section and connector cross section are asymmetrical with respect to a plane Q extending over the length axis perpendicular to plane P, and at least the slot cross section is mirror symmetrical with respect to said plane P, and

the slot comprises at least one off-center located profiled structure extending in axial direction over essentially the whole length over the bottom surface of the slot, and each main surface has a corresponding inversed profiled structure provided on the first and second main surface in mutually mirrored position with respect to plane P.

The slot cross section defines a key function for connectable elements to ensure correct polarity for both plugs and for modules such as lighting modules such as lamp units and/or sensors etc. The symmetric and asymmetric requirements posed on both the cross section of the elongated track and the connector portion of the plug ensure that the connector portion only being insertable into the first end in the axial direction. To switch the plug from the first end to the second end, it needs to be inserted from the opposite direction into the slot of the elongated track and thereto needs to be rotated over 180° over a normal axis perpendicular to plane P. If the elongated track and the connector portion of the plug would be symmetrical with respect to plane Q, the plug could be inserted with the wrong polarization into the slot. Thereto, both the track and the connector portion are asymmetrical with respect to plane Q, typically parts of the connector portion that match with the profile of the slot and are used for blocking or allowing insertion of the connector portion in the slot are symmetrical with respect to plane P so that after a rotation of 180° over its connector axis only being insertable in the axial direction into the second end of said track with the correct polarity. Hence, no mirror plugs are needed for connection of a plugs to both ends of the track, but this is thus attained by a single shape of the plug. Furthermore, the dimensions of the plug, and/or locations of electrical contacts on the plug with respect to the locations of the electrical conductors in the elongated track counteract that the plug can be inserted via the openside into the elongated track and electrically connected to the electric conductors of the elongated track, for example in that the connector portion is too large to be inserted into the slot via the open side of the slot.

It is further noted that the mirror symmetry need not to be exact for the whole connector portion, but only for critical parts thereof, i.e. it only needs to be sufficient to block the possibility to connect the plugs and modules in reverse polarity and yet enable insertion of the connector portion into either end of the track with the correct polarity. Furthermore asymmetric patterns or a mount feature may be provided on one or both of the main surfaces of the connector portion, for example for easy mounting of add-ons like an adaptable driver, sensor, and antenna for sending receiving (internet, communication, radio, Global Positioning System GPS)) signals or a light emitting diode (LED) light source or indicator, rendering the connector portion to be asymmetric with respect to plane P. Typically, but not necessarily, two electric conductors are used in the DC, low voltage elongated track according to the invention.

Often in known systems the plug comprises both a male and a female connector portion which enables multiple stacking of plugs onto each other and hence that multiple plugs are connectable to the elongated track via a single end of the elongated track, involving the subsequent risk too much power is connected to the elongated track and overload of the elongated track. To counteract that too much power is connectable to the elongated track via the plugs, the kit of parts may have the feature that the plug comprises only one connector portion.

The kit of parts may have the feature that the at least one shielded lateral groove has a lip extending over the lateral groove, said at least two electric current conductors being either embedded in said lip or embedded in a portion of said bottom surface opposite said lip, said connector having on each main surface one pair of electrical contacts which are mutually arranged in mirror symmetry with respect to plane P. In particular it is thus attained that electrical contact is made with the electric conductors in the lateral groove upon insertion into either end, but that in inserted position of the plug in the elongated track, the non-used pair of electrical contacts of the plug are shielded by the connector portion itself from unintentional touching by users.

As an alternative configuration to the at least two electric conductors being provided in a single lateral groove, the kit of parts may have the feature that the at least one shielded groove comprises a shielded lateral groove on either side of the central groove, each groove accommodating a respective one of the at least two electric current conductors. The grooves are then located relatively remote from each other which reduces the risk on short circuiting.

The kit of parts may have the feature that the connector portion comprises electrical contacts located at opposite lateral sides for electrical contacting in inserted portion to a respective electric conductor provided in a respective side walls of each lateral groove. Thus the number of electrical contacts on the plug can be limited to only one pair rendering it relatively cheap and of simple construction.

The kit of parts thus has the feature that the slot comprises at least one off-center located profiled structure extending in axial direction over essentially the whole length over the bottom surface of the slot, and each main surface has a corresponding inversed profiled structure provided on the first and second main surface in mutually mirrored position with respect to plane P. Such profiled structure is a simple and convenient means for providing the slot and connector portion with the required asymmetric for ensuring mounting of the plugs and/or modules with the correct polarity. Typically the profiled structure is at least one of a protruding rib, protruding step, indented slit and recessed step. Such profiled structures are relatively easy and cheaply manufacturable, for example via an extrusion process. Preferably, is symmetrical with respect to plane P for features of the connector cross section which are critical for a mutual match with the inverse features of the track.

The kit of parts may have the feature that the connector portion is located on the plug such that a dimension Dp between the center of the connector portion to either main face of the plug in a height direction perpendicular to plane P is at most a track dimension Dt, said track dimension Dt being a distance in said height direction defined by the center of the slot and a carrier surface of the track.

It is thus enabled to mount track without spacing to a ceiling, shelf etc., for example via a double sided adhesive tape or Velcro provided on a carrier surface of the track, and yet rotate the plug upside-down for insertion of the plug into another end of the elongated track. It is furthermore advantageous for this purpose that the kit of parts may have the feature that the connector portion has the largest dimension of the plug in said height direction to further simplify mounting.

The kit of parts may have the feature that it further comprises at least one module, such as a lighting module, for example a lamp, a LED module, motion sensor, occupancy sensor, infrared (IR)-sensor, smoke detector, dimmer, GPS, data-communication module, which is insertable with an insertion portion in a radial direction into the elongated slot via the open side of the slot. Different types of modules might be mounted on the elongated track and be used simultaneously. Said modules find wide application and are suitable for providing lighting, lighting control like energy saving and dedicated lighting, internet services, occupancy monitoring and provide means for enhancing safety.

The kit of parts may have the feature that the open side is narrowed by two lips, each lip extending over a respective lateral groove. Thus unintentional contacting by a user of the electrical conductors provided in the elongated track is counteracted, for example in that the open side is rendered to be so small by said lips that an adult cannot insert a finger through the open side into the slot.

The kit of parts may have the feature that the plug comprises a driver which is a convention means for controlling power to the elongated track.

The kit of parts may have the feature that it comprises a further plug. Said further plug is the provided in the remaining open end and can be used to provide more power to the elongated track in case the number of mounted modules on the track is too high to be powered via a single plug. However, because the number of mountable plugs which provided power to the track is limited to maximally two, an overload of the elongated track is counteracted.

The invention further relates to a plug suitable for use in the kit of parts according to the invention, the plug having a connector portion extending along a connector axis and has two main surfaces on either side of a plane P, at least one of the main surfaces is provided with a mount feature. The plug may have the feature that it comprises at least one of a driver, a LED, an antenna, and a sensor.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG.1shows a perspective general view of first embodiment of DC, low voltage power system comprising a kit of parts1according to the invention, of whichFIG.2shows a local perspective more detailed view. The kit of parts comprises an elongated track3and at least one plug5connected via a main body8and an electric cable6of the plug to an external/remote power source (not shown). The track extends along a length axis19and comprises an elongated slot7having an open side25and is formed by a central groove9and a lateral groove11,13on either side of the central groove. Each lateral groove accommodating a respective electric current conductor15,17. The elongated track has a first end21and a second end23, the slot, the open side, the grooves, and the current conductors all extend from the first end to the second end. Via the open side a single module27is mounted on the elongated track. The module in theFIG.1is an LED module, but this can alternatively or additionally, in case more modules are mounted on the elongated track, be one or more of, for example, a lamp, an electronic dimmer, motion sensor, occupancy sensor, IR-sensor, smoke detector, dimmer, GPS, and data-communication module. The modules can be mounted in the slot on any location on the elongated track. The polarity of the parts of the power system is indicated on both the module and the plug. The plug5is to be inserted into the first end21of the elongated track and thereto comprises a connector portion29extending along a connector axis31, which in inserted portion in the slot coincides with the length axis19. The plug is also insertable with the correct polarity into the second end of the track, however, a second plug (not shown) additionally be inserted into one of the first and second end. The connector portion has a first33and a second35mutually oppositely arranged main surfaces which are bounded by side surfaces37,39each provided with a respective lateral contact41,43for electrically contacting a respective electric current conductor of the elongated track3.

FIG.2further shows a cross section of the elongated track3and of the slot7. It is clearly visible that the slot has profiled structure45rendering it to be both asymmetrical with respect to a plane P in which the central groove and the lateral grooves extend, and to be asymmetrical with respect to a plane Q which extends along the length axis perpendicular to plane P. InFIG.2the profiled structure is protruding step provided in one lateral groove. The plug5has connector cross section matching in shape with the slot cross section of the slot in that the connector portion is provided with an inversed profiled structure47to the profiled structure of the slot, i.e. a recessed portion in both main surfaces33and35. The profiled structure extends from the first end to the second end of the elongated track. The inversed profiled structure is provided in mirror configuration with respect to plane P on both main surfaces of the connector portion rendering the connector portion to be symmetrical with respect to plane P. It is further noticed that the connector cross section of the connector portion is asymmetrical with respect to plane Q. The keying function of the combination of slot cross section and connector cross section thus obtained ensures that the connector can switch between the first end and the second end with maintenance of the correct polarity. It is further shown that the central groove of the slot is provided with a further profiled structure49, in the Figure an elongated recess, which can be used for further keying function but which alternatively or additionally can be used for a firm fixation of the plug in the slot by a screw51.

Further toFIG.2it is shown that the connector portion has a thickness between the two main surfaces33and35of 2*Dp and that the dimension between the center of the connector portion to either main face here is Dp, which is less than the dimension Dt between the center77of the slot and a carrier surface75of the track in the height direction perpendicular to plane P.

FIGS.3A-Eshows a cross sectional view of parts of a second embodiment of the kit of parts according to the invention.FIG.3Ashows a slot cross section of the elongated track3in which the central groove9is provided with a protruding ridge as the profiled structure45extending along the length axis19and in an asymmetrical location with respect to plane Q over a bottom surface53of the slot7opposite the open side25of the slot. On either side of the central groove a lateral groove11,13accommodating a respective electric current conductor15,17, is provided. Respective lips71,73extend over a respective lateral groove narrowing the size of the open side and reducing the risk on unintentional touching the electrical conductors by users. The slot cross section is asymmetrical with respect to both plane P and plane Q.

FIG.3Bshows the connector cross section of the connector portion29of the plug5, matching in shape with the slot cross section shown inFIG.3A, i.e. in that the first33and second main surface35of the connector portion each is provided with an inversed profiled structure47, i.e. an indentation extending along the connector axis31. The indentations are located in mirrored position with respect to plane P. The connector cross section is asymmetrical with respect to plane Q. Each side face37,39of the connector portion is provided with a respective lateral electric contact41,43.

FIG.3Cshows the connector portion29ofFIG.3Bin inserted position in an end of the elongated track3ofFIG.3A, clearly showing the matching shape of the profiled structure45the slot cross section with the inversed profiled structure47of the connector cross section. Also shown is that each lateral contact of the connector portion contacts a respective electric current conductor embedded in a respective lateral groove of the slot.

FIGS.3D-Eshows a cross section of an insertion portion55of a module mountable on the elongated track ofFIG.3A. Thereto the insertable portion has a profile56of its cross section matching with the profile45in the cross section of the slot ofFIG.3A, i.e. it has an indented step. To ensure mounting with the correct polarity said cross section of the insertable portion comprises symmetrically arranged critical parts, for example profile56, and for non-critical parts the insertion portion55is asymmetric with respect to both plane P and plane Q, for example a mount feature58provided on both the main surfaces33,35. InFIG.3Dthe insertion portion55is provided with an indicator LED as an add-on60.FIG.3Eshows the insertion portion55with mounted add-on60of the module in mounted position on the track3ofFIG.3A.FIG.3Ealso shows that the insertion portion with its lateral electrically conducting tongues57,59contacts a respective electric current conductor15,17embedded in a respective lateral groove11,13of the slot. These tongues assist in securing the module onto the track and in preventing it from falling down, for example when the elongated track is mounted with its carrier surface to a ceiling.

FIG.3Fshows a perspective bottom view of a module27of the second embodiment of the kit of parts according to the invention. The module comprises a main part61, for example comprising a specific feature of the module, such as an LED, dimmer, sensor, GPS etc., and an insertion portion55. The insertion portion55has an elongated, rectangular shape with a short side63and a long side65. Mounting of the module onto the elongated track occurs as follows. The insertion portion is inserted via the open side of the slot into the slot with its long side parallel to the length axis of the elongated track and with its bottom face67facing towards the bottom of the slot. Subsequently the module is rotated 90° over an insertion axis69perpendicular to plane P, such that electrically conducting tongues57,59of the module establish electrical contact with the electric current conductors of the track. The profile of the cross section of the insertion portion matches with the profiled structure of the slot, and enables and ensures that the module is mounted with the correct polarity onto the track.

FIGS.4A-Cshows a cross sectional view of parts of a third embodiment of the kit of parts according to the invention. TheFIGS.4A-Care analogous to theFIGS.3A-C, yet with the profiled structure45, the inversed profiled structure47and the profile of the insertion portion essentially being reversed, i.e. the protruding ridge in the slot cross section of the track3as shown inFIG.3Ais now an elongated indentation, the indentation in the connector portion29now is a protrusion and the indented step of the profile56now is a protruding step. All further aspects are similar and fulfill the demands on asymmetry and symmetry with respect to planes P and Q as posed on both the slot of the track and the connector portion of the plug. Yet note that the slot cross section is asymmetric and the connector cross section is mirror symmetric with respect to plane P. SpecificallyFIGS.5A and5Bshow a cross sectional view of an elongated track3and inserted plug5of a fourth embodiment of the kit of parts1according to the invention. In this embodiment the elongated track has a slot7formed by a central groove9and lateral grooves11,13. The plug and track each have respective profile56,45that mutually match. Said lateral grooves are shielded by lips71extending over the lateral grooves, in said lip two pairs of electric current conductors15,17are embedded and which essentially lie symmetrically with respect to plane P. The connector portion has two pairs of electrical contacts41a,43aand41b,43b, one pair on each main surface33,35of the connector portion. The contact pairs are in mutual mirror position with respect to plane P. The main body of the plug is provided via a mount feature58provided on both the main surfaces33,35with an add-on60, in the figure a driver77.

In all the figures, the slot, the open side, the current conductors, the lips and the profiled structure extend in axial direction essentially over the whole length from the first end to the second end of the track, optionally interrupted by bridges over the open side to render the elongated track more robust.