Patent Publication Number: US-9899772-B2

Title: Electric connector

Description:
The present invention relates to an electric connector comprising a first connector element and a second connector element complementary to the first, these two connector elements being provided to fit in one another. For example, such a connector can be used to electrically connect an electric vehicle to a power source, in order to recharge the batteries of this vehicle. 
     BACKGROUND OF THE INVENTION 
     One connector that may be appropriate for this application is known from EP-A-2,752,946. In this connector, during the fitting or coupling of the elements of the connector, their bodies are indexed around a longitudinal axis, in order to align each prong with a corresponding contact. Next, pins are immobilized by engagement in corresponding locking slots, withdrawal of a safety tab, and elastic return of this safety tab to the position blocking the pins in the slots. To allow a pin to penetrate the corresponding locking slot automatically, it is necessary for the locking ring to be oriented relative to the body around which is mounted to align itself with this locking pin. This is possible owing to a largely flared entry bevel of the locking slot, this bevel covering the angular travel range of the locking ring. This connector is globally satisfactory. However, the presence of the bevel increases the axial length of the locking ring, and therefore the axial length of the electric connector thus formed. Yet in some applications, it is necessary to provide an electric connector with a reduced axial bulk. 
     Comparable problems arise with the equipment known from DE-A-196 45 730 and U.S. Pat. No. 4,547,032, which lacks a locking ring movable between a forward position and a withdrawn position. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention more particularly aims to resolve these problems by proposing a new electric connector in which a locking pin can effectively be placed in a locking slot, without having to use an entry bevel. 
     To that end, the invention relates to an electric connector comprising a first connector element and a second connector element complementary to the first connector element, these two connector elements being provided to fit in one another along a fitting axis. The first connector element comprises a first body that is secured to at least one locking pin and that bears at least one first prong or first contact. The first connector element also comprises at least one first indexing member secured to the first body. The second connector element comprises a second body that supports at least one second contact or second pin complementary to the first prong or first contact, as well as a locking ring mounted around the second body while being axially immobilized, along the fitting axis, and rotatable, around this axis, relative to the second body. This locking ring is provided with at least one locking slot, with a mouth and a locking end provided to receive the locking pin in a configuration where the locking pin is axially locked, along the fitting axis, relative to the second body. The second connector element also comprises at least one second indexing member configured to cooperate with the first indexing member, secured to the second body and configured to position the first body angularly relative to the second body around the fitting axis in an indexed configuration that occurs, during the fitting of the first and second connector elements, before the engagement of the locking pin in the locking slot. According to the invention, the second connector element comprises at least one obstacle moving relative to the locking ring between a first position blocking the rotation of the locking ring relative to the second body and a second, released position in which the obstacle does not oppose a rotation of the locking ring around the second body. Furthermore, the second connector element comprises a blocking ring moving, relative to the second body and along the fitting axis, between a first forward position, and at least one second withdrawn position. The second connector element lastly comprises a member for elastically returning the blocking ring toward its first forward position. The obstacle, the locking ring and the second body are configured so that, when the first and second indexing members cooperate and when the obstacle is in its first blocking position, this obstacle blocks the locking ring relative to the second body in a configuration where the mouth of the locking slot is aligned, in a direction parallel to the fitting axis, with the locking pin. Furthermore, the blocking ring is configured so as, during the fitting of the first and second connector elements and when the first and second indexing members cooperate, on the one hand, to be in its first forward position, in which it keeps the obstacle in its first blocking position, before the locking pin is engaged in the locking slot, and on the other hand, to be pushed by a portion of the first connector element, from its first forward position into its second withdrawn position, in which it does not oppose the passage of the obstacle toward its second released position. 
     Owing to the invention, the obstacle provided in the second connector element makes it possible to guarantee appropriate positioning of the or each locking slot relative to the corresponding locking pin(s) upon coupling when the indexing members cooperate. More specifically, the invention makes it possible to guarantee that the or each locking pin is aligned, in a direction parallel to the fitting axis, with the entry of the corresponding locking slot, which makes it possible to do away with the use of an entry bevel. The axial length of the locking ring can thus be reduced, as can the overall axial bulk of the connector. 
     According to advantageous, but optional aspects of the invention, such a connector may incorporate one or more of the following features, considered according to any technically admissible combination:
         The blocking ring is secured in rotation with the locking ring.   The second body comprises at least one concave cavity and the obstacle is engaged in the concave cavity when it is in its first blocking position.   The body also comprises a circumferential peripheral groove that communicates with the concave cavity and that is able to receive the obstacle when it is in its second released position.   The obstacle is movable in a radial orifice of the locking ring and the blocking ring is provided with a first inner radial surface, which, in the uncoupled configuration of the electric connector, surrounds the obstacle and keeps the obstacle in its first blocking position.   The blocking ring is provided with a second inner radial surface, which is cylindrical with a circular base and the radius of which is strictly larger than the radius of the first inner radial surface, which is also cylindrical with a circular base, while the second inner radial surface defines a housing for partially receiving the obstacle when the blocking ring is in its second withdrawn position.   The blocking ring has multiple parts and comprises a front part intended to be in contact with the portion of the first connector element during the fitting of the first and second connector elements and a rear part that is provided with first and second inner radial surfaces.   The blocking ring comprises a release tab that is aligned with the mouth, in a direction parallel to the fitting axis, which is axially movable in the locking slot and which is configured to be pushed by the portion of the first connector element, which is then formed by the locking pin during the fitting of the first and second connector elements, while moving the blocking ring from its first forward position to its second withdrawn position.   During the fitting of the first and second connector elements, the blocking ring reaches its second withdrawn position when the locking pin is completely engaged in the locking slot.   The connector comprises at least three obstacles, preferably six obstacles, distributed around the fitting axis, and each obstacle is formed by a ball.   The second connector element comprises a safety tab stationary in rotation around the fitting axis, and axially movable along this axis, relative to the locking ring between a first stop position, in which it blocks the passage of the locking pin between the locking end of the locking slot and the mouth of the locking slot, and a second released position, in which it allows the passage of the locking pin. A member for elastically returning the safety tab toward its first stop position is also provided.   The safety tab is different from the release tab.   The safety tab is fast with the blocking ring.   The locking slot comprises a front edge and/or a rear edge inclined relative to the fitting axis and relative to a plane perpendicular to the fitting axis and that extends from the mouth to the locking end.   In the fitted configuration of the connector, the blocking ring at least partially covers the locking slot and the locking pin.       

    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The invention will be better understood, and other advantages thereof will appear more clearly, in light of the following description of one embodiment of an electric connector and a recharging installation according to its principle, provided solely as a non-limiting example and done in reference to the appended drawings, in which: 
         FIG. 1  is an axial sectional view of a first element of an electric connector according to the invention, used within a recharging installation also according to the invention; 
         FIG. 2  is an axial sectional view similar to  FIG. 1  for a second element of the connector according to the invention; 
         FIG. 3  is a perspective view of the second connector element shown in section in  FIG. 2 ; 
         FIG. 4  is a cross-sectional view along line IV-IV in  FIG. 2 ; 
         FIG. 5  is a smaller-scale axial sectional view of the male and female elements of the connector during a prior fitting step thereof; 
         FIG. 6  is a partial perspective view of the male and female elements of the connector in the configuration of  FIG. 5 ; 
         FIG. 7  is an axial sectional view similar to  FIG. 5 , when the male and female elements of the connector are in a first fitting step; 
         FIG. 8  is a larger-scale half-sectional view along line VIII-VIII in  FIG. 5 ; 
         FIG. 9  is an outside view of the male and female elements of the connector during a second fitting step; 
         FIG. 10  is a larger-scale sectional view along line X-X in  FIG. 7 ; 
         FIG. 11  is a sectional view similar to  FIG. 5  during a third fitting step; 
         FIG. 12  is an outside view of the connector in the fitted configuration; and 
         FIG. 13  is an axial sectional view similar to  FIGS. 5, 7 and 9  in the fitted configuration. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the aforementioned figures, prongs and contacts are visible. They are normally connected to conductive cables that are not shown, for clarity of the drawing. 
     In the rest of this description, the forward direction of a connector element is defined as the direction oriented in the fitting or coupling direction, i.e., toward the complementary connector element. Conversely, the rear direction of a connector element is defined as the direction opposite the complementary connector element. 
     The female element  100  shown in the uncoupled state in  FIG. 1  belongs to an electric connector R shown in  FIG. 5  and following and that also comprises a male element  200  shown in the uncoupled state in  FIGS. 2 to 4 . 
     The female element  100  has a globally cylindrical structure centered on an axis X 1 . This female element  100  includes an outer body  102  on which three locking pins  104  are fixedly positioned, radially and oriented outward. Each locking pin  104  extends along an axis Y 104  radial to the axis X 1  and comprises a hub  1042  forming a single piece with the body  102 , a roller  1044 , a screw  1046  and a washer  1048 , the screw and the washer being used to keep the rollers  1044  on the hub  1042 , with the possibility of rotation around the axis Y 104 . The three locking pins  104  are positioned angularly equally distributed around the axis X 1 , i.e., with an angular interval of 120° around this axis. 
     In general, at least one locking pin  104  is necessary to lock the connector R. 
     The body  102  of the female element  100  further includes an indexing tooth  106  positioned radially inside the body  102  and in front relative to the locking pins  104 . In other words, the indexing tooth  106  is oriented toward the male element  200  during the fitting or coupling of the elements  100  and  200  of the connector R. Furthermore, the angular orientation of the indexing tooth  106  around the axis X 1  is the same as that of one of the locking pins  104 . 
     Inside the outer body  102 , an insulating inner body  110  is positioned, with a cylindrical shape and also centered on the axis X 1 . This body  110  defines two housings  111  in each of which a power prong  112  is positioned. According to aspects of the invention that are not shown, the body  110  can also contain a ground prong and pilot prongs, as considered in the EP-A-2,752,946. The insulating body  110  bears against an inner shoulder  1022  of the outer body  102  and is kept in position inside this body using a circlip  114 . The insulating body  110  is made stationary in rotation around the axis X 1  in the outer body  102  by cooperation of an axial rib of the insulating body  110  with an axial slot of the outer body  102 . 
     The female connector element  100  is mounted on a body element  500  of a motor vehicle using screws  502  that traverse an outer peripheral collar  1024  of the body  102 , as well as the body  500 . In  FIG. 1 , the screws  502  are shown by their axis lines. In  FIGS. 9 and 12 , the body  500  is omitted for clarity of the drawing. 
     The male element  200 , which is shown in the uncoupled state in  FIGS. 2 to 4 , also belongs to the connector R. It is integrated into a recharging station  600  and connected to a stationary unit  602  of this station by a flexible cable  604 . The parts  600 ,  602  and  604  are shown in mixed lines only in  FIG. 3 . The male element  200  also has a globally cylindrical structure centered on an axis X 2 . The body  202  of the male element includes an indexing slot  206  that extends parallel to the axis X 2  from the front end  2022  of the body  202  where the mouth  2062  of the indexing slot  206  is defined. 
     As in the female element  100 , an inner insulating body  210  is positioned inside the body  202  of the male element  200  and encompasses two power contacts  212  that are complementary to the prongs  112  and each positioned in a housing  211  of the insulating body  210 . The insulating body  210  is kept bearing against an inner shoulder  2024  of the body  202  by a rear ring  203  that is screwed on the rear of the body  202 , with interposition of a sealing point  204  and that tightly receives the flexible cable  604 . The insulating body  210  is made stationary in rotation around the axis X 2  in the outer body  202  by cooperation of an axial rib of the insulating body  210  with an axial slot of the body  202 . 
     A locking ring  216  is mounted rotatably around the body  202 . The locking ring  216  is immobilized in translation, along the axis X 2 , relative to the body  202 . Indeed, the locking ring  216  is axially jammed between an outer shoulder  2026  of the body  202  and the rear ring  203 . A flywheel  218  is secured in rotation and translation with the ring  216 . This flywheel comprises three branches  2182  that connect an inner and rear ring  2184  to an outer and front ring  2186 . The flywheel  218  is immobilized on the locking ring  216  using screws  220 . 
     The locking ring  216  includes three locking slots  222  regularly distributed, at 120° intervals, around the axis X 2  and that each extend between a mouth  2222  cut in the front edge  2162  of the locking ring  216  and a rear end  2224  that forms a locking zone of a pin  104 . The front edge  2162  of the locking ring  216  is positioned behind the front edge  2022  of the body  202 . Between the mouth  2222  and the rear end  2224 , each slot  222  is defined between a front edge  2226  and a rear edge  2228 , these edges being inclined relative to the axis X 2  and relative to a plane perpendicular to the axis X 2 . In particular, the front  2226  and rear  2228  edges are substantially parallel. More specifically, an axis X′ 2  is considered parallel to the axis X 2  and passing through the center of the mouth  2222 . A line D 222  is also considered parallel to the front edge  2226  or the rear edge  2228  of the slot  222  in a plane orthoradial to the axis X 2  passing through the axis X′ 2 . In this orthoradial plane, the axis X′ 2  and the line D 222  define an angle γ 222  between them, taken on the front of the connector element  200 , that is non-zero and strictly less than 90°. In practice, the angle γ 222  is between 30° and 60°, preferably about 45°. It will be noted that the front edge  2226  of the slot  222  is continuous, from the rear end  2224  up to the mouth  2222 . The rear edge  2228  is in turn interrupted to allow two tabs to pass, i.e., a release tab  2407  and a safety tab  2408 , the functions of which are explained below. 
     As more particularly shown by  FIG. 4 , the insulating body  210  defines three housings  211  for power contacts  212  or a ground contact, as well as two housings  213  for pilot contacts not shown in the figures. 
     The male connector element  200  comprises six balls  230 , each housed in a through radial orifice  2164  of the locking ring  216 . The diameter of each ball  230  is larger than the radial thickness of the locking ring  216 , such that, when they are engaged in the orifices  2164 , the balls  230  protrude radially from the ring  216 , either inward toward the axis X 2  or outward away from this axis. The number of balls  230  may be different from six, while being greater than or equal to one. When several balls are used, they are preferably distributed regularly around the axis X 2  owing to appropriate positioning of the orifices  2164 . 
     The body  202  is provided with six identical grooves  2021  that each extend circumferentially over the outer surface of the body  202  and that each end with a cavity or depression  2023 , in the form of a concave spherical cap. Each cavity  2023  is hollowed out more deeply, in a radial direction, in the body  202  than the grooves  2021 . Each cavity  2023  communicates with a groove  2021 . The surface of each cavity  2023  is complementary to the inner radial part of an obstacle  230 . In the configuration of  FIGS. 2 to 4 , each ball  230  is engaged in a cavity  2023 . In this configuration, due to the engagement and maintenance of the balls  230  in the cavities  2023 , the balls  230  secure the locking ring  216  and the body  202  together in rotation, around the axis X 2 . 
     It will be noted that, opposite each cavity  2023 , each groove  2021  is bordered by a boss  2025  that separates it from the cavity  2023  making up the end of the adjacent groove  2021 . 
     The male connector element  200  also comprises a blocking ring  240  that comprises a front part  2402  and a rear part  2404 . These parts  2402  and  2404  are assembled using five screws  2406 , as shown in  FIG. 4 , only one of these screws being shown in  FIG. 7  in light of the cutting planes used. The blocking ring  240  radially surrounds the locking ring  216 , as well as the six balls  230 . The locking ring  240  is axially movable, along the axis X 2 , relative to the locking ring  216  and the body  202 . More specifically, a bearing ring  250  is mounted around the locking ring  216 , this bearing ring being equipped with an inner bevel that rests against an O-ring  252  partially received in an outer peripheral groove of the locking ring  216 . A helical spring  260  is axially inserted between the bearing ring  250  and an inner shoulder  2403  of the front part  2402 . This spring  260  constitutes an element for elastically returning the blocking ring  240  toward the front of the male element  200 . Thus, the bearing ring  250  is kept blocked in translation parallel to the axis X 2 , in a front-rear direction. 
     The rear part  2404  of the blocking ring  240  defines a first cylindrical inner radial surface S 1  with a circular base and centered on the axis X 2 , the radius R 1  of which is substantially equal to the outer radius of the locking ring  216  measured at an outer radial surface  2166 . 
     The rear part  2404  of the blocking ring  240  also defines a second inner radial surface S 2 , which is cylindrical with a circular base like the surface S 1 , but the radius R 2  of which is strictly larger than the radius R 1  and which is offset forward along the axis X 2  relative to the surface S 1 . The inner radial surfaces S 1  and S 2  are connected by an inner frustoconical surface S 3 . In practice, the difference between the radii R 1  and R 2  is greater than or equal to the depth of the cavities  2023  relative to the grooves  2021 . The stepped structure formed by the inner radial surfaces S 1  and S 2  of the blocking ring  240  allows two separate radial positions of the balls  230 , relative to the locking ring  216 , within the orifices  2164 , namely:
         a first blocking position, in which the surface S 1  is axially across from the balls  230 , such that it forces these balls to penetrate the cavities  2023 , which secures the locking ring  216  and the body  202  in rotation,   a second released position, in which the balls  230  can be partially engaged in a volume V 1  defined between the surface S 2  and the outer radial surface of the locking ring  216 , to the point that they can be removed from the cavities  2023  while allowing a relative rotation between the locking ring  216  and the body  202 .       

     The balls  230  therefore constitute an obstacle that makes it possible to block the rotation of the locking ring  216  relative to the body  202 , when necessary, as explained below. The grooves  2021  and the cavities  2023  together constitute housings in which the inner radial parts of the balls  230  are engaged, these inner radial parts having, relative to the body  202  and within these housings, a radial movement at the cavities  2023  and a circumferential movement at the grooves  2021 . 
     The blocking ring  240  also comprises three release tabs  2407  that each extend through a longitudinal housing  2167  arranged in the locking ring  216  and that each emerge in a locking slot  222 . The blocking ring  240  also comprises three safety tabs  2408  each engaged in a longitudinal housing  2168  of the locking ring  216  and that also each emerge in a locking slot  222 . As mentioned above, the release  2407  and safety  2408  tabs interrupt the rear edge  2228  of the slot  222  in which they are engaged. 
     Since the housings  2167  and  2168  are longitudinal, i.e., parallel to the axis X 2 , and in light of the respective dimensions of the tabs  2407  and  2408  and these housings, the blocking ring  240  is secured in rotation, around the axis X 2 , with the locking ring  216 . 
     An O-ring seal  270  is mounted in an outer peripheral groove  2028  of the body  202 , this groove being positioned, along the axis X 2 , past the bottom  2064  of the indexing slot  206  relative to the front end  2022  of the body  202 . 
     The male connector element  200  also comprises a protection ring  280  that is positioned around the front part of the body  202  and that protects the respective mouths  2062  and  2222  of the indexing slot  206  and the locking slots  222  from becoming dirty. To make it possible to view certain parts of the connector R, this protection ring  280  is not shown in  FIGS. 3 and 9 . As shown in  FIG. 12 , the protection ring  280  is secured to the locking ring  216  using screws  282 , only one of which is visible in this figure. 
     The blocking ring  240  is provided with an outer peripheral collar  2405 . 
     The connector R works as follows: 
     In the uncoupled configuration, the female  100  and male  200  elements of the connector are in the configuration of  FIGS. 1 to 4 . In this configuration, the spring  260  pushes the blocking ring  240  toward the front of the connector element  200 , to the point that the tabs  2407  and  2408  protrude in the locking slots  222 . In this configuration, the surface S 1  of the blocking ring  240  is axially aligned with the balls  240 , which are radially maintained by this surface S 1  in a configuration engaged within the cavities  2023 . An inner front edge  2401  of the blocking ring  240  abuts at the front against an outer shoulder  2161  of the locking ring  216 . The position of the cavities  2023  on the outer peripheral surface of the body  202 , on the one hand, as well as the position of the orifices  2164  in the locking ring  216 , on the other hand, are chosen such that in this configuration, the mouth  2222  of one of the locking slots  222  is angularly aligned, around the axis X 2 , with the mouth  2062  of the indexing slot  206 . 
     When the elements  100  and  200  of the connector need to be fitted or coupled, their respective central axes X 1  and X 2  are aligned on a shared fitting axis XR, which is the central axis of the connector R. Next, the indexing members formed by the indexing tooth  106  and the indexing slot  206  are actuated by aligning these members with one another in a direction parallel to the axis XR and engaging the indexing tooth  106  in the indexing slot  206 . The cooperation of the indexing members  106 ,  206  aligns, along the axis XR, each prong  112  supported by the first body  104  with the corresponding contact  212  supported by the second body  204 . The bodies  102  and  202  are then in the indexed configuration. 
     Since the indexing tooth  106  is angularly aligned with one of the pins  104 , while the mouth  2222  of one of the locking slots  222  is angularly aligned with the mouth  2062  of the indexing slot  206  by the blocking of the rotation of the blocking ring  216  by the balls  230 , this pin  104  is automatically aligned with this mouth  2062  along the axis X′ 2 , without it being necessary to use a centering bevel. In particular, the axis X′ 2  is secant with the axis Y 104  of the pin  104 . 
     In other words, in the prior configuration of  FIGS. 5 and 6 , i.e., at the beginning of fitting of the two connector elements  100  and  200  in one another and before the engagement of the pin  104  in the mouth  2062  of the locking slot  222 , the indexing tooth  106  engages in the longitudinal indexing slot  206  and automatically orients the body  102  of the female element  100  relative to the body  202  of the male element  200  around the central axis XR, such that the aforementioned pin  104  is automatically aligned with the mouth  2222  of the aforementioned slot  222 . Furthermore, since the three pins  104  and the three slots  222  are regularly distributed around the axis XR, all of the pins  104  and all of the mouths  2222  of the slots  222  are automatically correctly aligned parallel to the axis XR, relative to one another. 
     The actual fitting of the elements  100  and  200  begins during a first fitting step shown in  FIGS. 7 and 8 . As shown in  FIG. 7 , the inner radial surface of the body  102  then bears on two zones Z 1  and Z 2  of the outer peripheral surface of the body  202  that are axially offset, along the axis XR, from one another, while being positioned on either side of an outer peripheral groove  2027  of the body  202 . 
     From the prior configuration where each pin  104  is aligned on the mouth  2222  of a locking slot  222  and situated outside this slot, the axial movement of the first fitting step of the elements  100  and  200  results in bringing the roller  1044  of each pin  104  into each locking slot  222 , then bearing against the release tab  2407  protruding in the corresponding locking slot  222 . 
     This bearing of the rollers  1044  on the release tabs  2407  and the continued fitting of the elements  100  and  200  result in causing the ring  240  to withdraw against the elastic force exerted by the spring  260 , which axially offsets the surface S 1  relative to the balls  230 , which are then radially across from the surface S 2 . The balls  230  can then move relative to the body  202  from their blocking position to their released position and be partially engaged in the volume V 1 , which is made up of a radial interstice defined between the surface S 2  and the outer radial surface  2166  of the ring  216 . In so doing, the balls  230  can be radially removed from the cavities  2023  to each roll in a groove  2021 . Thus, during fitting, in the configuration of  FIGS. 7 and 8 , the balls  230  have reached a released position in which they do not oppose a rotation of the locking ring  216  around the body  202  for the progression of the pin  104  in the locking slot  222  toward the locking end  2224  and the locking of the locking pin  104  in the locking slot  222 , since they can roll in the grooves  2021 . 
     The passage from the uncoupled configuration to the configuration of  FIGS. 7 and 8  corresponds to a first withdrawal of the blocking ring  240  to an intermediate position where the balls  230  are engaged in the volume V 1  near the surface S 1 . In this configuration of  FIGS. 7 and 8 , the locking ring  216  has not begun to rotate relative to the body  202 . The indexing tooth  106  continues its progression in the indexing slot  206 . 
     As shown in  FIGS. 3, 5 and 9 , the front surface  2407   a  of the release tab  2407 , i.e., the surface that receives the roller  1044  of a pin  104  by bearing, is an axial surface perpendicular to the axis XR, and the axis X′ 2  is secant with the surface  2407   a  such that upon coupling, in the configuration of  FIGS. 7 and 8 , the bearing between a pin  104  and the release tab  2407  is only axial. Furthermore, the surface  2407   a  is aligned along the axis X′ 2  with the mouth  2222 , such that the pin  104  inserted into the mouth  2222  in axial motion comes into contact with the surface  2407   a.    
     By continuing the fitting of the male and female elements in one another, one reaches the configuration of  FIGS. 9 to 11 . In this configuration, the balls  230  are in the released position in the orifices  2164  and are moved in the grooves  2021  while accompanying the rotational movement of the locking ring  216  around the body  202 . In practice, during this step, the locking ring  216  is rotated around the body  202  owing to a torque exerted by the operator on the flywheel  218 , in the direction of arrows F 1  in  FIG. 10 . This rotational movement of the locking ring  216  makes it possible to accompany the progression of the locking pins  104  inside the locking slots  222  toward their respective rear ends  2224 . It should be noted that once the locking pins  104  leave contact with the release tab  2407 , the blocking ring  240  is kept in the intermediate withdrawn position by abutment, under the effect of the spring  260 , of the inner frustoconical surface S 3  of the blocking ring  240  on the balls  230 , which in turn are engaged in the grooves  2021 , offset in the circumferential direction relative to the cavities  2023 . During this movement, the rollers  1044  of the pins  104  come into contact with the safety tabs  2408 , which protrude in the locking slots  2222  and partially obstruct the passage for the pins  104 . As shown in  FIGS. 3 and 9 , each safety tab  2408  is beveled and includes a bowed surface  2408   a  that facilitates a clean bearing of the roller  1044  on the safety tab  2408 . Thus, under the effect of the rotation of the locking ring  216  resulting from the torque exerted by the operator on the flywheel  218 , each pin  104  pushes the adjacent safety tab  2408  toward the rear of the male connector element  200 , which causes a second withdrawal of the blocking ring  240  and frees the passage for this pin, which can reach its locked position at the rear end  2224  of the slot  222 , this end being closed. 
     As shown in  FIG. 11 , from this configuration and for the rest of the fitting, the body  102  covers the sealing gasket  270 , which provides sealing of the connection inside the bodies  102  and  202  when the prongs  112  come into electrical contact with the contacts  212 . This  FIG. 11  shows that, in light of the second withdrawal of the blocking ring  240 , the outer radial parts of the balls  230  are moved within the volume V 1  to reach the front end of the rear part  2404 . The indexing tooth  106  continues its progression in the indexing slot  206 . 
     In the completely fitted or coupled configuration shown in  FIGS. 12 and 13 , each pin  104  has protruded past the safety tab  2408  that extends in the relevant locking slot  222 , such that the spring  260  can send the blocking ring  240  forward again, in a configuration where the latter surrounds and partially covers the locking pins  104  and the locking slots  222 , as well as the interstice between the locking ring and the blocking ring, between the shoulder  2161  and the inner front edge  2401 , which limits the introduction of dirt into these slots and makes it possible to keep as clean as possible an interstice between the locking ring and the blocking ring. 
     Upon comparing  FIGS. 7, 11 and 13 , it will be understood that the blocking ring first withdraws to an intermediate position shown in  FIG. 7 , then to a maximum rear position shown in  FIG. 11 , before returning to the intermediate position shown in  FIG. 13 . In all of these withdrawn positions of the blocking ring  240 , the balls  230  are engaged in the volume V 1  and can roll in the grooves  2021 , such that they do not oppose the rotation of the locking ring  216  relative to the body  202 , in the angular travel offered by the circumferential expanse of the groove  2021  and necessary to lock each pin  104  in its locking slot  222 . 
     When each pin  104  reaches the rear end  2024  of the slot  222  in which it is engaged, it is locked in this end by the safety tab  2408 , which is returned to the slot because the blocking ring  240  is pushed elastically forward by the spring  260  axially bearing against the balls  230 . Thus, the safety tab  2408  axially locks the adjacent pin  104  relative to the male body  202 . The safety tab  2408  also blocks the rotation between the locking ring  216  and the pin  104 . The indexing tooth  106  is still cooperating with the indexing slot  206 . During the fitting, and using an approach consistent with that considered in EP-A-2,752,946, the pilot prongs electrically connect with their respective contacts after the electrical connection of the power circuits, by engagement of the power prongs in their power contact, has been done. This makes it possible to ensure that when the relays are activated upon closing by the pilot circuit, the current can effectively pass through the connector R to recharge the vehicle on the body  500  of which the female connector element  100  is mounted. The electrical connections occur between the configuration of  FIGS. 7 and 8  and the configuration of  FIG. 11 . In the coupled or fitted configuration, each of the prongs of the element  100  is electrically connected with its corresponding contact on the element  200 . 
     In the uncoupled configuration of  FIGS. 2 to 4 , the protection ring  280  is positioned around the front end of the locking ring  216 . It, together with the flywheel  218 , which has a substantially larger diameter than that of the body  202 , ensures that the sensitive elements of the male connector element  200 , such as its locking slots  222  and blocking ring  240 , do not come into direct contact with the ground when the male connector element  200  is grounded, which prevents these sensitive elements from being damaged. Indeed, the protection ring  280  and the flywheel  218  constitute protective members that radially surround the sensitive elements of the male element of the connector. 
     When the recharging of the vehicle equipped with the female connector element  100  is complete, the operator pulls on the blocking ring by exerting an axial force on the collar  2405 , said force being oriented toward the rear of the male connector element  200 , as shown by arrows F 2  in  FIGS. 12 and 13 . This makes it possible to withdraw the safety tab  2408  within each locking slot  222  and free the passage for the locking pins  104  toward the respective mouths  2222  of these pins. The operator then rotates the locking ring  216  using the flywheel  218 , in the direction opposite that previously mentioned. Since the balls  230  are partially received in the volume V 1 , they can progress in the grooves  2021  and do not oppose the rotation of the locking ring  216  around the body  202  in the uncoupling direction, i.e., in a rotation direction opposite arrow F 1 , which makes it possible to progress the locking pins  104  up to the mouths  2222 . During the progression of the locking pins  104  in the locking slots  222 , the pilot prongs are disconnected from the corresponding contacts, which cuts the power supply for the power circuits. By continuing this movement, the power prongs, then the ground prong are disconnected from their contacts. 
     At the end of the angular rotation range of the locking ring  216 , each ball  230  is across from a cavity  2023  and each locking pin  104  is in an aligned position relative to the mouth  2222  of a locking slot  222 , one of the mouths  2222  also being aligned with the mouth  2602 , since one of the pins  104  is aligned with the tooth  106 . The blocking ring  240 , which is released by the operator, is pushed forward again by the spring  260 , to the point that it again abuts against the locking ring  216 , which results in axially aligning the surface S 1  with the balls  230 , which are then engaged in the cavities  2023 , then kept in place in these cavities. Since the balls  230  kept in the cavities  2023  do not have the option of moving in the circumferential direction, the rotation of the locking ring relative to the body  202  is blocked again. The locking ring is thus immobilized in rotation around the body  202 , in a configuration where the mouth  2222  of one of the slots  222  is axially aligned with the mouth  2602  of the indexing slot  206 , which guarantees effective alignment of the three locking pins  104  with the mouths  2222  during a subsequent fitting operation of the elements  100  and  200  of the connector R, after the indexing members  106  and  206  are placed in cooperation. 
     Upon uncoupling, when the blocking ring  240  advances, each release tab  2407  also advances in the corresponding locking slot  222 , which results in pushing the locking pin  104  back toward the mouth  2222 , thus facilitating the uncoupling of the elements  100  and  200 . At the end of this operation, the female body  102  is removed from the male element  200  by the operator, and each pin  104  leaves its locking slot  222  by its mouth  2222 . The uncoupling is then effective and the male connector element  200  is ready for another connection, with its locking ring  216  angularly blocked in a configuration compatible with the placement of a new female connector element  100 . 
     Taking into account a situation where the vehicle whose body  500  is equipped with a female connector  100  leaves the recharging station  600  before disconnection by the operator, a safety uncoupling can be provided, by attaching the blocking ring  240  to a stationary point of the recharging station. Thus, a movement of the blocking ring relative to the recharging station is limited to the movement necessary for coupling. In this case, the withdrawal movement of the female connector element  100  borne by the body  500  of the vehicle moving away along the fitting axis XR, while the connector R is still coupled, drives the male body  202  and the locking ring  216  in the same movement of the vehicle, while the blocking ring  240  is retained on the recharging station  600 . This results in moving the blocking ring relative to the locking ring toward the rear of the male connector element  200 , which retracts the safety tab  2408  and frees the locking pins  104 , which are guided by the inclined front edges  2226  toward the mouths  2222  of the locking slots  222  and leave the slots by uncoupling the male and female elements of the connector R and limiting damage. 
     In light of the preceding, the invention has multiple advantages. 
     First of all, the obstacles formed by the balls  230  in their first blocking position makes it possible to keep the locking ring  216  in an angular position relative to the body  202  that is compatible with the coupling or fitting of the elements  100  and  200 , in particular with the automatic introduction of the locking pins  104  into the locking slots  222 , once the male and female bodies  102  and  202  are brought close together and angularly indexed owing to the cooperation of the tooth  106  and the slot  206 . The longitudinal bulk of the connector R is reduced relative to that known from EP-A-2,752,946, since the angular position of the locking ring is ensured by the ball(s)  230 , whereas it is not necessary to provide a wide entry bevel in the locking slots  222 . The movement of the blocking ring  240  is axial, therefore collinear to the coupling force that is transmitted to an axial surface of the blocking ring, namely the end face  2407   a  of the release tab  2407 , by the outer peripheral surface of the rollers  1044 . This configuration limits the coupling forces. 
     Furthermore, since the blocking ring  240  has an essentially axial movement and since it is pushed back directly by an axial surface connected to the body of the female connector element  100 , the retraction of the release tab  2407  is guaranteed for a given configuration of the locking pins  104  relative to the slots  222 . In particular, when the locking pins  104  are in contact with the release tab  2407  to push back the blocking ring  240 , the position of these pins can be guaranteed precisely relative to the slots  222  during the release of the rotation of the locking ring  240 . 
     The intermediate withdrawn position of the blocking ring  204  is reached when the pins  104  abut against the rear edges  2228  of the locking slots  222 . The rotation of the locking ring  216  in order to lock the pins  104  in the slots  222  is thus released when the pins  104  are fully engaged in a definite manner in the locking slots  222 , or in other words, when the entire periphery of each of the rollers  1044  is in a locking slot  222 . Thus, the rotation of the locking ring  216  necessarily drives the pins  104  toward their position locked in the closed end  2224  of each locking slot  222 . The release of the rotation of the locking ring  216  therefore takes place when this rotation actually allows locking of the pins  104 . 
     The position of the pins  104  is locked against any rotation in the unlocking direction, owing to the longitudinally immobile safety tab  2408 . The use of such a safety tab  2408  makes it possible to limit the tangential forces on the balls  230  in the coupled configuration. 
     Multiplying the balls  230  makes it possible to decrease the periodic contact force between the blocking ring  240  and each of these balls, when the connector R is in the coupled configuration. 
     Using release tabs  2407  and safety tabs  2408  angularly offset from one another makes it possible to scale down the coupling force to be provided on the locking ring  216 . 
     Furthermore and as shown in  FIG. 12 , the blocking ring  240  partially covers the locking pins  104  in the coupled configuration of the connector R. This ring thus protects the residual axial space between the locking ring  216  and the blocking ring  240 , with respect to dirt and/or pollution. 
     The separation of the blocking ring  240  into two assembled parts  2402  and  2404  makes it possible to select different materials for these two parts. In the case at hand, a harder material, such as quenched steel, can be used for the rear part  2404  in contact with the balls  230 , while a less strong material, such as aluminum, can be used for the front part that is in contact with the locking pins  104 . 
     The unblocking of the rotation of the locking ring is visible by the operator, since the blocking ring  240  is situated on the outside of the body  202  and in this case adopts a withdrawn position relative to the body  202 . 
     The invention is not limited to the embodiment described above, and several alternatives can be considered. 
     Alternatively, the withdrawn position of the blocking ring  204 , in which it frees the obstacles  230 , which can then move into their second released position, is reached when only part of each of the pins  104  is engaged in the locking slots  222 . 
     As mentioned above, the number of balls may be different from six. Likewise, the number of locking pins and slots  104  and  222  can be different from three. When several locking pins and slots are used, they are preferably distributed evenly around the axis XR. 
     Furthermore, the blocking ring  240  can be pushed back toward the rear by a portion of the female body  102  other than the roller  1044  of a locking pin  104 , in practice an axial surface of the female body  102  other than that of the locking pins  104 . This alternative requires a longer blocking ring to interact directly with the body  102  of the female connector element  100 . 
     Two cavities  2023  in the form of sphere portions can be provided, i.e., one at each end of the angular movement range of the locking ring  216  relative to the pin  104 . In the inner radial position, in their first blocking position, the balls  230  cooperate with the first spherical cavity to block the rotation of the locking ring relative to the second body in the uncoupled configuration and, in their second blocking position, with the second spherical cavity to block the rotation of the locking ring relative to the second body in the coupled configuration. The safety tabs  2408  can then be omitted, since the balls are kept in the second spherical cavities in the coupled configuration by the blocking ring in the forward position, which locks the rotation of the locking pins  104  within the locking slots  222 . 
     According to another alternative, each safety tab  2408  can be formed by a release tab. In this case, each safety tab is retracted by the corresponding pin  104  when the latter engages in the mouth  2222  of a slot  222  and this tab protrudes again in the slot  222  when it reaches its locked position, after relative rotation of the pin and the locking slot. Thus, the blocking ring  240  is movable relative to the body  202  between a forward position and a withdrawn position in which the rotation of the locking ring  216  is possible, the blocking ring  240  being in the forward position in the fitted configuration of the connector. 
     In the example of the figures, the release tab  2407  forms a single piece with the blocking ring  240 . This is not mandatory, and the release tab(s) may be made up of one or several rods fastened on the blocking ring. 
     According to another alternative, the connector may operate automatically upon connection. In other words, when the release tabs  2407  are completely retracted by the pins  104 , the pins  104  abut against the inclined rear edges  2228  of the locking slots  222 , and any action bringing the body  202  and the body  102  closer together creates a tangential component that rotates the locking ring. In this case, it is not necessary for the operator to exert torque on the flywheel  218 . 
     The indexing tooth  106  can be provided on the body  202 , while the indexing slot is provided on the body  102 . More than two indexing members  106  and  206  can be provided on the bodies  102  and  202 . In an alternative that is not shown, the indexing can be provided by the cooperation of a prong like the prong  112  with a complementary housing arranged on the insulator of the complementary connector element. The distribution of the indexing members relative to the locking pins and slots may differ from the described example. In particular, the pins and slots may not be evenly distributed around the axis XR. The indexing member of a connector element may not be angularly aligned with a locking slot or pin. The angular position of the locking ring, and therefore of each of the mouths of the locking slots, relative to the body of the second connector element, when the rotation of the locking ring is blocked by the obstacles, is chosen, relative to the indexing member of the second connector element, such that it corresponds to the angular position of the locking pins relative to the indexing member of the first connector element. Furthermore, the pins  104  can be single-piece pins. 
     Lastly, the distribution of the electric prongs and contacts  112 ,  212  and the like can be different from that which is illustrated. Some contacts may be mounted in the body  102 , while the corresponding pins are in the body  202 . 
     The embodiment and alternatives considered above may be combined to generate new embodiments of the invention.