[0001] This invention relates to electrical connectors of the kind comprising first and
second matable body parts, each carrying electrical terminals, the electrical terminals
of the first body part engaging those of the second body part when the first and second
body parts are in mating engagement.
[0002] In a known form of connector of the kind specified above the body parts are moulded
in a synthetic resin material and the first body part has an integral, thin walled
shroud at one axial end within which an appropriate axial end region of the second
body part is received when the first and second body parts are interengaged in use.
In order to avoid unintentional disengagement of the first and second body parts a
latching arrangement is provided comprising a pair of latch members integral with
opposite walls respectively of the second body part and which, when the body parts
are interengaged, extend externally of the shroud and coact with respective projections
extending integrally from the outer surface of opposite sides of the shroud. The projections
are received within respective apertures in the latch members. The latch members are
of strip-like form and lie generally parallel to and spaced from the opposite walls
of the second body part, being joined thereto by flexible integral neck regions extending
at right angles to the latch members. The projections of the first body part are of
ramp-like form whereby during interengagement of the first and second body parts the
latch members are deflected outwardly by the projections, and as permitted by flexing
the respective neck regions. When the first and second body parts are fully interengaged
the projections align with the apertures in the latch members and the latch members
restore to their original positions so that the projections are received within the
apertures and disengagement of the first and second body parts is resisted. Intentional
disengagement can be achieved by outward movement of the latch members to clear the
projections thus permitting the body parts to be pulled apart. Such movement of the
latch members can be achieved by applying pressure to the opposite ends of the latch
members from the projections, the neck regions being disposed between the ends of
the latch members so that the latch members perform a rocking action.
[0003] It will be recognised that in order for the latching arrangement to operate satisfactorily
a certain degree of accuracy in the positioning of the projections in relation to
the latch members is called for. Moreover, in order to ensure that mating terminals
of the two body parts can interengage then there must be sufficient clearance between
the interior of the shroud and the end region of the second body part to permit slight
misalignment of the terminals to be accommodated. It -has been found that owing to
the thin walled nature of the shroud inward bowing of the walls can occur as the material
of the shroud cools at the end of the moulding process. Such bowing can result in
the projections not being sufficient accurately located in relation to the latch members
to achieve a reliable latching action. In order to overcome this problem, that is
to say in order to avoid the bowing, and thus the mis-positioning of the projections,
it has previously been proposed to permit the first body part to cool, at the end
of the moulding process, either in the mould itself, or on a former which supports
the shroud during cooling. While this previous proposal overcomes the problem by preventing
the inward bowing of the shroud walls it greatly increases the production time of
the first body part, and therefore greatly increases the cost of production of the
first body part. It is an object of the present invention to provide an electrical
connector wherein reliable latching can be achieved, and wherein the disadvantages
of the previous proposal are minimised.
[0004] An electrical connector in accordance with the present invention comprises a first
moulded synthetic resin body part for receiving first electrical terminals, said first
body part including at one end thereof an integral thin-walled shroud, a second moulded
synthetic resin body part for receiving second electrical terminals interengageable
in use with said first electrical terminals, said second body part having an end region
which, when the first and second body parts are interengaged, is received within said
shroud of said first body part, first and second latch members on said second body
part, said first and second latch members extending externally of said shroud when
said first and second body parts are interengaged, first and second external projections
on said shroud, said first and second external projections being engageable in use
with said first and second latch members respectively, and, localized ramp means on
said end region of said second body part, said ramp means, when said first and second
body parts are interengaged, coacting with the inner surface of said shroud, to ensure
that at least those portions of the shroud carrying said first and second projections
are so positioned in relation to the second body part that said first and second projections
can coact with said first and second latch members to afford a latching action.
[0005] Preferably said ramp means comprises a pair of upstanding ribs on opposite sides
respectively of said end region of said second body part said ribs extending axially
of the second body part and tapering in height from a minimum at their ends adjacent
the front end of the second body part.
[0006] Desirably said ribs include a plateau region at their maximum height ends.
[0007] Preferably said ribs commence, at their minimum height end, at a point spaced rearwardly
from the front end of the second body part.
[0008] Conveniently there is a pair of laterally spaced parallel ribs on one side of said
end region of said second body part and a single centrally disposed rib on the opposite
side of said end region.
[0009] One example of the present invention is illustrated in the accompanying drawings,
wherein:
Figure 1 is a side elevational view partly in section of the first and second body
parts of an electrical connector, showing the body parts interengaged;
Figure 2 is a sectional view of the first body part shown in Figure 1;
Figure 3 is a side elevational view of the second body part shown in Figure 1; and
Figures 4 and 5 are views in the directions of arrows A and B in Figures 2 and 3 respectively.
[0010] Referring to the drawings, the electrical connector includes first and second moulded
synthetic resin body parts 11, 12. The body part 11 is formed with a plurality of
axially extending passages 13 and extending from one end of the body 11 is an integral,
thin-walled shroud 14. The body 11 includes an end face 15 at the base of the shroud,
the passages 13 opening at one end at the face 15, and opening at their opposite ends
at the opposite axial end 16 of the body 11. In use the passages 13 each receive a
respective electrical terminal which is located and retained by engagement with its
passage wall in known manner. Each of the terminals is a pin terminal, and is electrically
connected to one or more respective electrical leads. The leads extend in use from
the body 11 at the end face 16, and the pin portions of the pin terminals project
from the face 15 parallel to one another within the shroud 14.
[0011] As is evident from Figure 4 the passages 13 are arranged in two parallel rows, and
the passages in the two rows are staggered, one of the rows having one more passage
than the other row. In cross-section therefore the body 11 and the shroud 14 are trapezoidal
having a pair of parallel sides and a pair of sides inclined towards one another.
[0012] Adjacent the free edge of the shroud 14, and centrally disposed across the parallel
sides thereof are first and second integral, outwardly extending projections 17, 18.
The projections 17, 18 are of barb-like form tapering from a minimum height at the
free edge of the shroud 14 to a maximum height at their opposite axial end, where
they terminate in a shoulder (indicated by the suffix a in Figure 2) which subtends,
with the outer surface of the shroud 14, an acute angle approaching 90°.
[0013] The body part 12 is also moulded in synthetic resin material, and includes an end
region 19 engageabl.e within the shroud 14 of the body part 11. As is clear from Figures
1 and 5 the body part 12 has a plurality of axially extending passages 21 which are
disposed in the same arrangement as the passages 13 of the body part 11. The passages
21 extend through the body part 12 from the front end, that is to say the free end
of the region 19, to the rear end 22 and in use receive respective socket terminals
each of which is electrically connected to one or more respective electrical leads.
The leads leave the passages 21 at the end 22 of the body and the socket regions of
the terminals are received within the end region 19 of the body 12. When the body
part 11, 12 are interengaged as shown in Figure 1, the pin regions of the terminals
of the body 11 enter the end region 19 of the body 12 and engage within the socket
regions of the terminals of the body part 12.
[0014] It can be seen that the region 19 of the body 12 is in fact defined by a plurality
of parallel sleeves 23 extending axially of the remainder of the body 12 for receiving
respective socket terminals. The sleeves 23 are of generally circular cross-section
and are arranged in two rows with the sleeves being staggered and one row having one
more sleeve than the other row. The two rows are separate, but within each row the
sleeves merge into one another as is best seen in Figure 5.
[0015] In an end view it will be recognised that the body part 12 has a trapezoidal form
similar to that of the body part 11, and projecting outwardly from the two parallel
sides of the body part 12 are first and second flexible neck regions 24, 25. Integral
with the end of each neck region 24, 25 remote from the body part 12 is a respective
latch member 26, 27. The latch members 26, 27 extend parallel to the remainder of
the body part 12 and are spaced therefrom by the neck regions 24, 25. The neck regions
24, 25 join with their respective latch members 26, 27 intermediate the ends of the
latch member and thus by pressing one end of its latch member towards the body part
12, that latch member can be rocked relative to the body part 12 as permitted by flexure
of its respective neck region. Upon release the neck region will restore the latch
member to its position generally parallel to the body part 12.
[0016] At their forward ends, that is to say their ends adjacent the end region 19, the
latch members 26, 27 are formed with apertures (indicated by the suffix a in Figure
3). As is clear from Figure 1, when the body parts 11, 12 are interengaged the projections
17, 18 of the body part 11 can be received within the apertures 26a, 27a so that the
closed ends of the apertures 26a, 27a coact with the shoulders 17a, 18a, to resist
disengagement of the body parts 11, 12. In order to permit disengagement the rearward
ends of the latch members 26, 27 are pressed towards the body part 12 thus rocking
the latch members to lift their forward ends out of engagement with the projections
17, 18 and permit movement of the body parts 11, 12 away from one another. The inclined
surfaces of the projections 17, 18 facilitate interengagement of the body parts without
the need manually to rock the latch members 26, 27 since the free forward ends of
the latch members ride up the inclined surfaces of the projections 17, 18 as the body
parts are pushed into engagement with one another. The latch members 26, 27 spring
back to their parallel configurations to embrace the projections 17, 18 when the body
parts are fully interengaged.
[0017] The opposite faces of the end region 19 of the body part 12 are provided with localized
ramp means 28, 29 which, when the body parts are interengaged, can, if necessary,
engage the inner surface of the shroud 14 to push those regions of the shroud 14 carrying
the projections 17, 18 outwardly. The ramp means 28 comprises a pair of parallel ribs
integral with and projecting from the outer surface of the two centrally disposed
sleeves of the upper row of sleeves 23. The ribs commence a short distance back from
the front end of the portion 19 and taper in height from zero, in a rearward direction,
to a maximum which is then maintained throughout a plateau region. The ramp means
29 is a similarly shaped rib on the central sleeve of the lower row of sleeves.
[0018] It will be recognised that the front end of the region 19 of the body part 12 is
of _smaller dimensions than the intended interior dimension of the shroud 14, thus
permitting the front end of the region 19 readily to be inserted into the shroud.
In other words there is an adequate clearance between the front end of the end region
19 of the body part 12 and the inner wall of the shroud to facilitate easy insertion
even if the parallel walls of the shroud are in fact bowed inwardly as may well be
the case as a result of unsupported cooling of the shroud at the end of the moulding
process. However, in the event that the walls of the shroud do bow inwardly, co-operation
of the projections 17, 18 with the latch members 26, 27 is assured by the provision
of the ramp means 28, 29, since after the front end of the region 19 has been introduced
into the shroud the inner wall of the shroud will be engaged by the inclined portions
of the ribs constituting the ramp means 28, 29 and the walls of the shroud will thus
be flexed outwardly by coaction with the inclined regions of the ribs. The walls of
the shroud will be held in their outwardly displaced positions by the plateau regions
of the ribs and thus engagement of the projections 17, 18 with the latch members 26,
27 is ensured.
[0019] It will be recognised therefore that the body part 11 can be manufactured without
the need for increased production time and therefore increased cost of allowing the
body part 11 to cool in the mould, or with the shroud 14 engaged on a former.
[0020] It is to be understood that other body part shapes and terminal configurations, to
those described above and shown in the drawings, can be used if desired.
1. An electrical connector comprising a first moulded synthetic resin body part (11)
for receiving first electrical terminals, said first body part including at one end
thereof an integral thin-walled shroud (14), a second moulded synthetic resin body
part (12) for receiving second electrical terminals interengageable in use with said
first electrical terminal, said second body part having an end region (19) which,
when the first and second body parts (11, 12) are interengaged, is received within
said shroud (14) of said first body part (11), first and second latch members (26,
27) on said second body part (12), said first and second latch members (26, 27) extending
externally of said shroud (14) when said first and second body parts (11, 12) are
interengaged, and first and second external projections (17, 18) on said shroud (14),
said first and second external projections (17, 18) being engageable in use with said
first and second latch members (26, 27) respectively, characterized in that localized
ramp means (28, 29) is provided on said end region (19) of said second body part (12),
said ramp means (28, 29), when said first and second body parts (11, 12) are interengaged,
coacting with the inner surface of said shroud (14), to ensure that at least those
portions of the shroud (14) carrying said first and second projections (17, 18) are
so positioned in relation to the second body part (12) that said first and second
projections (17, 18) can coact with said first and second latch members (26, 27) to
afford a latching action.
2. An electrical connection as claimed in Claim 1 characterized in that said ramp
means (28, 29) comprises a pair of upstanding ribs on opposite sides respectively
of said end region (19) of said second body part (12), said ribs extending axially
of the second body part (11) and tapering in height from a minimum at their ends adjacent
the front end of the second body part (12).
3. An electrical connector as claimed in Clairm characterized in that said ribs include
a plateau region at their maximum height ends.
4. An electrical connector as claimed in Claim 2 or Claim 2 characterized in that
said ribs commence, at their minimum height end, at a point spaced rearwardly from
the front end of the second body part (12).
5. An electrical connector as claimed in any one of Claims 2 to 4 characterized in
that there is a pair of laterally spaced parallel ribs (28) on one side of said end
region (19) and a centrally disposed rib (29) on the opposite side of said region
(19).