BACKGROUND OF THE INVENTION
[0001] The present invention relates to a lock detecting connector which can detect that
a pair of connectors engageable with each other are in a complete locked state.
[0002] Recently, automobiles carry air bags. Safety devices such as these air bags must
be highly reliable, which thus demands that incomplete connection of male and female
connectors be avoided with certainty. To meet such demand, connectors whose complete
connection is detected electrically have been developed to date.
[0003] Fig. 1 shows a conventionally known lock detecting structure of this type. A groove-like
engagement portion 1a is formed on the upper surface of a connector 1 on the male
side that is firmly fixed on a board 2. On the other hand, a flexible lock piece having
a projection 7a is integrally formed on the upper surface of a connector 5 on the
female side to be engaged with the connector 1 on the male side, the projection 7a
being held by the engagement portion 1a when both connectors 1, 5 are connected.
[0004] In addition, within the connector 1 on the male side, a pair of lock detecting electrodes
4a, 4b are disposed while positioned on both sides of an inverted T-shaped position
determining piece 3 as shown in Fig. 2. On the other hand, within the connector 5
on the female side, a U-shaped short circuit electrode 6 is arranged so as to interpose
the position determining piece 3 between the leg portions thereof as shown in Fig.
2.
[0005] In the thus designed lock detecting structure, as the connector 5 on the female side
is being inserted into the connector 1 on the male side while elastically deforming
a flexible lock piece 7 thereof, the short circuit electrode 6 is elastically deformed
upward by a guide projection 3b formed on a partition wall 3a of the position determining
piece 3 as shown in Fig. 3, so that the short circuit electrode 6 keeps distance from
the detecting electrodes 4a, 4b at the initial stage of the insertion. Then, when
the connector 5 on the female side has been inserted into a regular position of the
connector 1 on the male side, the projection 7a of the flexible lock piece 7 is held
by the engagement portion 1a to thereby unremovably lock both connectors 1, 5. At
the same time, the short circuit electrode 6 comes out of the projection 3b to come
in contact wish the lock detecting electrodes 4a, 4b as shown in Fig. 4. The lock
detecting electrodes 4a, 4b are connected to a not shown detecting circuit, so that
it is judged that both connectors 1, 5 have been connected in the locked state by
way of short-circuiting the lock detecting electrodes 4a, 4b.
[0006] In the aforementioned conventional lock detecting structure, the short circuit electrode
6 is disposed within the connector 5 on the female side. This structure is advantageous
in preventing the detecting electrodes 4a, 4b from being short-circuited while insulated
by foreign matter such as dirt and dust upon contact between the detecting electrodes
4a, 4b and the short circuit electrode 6, since foreign matter is hard to deposit
on the short circuit electrode 6. However, this structure does not allow the user
to check the condition of the short circuit electrode 6 visibly; i.e., the short circuit
electrode 6 is left concealed, and this is undesirable in terms of quality control.
[0007] To overcome this problem, the short circuit electrode may be disposed on the outer
surface of the connector, and a cover may be provided to cover the entire part of
the connector having the short circuit electrode as long as the connector having the
short circuit electrode is not connected to the mating connector. And the cover may
be removed to expose the short circuit electrode when the short circuit electrode
must be inspected visibly or when the connector having the short circuit electrode
is connected to the mating connector. However, this design is still disadvantageous
in involving an extra step of removing the cover prior to connecting both connectors,
which leads to a reduction in the efficiency of the entire connecting operation.
[0008] An example of the connector using the above lock detection structure is shown in
Figs. 5 and 6.
[0009] Fig. 5 shows a connector housing 40 on the male side. A plurality of male terminals
41 are accommodated within the housing 40, and these terminals 41 project outward
through the wall surface in the back of the housing 40. In addition, from the wall
surface in the back projects a rib 42, which extends in parallel with the terminals
41 within the housing 40. A partition wall 43 standing upright in the middle of the
rib 42 divides the upper surface of the rib 42 into right and left parts. Lock detecting
terminals 44 are disposed on such right and left parts of the rib 42. Both lock detecting
terminals 44 project outward through the wall surface in the back of the housing 40
like other terminals. On the other hand, a connector housing 45 on the female side
accommodates a not particularly shown short circuit terminal. The short circuit terminal
has such a shape as to come in contact with the lock detecting terminals 44 simultaneously
upon engagement (complete engagement) of the connector housings 40, 45. Therefore,
when both connector housings 40, 45 have been engaged with each other completely,
both lock detecting terminals 44 are ready to conduct through the short circuit terminal.
As a result, the complete engagement can be detected electrically.
[0010] However, the aforementioned structure in which the lock detecting terminals are disposed
in the middle of the connector housing 40 addresses a problem shown in Fig. 7. The
problem is that the edge portion of the connector housing 45 on the female side is
caught on the distal end of the rib 43 or on the distal ends of the lock detecting
terminals 44 when both housings 40, 45 are being engaged misaligned. This causes the
rib and the like to be deformed, which may in turn make engagement of the connector
housings or lock detection of the connector housings impossible depending on the degree
of deformation.
SUMMARY OF THE INVENTION
[0011] The present invention has been made in consideration of the aforementioned circumstances
and its object resides in providing a connector whose lock detecting terminals are
not deformed even when the connectors are being engaged with each other misaligned.
[0012] Another object resides in providing a lock detecting structure for connectors which
facilitates quality control and prevents reduction in the efficiency of the operation
of connecting the connectors.
[0013] To accomplish the above object, the present invention is applied to a lock detecting
connector, which includes at least a pair of lock detecting terminals in one of connector
housings and a short circuit terminal in the other connector housing, the short circuit
terminal serving to detect a locked state of both connector housings by way of short-circuiting
the pair of lock detecting terminals with both connector housings engaged with each
other completely, wherein the lock detecting connector is characterized in that the
lock detecting terminals are arranged along an inner wall surface of the one connector
housing accommodating the lock detecting terminals, and that distal ends of the lock
detecting terminals are positioned backward with respect to an engagement opening
of the one connector housing.
[0014] Furthermore, to accomplish the above object, the present invention is applied to
a connector, which includes at least a pair of lock detecting terminals in one of
connector housings and a contact terminal in the other connector housing, the contact
terminal serving to detect a locked state of both connector housings by way of short-circuiting
the pair of lock detecting terminals with both connector housings engaged with each
other completely, wherein the connector is characterized in that the lock detecting
terminals are arranged along an inner wall surface of the one connector housing accommodating
the lock detecting terminals, and that protective walls for covering the lock detecting
terminals are formed on an inner surface of the one connector housing excluding a
portion of the inner surface coming in contact with the contact terminal.
[0015] According to the aforementioned construction, even when one connector housing is
misaligned with the mating connector housing at the time of engaging both connector
housings, it is prevented that the edge portion of the housing on the short circuit
side will come in contact with the lock detecting terminals.
[0016] The advantageous effects of the present invention are as follows. Since the lock
detecting terminals are disposed along the inner wall surface of the connector housing
accommodating the lock detecting terminals as well as backward with respect to the
engagement opening thereof, the case where the lock detecting terminals are deformed
by forcible engagement can be obviated even if both connector housings are being engaged
misaligned.
[0017] Furthermore, to accomplish the above object, the present invention is applied to
a lock detecting structure for connectors wherein a short circuit electrode is disposed
on one of a pair of connectors being connected so as to be unremovable by engagement
of a flexible lock piece with an engagement portion, and detecting electrodes are
disposed on the other connector, the detecting electrodes coming in contact with the
short circuit electrode when both connectors have been locked, so that locking of
both connectors can be detected by contact between the short circuit electrode and
the detecting electrodes, wherein the lock detecting structure is characterized in
that the one connector has the short circuit electrode exposed to the outside and
has a cover movable between a protecting position and an opening position, the protecting
position being such a position as to allow the cover to cover the short circuit electrode,
and the opening position being such a position as to allow the cover to expose the
short circuit electrode, and that the cover is pushingly moved from the protecting
position to the opening position by the other connector as both connectors are being
connected.
[0018] With both connectors not connected to each other, the cover disposed on one of the
connectors is set to the protecting position at which the short circuit electrode
is covered. Foreign matter such as dirt and dust is hard to deposit on the short circuit
electrode under this condition. When the cover is moved from the protecting position
to the opening position, whether foreign matter is deposited on the short circuit
electrode can be visibly checked.
[0019] In addition, the operation of connecting both connectors is carried out when the
cover on the one connector is set to the protecting position. As both connectors are
being connected each other, the cover is moved from the protecting position to the
opening position while pushed by the other connector, so that the short circuit electrode
is ready to come in contact with the detecting electrodes. When both connectors have
been correctly connected and locked so as not to be removable, the detecting electrodes
come in contact with the uncovered short circuit electrode, which allows the locked
state of both connectors to be detected.
[0020] As described in the mode of operation, the present device is characterized as allowing
the user to visibly check the condition of the short circuit electrode, which facilitates
quality control. The present device is also characterized as dispensing with the extra
step of removing the cover prior to the operation of connecting both connectors, which
contributes to improved efficiency in the connecting operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021]
Fig. 1 is a perspective view of the appearance of a conventional lock detecting structure;
Fig. 2 is a perspective view of a short circuit electrode and lock detecting electrodes;
Fig. 3 is a side view showing connection between the short circuit electrode and the
lock detecting electrodes;
Fig. 4 is a side view showing connection between the short circuit electrode and the
lock detecting electrodes;
Fig. 5 is a front view of a conventional housing on the male side;
Fig. 6 is a side sectional view of Fig. 5;
Fig. 7 is a sectional view showing a conventional problem;
Fig. 8 is a perspective view of a lock connector, which is a first embodiment of the
present invention;
Fig. 9 is a perspective view of a short circuit terminal and lock detecting terminals;
Fig. 10 is a sectional view of the lock connector for showing a procedure for an electrical
connection;
Fig. 11 is a sectional view of the lock connector for showing a procedure for electrical
connection;
Fig. 12 is a sectional view of the lock connector for showing a procedure for electrical
connection;
Fig. 13 is a front view of a male housing of the second embodiment;
Fig. 14 is a side sectional view of Fig. 13;
Fig. 15 is a perspective view of the male housing as viewed from below with lock detecting
terminals cut away therefrom;
Fig. 16 is a sectional view of the connector housings in the course of being engaged;
Fig. 17 is a sectional view of the connector housings having been completely engaged;
Fig. 18 is a plan view of a female housing;
Fig. 19 is a perspective view of the appearance of a connector on the female side
with a cover removed therefrom;
Fig. 20 is a perspective view of the appearance of the connector on the female side
with the cover attached thereto;
Fig. 21 is a sectional view of a connector on the male side and the connector on the
female side disconnected from each other;
Fig. 22 is a sectional view of the connector on the male side and the connector on
the female side connected to each other;
Fig. 23 is a partially cutaway plan view of the connector on the female side with
the cover removed therefrom;
Fig. 24 is a partially cutaway plan view of the connector on the female side with
the cover set to a protecting position;
Fig. 25 is a partially cutaway plan view of the connector on the female side with
the cover set to a detecting position;
Fig. 26 is a partially enlarged sectional view of the connector on the male side and
the connector on the female side when connection of both connectors is started;
Fig. 27 is a partially enlarged sectional view of the connector on the male side and
the connector on the female side when the connection of both connectors is being effected;
and
Fig. 28 is a partially enlarged sectional view of the connector on the male side and
the connector on the female side when the connection of both connectors has been completed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] An embodiment of the present invention will now be described hereinafter with reference
to the drawings.
First Embodiment:
[0023] Fig. 8 is a perspective view of a lock connector, which is a first embodiment of
the present invention.
[0024] Referring to the drawing, a connector housing 110 on the male side includes a plurality
of small chambers 111 each formed therethrough in the axial direction of cables, and
each of the small chambers 111 serves to hold a terminal on the female side inserted
thereinto not only in the provisionally engaged state but also in the normally engaged
state with the aid of a retainer 120. In addition, an axially extending groove-like
recess 112 is formed at the intermediate part of the upper surface of the connector
housing 110 on the female side, and a flexible lock piece 113 is formed in the recess
112 while extending from the rear side toward the front side in the slantwise upward
direction. A pinching portion 113a is formed at the foremost end part of the flexible
lock piece 113, and moreover, an axially extending elongated engagement hole 113b
is formed through the flexible lock piece 113 at the position located slightly behind
the pinching portion 113a.
[0025] The flexible lock piece 113 is provided with a short circuit terminal 114 as shown
in Fig. 9. The short circuit terminal 114 is composed of electrode portions 114a for
holding a part of the flexible lock piece 113 between the engagement hole 113b and
the pinching portion 113a so as to clamp such part of the flexible lock piece 113
and a spring portion 114b having a U-shaped sectional contour and integrated with
the electrode portions 114a, and the lowermost end of the spring portion 114b comes
in contact with the bottom surface of the recess 112. It should be noted that a pair
of contact protuberances 114a₁ are formed on the upper surface of the electrode portions
114a.
[0026] On the other hand, a connector housing 130 on the male side is designed in the hood-shaped
configuration in such a manner as to enable the connector housing 110 on the female
side to be inserted into the housing 130 on the male side, and a plurality of terminals
on the male side each adapted to be electrically connected to a terminal on the female
side are supported in the connector housing 130 on the male side at the positions
located opposite to the small chambers 111 in the connector housing 110 on the female
side. In addition, a pair of axially extending position determining ribs 131a and
131b adapted to come in contact with the opposite side surfaces of the recess 112
for the purpose of position determination are formed on a ceiling surface of the connector
housing 130 on the male side. Additionally, an engagement rib 132 adapted to be brought
in engagement with the engagement hole 113b when the connector housing 110 on the
female side 110 is inserted into the connector housing 130 on the male side to reach
a normal position is formed on the ceiling surface of the connector housing 130 on
the male side at the intermediate position between both the position determining ribs
131a and 131b. A pair of lock detecting terminals 133a and 133b as shown in Fig. 9
are disposed on a ceiling surface 130a with the rib 132 located at the intermediate
position between both the position determination ribs 131a and 131b. The pair of lock
detecting terminals 133a and 133b are disposed so as to extend along such ceiling
surface 130a in intimate contact therewith, and the contact surfaces of the lock detecting
terminals are kept open to the outside while facing downward. In addition, while the
position of the distal ends of both lock detecting terminals 133a, 133b is substantially
aligned with the opening edge of the connector housing 130 on the male side in this
embodiment, an opening edge portion at which both lock detecting terminals 133a, 133b
are disposed is recessed backward with respect to the remaining opening edge portion.
Therefore, it can be said that the distal ends of both lock detecting terminals 133a,
133b are positioned backward with respect to the engagement opening, taking into account
the fact that the actual engagement opening with the connector housing 110 on the
female side is formed by a surface including the remaining opening edge portion of
the connector housing 130 on the male side. In other words, the distal ends of both
lock detecting terminals 133a, 133b are set to such a position as not to come in contact
with the front edge of the connector housing 110 on the female side even if an attempt
is made to engage the connector housing 110 on the female side obliquely with the
connector housing 130 on the male side.
[0027] The connector housing 130 on the male side includes a fixing portion 134 on the lower
surface thereof which is fixedly secured to a not shown printed circuit base board,
and the terminals on the male side held in the connector housing 130 on the male side
and the lock detecting terminals 133a and 133b are electrically connected to the printed
circuit base board.
[0028] Next, a mode of operation of the lock connector constructed in the aforementioned
manner will be described below.
[0029] With respect to the connector housing 110 on the female side, a plurality of terminals
on the female side each having a cable connected thereto by crimping are firmly held
in the chambers 111 with the aid of the retainer 120, and the short-circuit electrode
114 is disposed on the flexible lock piece 113. At this time, the upper surface of
the spring portion 114b of the short circuit terminal 114 comes in contact with the
lower surface of the flexible lock piece 113, while the lower surface of the same
comes in contact with the upper surface of the recess 112, causing the flexible lock
piece 113 to be normally biased in the upward direction. On the other hand, the connector
housing 130 on the male side is fixedly mounted on the printed circuit base board
via the fixing portion 134.
[0030] As shown in Fig. 10, the connector housing 110 on the female housing is located opposite
to the connector housing 130 on the male side, arid subsequently, the former is inserted
into the latter in such a manner that the position determining ribs 131a and 131b
on the latter are received in the recess 112 of the former.
[0031] Since the engagement rib 132 is increasingly brought in contact with the upper surface
of the flexible lock piece 113 as the connector housing 110 on the female side is
inserted into the connector housing 130 on the male side as shown in Fig. 11, the
flexible lock piece 113 is curvedly bent in the downward direction. At this time,
the electrode portions 114a of the short circuit terminal 114 are displaced in the
downward direction, but they are not brought in contact with both the terminals 133a
and 133b even when they reach the position where the lock detecting terminals 133a
and 133b are superimposed on the electrode portions 114a.
[0032] However, when the connector housing 110 on the female side is inserted into the connector
housing 130 on the male side to reach a normal position, the engagement rib 132 faces
the engagement hole 113b, and thereafter, it is received in the latter, causing the
flexible lock piece 113 to be upwardly pushed back by the action of resiliency of
the flexible lock piece 113 itself as well as by the action of resiliency of the spring
portion 114b of the short circuit terminal 114. In such manner, the connector housing
110 on the female side is engaged with the connector housing 130 on the female side
in cooperation of the engagement rib 132 with the engagement hole 113b.
[0033] On the other hand, the electrode portions 114a of the short circuit terminal 114
are formed in such a manner that a part of the flexible lock piece 113 is seized by
the electrode portion 114a of the short circuit terminal 114 in the clamped state.
In addition, since the lock detecting terminals 133a and 133b are arranged on the
opposite sides of the engagement rib 132, when the flexible lock piece 113 is upwardly
pushed back in that way, the electrode portions 114a of the short circuit terminal
114 is electrically connected to both the lock detecting terminals 133a and 133b by
way of short-circuiting. Specifically, the former are short-circuited to the latter
in the same timing relationship as that when the connector housing 110 on the female
side is engaged with the connector housing 130 on the male side. Since the lock detecting
terminals 133a and 133b are arranged in the connector housing 130 on the female side
which is fixedly secured to the printed circuit base board, they are reliably held
in the connector housing 130 on the male side regardless of any intensity of vibration
imparted thereto, whereby the locked state between both the connector housings 110
and 130 can be detected with excellent reliability.
[0034] In such manner, the connector housing 110 on the female side includes the short circuit
terminal 114 on the surface onto which the flexible lock piece 113 is biased, and
the connector housing 130 on the male side holds the pair of lock detecting terminals
133a and 133b at the position where the pair of lock detecting terminals 133a and
133b come in contact with the flexible lock piece 113 when the flexible lock piece
113 is elastically restored after engaged with the connector housing 130 by flexing.
Thus, the elastic restoring action of the flexible lock piece 113 and the short-circuiting
between two opponent terminals are simultaneously achieved without any deviation from
the correct timing relationship established among these components.
[0035] By the way, this embodiment is characterized as arranging the lock detecting terminals
133a, 133b so as to extend along the ceiling surface 130a and positioning the distal
ends thereof backward with respect to the engagement opening of the housing 130 so
that front edge of the connector housing 110 on the female side cannot reach the lock
detecting terminals even when the connector housing 110 on the female side is being
engaged with the connector housing 130 on the male side misaligned. Therefore, there
is no likelihood that the connector housing 110 on the female side will be caught
on the lock detecting terminals 133a, 133b. Hence, the lock detecting terminals 133a,
133b can be held at a normal position at all times, which not only facilitates connector
housing engagement operation but also contributes to reliable lock detection.
[0036] It should be noted that the present invention may be modified in various modes. While
the lock detecting terminals 133a and 133b are disposed on the ceiling surface of
the housing, these terminals may be disposed, e.g., on a side wall surface of the
housing. In addition, while a curvedly bent opening edge of the housing 130 such that
an portion thereof at which the lock detecting terminals are disposed is recessed
backward has been described, that portion may not necessarily be recessed backward
as such, but may be flush with the remaining portion.
Second Embodiment
[0037] Figs. 13 to 15 show a connector housing on the male side (hereinafter referred to
as "male housing 201") of a connector constructed according to the second embodiment.
The male housing is of a square cylinder that is open on one side. Inside the male
housing is an engagement chamber 203 that allows a connector housing on the female
side (hereinafter referred to as "female housing 202") to be inserted thereinto. In
addition, a plurality of insertion holes 204 for inserting male terminals 205 are
formed on the rear wall surface of the engagement chamber 203 so as to pass therethrough.
Male terminal 205 portions projecting outside the housing 201 are bent downward so
as to be substantially perpendicular, and the ends thereof are inserted into corresponding
positions on a PCB board (not shown) in this embodiment. Further, to prevent these
ends of the terminals from being out of position, a correcting plate 206 is provided
in this embodiment. As shown in Fig. 14, the correcting plate 206 projects from the
bottom of the male housing 201. The correcting plate 206 has a plurality of small
through holes 207 corresponding to the terminals so that the terminals 205 can be
held while inserted into such small through holes 207. Furthermore, a guide projection
208 for guiding the female housing 202 engaging operation is projected from the middle
part of the rear wall surface in the engagement chamber 203. This guide projection
208 extends horizontally and longer than the terminals in the frontward direction.
Still further, a retaining projection 209 for locking the female housing 202 is formed
at a position that is in the middle of the upper wall surface of the engagement chamber
203 and closer to the opening edge of the front surface of the engagement chamber
203 (see Fig. 15). The retaining projection 209 will be described later.
[0038] It should be noted that reference numeral 210 denotes a recess for reducing frictional
resistance at the time of engagement. A pair of recesses 210 are formed on the confronting
side wall surfaces of the engagement chamber 203.
[0039] On the other hand, the female housing 202 that is engageable with the engagement
chamber 203 has a plurality of terminal accommodating chambers 211 such as shown in
Figs. 16, 17 so as to correspond to the aforementioned male terminals 205. Female
terminals (not shown) connectable to the male terminals 205 are accommodated in the
terminal accommodating chambers 211 so as not to come off. In addition, window portions
212 pass through the female housing 202 horizontally so as to be surrounded by the
terminal accommodating chambers 211. These window portions 212 receive the aforementioned
guide projection 208 when both housings 201, 202 are engaged with each other.
[0040] Furthermore, a resilient operation piece 213 for locking the male housing 201 is
disposed in the middle of the upper surface of the female housing 202 (see Figs. 16
to 18). This resilient operation piece 213 is formed so as to be cantilevered with
the edge portion on the engagement surface side of the male housing 201 as a fulcrum,
so that the resilient operation piece 213 can be flexed up and down. In addition,
an operation portion 213a is formed on the free end side of the resilient operation
piece 213. A portion between the operation portion 213a and the fulcrum is frame-like
and has a short circuit terminal 214 made of an electrically conducting material and
is formed in the following manner. One end side of the short circuit terminal 214
is inserted into an insertion hole 215 formed horizontally at the fulcrum of the resilient
operation piece 213, and is designed so as not to come off while hooked by a pawl
216 formed by cutting a part of the hole 215 out. Still further, the other end side
of the short circuit terminal 214 is inserted into a slit 217 formed at the operation
portion 213a. Still further, an engagement hole 218 is opened at the position close
to the operation portion 213a of the short circuit terminal 214. The engagement hole
218 is engaged with the retaining projection 208 when both housings 201, 202 are engaged
with each other. Still further, a pair of protuberances 219 are arranged so as to
interpose the engagement hole 218 therebetween. These protuberances 219 serve to short-circuit
the terminals by coming in contact with both lock detecting terminals 220, which will
be described later, when both housings 201, 202 are engaged with each other.
[0041] Both lock detecting terminals 220 are made of pin-like electrically conducting metal
pieces that are bent so as to be substantially perpendicular at an intermediate position
like the male terminals 205. One end side of each lock detecting terminal 220 is disposed
within the engagement chamber 203 through an insertion hole 221 for detecting the
male housing 201, while the other end side thereof is disposed at a predetermined
position through the small hole 207 of the correcting plate 206. The ends of the lock
detecting terminals 220 which are inserted into the engagement chamber 203 extend
along the upper wall surface of the engagement chamber 203 up to positions right at
the front opening edge of the engagement chamber 3 while keeping a predetermined distance
from each other. In addition, the distal ends of there lock detecting terminals 220
are bent perpendicularly in such a direction as to meet each other, so that the distal
ends confront each other while interposing the aforementioned retaining projection
209 therebetween. The bent portions serve as contact portions 222 that come in contact
with the short circuit terminal 214.
[0042] Furthermore, protective walls 223 are formed integrally on the upper wall surface
of the engagement chamber 203, the protective wall 223 serving to cover both lock
detecting terminals 220, respectively. Both protective walls 223 are formed so that
the front edges thereof are flush with the front edge of the engagement chamber 203,
and extend almost all along the length of the upper wall surface. In addition, the
section of each protective wall facing the opening side is substantially L-shaped.
Specifically, both lock detecting terminals 220 are inserted into the engagement chamber
203 from the detecting terminal insertion hole 221, introduced into terminal holding
grooves 224 within the protective walls 223 thereafter, and held while interposed
within the terminal holding grooves 224 almost without gap. However, the portions
of both protective walls 223 facing the front edge portion of the engagement chamber
203 are cut away so that the contact portions 222 of both lock detecting terminals
220 are exposed.
[0043] Next, advantageous effects of the thus constructed embodiment will be described specifically
(see Figs. 16, 17). When the female housing 202 is pushed into the male housing 201
while aligned with the male housing 201 to engage the female housing 202 with the
male housing 201, the retaining projection 209 presses the upper surface of the short
circuit terminal 214 down, which in turn flexes the resilient operation piece 213
downward. Upon complete engagement of both housings 201, 202, the retaining projection
209 is adapted to the engagement hole 218, so that the resilient operation piece 213
returns upward. As a result, the retaining projection 209 is engaged with the engagement
hole 218, which in turn causes both housings 201, 202 to be engaged with each other
so as not to come off from each other. Simultaneously therewith, since both protuberances
219 of the short circuit terminal 214 come in contact with the contact portions 222
of both lock detecting terminals 220, both lock detecting terminals 220 are short-circuited.
Therefore, if both lock detecting terminals are conducting, then complete engagement
of both housings 201, 202 is detected electrically through both lock detecting terminals
that are conducting.
[0044] By the way, even if both housings 201, 202 are misaligned at the time of engagement,
there is no likelihood that the edge portion of the female housing 202 will be caught
on the contact portions 222 of the lock detecting terminals 220, since the protective
walls 223 cover the detecting terminals 220 and the front edge surfaces of the protective
walls 223 are designed to be substantially flush with the opening edge of the housing
201. Therefore, deformation of the lock detecting terminals 220 can be obviated, which
not only allows the lock detecting terminals 20 to be held in regular position at
all times, but also facilitates housing 201, 202 engaging operation and contributes
to reliable lock detection.
[0045] It should be noted that the present invention may be modified in various modes. For
example, the lock detecting terminals 220 may be disposed on the side wall surfaces
of the housing, although the lock detecting terminals 220 are disposed on the upper
wall surface of the housing in this embodiment.
Third Embodiment
[0046] A third embodiment of the present device will now be described in detail hereinafter
with reference to Figs. 19 to 28.
[0047] Fig. 19 shows a connector 310 on the female side having cavities 311 into which not
shown female terminal fittings are inserted. The connector 310 on the female side
is made of synthetic resin. An axially extending flexible lock piece 312 is formed
integrally on the upper surface of the connector 310 so as to be elastically deformable
vertically. This flexible lock piece 312 is formed by coupling a pair of slenderly
extending arm portions 313, 313 to a block portion 314. Guide projections 315 for
guiding a cover 320 are formed on the outer surfaces of both arm portions 313, 313.
The cover 320 will be described later.
[0048] In addition, a short circuit electrode 316 is interposed between both arm portions
313, 313 so as to be elastically deformable integrally with the arm portions. The
short circuit electrode 316 is made of a metallic plate. An engagement hole 317 is
formed at a position that is rather rearward with respect to the middle of the short
circuit electrode 316 in the axial direction. On the upper surface of the short circuit
electrode 316 are a pair of contacts 316a, 316a. These contacts 316a, 316a are positioned
on both sides of the engagement hole 317.
[0049] Moreover, the cover 320 for protecting these contacts 316a, 316a of the short circuit
electrode 316 is attached to the flexible lock piece 312. The cover 320 is composed
of a protective plate portion 321 and a pair of slide portions 322, 322. The protective
plate portion 321 spans the arm portions 313, 313 of the flexible lock piece 312 and
the short circuit electrode 316, and the slide portions 322, 322 are formed at both
ends of the protective plate portion 321 and extend in parallel with the arm portions
313, 313. The cover 320 not only allows guide grooves 323 formed on the inner surfaces
of the slide portions 322 to be fitted with the guide projections 315 by causing the
slide portions 322 to move along the outer surfaces of the arm portions 313, but also
allows the rear ends of the slide portions 322 to be fitted with guide recessed 318
formed on the sides of the block portion 314, so that the cover 320 can move relative
to the connector 310 on the female side in the axial direction. When the cover 320
is set to a protecting position that is at the front end of the movable range thereof,
the protective plate portion 321 covers the contacts 316a, 316a from above, whereas
when the cover 320 is set to an opening position that is at the rear end of the movable
range thereof, the protective plate portion 321 exposes the contacts 316a, 316a while
displaced rearward from the contacts 316a, 316a.
[0050] On the other hand, located on the left side in Fig. 21 is a connector 330 on the
male side made of synthetic resin. The connector 330 on the male side has male terminal
fittings 332 that project toward a hood portion 331 in the front and confront the
cavities 311 of the connector 310 on the female side. A pair of L-shaped detecting
electrodes 333, 333 connected to a not shown detecting circuit are attached to the
connector 330 on the male side so as to extend along and project from the upper inner
wall of a hood portion 331 of the connector 330. Both detecting electrodes 333, 333
are such that distal ends thereof 333a, 333a projecting toward the hood portion 331
are inwardly bent, and such inwardly bent portions 333a, 333a are coupled to each
other by an insulating engagement portion 335 (equivalent to the engagement portion
recited in the claim of the present device) that projects downward from the bent portions
333a, 333a. With the connector 310 on the female side being correctly inserted into
the hood portion 331 of the connector 330 on the male side, not only the distal ends
333a, 333a of the detecting electrodes 333, 333 come in contact with the contacts
316a, 316a of the short circuit 316 from above, but also the engagement portion 335
is fitted into the engagement hole 317 of the short circuit electrode 316 from above.
[0051] Next, a mode of operation of this embodiment will be described.
[0052] With the connector 310 on the female side not connected to the connector 330 on the
male side, the cover 320 of the connector 310 on the female side is set to the protecting
position at which the contacts 316a, 316a of the short circuit electrode 316 are covered
thereby as shown in Fig. 24. Accordingly, foreign matter such as dirt and dust is
hard to deposit on the contacts 316a, 316a of the short circuit electrode 316. To
visibly check if foreign matter has been deposited on the contacts 316a, 316a of the
short circuit electrode 316, the cover 320 is slid rearward to the opening position
to thereby expose the contacts 316a, 316a as shown in Fig. 25. As a result, the conditions
of the contacts 316a, 316a can be inspected visibly. Upon completion of the visible
inspection, the cover 320 is moved back frontward to the protecting position as shown
in Fig. 24. Thus, the contacts 316a, 316a of the short circuit electrode 316 can be
protected and inspected easily as well as reliably, which in turn facilitates quality
control.
[0053] In addition, to connect the connector 310 on the female side to the connector 330
on the male side, the connector 130 on the female side is inserted into the hood portion
331 of the connector 330 on the male side. As a result, as shown in Fig. 26, at the
initial stage of the insertion, the engagement portion 335 at the distal ends of the
detecting electrodes 333, 333 comes in contact with the upper surface of the short
circuit electrode 316 to thereby elastically deform the short circuit electrode 316
together with the flexible lock piece 312 downward, so that the detecting electrodes
333, 333 are kept distant from the short circuit electrode 316.
[0054] As the connector 310 is further inserted into the connector 330, as shown in Fig.
27, the front end of the engagement portion 335 comes in contact with the front end
of the protective plate portion 321. As the connector 310 is still further inserted
into the connector 330, the engagement portion 335 pushes the cover 320 so that the
cover 320 moves rearward with the detecting electrodes 333, 333 not being in contact
with the short circuit electrode 316.
[0055] Upon complete connection of the both connectors 310, 330, the cover 320 pushed by
the engagement portion 335 moves to the opening position, which moves the engagement
portion 335 to such a position as to be engageable with the engagement hole 317 of
the short circuit electrode 316 and thereby releases the pushing of the engagement
portion 335 toward the flexible lock piece 312 and the short circuit electrode 316.
Accordingly, the flexible lock piece 312 and the short circuit electrode 316 return
upward by the restitutive force, and as shown in Fig. 28, not only the engagement
portion 335 gets engaged with the engagement hole 317, but also the distal ends 333a,
333a of the detecting electrodes 333, 333 come in contact with the contacts 316a,
316a of the short circuit electrode 316.
[0056] Since the rear end of the engagement portion 335 becomes engageable with the front
end of the engagement hole 317 upon engagement of the engagement portion 335 with
the engagement hole 317, both connectors 310, 330 are locked so as not to be movable
in such a direction as to be released from each other. When the short circuit electrode
316 comes in contact with the detecting electrodes 333, 333, both detecting electrodes
333, 333 are short-circuited, which causes the detecting circuit to detect the short-circuiting
and hence the correct locking of both connectors 310, 330.
[0057] During this connecting operation, the cover 320 set to the protecting position is
pushed by the engagement portion 335 to move to such a position as to expose the contacts
316a, 316a of the short circuit electrode 316. Therefore, no extra step of removing
the cover 320 from the connector 310 on the female side before starting the connecting
operation is required. Hence, efficiency in the entire connecting operation is improved.
[0058] In addition, unless both connectors 310, 330 are locked with the engagement portion
335 engaged with the engagement hole 317, the detecting electrodes 333, 333 never
come in contact with the short circuit electrode 316. Therefore, there is no danger
of mistaking a false locking of the connectors with the detecting electrodes 333,
333 coming in false contact with the short circuit electrode 316 for a correct locking.
[0059] It should be noted that the present device is not limited to the aforementioned embodiment
and, therefore, that various modifications may be made without departing from the
spirit of the present device.