Patent ID: 12230465

DETAILED DESCRIPTION

The present disclosure will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the present disclosure are shown. Terms or words used in the present specification and claims should not be interpreted as being limited to typical or dictionary meanings, but should be interpreted as having meanings and concepts, which comply with the technical aspects of the present disclosure, based on the principle that an inventor can appropriately define the concept of the term to describe his/her own application in the best manner.

Therefore, configurations illustrated in the embodiments and the drawings described in the present specification are only embodiments of the present disclosure and do not represent all of the technical aspects of the present disclosure, and thus it is to be understood that various equivalents and modified examples, which may replace the configurations, are possible when filing the present disclosure.

A relay switch device to be described below is installed in a high current transmission line for transmitting the power of a battery pack to an electric vehicle (EV) or a hybrid vehicle (HV) and is used to control an electrical connection between the battery pack and a load of a vehicle. However, the scope of the present disclosure is not limited by this purpose. For example, a relay switch device according to the present disclosure may be installed in a charging current line connecting an external charger to a battery pack.

FIG.3is a view schematically illustrating a structure of a relay switch device according to an embodiment of the present disclosure, andFIG.4is a perspective view of a circuit mode switch module ofFIG.3.

Referring toFIGS.3and4, the relay switch device according to an embodiment of the present disclosure includes a relay housing100, a first upper fixing terminal210, a second upper fixing terminal220, a first lower fixing terminal310, a second lower fixing terminal320, a circuit mode switch module400, and a driving module500.

The relay housing100may be referred to as an injection structure for accommodating and protecting components to be described later in an interior space in a substantially rectangular box shape. For example, the relay housing100may include a lower cover and an upper cover that are injection-molded using a plastic resin, may be configured to accommodate components to be described later on the lower cover and assemble the upper cover, and may be provided to be fixed to a battery disconnect unit (BDU) housing (not shown) by using a bolt or the like.

The relay housing100may be manufactured in various shapes according to need. A window may be provided in the relay housing100or may be made of a transparent acrylic material, so that an operation state of the relay housing100may be visually checked.

The relay switch device is connected to an external current transmission line through the first upper fixing terminal210and the second upper fixing terminal220. For example, outside the relay housing100, the first upper fixing terminal210may be connected to a line extending to a battery pack, and the second upper fixing terminal220may be connected to a line extending to a load of an electric vehicle. The lines may be implemented by using bus bars, wires, or the like.

The first upper fixing terminal210and the second upper fixing terminal220may be arranged side by side with a predetermined distance from each other in a horizontal direction (±X-axis direction) across the inside and outside of the relay housing100.

As shown inFIG.3, the first upper fixing terminal210and the second upper fixing terminal220may be provided as a pair in the same shapes, and may be fixedly mounted on an upper end portion of the relay housing100. The first upper fixing terminal210and the second upper fixing terminal220are forcedly fitted into two holes formed in the upper end portion of the relay housing100, so that respective portions of the first upper fixing terminal210and the second upper fixing terminal220are inside the relay housing100and the remaining portions thereof are exposed to the outside of the relay housing100.

Accordingly, for example, when a contact plate420to be described later contacts the first upper fixing terminal210and the second upper fixing terminal220physically apart from each other, a current may flow in the current transmission lines.

A first lower fixing terminal310may be provided apart from the first upper fixing terminal210by a predetermined distance in a vertical downward direction, and a second lower fixing terminal320may be provided apart from the second upper fixing terminal220by a predetermined distance in the vertical downward direction.

The first lower fixing terminal310and the second lower fixing terminal320may be provided as a pair in the same shapes, namely, in a metal plate shape, and may be spaced apart from each other and fixedly mounted within the relay housing100.

The first upper fixing terminal210and the first lower fixing terminal310are connected to each other via wire or busbar so that a current may flow between the first upper fixing terminal210and the first lower fixing terminal310, and likewise, the second upper fixing terminal220and the second lower fixing terminal320are connected to each other via wire or busbar so that a current may flow between the second upper fixing terminal220and the second lower fixing terminal320.

For example, the first lower fixing terminal310and the second lower fixing terminal320may be fixedly mounted on partition walls110provided in an upper end portion of the driving module500by bonding, bolting, snap-fit welding, or the like. When the relay housing100is manufactured, the first lower fixing terminal310and the second lower fixing terminal320may be integrated with the relay housing100by insert injection.

According to the present embodiment, the first upper fixing terminal210is connected to the first lower fixing terminal310by using a first metal wire610. One end of the first metal wire610may be welded to the first upper fixing terminal210, and the other end thereof may be welded to the first lower fixing terminal310. Similarly, the second upper fixing terminal220is connected to the second lower fixing terminal320by using a second metal wire620.

The circuit mode switch module400may be configured to move a predetermined distance to selectively contact the first and second upper fixing terminals210and220or the first and second lower fixing terminals310and320. The circuit mode switch module400may be configured so that respective node voltage values at the first and second upper fixing terminals210and220are substantially the same as each other when the circuit mode switch module400contacts the first upper fixing terminal210and the second upper fixing terminal220and a voltage difference is generated between the first upper fixing terminal210and the second upper fixing terminal220when the circuit mode switch module400contacts the first and second lower fixing terminals310and320.

Such a configuration of the circuit mode switch module400enables switch from a pre-charge relay circuit mode to a main relay circuit mode or switch from the main relay circuit mode to the pre-charge relay circuit mode.

The pre-charge relay circuit mode may be referred to as a mode in which a current in a load gradually increases due to provision of an RC circuit between a battery pack and the load, and the main relay circuit mode may be referred to as a mode in which, when the magnitude of the current is a degree that does not affect the load, a current is supplied to the load without pre-charge resistance.

In detail, referring toFIGS.3and4, the circuit mode switch module400according to the present embodiment includes a moving shaft410, a contact plate420, and a resistive member430.

The moving shaft410may be disposed in an up-down direction (±Y-axis direction) and configured to be movable up and down within the relay housing100. The present embodiment includes the driving module500including a coil portion510generating an electromagnetic force to drive the moving shaft410up and down.

The coil portion510may be separated from the first lower fixing terminal310and the second lower fixing terminal320by the partition wall110, and may be interposed in a space surrounded by the partition wall110and an outer wall of the relay housing100.

The coil portion510may be provided in a cylindrical shape with a central passage having an empty center. The moving shaft410may be disposed along the central passage, and an upper end thereof may be located in an upper region of the relay housing100.

When a current flows in the coil portion510due to application of power, the coil portion510may act as an electromagnet. At this time, the moving shaft410may move upward or downward by the electromagnetic force of the coil portion510.

For example, when the current is flowed to the coil portion510in one direction, the moving shaft410may move upward, and, when the current is flowed to the coil portion510in an opposite direction to the one direction, the moving shaft410may move downward. Alternatively, two coil portions510, namely, a coil portion510for ascending the moving shaft410and a coil portion510for descending the moving shaft410, may be used.

A moving core520capable of serving as a weight may be coupled to a lower end of the moving shaft410. The moving core520may have a larger diameter and a higher weight than a diameter and a weight of the moving shaft410. This moving core520limits a rapid movement of the moving shaft410.

A fix core530having a hollow shape may be further provided in the central passage of the coil portion510. An inner diameter of the fix core530is larger than the diameter of the moving shaft410so that the moving shaft410passes through the fix core530, and is smaller than the diameter of the moving core520.

The fix core530may be located in the central passage of the coil portion510to suppress a left and right flow of the moving shaft410and guide an elevating action, and may serve as a stopper that prevents the moving shaft410connected to the moving core520from being pushed up above a predetermined height, by limiting a movement of the moving core520. When the moving core520and the fix core530are used, a movement of the moving shaft410may be more stably and precisely controlled.

According to the present embodiment, an electro-mechanical method using the coil portion510is employed to elevate and lower the moving shaft410. However, as an alternative example, a mechanical mechanism using, for example, a combination of a rack, a pinion gear, and a servo motor or a pneumatic cylinder, may be employed to elevate and lower the moving shaft410.

The contact plate420may be formed of an electrically conductive material and may be provided in the shape of a block or plate having a larger length than an interval between the first upper fixing terminal210and the second upper fixing terminal220so that a center of the block or plate is coupled to an uppermost end of the moving shaft410.

When the moving shaft410ascends to a predetermined location, the contact plate420contacts the first upper fixing terminal210and the second upper fixing terminal220. At this time, the first upper fixing terminal210and the second upper fixing terminal220are electrically connectable to each other through the contact plate420, and thus a voltage is substantially constant between the first upper fixing terminal210and the second upper fixing terminal220.

The resistive member430may include a resistor, an insulating case in which the resistor can be accommodated, and a first terminal431and a second terminal432connected to the resistor.

The first terminal431may have a button shape and may protrude from one portion of the lower surface of the resistive member430, and the second terminal432may have a button shape and may protrude from the other portion of the lower surface of the resistive member430. The one portion refers to a portion corresponding to a vertical upper portion of the first lower fixing terminal310, and the other portion refers to a portion corresponding to a vertical upper portion of the second lower fixing terminal320.

The resistive member430may be provided below the contact plate420to be coupled to the moving shaft410.

According to this structure, when the moving shaft410descends to a predetermined location, the first terminal431of the resistive member430comes into contact with the first lower fixing terminal310and the second terminal432of the resistive member430comes into contact with the second lower fixing terminal320. At this time, the first lower fixing terminal310and the second lower fixing terminal320enter a state capable of being electrically connected to each other, and, when a current flows through the first lower fixing terminal310and the second lower fixing terminal320, the current passes through the resistor. Accordingly, a voltage drop occurs, and a voltage difference is generated between the first lower fixing terminal310and the second lower fixing terminal320.

Because a voltage of the first lower fixing terminal310is the same as that of the first upper fixing terminal210and a voltage of the second lower fixing terminal320is the same as that of the second upper fixing terminal220, a voltage difference between the first upper fixing terminal210and the second upper fixing terminal220is the same as that between the first lower fixing terminal310and the second lower fixing terminal320.

FIG.5illustrates an operation state of a relay switch device in a pre-charge relay circuit mode,FIG.6is a circuit diagram in the pre-charge relay circuit mode ofFIG.5,FIG.7illustrates an operation state of a relay switch device in a main relay circuit mode, andFIG.8is a circuit diagram in the main relay circuit mode ofFIG.7.

Referring to these drawings, an operation example of the relay switch device according to an embodiment of the present disclosure will now be described in brief.

When a battery pack and a load are intended to be electrically connected to each other, first, the moving shaft410is lowered to make the resistive member430contact the first lower fixing terminal310and the second lower fixing terminal320.

Then, as shown in a current flow indicator line shown inFIG.5, a current flows from a (+) terminal of a battery pack to respective (+) terminals of a capacitor through the first upper fixing terminal210, the first metal wire610, the first lower fixing terminal310, the resistive member430, the second lower fixing terminal320, the second metal wire620and the second upper fixing terminal220in that order.

Therefore, according to the aforementioned configuration, as shown inFIG.6, a circuit equivalent to a conventional RC circuit provided by turning off a high potential main relay and turning on a pre-charge relay may be provided.

Then, when a predetermined time elapses and a pre-charge target voltage is reached, the moving shaft410is raised to make the contact plate420contact the first upper fixing terminal210and the second upper fixing terminal220.

Then, as shown in a current flow indicator line shown inFIG.7, a current flows from the (+) terminal of the battery pack to the respective (+) terminals of the capacitor through the first upper fixing terminal210, the contact plate420and the second upper fixing terminal220in that order.

Therefore, according to the aforementioned configuration, as shown inFIG.8, a circuit equivalent to a conventional circuit provided by turning off a pre-charge relay and turning on a high potential relay may be provided.

A thermoelectric device designed to have the same resistance value as a conventional pre-charge resistor may be employed as the resistive member430of the circuit mode switch module400.

The thermoelectric device may be a cooling thermoelectric device that performs thermoelectric cooling/heating inducing a temperature difference between one side and the other side or between one surface and the other surface by supplying electricity. Such a thermoelectric device may function as a resistor and may also reduce the temperature of the coil portion510.

For example, in the pre-charge circuit mode, as shown inFIG.5, the thermoelectric device may function as a resistor, and at this time, may be used to lower the internal temperature of the relay housing100by using supplied power as the operating power of the thermoelectric device.

The thermoelectric device may be attached to a lower portion of the contact plate420to be oriented in a lower direction of the relay housing100such that a cooling portion, namely, a heat absorbing side, faces the coil portion510. However, the heat absorbing side and a heat generating side may be changed by changing a current supply direction.

A necessary voltage for an operating voltage of the coil portion510tends to increase as the temperature increases. Therefore, when the temperature of the coil portion510is maintained low by using the cooling thermoelectric device as described above, problems such as incomplete contact of a contact that may be caused by an insufficient operating voltage of the coil portion510may be effectively prevented.

FIG.9schematically illustrates a structure of a relay switch device according to another embodiment of the present disclosure.

The relay switch device according to another embodiment of the present disclosure will now be described by referring toFIG.9.

Reference numerals ofFIG.9that are the same as those in the above-described embodiment denote the same members, and repeated descriptions of the same members will be omitted. Differences from the above-described embodiments will be mainly described.

When another embodiment of the present disclosure is compared with the above-described embodiment, the circuit mode switch module400includes the moving shaft410, the contact plate420, and a resistor700.

The moving shaft410and the contact plate420are the same as those in the above-described embodiment, but the resistor700is provided in at least one of the first metal wire610and the second metal wire620.

The relay switch device according to another embodiment of the present disclosure also enables switch between a pre-charge relay mode and a main relay mode, as in the above-described embodiment.

In other words, when the contact plate420descends and is attached to the first lower fixing terminal310and the second lower fixing terminal320, a current may flow from the first upper fixing terminal210to the second upper fixing terminal220via the resistor, and thus a pre-charge relay circuit mode may be provided.

When the contact plate420ascends and is attached to the first upper fixing terminal210and the second upper fixing terminal220, a current may flow from the first upper fixing terminal210to the second upper fixing terminal220without passing through the resistor700, and thus a main relay circuit mode may be provided.

As described above, one relay switch device according to the present disclosure may replace the roles of a conventional high-potential main relay, a conventional pre-charge relay, and a conventional pre-charge resistor. When such a relay switch device is mounted, a pre-charge relay and a pre-charge resistor, for example, may not be used, which may be advantageous in reducing the size of a BDU.

A BDU according to the present disclosure may include the above-described relay switch device. The BDU may include, in addition to the relay switch device, a low-potential main relay, a current sensor, a busbar or wire as an electrical connection means, and a BDU housing for accommodating them.

The BDU may be accommodated in a battery pack.

A battery pack according to the present disclosure may include battery modules composed of the BDU and a plurality of secondary batteries, a Battery Management System (BMS) for controlling charging and discharging of the battery modules, and a pack case for accommodating them.

Although embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the above-described embodiments, and various modifications can be made by anyone with ordinary skill in the art to which the disclosure pertains, without departing from the gist of the present disclosure claimed in the claims.

Meanwhile, although terms indicating directions such as up, down, left, and right are used in the present specification, these terms are only for convenience of description, and it is apparent to those skilled in the art that these terms may vary depending on a position of a target object or a position of an observer.