Card edge connector

Information

  • Patent Grant
  • 6547577
  • Patent Number
    6,547,577
  • Date Filed
    Friday, December 28, 2001
    22 years ago
  • Date Issued
    Tuesday, April 15, 2003
    21 years ago
Abstract
In order to prevent terminal fittings of a card edge connector from short circuiting, a housing 11 is provided with a short circuit preventing member 50 made from insulating material. This short circuit preventing member 50 can be moved between a short circuit preventing position, between resilient contacts 42 of terminal fittings 40 provided at mutually opposing upper and lower locations, and a retreated position, which is to the posterior of the short circuit preventing position. Since the upper and lower terminal fittings 40 are prevented from short circuiting when the short circuit preventing member 50 is in the short circuit preventing position, the resilient contacts 42 are bendable to a greater degree, thus increasing their contacting force with contacts of a card edge connector.
Description




TECHNICAL FIELD




The present invention relates to a card edge connector.




BACKGROUND TO THE INVENTION





FIGS. 47 and 48

of this specification show a card edge connector


100


which is described in JP 56-136480. An anterior face of the card edge connector


100


is provided with a base plate insertion hole


102


into which an end of a base plate


101


can be inserted. The interior of the card edge connector


100


has a pair of terminal fittings


104


which are provided with resilient contacts


103


, and which are located symmetrically on either side of the base plate insertion hole


102


. The distance L separating the two resilient contacts


103


is less than the thickness M of the base plate


101


. When the base plate


101


has been attached to the card edge connector


100


, the two resilient contacts


103


resiliently grip the base plate


101


while making contact with thin film-like terminals


105


provided on both faces of the base plate


101


.




In this card edge connector


100


, the contacting resistance between the terminal fittings


104


and the terminals


105


is stabilised by increasing the contacting force between the resilient contacts


103


and the terminals


105


. If the resilient contacts


103


are caused to bend to a greater degree in order to achieve this aim, the distance L therebetween decreases. As a result, these upper and lower resilient contacts


103


may be more likely to make mutual contact before the base plate


101


is attached, thereby causing a circuit (not shown) of the card edge connector


100


to short circuit.




The present invention has taken the above problem into consideration, and aims to present a card edge connector wherein terminal fittings are not short circuited.




SUMMARY OF THE INVENTION




According to the invention there is provided a card edge connector comprising a housing having a slot adapted to receive the edge of a card having surface contacts, and opposed resilient terminals within said slot for contact with said surface contacts, said connector further including short circuit preventing member of electrically insulating material, said preventing member being movable from an advanced position between said opposed terminals to a retreated position not between said opposite terminals.




Preferably the preventing member is movable by direct contact with a card edge connector inserted into said slot.




Such an arrangement reliably prevents short-circuiting of the opposed terminals, and accordingly these terminals can be given an increased contact force so that a reliable engagement of the card edge contacts is assured.




In a preferred embodiment the preventing member is latchable in the advanced and retreated positions, and may be entrained for movement with a card edge connector between predetermined limits. The latter feature ensures that the preventing member is returned to the advanced condition should the connector be separated from the contacts of a card edge.











BRIEF DESCRIPTION OF THE DRAWING




Other features of the invention will be apparent from the following description of preferred embodiments shown by way of example only in the accompanying drawings in which:





FIG. 1

is a side cross-sectional view of a card edge connector of a first embodiment prior to being fitted together.





FIG. 2

is another side cross-sectional view showing the card edge connector prior to being fitted together.





FIG. 3

is a front view of the card edge connector.





FIG. 4

is a side face view of the card edge connector.





FIG. 5

is a plan cross-sectional view of a housing and a short circuit preventing member.





FIG. 6

is a rear face view of the housing.





FIG. 7

is a front view of a corresponding connector.





FIG. 8

is a front view of the short circuit preventing member.





FIG. 9

is a plan cross-sectional view of the short circuit preventing member.





FIG. 10

is a side face view of the short circuit preventing member.





FIG. 11

is a plan cross-sectional view showing a state whereby retaining arms have been bent by returning protrusions.





FIG. 12

is a side cross-sectional view showing the short circuit preventing member in a short circuit preventing position.





FIG. 13

is a plan cross-sectional view showing the short circuit preventing member in the short circuit preventing position.





FIG. 14

is a side cross-sectional view showing the short circuit preventing member being moved between the short circuit preventing position and a retreated position.





FIG. 15

is a plan cross-sectional view showing the short circuit preventing member being moved between the short circuit preventing position and the retreated position.





FIG. 16

is a side cross-sectional view showing a correctly fitted state.





FIG. 17

is a side cross-sectional view showing the correctly fitted state.





FIG. 18

is a plan cross-sectional view showing the correctly fitted state.





FIG. 19

is a side cross-sectional view of a card edge connector of a second embodiment prior to being fitted together.





FIG. 20

is a front view of a short circuit preventing member.





FIG. 21

is a rear face view of a housing.





FIG. 22

is a side face view of the card edge connector.





FIG. 23

is a plan cross-sectional view of the housing and the short circuit preventing member.





FIG. 24

is a plan cross-sectional view showing a state whereby retaining arms have been bent by returning protrusions.





FIG. 25

is a side cross-sectional view showing the short circuit preventing member being moved between a short circuit preventing position and a retreated position.





FIG. 26

is a side cross-sectional view showing a correctly fitted state.





FIG. 27

is a plan cross-sectional view showing the correctly fitted state.





FIG. 28

is a side cross-sectional view of a third embodiment of the present invention prior to being fitted together.





FIG. 29

is a side cross-sectional view showing fixing portions of a short circuit preventing member of the present invention prior to being fitted together.





FIG. 30

is a front view of a housing.





FIG. 31

is a side face view of the housing.





FIG. 32

is a plan cross-sectional view of the housing.





FIG. 33

is a rear face view of the housing.





FIG. 34

is a front view of a corresponding housing.





FIG. 35

is a front view of the short circuit preventing member.





FIG. 36

is a base face view of the short circuit preventing member.





FIG. 37A

is a side corss-sectional view along the line A—A of FIG.


8


.





FIG. 37B

is a side cross-sectional view along the line B—B of FIG.


8


.





FIG. 38

is a plan cross-sectional view showing a state whereby retaining arms have been bent by returning protrusions.





FIG. 39

is a side cross-sectional view showing base plates making contact with the short circuit preventing member.





FIG. 40

is a plan cross-sectional view showing the base plates making contact with the short circuit preventing member.





FIGS. 41A and 41B

are partially expanded cross-sectional views showing the vicinity of contacting protruding ends of the base plate and the short circuit preventing member.





FIG. 42

is a side cross-sectional view showing the short circuit preventing member being moved between a short circuit preventing position and a retreated position.





FIG. 43

is a plan cross-sectional view showing the short circuit preventing member being moved between the short circuit preventing position and the retreated position.





FIG. 44

is a side cross-sectional view showing a correctly fitted state.





FIG. 45

is a side cross-sectional view showing the position fixing portions of the short circuit preventing member in the correctly fitted state.





FIG. 46

is a plan cross-sectional view showing the correctly fitted state.





FIG. 47

is a partial cross-sectional diagonal view of a prior art card edge connector.





FIG. 48

is a side cross-sectional view of the prior art card edge connector.











DESCRIPTION OF PREFERRED EMBODIMENTS




A first embodiment of the present invention is described below with the aid of

FIGS. 1

to


18


.




As shown in

FIGS. 1

to


6


, a card edge connector


10


of the present embodiment is provided with a plastic housing


11


, terminal fittings


40


which can be inserted into the housing


11


, retainers


30


A and


30


B which are attached to the housing


11


as an upper and lower pair and which retain the terminal fittings


40


, and a short circuit preventing member


50


which prevents the terminal fittings


40


from short circuiting. The housing


11


fits with a corresponding housing


60


provided with a pair of base plates


61


A and


61


B. In the following description, fittings sides of the two housings


11


and


60


are considered to be the anterior face sides. Furthermore, only a portion of the corresponding housing


60


is shown.




The housing


11


, which is approximately box shaped and is along and narrow in a left-right direction, fits into a hood


62


of the corresponding housing


60


. A groove


12


is formed in an upper face of the housing


11


in the vicinity of the centre, relative to the left-right direction thereof. A locking arm


13


, which is capable of bending in an up-down direction, is provided in this groove


12


. When the two housings


11


and


10


have been fitted together, the locking arm


13


engages resiliently with a lock receiving member


63


provided on the hood


62


, this locking the two housings


11


and


60


in a latched state. The base plates


61


A and


61


B, which are aligned in a left-right direction, protrude from an inner face of the hood


62


, from a central location thereof relative to the up-down direction. A pair of base plate insertion holes


14


A and


14


B open into an anterior face of the housing


11


at locations corresponding to the base plates


61


A and


61


B. Fitting the two housings


11


and


60


together causes the base plates


61


A and


61


B to be inserted into the base plate insertion holes


14


A and


14


B respectively.




The housing


11


is provided with a plurality of cavities


16


which are aligned symmetrically above and below the base plate insertion holes


14


A and


14


B. Upper and lower terminal fittings


40


can be inserted into these cavities


16


. Thin film-like terminals (not shown) are provided in upper and lower faces of ends of the base plates


61


A and


61


B which are inserted into the base plate insertion holes


14


A and


14


B. These thin terminals are formed from copper foil, or the like. The cavities


16


, which are located so as to correspond these terminals, are long and narrow in an anterior-posterior direction, posterior ends thereof being open to allow the terminal fittings


40


to be inserted therefrom. The upper and lower rows of cavities


16


are symmetrical. A lance


17


protrudes inwards from an inner wall of each cavity


16


(from the outermost inner wall). These lances


17


are capable of bending in an up-down direction. Tips thereof engage resiliently with the terminal fittings


40


, thereby preventing their removal.




A pair of concave retainer attachment holes


18


A and


18


B, within which the retainers


30


A and


30


B are fitted, are formed in upper and lower faces respectively of the housing


11


at locations somewhat towards the posterior end thereof. The retainer attachment holes


18


A and


18


B adjoin the cavities and extend across the entire width of the housing


11


. The retainers


30


A and


30


B are cross-sectional U-shaped and are attached so as to straddle the housing


11


from left to right. Although a detailed description of the retainers


30


A and


30


B is omitted, they are formed such that they retain the terminal fittings


40


and are capable of moving between a temporary retaining position, this allowing the terminal fittings


4




o


to be removed from or inserted into the cavities


16


, and a main retaining position, whereby the retainers


30


A and


30


B are inserted more deeply than in the temporary retaining position and in which they engage with the terminal fittings


40


, thereby preventing their removal.




Each terminal fitting


40


is formed by bending electrically conductive sheet metal. A posterior portion thereof is provided with an electric wire connecting member


41


, to which an end of an electric wire W can be connected. An anterior end thereof is provided with a resilient contact


42


which makes resilient contact with the base plates


61


A and


61


B. With reference to the terminal fitting


40


of the lower cavity


16


shown in

FIG. 1

, the resilient contact


42


is shaped such that a ribbon-shaped portion thereof that extends beyond an anterior end of a base face of the terminal fitting


40


is bent obliquely upwards and towards the posterior, then an end thereof is again bent obliquely downwards and towards the anterior. An upper end of each resilient contact


42


forms a contacting member


42


A. The upper and lower terminal fittings


40


are located symmetrically such that the contacting members


42


A of the resilient contacts


42


thereof protrude towards one another. Furthermore, the contacting members


42


A of the upper and lower terminal fittings


40


protrude into the base plate insertion holes


14


A and


14


B respectively. When the base plates


61


A and


61


B respectively are inserted into these base plate insertion holes


14


A and


14


B, the contacting members


42


A resiliently grip the base plates


61


A and


61


B and make electrical contact with the terminals provided on both faces thereof.




A member housing hole


21


, which is capable of housing the short circuit preventing member


50


, is provided in the housing


11


. As shown in

FIG. 6

, this member housing hole


21


has an inverted U-shape when viewed from the posterior, and is open to the posterior of the housing


11


. The central portion of the member housing hole


21


divided the interior of the housing


11


into upper and lower portions, this member housing


21


also separating the upper and lower rows of cavities


16


. The base plate insertion holes


14


A and


14


B and an anterior portion of the member housing hole


21


extend partially along a common domain. The left and right side ends of the member housing hole


21


form side grooves


21


A that extend downwards. As shown in

FIG. 4

, window holes


22


pass through left and right side faces of the housing


11


, these adjoining portions of the side grooves


21


A.




The short circuit preventing member


50


, which is shown in

FIGS. 8

to


10


, is made from insulating plastic, has a cross-sectional U-shape, and is provided with an approximately flat isolating member


51


and a pair of side wall members


52


that protrude downwards from let and right side ends of the isolating member


51


. The short circuit preventing member


50


is fitted from the posterior into the member housing hole


21


. When located within the member housing hole


21


, the isolating member


51


separates the upper and lower cavities


26


, and the left and right side wall members


52


are housed within the side grooves


21


A. The member housing hole


21


is smaller in dimension, in the up-down direction, than the base plate insertion holes


14


A and


14


B. Further, the isolating member


51


of the short circuit preventing member


50


is slightly thinner than the base plates


61


A and


61


B. Moreover, in the anterior-posterior direction, the short circuit preventing member


50


is shorter than the member housing hole


21


, the short circuit preventing member


50


being capable of sliding in the anterior-posterior direction therein.




When within the member housing


21


, the short circuit preventing member


50


can be located in a short circuit preventing position (shown in

FIGS. 1

,


2


,


5


, etc.), whereby the short circuit preventing member


50


is located at the anterior end of the member housing hole


21


, or a retreated position (shown in

FIGS. 16

,


17


and


18


), whereby the short circuit preventing member


50


is located at the posterior end of the member housing hole


21


. In the short circuit preventing position, the isolating member


51


is located within the base plate insertion holes


14


A and


14


B, between the resilient contacts


42


of the upper and lower terminal fittings


40


, thereby preventing these terminal fittings


40


from short circuiting. In this position, an anterior face wall


24


of the housing


11


prevents the short circuit preventing member


50


from moving towards the anterior. In the retreated position, the isolating member


51


is located to the posterior relative to the resilient contacts


42


of the upper and lower terminal fittings


40


, in a position removed therefrom.




As shown in

FIG. 10

, the side wall members


52


of the short circuit preventing member


50


have cut-away grooves


53


formed therein, these extending in an anterior-posterior direction from locations near the lower ends thereof. The provision of these cut-away grooves


53


results in bending edges


54


being formed in the lower edges of the side wall members


52


, central portions of these bending edges


54


being capable of bending in an up-down direction. A position fixing protrusion


55


protrudes downwards from a central portion of each bending edge


54


. As shown in

FIG. 2

, position fixing holes


23


are formed in base faces of the side grooves


21


A of the member housing hole


21


. The position fixing protrusions


55


engage with these position fixing holes


23


, thereby maintaining the short circuit preventing member


50


in the short circuit preventing position. Further, position fixing holes


31


are formed in the lower retainer


30


B which is attached at a location to the posterior of the position fixing holes


23


. These position fixing holes


31


are provided at locations corresponding to the vase faces of the side grooves


21


A, the position fixing protrusions


55


being capable of engaging with these position fixing holes


31


. When the position fixing protrusions


55


engage with the position fixing holes


31


, the short circuit preventing member


50


is maintained in the retreated position.




An anterior end of each cut-away grooves


53


of the side wall members


52


extends upwards and then towards the posterior towards the vicinity of the central portion thereof. A portion of each side wall member


52


which is surrounded by the cut-away groove


53


forms a retaining arm


57


(this corresponds to the retaining means of the present invention) that extends towards the anterior. These retaining arms


57


are capable of bending in the widthwise direction of the short circuit preventing member


50


. A retaining protrusion


58


is formed on a tip of each retaining arm


57


, this protruding outwards relative to the widthwise direction. When the retaining arms


57


are in a natural, unbent, state (see FIG.


5


), the retaining protrusions


58


protrude outwards from the window holes


22


of the housing


11


. A bending regulating protrusion


59


protrudes upwards from a tip of each retaining protrusion


58


.




As shown in

FIG. 11

, recesses


25


are formed in a concave manner in inner side faces, relative to the widthwise direction, of the side grooves


21


A of the housing


11


. These recesses


25


allow the retaining arms


57


to bend. As shown in

FIG. 15

, long and narrow bending regulating walls


26


extend in an anterior-posterior direction along inner side walls (relative to the widthwise direction) of the side grooves


21


A. These bending regulating walls


26


make contact with inner sides, relative to the widthwise direction, of the bending regulating protrusions


59


, thereby controlling the bending of the retaining arms


57


. The recesses


25


are provided at the anterior ends of the bending regulating walls


26


. When the short circuit preventing member


50


is located to the posterior (relative to the short circuit preventing position), the retaining arms


57


are in a state whereby they cannot be bent. When the short circuit preventing member


50


is in the short circuit preventing position (see FIG.


5


), the bending regulating protrusions


59


are located to the anterior of the bending regulating walls


26


, thereby allowing the retaining arms


57


to bend.




As shown in

FIGS. 7 and 13

, a pair of returning protrusions


65


are formed on left and right inner side faces of the hood


62


of the corresponding housing


60


. When the two housings


11


and


60


have been fitted together, these returning protrusions


65


engage, from the posterior, with the retaining protrusions


58


.




The present embodiment is configures as described above. Next, the operation thereof will be described.




When the two housings


11


and


60


are in a state prior to being fitted together (see FIGS.


1


and


2


), the short circuit preventing member


50


is located between the upper and lower resilient contacts


42


, the contacting members


42


A of these resilient contacts


42


making resilient contact with the short circuit preventing member


50


. By this means, the terminal fittings


40


, which are located in mutually corresponding positions above and below, are prevented from short circuiting.




When the two housings


11


and


60


are fitted together from this state, the housing


11


is fitted into the corresponding hood


62


. At this juncture, the returning protrusions


65


strike against the bending regulating protrusions


59


(see FIG.


11


), bending the retaining arms


57


into the recesses


25


. Moreover, tips of the base plates


61


A and


61


B are inserted into the base plate insertion holes


14


A and


14


B respectively.




As fitting progresses, the returning protrusions


65


rise over the bending regulating protrusions


59


, the retaining arms


57


returning to their original shape and being released from the recesses


25


(the state shown in FIGS.


12


and


13


). By this means, the returning protrusions


65


engage from the posterior with the retaining protrusions


58


. Simultaneously, tip ends of the base plates


61


A and


61


B strike against an anterior end of the short circuit preventing member


50


.




As fitting progresses further, the short circuit preventing member


50


is pushed towards the posterior by the base plates


61


A and


61


B while these base plates


61


A and


61


B are being inserted into the base plate insertion holes


14


A and


14


B (this state is shown in FIGS.


14


and


15


). Then, the central portions of the bending edges


54


of the side wall members


52


of the short circuit preventing member


50


bend upwards, and the position fixing protrusions


55


rise over the base faces of the side grooves


21


A. In this state, the short circuit preventing member


50


is moved into the retreated position.




Next, the short circuit preventing member


50


is removed from between the resilient contacts


42


of the upper and lower terminal fittings


40


. The tip ends of the base plates


61


A and


6





1


B make contact with the upper and lower resilient contacts


42


, enter therebetween and bend these resilient contacts


42


in a direction of mutual separation. The base plates


61


A and


61


B are now resiliently gripped between the contacting members


42


A of the upper and lower resilient contacts


42


.




When the two housings


11


and


60


have been fitted together in a correct position, the locking arm


13


engages with the lock receiving member


63


, this locking the two housings


11


and


60


in a fitted state (the state shown in

FIGS. 16

to


18


). Furthermore, the bending edges


54


of the side wall members


52


of the short circuit preventing member


50


return to their original position, and the position fixing protrusions


55


of the short circuit preventing member


50


fit into and are engaged with the position fixing holes


31


of the lower retainer


30


B, this maintaining the short circuit preventing member


50


in the retreated position. Further, the base plates


61


A and


61


B are resiliently gripped between the contacting members


42


A of the upper and lower resilient contacts


42


, these contacting members


42


A making contact with the terminals provided on both faces of the base plates


61


A and


61


B, and each circuit (not shown) contact. In this manner, the fitting operation of the two housings


11


and


60


is completed.




In the case where the two housings


11


and


60


are to be separated from a fitted state, the locking arm


13


is first pushed downwards, this releasing is from its engagement with the lock receiving member


63


. Then, from this state, the two housings


11


and


60


are pulled in a direction of mutual separation. As this is done, the base plates


61


A and


61


B leave the base plate insertion holes


14


A and


14


B, and the returning protrusions


65


push the retaining protrusions


58


in a direction of separation. At this juncture, the bending regulating walls


26


make contact with the inner sides, relative to the widthwise direction thereof, of the bending regulating protrusions


59


, thereby preventing the retaining arms


57


from bending. Consequently, the returning protrusions


65


and the retaining protrusions


58


are maintained in their engages state. As a result, the short circuit preventing member


50


moves towards the anterior while the base plates


61


A and


61


B are being removed from the base plate insertion holes


14


A and


14


B (see FIGS.


14


and


15


). Furthermore, the central portions of the bending edges


54


of the side wall members


52


bend, the position fixing protrusions


55


being removed from the position fixing holes


31


of the lower retainer


30


B. The base plates


61


A and


61


B and the short circuit preventing member


50


are moved while their tips are in a mutually contacting state. When the base plates


61


A and


61


B are removed from between the resilient contacts


42


of the upper and lower terminal fittings


40


, these upper and lower resilient contacts


42


move slightly towards one another, then make resilient contact with the short circuit preventing member


50


.




When the short circuit preventing member


50


reaches the short circuit preventing position, it makes contact with the anterior face wall


24


of the housing


11


. This prevents the short circuit preventing member


50


from moving towards the anterior.




Furthermore, the position fixing protrusions


55


are engaged with the position fixing holes


23


, thereby maintaining the position of the short circuit preventing member


50


(the state shown in FIGS.


12


and


13


). At this juncture, the bending regulating protrusions


59


are located to the anterior of the bending regulating walls


26


, in a location whereby they do not interfere therewith.




When the two housings


11


and


60


are separated further, the returning protrusions


65


push the bending regulating protrusions


59


(see FIG.


11


), the retaining arms


57


are moved into the recesses


25


, and the returning protrusions


65


are released from the retaining protrusions


58


.




Then, the base plates


61


A and


61


B are removed from the base plate insertion holes


14


A and


14


B, the retaining protrusions


58


rise over the returning protrusions


65


and the retaining arms


57


return to their original position. Thereupon, the housing


11


is removed from the hood


62


, and the two housings


11


and


60


return to their state prior to being fitted together (see

FIGS. 1

,


2


and


5


).




In this manner, the card edge connector


10


of the present embodiment has the short circuit preventing member


50


located between the resilient contacts


42


of the mutually opposing upper and lower terminal fittings


40


, this preventing the terminal fittings


40


from short circuiting. As a result, the resilient contacts


42


can be caused to bend to a greater degree, thus increasing their contacting force with the base plates


16


A and


61


B.




Furthermore, the short circuit preventing member


50


is moved from the short circuit preventing position to the retreated position as the base plates


61


A and


61


B are being pushed in (while the two housings


11


and


60


are being fitted together). Operability is thereby simplified. In particular, since the base plates


61


A and


61


B push the short circuit preventing member


50


directly, no other components need be provided to perform this pushing operation.




Moreover, the short circuit preventing member


50


returns from the retreated position to the short circuit preventing position, so as to prevent the terminal fittings


40


from short circuiting, as the base plates


61


A and


61


B are being removed (while the two housings


11


and


60


are being separated.) Operability is thereby simplified.




The short circuit preventing member


50


is thinner than the base plates


61


A and


61


B. Consequently, the resilient contacts


42


bend only a little when they make contact with the short circuit preventing member


50


. This prevents fatigue of the resilient contacts


42


in the case where the short circuit preventing member


50


is left in the retreated position for a long period.




If resilient contacts are bent to a great degree, the resisting force increases when base plates are inserted. However, in the card edge connector


10


described above, the base plates


61


A and


61


B and the short circuit preventing member


50


are maintained in a contacting state while the two housings


11


and


60


are fitted together, the base plates


61


A and


61


B entering between the upper and lower resilient contacts


42


and taking the place of the short circuit preventing member


50


. That is, the resilient contacts


42


move without interruption from a state whereby they are bent as a result of making contact with the short circuit preventing member


50


, to a state whereby they are bent more as a result of making contact with the base plates


61


A and


61


B. Consequently, compared to the case where base plates are inserted between resilient contacts which are in a natural, unbent, state, the resilient contacts of the present embodiments are bent to a lesser degree when the base plates are inserted. Consequently, less resisting force occurs during insertion.




A second embodiment of the present invention is described below with the aid of

FIGS. 19

to


27


. In the following description, configurations which are the same as in the first embodiment are accorded the same symbols and an explanation thereof is omitted.




As shown in

FIG. 20

, a short circuit preventing member


70


of a card edge connector


80


of the present embodiment is cross-sectionally H-shaped. This short circuit preventing member


70


is provided with an approximately flat isolating member


71


and a pair of side wall members


72


that protrude upwards and downwards from left and right side ends of the isolating member


71


. The isolating member


71


is slightly thinner than the base plates


61


A and


61


B. As shown in

FIG. 19

, upper portions of the side wall members


72


have cut-away grooves


73


formed therein, these extending in an anterior-posterior direction. The provision of these cut-away grooves


73


results in bending edges


74


being formed in upper edges of the side wall members


52


, central portions of these bending edges


74


being capable of bending in an up-down direction. A position fixing protrusion


75


protrudes upwards from a central portion of each bending edge


74


.




A member housing hole


82


, which is cross-sectionally H-shaped so as to correspond to the short circuit preventing member


70


, is provided in the housing


81


(see FIG.


21


). This member housing hole


82


is capable of housing the short circuit preventing member


70


. As in the first embodiment, the short circuit preventing member


70


can be slid between a short circuit preventing position and a retreated position within the member housing hole


82


. Left and right side ends of the member housing hole


82


form side grooves


82


A. As shown in

FIG. 22

, window holes


83


pass through left and right side faces of the housing


81


, these adjoining portions of the side grooves


82


A. Furthermore, as shown in

FIG. 19

, a pair of position fixing holes


84


A and


84


B are formed in an anterior-posterior direction in upper faces of the side grooves


82


A. The position fixing protrusions


75


engage with either the position fixing hole


84


A or the position fixing hole


84


B, thereby maintaining the short circuit preventing member


70


in position.




A U-shaped cut-away member


76


is formed in an anterior lower portion of each side wall member


72


of the short circuit preventing member


70


. A portion of each side wall member


72


which is surrounded by this cut-away member


76


forms a retaining arm


77


(this corresponds to the retaining means of the present invention) that extends from the anterior towards the posterior. These retaining arms


77


are capable of bending in the widthwise direction of the short circuit preventing member


70


. A retaining protrusion


78


if formed on a posterior end (a free end) of each retaining arm


77


, this protruding outwards relative to the widthwise direction. When the retaining arms


77


are in a natural, unbent, state (see FIG.


23


), the retaining protrusions


78


protrude outwards from the window holes


83


of the housing


81


. Recessed members


85


are formed in a concave manner in inner side faces, relative to the widthwise direction, of the side grooves


82


A of the housing


81


. These recessed members


85


allow the retaining arms


77


to bend. Side faces located to the posterior of the recessed members


85


form bending regulating walls


86


, these making contact with inner sides, relative to the widthwise direction, of the retaining arms


77


and thereby controlling their bending.




As shown in

FIGS. 19 and 24

, a pair of returning protrusions


92


are formed on left and right inner side faces of a hood


91


of a corresponding housing


90


. When the two housings have been fitted together, these returning protrusions


92


engage, from the posterior, with the retaining protrusions


78


.




The operation of the present embodiment is described below.




When the two housings


81


and


90


are fitted together from the state shown in

FIG. 19

, the returning protrusions


92


strike against the retaining protrusions


78


(see FIG.


24


), bending the retaining arms


77


into the recessed members


85


. Then, the returning protrusions


92


rise over the retaining protrusions


78


, the retaining arms


77


return to their original shape, and the returning protrusions


92


engage from the posterior with the retaining protrusions


78


. At approximately the same time, the base plates


61


A and


61


B, which have been inserted into base plate insertion holes


14


A and


14


B, strike against the short circuit preventing member


70


.




As fitting progresses, the base plates


61


A and


61


B push the short circuit preventing member


70


towards the posterior, the bending edges


74


bend towards the cut-away grooves


73


(see FIG.


25


), and the position fixing protrusions


75


rise over upper wall faces of the side grooves


82


A. When the two housings


81


and


90


have reached a correctly fitted state, the bending edges


74


return to their original positions, and the position fixing protrusions


75


fit into the posterior position fixing holes


84


B, thereby maintaining the short circuit preventing member


70


in a retreated position (see FIGS.


26


and


27


).




In the case where the two housings


81


and


90


are to be separated from the fitted state, they are pulled in a direction of mutual separation, the returning protrusions


92


pushing the retaining protrusions


78


in a direction of separation. At this juncture, the bending regulating walls


86


make contact with the inner sides, relative to the widthwise direction thereof, of the retaining arms


77


, thereby preventing these retaining arms


77


from bending. consequently, the returning protrusions


92


and the retaining arms


77


are maintained in their engaged state. As a result, the short circuit preventing member


70


moves towards the anterior. As shown in

FIG. 25

, the bending edges


74


of the side wall members


72


bend, and the position fixing protrusions


75


are removed from the posterior position fixing holes


84


B.




When the short circuit preventing member


70


has reached the short circuit preventing position, the bending edges


74


return to their original positions and the position fixing protrusions


75


engage with the anterior position fixing holes


84


A, thereby fixing the position of the short circuit preventing member


70


. When the two housings


81


and


90


are separated further, the returning protrusions


92


push the retaining protrusions


78


(see FIG.


24


), the retaining arms


77


move into the recessed members


85


, and the returning protrusions


92


are released from the retaining arms


77


. Then, the retaining protrusions


78


rise over the returning protrusions


92


and the retaining arms


77


return to the original position. Thereupon, the two housings


81


and


90


return to their state prior to being fitted together (see FIGS.


19


and


23


).




The present embodiment has the same operation and effects as the first embodiment, but does not have the bending regulating protrusions


59


on the upper faces of the retaining arms


57


that are provided in the first embodiment. Consequently, the retaining arms


77


of the second embodiment are smaller, in the up-down direction, by the extent of these bending regulating protrusions


59


. As a result, the recessed members


85


(into which the retaining arms


77


bend) of the housing


81


are also smaller in the up-down direction. Consequently, the card edge connector


80


can be miniaturised as a whole.




Another embodiment of the present invention is described below with the aid of

FIGS. 28

to


46


, corresponding components have the same reference numerals as in the first embodiment, but preceded by 2.




The housing


211


fits with a corresponding housing


270


made from plastic and protruding in a unified manner from a side face of a piece of machinery or the like. In the following description, fitting sides of the two housings


211


and


270


are considered to be the anterior face sides.




This housing


211


fits into a hood


271


of the corresponding housing


270


. When the two housings


211


and


270


have been fitted together, the locking arm


213


engages resiliently with a lock receiving member


272


upper portion of the hood


271


.




Two left and right base plates


274


protrude from an inner face of the hood


271


.




Two base plate insertion holes


214


open into an anterior face of the housing


211


at locations whereby the base plates


274


can be inserted therein from the anterior. These base plate insertion holes


214


extend to approximately the centre of the housing


211


, relative to the lengthwise direction thereof. Thin film-shaped terminals (not shown) are provided on upper and lower faces of anterior end portions of the base plates


274


.




A pair of concave retainer attachment holes


218


, within which the retainers


230


are fitted, are formed in upper and lower faces of the housing


211


.




The short circuit preventing member


250


is attached within the housing


211


. For this purpose, a member housing hole


221


, which is capable of housing the short circuit preventing member


250


, is provided in a posterior face of the housing


211


. This member housing hole


221


has an inverted U-shape when viewed cross-sectionally. The horizontal portion of the member housing


221


separate the upper and lower rows of cavities


216


. A joining groove


224


passes through a central wall


223


of the member housing hole


221


to inner sides of the base plate insertion holes


14


. This joining groove


224


has a height such that an isolating member


251


(to be described in detail later) of the short circuit preventing member


250


can be inserted tightly therein. Portions of the ceiling face and the base face of the joining groove


224


are open to the upper and lower cavities


216


, this allowing the resilient contacts


242


of the terminal fittings


240


to pass therethrough. The left and right side ends of the member housing hole


221


form side grooves


222


that extend downwards. Window holes


226


pass through left and right side faces of the housing


211


, these opening onto portions of the side grooves


222


.




The isolating member


251


is thinner than the base plate


274


, having a thickness whereby it can be inserted tightly into the joining groove


224


of the central wall


223


.




Guiding grooves


253


, which extend in an anterior-posterior direction, are formed in upper and lower faces of the short circuit preventing member


250


at locations corresponding to the cavities


216


. The contacting members


42


A of the resilient contacts


242


of the terminal fittings


240


are fitted into these guiding grooves


253


, the sliding of these contacting members


242


A thereby being guided. As shown in

FIG. 210

, a portion of an anterior end of each guiding groove


253


forms a thick member


254


that is approximately twice as thick as the guiding groove


253


and joins therewith via oblique members


256


. A concave member


255


is formed in an anterior face of each thick member


254


at a central location thereof relative to the up-down direction. A burr x (to be described) can enter this concave member


255


.




Portions of the anterior ends of the short circuit preventing member


250


that are not provided with thick members


254


are retreated as far as inner faces of the concave members


255


. An anterior end of each thick member


254


is considered to be the anterior end of the short circuit preventing member


250


when this is in a contacting state.




The short circuit preventing member


250


is attached such that it can slide freely in an anterior-posterior direction from the member housing hole


221


to the base plate insertion holes


214


. It can be maintained either in a short circuit preventing position (located at the anterior) or in a retreated position (located at the posterior). When the short circuit preventing member


250


is in the short circuit preventing position, the isolating member


251


thereof is positioned between the resilient contacts


242


of the terminal fittings


240


protruding upwards and downwards into the base plate insertion holes


214


, thereby separating these resilient contacts


242


. When the short circuit preventing member


250


is in the retreated position, the isolating member


251


has retreated to a location to the posterior of the resilient contacts


242


of the upper and lower terminal fittings


240


.




Slits are formed in inner sides of lower end portions of the side wall members


252


of the short circuit preventing member


250


, thus forming bending members


257


. A retaining protrusion


258


protrudes from an approximately central portion of a lower face of each bending member


257


. A position fixing hole


227


is formed in a base face of each of the side grooves


222


of the member housing


221


. Anterior ends of the side wall members


252


make contact with the side grooves


222


, and the retaining protrusions


258


fit into the position fixing holes


227


, thereby maintaining the short circuit preventing member


250


in the short circuit preventing position. Further, other position fixing holes


231


are formed in the lower retainer


230


which is attached at a location to the posterior of the position fixing holes


227


. These position fixing holes


231


are provided at locations corresponding to the base faces of the side grooves


222


. When the retaining protrusions


258


engage with the position fixing holes


231


, the short circuit preventing member


250


is maintained in the retreated position.




A retaining arm


260


is formed in each of the side wall members


252


at a location above the slits. These retaining arms


260


extend in a cantilevered shape towards the anterior from an approximately central location of each side wall member


252


, relative to the lengthwise direction thereof. These retaining arms


260


are capable of bending in a widthwise direction relative to the side wall members


252


. A retaining protrusion


261


, which protrudes outwards, is formed on a tip of each retaining arm


260


. When the retaining arms


260


are in a natural, unbent state the retaining protrusions


261


protrude into the window holes


226


of the housing


211


. A bending regulating protrusion


262


protrudes upwards from a tip of each retaining protrusion


261


.




Recessed members


228


are formed in a concave manner in inner faces of the side grooves


222


of the housing


211


. These recessed members


228


allow the retaining arms


260


to bend. As shown in

FIG. 216

, long and narrow bending regulating walls


229


extend in an anterior-posterior direction at the posterior of the recessed members


228


. These bending regulating walls


229


make contact with inner sides of the bending regulating protrusions


262


. When the short circuit preventing member


250


is located to the posterior relative to the short circuit preventing position, the bending regulating walls


229


prevent the retaining arms


260


from bending. When the short circuit preventing member


250


is in the short circuit preventing position, the bending regulating protrusions


262


are located to the anterior of the bending regulating walls


229


, this allowing the retaining arms


260


to bend.




A pair of returning protrusions


275


are formed in left and right inner side faces of the hood


271


of the corresponding housing


270


. When the two housings


211


and


270


have been fitted together, these returning protrusions


275


engage with the retaining protrusions


261


of the retaining arms


260


.




The present embodiment is confugured as described above. Next, the operation thereof will be described.




When the short circuit preventing member


250


is inserted from the posterior into the member housing hole


221


of the housing


211


, an anterior end of the isolating member


251


is pushed through the joining groove


224


of the central wall


223


, and the short circuit preventing member


250


is maintained in the short circuit preventing position. Then, the terminal fittings


240


are inserted from the posterior into the cavities


216


, the contacting members


242


A thereof sliding within the guiding grooves


253


of the short circuit preventing member


250


. After the terminal fittings


240


have been pushed in to a correct position, they are retained by the lances


217


. Then the retainers


230


are moved to the main retaining position, thereby doubly retaining the terminal fittings


240


. At this juncture, the isolating member


251


of the short circuit preventing member


250


enters between and separates the mutually facing upper and lower terminal fittings


240


, and the contacting members


242


A of the resilient contacts


242


make resilient contact with groove bases of the guiding grooves


253


. In this manner, the upper and lower terminal fittings


240


are prevented from short circuiting.




From this state, the housing


211


is fitted into the hood


271


of the corresponding housing


270


. While the two housings


211


and


270


are being fitted together, the returning protrusions


275


strike against the retaining protrusions


261


, this bending the retaining arms


260


into the recessed members


228


. Moreover, tips of the base plates


274


are inserted into the corresponding base plate insertion holes


214


.




As fitting progresses, the returning protrusions


275


pass over the retaining protrusions


261


, the retaining arms


260


returning to their original shape and being released from the recessed members


228


. By this means, the returning protrusions


275


engage from the posterior with the retaining protrusions


261


. At approximately the same time, anterior ends of the base plates


274


strike against the anterior end of the isolating members


251


of the short circuit preventing member


250


.




The anterior ends of the base plates


274


are sheared off in the direction of the thickness of these plates, this making it highly likely that burrs x will be formed. In this embodiment, the concave members


255


are formed in the portion of the anterior end of the short circuit preventing member


250


which is provided with the thick members


254


, these concave members


255


allowing the burrs x to enter therein. The remaining portions of the anterior end of the short circuit preventing member


250


are retreated towards the posterior. The burr x (if present) fits either into the concave members


255


or into the retreated portions of the short circuit preventing member


250


, the anterior ends of the base plates


274


making contact with the anterior ends of the thick members


254


. That is, the anterior ends of the base plates


274


make contact with the anterior ends of the thick members


254


in the same way as they would if no burr x were present.




As the fitting of the two housings


211


and


270


progresses further, the short circuit preventing member


250


is pushed towards the posterior by the base plates


274


while these base plates


274


are being inserted into the base plate insertion holes


214


. Then, the bending members


257


of the side wall members


252


of the short circuit preventing member


250


bend upwards, and the position fixing protrusions


258


rise over the base faces of the side grooves


222


. In this state, the short circuit preventing member


250


is moved into the retreated position. Simultaneously, the resilient contacts


242


of the upper and lower terminal fittings


240


bend, rising first over the oblique members


256


then over the upper and lower faces of the thick members


254


. As insertion continues, the resilient contacts


242


continue past the anterior ends of the base plates


274


which have been inserted. By this means, the contacting members


242


A of the upper and lower resilient contacts


242


resiliently grip the base plates


274


.




When the housing


211


has reached a correct position, the locking arm


213


engages with the lock receiving member


272


of the corresponding housing


270


, this locking the two housings


211


and


270


in a fitted state. Furthermore, the bending members


257


of the side wall members


252


of the short circuit preventing member


250


return to their original position, and the position fixing protrusions


258


fit into and engage with the position fixing holes


231


of the lower retainer


230


, this maintaining the short circuit preventing member


250


in the retreated position. At this juncture, the base plates


274


are resiliently gripped between the contacting members


242


A of the upper and lower resilient contacts


242


, these contacting members


242


A making contact with the terminals provided on the faces of the base plates


274


, and each circuit between the terminal fittings


240


and the base plates


274


making electrical contact. In this manner, the fitting operation of the two housings


211


and


270


is completed.




In the case where the two housings


211


and


270


are to be separated from a fitted state, the locking arm


213


is first pushed downwards, this releasing it from its engagement with the lock receiving member


272


. Then, from this state, the housing


211


is pulled towards the posterior. As this is done, the base plates


274


leave the base plate insertion holes


214


, and the returning protrusions


275


engage with the retaining protrusions


261


. At this juncture, the bending regulating walls


229


make contact with the inner sides of the bending regulating protrusions


262


, thereby preventing the retaining arms


260


from bending. Consequently, the returning protrusions


275


and the retaining protrusions


261


are maintained in their engaged state. As a result, the short circuit preventing member


250


moves towards the anterior while the bending members


257


bend and the position fixing protrusions


258


are removed from the position fixing holes


231


of the retainer


230


.




The base plates


274


and the short circuit preventing member


250


are moved while their contacting protruding ends are in a mutually contacting state; then the anterior ends of the base plates


274


are removed from between the reislient contacts


242


of the upper and lower terminal fittings


240


. Next, after the upper and lower resilient contacts


242


have risen over both faces of the thick members


254


of the short circuit preventing member


250


, these resilient contacts


242


return to their original position, moving slightly towards one another while sliding along the oblique members


256


, then making resilient contact with the groove bases of the guiding grooves


253


.




When the short circuit preventing member


250


reaches the short circuit preventing position, it makes contact with the anterior faces of the side grooves


222


. This prevents the short circuit preventing member


250


from moving towards the anterior. Further, the position fixing protrusions


258


are engaged with the position fixing holes


227


located at the anterior, thereby maintaining the position of the short circuit preventing member


150


. Moreover, the bending regulating protrusions


262


are located to the anterior of the bending regulating walls


229


, in a location whereby they do not interfere therewith.




When the housing


211


is pulled out further, the returning protrusions


275


push the bending regulating protrusions


262


, the retaining arms


260


are moved into the recessed members


228


, and the engeged state of the returning protrusions


275


and the retaining protrusions


261


is released.




Then, the base plates


274


are removed from the base plate insertion holes


214


, the retaining protrusions


261


pass over the returning protrusions


275


and the retaining arms


260


return to their original position. In this manner, the housing


211


is removed from the hood


271


, and the two housings


211


and


270


return to their state prior to being fitted together.




In the present embodiment, the short circuit preventing member


250


is located between the terminal fittings


240


, this preventing them from short circuiting. As a result, the mutually opposing resilient contacts


242


can readily be caused to bend to a greater degree towards one another, thus increasing their contacting force with the terminals on the base plates


274


and allowing a stable contacting state to be obtained.




The anterior ends of the base plates


274


that push the short circuit preventing member


250


are likely to have burrs x formed thereon due to their being sheared off in the direction of the thickness of these plates. If these burrs x push portions of the anterior end of the isolating member


251


, this causes a space to form between the mutually contacting protruding ends of the base plates


274


and the short circuit preventing member


250


. Consequently, there is the problem that the resilient contacts


242


of the terminal fittings


240


may make contact via this space while the short circuit preventing member


250


is being pushed in.




The present embodiment addressed this problem by providing the concave members


255


in the thick members


254


at the anterior end of the isolating member


251


of the short circuit preventing members


250


, these concave members


255


allowing the burrs x to enter therein. The portion remaining (i.e. the portion of the isolationg member


251


not provided with the thick members


254


) is retreated towards the posterior. As a result, the burrs x (if present) fits either into the concave members


255


or into these retreated portions. That is, the anterior ends of the base plates


274


make contact with the anterior ends of the thick members


254


in the same way as they would if no burrs x were present.




As a result, almost no space is formed at the location where the upper and lower terminal fittings


240


are provided, between the contacting protruding ends of the base plates


274


and the isolating members


251


of the short circuit preventing member


250


. Consequently, the resilient contacts


242


of the upper and lower terminal fittings


240


do not make contact (that is, they do not short circuit).




Further, the burrs x are housed within the concave members


255


at the location where the upper and lower terminal fittings


240


are provided. Consequently, the burrs x will not come between the resilient contacts


242


and damage the electrical contact as a result of (for example) being torn off and coming to rest on the terminals.




Further, the burrs x (if present) cause the anterior ends of the base plates


274


to protrude to a greater extent, which causes these base plates


274


to being pushing the short circuit preventing member


250


at an earlier stage. In that case, the short circuit preventing member


250


may, for example, return to the retreated position before the two housings


211


and


270


have been correctly fitted together. At this juncture, mutual resistance would halt the fitting operation. That is, the fitting operation would halt before the two housings


211


and


270


have been locked together, this leaving the two housings


211


and


270


in an unstable state.




The present embodiment has addressed this problem by preventing the burrs x, if present, from causing the anterior ends of the base plates


274


to protrude further. Consequently, the base plates


274


push the short circuit preventing member


250


at the correct time, and the prescribed operations, such as locking the two housings


211


and


270


together, can be obtained.




The present invention is not limited to the embodiments described above with the aid of figures. For example, the possibilities described below also lie within the technical range of the present invention.




(1) In the embodiments described above, the short circuit preventing member can be moved, within the housing, between the short circuit preventing position and the retreated position. However, according to the present invention, the short circuit preventing member may equally well be located at the exterior of the housing when it is in the retreated position.




(2) In the embodiments described above, the base plates directly push the short circuit preventing member while they are being inserted. However, according to the present invention, a member other than the base plates (the corresponding housing, for example) may equally well push the short circuit preventing member. Further, the short circuit preventing member may be moved into the retreated position in an operation which is separate from the insertion of the base plates.




(3) In the embodiments described above, when the base plates are removed from the base plate insertion holes, the retaining means (the retaining arms and the returning protrusions) return the short circuit preventing member to the short circuit preventing position. However, according to the present invention, the short circuit preventing member can equally well be returned to the short circuit preventing position in an operation which is separate from the removal of the base plates.




(4) In the embodiments described above, the operations of fitting the two housings together and separating them (the operations of inserting and removing the base plates) is accompanied by the retaining means (the retaining arms and the returning protrusions) being mutually engaged and released. However, according to the present invention, this engaging and releasing can equally well occur as a separate operation.




(5) In the third embodiment contact of the upper and lower terminal fittings via the space between the mutually contacting protruding ends of the base plates and the short circuit preventing member may be prevented as long as this space does not extend in a straight line relative to the direction of thickness of the plates. For this reason, in order to prevent short circuiting, it is sufficient that the mutually contacting protruding ends of the base plates and the short circuit preventing member mutually overlap.



Claims
  • 1. A card edge connector comprising a housing having a slot adapted to receive the edge of a card having surface contacts, and opposed resilient terminals within said slot and adapted to grip said surface contacts, said connector further including a short circuit preventing member of electrically insulating material and a resilient latch, said preventing member being movable from an advanced position between said opposed terminals to a retreated position rearward of said opposite terminals, and said resilient latch being adapted to releasably retain said preventing member in the advanced and retreated positions.
  • 2. A connector according to claim 1 wherein said latch comprises a flexible arm of said preventing member, said arm being engageable in a recess of said housing.
  • 3. A connector according to claim 1 wherein said preventing member is directly movable by a card edge connector inserted into said slot.
  • 4. A connector according to claim 3 wherein said preventing member has a contact edge for direct engagement with said card edge connector, said contact edge having a depression extending laterally thereof.
  • 5. A connector according to claim 4 wherein said depression comprises the full thickness of said edge.
  • 6. A connector according to claim 4 wherein said contact edge is castellated, a plurality of successive depressions being provided on said edge.
  • 7. A connector according to claim 5 wherein said contact edge is castellated, a plurality of successive depressions being provided on said edge.
  • 8. A card edge connector comprising a housing having a slot adapted to receive the edge of a card having surface contacts, and opposed resilient terminals within said slot and adapted to grip said surface contacts, said connector further including a short circuit preventing member of electrically insulating material, said preventing member being movable from an advanced position between said opposed terminals to a retreated position rearward of said opposite terminals, and further including a support member having a card edge connector thereon, said support member and said housing being movable together and apart on an insertion axis, said support member and said preventing member having mutually engagable abutments whereby said preventing member is entrained for movement with said support member along said insertion axis between predetermined limits.
  • 9. A connector according to claim 8 wherein said predetermined limits comprise abutment of said support member and housing when said preventing member is in the retreated position, and abutment of said preventing member and housing in the advanced condition.
  • 10. A connector according to claim 8 wherein said mutually engageable abutments comprise a resilient leg of said preventing member and a protrusion of said support member.
  • 11. A connector according to claim 9 wherein said mutually engageable abutments comprise a resilient leg of said preventing member and a protrusion of said support member.
Priority Claims (3)
Number Date Country Kind
2000-401594 Dec 2000 JP
2001-001766 Jan 2001 JP
2001-078305 Mar 2001 JP
US Referenced Citations (2)
Number Name Date Kind
4815895 Purssey et al. Mar 1989 A
5160275 Nakamura et al. Nov 1992 A
Foreign Referenced Citations (1)
Number Date Country
35354 Aug 1984 EP