Patent Description:
In order to charge an electric battery mounted in a vehicle such as an electric vehicle, hybrid electric vehicle, etc., the vehicle is provided with a charging inlet device. During an electric charging operation of the battery, a charging connector (or charging outlet device) of a charging station is mated with the charging inlet device of the vehicle and high charging currents are transmitted. This may result in a high thermal power dissipation in the charging inlet device or in the charging connector. For safety reasons, it is required to monitor the temperature of the charging inlet device and/or the charging connector in order to detect any overheating. In case that an important rise of temperature is detected, the charging current can be reduced or even switched off.

The document <CIT> discloses an electrical connector including a housing having a terminal channel with a power terminal in the terminal channel, and a temperature sensor assembly. The temperature sensor assembly includes a sealing pad holding the power terminal and a thermal shunt held by the sealing pad. The sealing pad is electrically insulative to electrically isolate the temperature sensor assembly from the power terminal, and thermally conductive. It is thermally coupled to the power terminal and to the thermal shunt. The terminal shunt is in contact with a thermal sensor. The thermal sensor monitors the temperature of the power terminal via a thermal path defined by the sealing pad and the thermal shunt. The thermal shunt is a solid body, separate and discrete from the sealing pad. It is manufactured separately from a highly thermally conductive material such as an aluminum oxide material, aluminum nitride, mullite, a thermally conductive plastic, a metal material (e.g., copper or aluminum), or a ceramic material.

The electrical connector disclosed in <CIT> has several drawbacks. A first drawback is that the temperature sensor assembly is rather complicated to manufacture because the thermal shunt is a body separate and discrete from the sealing pad, that must be manufactured separately and then coupled to the sealing pad and arranged against the thermal sensor. A second drawback is that the thermal path between the power terminal and the thermal sensor includes a solid body to solid body connection between the temperature sensor and the thermal shunt. The thermal shunt only touches a top surface of the thermal sensor. As a result, the thermal contact between the thermal sensor and the shunt is limited. A third drawback is that there may be a risk to damage the thermal sensor by pressing the thermal shunt against its top surface. As the thermal shunt is a rigid body (e.g. metal or ceramic), it has its own mass that can vibrate during car driving. This may cause micro cracks of the sensor's solder joints to the printed circuit board in the long run.

Therefore, there is a need for another kind of thermal path between the power terminal and the thermal sensor that is a good trade-off for overcoming the different drawbacks of the prior art.

The present disclosure concerns an electrical connector as defined in claim <NUM>.

The interior volume of the container is bigger than the thermal sensor so that the thermal sensor can be immersed in the thermal material, that is a thermally conductive material filling the container. Due to the thermal material, more heat travels to the thermal sensor and the heat transfer is faster. Such a configuration provides a better thermal contact between the thermal material and the thermal sensor than the thermal shunt described in <CIT>. In addition, it does not put a stress on the thermal sensor.

The seal has a first thermal conductivity and the thermal material has a second thermal conductivity. In some embodiments, the second thermal conductivity (thermal material) is higher than the first thermal conductivity (seal). In that case, the thermal material has better thermal conductive properties than the seal. However, the two thermal conductivities may be similar, or the thermal conductivity of the thermal material may even be higher than the thermal conductivity of the seal.

In an embodiment, the rear pocket is defined by a pocket wall protruding from said rear face.

Advantageously, the electrical connector further includes a printed circuit board having a front face on which the thermal sensor is mounted and the thermal material is compressed between the seal and the front face of the printed circuit board.

In an embodiment, the electrical connector further includes an inner housing, the printed circuit board is coupled to an inner housing, and the assembly of the printed circuit board and the inner housing is mounted to the rear chamber of the main housing and has a terminal opening receiving the power terminal.

In an embodiment, the electrical connector further includes an inner body holding a rear end portion of the power terminal, and the inner housing is coupled to the inner body.

In some embodiments, the electrical connector includes a number N of power terminals with N><NUM>, a number M of thermal sensors with <NUM>≤M≤N, and the seal has N terminal openings receiving the N power terminals respectively and M rear pockets forming M containers filled with the thermal material and receiving the M thermal sensors, immersed in the thermal material, respectively.

At least one rear pocket can be arranged in the space separating two adjacent terminal openings of the seal and the thermal sensor immersed in thermal material filling the corresponding container monitors the temperature of the two power terminals received in said two adjacent terminal openings.

The thermal material can have a viscosity adapted so that the thermal material does not flow out of a filled container and remains within the container when it is simply closed by placing a cover plate against the container's opening.

The present disclosure further concerns a charging inlet device to be mounted on a vehicle provided with an electric battery to be charged, including an electrical connector as previously defined.

The present disclosure further includes a vehicle including an electric battery and a charging inlet device as defined above.

The present disclosure also concerns a method as defined in claim <NUM>.

The method can include a step of mounting the thermal sensor on a front face of a printed circuit board and a step of compressing the thermal material filling the container formed by the rear pocket between the seal and the front face of the printed circuit board while immersing the thermal sensor in the thermal material.

The method can further include the steps of.

Other features, purposes and advantages of the disclosure will become more explicit by means of reading the detailed statement of the nonrestrictive embodiments made with reference to the accompanying drawings.

The present disclosure concerns an electrical connector <NUM> and a charging inlet device <NUM> that can be used as a charging inlet for a vehicle, such as an electric vehicle or hybrid electric vehicle. The charging inlet device <NUM> includes the electrical connector <NUM> and means (in other words: elements) for mounting the electrical connector <NUM> to a vehicle, such as a mounting flange <NUM>. The electrical connector <NUM> is intended to mate a charging connector (in other words: a charging outlet device) of a charging station.

The electrical connector <NUM> according to an embodiment of the present disclosure will now be described with reference to the <FIG>.

The electrical connector <NUM> has a main housing <NUM> and one or more power terminals <NUM>. The main housing <NUM> extends between a front and a rear. It has a front charging port <NUM> open towards the front of the main housing <NUM>. The front charging port <NUM> can include terminal channels (not shown).

In an embodiment, the electrical connector <NUM> has four power terminals <NUM>. Each power terminal <NUM> is coupled to (in other words: assembled with or mounted to) the main housing <NUM>. It has a contact pin <NUM> at a front of the power terminal <NUM> and a cable connector <NUM> at a rear of the power terminal <NUM>. The front contact pin <NUM> of each terminal <NUM> is arranged in the front charging port <NUM>, in a terminal channel. It is intended to be mated to a terminal of a charging connector (in other words: a charging outlet device), received in the terminal channel. The rear cable connector <NUM> is to be connected to a power cable of the vehicle connected to an electrical battery to be charged. The power terminals <NUM> extend parallel to each other along a longitudinal axis, as shown in <FIG>.

The main housing <NUM> and the mounting flange <NUM> can be formed in one single piece (in other words: the mounting flange <NUM> can be integral with the main housing <NUM>) or can be formed in two pieces joined together.

The electrical connector <NUM> is provided with a temperature monitoring system for monitoring the temperature of the power terminals <NUM> during charging. The charging power is controlled depending on the temperature of the power terminals <NUM>. In case that an important rise of temperature is detected (i.e., when the temperature exceeds a maximum temperature), the charging power can be reduced or even switched off.

The temperature monitoring system includes one or more thermal sensors <NUM>. In an embodiment, three thermal sensors <NUM> are used. The thermal sensors <NUM> are arranged in the rear chamber <NUM> of the main housing <NUM>.

The temperature monitoring system further includes a seal <NUM> holding the power terminals <NUM>. The seal <NUM> is coupled to (in other words: mounted to or assembled with) the main housing <NUM>. Optionally, it is sealed to the main housing <NUM>, for example by means of compressible ribs provided on the outer surface of the seal <NUM>. The seal <NUM> can be positioned at a front entrance of the rear chamber <NUM>, close to the front charging port <NUM>. In an embodiment, the seal <NUM> is a disk-shaped body. It is formed in one single piece. The seal <NUM> can extend in a plane orthogonal to the longitudinal axis of the power terminals <NUM>. The seal <NUM> is provided with terminal openings <NUM> to receive the power terminals <NUM>. The number of terminal openings <NUM> may correspond to the number of power terminals <NUM>.

The seal <NUM> is electrically insulative to electrically isolate the thermal sensors <NUM> from the power terminals <NUM>. Furthermore, the seal <NUM> is thermally conductive to transfer the heat from the power terminals <NUM> to the thermal sensors <NUM>, as will be explained in more details later. The seal <NUM> is part of a thermal path between each power terminal <NUM> and one or more thermal sensors <NUM>.

The seal <NUM> can be manufactured from a material including silicone and one or more additional substance(s) to increase its thermal conductivity (i.e., its property that determines how much heat will flow in the material) and its thermal diffusivity (i.e., its property that determines how rapidly heat will flow within the material). Illustrative and non-limitative examples of a material for the seal <NUM> include the products NL9330, NL9360 and HTV SC1230TC manufactured by the company Momentive Performance Materials Inc. Alternatively, it can be manufactured from other thermally conductive and electrically insulative materials.

In an embodiment, the seal <NUM> is a disk-shaped body. However, it could have any other shape. The seal <NUM> has a front face <NUM> and a rear face <NUM>, respectively facing the front and the rear of the main housing <NUM>. The rear face <NUM> of the seal <NUM> is provided with one or more rear pockets <NUM>. In an embodiment, the rear face <NUM> has three rear pockets <NUM>. Each pocket <NUM> forms a container, also termed as a gap, <NUM> that has been filled with a thermal fluid <NUM>, thermally conductive, and the thermal fluid <NUM> has taken the shape of the container <NUM>. In an embodiment, the rear pockets <NUM> are defined by pocket walls protruding from the rear face <NUM> of the seal <NUM>.

The terminal openings <NUM> of the seal <NUM> receive the corresponding power terminals <NUM>. The interior surface of each terminal opening <NUM> can have ribs that are sealed to the power terminals <NUM>. The ribs can be compressible. The rear pockets <NUM> are adjacent to the terminal openings <NUM>. Each rear pocket <NUM> can be provided with one or more contact surfaces <NUM> arranged in the extension of the interior surfaces of terminal openings <NUM>. Each contact surface has a shape that matches the external shape of the corresponding power terminal <NUM> to be contacted. Typically, the power terminals <NUM> are cylindrical and the contact surfaces <NUM> of the pockets <NUM> have the shape of a portion of a cylinder. Thanks to that, when a terminal opening <NUM> of the seal <NUM> receives the corresponding power terminal <NUM>, said power terminal <NUM> is in contact with the seal <NUM> not only via the interior surface of the terminal opening <NUM> but also via one or more pocket contact surfaces <NUM>. This improves the thermal contact between the power terminals <NUM> and the seal <NUM>.

Alternatively, the pockets <NUM> could be formed by hollows created in the rear face <NUM> of the seal <NUM>. In that case, each power terminal <NUM> is in contact with the seal <NUM> only via the interior surface of the corresponding terminal opening <NUM>.

In an embodiment, each pocket <NUM> of the seal <NUM> is arranged between two adjacent terminal openings <NUM> of the seal <NUM>. As shown in <FIG>, there are three pockets <NUM> in the spaces separating the four terminal openings <NUM> (adjacent to each other). In this way, in operation, a thermal sensor <NUM> immersed in the thermal fluid <NUM> filling a pocket <NUM>, that is intermediate between two adjacent terminal openings <NUM>, monitors the temperature of the two power terminals <NUM> received in the two adjacent terminal openings <NUM>.

Each thermal sensor <NUM> is immersed in the thermal fluid <NUM> filling a corresponding container (or gap) <NUM> and monitors the temperature of a power terminal <NUM> via a thermal path including the seal <NUM> and the thermal fluid <NUM>.

The thermal fluid <NUM> is made from a material that is highly thermally conductive. The seal <NUM> has a first thermal conductivity and a first thermal diffusivity. The thermal fluid <NUM> has a second thermal conductivity and a second thermal diffusivity that are higher than the first thermal conductivity and the first thermal diffusivity, respectively. For example, the material of the seal <NUM> can have a thermal conductivity around <NUM>,<NUM> to <NUM>,<NUM> W/m. K, and the thermal fluid <NUM> can have a thermal conductivity around <NUM>,<NUM> W/m.

The thermal fluid <NUM> is a material having the property to be deformable so that it can take the shape of a container filled with it. For example, the thermal fluid <NUM> can be a paste or a liquid foam. Preferably, the thermal fluid <NUM> has a certain viscosity so that it remains within the container <NUM> filled with it (in other words: so that it does not flow out of the container), at room temperature, when the container <NUM> is not hermetically closed, for example with a cover plate placed against the container's opening. The thermal fluid could also be a material that becomes solid after being dispensed in the containers <NUM>.

The temperature monitoring system further includes a printed circuit board <NUM>. The thermal sensors <NUM> are mounted on the printed circuit board <NUM>, her on a front surface of it. The thermal fluid <NUM> filling the containers <NUM> formed by the pockets <NUM> is compressed between the seal <NUM> and the printed circuit board <NUM>. Thermal sensors <NUM> are arranged in the containers <NUM> and immersed in the thermal fluid <NUM>. A small amount of thermal fluid <NUM> may have overflowed from each container <NUM> during the assembling and be compressed between the printed circuit board <NUM> and the edge of the container <NUM>.

The thermal fluid <NUM> can be made from materials used as thermal interface materials. An illustrative and non-limitative example of such a thermal interface material is SilCool® TGX <NUM> of the company Momentive Performance Materials Inc.

The thermal fluid <NUM> acts as a thermal bridge between the seal <NUM> and the thermal sensors <NUM>. As the thermal sensors <NUM> are immersed in the thermal fluid <NUM> filling the gaps or containers <NUM> formed by the rear pockets <NUM> of the seal <NUM>, the thermal contact between the thermal bridge <NUM> and the thermal sensors <NUM> is maximized, which improves the heat transfer between the power terminals <NUM> and the thermal sensors <NUM> as shown in <FIG>.

In an embodiment, the electrical connector <NUM> further includes an inner housing <NUM> coupled to the printed circuit board <NUM> and an inner body <NUM> holding a rear end portion of the power terminal <NUM>. The inner housing <NUM> is mounted to the rear chamber <NUM> of the main housing <NUM> and has terminal openings for receiving the power terminals <NUM>. The inner body <NUM> is coupled to the inner housing <NUM>.

The method of manufacturing the electrical connector <NUM> will now be described, with reference to the <FIG> and <FIG>.

The method has a step S1 of providing the main housing <NUM> and a step S2 of providing the seal <NUM>, as shown in <FIG>.

In a step S3, the seal <NUM> is coupled to the main housing <NUM>, as shown in <FIG>. The rear chamber <NUM> of the main housing <NUM> is open towards the rear and is provided with a front circular hollow <NUM> for receiving the disk-shaped seal <NUM> at the front of the chamber <NUM>, close to the front charging port <NUM>. As shown in <FIG>, the seal <NUM> can be provided with an opening <NUM> for receiving a positioning pin <NUM> of the main housing <NUM>, to facilitate the positioning of the seal <NUM> in the main housing <NUM>. The rear face of the seal <NUM> provided with the rear pockets <NUM> is oriented towards the rear of the main housing <NUM>.

The method further includes a step S4 of providing the thermal sensors <NUM> and a step S6 of providing an inner housing <NUM>, as shown in <FIG>. The thermal sensors <NUM> are previously mounted on a face of the printed circuit board <NUM>, in a step S5. The printed circuit board <NUM> and the inner housing <NUM> have corresponding openings including terminal openings for receiving the power terminals <NUM>. In a step S7, the inner housing <NUM> and the printed circuit board <NUM> are assembled together, as shown in <FIG>. The face of the printed circuit board <NUM> supporting the thermal sensors <NUM> is arranged towards the outside of the assembly of the inner housing <NUM> and printed circuit board <NUM>.

After placing the seal <NUM> in the main housing <NUM> in the step S3, the containers <NUM> formed by the rear pockets <NUM> of the seal <NUM> are filled with the thermal fluid <NUM>, in a step S8, as shown in <FIG>. Preferably, during the step S8, the seal <NUM> is positioned in a horizontal plane, the pockets <NUM> being open upwards. The thermal fluid <NUM> can be dispensed as a drop in the pocket containers <NUM>, for example using an injection device (as schematically illustrated in <FIG>). The volume of thermal fluid <NUM> dispensed in each container <NUM> approximatively corresponds to the interior volume of the container <NUM>, or a little bit less. The thermal fluid <NUM> dispensed in each container <NUM> takes the shape of the container <NUM>.

Then, in a step S9, the thermal sensors <NUM> are immersed in the thermal fluid <NUM> dispensed in the pockets <NUM> of the seal <NUM>. In the step S9, the assembly of the printed circuit board <NUM> and inner housing <NUM> is coupled to the assembly of the main housing <NUM> and seal <NUM>, as shown in <FIG>. The immersion of the thermal sensors <NUM> in the thermal fluid <NUM> is performed by pressing down the printed circuit board <NUM> on the fluid <NUM>, the plane of the seal <NUM> being horizontal (the rear pockets <NUM> open upwards). The thermal fluid <NUM> filling the containers <NUM> is thus compressed (in other words: sandwiched) between the seal <NUM> and the front face of the printed circuit board <NUM> while immersing the thermal sensor <NUM> in the thermal fluid <NUM>. The top surface of the thermal fluid <NUM> gets flattened. This may cause that a small amount of fluid <NUM> overflows the containers <NUM> and is compressed (in other words: sandwiched) between the edge of the containers <NUM> and the printed circuit board <NUM>.

The process further includes a step S10 of providing the power terminals <NUM>, as shown in <FIG>. The rear end portions of the power terminals <NUM>, provided with the cable connectors, are previously mounted to an inner body <NUM>. For example, the inner body <NUM> is disk-shaped. In the example shown in <FIG>, the inner body <NUM> has more precisely the shape of a partial (truncated) disk. In a step S11, the assembly of the inner body <NUM> and power terminals <NUM> is coupled to (in other words: assembled with, mounted to) the assembly of the inner housing, printed circuit board, seal and main housing, as shown in <FIG>. During the assembling, the power terminals <NUM> are inserted into the corresponding terminal openings provided in the inner housing <NUM>, the printed circuit board <NUM>, the seal <NUM>, and the main housing <NUM>. The disk-shaped inner body <NUM> is received in a corresponding disk-shaped compartment <NUM> of the inner housing <NUM>, shown in <FIG>. Once inserted into the assembly of the main housing <NUM> and inner housing <NUM>, the power terminals <NUM> come into contact with the interior surfaces of the terminal openings <NUM> of the seal <NUM> (here with the inside ribs of the terminal openings <NUM>) and with the contact surfaces <NUM> of the pockets <NUM>. Furthermore, the front contact pins of the power terminals <NUM> are arranged in the front charging port <NUM> of the main housing <NUM> (in the terminal channels).

In operation, the thermal sensors <NUM> immersed in the thermal fluid <NUM> filling the containers or gaps <NUM> of the pockets <NUM> of the seal <NUM> monitor the temperature of the power terminals <NUM> via a thermal path including the seal <NUM> and the thermal fluid <NUM>. The immersion of the thermal sensors <NUM> in the thermal fluid <NUM> allows to maximize the thermal contact between the thermal sensors <NUM> and the thermal bridge between the thermal sensors <NUM> and the seal <NUM>, provided by the thermal fluid <NUM>.

The thermal fluid <NUM> can be a paste or a liquid foam, at least when it is dispensed in the containers <NUM> formed by the pockets <NUM> (so that it can take the shape of the containers <NUM>). Then, the thermal fluid <NUM> can remain in the form of a viscous liquid or it may become solid.

In the present disclosure, the electrical connector <NUM> is a part of the inlet device on the vehicle side. However, the electrical connector could be implemented in a charging connector of a charging station.

An analogous system for monitoring the temperature could be provided in such a charging connector.

Claim 1:
An electrical connector (<NUM>) including
a main housing (<NUM>) extending between a front and a rear and having a front charging port (<NUM>) open towards the front and a rear chamber (<NUM>);
a power terminal (<NUM>) having a front contact pin arranged in the front charging port (<NUM>) and a rear cable connector;
a thermal sensor (<NUM>);
a seal (<NUM>), electrically insulative and thermally conductive, holding the power terminal (<NUM>) received in a terminal opening (<NUM>) of the seal (<NUM>), the seal (<NUM>) being thermally coupled to the power terminal (<NUM>) and to the thermal sensor (<NUM>);
characterized in that
the seal (<NUM>) has a rear face (<NUM>) provided with a rear pocket (<NUM>) forming a container (<NUM>) filled with a thermal material (<NUM>), thermally conductive, that is either a paste or a foam, in a viscous liquid form or solidified, and has taken the shape of the container (<NUM>), and in which the thermal sensor (<NUM>) is immersed,
and the thermal sensor (<NUM>) is configured to monitor the temperature of the power terminal (<NUM>) via a thermal path including the seal (<NUM>) and the thermal material (<NUM>).