Information
-
Patent Grant
-
6290521
-
Patent Number
6,290,521
-
Date Filed
Monday, April 10, 200024 years ago
-
Date Issued
Tuesday, September 18, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Sircus; Brian
- Nguyen; Son V.
Agents
-
CPC
-
US Classifications
Field of Search
US
- 439 189
- 439 595
- 439 511
- 439 752
-
International Classifications
-
Abstract
A connector for electrical terminals includes a housing that has a plurality of cavities, a plurality of respective resiliently deformable locking members, and a plurality of respective terminals. Each terminal is inserted in a respective cavity and has (a) a partially inserted position in which the terminal bears on the respective locking member to deform the locking member so that the locking member is raised with respect to a peripheral surface of the housing, and (b) a fully inserted position in which the locking member snap-fits to the terminal thereby locking the terminal in said cavity. The connector further includes a bus bar holder having a sleeve which accommodates a plurality of bus bar tab pieces. The sleeve is push-fitted over the peripheral surface of the housing to install the bus bar holder to the housing and to contact the tab pieces to the terminals, whereby the terminals are electrically connected to each other. Each locking member has an end surface portion which is adapted so that when, on push-fitting of the sleeve, a terminal is in the partially inserted position with the respective locking member raised with respect to the peripheral surface of the housing, the sleeve bears on the end surface portion to prevent installation of the bus bar holder.
Description
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a connector, particularly a connector for use in the wiring of a vehicle such as an automobile.
2. Description of Related Art
A connector disclosed in Japanese Patent Application Laid-Open No. 9-213436 is described below. The connector has a housing into which a plurality of terminals are inserted from a rear portion thereof and a bus bar holder in which a holding member holds a plurality of bus bars each of which has a tab piece projecting from a side edge of a belt-shaped carrier. The bus bar holder is inserted into an opening at the front surface of the housing to connect the tab pieces with the terminals. In this manner, the terminal fittings are electrically connected to each other.
It is also known to lock the terminals into a position in the housing with a plurality of respective locking lances. Theses lances may project outwardly from the housing if the terminals are not fully inserted.
The tab pieces project from the holding member of the bus bar holder and are externally exposed. Therefore, when the bus bar holder is packed in a bag or a box for delivery, or when it is installed to the housing, other bus bar holders may catch on the tab pieces. Thus, there is a risk that the tab pieces can be deformed or damaged.
To prevent such risk, it is known to use a bus bar holder having a protective cylindrical sleeve which accommodates the tab pieces. This construction has an advantage of helping to prevent the tab pieces from being deformed or broken.
Also, with this arrangement the bus bar holder is capable of detecting incomplete insertion of the terminals in the connector housing. When the terminals are fully inserted into the connector housing, the sleeve can be installed onto the housing without interfering with the locking members which hold the terminals in place. On the other hand, when any of terminals is not properly inserted into the connector housing, the respective locking member projects from the peripheral surface of the housing and collides with the end surface of the sleeve on installation. That is, the proper or improper insertion of the terminals can be detected by whether the sleeve interferes with the locking members.
However, when a projecting lance collides with the cylindrical sleeve, the lance may flex excessively, possibly breaking or damaging the lance.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to prevent a locking member or lance from flexing excessively when a bus bar holder is installed on a connector housing and the respective terminal is not properly inserted.
According to the present invention there is provided a connector for electrical terminals. The connector has a housing with a peripheral surface, a plurality of cavities, a plurality of resiliently deformable locking members, and a plurality of terminals. Each terminal is inserted in a respective cavity and has (a) a partially inserted position in which the terminal bears on the respective locking member to deform the locking member so that the locking member is raised with respect to a peripheral surface of the housing, and (b) a fully inserted position in which the locking member snap-fits to the terminal thereby locking the terminal in the cavity.
The connector also has at least one bus bar holder with a sleeve and a plurality of bus bar tab pieces which are accommodated in the sleeve. The sleeve is push-fitted over the peripheral surface of the housing to install said bus bar holder to the housing and to contact the said tab pieces to the terminals. In this way the terminals are electrically connected to each other.
Each locking member has an end surface portion which is inclined with respect to the push-fit direction of the sleeve. Therefore, when, on push-fitting of the sleeve, a terminal is in its partially inserted position with the respective locking member raised with respect to peripheral surface, the sleeve bears on the respective first end surface portion to urge the locking member toward the terminal. This prevents excess deformation of the locking member from occurring.
Each of the locking member may also have a second end surface portion which faces the first end surface portion and, with respect to the first end surface portion, is oppositely inclined with respect to the push-fit direction of the sleeve. In this way, when, on push-fitting of the sleeve, each terminal is in its partially inserted position with the respective locking member raised with respect to the peripheral surface, the sleeve also bears on the second surface portion to urge the locking member away from the terminal.
The first and second end surface portions may, for example, define a V-shaped recess in the respective locking members.
When the sleeve of the bus bar holder contacts both the first and the second end surface portions of a locking member, the locking member experiences opposing and balance forces on its end surface portions. These forces prevent it from being displaced either away from or toward the terminal. Thus the installation of the bus bar holder on the housing is prevented. That is, even though the bus bar holder is urged strongly against the locking member, the locking member is prevented from being forcibly displaced in a direction which would remove its elastic deformation. Therefore, the locking member is prevented from being pressed against the terminal with an excessive force and possibly being damaged.
Preferably, the angle of inclination of the first end surface portion with respect to the push-fit direction of the sleeve is smaller than the angle of inclination of the second end surface portion with respect to the push-fit direction when the sleeve bears on both the first and second end surface portions.
With this arrangement, the force applied to a locking member by the sleeve in the direction which would remove its elastic deformation (i.e. toward the terminal) is greater than the force applied in the direction which would increase its elastic deformation (i.e. away from the terminal). Accordingly, it is possible to avoid excess flexing and deformation of the locking member.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of this invention will be described in detail by way of non-limitative example with reference to the following drawings, in which:
FIG. 1
is a perspective view of a housing of a connector according to the invention;
FIG. 2
is a partly cut-away perspective view of bus bar holders that engage the housing, seal member and seal holder of
FIG. 1
;
FIG. 3
is a perspective view of a cap that covers the housing of FIG.
1
and the bus bar holders of
FIG. 2
;
FIG. 4
is a sectional view of the connector in an engagement state on plane I—I of
FIG. 1
, plane II—II of FIG.
2
and plane III—III of
FIG. 3
;
FIG. 5
is a sectional view on plane I—I of
FIG. 1
, showing a sealing member and a seal holder installed on the housing;
FIG. 6
is a sectional view on plane II—II of
FIG. 2
;
FIG. 7
is a sectional view on plane III—III of
FIG. 3
;
FIG. 8
is an enlargement of a part of the sectional view of
FIG. 4
, showing a terminal fully inserted into the housing;
FIG. 9
is the same view as
FIG. 8
except that the terminal is partially inserted into the housing;
FIG. 10
is the same view as
FIG. 9
except that a locking lance of the housing is further deformed by a sleeve of the bus bar holder;
FIG. 11
is a partly cut-away plan view of the housing;
FIG. 12
is a rear view of the sealing member; and
FIG. 13
is a rear view of the seal holder.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A connector embodying the present invention is described in conjunction with
FIGS. 1
to
13
. The connector electrically connects a plurality of terminals
20
in a predetermined connection pattern with a bus bar
55
and includes a housing
10
, a plurality of the terminals
20
, a sealing member
30
, a seal holder
40
, two bus bar units
50
, and a cap
60
.
The housing
10
is made of a synthetic resinous material. As shown in
FIGS. 1 and 5
, the housing
10
may have cavities
11
arranged in upper and lower rows and extending through the housing
10
in a front-to-rear direction. In each of the upper and lower rows, the cavities
11
may be arranged widthwise at regular intervals. The front half regions of the upper-row cavities
11
and the lower-row cavities
11
are open at the upper and lower surfaces of the housing
10
, respectively. In each open portion, locking members, such as locking lances
12
, project forward in a cantilever manner. Between the upper and lower rows of the cavities
11
there is formed a wide recess
13
for allowing the peripheral walls of the bus bar units
50
, as described below, to penetrate. An upper surface wall and a lower surface wall of the recess
13
are partly cut away to allow communication with the cavities
11
.
The locking lances
12
retain and prevent the removal of the terminals
20
inserted into the cavities
11
. In cooperation with a cylindrical portion
53
of the bus bar unit
50
shown in
FIGS. 8-10
, locking the lances are also used for detecting the degree of insertion of the terminals
20
. The locking lances
12
can be outwardly elastically displaced relative to an outer surface
10
A of the housing
10
. As shown in
FIG. 8
, before a terminal
20
is inserted into a cavity
11
and after the terminal
20
is fully inserted therein, a corresponding locking lance
12
is undeformed, and an outer surface
12
A of the locking lance
12
is flush with the outer surface
10
A of the housing
10
. In this state, when the terminals
20
are fully inserted, a removal prevention projection
12
B formed at a front end of each locking lance
12
is engaged in a locking hole
24
of the terminal
20
, thus preventing removal of each terminal
20
. However, as shown in
FIG. 9
, when any of the terminals
20
are not fully inserted, the removal prevention projection
12
B interferes with the outer surface of a mating portion
21
of the terminal
20
. As a result, as described in
FIG. 10
, the locking lance
12
is elastically displaced such that its outer surface
12
A is located outwardly from the surface
10
A of the housing
10
. Therefore, when a bus bar unit
50
is installed on the housing
10
, the cylindrical portion
53
of the bus bar unit
50
collides with the front end of the locking lance
12
. This prevents the bus bar unit
50
from being installed on the housing
10
.
At the front-end surface of each locking lance
12
, there is formed an excess flexure prevention surface
12
C that prevents the locking lance
12
from flexing excessively beyond the limit of its elasticity, when the cylindrical portion
53
collides with the front end of the locking lance
12
. At the front-end surface of each locking lance
12
, there is also formed a balancing surface
12
D inclining in a direction opposite to the direction of inclination of the excess-flexure prevention surface
12
C. For example, in a side view, the front-end surface of the locking lance
12
may be recessed in the shape of a “V”, as shown in
FIGS. 8-10
. The inward side, i.e., the terminal side, of the front-end surface of the locking lance
12
is the excess-flexure prevention surface
12
C and the outer side of the front-end surface is the balancing surface
12
D.
While the surfaces
12
C and
12
D form a “V” shape in
FIGS. 8-10
, it will be appreciated that other shapes are possible. For example, the surfaces
12
C and
12
D may form a curved “U” shape, rather than being linear surfaces that form a “V”. Additionally, rather than two linear surfaces, one or more of the surfaces may be curved, and/or more than two surfaces may be provided at the end of each locking lance
12
.
While the locking lance
12
is elastically displaced within its elastic limit, an end surface of the cylindrical portion
53
collides with the excess-flexure prevention surface
12
C when each bus bar unit
50
is installed on the housing
10
. The excess-flexure prevention surface
12
C is so inclined that the excess-flexure prevention surface
12
C stops and reduces excess elastic deformation of the locking lance
12
, as best shown in FIG.
10
.
While the locking lance
12
is elastically displaced within its elastic limit, the cylindrical portion
53
is also capable of colliding with the balancing surface
12
D, when each bus bar unit
50
is installed on the housing
10
. The balancing surface
12
D is inclined so that the locking lance
12
is then urged in a direction in which the elastic displacement of the locking lance
12
increases (upward in
FIGS. 8
to
10
). Ultimately the cylindrical portion
53
contacts both the excess-flexure prevention surface
12
C and the balancing surface
12
D, as shown in FIG.
10
. Comparing the relative inclinations of the excess-flexure prevention surface
12
C and the balancing surface
12
D when both surfaces are in contact with the cylindrical portion
53
, as shown in
FIG. 10
, the acute angle α between the direction of insertion of the cylindrical portion
53
and the excess-flexure prevention surface
12
C is smaller than the angle β between the insertion direction the cylindrical portion
53
and the balancing surface
12
D.
Each terminal
20
is made of a metal plate material punched into a predetermined configuration. As shown in
FIG. 1
, the front half part of the terminals
20
may be formed as a square pillar-shaped mating portion
21
that is open forward and rearward. The rear half of the terminals
20
is formed as an electric wire connection portion
22
that may be crimped to the core of an electric wire
25
.
As shown in
FIG. 4
, a resilient contact piece
23
that contacts a connection piece
57
of a bus bar
55
is formed inside the mating portion
21
. A locking hole
24
which the locking lance
12
of the housing
10
engages is formed on a peripheral wall of the mating portion
21
. The terminals
20
are inserted into the cavities
11
of the housing
10
by passing through the sealing member
30
and the seal holder
40
at the rear of the housing
10
. Immediately before the terminals
20
reach the fully inserted position, the locking lances
12
interfere with the peripheral surface of the mating portions
21
. Therefore, the locking lances
12
flex elastically outward from the housing
10
. When the terminals
20
reach the fully inserted position, the locking lances
12
are elastically restored to the original state and are engaged in the locking holes
24
, thus preventing the terminals
20
from being removed from the cavities
11
. The orientation of the terminals in the upper row of cavities
11
may be reversed relative to that of the terminals in the lower cavity row.
The sealing member
30
is made of rubber, oval-shaped, and thick. As shown in
FIG. 5
, the sealing member
30
is installed on the housing
10
and is sandwiched between the rear end surface of the housing
10
and the front end surface of the seal holder
40
. The construction of the sealing member
30
with the housing
10
and the seal holder
40
is described in more detailed below with reference to
FIGS. 11-13
. A plurality of sealing holes
31
opened through the sealing member
30
is formed coincident with the cavities
11
of the housing
10
. Each sealing hole
31
may be circular, for example. A lip portions
31
A may have a corrugated shape that includes, for example, three convexities. The convexities are circumferentially formed on the inner peripheral surface of each sealing hole
31
. The inner diameter of the lip portion
31
A is smaller than the outer diameter of the coating of the wire
25
. When the wire
25
is in the sealing hole
31
, the lip portion
31
A contacts the peripheral surface of the wire
25
elastically, thus sealing around the wire
25
. Furthermore, as shown in
FIG. 12
, the sealing member
30
includes fit-in holes
32
and
33
through which holding projections
14
and deformation prevention projections
15
pass, respectively.
As shown in
FIG. 11
, the holding projections
14
include a base portion
14
A and a locking portion
14
B. As the base portions
14
A pass through the fit-in holes
32
, the locking portions
14
B enter removal prevention holes
42
and engage with stepped receiving portions
42
A, preventing the housing
10
, the sealing member
30
and the seal holder
40
from being separated. The deformation prevention projections
15
also pass through the fit-in holes
33
and enter deformation prevention holes
43
. The deformation prevention projections
15
prevent deformation of the sealing member
30
.
The inner diameters of the fit-in holes
32
and
33
are smaller than the holding projections
14
and deformation prevention projections
15
, respectively. Thus, when the holding projections
14
and the deformation prevention projections
15
pass the fit in holes
32
and
33
, respectively, the holding projections
14
and the deformation prevention projections
15
contact fit-in holes
32
and
33
with elasticity, sealing around the holding projections
14
and deformation prevention projections
15
.
The peripheral edge of the sealing member
30
is formed as a corrugated sealing edge. A lip portion
34
has, for example, three convexities approximately semi-circular in section and extending circumferentially around the sealing member
30
. The lip portion
34
contacts the inner peripheral surface of the cap
60
elastically, thus sealing between the sealing member
30
and the cap
60
as shown in FIG.
4
.
The seal holder
40
is made of a relatively rigid synthetic resin material. Similarly to the sealing member
30
, the seal holder
40
may be oval-shaped and thick as shown in FIG.
1
. The lip portion
34
formed on the periphery of the sealing member
30
is slightly larger than the periphery of the seal holder
40
. A plurality of terminal insertion openings
41
extend through the seal holder
40
in correspondence to the cavities
11
and the sealing holes
31
. Each terminal
20
is inserted into a respective cavity
11
through a respective terminal insertion opening
41
.
As shown in FIG.
1
and
FIG. 4
, locking projections
44
are formed at each end of upper and lower surfaces of the seal holder
40
. The locking projections
44
engage the cap
60
, thus hindering the cap
60
from being easily removed from the housing
10
, the sealing member
30
, and the seal holder
40
. An index projection
45
is formed in each circular arc-shaped region located at right and left ends of the peripheral surface of the seal holder
40
. Each of the index projections
45
is formed such that the inward side thereof is on a level higher than that of the outward side thereof. The index projections
45
serve as an index for checking the upper and lower sides of the housing
10
when the terminal fixtures
20
are inserted into the cavities
11
and when the housing
10
is inserted into the cap
60
.
As shown in
FIGS. 2
,
4
and
6
each bus bar unit
50
is composed of a holding member
51
made of a relatively rigid synthetic resin material and a metal bus bar
55
that is integrated with the holding member
51
by insert molding. The holding member
51
has a wide sheet-shaped holding portion
52
and a flat cylindrical portion
53
projecting from the sheet-shaped holding portion
52
. The bus bar
55
includes a plurality of connection pieces
57
projecting in parallel with each other, each in the shape of a cantilever, from an edge of a belt-shaped carrier
56
. The bus bar
55
is held with the carrier
56
disposed along the sheet-shaped holding portion
52
and with connection pieces
57
facing the cylindrical portion
53
. Punched holes
54
are formed on the sheet-shaped holding portion
52
in correspondence to the gap between adjacent connection pieces
57
projecting from the carrier
56
. In the process of producing the bus bar units
50
, a portion of the carrier
56
facing each punched hole
54
is punched with a punch and die in correspondence to a predetermined connection pattern. As a result, the carrier
56
is divided (not shown) into a plurality of bus bars
55
. One bus bar
55
has at least three connection pieces
57
. A plurality of terminals
20
are connected by each bus bar
55
through the connection pieces
57
.
Each bus bar unit
50
is installed on the housing
10
in a direction forward therefrom such that the cylindrical portion
53
covers the upper-row cavities
11
or the lower-row cavities
11
. When each bus bar unit
50
has been installed on the housing
10
, the connection pieces
57
are connected with the terminals
20
. Connection patterns can be discriminated from each other by, for example, changing the color of the holding member
51
of the bus bar unit
50
. The upper part of the holding member
51
and the lower part thereof are not symmetrical. Thus, the correct bus bar unit
50
can be installed on the housing
10
in a correct direction, and a group of the terminals
20
can be connected in a correct pattern by checking colors and directions of the holding members
51
.
As shown in
FIG. 2
, guide grooves
58
extend longitudinally and are formed at each of right and left widthwise edges of the cylindrical portion
53
. As shown in
FIG. 1
, front and rear locking projections
17
and
18
correspond positionally to the guide groove
58
and are formed on the housing
10
. Each bus bar unit
50
is brought to a temporary locking position with the locking projections
18
locked in the guide grooves
58
. In this state, the bus bar unit
50
is held at a temporary locking position. In this state, each connection piece
57
is placed at a retracted position at which the connection piece
57
is not in contact with each terminal
20
, thus preventing generation of resistance at the time of insertion of the terminals
20
. The bus bar unit
50
is then brought to the final installation position by locking the front and rear ends of the guide groove
58
by the locking projections
17
and
18
, respectively. In this state, the front and rear ends of the guide groove
58
sandwich the locking projections
17
and
18
.
Each bus bar unit
50
can be used to detect the inserted state of the terminals
20
. As shown in
FIG. 8
, the cylindrical portion
53
is installed on the housing
10
by sliding it along the surface
10
A of the housing
10
. An inclined surface
53
A is formed on the front-end surface of the cylindrical portion
53
such that the outer side thereof extends further than the inner side (housing side) thereof. The inner-side edge of the inclined surface
53
A is a prevention edge
53
B that contacts the excess-flexure prevention surface
12
C of the locking lances
12
. The outer-side edge of the inclined surface
53
A is a balancing edge
53
C which contacts the balancing surface
12
D of the locking lances
12
. When the bus bar unit
50
has been fully inserted to the housing
10
, the front end of the cylindrical portion
53
covers the outer surface of the front portion of the locking lances
12
.
A description of the cap
60
is given with reference to
FIGS. 3 and 7
. The cap
60
is made of a relatively rigid synthetic resin material. As shown in
FIG. 3
, the cap
60
is oval-shaped in a front view and has a closed bottom. Locking holes
61
to which the locking projections
44
of the seal holder
40
, shown in
FIG. 1
, lock are formed at an edge of an opening of the cap
60
. The cap
60
is locked in the installed state by the engagement between the locking projections
44
and the locking holes
61
. Relief portions
62
project outwardly and are formed on the edge of the opening of the cap
60
to prevent the cap
60
from interfering with the index projections
45
of the seal holder
40
. As shown in
FIG. 7
, a region of the inner peripheral surface of the cap
60
near the edge of the opening is formed as a sealing surface
63
with which the lip portion
34
formed on the peripheral edge of the sealing member
30
contacts elastically (see FIG.
4
).
The connector assembly procedure is as follows:
Initially, the sealing member
30
is sandwiched between the seal holder
40
and the housing
10
. Then, the projections
14
formed on the housing
10
are passed through the sealing member
30
, and locking portions
14
B of the projections
14
are locked to the seal holder
40
. This locks the seal member
30
to the housing
10
, and the removal of the seal holder
40
is prevented. Then, terminals
20
are inserted through the terminal insertion openings
41
and the sealing holes
31
into respective cavities
11
. Thereafter, each bus bar unit
50
is installed at a temporary locking position on the housing
10
, and the bus bar unit
50
is placed on an assembling apparatus (not shown). Then, each bus bar unit
50
is pressed to a normal installation portion from the temporary locking position. As a result, the terminals
20
are connected in a predetermined pattern. When the bus bar units
50
are in the normal installing position, the cap
60
is installed on the housing
10
in such a manner that the cap
60
covers the housing
10
and the bus bar unit
50
as shown in FIG.
4
.
The lip portions
34
formed on the periphery of the sealing member
30
prevent water from penetrating into the cap
60
between the inner periphery of the cap
60
and the periphery of the sealing member
30
. Further, the lip portions
31
A of the sealing holes
31
contact the periphery of the wires
25
closely, the inner periphery of each fit-in hole
32
contacts the periphery of the corresponding holding projection
14
, and the inner periphery of the fit-in hole
33
contacts the periphery of the deformation prevention projection
15
. Therefore, water can be prevented from penetrating into the sealing member
30
from outside.
On installation of each bus bar unit
50
on the housing
10
when all the terminals
20
are fully inserted into their respective cavities
11
, each locking lance
12
is undeformed so that its outer surface
12
A is flush with the outer surface
10
A of the housing
10
. Accordingly, when the cylindrical portion
53
slides over the outer surface
10
A of the housing
10
during bus bar unit installation, the cylindrical portion
53
does not interfere with the locking lances
12
. Thus, each bus bar unit
50
can be installed on the housing securely. When each bus bar unit
50
has been installed on the housing
10
in the normal state, the cylindrical portion
53
faces the locking lances
12
in such a manner that the inner surface of the cylindrical portion
53
holds downward on the outer surfaces
12
A of the locking lances
12
. Thus, the locking lances
12
are prevented from being elastically displaced in a direction which would move them away from the terminals
20
(see FIG.
8
).
On the other hand, if there is any terminal
20
inserted into the cavity
11
incompletely, the removal prevention projection
12
B interferes with the outer surface of the mating portion
21
of the terminal
20
. Thus, the locking lance
12
is elastically displaced outward and projects outward from the outer surface
10
A of the housing
10
. During installation of each bus bar unit
50
on the housing
10
, the inclined surface
53
A that is formed at the front end of the cylindrical portion
53
then contacts the outer-side edge of the locking lance
12
. As a result, the installation operator notices that the installation resistance is suddenly increased. In this manner, the operator can detect that a terminal is in the incomplete insertion state (see FIG.
9
).
The operator suspends the installation operation with the connector in the state shown in FIG.
9
and resumes the installation operation after inserting the terminal
20
into the normal position of the cavity
11
. However, it may happen that the operator continues to perform the installing operation without noticing a sudden increase in installation resistance. The locking lance
12
shown in
FIG. 9
is then displaced upward by a force acting in the bus bar unit installation direction, the balancing edge
53
C of the cylindrical portion
53
contacting and transmitting the force to the balancing inclined surface
12
D. If the locking lance
12
were to flex upward further and exceed the limit of its elasticity, it would not be restorable to the undeformed state shown in FIG.
8
. However, this is prevented because when the locking lance
12
flexes further, to a position still within its elastic limit, the prevention edge
53
B of the cylindrical portion
53
contacts the excess-flexure prevention surface
12
C (see FIG.
10
). The excess-flexure prevention surface
12
C has an inclination such that the locking lance
12
is urged in the opposite (elasticity-restoring) direction by the collision force of the cylindrical portion
53
applied to the excess-flexure prevention surface
12
C. Thus, the locking lance
12
is prevented from being elastically displaced further.
As described above, as a mechanism to prevent the locking lances
12
from flexing excessively beyond the limit of their elasticity, the cylindrical portion
53
is pressed against the excess-flexure prevention surface
12
C. Thus, it is also unnecessary to provide the housing
10
with a wall for preventing excess deformation of the locking lance
12
, which makes it possible to reduce the width of the housing
10
.
When the cylindrical portion
53
of each bus bar unit
50
contacts both the excess-flexure prevention surface
12
C and the balancing surface
12
D, as shown in
FIG. 10
, the locking lances
12
are prevented from being displaced in either direction. Thus installation of the bus bar unit
50
on the housing
10
is prevented. That is, even if the bus bar unit
50
is pressed strongly against the lances
12
, the lances
12
are prevented from being forcibly displaced in the elasticity-restoring direction. In particular, when the cylindrical portion
53
contacts the balancing surfaces
12
D, the locking lances
12
are spaced from the terminals
20
. Therefore, even though the locking lance
12
may be displaced slightly in the elasticity-restoring direction, there is no possibility that the locking lance
12
is urged excessively against the terminals
20
.
The acute angle α formed between the insertion direction of the cylindrical portion
53
and the excess-flexure prevention surface
12
C is smaller than the angle β which formed between the insertion direction and the balancing surface
12
D. Thus, when a force acting in the installation direction is initially applied to the locking lances
12
by the cylindrical portion
53
, the resultant force that is applied to the locking lances
12
in the downward (elasticity-restoring) direction (i.e., torward the cavity) is greater than the resultant force that is applied in the upward (increased elastic displacement) direction (i.e., away from the cavity). Accordingly, it is possible to prevent excess deformation of the locking lances
12
.
The inclined surface
53
A of the cylindrical portion
53
may be inclined with respect to the bus bar unit-installation direction, as shown in the drawings. Therefore, even if the locking lances
12
may be slightly raised with respect to the outer surface
10
A of the housing
10
when the terminals
20
are fully inserted, the lances
12
are not snagged by prevention edge
53
B of the cylindrical portion
53
during installation of each bus bar unit
50
into the housing
10
.
The present invention is not limited to the embodiments described, but may be varied, for example, as described below.
(1) In the above description, the front end surface of the cylindrical portion
53
of the bus bar unit
50
is angled and the edges of the surface contact the excess-flexure prevention surface
12
C and the balancing surface
12
D. However, within the present invention, the front end surface of the cylindrical portion
53
may be V-shaped so that the end surface corresponds to and contacts the excess-flexure prevention surface
12
C and the balancing surface
12
D.
(2) In the above description, the acute angle α between the insertion direction of the cylindrical portion
53
and the excess-flexure prevention inclined surface
12
C is smaller than the angle β between the insertion direction and the balancing inclined surface
12
D. However, within the present invention, although less desirably, angle α may be larger than angle β or angle α may be equal to angle β.
(3) In the above description, the balancing surface
12
D is in addition to the excess-flexure prevention surface. However, within the present invention, it is possible to form only the excess-flexure prevention inclined surface.
(4) In the above description, the end surface of the cylindrical portion
53
is angled relative to the insertion direction of the cylindrical portion. However, according to the present invention, the end surface of the cylindrical portion
53
may be perpendicular to the insertion direction, or may be angled in the opposite direction.
(5) In the above description, the cylindrical portion
53
initially contacts the outer-side edge of the locking lance
12
when a terminal is partially inserted. However, within the present invention, the cylindrical portion
53
may contact an inclined surface of the locking lance
12
initially. In this case, the locking lance
12
first contacts the balancing surface
12
C, and thereafter the excess-flexure prevention surface
12
D after slight displacement of the locking lance
12
. Alternatively the cylindrical portion
53
may contact both inclined surfaces.
(6) In the above description, a connector of waterproof type has been described. However, the present invention is also applicable to connectors of non waterproof type.
Although the invention has been described above in relation to particular embodiments, many variations are possible within the spirit and scope of the invention herein described, as will be appreciated by those who are skilled in the art, once given this disclosure.
Claims
- 1. A connector comprising:a housing having an outer peripheral surface, a plurality of cavities, a plurality of resiliently deformable locking members, and a plurality of terminals, each of said terminals being inserted in a respective one of said cavities and having (a) a partially inserted position in which said terminal bears on said locking member to deform said locking member so that said locking member is deflected outward of said outer peripheral surface, and (b) a fully inserted position in which said locking member snap-fits to said terminal thereby locking said terminal in said cavity; and a bus bar holder having a sleeve and a plurality of bus bar tab pieces said bus bar tab pieces being accommodated in said sleeve, and said sleeve being push-fitted onto said peripheral surface of said housing to install said bus bar holder to said housing and to contact said tab pieces to said terminals, whereby said terminals are electrically connected to each other; wherein each locking member has a first end surface portion which is inclined with respect to a push-fit direction of said sleeve, whereby when one or more of said terminals are in said partially inserted position with one or more respective said locking members deflected outward of said outer peripheral surface when push-fitting said sleeve onto said housing, said sleeve bears on said end surface portion to urge the one or more said locking members toward said terminal thereby preventing excess deformation of the one or more said locking members.
- 2. The connector according to claim 1, wherein each said locking member has a second end surface portion which faces said first end surface portion and, with respect to said first end surface portion, is oppositely inclined with respect to the push-fit direction of said sleeve, whereby when, on push-fitting of said sleeve onto said housing, each of said terminal is in said partially inserted position with the respective said locking member deflected outward of said outer peripheral surface, said sleeve bears on said second surface portion to urge said locking member away from said terminal.
- 3. The connector according to claim 2, wherein said first and second end surface portions define a V-shaped recess in said locking member.
- 4. The connector according to claim 2, wherein said first and second end surface portions are formed so that when, on push-fitting of said sleeve onto said housing, said terminal is in said partially inserted position with each of said locking member deflected outward of said outer peripheral surface, said sleeve bears on both said first and said second end surface portions.
- 5. The connector according to claim 4, wherein said first and said second end surface portions are formed so that when said sleeve bears on both said first and said second end surface portions, an angle of inclination of said first end surface portion with respect to said push-fit direction is smaller than the angle of inclination of said second end surface portion with respect to said push-fit direction.
Priority Claims (3)
Number |
Date |
Country |
Kind |
11-105919 |
Apr 1999 |
JP |
|
11-105920 |
Apr 1999 |
JP |
|
11-118479 |
Apr 1999 |
JP |
|
US Referenced Citations (11)
Foreign Referenced Citations (3)
Number |
Date |
Country |
U-2-61082 |
May 1990 |
JP |
U-4-42082 |
Apr 1992 |
JP |
A-9-213436 |
Aug 1997 |
JP |