[0001] This invention relates to lighting track systems, and in particular to systems of
the kind in which lights or other electrical devices are electrically connected to
a track incorporating power supply means, by means of a mounting device which also
retains the device in position, on the track. The invention relates particularly (although
not exclusively) to lighting systems of the low voltage type.
[0002] According to the present invention, there is provided a lighting track system comprising
a mounting device adapted for cooperation with a track incorporating electrical contact
means, the mounting device comprising a carriage including contact means adapted to
cooperate with the electrical contact means of the track, and retaining means,adapted
to hold the carriage in a desired position on the track, and comprising displaceable
locking means which can be moved between a first position in which the carriage can
be engaged with the track, and a second position in which the locking means locks
the carriage to the track. Preferably, the track has a longitudinally extending recess
which incorporates the electrical contact means, and said locking means is adapted
to be moved between a retracted position (the first position) in which the carriage
can be inserted into or released from the track, and a protruding position (the second
position) in which they engage with corresponding opposed internal faces of the recess.
[0003] Preferably, the locking means comprises at least one set of oppositely facing abutment
members formed from a relatively resilient material, so as to be inherently biassed
either towards the engaged position or the released position; and at least one set
of cooperating camming means, whereby relative movement of the locking means and the
camming means results in displacement of the locking means between the locked and
released position.
[0004] In a preferred embodiment of the invention, there are two sets of camming means for
each set of abutment members, the abutment means being movable between the released
position, in which they are held by one set of camming means, and the engaged position
in which they are held by the other set of camming means.
[0005] Preferably, each set of abutment members comprises at least one pair of mutually
opposed wings or claws which are resiliently biassed towards one of the said positions,
and the camming means comprises a tapered member which is slidably engageable with
the said members, so as to urge them towards the other of the said positions.
[0006] In a preferred embodiment of the invention, the abutment members comprise at least
one pair of mutually opposed wings or claws whcih are resiliently biassed apart, towards
an outward locked position, and two sets of camming means one set comprising a tapered
slot, the wings or claws being mounted on a sub-assembly of the carriage and being
slidable in the said tapered slot; so as to be urged together by the taper of the
slot at one extreme position, whilst the other set of camming means comprises a tapered
member which projects between the wings at the other extreme position so as to hold
them apart.
[0007] Some embodiments of the invention will now be described by way of example with reference
to the accompanying drawings, in which:
Figure 1 is an exploded view of the operative parts of a lighting track system in
accordance with the invention;
Figure 1a is an enlarged view of part of Figure 1, to illustrate the electrical connections
in more detail;
Figure 2a is an elevational view of a contact member for the electrical connections;
Figure 2b is a side elevation of the contact member of Figure 2a;
Figure 3a is a plan view of the locking means of the carriage in its engaged or locked
position;
Figure 3b is a plan view of the carriage in the released position; and
Figure 4 is an exploded view of an alternative form of lighting track system in accordance
with the invention.
[0008] Referring to Figure 1, a track 2 of generally conventional form comprises an elongate
body which may for example be an aluminium extrusion, having a generally circular
external profile, and a longitudinally extending recess 4. The opposite internal faces
of the recess 4 carry conductor wires 6 and 8 whcih are mounted in respective electrically
insulating housing strips 10 and 12, which are retained in correspondingly shaped
re-entrant slots in either side of the recess.
[0009] A carriage 14 is adapted to be releasably located in the track, as explained in more
detail below, and carries a contact assembly 16, adapted to make connections with
the conductors 6 and 8 of the track, and a downwardly dependent mounting barrel (18)
having a threaded lower end which carries a light fitting (not shown).
[0010] As shown more clearly in Figure 1a, the electrical connections between the fitting
and the track are made via a pair of wires 20 whose upper ends are suitably connected
to respective downwardly extending contact members 22 of the contact assembly 16.
The upper ends of the contact members comprise enlarged plate-like portions 24 whose
upper and lower edges are inwardly flanged at 26.
[0011] This is illustrated in more detail in Figures 2a and 2b from which it will be seen
that the downwardly extending portions of the contact members are shaped to fit the
sides of the support member and are also provided with fixing holes 25 at their lower
ends to facilitate the attachment of a connector.
[0012] A support member 28 for the contact assembly comprises a generally T-shaped body,
having a downwardly dependent stem 30, each side of which is formed with a channel
which receives the downwardly extending end of the corresponding contact member 22.
[0013] The head 32 of the contact support member 28 is somewhat enlarged in cross-section,
and is formed with a slot 34 on each side which receives and locates the flange 26
of the corresponding contact member.
[0014] The top of the head 32 also carries endwise projecting tapered portions 33 described
in more detail below, and has downwardly dependent lug positions 35 at each end which
lock the contact member into a slot 37 in the centre of the carriage. Thus in the
assembled condition of the contact assembly 16 and carriage 14 the contact members
and the support member 28 are securely held in location with one another. As seen
in Figure 1a, this assembled condition brings the contact plate members 24 into approximate
alignment with the corresponding side faces of the carriage 36 which in use, extend
into the recess 4 of the track 2, so that the contact members 24 are brought into
contact with the conductors 6 and 8 in the track. Since the contacts 24 are stamped
from a suitably resilient metal, and somewhat convex in cross-section so that they
protrude outwardly from the head 32 of the contact support member 28, they are urged
into intimate contact with the conductors of the track.
[0015] Referring to Figure 1 and Figures 3a and 3b the opposite ends of the carriage 14
are formed with an elongate tapered slot 38, in which is mounted a locking sub-assembly
40. The sub-assembly 40 comprises a main body forming a slider, whose upper surface
is formed with a longitudinally extending recess 42 which is shaped to cooperate with
the underside of the end portion 44 of the carriage, which, as can be seen from the
drawing, is of generally "top hat" shaped cross-section. The upper surface of the
slider carries a pair of upwardly extending, wing like locking members 46, 48, having
oppositely facing flanged projections 50, 52 at their upper ends. The wing members
are staggered longitudinally of the slider, so that the "leading edge" of one projection
50 is approximately level with the "trailing edge" 56 of the other projection 52.
[0016] Since the "wings" and the body 40 are moulded from resilient plastics material, the
slider can be assembled onto the carriage 14 as illustrated at the righthand side
of Figure 1, by squeesing the wings together and inserting them through the base of
the tapered slot 38, at the inner end of the slot which is wider. The natural resilience
of the material then causes the wings to move outwardly so that the flanged portions
52 and 54 hold the slider in position on the carriage, again as illustrated on the
righthand side of Figure 1.
[0017] As can be more clearly seen from Figures 3a and 3b the slot 38 has a relatively wide
inner section and a relatively narrower outer end portions, there being a short tapered
region 58, 60 on each side of the slot adjacent each end. The positions of the tapered
regions 58 and 60 are staggered in the same relationship as the locking wings 46 and
48 of the slider, and thus it will be seen that when the slider is in its installed
position, the action of moving the slider 40 in an axially outward direction urges
the two wings 46 and 48 laterally inwards, so that the assembled carriage can then
be offered up for insertion to the track. When the sliders 40 are subsequently moved
to their axially innermost postion, therefore, the wings 46 and 48 will be allowed
to move laterally outwards, so as to engage against the opposed internal side walls
of the track. As can be seen from the Figure, the arrangement of the conductors 6
and 8 and their corresponding mounting strips 10 and 12 is such that recesses are
formed above them to receive the outer extremities of the wings 46 and 48 of the slider.
[0018] In order to securely lock the wings in this position, they also engage around the
tapered end projections 33 of the head 32, in the inner position, Figure 3a, and again
as will be seen more clearly from Figure 3b, the projections 33 are so shaped on each
side that they match the offset of the wings.
[0019] Figure 4 shows an alternative form of the invention, which again includes a track
2 having internal contact members 6 and 8, a mounting member 18 for a light fitting,
a carriage 14, and a pair of opposed contact members 24 on a contact support member
28. The general relationship of the parts is similar to that of Figure 1, but the
arrangement for locking the carriage into the track is slightly different, as will
be explained in more detail below.
[0020] In the case of the Figure 4 embodiment, each outer end 80 of the carriage 40 is bifurcated,
to form a pair of parallel arms 82, and a slider 84 is formed with a vertically upstanding
central flange 86 which fits between the arms 82.
[0021] A pair of locking wings 88 are integrally formed with the carriage 14, and have laterally
outwardly extending flanges on their upper ends. A tapered formation 90, carried on
the upper end of the flange 86 of the slider, is urged between the wings 88 as the
slider is moved towards its axially innermost position, as shown at the righthand
side of Figure 4. It will thus be appreciated that the carriage can be inserted onto
the track, with its sliders in axially outward positions, and the sliders subsequently
moved inwards to lock the wings into position against the opposed internal side walls
of the track 2.
[0022] Modifications of the invention may be made without departing from the scope thereof.
For example, the carriage and locking arrangement may be modified so that the locking
means engages with and locks to the outside of the track in addition to or instead
of the inside of the track.
1. A lighting track system comprising a mounting device for cooperation with a track
incorporating electrical contact means, the mounting device comprising a carriage
(14) including contact means (24,22) adapted to cooperate with the electrical contact
means (6,8) of the track (2), and retaining means, comprising at least one pair of
mutually opposed abutment members (46, 48) adapted to hold the carriage in a desired
position on the track (2), and comprising displaceable locking means comprising camming
means including a tapered member (33) which is slidably engageable with said retaining
means so as to move same between a first position in which the carriage (14) can be
engaged with the track (2) and a second position in which the locking means locks
the carriage to the track (2).
2. A lighting track system according to Claim 1, wherein there are two sets of cammings
means (33, 38) for each set of abutment members (46,48), the abutment means being
movable between the released position, in which they are held by one set of camming
means (38), and the engaged position in which they are held by the other set of camming
means (33).
3. A lighting track system according to Claim 2, wherein the abutment members (46, 48)
comprise at least one pair of mutually opposed wings or claws which are resiliently
biassed apart, towards an outward locked position, and two sets of camming means (33,
38) one set comprising a tapered slot (38), the wings or claws being mounted on a
sub-assembly (40) of the carriage (14) and being slidable in the said tapered slot
(38); so as to be urged together by the taper of the slot at one extreme position,
whilst the other set of camming means (33) comprises a tapered member which projects
between the wings at the other extreme position so as to hold them apart.
4. A lighting track system according to Claim 1, wherein each set of abutment members
(46, 48) comprises resiliently deflectable members which are engageable by the camming
means upon the camming means being slidably moved relative to the abutment members
to spread the abutment members from the protracted position in which the abutment
members are unstressed to the protruding position in which the abutment members are
resiliently spread apart.
5. A lighting track system comprising a mounting device adapted for cooperation with
a track incorporating electrical contact means, the mounting device comprising a carriage
including contact means adapted to cooperate with the electrical contact means of
the track, and retaining means, adapted to hold the carriage in a desired position
on the track, and comprising displaceable locking means which can be moved between
a first position in which the carriage can be engaged with the track, and a second
position in which the locking means locks the carriage to the track.
6. A lighting track system according to Claim 1, wherein the track has a longitudinally
extending recess which incorporates the electrical contact means, and said locking
means is adapted to be moved between a retracted position (the first position) in
which the carriage can be inserted into or released from the track, and a protruding
position (the second position) in which they engage with corresponding opposed internal
faces of the recess.
Amended claims in accordance with Rule 86(2) EPC.
1. A lighting track system comprising a mounting device adapted for cooperation with
a track incorporating electrical contact means, the mounting device comprising a carriage
(14) including contact means (22,24) adapted to cooperate with the electrical contact
means (6,8) of the track (2), and retaining means (46,48), adapted to hold the carriage
in a desired position on the track (2), and comprising displaceable locking means
which can be moved between a first position in which the carriage can be engaged with
the track, and a second position in which the locking means locks the carriage to
the track characterised in that said locking means includes two sets of camming means
(33,38) for said retaining means (46,48), the retaining means being moveable between
the release position, in which they are held by one set of camming means (38), and
the engaged position in which they are held by the other set of camming means (33).
2. A lighting track system according to Claim 1, wherein said retaining means comprises
at least one pair of mutually opposed abutment members.
3. A lighting track system according to Claim 2, wherein the abutment members (46, 48)
comprise at least one pair of mutually opposed wings or claws which are resiliently
biassed apart, towards an outward locked position, and two sets of camming means (33,
38) one set comprising a tapered slot (38), the wings or claws being mounted on a
sub-assembly (40) of the carriage (14) and being slidable in the said tapered slot
(38); so as to be urged together by the taper of the slot at one extreme position,
whilst the other set of camming means (33) comprises a tapered member which projects
between the wings at the other extreme position so as to hold them apart.
4. A lighting track system according to Claim 2 or 3, wherein each set of abutment members
(46, 48) comprises resiliently deflectable members which are engageable by the camming
means upon the camming means being slidably moved relative to the abutment members
to spread the abutment members from the protracted position in which the abutment
members are unstressed to the protruding position in which the abutment members are
resiliently spread apart.
5. A lighting track system according to Claim 1, wherein the track has a longitudinally
extending recess which incorporates the electrical contact means, and said locking
means is adapted to be moved between a retracted position (the first position) in
which the carriage can be inserted into or released from the track, and a protruding
position (the second position) in which they engage with corresponding opposed internal
faces of the recess.