Connector having core and insert-molded terminal

A connector includes a housing having an accommodating chamber formed in a connector-engaging direction and a first locking element formed in the accommodating chamber. A core is made of resin and accommodates an insert-molded terminal, and includes a second locking element which engages the first locking element in the accommodating chamber. The core is held in the accommodating chamber due to the engagement between the first locking element and the second locking element. A locking wall projecting in the accommodating chamber locks an end of the core.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a connector and more particularly to a 
connector, the housing of which holds a core made of resin and 
accommodating an insert-molded terminal so as to prevent the terminal from 
being shaken and removed from the housing and in addition, reduce the 
length of the housing in a terminal-inserting direction. 
2. Description of the Related Arts 
Art example of a conventional connector of this kind disclosed in Japanese 
Laid-Open Utility Model Publication No. 64-7777 is described below with 
reference to FIG. 24. A lance 3 comprising an elastic arm 3a and a locking 
projection 3b formed at the leading end of the elastic arm 3a is provided 
in an accommodating chamber 2 of a housing 1. The lance 3 locks a terminal 
4 in the accommodating chamber 2. 
In the above-described connector, when the terminal 4 is inserted into the 
accommodating chamber 2 from the rear side thereof as shown by an arrow 
(A) of FIG. 24, the elastic arm 3a is elastically flexed by the terminal 
4. When the terminal 4 has been moved further into the accommodating 
chamber 2, the locking projection 3b of the lance 3 is engaged by a 
locking opening 4a of the terminal 4 as shown by an arrow (C) of FIG. 24. 
In this manner, terminal 4 is held in the accommodating chamber 2. 
In the construction in which the terminal 4 is locked by the elastic lance 
3, there is a possibility that the terminal 4 is shaken or removed from 
the accommodating chamber 2 when an external force such as tensile force 
is applied to an electric wire connected with the terminal 4. 
It is necessary for the elastic arm 3a to have a considerable length (L) to 
allow the lance 3 to be elastic. As a result, the housing 1 is necessarily 
long in a terminal-inserting direction. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a connector which 
prevents a terminal held in a housing from being shaken or removed 
therefrom. 
It is another object of the present invention to provide a connector in 
which the length of the housing is short in a terminal-inserting 
direction. 
In accomplishing these and other objects, there is provided a connector 
comprising: a housing having an accommodating chamber formed in a 
connector-engaging direction and first locking means formed in the 
accommodating chamber; and a core, made of resin and accommodating an 
insert-molded terminal, comprising second locking means which engages the 
first locking means of the accommodating chamber. The core is held in the 
accommodating chamber due to the engagement between the first locking 
means and the second locking means. 
A locking wall projecting in the accommodating chamber locks an end of the 
core inserted into the accommodating chamber in a predetermined direction. 
The first locking means consists of a locking projection formed on an inner 
peripheral surface of the accommodating chamber. The second locking means 
consists of a locking groove formed on a peripheral surface of the core. 
According to the above-described construction, the locking projection, 
namely, the first locking means is formed in the accommodating chamber 
formed in the connector-engaging direction of the housing. The locking 
groove, namely, the second locking means is formed on the peripheral 
surface of the core, made of resin, accommodating an insert-molded 
terminal. The locking groove engages the locking projection of the 
accommodating chamber. In this manner, the core is held in the 
accommodating chamber. The locking wall formed in the accommodating 
chamber locks the end of the core inserted into the accommodating chamber 
in the predetermined direction. Accordingly, when an external force such 
as tensile force is applied to an electric wire connected with the 
terminal, the terminal can be prevented from being shaken and removed from 
the housing. 
In addition, the core accommodating the insert-molded terminal is held in 
the housing due to the engagement between the locking projection of the 
housing and the locking groove of the core. Therefore, it is unnecessary 
to form a lance in the housing. As a result, it is unnecessary to elongate 
the housing in the terminal inserting direction thereof, unlike the 
conventional connector requiring the lance which necessitates the 
elongation of the housing.

DETAILED DESCRIPTION OF THE INVENTION 
Before the description of the present invention proceeds, it is to be noted 
that like parts are designated by like reference numerals throughout the 
accompanying drawings. 
A connector according to an embodiment of the present invention is 
described below with reference to FIGS. 1 through 23. 
A connector shown in FIGS. 1 through 6 comprises a female connector 23 and 
a male connector 24 connected to each other so as to connect a female 
terminal 21 of the female connector 23 and a male terminal 22 of the male 
connector 24 to each other. 
In the female connector 23, a female core 27 made of resin is inserted into 
a female housing 26 made of resin. The female core 27 accommodates the 
insert-molded female terminal 21. A closing member 28 closes one end of 
the female housing 26. The closing member 28 is described later. 
As shown in detail in FIGS. 6 through 10, the female housing 26, 
sectionally rectangular and cylindrical, comprises a female terminal 
accommodating chamber 29 and a rubber ring accommodating chamber 30 
continuous with the female terminal accommodating chamber 29. The chambers 
29 and 30 are formed from the front end surface 26a, of the female housing 
26, at which the female connector 23 engages the male connector 24 toward 
the rear end surface 26b of the female housing 26. The female terminal 
accommodating chamber 29 and the rubber ring accommodating chamber 30 are 
sectionally circular. A pair of locking walls 31 and 31 is formed at the 
connecting portion between the female terminal accommodating chamber 29 
and the rubber ring accommodating chamber 30. 
A pair of locking projections 32 and 32 opposed to each other is formed in 
the rear side of an inner peripheral surface 29a of the female terminal 
accommodating chamber 29. The locking projections 32 and 32 constituting a 
first locking means engages a locking groove 27e of a core 27 which will 
be described later. 
The locking projections 32 comprises an inclined portion 32a inclining with 
respect to the inner peripheral surface 29a; a flat portion 32b almost 
parallel with the inner peripheral surface 29a; and an engaging portion 
32c almost perpendicular to the inner peripheral surface 29a. These 
members 32a, 32b, and 32c are continuous with each other and formed in the 
direction from the front side (X). 
Referring to FIGS. 8 through 10, a pair of core guide grooves 33 and 33 
opposed to each other is formed on the inner peripheral surface 29a of the 
female terminal accommodating chamber 29. The core guide grooves 33 and 33 
are sectionally rectangular and extend along the entire female terminal 
accommodating chamber 29 in the longitudinal direction thereof. 
Referring to FIGS. 4 and 5, the sectional area of the rubber ring 
accommodating chamber 30 is greater than that of the female terminal 
accommodating chamber 29 so that an annular second rubber ring 34 is 
inserted into the rubber ring accommodating chamber 30. 
As shown in FIGS. 9 and 10, the peripheral wall of the female housing 26 
has a double construction in the front side (X) thereof so as to form a 
gap 36 between an inner wall of the female housing 26 and an outer wall 
26d thereof. The male housing 45 of the male connector 24 is inserted into 
the gap 36. 
A pair of cut-out openings 26e and 26e opposed to each other is formed in 
the rear side (Y) of the outer wall 26d. A pair of projections 37a and 37a 
(see FIG. 5) formed on the peripheral surface of an annular second rubber 
ring 37 (see FIGS. 4 and 5) is locked by each of the cut-out openings 26e 
and 26e, thus holding the second rubber ring 37 in the gap 36. 
Rectangular guide plates 38 and 38 (see FIGS. 6, 7, 8A and 8B) opposed to 
each other and integral with the female housing 26 is formed on an upper 
portion of the outer wall 26d of the female housing 26. The guide plates 
38 and 38 are disposed in the front side (X) of the female housing 26. The 
front end portion of the outer wall 26d is folded back toward the rear 
side (Y) to form a locking elastic arm 39 (see FIGS. 4, 6, 7, and 9) 
between the guide plates 38 and 38. 
The elastic arm 39 is elastically flexed, with the front end portion of the 
outer wall 26d serving as the fulcrum of the flexure. A locking projection 
39a (see FIGS. 6, 7, and 9) which engages a locking opening 45g (see FIGS. 
2, 16, and 18) formed on the male housing 45 of the male connector 24 is 
formed in the vicinity of the center of the elastic arm 39 in the 
longitudinal direction thereof, and a pressing portion 39b (see FIGS. 6, 
7, and 9) is formed in the rear end of the elastic arm 39. The locking 
opening 45g will be described later. 
A pair of locking projections 41 and 41 (FIGS. 5, 6, and 8) which engages 
each of a pair of locking openings 28d and 28d of the closing member 28 is 
formed in the vicinity of the rear end of the female housing 26. Each 
projection 41 is interposed between a pair of rectangular guide plates 42 
and 42. 
As shown in detail in FIGS. 11 through 14, the female core 27 made of 
insulating resin accommodates the insert-molded female terminal 21. 
The female terminal 21 made of a conductive material such as copper 
comprises a cylindrical portion 21a (see FIG. 14) into which a leading end 
22c (see FIG. 20) of the male terminal 22 is inserted. The cylindrical 
portion 21a is disposed in the front side (X) of the female terminal 21. 
The female terminal 21 further comprises a core wire crimping portion 21b 
of a small diameter and a coating crimping portion 21c of a large 
diameter. The core wire crimping portion 21b is continuous with the 
cylindrical portion 21a. The core wire crimping portion 21b crimps a core 
wire 44a of an electric wire 44 while the coating crimping portion 21c 
continuous with the core wire crimping portion 21b crimps the coating 
portion of the electric wire 44. 
The female terminal 21 is insert-molded in the female core 27, with the 
core wire 44a and the coating portion 44b crimped by the core wire 
crimping portion 21b and the coating crimping portion 21c, respectively. 
Referring to FIG. 14, the cylindrical female core 27 comprises a first 
large-diameter portion 27a accommodating the cylindrical portion 21a of 
the female terminal 21; a small-diameter portion 27b accommodating the 
core wire crimping portion 21b; and a second large-diameter portion 27c 
accommodating the coating crimping portion 21c. The outer diameter of the 
first large-diameter portion 27a and that of the second large-diameter 
portion 27c are set so that the first large-diameter portion 27a and the 
second large-diameter portion 27c are slidable in close contact with the 
inner peripheral surface 29a of the female terminal accommodating chamber 
29. 
Referring to FIGS. 11 and 12, a locking groove 27e, sectionally 
rectangular, serving as a second locking means is circumferentially formed 
in the vicinity of the rear end surface 27d of the second large-diameter 
portion 27c. The end surface 27d is circumferentially chamfered to form an 
inclined portion 27f. 
There is formed, on the peripheral surface of the female core 27, a pair of 
guide plates 27g and 27g (see FIGS. 11, 12, 13A, and 13B) opposed to each 
other and extending from the front end surface 27h of the female core 27 
toward the rear end thereof. 
A pair of protecting walls 27k and 27k (see FIG. 13A) projects from the 
front end surface 27h of the female core 27 in such a manner that the 
cylindrical portion 21a of the female terminal 21 projecting from the 
front end surface 27h is interposed between the protecting walls 27k and 
27k. 
Referring to FIGS. 1, 3A, and 3B, the closing member 28 which is 
approximately rectangular and closes the rubber ring accommodating chamber 
30 comprises a plate 28b on which a cut-out 28a (see FIG. 3A) is formed 
and a pair of locking arms 28c and 28c disposed at both sides of the plate 
28b. A pair of locking openings 28d and 28d is formed on each of the 
locking arms 28c and 28c. 
In the female connector 21, the first rubber ring 34 and the second rubber 
ring 37 are disposed in the rubber ring accommodating chamber 30 of the 
female housing 26 and the gap 36 thereof, respectively. Then, the female 
core 27 is inserted into the female terminal accommodating chamber 29 from 
the front end 26a, of the female housing 26, at which the female connector 
23 engages the male connector 24, with the guide plates 27g and 27g of the 
female core 27 coinciding with each of the guide grooves 33 and 33 of the 
female housing 26. 
As a result, the locking projection 32 of the female housing 26 is inserted 
into the locking groove 27e of the female core 27, and the locking portion 
32c of the locking projection 32 engages a side wall 27m disposed rearward 
of the locking groove 27e. In this manner, the female core 27 is locked in 
the female housing 26. The rear end surface 27d of the female core 27 is 
locked by the locking walls 31 and 31 of the female housing 26. 
Since the female core 27 is guided by the guide groove 33 as described 
previously, the female core 27 can be smoothly inserted into the female 
terminal accommodating chamber 29. The inclined surface 27f is formed on 
the rear end surface of the female core 27. Therefore, the inclined 
portion 32a (see FIG. 9) of the locking projection 32 formed in the female 
terminal accommodating chamber 29 engages the inclined surface 27f. In 
this manner, the locking projection 32 can be smoothly engaged by the 
locking groove 27e. 
Thereafter, the electric wire 44 extending from the rear end of the female 
housing 26 is introduced into the cutout 28a (see FIG. 3A), and both sides 
of the locking arm 28b (see FIG. 3B) is inserted between the guide plates 
42 and 42 disposed in the rear end of the female housing 26. Then, the 
locking projection 41 of the female housing 26 is engaged by the locking 
opening 28d (see FIG. 1) of the locking arm 28c. In this manner, the 
closing member 28 is fixed to the rear end of the female housing 26. 
In the female connector 23, the female core 27 accommodating the 
insert-molded female terminal 21 is inserted into the female housing 26 
from the connector-engaging side (front side) thereof, and the rear end 
27d of the female core 27 is locked by the locking wall 31 formed in the 
female housing 26. Accordingly, when an external force such as tensile 
force is applied to the electric wire 44, the female terminal 21 can be 
prevented from being shaken and removed from the female housing 26. 
In the female connector 23, the female core 27 is held in the female 
housing 26 by the engagement between the locking groove 27e of the female 
core 27 and the locking projection 32 formed in the female terminal 
accommodating chamber 29 of the female housing 26. This way of connecting 
the female terminal 21 to the female housing 26 eliminates the need for 
elongating the female connector 23 in the terminal-inserting direction 
thereof unlike the conventional connector in which the terminal is locked 
by the lance provided in the housing. 
In the male connector 24, a male core 46 (see FIGS. 20 through 23), made of 
resin, accommodating the insert-molded male terminal 22 is inserted into 
the male housing 45 made of resin, and one end of the male housing 45 is 
closed by the closing member 28, similarly to the female connector 23. 
As shown in detail in FIGS. 15 through 19, the cylindrical male housing 45 
comprises a connector engaging portion 47 (see FIGS. 18 and 19) extending 
from the front end surface 45a of the male housing 45 toward the rear 
portion thereof; a male terminal accommodating chamber 48; and a rubber 
ring accommodating chamber 49 disposed in the rear region of the male 
housing 45. The connector engaging portion 47, the male terminal 
accommodating chamber 48, and the rubber ring accommodating chamber 49 are 
continuous with each other and sectionally circular. The diameter of the 
connector engaging portion 47 is set to be equal to that of the rubber 
ring accommodating chamber 49 while the diameter of the male terminal 
accommodating chamber 48 is set to be smaller than those of the connector 
engaging portion 47 and the rubber ring accommodating chamber 49. A pair 
of locking walls 50 and 50 (see FIGS. 17B and 19) for locking the male 
core 46 projects from the connecting portion disposed between the male 
terminal accommodating chamber 48 and the rubber ring accommodating 
chamber 49. 
A pair of locking projections 52 and 52 (see FIGS. 17A, 18, and 19) opposed 
to each other is formed in the rear side of an inner peripheral surface 
48a of the male terminal accommodating chamber 48. The locking projections 
52 and 52 constituting a first locking means lock a locking groove 46e of 
the male core 46 which will be described later. 
The locking projection 52 comprises an inclined portion 52a inclining with 
respect to the inner peripheral surface 48a; a flat portion 52b almost 
parallel with the inner peripheral surface 48a; and an engaging portion 
52c almost perpendicular to the inner peripheral surface 48a. These 
members 52a, 52b, and 52c are continuous with each other and formed in the 
direction from the front side (X') of the male housing 45 toward the rear 
side Y' thereof. 
A pair of sectionally rectangular core guide grooves 53 and 53 (see FIG. 
17B) forming a right angle with each other is formed on the inner 
peripheral surface 48a of the terminal accommodating chamber 48. The core 
guide grooves 53 and 53 extend along the terminal accommodating chamber 48 
in the longitudinal direction thereof as shown. A pair of guide plates 46f 
and 46f (see FIGS. 21 and 22) of the male core 46 is inserted into each of 
the guide grooves 53 and 53. 
Similarly to the female connector 23, the annular first rubber ring 34 (see 
FIGS. 4 and 5) is inserted into the rubber ring accommodating chamber 49. 
A sectionally rectangular locking arm inserting portion 54 (see FIGS. 17B 
and 18) is formed on an upper portion of an outer wall 45c (see FIG. 18) 
disposed at the front side X' of the male housing 45. The locking arm 
inserting portion 54 is open in only the front side X' and surrounded with 
right and left side walls 45d and 45d, an upper wall 45e, and a rear wall 
45f. A locking opening 45g (see FIGS. 16 and 18) which engages the locking 
projection 39a (see FIGS. 6, 7, and 9) formed on the locking arm 39 of 
the female connector 23 is formed on the upper wall 45e. 
The peripheral surface of the connector engaging portion 47 is thin in the 
vicinity of the leading end thereof to form an inserting portion 45h. 
A pair of locking projections 55 and 55 (see FIGS. 15, 16, 17A, and 19), 
opposed to each other, which engages the locking openings 28d of the 
closing member 28 is formed on the peripheral surface of the male housing 
45 at a position disposed in the vicinity of the rear end thereof. The 
projection 55 is interposed between a pair of guide plates 56 and 56 (see 
FIGS. 15 and 17A) disposed at the rear end of the male housing 45. 
As shown in detail in FIGS. 20 through 23, the male terminal 22 
insert-molded in the male core 46 made of insulating resin is made of a 
conductive material. There is formed, at the front end of the male 
terminal 22, a connecting portion 22c (see FIGS. 20 and 23) comprising 
forked cylindrical portion 22b having a spherical portion 22a formed at 
the leading end thereof. A core wire crimping portion 22e (see FIG. 23) is 
formed in continuation with the connecting portion 22c via a flange 
portion 22d (see FIG. 23), and a coating crimping portion 22f is formed in 
continuation with the core wire crimping portion 22e. 
The male terminal 22 is insert-molded in the male core 46, with the core 
wire 44a and the coating portion 44b crimped by the core wire crimping 
portion 22f and the coating crimping portion 22e, respectively. The flange 
portion 22d and the connecting portion 22c project from a flange-shaped 
portion 46a (see FIGS. 20 and 21), of a large diameter, formed on the 
front end of the male core 46. A pair of protecting plates 46b and 46b 
(see FIGS. 21 and 23) opposed to each other is formed on the flange-shaped 
portion 46a in such a manner that the leading end of the protecting plates 
46b and 46b extends to the vicinity of the center of the connecting 
portion 22c in the longitudinal direction thereof. 
The male core 46 comprises a small diameter portion 46b in which the core 
wire crimping portion 22e of the male terminal 22 is insert-molded and a 
large-diameter portion 46c in which the coating crimping portion 22f 
thereof is insert-molded. The small diameter portion 46b and the 
large-diameter portion 46c are continuously formed and disposed rearward 
of the flange-shaped portion 46a. The outer diameter of the large-diameter 
portion 46c is set so that the large-diameter portion 46c is slidable in 
close contact with the terminal accommodating chamber 48 of the male 
housing 45. 
A sectionally rectangular engaging groove 46e (see FIGS. 20, 21, and 23) 
serving as a second locking means is circumferentially disposed in the 
vicinity of the rear end surface 46d of the large-diameter portion 46c. 
The end surface 46d is circumferentially chamfered to form an inclined 
portion 46f. 
Guide plates 46f and 46f (see FIGS. 20, 21, 22A, and 22B) making a right 
angle with each other and extending from the front side X' of the male 
core 46 toward the rear side Y' thereof are formed on the peripheral 
surface thereof. 
The closing member 28 mounted on the rear end of the male housing 45 has a 
construction similar to the closing member 28 of the female connector 23. 
Therefore, the description of the closing member 28 of the male housing 45 
is omitted herein. 
In the male connector 24, similarly to the female connector 23, the male 
core 46 is inserted into the male housing 45 from the front side X' 
thereof after the rubber ring 34 is inserted into the male housing 45, 
with the guide plates 46f and 46f coinciding with each of the core guide 
grooves 53 and 53. Then, the locking projection 52 is engaged by the 
locking groove 46e of the male core 46 so as to hold the male core 46 in 
the male housing 45. Thereafter, the closing member 28 is installed on the 
rear end of the housing 45. 
In the male connector 24, similarly to the female connector 23, the end 
surface 46d disposed in the rear end of the male core 46 inserted into the 
male housing 45 from the front side thereof is locked by the locking wall 
50 of the male housing 45. Accordingly, the male terminal 22 can be 
prevented from being shaken and removed from the male housing 45. The male 
terminal 22 can be held in the male housing 45 by the engagement between 
the locking groove 46e of the male core 46 and the locking projection 52 
of the male housing 45. Accordingly, it is unnecessary to elongate the 
male housing 45 in the terminal inserting direction thereof unlike the 
conventional connector in which the terminal is locked by the lance 
provided in the housing. 
In engaging the female connector 23 with the male connector 24, both 
connectors approach to each other so that the locking elastic arm 39 of 
the female connector 23 is inserted into the locking arm inserting portion 
54 of the male connector 24. At this time, the guide plates 38 and 38 
formed on the female connector 23 guide the locking arm inserting portion 
54 along the inner surface of the side walls 45d and 45d, and the 
inserting portion 45a of the male connector 24 disposed at the front end 
thereof is inserted into the gap 36 of the female connector 23. In this 
manner, both connectors 23 and 24 can smoothly approached each other. 
As a result, the connecting portion 22c of the male terminal 22 is inserted 
into the cylindrical portion 21a of the female terminal 21. Consequently, 
the female terminal 21 and the male terminal 22 are connected to each 
other. At this time, the locking projection 39a formed on the locking 
elastic arm 39 of the female connector 23 engages the locking opening 45g 
of the male connector 24. Consequently, the connectors 23 and 24 are 
locked to each other. 
At this time, the inserting portion 45a of the male connector 24 is 
inserted into the second rubber ring 37 of the female connector 23, which 
ensures the connection between the connectors 23 and 24. 
Various modification of the connector according to the present invention 
can be made as follows: 
In both male and female connectors, the housing holds the core, made of 
resin, accommodating the insert-molded terminal, but this construction may 
be adopted in either the male connector or in the female connector, i.e., 
one of the terminals may be held by a lance provided in the housing 
without using the core. 
Either the female connector or the male connector may be held in the 
connector according to the embodiment while the other terminal is disposed 
in a junction box. That is, the female connector is not necessarily 
connected with the male connector and the male connector is not 
necessarily connected with the female connector. 
The configuration of the housing and that of the core are not limited to 
those of the embodiment. For example, the core accommodating the 
insert-molded terminal is inserted into the accommodating chamber of the 
housing formed in the direction in which female connector is engaged by 
the male connector, and locking means formed both in the accommodating 
chamber and in the core are locked to each other. 
Although the present invention has been fully described in connection with 
the preferred embodiments thereof with reference to the accompanying 
drawings, it is to be noted that various changes and modifications are 
apparent to those skilled in the art. Such changes and modifications are 
to be understood as included within the scope of the present invention as 
defined by the appended claims unless they depart therefrom.