Connector with locking members

Information

  • Patent Grant
  • 6290521
  • Patent Number
    6,290,521
  • Date Filed
    Monday, April 10, 2000
    24 years ago
  • Date Issued
    Tuesday, September 18, 2001
    23 years ago
Abstract
A connector for electrical terminals includes a housing that has a plurality of cavities, a plurality of respective resiliently deformable locking members, and a plurality of respective terminals. Each terminal is inserted in a respective cavity and has (a) a partially inserted position in which the terminal bears on the respective locking member to deform the locking member so that the locking member is raised with respect to a peripheral surface of the housing, and (b) a fully inserted position in which the locking member snap-fits to the terminal thereby locking the terminal in said cavity. The connector further includes a bus bar holder having a sleeve which accommodates a plurality of bus bar tab pieces. The sleeve is push-fitted over the peripheral surface of the housing to install the bus bar holder to the housing and to contact the tab pieces to the terminals, whereby the terminals are electrically connected to each other. Each locking member has an end surface portion which is adapted so that when, on push-fitting of the sleeve, a terminal is in the partially inserted position with the respective locking member raised with respect to the peripheral surface of the housing, the sleeve bears on the end surface portion to prevent installation of the bus bar holder.
Description




BACKGROUND OF THE INVENTION




1. Field of Invention




The present invention relates to a connector, particularly a connector for use in the wiring of a vehicle such as an automobile.




2. Description of Related Art




A connector disclosed in Japanese Patent Application Laid-Open No. 9-213436 is described below. The connector has a housing into which a plurality of terminals are inserted from a rear portion thereof and a bus bar holder in which a holding member holds a plurality of bus bars each of which has a tab piece projecting from a side edge of a belt-shaped carrier. The bus bar holder is inserted into an opening at the front surface of the housing to connect the tab pieces with the terminals. In this manner, the terminal fittings are electrically connected to each other.




It is also known to lock the terminals into a position in the housing with a plurality of respective locking lances. Theses lances may project outwardly from the housing if the terminals are not fully inserted.




The tab pieces project from the holding member of the bus bar holder and are externally exposed. Therefore, when the bus bar holder is packed in a bag or a box for delivery, or when it is installed to the housing, other bus bar holders may catch on the tab pieces. Thus, there is a risk that the tab pieces can be deformed or damaged.




To prevent such risk, it is known to use a bus bar holder having a protective cylindrical sleeve which accommodates the tab pieces. This construction has an advantage of helping to prevent the tab pieces from being deformed or broken.




Also, with this arrangement the bus bar holder is capable of detecting incomplete insertion of the terminals in the connector housing. When the terminals are fully inserted into the connector housing, the sleeve can be installed onto the housing without interfering with the locking members which hold the terminals in place. On the other hand, when any of terminals is not properly inserted into the connector housing, the respective locking member projects from the peripheral surface of the housing and collides with the end surface of the sleeve on installation. That is, the proper or improper insertion of the terminals can be detected by whether the sleeve interferes with the locking members.




However, when a projecting lance collides with the cylindrical sleeve, the lance may flex excessively, possibly breaking or damaging the lance.




SUMMARY OF THE INVENTION




It is therefore an object of the present invention to prevent a locking member or lance from flexing excessively when a bus bar holder is installed on a connector housing and the respective terminal is not properly inserted.




According to the present invention there is provided a connector for electrical terminals. The connector has a housing with a peripheral surface, a plurality of cavities, a plurality of resiliently deformable locking members, and a plurality of terminals. Each terminal is inserted in a respective cavity and has (a) a partially inserted position in which the terminal bears on the respective locking member to deform the locking member so that the locking member is raised with respect to a peripheral surface of the housing, and (b) a fully inserted position in which the locking member snap-fits to the terminal thereby locking the terminal in the cavity.




The connector also has at least one bus bar holder with a sleeve and a plurality of bus bar tab pieces which are accommodated in the sleeve. The sleeve is push-fitted over the peripheral surface of the housing to install said bus bar holder to the housing and to contact the said tab pieces to the terminals. In this way the terminals are electrically connected to each other.




Each locking member has an end surface portion which is inclined with respect to the push-fit direction of the sleeve. Therefore, when, on push-fitting of the sleeve, a terminal is in its partially inserted position with the respective locking member raised with respect to peripheral surface, the sleeve bears on the respective first end surface portion to urge the locking member toward the terminal. This prevents excess deformation of the locking member from occurring.




Each of the locking member may also have a second end surface portion which faces the first end surface portion and, with respect to the first end surface portion, is oppositely inclined with respect to the push-fit direction of the sleeve. In this way, when, on push-fitting of the sleeve, each terminal is in its partially inserted position with the respective locking member raised with respect to the peripheral surface, the sleeve also bears on the second surface portion to urge the locking member away from the terminal.




The first and second end surface portions may, for example, define a V-shaped recess in the respective locking members.




When the sleeve of the bus bar holder contacts both the first and the second end surface portions of a locking member, the locking member experiences opposing and balance forces on its end surface portions. These forces prevent it from being displaced either away from or toward the terminal. Thus the installation of the bus bar holder on the housing is prevented. That is, even though the bus bar holder is urged strongly against the locking member, the locking member is prevented from being forcibly displaced in a direction which would remove its elastic deformation. Therefore, the locking member is prevented from being pressed against the terminal with an excessive force and possibly being damaged.




Preferably, the angle of inclination of the first end surface portion with respect to the push-fit direction of the sleeve is smaller than the angle of inclination of the second end surface portion with respect to the push-fit direction when the sleeve bears on both the first and second end surface portions.




With this arrangement, the force applied to a locking member by the sleeve in the direction which would remove its elastic deformation (i.e. toward the terminal) is greater than the force applied in the direction which would increase its elastic deformation (i.e. away from the terminal). Accordingly, it is possible to avoid excess flexing and deformation of the locking member.











BRIEF DESCRIPTION OF THE DRAWINGS




Preferred embodiments of this invention will be described in detail by way of non-limitative example with reference to the following drawings, in which:





FIG. 1

is a perspective view of a housing of a connector according to the invention;





FIG. 2

is a partly cut-away perspective view of bus bar holders that engage the housing, seal member and seal holder of

FIG. 1

;





FIG. 3

is a perspective view of a cap that covers the housing of FIG.


1


and the bus bar holders of

FIG. 2

;





FIG. 4

is a sectional view of the connector in an engagement state on plane I—I of

FIG. 1

, plane II—II of FIG.


2


and plane III—III of

FIG. 3

;





FIG. 5

is a sectional view on plane I—I of

FIG. 1

, showing a sealing member and a seal holder installed on the housing;





FIG. 6

is a sectional view on plane II—II of

FIG. 2

;





FIG. 7

is a sectional view on plane III—III of

FIG. 3

;





FIG. 8

is an enlargement of a part of the sectional view of

FIG. 4

, showing a terminal fully inserted into the housing;





FIG. 9

is the same view as

FIG. 8

except that the terminal is partially inserted into the housing;





FIG. 10

is the same view as

FIG. 9

except that a locking lance of the housing is further deformed by a sleeve of the bus bar holder;





FIG. 11

is a partly cut-away plan view of the housing;





FIG. 12

is a rear view of the sealing member; and





FIG. 13

is a rear view of the seal holder.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




A connector embodying the present invention is described in conjunction with

FIGS. 1

to


13


. The connector electrically connects a plurality of terminals


20


in a predetermined connection pattern with a bus bar


55


and includes a housing


10


, a plurality of the terminals


20


, a sealing member


30


, a seal holder


40


, two bus bar units


50


, and a cap


60


.




The housing


10


is made of a synthetic resinous material. As shown in

FIGS. 1 and 5

, the housing


10


may have cavities


11


arranged in upper and lower rows and extending through the housing


10


in a front-to-rear direction. In each of the upper and lower rows, the cavities


11


may be arranged widthwise at regular intervals. The front half regions of the upper-row cavities


11


and the lower-row cavities


11


are open at the upper and lower surfaces of the housing


10


, respectively. In each open portion, locking members, such as locking lances


12


, project forward in a cantilever manner. Between the upper and lower rows of the cavities


11


there is formed a wide recess


13


for allowing the peripheral walls of the bus bar units


50


, as described below, to penetrate. An upper surface wall and a lower surface wall of the recess


13


are partly cut away to allow communication with the cavities


11


.




The locking lances


12


retain and prevent the removal of the terminals


20


inserted into the cavities


11


. In cooperation with a cylindrical portion


53


of the bus bar unit


50


shown in

FIGS. 8-10

, locking the lances are also used for detecting the degree of insertion of the terminals


20


. The locking lances


12


can be outwardly elastically displaced relative to an outer surface


10


A of the housing


10


. As shown in

FIG. 8

, before a terminal


20


is inserted into a cavity


11


and after the terminal


20


is fully inserted therein, a corresponding locking lance


12


is undeformed, and an outer surface


12


A of the locking lance


12


is flush with the outer surface


10


A of the housing


10


. In this state, when the terminals


20


are fully inserted, a removal prevention projection


12


B formed at a front end of each locking lance


12


is engaged in a locking hole


24


of the terminal


20


, thus preventing removal of each terminal


20


. However, as shown in

FIG. 9

, when any of the terminals


20


are not fully inserted, the removal prevention projection


12


B interferes with the outer surface of a mating portion


21


of the terminal


20


. As a result, as described in

FIG. 10

, the locking lance


12


is elastically displaced such that its outer surface


12


A is located outwardly from the surface


10


A of the housing


10


. Therefore, when a bus bar unit


50


is installed on the housing


10


, the cylindrical portion


53


of the bus bar unit


50


collides with the front end of the locking lance


12


. This prevents the bus bar unit


50


from being installed on the housing


10


.




At the front-end surface of each locking lance


12


, there is formed an excess flexure prevention surface


12


C that prevents the locking lance


12


from flexing excessively beyond the limit of its elasticity, when the cylindrical portion


53


collides with the front end of the locking lance


12


. At the front-end surface of each locking lance


12


, there is also formed a balancing surface


12


D inclining in a direction opposite to the direction of inclination of the excess-flexure prevention surface


12


C. For example, in a side view, the front-end surface of the locking lance


12


may be recessed in the shape of a “V”, as shown in

FIGS. 8-10

. The inward side, i.e., the terminal side, of the front-end surface of the locking lance


12


is the excess-flexure prevention surface


12


C and the outer side of the front-end surface is the balancing surface


12


D.




While the surfaces


12


C and


12


D form a “V” shape in

FIGS. 8-10

, it will be appreciated that other shapes are possible. For example, the surfaces


12


C and


12


D may form a curved “U” shape, rather than being linear surfaces that form a “V”. Additionally, rather than two linear surfaces, one or more of the surfaces may be curved, and/or more than two surfaces may be provided at the end of each locking lance


12


.




While the locking lance


12


is elastically displaced within its elastic limit, an end surface of the cylindrical portion


53


collides with the excess-flexure prevention surface


12


C when each bus bar unit


50


is installed on the housing


10


. The excess-flexure prevention surface


12


C is so inclined that the excess-flexure prevention surface


12


C stops and reduces excess elastic deformation of the locking lance


12


, as best shown in FIG.


10


.




While the locking lance


12


is elastically displaced within its elastic limit, the cylindrical portion


53


is also capable of colliding with the balancing surface


12


D, when each bus bar unit


50


is installed on the housing


10


. The balancing surface


12


D is inclined so that the locking lance


12


is then urged in a direction in which the elastic displacement of the locking lance


12


increases (upward in

FIGS. 8

to


10


). Ultimately the cylindrical portion


53


contacts both the excess-flexure prevention surface


12


C and the balancing surface


12


D, as shown in FIG.


10


. Comparing the relative inclinations of the excess-flexure prevention surface


12


C and the balancing surface


12


D when both surfaces are in contact with the cylindrical portion


53


, as shown in

FIG. 10

, the acute angle α between the direction of insertion of the cylindrical portion


53


and the excess-flexure prevention surface


12


C is smaller than the angle β between the insertion direction the cylindrical portion


53


and the balancing surface


12


D.




Each terminal


20


is made of a metal plate material punched into a predetermined configuration. As shown in

FIG. 1

, the front half part of the terminals


20


may be formed as a square pillar-shaped mating portion


21


that is open forward and rearward. The rear half of the terminals


20


is formed as an electric wire connection portion


22


that may be crimped to the core of an electric wire


25


.




As shown in

FIG. 4

, a resilient contact piece


23


that contacts a connection piece


57


of a bus bar


55


is formed inside the mating portion


21


. A locking hole


24


which the locking lance


12


of the housing


10


engages is formed on a peripheral wall of the mating portion


21


. The terminals


20


are inserted into the cavities


11


of the housing


10


by passing through the sealing member


30


and the seal holder


40


at the rear of the housing


10


. Immediately before the terminals


20


reach the fully inserted position, the locking lances


12


interfere with the peripheral surface of the mating portions


21


. Therefore, the locking lances


12


flex elastically outward from the housing


10


. When the terminals


20


reach the fully inserted position, the locking lances


12


are elastically restored to the original state and are engaged in the locking holes


24


, thus preventing the terminals


20


from being removed from the cavities


11


. The orientation of the terminals in the upper row of cavities


11


may be reversed relative to that of the terminals in the lower cavity row.




The sealing member


30


is made of rubber, oval-shaped, and thick. As shown in

FIG. 5

, the sealing member


30


is installed on the housing


10


and is sandwiched between the rear end surface of the housing


10


and the front end surface of the seal holder


40


. The construction of the sealing member


30


with the housing


10


and the seal holder


40


is described in more detailed below with reference to

FIGS. 11-13

. A plurality of sealing holes


31


opened through the sealing member


30


is formed coincident with the cavities


11


of the housing


10


. Each sealing hole


31


may be circular, for example. A lip portions


31


A may have a corrugated shape that includes, for example, three convexities. The convexities are circumferentially formed on the inner peripheral surface of each sealing hole


31


. The inner diameter of the lip portion


31


A is smaller than the outer diameter of the coating of the wire


25


. When the wire


25


is in the sealing hole


31


, the lip portion


31


A contacts the peripheral surface of the wire


25


elastically, thus sealing around the wire


25


. Furthermore, as shown in

FIG. 12

, the sealing member


30


includes fit-in holes


32


and


33


through which holding projections


14


and deformation prevention projections


15


pass, respectively.




As shown in

FIG. 11

, the holding projections


14


include a base portion


14


A and a locking portion


14


B. As the base portions


14


A pass through the fit-in holes


32


, the locking portions


14


B enter removal prevention holes


42


and engage with stepped receiving portions


42


A, preventing the housing


10


, the sealing member


30


and the seal holder


40


from being separated. The deformation prevention projections


15


also pass through the fit-in holes


33


and enter deformation prevention holes


43


. The deformation prevention projections


15


prevent deformation of the sealing member


30


.




The inner diameters of the fit-in holes


32


and


33


are smaller than the holding projections


14


and deformation prevention projections


15


, respectively. Thus, when the holding projections


14


and the deformation prevention projections


15


pass the fit in holes


32


and


33


, respectively, the holding projections


14


and the deformation prevention projections


15


contact fit-in holes


32


and


33


with elasticity, sealing around the holding projections


14


and deformation prevention projections


15


.




The peripheral edge of the sealing member


30


is formed as a corrugated sealing edge. A lip portion


34


has, for example, three convexities approximately semi-circular in section and extending circumferentially around the sealing member


30


. The lip portion


34


contacts the inner peripheral surface of the cap


60


elastically, thus sealing between the sealing member


30


and the cap


60


as shown in FIG.


4


.




The seal holder


40


is made of a relatively rigid synthetic resin material. Similarly to the sealing member


30


, the seal holder


40


may be oval-shaped and thick as shown in FIG.


1


. The lip portion


34


formed on the periphery of the sealing member


30


is slightly larger than the periphery of the seal holder


40


. A plurality of terminal insertion openings


41


extend through the seal holder


40


in correspondence to the cavities


11


and the sealing holes


31


. Each terminal


20


is inserted into a respective cavity


11


through a respective terminal insertion opening


41


.




As shown in FIG.


1


and

FIG. 4

, locking projections


44


are formed at each end of upper and lower surfaces of the seal holder


40


. The locking projections


44


engage the cap


60


, thus hindering the cap


60


from being easily removed from the housing


10


, the sealing member


30


, and the seal holder


40


. An index projection


45


is formed in each circular arc-shaped region located at right and left ends of the peripheral surface of the seal holder


40


. Each of the index projections


45


is formed such that the inward side thereof is on a level higher than that of the outward side thereof. The index projections


45


serve as an index for checking the upper and lower sides of the housing


10


when the terminal fixtures


20


are inserted into the cavities


11


and when the housing


10


is inserted into the cap


60


.




As shown in

FIGS. 2

,


4


and


6


each bus bar unit


50


is composed of a holding member


51


made of a relatively rigid synthetic resin material and a metal bus bar


55


that is integrated with the holding member


51


by insert molding. The holding member


51


has a wide sheet-shaped holding portion


52


and a flat cylindrical portion


53


projecting from the sheet-shaped holding portion


52


. The bus bar


55


includes a plurality of connection pieces


57


projecting in parallel with each other, each in the shape of a cantilever, from an edge of a belt-shaped carrier


56


. The bus bar


55


is held with the carrier


56


disposed along the sheet-shaped holding portion


52


and with connection pieces


57


facing the cylindrical portion


53


. Punched holes


54


are formed on the sheet-shaped holding portion


52


in correspondence to the gap between adjacent connection pieces


57


projecting from the carrier


56


. In the process of producing the bus bar units


50


, a portion of the carrier


56


facing each punched hole


54


is punched with a punch and die in correspondence to a predetermined connection pattern. As a result, the carrier


56


is divided (not shown) into a plurality of bus bars


55


. One bus bar


55


has at least three connection pieces


57


. A plurality of terminals


20


are connected by each bus bar


55


through the connection pieces


57


.




Each bus bar unit


50


is installed on the housing


10


in a direction forward therefrom such that the cylindrical portion


53


covers the upper-row cavities


11


or the lower-row cavities


11


. When each bus bar unit


50


has been installed on the housing


10


, the connection pieces


57


are connected with the terminals


20


. Connection patterns can be discriminated from each other by, for example, changing the color of the holding member


51


of the bus bar unit


50


. The upper part of the holding member


51


and the lower part thereof are not symmetrical. Thus, the correct bus bar unit


50


can be installed on the housing


10


in a correct direction, and a group of the terminals


20


can be connected in a correct pattern by checking colors and directions of the holding members


51


.




As shown in

FIG. 2

, guide grooves


58


extend longitudinally and are formed at each of right and left widthwise edges of the cylindrical portion


53


. As shown in

FIG. 1

, front and rear locking projections


17


and


18


correspond positionally to the guide groove


58


and are formed on the housing


10


. Each bus bar unit


50


is brought to a temporary locking position with the locking projections


18


locked in the guide grooves


58


. In this state, the bus bar unit


50


is held at a temporary locking position. In this state, each connection piece


57


is placed at a retracted position at which the connection piece


57


is not in contact with each terminal


20


, thus preventing generation of resistance at the time of insertion of the terminals


20


. The bus bar unit


50


is then brought to the final installation position by locking the front and rear ends of the guide groove


58


by the locking projections


17


and


18


, respectively. In this state, the front and rear ends of the guide groove


58


sandwich the locking projections


17


and


18


.




Each bus bar unit


50


can be used to detect the inserted state of the terminals


20


. As shown in

FIG. 8

, the cylindrical portion


53


is installed on the housing


10


by sliding it along the surface


10


A of the housing


10


. An inclined surface


53


A is formed on the front-end surface of the cylindrical portion


53


such that the outer side thereof extends further than the inner side (housing side) thereof. The inner-side edge of the inclined surface


53


A is a prevention edge


53


B that contacts the excess-flexure prevention surface


12


C of the locking lances


12


. The outer-side edge of the inclined surface


53


A is a balancing edge


53


C which contacts the balancing surface


12


D of the locking lances


12


. When the bus bar unit


50


has been fully inserted to the housing


10


, the front end of the cylindrical portion


53


covers the outer surface of the front portion of the locking lances


12


.




A description of the cap


60


is given with reference to

FIGS. 3 and 7

. The cap


60


is made of a relatively rigid synthetic resin material. As shown in

FIG. 3

, the cap


60


is oval-shaped in a front view and has a closed bottom. Locking holes


61


to which the locking projections


44


of the seal holder


40


, shown in

FIG. 1

, lock are formed at an edge of an opening of the cap


60


. The cap


60


is locked in the installed state by the engagement between the locking projections


44


and the locking holes


61


. Relief portions


62


project outwardly and are formed on the edge of the opening of the cap


60


to prevent the cap


60


from interfering with the index projections


45


of the seal holder


40


. As shown in

FIG. 7

, a region of the inner peripheral surface of the cap


60


near the edge of the opening is formed as a sealing surface


63


with which the lip portion


34


formed on the peripheral edge of the sealing member


30


contacts elastically (see FIG.


4


).




The connector assembly procedure is as follows:




Initially, the sealing member


30


is sandwiched between the seal holder


40


and the housing


10


. Then, the projections


14


formed on the housing


10


are passed through the sealing member


30


, and locking portions


14


B of the projections


14


are locked to the seal holder


40


. This locks the seal member


30


to the housing


10


, and the removal of the seal holder


40


is prevented. Then, terminals


20


are inserted through the terminal insertion openings


41


and the sealing holes


31


into respective cavities


11


. Thereafter, each bus bar unit


50


is installed at a temporary locking position on the housing


10


, and the bus bar unit


50


is placed on an assembling apparatus (not shown). Then, each bus bar unit


50


is pressed to a normal installation portion from the temporary locking position. As a result, the terminals


20


are connected in a predetermined pattern. When the bus bar units


50


are in the normal installing position, the cap


60


is installed on the housing


10


in such a manner that the cap


60


covers the housing


10


and the bus bar unit


50


as shown in FIG.


4


.




The lip portions


34


formed on the periphery of the sealing member


30


prevent water from penetrating into the cap


60


between the inner periphery of the cap


60


and the periphery of the sealing member


30


. Further, the lip portions


31


A of the sealing holes


31


contact the periphery of the wires


25


closely, the inner periphery of each fit-in hole


32


contacts the periphery of the corresponding holding projection


14


, and the inner periphery of the fit-in hole


33


contacts the periphery of the deformation prevention projection


15


. Therefore, water can be prevented from penetrating into the sealing member


30


from outside.




On installation of each bus bar unit


50


on the housing


10


when all the terminals


20


are fully inserted into their respective cavities


11


, each locking lance


12


is undeformed so that its outer surface


12


A is flush with the outer surface


10


A of the housing


10


. Accordingly, when the cylindrical portion


53


slides over the outer surface


10


A of the housing


10


during bus bar unit installation, the cylindrical portion


53


does not interfere with the locking lances


12


. Thus, each bus bar unit


50


can be installed on the housing securely. When each bus bar unit


50


has been installed on the housing


10


in the normal state, the cylindrical portion


53


faces the locking lances


12


in such a manner that the inner surface of the cylindrical portion


53


holds downward on the outer surfaces


12


A of the locking lances


12


. Thus, the locking lances


12


are prevented from being elastically displaced in a direction which would move them away from the terminals


20


(see FIG.


8


).




On the other hand, if there is any terminal


20


inserted into the cavity


11


incompletely, the removal prevention projection


12


B interferes with the outer surface of the mating portion


21


of the terminal


20


. Thus, the locking lance


12


is elastically displaced outward and projects outward from the outer surface


10


A of the housing


10


. During installation of each bus bar unit


50


on the housing


10


, the inclined surface


53


A that is formed at the front end of the cylindrical portion


53


then contacts the outer-side edge of the locking lance


12


. As a result, the installation operator notices that the installation resistance is suddenly increased. In this manner, the operator can detect that a terminal is in the incomplete insertion state (see FIG.


9


).




The operator suspends the installation operation with the connector in the state shown in FIG.


9


and resumes the installation operation after inserting the terminal


20


into the normal position of the cavity


11


. However, it may happen that the operator continues to perform the installing operation without noticing a sudden increase in installation resistance. The locking lance


12


shown in

FIG. 9

is then displaced upward by a force acting in the bus bar unit installation direction, the balancing edge


53


C of the cylindrical portion


53


contacting and transmitting the force to the balancing inclined surface


12


D. If the locking lance


12


were to flex upward further and exceed the limit of its elasticity, it would not be restorable to the undeformed state shown in FIG.


8


. However, this is prevented because when the locking lance


12


flexes further, to a position still within its elastic limit, the prevention edge


53


B of the cylindrical portion


53


contacts the excess-flexure prevention surface


12


C (see FIG.


10


). The excess-flexure prevention surface


12


C has an inclination such that the locking lance


12


is urged in the opposite (elasticity-restoring) direction by the collision force of the cylindrical portion


53


applied to the excess-flexure prevention surface


12


C. Thus, the locking lance


12


is prevented from being elastically displaced further.




As described above, as a mechanism to prevent the locking lances


12


from flexing excessively beyond the limit of their elasticity, the cylindrical portion


53


is pressed against the excess-flexure prevention surface


12


C. Thus, it is also unnecessary to provide the housing


10


with a wall for preventing excess deformation of the locking lance


12


, which makes it possible to reduce the width of the housing


10


.




When the cylindrical portion


53


of each bus bar unit


50


contacts both the excess-flexure prevention surface


12


C and the balancing surface


12


D, as shown in

FIG. 10

, the locking lances


12


are prevented from being displaced in either direction. Thus installation of the bus bar unit


50


on the housing


10


is prevented. That is, even if the bus bar unit


50


is pressed strongly against the lances


12


, the lances


12


are prevented from being forcibly displaced in the elasticity-restoring direction. In particular, when the cylindrical portion


53


contacts the balancing surfaces


12


D, the locking lances


12


are spaced from the terminals


20


. Therefore, even though the locking lance


12


may be displaced slightly in the elasticity-restoring direction, there is no possibility that the locking lance


12


is urged excessively against the terminals


20


.




The acute angle α formed between the insertion direction of the cylindrical portion


53


and the excess-flexure prevention surface


12


C is smaller than the angle β which formed between the insertion direction and the balancing surface


12


D. Thus, when a force acting in the installation direction is initially applied to the locking lances


12


by the cylindrical portion


53


, the resultant force that is applied to the locking lances


12


in the downward (elasticity-restoring) direction (i.e., torward the cavity) is greater than the resultant force that is applied in the upward (increased elastic displacement) direction (i.e., away from the cavity). Accordingly, it is possible to prevent excess deformation of the locking lances


12


.




The inclined surface


53


A of the cylindrical portion


53


may be inclined with respect to the bus bar unit-installation direction, as shown in the drawings. Therefore, even if the locking lances


12


may be slightly raised with respect to the outer surface


10


A of the housing


10


when the terminals


20


are fully inserted, the lances


12


are not snagged by prevention edge


53


B of the cylindrical portion


53


during installation of each bus bar unit


50


into the housing


10


.




The present invention is not limited to the embodiments described, but may be varied, for example, as described below.




(1) In the above description, the front end surface of the cylindrical portion


53


of the bus bar unit


50


is angled and the edges of the surface contact the excess-flexure prevention surface


12


C and the balancing surface


12


D. However, within the present invention, the front end surface of the cylindrical portion


53


may be V-shaped so that the end surface corresponds to and contacts the excess-flexure prevention surface


12


C and the balancing surface


12


D.




(2) In the above description, the acute angle α between the insertion direction of the cylindrical portion


53


and the excess-flexure prevention inclined surface


12


C is smaller than the angle β between the insertion direction and the balancing inclined surface


12


D. However, within the present invention, although less desirably, angle α may be larger than angle β or angle α may be equal to angle β.




(3) In the above description, the balancing surface


12


D is in addition to the excess-flexure prevention surface. However, within the present invention, it is possible to form only the excess-flexure prevention inclined surface.




(4) In the above description, the end surface of the cylindrical portion


53


is angled relative to the insertion direction of the cylindrical portion. However, according to the present invention, the end surface of the cylindrical portion


53


may be perpendicular to the insertion direction, or may be angled in the opposite direction.




(5) In the above description, the cylindrical portion


53


initially contacts the outer-side edge of the locking lance


12


when a terminal is partially inserted. However, within the present invention, the cylindrical portion


53


may contact an inclined surface of the locking lance


12


initially. In this case, the locking lance


12


first contacts the balancing surface


12


C, and thereafter the excess-flexure prevention surface


12


D after slight displacement of the locking lance


12


. Alternatively the cylindrical portion


53


may contact both inclined surfaces.




(6) In the above description, a connector of waterproof type has been described. However, the present invention is also applicable to connectors of non waterproof type.




Although the invention has been described above in relation to particular embodiments, many variations are possible within the spirit and scope of the invention herein described, as will be appreciated by those who are skilled in the art, once given this disclosure.



Claims
  • 1. A connector comprising:a housing having an outer peripheral surface, a plurality of cavities, a plurality of resiliently deformable locking members, and a plurality of terminals, each of said terminals being inserted in a respective one of said cavities and having (a) a partially inserted position in which said terminal bears on said locking member to deform said locking member so that said locking member is deflected outward of said outer peripheral surface, and (b) a fully inserted position in which said locking member snap-fits to said terminal thereby locking said terminal in said cavity; and a bus bar holder having a sleeve and a plurality of bus bar tab pieces said bus bar tab pieces being accommodated in said sleeve, and said sleeve being push-fitted onto said peripheral surface of said housing to install said bus bar holder to said housing and to contact said tab pieces to said terminals, whereby said terminals are electrically connected to each other; wherein each locking member has a first end surface portion which is inclined with respect to a push-fit direction of said sleeve, whereby when one or more of said terminals are in said partially inserted position with one or more respective said locking members deflected outward of said outer peripheral surface when push-fitting said sleeve onto said housing, said sleeve bears on said end surface portion to urge the one or more said locking members toward said terminal thereby preventing excess deformation of the one or more said locking members.
  • 2. The connector according to claim 1, wherein each said locking member has a second end surface portion which faces said first end surface portion and, with respect to said first end surface portion, is oppositely inclined with respect to the push-fit direction of said sleeve, whereby when, on push-fitting of said sleeve onto said housing, each of said terminal is in said partially inserted position with the respective said locking member deflected outward of said outer peripheral surface, said sleeve bears on said second surface portion to urge said locking member away from said terminal.
  • 3. The connector according to claim 2, wherein said first and second end surface portions define a V-shaped recess in said locking member.
  • 4. The connector according to claim 2, wherein said first and second end surface portions are formed so that when, on push-fitting of said sleeve onto said housing, said terminal is in said partially inserted position with each of said locking member deflected outward of said outer peripheral surface, said sleeve bears on both said first and said second end surface portions.
  • 5. The connector according to claim 4, wherein said first and said second end surface portions are formed so that when said sleeve bears on both said first and said second end surface portions, an angle of inclination of said first end surface portion with respect to said push-fit direction is smaller than the angle of inclination of said second end surface portion with respect to said push-fit direction.
Priority Claims (3)
Number Date Country Kind
11-105919 Apr 1999 JP
11-105920 Apr 1999 JP
11-118479 Apr 1999 JP
US Referenced Citations (11)
Number Name Date Kind
5000699 Nadin Mar 1991
5201667 Endo et al. Apr 1993
5462450 Kodama Oct 1995
5525077 Badaroux Jun 1996
5554052 Saijo et al. Sep 1996
5655928 Akeda Aug 1997
5746624 Ohsumi et al. May 1998
5769650 Aoyama et al. Jun 1998
5890932 Muta Apr 1999
5944557 Fukuda Aug 1999
6068512 Sugie May 2000
Foreign Referenced Citations (3)
Number Date Country
U-2-61082 May 1990 JP
U-4-42082 Apr 1992 JP
A-9-213436 Aug 1997 JP