U.S. patent number 3,601,748 [Application Number 04/827,707] was granted by the patent office on 1971-08-24 for coupling member for electrical distribution tracks.
This patent grant is currently assigned to British Lighting Industries Limited. Invention is credited to Robert Davis, Derek James Hart.
United States Patent |
3,601,748 |
Hart , et al. |
August 24, 1971 |
COUPLING MEMBER FOR ELECTRICAL DISTRIBUTION TRACKS
Abstract
A coupling member, for connecting the ends of two lengths of
electricity distribution track in which exposed track conductors
are mounted, has a pair of conductive contact members which are
resiliently mounted within a housing parallel to and insulated from
one another, the coupling member being so constructed as to be
capable of insertion into the adjacent ends of two lengths of track
with contact fingers, provided on the contact members, biased into
engagement with the track conductors.
Inventors: |
Hart; Derek James (N/A, EN),
Davis; Robert (N/A, EN) |
Assignee: |
Limited; British Lighting
Industries (EN)
|
Family
ID: |
10371852 |
Appl.
No.: |
04/827,707 |
Filed: |
May 26, 1969 |
Foreign Application Priority Data
|
|
|
|
|
Jul 22, 1968 [GB] |
|
|
34941/68 |
|
Current U.S.
Class: |
439/115 |
Current CPC
Class: |
H01R
25/14 (20130101); H02G 5/04 (20130101) |
Current International
Class: |
H02G
5/00 (20060101); H01R 25/00 (20060101); H02G
5/04 (20060101); H01R 25/14 (20060101); H01R
003/06 () |
Field of
Search: |
;339/14,21,22,23
;174/99B |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Purser; Ernest R.
Assistant Examiner: Hafer; Robert A.
Claims
We claim:
1. A coupling member for connecting the ends of separate lengths of
electricity distribution tracks which carry exposed
track-conductors, the coupling member comprising:
a housing,
a pair of conductive contact members mounted parallel to and
insulated from one another in said housing,
track-locating projections on the external surfaces of said
housing,
said locating projections positioning the coupling member, when
connected between two lengths of track, with its conductive contact
members abutting the said track-conductors, and
further projections located to abut the ends of the track
conductors when the coupling member is in position for connecting
two lengths of track, whereby relative movement between the
coupling member and the two lengths of track is transmitted to the
track conductors to move them longitudinally away from the adjacent
ends of the two lengths of track.
Description
The present invention relates to a coupling member for electrical
distribution tracks.
The coupling member is designed to join together the ends of
electric distribution tracks in such a way that electrical
continuity is established from track to track, without the
necessity of making conventional mechanical or soldered electrical
connections. The coupling member is especially suitable for joining
electrical distribution tracks which carry bare conductor elements,
and is particularly, but not exclusively, suitable for use with the
track described in our pending application of even date entitled
"Track for Distribution of Electricity."
According to the present invention, there is provided a coupling
member for connecting the ends of separate lengths of electric
distribution tracks, comprising a housing in which a pair of
conductive contact members is mounted parallel to and insulated
from one another, the contact members being so spaced as to be able
to engage conductors carried in the tracks, the housing having
projections therefrom for engaging with the tracks to locate the
coupling member with the contact members abutting the conductors
when the coupling member is positioned to connect the tracks.
The coupling member is partially inserted into the end of one
length of track, so that part of the member projects from the end
of the track. The other end of the coupling member is then inserted
into a second length of track. Preferably, the housing is
asymmetrical in cross section. The tracks, being also of
asymmetrical cross section, can only be connected with the coupling
member in one way. Thus reversal of the tracks end-for-end will
prevent their connection with the coupling member. In this way, the
power supplied by each length of track to appliances through
special output adaptors always has the correct polarity. The
contact members are so arranged that they abut the conductors
carried by the tracks when the coupling member is in position
joining two lengths of track. In addition, the coupling member
preferably includes a further contact member, which abuts a third
conductor carried by each of the tracks when the coupling member is
in position. Continuity between the third conductors, which may
form an earth line, is thus established. It will be appreciated
that electrical continuity is automatically achieved by mechanical
contact of the conductors with the contact members. It is therefore
unnecessary to make conventional connections by soldering or by
wiring into known devices such as screw-clamping connectors.
The present invention will now be described by way of example with
reference to the accompanying drawing which is an exploded
perspective view of a coupling member and electric distribution
tracks.
As shown in the drawing, the track 10 consists of an elongate
member made from an extrusion of a plastics material such as P.V.C.
The track has a base 11, and sides 12, 13 extending perpendicularly
from the longitudinal edges thereof. The sides 12, 13 include
housings for conductor strips 15, 16 which are connected to an
electrical supply. The strips are accessible from the inner region
of the track 10 by way of slots 19, 20. A third conducting strip 21
is carried by the base 11 of the track 10, and provides an earth
line. The sides 12, 13 of the track 10 additionally include flanges
22, 23 which project inwardly from the sides 12, 13 of the track.
The flanges extend lengthwise of the track and provide rails on
which a coupling member can be positioned.
The coupling member 30 includes a housing 31 in which a pair of
contact members 32, 33 is mounted. The housing 31 can be moulded
from a rigid plastics material such as P.V.C. Inner walls 34, 35
are located parallel to and spaced apart from one another inside
the housing 31. The contact members 32, 33 are secured to the walls
34, 35 on resilient mountings. In the embodiment shown, the
resilient mountings comprise plugs or rivets 36 and helical coil
springs 37. The contact members 32, 33 are assembled in the housing
31 by passing the plugs 36 through apertures 38 and 39 provided in
the housing 31 and the contact members respectively. The apertures
38, 39 are so dimensioned that the plugs 36 are a force fit
therein. The helical springs 37 are positioned on the plugs 36
between the inner surfaces of the contact members 32, 33 and the
walls 34, 35. It will be appreciated, therefore, that the helical
springs 36 bias the contact members 32, 33 away from each other in
a lateral direction.
The contact members 32, 33 include portions which are bent out from
the members, to form contact fingers 40 which can engage the
conductor strips 15, 16 carried by the track 10. It will be
appreciated that the contact fingers 40 project outwardly from the
sides of the housing 31. Each contact member has two such contact
fingers, which are separated from one another by a slot 41. The
contact members can be made from a material such as copper.
The housing 31 additionally carries a further contact strip 42,
which is positioned between the walls 34, 35. The contact strip 42
is secured to a spacer 43, attached to the walls 34, 35, by means
of a conventional "pop" rivet 44 which is passed through apertures
45 and 46 in the contact strip 42 and the spacer 43. The contact
strip 42 is provided to establish continuity between the earth line
conductors 21 carried by the tracks 10. The strip 42 can be made
from a spring steel.
It will be seen from the drawing that, in cross section, the tracks
10 are asymmetrical about a central plane parallel to the sides 12,
13. In particular, adjacent side 12 there is a groove 47 and
adjacent the side 13 the base includes a surface 48 which is
inclined towards the conductor strip carried by the side 13. The
housing 31 of the coupling member is so shaped that it can only be
inserted into the end of the track 10 in one way. Thus, the housing
31 includes, when viewed in plan a square corner =A, which will
project into the groove 47 of the track when the coupling member is
positioned in the end of the track. The opposite corner B of the
housing 31 is inclined corresponding to the inclined surface 48 of
the base 11. If the coupling member 30 were reversed end-for-end,
the square corner A would abut the track in the zone of the
inclined surface 48, and prevent the insertion of the coupling
member 30. When the coupling member has been correctly inserted in
the end of one length of track, a second length of track can be
connected to the coupling member. It will be appreciated that only
one end of the second track will fit over the coupling member,
owing to their a symmetry. When connected to a supply line, the
polarity of, for example the track conductor 16, adjacent the
groove 47 in the base 11, will be identical from track to track.
The power supplied to appliances through similarly asymmetrical
track output connectors will therefore be of the correct polarity.
The housing 31 is additionally provided with projections 49 which
rest on the flanges 22, 23. The projections 49 are so positioned
relative to the contact fingers 40 that when the coupling member is
positioned on the track, the contact fingers 40 can engage the
track conductors. In addition, the housing 31 includes further
projections in the form of lugs 50. The lugs 50 are so positioned
that, on inserting the coupling member 30 into the track 10, the
lugs can abut the ends of the track conductors 15, 16. Movement of
the coupling member 30 into the track will then move the track
conductors 14, 15 away from the end of the track. This ensures that
the track conductors cannot be accidentally touched, and
furthermore avoids electrical tracking between the conductors and a
mating metal cover track.
As will be seen from the drawing, the earthing strip 42 is provided
with apertures 52. The apertures 52 include raised circumferential
lips. When the coupling member 30 is inserted into the track 10,
the raised lips of the apertures 52 contact the third conducting
strip 21 of the track 10, bending the earthing strip 42 downwards
as viewed in the drawings. A countersunk portion is formed in the
strip 21, to accept the raised lips of the corresponding aperture,
when the coupling member 30 is inserted to the requisite distance
into the track 10.
To connect two lengths of track 10, the coupling member 30 is
inserted into the end of one track. As explained, the coupling
member 30 can be inserted into the ends of lengths of track in one
way only. The housing 31 is so positioned relative to the track 10
that the underside of the projections 49 coincide with the top
surface of the flanges 22, 23 of the track. The contact members 32,
33 are moved towards each other, and the coupling member is
inserted into the end of the track. The contact members 32, 33 are
then released. The projections 49 are so located that when the
contact members are released, the contact fingers 40 pass through
the passages 19, 20 to abut the conductor strips 15, 16. Efficient
electrical contact between the fingers 40 and the conductor strips
15, 16 is maintained by means of the biasing of the contact members
32, 33 provided by the springs 37. When the coupling member has
been fully inserted in the tracks, the contact fingers 40 of the
contact members 32, 33 are completely housed within the track 10.
Thus the contact members cannot be touched accidentally. The other
length of track is then connected to the coupling member in a
similar manner.
Once the coupling member is positioned between two lengths of
track, it can be locked in place by means of fixing screws 51 which
extend through the apertures 52 provided in the spring steel
earthing strip 42. The coupling member thus provides simple
electrical connection between separate lengths of electrical
distribution track. When positioned, the coupling member
automatically connects the conductors carried in the track thereby
eliminating conventionally formed connections. The correct polarity
is ensured from track to track since the coupling member can be
positioned in the tracks in one way only.
* * * * *