Patent Description:
With the increasing use of electric and hybrid propulsion systems in heavy vehicle, it also becomes increasingly important to provide high-voltage systems which are reliable and easily serviceable. In particular, components which are subjected to wear, and which may require replacement are advantageously easily replaceable in the vehicle. Preferably, it should be possible to remove and replace components in a high-voltage system such as contactors, fuses and pre-charge components within a matter of minutes and without having to take the vehicle to a workshop. Accordingly, it is desirable to provide improved components for high-voltage systems which facilitate fast and easy replacement.

<CIT> describes a an electromagnetically operated multiple contact relay of the parallel leaf spring type. The relay comprises an envelope including a tubular intermediate envelope portion arranged about a longitudinal axis and end walls closing opposite ends of the tubular intermediate envelope portion to define a hermetically sealed main chamber, and movable contacts in the main chamber to make or break a circuit.

According to a first aspect of the disclosure, it is provided a component for a high-voltage electric system of a vehicle, the component comprising: a hollow body having a circular cross section; a first contact arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body; a second contact arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body, the second contact area being separated from the first contact area in the axial direction of the body; an axially movable connector element arranged within the body; and an electromagnetic relay arranged to control axial movement of the connector element, wherein the relay is configured so that actuation of the relay results in an axial movement of the connector element to form an electrical connection between the first contact and the second contact.

The first aspect of the disclosure seeks to provide an improved high-voltage component for a vehicle which is both safe as well as fast and easy to replace when needed. A technical benefit may include that the described component provides a plug-n-play functionality where the component is ready to be used as soon as it is installed and that the component can easily be accessed from an outside of the high-voltage electric system. A further advantage of the described component is that no alignment is required which significantly reduces the risk of a faulty installation. It also possible to configure the component so that it can be installed and removed without using tools.

The first aspect of the disclosure also seeks to provide a connection mechanism within the component which is both secure and reliable. This can be achieved by the described relay-controlled connector element which is operable to switch between an open and a closed electrical circuit by controlling the axial position of the connector element. In particular, a safe disconnection mechanism can be provided in a high-voltage system by breaking a mechanical and electrical connection through physical movement of the connector element.

The connector element comprises a rod, a first flange attached to the rod and arranged to form a connection with the first contact and a second flange attached to the rod and arranged to form a connection with the second contact upon actuation of the relay. The rod and the first and second flanges are all made from an electrically conductive material. Accordingly, each of the first and second flange of the connector element form a physical and electrical connection with the respective first and second contact of the component when the relay is actuated. The rod will thereby form a conductive path between the first and second contact. A technical benefit may include that the area of contact is defined by the flange and a large surface area can be achieved which may be required in high-voltage systems operating with high currents.

In some examples, at least one of the first and second contact extends into the interior of the body. A technical benefit may include that a simplified connection mechanism is provided where a connector element can more easily form a connection with the contact within the exterior of the body. It would however also be possible to have first and second contacts which are integrated in the wall of the body and where the connection element is configured forms a connection to the respective contacts by contacting the inner sidewall of the body at the location of the contacts.

In some examples, at least one of the first and second contact comprises a central opening through which the connector element is arranged. A technical benefit may include that the rod of the connector element can then run through the opening of the contact which provides an advantageous mechanical arrangement where the opening of the first and/or second contact acts as a guide for the rod to prevent misalignment of the connector element.

In some examples, the rod comprises an insulating sheath. A technical benefit may include that the surface of the rod is protected from wear and the rod is also electrically insulated to prevent unwanted electrical connections. In examples where the rod is arranged to pass through an opening of a contact, it is particularly desirable to use an insulating sheath to prevent an electrical connection between the rod and the contact.

In some examples, the insulating sheath comprises at least one opening enabling an electrical connection to be formed to the rod. A technical benefit may include that by providing an opening in the sheath, additional electrical connections to the connecting element can be formed without having to add further flanges or the like. The location of the opening in the sheath can be arranged so that electrical contact is formed with the rod when the connecting element is in a position where there is no connection between the first and second contacts. It is also possible to form a plurality of openings in the sheath in the same manner.

In some examples, the component further comprises a third and a fourth contact each contact being arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body. The third and fourth contacts may for example be low-voltage terminals for controlling functionality of the component. A technical benefit may include additional functionality can be included in the component.

In some examples, the third and fourth contacts are connected to the electromagnetic relay to control actuation of the electromagnetic relay. A technical benefit may be that also the contacts for controlling the electromagnetic relay are integrated in the component and thereby protected.

In some examples, the electromagnetic relay is a multi-stage electromagnetic relay where the axial position of the connecting element can be controlled to be in at least two different actuated positions in addition to a rest-position when the relay is not actuated. A technical benefit may include that more complex functionality can be provided by one and the same component such as circuitry where events need to occur sequentially. An example is where the component comprises a pre-charge resistor to be engaged prior to connection of the high-voltage system as a whole, where the pre-charge resistor can be connected in a first actuation stage.

In some examples, the multi-stage electromagnetic relay comprises a first spring so that a first stage actuation of the relay requires a first actuation force and a second spring so that a second stage actuation of the relay requires a second actuation force higher than the first actuation force. A technical benefit may include that the two stages of the relay can be controlled by controlling the actuation force provided to the relay, for example by controlling pulse-width modulation (PWM) of a control signal provided to a solenoid of the electromagnetic relay.

In some examples, the component further comprises a pyro fuse configured to destructively break the connection element upon actuation of the pyro fuse. The pyro fuse can for example be controlled via the third and fourth contacts described above or separate contacts may be added specifically for controlling the pyro fuse. A technical benefit may include that when the pyro fuse is integrated in the component, controlled and safe destruction of a selected connection element can be achieved without influencing other components in the system, and the specific component where the pyro fuse has been actuated can be individually replaced.

In some examples, the component further comprises a fifth contact arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body. A technical benefit may include that the fifth contact is arranged in connection with an additional device in the component such as a pyro fuse, a pre-charge resistor or any other device integrated in the component in addition to the contactor defined by the connection element.

In some examples, the body of the component has a substantially cylindrical shape. The body thus has a circular cross-section which has substantially the same diameter over the length of the component, with the exception of an end cap which may have a larger diameter. A technical benefit may include that the component is easy to install and that the component does not require alignment when being installed. Moreover, a cylindrical shape enables the use of many commonly used fastening mechanisms for securing the component in a socket.

In some examples, the body is tapered in a direction away from the cap. The body thus has a circular cross-section which has a decreasing diameter over the length of the component in a direction away from the cap. A technical benefit may include that the component may more easily fit into a correspondingly conical socket.

In some examples, at least one of the first and second contact area is threaded and configured to be threaded into a receiving socket, thereby forming a fastening mechanism or part of a fastening mechanism of the component. A technical benefit may include that a good electrical and mechanical connection can be ensured by the threaded contact areas when the component is installed in a socket. Moreover, the threaded connection may be sufficient so that no further fastening mechanism is required, thereby simplifying the design of the component.

In some examples, the component further comprises a cap comprising a seal ring configured to form a seal against a socket. A technical benefit may include that a closed seal is formed between the component and a socket so that the contacts are fully protected from the external environment, thereby reducing the risk of corrosion and other types of degradation of the contacts. The components may preferably be located so that they are easily accessible from an outside of the vehicle which in turn may expose the components to water, dirt and the like, making a secure seal advantageous to protect the contact areas.

In some examples, there is also provided a connector assembly comprising a component according to any one of the aforementioned examples and a socket configured to receive the component. The shape and configuration of the socket would then have electrically conductive contact areas corresponding to the contact areas of the component. Moreover, the socket is connected to and forms part of the high-voltage system of the vehicle so that the component is ready to be used as soon as it is installed in the socket.

Present solutions for replaceable components in high voltage systems for example include a removable service box which encapsulates previously stated components together with several additional components in one removable package. This drives significant cost and design complexity due to additional components required to secure ease of service while maintaining degree of safety and system integrity. Moreover, such solutions may also fail to meet increased serviceability requirements where it is desirable that certain components should be replaceable without having to visit a workshop or the like.

<FIG> is an exemplary component <NUM> for a high-voltage electric system of a vehicle and.

<FIG> is a cross section view of the component <NUM>. The component comprises a hollow body <NUM> having a circular cross section. The body <NUM> is substantially cylindrical and the body <NUM> is made from an electrically insulating material. Moreover, the body <NUM> is preferably hermetically sealed and may also be gas filled, for example by an inert gas, in part to protect the elements within the body and also to reduce the risk of arcing or the like inside the component <NUM>.

The component further comprises first and second electrically conductive contacts <NUM>, <NUM> arranged circumferentially in the body <NUM> and configured to be externally exposed and to reach an interior of the body <NUM>, wherein the second contact <NUM> is separated from the first contact <NUM> as seen in the axial direction of the body <NUM>. Both the width and the separation distance of the first and second contacts <NUM>, <NUM> can be selected to ensure that there is no arcing or currents between the first and second contacts <NUM>, <NUM>. The properties of the first and second contacts <NUM>, <NUM> can thereby be based on the properties and requirements of a particular high-voltage electric system.

In the present description, the first and second contacts <NUM>, <NUM> are illustrated to reach all the way around the component <NUM> to provide a circular contact area. However, the first and second contacts <NUM>, <NUM> may equally well be sectioned and/or divided into separate area portions along the circumference of the component <NUM> while still providing the same technical effects and benefits as contacts reaching all the way around the component <NUM>. The first and second contacts <NUM>, <NUM> may for example be formed by metal rings, such as copper rings, to provide good electrical conductivity. Moreover, the first and second contacts <NUM>, <NUM> are arranged to reach an interior of the body <NUM> to form an electrical connection from the outside of the component <NUM> to within the hollow body <NUM>.

As illustrated in <FIG>, the component <NUM> further comprises an axially movable connector element <NUM> arranged within the body <NUM>, and an electromagnetic relay <NUM> arranged to control axial movement of the connector element <NUM>. The relay <NUM> is configured so that actuation of the relay <NUM> results in an axial movement of the connector element <NUM> to form an electrical connection between the first contact <NUM> and the second contact <NUM> through the connector element <NUM>.

As illustrated in <FIG>, the connector element <NUM> comprises a rod <NUM>, a first flange <NUM> attached to the rod <NUM> and arranged to form a connection with the first contact <NUM> and a second flange <NUM> attached to the rod <NUM> and arranged to form a connection with the second contact <NUM> upon actuation of the relay <NUM>. In the illustrated example, the first and second flanges <NUM>, <NUM> are tapered in a shape corresponding to a recess in the respective first and second contacts <NUM>, <NUM> in order to ensure good mechanical and thereby electrical connection between the flange and the contact. At least the first contact <NUM> is thus open, i.e. ring-shaped, at a central portion of the contact and the rod <NUM> of the connector element <NUM> is arranged through the opening so that the rod <NUM> can move in an axial direction of the component <NUM>. It should be noted that the exact shape of the contacts and the connector element <NUM> may be modified in many different ways while still providing the described functionality of the inventive concept.

Moreover, the rod <NUM> of the connector element <NUM> comprises an insulating sheath <NUM> which is arranged around the rod <NUM> to prevent an electrical contact between the rod <NUM> and the first contact <NUM> when the connector element is in a non-actuated position.

The electromagnetic relay <NUM> is here represented by a spring loaded connection element <NUM> arranged together with a solenoid <NUM>. The spring <NUM> is arranged to maintain the component in a disconnected state when no voltage is applied to the solenoid. Once a sufficiently high voltage is applied to the solenoid <NUM>, an electromagnetic force acts on the connector element <NUM> to overcome the spring force and to form an electric connection between the first contact <NUM> and the second contact <NUM> through the rod <NUM>.

The illustrated component <NUM> further comprises a cap <NUM> attached to an end portion <NUM> of the body <NUM>. The cap <NUM> is here is here represented by a circular plate at the end portion <NUM> of the body <NUM> and the cap <NUM> is further illustrated to comprise a seal <NUM> in the form of a rubber gasket or the like configured to form an environmental seal when the component <NUM> is arranged in a corresponding socket. In general, the seal <NUM> may comprise an O-ring or a washer. It should however be noted that both the end cap <NUM> and the seal <NUM> may be configured in many different ways while still providing the desired functionality.

In some examples, the component <NUM> further comprises third and fourth contacts <NUM>, <NUM> each arranged circumferentially on the body, and configured to be externally exposed and to reach an interior of the body. The third and fourth contacts <NUM>, <NUM> are for example low-voltage terminals and the third and fourth contacts <NUM>, <NUM> can consequently be made smaller as illustrated in <FIG> since they do not have to carry the same amount of current as the high-voltage contacts <NUM>, <NUM>. The low-voltage terminals <NUM>, <NUM> may for example provide gnd and vcc terminals for control signals for actuation of the electromagnetic relay <NUM>. The third and fourth contacts <NUM>, <NUM> are thereby electrically connected to a device within the component. In the present context, a low voltage is typically in the range below 48V, such as nominal voltage values of <NUM> V, <NUM> V, <NUM> V or <NUM> V to be used for control signals. High-voltage in the present context refers to voltages above <NUM> V, and in a high-voltage electric system of a vehicle the high voltage may be the so called traction voltage with voltages in range between <NUM> V and <NUM> V. The skilled person readily realizes that the number of terminals for both high-voltage and low-voltage connections can be increased or decreased depending on the required functionality for a particular application.

<FIG> schematically illustrate an example where the component further comprises a fifth contact <NUM> arranged circumferentially in the body <NUM> and configured to be externally exposed and to reach an interior of the body <NUM>. The fifth contact <NUM> is here arranged between the first and second contacts <NUM>, <NUM> as seen in an axial direction of the cylindrical body <NUM> of the component <NUM>. Moreover, the insulating sheath <NUM> of the rod <NUM> comprises an opening <NUM> enabling an electrical connection to be formed between the rod <NUM> and the fifth contact <NUM>.

In example illustrated in <FIG>, the electromagnetic relay is a multi-stage electromagnetic relay meaning that the relay can be controlled to actuate the connector element <NUM> in several distinct stages. The multi-stage electromagnetic relay <NUM> comprises a first spring <NUM> so that a first stage actuation of the relay requires a first actuation force and a second spring <NUM> so that a second stage actuation of the relay requires a second actuation force higher than the first actuation force.

<FIG> illustrates the first stage of actuation where the connector element <NUM> is moved in an axial direction away from the cap <NUM> but without forming a connection between the first and second contacts <NUM>, <NUM> since the flange <NUM> of the connector element <NUM> is not in contact with the corresponding contact <NUM> of the component. Instead, a connection is formed between the first contact <NUM> and the fifth contact <NUM> via the rod <NUM> and through the opening <NUM> in the insulating sheath <NUM>. The fifth contact <NUM> can for example be used to connect a battery to an external pre-charge resistor in a first stage of connection. In some examples, the component may be connected to another component of similar configuration which comprises the pre-charge resistor.

<FIG> illustrates the second stage of actuation where the connector element is fully actuated and moved in a direction away from the cap <NUM> so that an electrical connection is formed between the first contact <NUM> and the second contact <NUM>, for example to fully connect an energy storage system of a vehicle to power consumers such as traction motors. In particular, the first contact <NUM> is connected directly to the rod <NUM> and the second contact <NUM> forms a contact to a flange <NUM> of the connector element <NUM>. However, electrical connection between the first contact and the connector element may also be formed using a flange as illustrated in <FIG>, and other configurations of the connector element are possible to achieve the described two stage connection.

In an example illustrated in <FIG>, the component <NUM> further comprises a pyro fuse <NUM> configured to destructively break the connection element <NUM> upon actuation of the pyro fuse. The pyro fuse <NUM> could for example be controlled via the same PWM signal that controls the electromagnetic relay <NUM>. For example, <NUM>% duty cycle of PWM could be configured to blow the pyro fuse. It would also be possible to provide additional circumferentially arranged low-voltage contacts to provide a control signal for triggering the pyro fuse <NUM>.

<FIG> schematically illustrate a socket <NUM> configured to receive a component <NUM>. The socket <NUM> and component together form a connector assembly <NUM>. In the illustrated example, the socket <NUM> comprises a first electrical spring contact <NUM> arranged to form a contact with the first contact <NUM> and a second electrical spring contact <NUM> arranged to form a contact with the second contact <NUM> of the connector. The first and second electrical spring contacts <NUM>, <NUM> are configured to have an inner diameter which is smaller than an outer diameter of a respective contact <NUM>, <NUM> such that the central portion <NUM> of the spring contact <NUM>, <NUM> press against the respective contact area <NUM>, <NUM> when the component <NUM> is inserted into the socket <NUM>, thereby forming an electrical connection between the component and the socket <NUM>.

The socket <NUM> may advantageously also be configured to prevent or at least reduce the risk of insertion of foreign objects into the socket when no component is installed therein. The socket may for example comprises a seal (not shown) which both prevent insertion of foreign objects, and which protects the interior of the socket from dirt, water and the like when no component is installed.

<FIG> is a schematic illustration of an exemplary vehicle <NUM> comprising a component <NUM> according to one example of the inventive concept. Here it is illustrated that the component is easily accessible for improved serviceability of the vehicle <NUM>.

Claim 1:
A component (<NUM>) for a high-voltage electric system of a vehicle, the component comprising:
a hollow body (<NUM>) having a circular cross section;
a first contact (<NUM>) arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body;
a second contact (<NUM>) arranged circumferentially in the body and configured to be externally exposed and to reach an interior of the body, the second contact being separated from the first contact in the axial direction of the body;
an axially movable connector element (<NUM>) arranged within the body; and
an electromagnetic relay (<NUM>) arranged to control axial movement of the connector element, wherein the relay is configured so that actuation of the relay results in an axial movement of the connector element to form an electrical connection between the first contact and the second contact,
whereby the connector element comprises a rod (<NUM>), characterised by a first
flange (<NUM>) attached to the rod and arranged to form a connection with the first contact and a second flange (<NUM>) attached to the rod and arranged to form a connection with the second contact upon actuation of the relay.