Connector built from one or more single rowed housings with long lasting locking mechanism

A connector is disclosed for connecting a main housing with a fixed base. The housing has an engagement aperture formed on its side, and includes a lock mechanism having a catch piece formed with a bent intermediate portion, a protruding pressable portion, a protruding engaging portion formed with a catch shape for engaging with a fixed base, and an elastic tongue removable engaged into the aperture so as elastically to support the catch piece on the side of the housing with its bent portion pressing thereagainst and acting as a fulcrum, with the tongue biasing the protruding pressable portion in the direction away from the housing and the protruding engaging portion in the direction towards the housing.

BACKGROUND OF THE INVENTION 
The present invention relates to the field of electrical connectors, and 
more specifically relates to a novel type of electrical connector which 
can be built up from one or several single layered slabs, and which has a 
novel type of long lasting locking mechanism for locking it to a base 
portion. Such an electrical connector may be used, for example, for 
connecting electrical conductors for transmission of electrical signals 
between a computer and a terminal, or the like. 
A conventional type of electrical connector is for example of the type 
exemplarily shown in perspective view in FIG. 4 of the accompanying 
drawings; this exemplary connector is a two row type connector. In this 
drawing, the housing for the connector is designated by the reference 
numeral 1, and this housing 1 has a mating end 1a on its one side and a 
terminal fitting end 1b on its other end. The portion of the housing 1 at 
the connector fitting end 1b is formed as a terminal insertion portion 3 
formed with a plurality of sheathed electric wire connection holes 4 
opening to the terminal fitting end 1b at fitting openings 6, said 
terminal insertion portion 3 being open at the top side thereof as seen in 
the figure, and each of these sheathed electric wire connection holes 4 
extends through the housing 1 of the connector to open at its mating end 
1a as an insertion hole 5 for a male terminal formed on an external base, 
not particularly shown. This electrical connector is used, in a manner not 
particularly shown in the drawings, by fitting a female terminal into each 
of the plurality of sheathed electric wire connection holes 4, through the 
fitting openings 6 from the terminal fitting end 1b side of the housing 1, 
so that the respective ends of said female terminals oppose the respective 
insertion holes 5. Then the ends of sheathed electrical wires (also not 
particularly shown) are passed through the fitting openings 1 and are 
joined to the other ends of said female terminals by crimping or soldering 
or the like process, and finally a cover (also not shown) is fitted over 
the open side of the terminal insertion portion 3, so as to securely hold 
the female terminals in the housing 1. And, in use, the mating end 1a of 
the connector is approached towards a base (not particularly shown) which 
has a plurality of male terminals protruding therefrom in an identical 
configuration to at least some of the insertion holes 5, with the 
electrical wires connected to the other ends of the female terminals 
trailing out from the terminal fitting end 1b of the connector, and said 
male terminals are thus inserted into their said insertion holes 5 so as 
to mate with the respective female terminals therein and make electrical 
contact therewith. 
Further, as shown in schematic end on view in FIG. 8 of the accompanying 
drawings, in some cases a locking mechanism for such a connector is 
conventionally provided, for locking the main body of the connector, 
designated in this figure by the reference numeral 103, to a base 101 
which has such male terminals mounted in it; this structure is of a type 
disclosed in Japanese Utility Model Laying Open Publication Serial No. 
120576, which it is not intended hereby to admit as prior art to the 
present application except to the extent otherwise required by applicable 
law, and reference should be made to this publication, should further 
details be required. The base 101 is typically fixed to a board such as a 
printed circuit board or soldering or the like, and has a projection 102 
on its side, and the main body 103 of the connector has a lock piece 104 
integrally formed as projecting from its side, said lock piece 104 being 
formed with an engaging pawl shape 105 for engaging with the projection 
102 of the base 101, and for thus holding the body 103 of the connector 
squarely against said base 101 with the male terminals (not particularly 
shown) of said base 101 securely mating with the female terminals (also 
not shown). In detail, when performing the operation of fitting the body 
103 of the connector to the base 101, while said body 103 is being 
approached towards the base 101, a sloped side 105a of the pawl shape 105 
slides against a sloped side 102a of the projection 102, thereby somewhat 
bending the lock piece 104 against its elasticity and allowing the pawl 
shape 105 to pass over the projection 102. Thereafter, the inherent 
elasticity of the lock piece 104 keeps its pawl shape 105 pressed against 
and engaging with the projection 102, thus holding the body 103 of the 
connector squarely against the base 101. And, when it is desired to 
release the body 103 of the connector from the base 101, then typically 
said body 103 is forcibly pulled away from the base 101, and another 
sloped side 105b of the pawl shape 105 now slides against another sloped 
side 102b of the projection 102, thereby again somewhat bending the lock 
piece 104 against its elasticity and allowing the pawl shape 105 to pass 
back over the projection 102, to release the body 103 from the base 103. 
As an alternative, the lock piece may be bent back by hand or by the end 
of a screw driver or the like, again against its own elasticity. 
However, certain problems arise with such conventional structures for an 
electrical connector, as follows. 
First, with reference to the structure of the connector itself as shown in 
FIG. 4 of the drawings, since the number of sheathed electrical wires to 
be connected to the terminals of the base board can vary dramatically, 
depending upon the type of electrical equipment used for each specific 
application or upon the location in which such equipment is to be fitted, 
several configurations for the terminals and for the corresponding 
insertion holes 5 have been adopted. Most typically, they have been 
arranged either in one row or in two parallel rows as shown in the FIG. 4 
example, although configurations employing even more rows have 
occasionally been utilized. An appropriate one of these configurations is 
required to be selected for each particular application. Accordingly, 
although in principle these two types of electrical connector are 
basically similar, nevertheless the number of component parts that are 
required to be made in order to fabricate a comprehensive line of 
connectors incorporating both single row and double row types becomes 
large, and, since it is required to form the parts for the double row 
housings and the parts for the single row housings for the two types of 
connector by different sets of metal dies, accordingly the work and cost 
of development and tooling are similarly increased. Further, stocking 
problems and parts management problems are made to be more troublesome. 
Another problem is that, when the sheathed electrical wires are connected 
to the female terminals received inside the housing by crimping with a 
tool as is typical, different crimping tools are required to be utilized 
for double row housing type connectors and single row housing type 
connectors, and this is troublesome for the user. 
Next, with reference to the locking mechanism for fixing the connector to a 
base as shown in FIG. 8 of the drawings, the problem with this is that 
after a long period of service life and many repeated matings and 
separatings of the connector main body 103 to the base 101, and 
accompanying bendings to and fro of the lock piece 4, this lock piece 4 
may well lose its elasticity due to fatigue, with the result that the 
locking mechanism may fail in its function. And, because conventionally 
the lock piece 4 is integrally molded with the main body 3 of the 
connector, when the lock piece 4 has thus become ineffective for locking, 
it has heretofore been necessary to change the entire connector in order 
to remedy this locking problem, which is very troublesome and usually 
would be neglected by a user, with consequent risk of poor connection 
problems occurring. 
SUMMARY OF THE INVENTION 
Accordingly, it is the primary object of the present invention to provide 
an electrical connector, which avoids the above described problems. 
It is a further object of the present invention to provide such an 
electrical connector, which is adaptable to being easily manufactured in 
several configurations. 
It is a further object of the present invention to provide such an 
electrical connector, which reduces the number of different parts required 
for manufacture of a comprehensive line of configurations thereof. 
It is a further object of the present invention to provide such an 
electrical connector, which requires less tooling work for production of 
single row and double row configurations thereof. 
It is a further object of the present invention to provide such an 
electrical connector, which reduces overall development cost and work. 
It is a yet further object of the present invention to provide such an 
electrical connector, which reduces stock and parts management problems. 
It is a yet further object of the present invention to provide such an 
electrical connector, which allows a double row configuration thereof to 
be manufactured by utilizing the dies for making the single row 
configuration thereof and by combining the resulting single row 
connectors. 
It is a yet further object of the present invention to provide such an 
electrical connector, which reduces the number of crimping tools required 
to be provided by a user. 
It is a yet further object of the present invention to provide such an 
electrical connector, which has a locking mechanism which is reliable over 
a long service life. 
It is a yet further object of the present invention to provide such an 
electrical connector, which further has a locking mechanism the part of 
which is subject to wear can easily be replaced. 
It is a yet further object of the present invention to provide such an 
electrical connector, the locking mechanism of which is easily 
assemblable. 
According to the present invention, these and other objects are 
accomplished by an electric connector, comprising: a housing formed with a 
single row of holes for receiving male terminals and for receiving ends of 
sheathed wires connected thereto; and further formed with: means for, if 
and when two of said housings are laid together with their two said single 
rows of holes substantially aid housings are laid together with their two 
said single rows of holes substantially parallel, locating them with 
respect to one another with respect to mutual sliding movement; and 
according to another aspect of the present invention, similarly these and 
other objects are accomplished by an electric connector for being engaged 
with a fixed base, comprising a main housing formed with an engagement 
aperture on its side, and a lock mechanism comprising a catch piece formed 
with: a bent intermediate portion; a protruding press portion; a 
protruding engaging portion, formed with a catch shape for engaging with 
said fixed base; and an elastic fixing tongue engaged into said engagement 
aperture so as elastically to support said catch piece on the side of said 
main housing with said bent portion pressing against said main housing and 
acting as a fulcrum, and in this state biasing said protruding press 
portion in the direction away from said main housing and said protruding 
engaging portion in the direction towards said main housing. 
According to the first of these aspects of the present invention, since it 
is possible either to utilize such a single row housing on its own, or to 
utilize two or even more of such housings as laid together and mutually 
located by said locating means, therefore the number of different parts 
required for manufacture of a comprehensive line of configurations of 
connectors is substantially reduced over the prior art, because the only 
tools needed for parts production relate to production of the single row 
type connector housings, and typically also to coupling clips which are 
relatively simple to make. Thereby, less tooling work is required for 
production of single row and double row connector configurations, and 
overall development cost and work are reduced. Similarly, stock and parts 
management problems are reduced. Further, during the use of various ones 
of these connectors, both single and double row type, the same crimping 
tool can be used for coupling wires thereto, and accordingly the number of 
crimping tools required to be provided by a user is halved. And, according 
to the second of these aspects of the present invention, since the catch 
shape on the engaging portion is displaced away from the portion of the 
base that engages to it, when being moved past it, and is not required to 
slide over or to be forced over said engaging portion of the base either 
when the connector main body is being fitted to the base or when it is 
being removed therefrom either, there is virtually no wear on said catch 
shape or on said engaging portion of said base, and it is virtually 
impossible that either of them should become worn out with use. And 
further, when the elasticity of the tongue portion starts to fail because 
of repeated use over a long service life, it is quite easy to replace the 
catch piece by itself, which does not entail removing or otherwise 
adjusting the sheathed wires which are fitted to the connector main body. 
Thus according to this construction there is provided an electrical 
connector, which has a locking mechanism which is reliable over a long 
service life, and the part of which is subject to wear can easily be 
replaced. Further, this locking mechanism is easily assemblable.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The present invention will now be described with reference to the preferred 
embodiments thereof. FIG. 1 shows the first preferred embodiment of the 
present invention, which is a double row type connector made up by 
clipping together two single row type connectors back to back as will be 
explained hereinafter, said single row type connectors also being 
embodiments of the present invention. This figure, which is a perspective 
view, shows the connector in its assembled form, while FIG. 2 shows an 
exploded perspective view thereof. In these figures, the reference 
numerals 7a and 7b denote left and right ones of said single row type 
connectors, and covers 13a and 13b respectively are provided therefor. 
In detail, referring particularly to FIG. 2, the first single row connector 
7a will now be described; the other single row connector 7b is exactly the 
same but is positioned in a back to back orientation thereto with its two 
longitudinal ends reversed, and like parts therein to parts of the first 
connector 7a are denoted by the same reference numerals, but with a "b" 
affixed thereto instead of an "a". The single row connector 7a comprises a 
female terminal insertion portion 8a at its upper portion in the figures 
and a mating portion 60a at its lower portion in the figures. The female 
terminal insertion portion 8a of the connector 7a is formed with a single 
row of sheathed electrical wire insertion depressions 10a on its outer 
face 27a, and these depressions 10a open to a corresponding single row of 
wire connection holes 9a on the upper edge in the figures of the connector 
7a. The cover 13a, which is affixed by means shortly to be described, 
covers over the depressions 10a to leave only the connection hole 9a open. 
And the lower mating portion 60a of the connector 7a in the figures is 
formed, although this is not shown, with a corresponding plurality of male 
terminal receiving apertures, one opening to the end of each of the 
sheathed electrical wire insertion depressions 10a. Thus, these male 
terminal receiving apertures are also arranged in a single row upon the 
under edge (not shown) of the connector 7a. 
At each end of the cover 13a there is formed a projecting catch 14a with a 
tooth shape 14a1 at its end. At corresponding positions on the end faces 
37a of the female terminal insertion portion 8a of the connector 7a there 
are formed notches 11a with projections 12a therein. Thus, when the cover 
13a is approached to and pressed against the side of the connector 7a to 
cover the depressions 10a therein, the catches 14a fit into the notches 
11a, with the tooth shapes 14a1 engaging with the projections 12a, and 
thereby said cover 13a is securely held to the main body of the connector 
7a. 
Now, the arrangements for clipping together the two single row connectors 
7a and 7b will be described. This clipping is performed using two coupling 
clips 17, shown in FIG. 2 and one of which is also shown separately in 
perspective view in FIG. 3. This exemplary coupling clip 17 is made of 
relatively springy metal, in cross section is like a flattened C shape, 
and comprises a main body portion 19, two engaging portions 18 extending 
along opposite edges thereof and being bent around, the free edges of said 
edge portions 18 being formed with serrations, and a lock piece 20 formed 
integrally with the main body portion 19 in a cut out portion thereof, 
said lock piece 20 being somewhat bent out of the plane of said main body 
portion 19 in the direction of the engaging portions 18. Corresponding to 
these coupling clips 17, the outer side surface 47 of each of the single 
row connectors 7 is formed with engaging grooves 15 extending in the 
vertical direction in the figures along each of its end portions, and the 
lower portion in the figures of each of the end faces 37 of said 
connectors 7 is somewhat cut away and is further formed with a catch notch 
16 on its inner edge. Further, on the inner face 57 of each of the single 
row connectors 7a and 7b there are formed, at the one end a small 
engagement projection 21, and at the other end a corresponding small 
engagement depression 22. 
According to the above described first embodiment type structure, when it 
is desired to manufacture single row type connectors, only single ones of 
the single row type connectors 7a or 7b (which are identical) are 
manufactured and supplied. 
On the other hand, when it is desired to manufacture double row type 
connectors, then twice as many of the single row type connectors 7a or 7b 
are manufactured, and then they are connected together in pairs in the 
following way. First, two of said single row type connectors are put back 
to back, with the engagement projection 21 of each fitting into the 
engagement depression 22 of the other so as to locate them with respect to 
one another. Next, at each end of the resulting combination, one of the 
FIG. 3 type of coupling clips 17 is fitted thereto, by its two engaging 
portions 18 being slightly bent outwards (utilizing the elasticity of the 
metallic material of the clip) and the upper end of each then being 
inserted into the bottom as seen in the figure of one of the engaging 
grooves 15, and by the coupling clip 17 then being pushed in the upwards 
direction in the figure so as to slide over the lower portion of this end 
face 37 of the combined pair of connectors 7a and 7b. As this is done, 
initially the lock piece 20 is somewhat bent by being pressed against the 
end face 37, but when the lock piece 20 comes to oppose the mutually 
conjoined catch notches 16 on said end face 37, it snaps thereinto, 
thereby providing a retaining effect for the coupling clip 17, which 
thereafter is retained in this position by said lock piece 20, as well as 
by the action of the serrations formed on the free edges of the edge 
portions 18 of the engaging portions 18 of said clip 17. 
Thus, the two single row type connectors 7a and 7b are connected together 
as a pair, to constitute a double row type connector. Because the two 
single rows of sheathed electrical wire insertion depressions 10a on the 
outer faces 27a of these connectors 7a and 7b both face outwards, it is 
possible subsequently to affix sheathed electrical wires to the 
combination double row type connector in the same way as has been 
performed with conventional type double row type connectors. The way in 
which the covers 13a and 13b can be subsequently mounted to this conjoined 
pair of two single row type connectors 7a and 7b has already been 
implicitly explained, and is in fact no different from the way in which 
such a cover mounting process is performed in the case that one of the 
single row type connectors 7 is to be used by itself. 
Accordingly, it is seen that there is provided an electrical connector, 
which avoids the problems described above with respect to conventional 
art. Particularly, this electrical connector is adaptable to be easily 
manufactured in several configurations; indeed, it would not be 
impossible, or outside the scope of the present invention, for more than 
two of the single row type connectors 7 to be fixed together, in an 
alternative embodiment of the present invention. Accordingly, the number 
of different parts required for manufacture of a comprehensive line of 
configurations of connectors is substantially reduced over the prior art, 
because the only tools needed for parts production relate to production of 
the single row type connectors 7, and of course the coupling clips 17 
which are relatively simple to make. Thereby, less tooling work is 
required for production of single row and double row connector 
configurations, and overall development cost and work are reduced. 
Similarly, stock and parts management problems are reduced. Further, 
during the use of various ones of these connectors, both single and double 
row type, the same crimping tool can be used for coupling wires thereto, 
and accordingly the number of crimping tools required to be provided by a 
user is halved. 
Now, referring to FIGS. 5 through 7 of the drawings, a second preferred 
embodiment of the present invention will be explained. The gist of this 
second preferred embodiment relates to the provision of a novel type of 
locking mechanism for locking the connector main body to a base; 
accordingly, in these figures, the connector main body itself, which is a 
double row type of connector, is illustrated as monolithic, although in 
fact it may be made as two conjoined single row type connectors as 
described above with reference to the first preferred embodiment. FIG. 5 
shows the connector main body 120 along with its associated base assembly 
110 in perspective view with said main body 120 somewhat removed from said 
base assembly 110, while on the other hand FIG. 7 shows a side view of 
these elements as locked together by the locking mechanism. In detail, the 
base assembly 110 comprises a plurality of pins 112 arranged in two 
parallel rows and fixed to pass through a base plate 111, and, although 
this is not particularly shown, the lower portions in the figures of the 
pins 112 are inserted into holes formed in a printed circuit board and are 
soldered therein, so as firmly to hold the base assembly 110 to said 
printed circuit board with the upper ends of the pins 112 sticking up 
therefrom. 
The central portion of one side edge of the base plate 111 defines a 
clipping portion 113. 
The connector main body 120 is shown in FIG. 5 as substantially box shaped, 
and it may be of the type disclosed above, or it may be internally 
provided with fittings (not particularly shown) for connecting the pins 
112 of the base assembly 111 with surface projections and the external 
connection terminals of equipment such as a relay or a switch which are 
inserted from the surface portion. A catch fitting projection 121 is 
formed on a central portion of a lower edge of one side of the connector 
main body 120. In fact, one such catch fitting projection 121 may be 
provided on each side of the connector main body 120, to make two in all 
(this is typically the case when the connector main body is formed as 
described with respect to the first embodiment, and such a catch fitting 
projection is illustrated in FIGS. 1 and 2); and in such a case either two 
of the catch systems to be described shortly may be fitted, or 
alternatively only one may be fitted, and in that case one of the catch 
fitting projections 121 will be unused. The catch fitting projection 121 
is formed with a catch engagement hole 122 extending through it in the 
vertical direction in the figures. 
A catch piece 130 is formed as shown in perspective view in FIG. 5. It has: 
a main body portion 134; a press portion 130 extending at an oblique angle 
from said main body portion 134, and joined thereto at a bent joining 
portion 135, which is formed with a roughened or serrated surface for easy 
pressing; a fitting tongue portion 131 formed in a cutaway in the 
approximate center of said main body portion 134; and a catch ledge 132 
extending along the edge of the main body portion 134 remote from the bent 
joining portion 135. This catch piece 130 is formed of a relatively 
elastic material, so that, particularly, the fitting tongue portion 131 is 
quite elastic. The width of said fitting tongue portion 131 is 
approximately the same as the width of the catch engagement hole 122 
formed through the catch fitting projection 121. 
This catch piece 130 is fitted to the main body 120 of the connector, as 
shown in FIGS. 6 and 7, by its fitting tongue portion 131 being inserted 
from above (in the figures) into the catch engagement hole 122 of the 
catch fitting projection 121 and slid thereinto so as to be firmly lodged 
therein. In this position, the elasticity of said tongue portion 131 
biases the catch piece 130 as a whole in the clockwise direction as seen 
in FIG. 6, to its position as shown in that figure by the solid lines, so 
as to press the main body portion 134 and particularly the catch ledge 132 
formed thereon towards said connector main body 120 while biasing the 
press portion 130 away from said connector main body 120 so as to cause it 
to project therefrom. 
As will be easily understood based upon the foregoing explanation, when a 
user wishes to fit the connector main body 120 to the base assembly 110, 
he or she merely needs to press with his or her finger said press portion 
130 of the catch piece 130 towards said connector main body, so as to tilt 
the entire catch piece 130 as a whole in the anticlockwise direction as 
seen in FIG. 6 around the bent joining portion 135 which acts as a fulcrum 
to its position as shown in that figure by the phantom lines, against the 
elastic action of the tongue portion 131 which is overcome, which causes 
the main body portion 134 and particularly the catch ledge 132 formed 
thereon to be moved away from said connector main body 120. This can be 
accomplished with a simple pinching action, by only squeezing the 
connector body as a whole between thumb and forefinger. In this state, 
said connector main body 120 can easily be fitted to the base assembly 
110, with the pins 112 passing into the holes (not shown) of said 
connector main body 120, while the catch ledge 132 of the catch piece 130 
easily passes over the clipping portion 113 of the base plate 111. Then, 
the user releases this pressing of the press portion 130, which allows the 
elastic action of the tongue portion 131 to now rotate the catch piece 130 
as a whole in the clockwise direction as seen in FIG. 6 to its position as 
shown in that figure by the solid lines, thus biasing the main body 
portion 134 of the catch piece 130 and particularly the catch ledge 132 
formed thereon towards said connector main body 120. This allows the catch 
ledge 132 to become engaged with the clipping portion 113 of the base 
plate 111, so as securely to retain the connector main body 120 on the 
base assembly 110. 
And, when removing the connector main body 120 from the base assembly 110, 
this procedure needs merely to be reversed: the user again presses with 
his or her finger the press portion 130 of the catch piece 130 towards 
said connector main body 120, so as to tilt the catch piece 130 in the 
anticlockwise direction as seen in FIG. 6 to its position as shown in that 
figure by the phantom lines against the elastic action of the tongue 
portion 131 which is overcome, thus causing the main body portion 134 and 
the catch ledge 132 formed thereon to be again moved away from said 
connector main body 120. In this state, said connector main body 120 can 
easily be removed from the base assembly 110, while the catch ledge 132 of 
the catch piece 130 again easily passes over the clipping portion 113 of 
the base plate 111. Then, the user releases this pressing of the press 
portion 130, to release the connector main body 120. 
The roughened or serrated surface formed on the press portion 130 is 
convenient for aiding this pressing by the user's finger and for slippage 
prevention. 
In this shown second preferred embodiment of the present invention, in 
contrast to the prior art construction described above and shown in FIG. 
8, since the catch ledge 132 is displaced away from the clipping portion 
113 of the base plate 111 when being moved past it, and is not required to 
slide over or to be forced over said clipping portion 113 either when the 
connector main body 120 is being fitted to the base assembly 110 or when 
it is being removed thereform either, there is virtually no wear on said 
catch ledge 132 or on said clipping portion 113 of said base plate 111, 
and it is virtually impossible that they should become worn out with use. 
And further, when the elasticity of the tongue portion 131 starts to fail 
because of repeated use over a long service life, it is quite easy to 
replace the catch piece 130 by itself, which does not entail removing or 
otherwise adjusting the sheathed wires (not shown) which are fitted to the 
connector main body 120. Accordingly it is seen that according to this 
second preferred embodiment of the present invention there is provided an 
electrical connector, which has a locking mechanism which is reliable over 
a long service life, and the part of which is subject to wear can easily 
be replaced. Further, this locking mechanism is easily assemblable. 
Although the present invention has been shown and described in terms of 
certain preferred embodiments thereof, and with reference to the appended 
drawings, it should not be considered as being particularly limited 
thereby. The details of any particular embodiment, or of the drawings, 
could be varied without, in many cases, departing from the ambit of the 
present invention. Accordingly, the scope of the present invention is to 
be considered as being delimited, not by any particular perhaps entirely 
fortuitous details of the disclosed preferred embodiments, or of the 
drawings, but solely by the legitimate and properly interpreted scope of 
the accompanying claims, which follow.