Docking station for connector for electric vehicle charging station

A docking station for stowing an electrical connector adapted to connect a power source to a re-chargeable battery in a vehicle powered at least partially by the battery. The connector has a first end connected to a power cable for coupling the connector to the power source, and a second end that includes multiple first electrical terminals adapted to engage mating second electrical terminals in a receptacle. The second end also includes a protruding latching element adapted to engage a cooperating latching element in a receptacle for latching the connector to the receptacle. A stowing receptacle adapted to receive the second end of the connector when the connector is not in use includes an elongated recess adapted to receive the protruding latching element when the protruding latching element is located anywhere along the length of the elongated recess.

FIELD OF THE INVENTION

The present invention relates generally to electric vehicle charging stations (EVCSs), also referred to as electric vehicle supply equipment (EVSE), and, more particularly, to a docking station for use in an EVCS to stow the electrical connector used to charge the re-chargeable batteries in electric vehicles, when the connector is not in use.

BACKGROUND OF THE INVENTION

In the United States, the current standard for the “conductive charge coupler” used to connect an electrical power source to the electrical system of an electric is vehicle, to charge the vehicle battery, is the SAE J1772 standard. This standard applies to both the electrical inlet in the vehicle and the connector used to couple an electrical charging system to the vehicle inlet. The purpose of the coupler is to transfer energy to charge the battery and operate other vehicle electrical systems, to establish a reliable equipment grounding path, and to exchange control information between the vehicle and the supply equipment. The vehicle is typically equipped with an on-board charger capable of accepting energy from a single-phase AC supply network, converting the AC to DC, and regulating the supply voltage to a level that permits a managed charge rate based on the battery charge acceptance characteristics.

The J1772 connector and vehicle inlet include mating sets of electromechanical contacts that provide a physical connection at the vehicle interface for the power conductors, an equipment grounding conductor, a control pilot conductor, and a proximity sense conductor to provide a signal that helps reduce electrical arcing of the coupler during disconnect. Thus, the interface typically has five contacts that perform the interface functions. In addition, the coupler includes a latching mechanism to prevent inadvertent or accidental decoupling. The latching mechanism may also serve to properly align the connector with the vehicle inlet by requiring a latch element projecting from the connector to be registered with a cooperating latch element in the vehicle inlet.

An EVCS typically includes a docking station for stowing the electrical connector on the power cord when the connector is not being used. The mechanical receptacle for the connector on the end of the power cord is usually similar to the electrical receptacle in an electric vehicle, but without the electrical terminals. Because of the heavy gage of the power cord, it can be difficult for a user to properly align the connector with the stowing receptacle while attempting to dock the connector on the power cord. Thus, there is a need for an improved EVCS docking station that io facilitates the docking of the electrical connector when it is not in use.

SUMMARY OF THE INVENTION

When the J1772 connector is being stowed in an EVCS, the first physical contact typically occurs at the front end of the latching element that projects is from the connector. If this latching element is not properly aligned with its mating recess and latching element in the docking receptacle, it can become awkward for the user to manipulate the connector to the requisite position. The present invention alleviates this problem by significantly extending the latching element in the docking receptacle, while maintaining its latching function regardless of where it is first engaged by the latching element of the connector.

In accordance with one embodiment, the docking station is provided with an elongated latching recess adapted to receive and engage the projecting latching element of the connector anywhere along the length of the elongated recess. Thus, the connector can be successfully stowed as long as its latching element is located within the region defined by the extended length of the latching recess within the stowing receptacle.

In one implementation, the elongated latching recess in the stowing receptacle is an arched recess, e.g., extending along a 180-degree arc, in the upper portion of the stowing receptacle. A latching flange extends along the entire length of the elongated latching recess, so that the connector becomes latched to the docking station regardless of where the connector latching element first enters the latching recess. Thus, the cooperating latch elements latch the connector to the stowing receptacle as soon as the connector is pushed into the stowing receptacle.

The foregoing and additional aspects of the present invention will be apparent to those of ordinary skill in the art in view of the detailed description of various embodiments, which is made with reference to the drawings, a brief description of which is provided next.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Although the invention will be described in connection with certain preferred embodiments, it will be understood that the invention is not limited to those particular embodiments. On the contrary, the invention is intended to cover all alternatives, modifications, and equivalent arrangements as may be included within the spirit and scope of the invention as defined by the appended claims.

Turning now to the drawings,FIGS. 1A and 1Billustrate an electric vehicle charging station (EVCS)10that includes a pedestal11connected to an electrical power source such as the local electric utility grid. Electric vehicles are primarily powered by electric motors that draw from a rechargeable energy storage device such as a battery, as well as exchanging information. The vehicle typically has an electrical receptacle for receiving an electrical connector coupled to an electrical power supply for charging one or more batteries in the vehicle. As used herein, the term “electric vehicle” includes both vehicles that use only electrical power and hybrid vehicles in which the power train uses both an electrical power source and an internal combustion engine.

Within the pedestal11, the electrical power source is connected to one end of a power cable12via conventional safety devices such as a circuit breaker or fuse. The other end of the power cable12is connected to a first end of an electrical connector13(seeFIG. 2) within a handle14, to facilitate coupling the connector13to a power source such as an electrical distribution utility grid. The second end of the connector13is includes multiple first electrical terminals that are adapted to engage mating second electrical terminals in the vehicle inlet, i.e., the electrical receptacle that is standard equipment in electric vehicles. As mentioned above, the current standard for electrical connectors for charging electric vehicles in the United States is the SAE J1772 standard, for both the male and female electrical terminals used to connect the battery in an electric vehicle to an EVCS to re-charge the vehicle battery. The J1772 connectors include three detachable conductors for connecting and disconnecting the positive, negative and neutral lines of the electrical power source to the positive and negative terminals of the vehicle battery, and a vehicle ground terminal. The battery then receives and stores electrical power for future use by the vehicle.

When the charging station10is not in use, the power cable12from the pedestal11is looped around a bracket11aon the pedestal11, and the connector13is inserted into a docking station15on the pedestal11. The docking station15does not include any electrical connectors, but provides physical support and protection for the connector13when it is not in use. The docking station15is located at a preselected elevation on the pedestal11that is convenient for all users of the charging station10.

As can be seen inFIGS. 2 through 5, a protruding latching element20is formed by a finger that projects from the top of the connector13for holding the connector13onto a mating vehicle receptacle to prevent inadvertent or accidental decoupling. The protruding latching element20also serves to properly align the connector13with the vehicle receptacle so that the multiple conductors in the connector13properly register with the corresponding conductors in the vehicle receptacle. The vehicle receptacle receives the latching element20in a tapered socket that serves as a lead-in for automatic alignment during insertion of the connector. The latching element20can enter its socket in the vehicle receptacle only when the connector13is in the io proper angular position where the conductors in the connector are aligned with their mating conductors in the vehicle receptacle. When the latching element20engages a cooperating latching element in the vehicle receptacle, the latching engagement provides tactile and audible feedback to the user.

As can be seen inFIGS. 2 and 5, the latching element20projecting is from the top of the connector13is used to retain the connector in a stowing receptacle30that is part of the docking station15. As the latching element20is pushed into the receptacle30, a depending flange21on the front end of the latching element20snaps over a flange31projecting radially outwardly from a semi-circular rib32such that the flange31is on an outer end of the semi-circular rib32which is an inner side wall of a recess34that is part of the receptacle30. As can be seen inFIG. 4, the flanged rib32, which is the latching element of the receptacle30, extends around the top 180 degrees of the central portion of the receptacle30, forming a 180-degree arch.

In cooperation with the outer wall33of the receptacle30, the rib32also forms an elongated semicircular recess34so that the connector latching element20can be received by the receptacle30at any angular position falling within the 180-degree arch formed by the semicircular recess34, i.e., anywhere within the region encompassed by the opening of the elongated recess34. Thus, it is not necessary for the user to position the connector13so that the latching element20is located at the uppermost portion of the receptacle30, thus greatly simplifying the docking operation.

As can be seen inFIGS. 2 and 5, the outer wall33of the receptacle30forms a relatively large entry opening30a, and then tapers inwardly to guide the projecting latching element20of the connector13inwardly toward the semicircular recess34. When the front end of the latching element20engages the flange31of the rib32in the receptacle30, a tapered lower surface22on the front of the latch flange21cams the forward end of the latching element20upwardly (as viewed inFIGS. 2 and 5), against the urging of a biasing spring35(seeFIG. 2), so that the forward end of the latching element20passes over the flange31. The spring35then causes the forward end of the latching element20to snap back against the outer surface of the rib32, after the flange21clears the flange31. The overlapping flanges21and31then latch the connector13to the docking station15.

If the connector latching element20is located off-center in the arched recess34, such as one of the locations21aand21billustrated inFIG. 4, the handle14will be tilted rather than hanging straight vertically. Thus, the weight of the power cable12pulling on the lower end of the handle14will apply a torque to the handle14, urging the handle toward a straight vertical position. The latching flanges21and31is accommodate such movement of the handle14by permitting the flange21to slide along the outer surface of the rib32behind the flange31, thus holding the handle14latched to the stowing receptacle30. The latching flange31extends along the entire length of the rib32, so that latching of the two flanges21and31can be initiated at any point along the length of the recess34

The latching element20is pivoted on a shaft23(seeFIG. 2) so that the front end of the latching element20can be pivoted upwardly by pushing down on an actuator button20aformed as an integral part of the trailing end portion of the latching element20. The button20aprotrudes out through a hole in the top wall of the handle14so that the button20ais accessible from the exterior of the handle14so that a user can manually press the button20ato release the latch when it is desired to remove the handle14from the receptacle30(when releasing the connector from a vehicle inlet, the actuator button20amay also open a switch to trigger a vehicle charge control to provide controlled shutoff of charge power prior to disconnection). Pressing the actuator button20atilts the front end of the latching element20upwardly against the biasing force of the spring35so that the flange21clears the latching flange31of the stowing receptacle30, thereby allowing the handle14and the connector13to be removed from the stowing receptacle.

Referring toFIGS. 2 and 5, the stowing receptacle30is nested within a cavity40formed by a housing41attached to the pedestal11by multiple screws42. The rear surface of the cavity40forms a central opening43surrounded by a circular flange44that receives a base45. A screw46extends through a central hole in the base45and is threaded into a hub47projecting from the rear surface of the receptacle30. This captures the receptacle30within the cavity40while still allowing limited axial movement of the receptacle30relative to the walls of the cavity40because the head of the screw46can move axially within its recess48in the rear surface of the base45. A coil spring49fits over matching hubs50and51formed by the receptacle30and the base45, respectively, and biases the receptacle30to the advanced position illustrated inFIGS. 2 and 5, where the head of the screw46engages the bottom of its recess48. When pressure is applied to the receptacle30urging it further into the cavity, as occurs when is the connector13is being stowed in the receptacle30, the receptacle30can move inwardly against the biasing force of the spring49, so that the receptacle can yield to such pressure, until the receptacle30engages the wall of the cavity40. The receptacle30can also tilt slightly within the cavity40, again until the receptacle30engages the wall of the cavity40. This provides a soft feel to a user attempting to stow the connector13in the receptacle30, and avoids a sharp impact or vibration as the connector13reaches its fully stowed position.