JP5577267B2 - Relay unit - Google Patents

Description

  The present invention relates to a relay unit including one or a plurality of relays that switch between energization and interruption of current by magnetic force in a unit casing.

  For example, a relay (electromagnetic relay) for switching between energization and interruption of current in a traveling circuit such as an electric vehicle or a hybrid vehicle is known (for example, see Patent Document 1). A circuit between the driving circuit such as an inverter in the vehicle and the battery as described above incorporates a plurality of relays together with a resistor or the like, and these are used as one relay unit mounted on the vehicle. Has been.

  The relay includes a fixed contact fixed in the relay casing and a movable contact that moves forward and backward with respect to the fixed contact by a magnetic force generated by energizing a built-in coil. And the contact part which consists of a fixed contact and a movable contact is accommodated in the contact chamber which is the closed space enclosed by the resin member in the relay housing | casing. By accommodating and arranging the contact portion in the contact chamber, a problem that an arc generated in the contact portion leaks to other parts to cause a short circuit is prevented.

JP 2001-176370 A

  However, in recent years, in order to improve the output of the vehicle, it is necessary to increase the voltage value and the current value of the current flowing through the traveling circuit. That is, the voltage value and current of the current to be interrupted by the relay tend to increase. In such a case, the arc energy generated at the contact portion when the current is interrupted by the relay is large, and the arc heat is increased. Due to the generation of this high-temperature arc, the internal pressure of the contact chamber rises rapidly.

  Therefore, if the volume of the contact chamber is reduced, the internal pressure of the contact chamber is likely to increase more rapidly. In some cases, the relay housing may be ruptured or deformed by the internal pressure, and the contact portion cannot be blocked (opened). It is thought that it becomes. Therefore, in order to avoid such a problem, the volume of the contact chamber needs to be increased to some extent, and as a result, it is difficult to reduce the size of the relay.

  On the other hand, in the relay unit, the component parts including the relay are arranged in the unit housing, but an area (space) where these component parts are not arranged is also formed due to the shape and wiring of the component parts. The Rukoto. Such a space is a so-called dead space.

  The present invention has been made in view of such problems, and intends to provide a relay unit that can sufficiently cope with a high breaking voltage and a high breaking current and can be easily reduced in size. Is.

A first invention is a relay unit including one or a plurality of relays that switch between energization and interruption of current by magnetic force in a unit housing,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and the contact chamber includes an opening that opens to the outside of the relay housing.
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer chamber communicates with the said contact chamber through the opening hole, Ri Na independent of space other than said contact chamber,
A plurality of the relays are arranged in the unit casing, and the unit casing is provided with the buffer chamber independent for each of the relays. Item 1).

The second invention is a relay unit comprising one or more relays in the unit housing for switching between energization and interruption of current by magnetic force,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and at least a part of a portion of the surrounding wall that surrounds the contact chamber that is a boundary with the outside of the relay housing is less rigid than the other portions. With low-rigidity walls,
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer chamber is in the relay unit, characterized in that together with the adjacent said contact chamber through said low rigid wall portion, comprising independently of the space other than said contact chamber (claim 2).
A third invention is a relay unit including one or a plurality of relays in a unit housing for switching between energization and interruption of current by magnetic force,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and the contact chamber includes an opening that opens to the outside of the relay housing.
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer chamber communicates with the contact chamber through the opening hole and is independent of a space other than the contact chamber.
The relay includes a plurality of the contact portions, and the unit housing includes the buffer chamber independent for each of the contact portions. ).

In the relay unit according to the first invention, the contact chamber communicates with the buffer chamber through the opening hole. Therefore, when an arc is generated when current is interrupted at the contact portion, an increase in the internal pressure of the contact chamber due to the heat of the arc can be mitigated. In other words, since the contact chamber communicates with the buffer chamber, even if the air in the contact chamber rapidly expands due to the heat of the arc, the pressure escapes to the buffer chamber, thereby reducing the increase in the internal pressure of the contact chamber. Can do. Even when the breaking voltage or breaking current is large and the arc energy is large, the increase in the internal pressure of the contact chamber can be mitigated as described above, so that the relay housing can be reliably damaged without causing damage or deformation. Current interruption can be performed.
Moreover, the temperature rise in the contact chamber can be mitigated, and insulation deterioration due to carbonization of the relay housing can be suppressed.

As a result, it is not necessary to increase the volume of the contact chamber, and the relay can be easily downsized. Accordingly, the relay unit can be easily downsized.
Further, since the buffer chamber is formed independently from a space other than the contact chamber, the arc does not leak and a short circuit is not caused. Further, moisture or the like does not enter from the outside into the contact chamber through the buffer chamber.

  Further, since the buffer chamber is formed in a part of the unit housing, it is not necessary to provide a part for forming the buffer chamber again. In particular, in a relay unit, a dead space is easily formed in the unit housing due to the shape and wiring of components including the relay. By providing the buffer chamber in the unit housing, it is possible to effectively use the dead space. As a result, the relay unit is not increased in size by providing the buffer chamber. On the other hand, since the relay can be easily downsized as described above, the relay unit as a whole can be easily downsized.

In the relay unit according to the second invention, the contact chamber is adjacent to the buffer chamber via the low-rigidity wall portion. Therefore, when an arc is generated when current is interrupted at the contact portion, an increase in the internal pressure of the contact chamber due to the heat of the arc can be mitigated. That is, since the contact chamber is adjacent to the buffer chamber through the low-rigidity wall portion, when the air in the contact chamber expands rapidly due to the heat of the arc, the low-rigidity wall portion is preferentially destroyed by the pressure. Thereby, the internal pressure of a contact chamber escapes to a buffer chamber, and the raise of the internal pressure of a contact chamber can be relieve | moderated. Even when the breaking voltage or breaking current is large and the arc energy is large, the increase in the internal pressure of the contact chamber can be mitigated as described above. And since the said low-rigidity wall part is destroyed preferentially as mentioned above, damage, a deformation | transformation, etc. of the other site | part in a relay housing | casing can be prevented, and an electric current interruption can be performed reliably.
Here, as a condition for destroying the low-rigidity wall portion, for example, an increase in the internal pressure of the contact chamber is required when a short circuit of a harness or the like occurs due to a vehicle collision accident or the like. When the normal ignition key is turned off and the small current is interrupted, the internal pressure of the contact chamber hardly increases, so that the low-rigidity wall portion is not destroyed.

Moreover, since the temperature rise in the contact chamber can be mitigated as described above, insulation deterioration due to carbonization of the relay housing can be suppressed.
As a result, it is not necessary to increase the volume of the contact chamber, and the relay can be easily downsized. Accordingly, the relay unit can be easily downsized.
Further, since the buffer chamber is formed independently from a space other than the contact chamber, the arc does not leak and a short circuit is not caused.

  Further, since the buffer chamber is formed in a part of the unit casing, the dead space in the unit casing can be used effectively, and the relay unit is not enlarged by providing the buffer chamber. . On the other hand, since the relay can be easily downsized as described above, the relay unit as a whole can be easily downsized.

  As described above, according to the present invention, it is possible to provide a relay unit that can sufficiently cope with a high cut-off voltage and a high cut-off current and can be easily reduced in size.

FIG. 3 is a cross-sectional explanatory view of the relay unit in the first embodiment, corresponding to a cross section taken along line AA in FIG. 2. BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 3 is a cross-sectional explanatory view of the relay unit in the first embodiment, corresponding to a cross section taken along line BB in FIG. 2. Sectional explanatory drawing of the relay by the plane orthogonal to the advancing / retreating direction of a movable contact in Example 1. FIG. The front explanatory drawing of the relay seen from the buffer room side in Example 1. FIG. Sectional explanatory drawing of the relay of an electricity supply state by the plane parallel to the advancing / retreating direction of a movable contact in Example 1. FIG. Sectional explanatory drawing of the relay of the interruption | blocking state by the plane parallel to the advancing / retreating direction of a movable contact in Example 1. FIG. FIG. 3 is an explanatory diagram of a power supply circuit in the first embodiment. Sectional explanatory drawing of the relay by the plane orthogonal to the advancing / retreating direction of a movable contact in Example 2. FIG. Sectional explanatory drawing of the relay unit in Example 3. FIG. Cross-sectional explanatory drawing of the relay by the plane orthogonal to the advancing / retreating direction of a movable contact in a comparative example. Explanatory drawing of the interruption | blocking waveform by the relay unit of Example 1 in an experiment example. Explanatory drawing of the interruption | blocking waveform at the time of using the relay of a comparative example in an experiment example.

In the first invention or the second invention, the relay unit may include a plurality of the relays or one relay unit. For example, when a plurality of relays are disposed in the unit housing, all of the relays may have the above-described configuration (the opening hole or the low-rigidity wall portion, etc.) The relay may include the above-described configuration (the opening hole or the low-rigidity wall portion).
Moreover, the said relay housing | casing and the said unit housing | casing can be comprised with resin, such as glass fiber reinforced polybutylene terephthalate (PBT), for example.

  In the relay unit according to the second aspect of the present invention, it is preferable that the low-rigidity wall portion is thinner than other portions of the surrounding wall. In this case, the low-rigidity wall can be easily formed.

  The low-rigidity wall portion may be realized by lowering the Young's modulus than other portions of the surrounding wall. In this case, the said low-rigidity wall part can be comprised reliably.

  Moreover, it is preferable that the said low-rigidity wall part consists of a cover part which block | closes the opening part provided in the said surrounding wall. In this case, the low-rigidity wall portion that is destroyed preferentially can be formed easily and reliably.

  The buffer chamber is preferably filled with an arc extinguishing agent for extinguishing an arc generated at the contact portion when the current is interrupted. In this case, when the low-rigidity wall portion is broken by the generation of an arc, the arc extinguishing agent filled in the buffer chamber flows into the contact chamber, and the arc can be effectively extinguished.

  The arc-extinguishing agent is preferably made of silica sand. In this case, the arc can be extinguished efficiently.

  Moreover, it is preferable that the said buffer chamber is arrange | positioned above the said contact part (Claim 8). In this case, when the low-rigidity wall portion is destroyed due to the generation of an arc, the arc-extinguishing agent falls from the buffer chamber to the contact portion, and thus the arc-extinguishing agent is efficiently supplied to the contact portion. The arc can be extinguished.

Further, the relay, the arc extinguishing magnetic body for extinguishing by stretching an arc generated in the contact portion during interruption of the current, it is preferable formed by arranging in the vicinity of the contact portion (claim 12) . In this case, the arc at the time of interruption can be effectively extinguished even if the interruption voltage and interruption current are high.

Moreover, it is preferable that the said buffer chamber is arrange | positioned with respect to the said contact chamber in the direction where the said arc is extended (Claim 1 3 ). In this case, since the pressure in the contact chamber can be released in the direction in which the arc energy spreads, the impact on the relay housing can be effectively reduced.

Further, the relay is configured to switch between energization and interruption of bidirectional currents having different sizes, and the buffer chamber has a larger current than the bidirectional current with respect to the contact chamber. it is preferable that the arc generated when the cut-off is arranged in the direction stretched (the claims 1 to 4). In this case, depending on the direction of the current to be interrupted, the direction in which the arc generated at the contact portion at the time of interruption is opposite and the size thereof is different, but the buffer chamber is located on the side where the larger arc is extended. Will be placed. As a result, it is possible to effectively mitigate the impact on the relay housing due to the arc energy.

  When the relay is configured to switch between energization and interruption of bidirectional current, the buffer chambers may be arranged in both directions of arc extension at the time of current interruption, and the buffer A chamber may be arranged. In the former case, the cut-off voltage and cut-off current can be increased in both directions. In the latter case, it is easy to reduce the size of the relay unit while effectively preventing damage to the relay housing.

In the relay unit according to the first aspect of the present invention , a plurality of the relays are arranged in the unit housing, and the unit housing includes the independent buffer chamber corresponding to each relay. Tei Ru. Thereby , it is possible to reliably prevent the arc generated at the contact portion of one relay from being conducted with the arc generated at the contact portion of another relay through the buffer chamber. As a result, a short circuit between a plurality of relays can be reliably prevented.

Further, the relay unit according to the third aspect, the relay is provided with a plurality of said contact portion, said unit housing, that provides the buffer chamber which is separate in response to each said contact portion . Thereby , it is possible to reliably prevent an arc generated in one contact portion from being electrically connected to an arc generated in another contact portion through the buffer chamber. As a result, it is possible to reliably prevent a short circuit between the plurality of contact portions.

Example 1
A relay unit according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the relay unit 1 of this example includes one or a plurality of relays 2 that switch between energization and interruption of current by magnetic force in a unit housing 3.

As shown in FIGS. 6 and 7, the relay 2 includes a solenoid unit 20 having a movable core 22 that advances and retreats by energization of the coil 21 and a contact unit 200 that opens and closes by the advance and retreat of the movable core 22. It is arranged in the body 23.
As shown in FIGS. 4 to 7, the relay housing 23 includes a contact chamber 28 that houses the contact portion 200, and the contact chamber 28 includes an opening hole 281 that opens to the outside of the relay housing 23. .

  As shown in FIGS. 1 and 3, the unit housing 3 includes a buffer chamber 31 formed adjacent to the contact chamber 28. The buffer chamber 31 communicates with the contact chamber 28 through the opening hole 281 and is independent from a space other than the contact chamber 28.

  As shown in FIG. 2, the relay unit 1 includes three relays 2, 101, a resistor 102, and a current sensor 103 in a unit housing 3 made of a resin such as glass fiber reinforced polybutylene terephthalate (PBT). Prepare. Of the three relays, two relays 2 are main relays 2a and 2b described later, and the other one relay 101 is a precharge relay described later.

As shown in FIG. 8, the relay unit 1 is used by being incorporated in a power supply circuit 5 for driving a traveling motor such as an electric vehicle or a hybrid vehicle.
The power supply circuit 5 is formed between a DC power supply 51 and a rotating electrical machine 52 that is a three-phase AC traveling motor, and includes a converter 53 for boosting the DC power supply 51 or reducing regenerative power, and DC power and AC power. And an inverter 54 for performing conversion. Relay unit 1 is wired between converter 53 and inverter 54 and DC power supply 51.

That is, the relays 2 are wired as main relays 2p and 2n in the current paths on the positive electrode side and the negative electrode side between the converter 53 and the inverter 54 and the DC power source 51, respectively. Further, a preliminary charging relay 101 connected in series with the resistor 102 is further connected in parallel with the main relay 2p provided in the current path on the positive electrode side. A current sensor 103 is connected between the negative side main relay 2n and the DC power source 51.
Further, a capacitor 55 is suspended between the positive current path and the negative current path.

  With the above configuration, the current supply between the DC power source 51 and the converter 53 and the inverter 54 is switched between energization and interruption. In the relays 2 and 101, there are a case where a current in the power running direction supplied from the DC power source 51 to the rotating electrical machine 52 flows, and a case where a current in the regeneration direction collected from the rotating electrical machine 52 to the DC power source 51 flows. . The current in the power running direction is larger than the current in the regeneration direction.

In the power supply circuit 5, the following operation is performed.
First, when the ignition key of the vehicle is turned on, the main relay 2p on the negative side and the preliminary charging relay 101 are turned on (energized state) in this order, and charging of the capacitor 55 is started. At this time, the resistor 102 is configured to limit the flow of a large inrush current to the power supply circuit 5 and gradually charge the capacitor 55.
After the capacitor 55 is charged, the positive-side main relay 2p is turned on, power supply to the rotating electrical machine 52 is started, and the preliminary charging relay 101 is turned off. During this time, a current in the power running direction flows through the relay 2 (main relays 2p, 2n).

In this state, the electric power collected in the rotating electrical machine 52 is regenerated to the DC power source 51 through the power supply circuit 5. That is, at this time, a current in the regeneration direction opposite to the power running direction flows through the relay 2 (main relays 2p, 2n).
When the ignition key is turned off, the two main relays 2p and 2n are turned off and the power supply in the power supply circuit 5 is cut off.

  Further, when an abnormality occurs in the rotating electrical machine 52, the converter 53, the inverter 54, or the like, the relay 2 (main relays 2p, 2n) is switched to the cut-off state, thereby cutting off the current and causing a large current to flow in the power supply circuit 5. Prevent it from continuing to flow.

Next, the configuration of the relay 2 (main relays 2p, 2n) will be described with reference to FIGS.
In the relay 2, various components including the contact portion 200 are arranged in a relay housing 23 made of a resin such as glass fiber reinforced polybutylene terephthalate (PBT).

  As shown in FIGS. 6 and 7, the relay 2 includes a fixed holder 24 that holds a pair of fixed contacts 241 fixed to the relay housing 23, and a pair of movable contacts 251 that are disposed to face the pair of fixed contacts 241. And a movable holder 25 that is held in a short-circuited state. As the movable holder 25 approaches or moves away from the fixed holder 24, the movable contact 251 comes into contact with or moves away from the fixed contact 241. That is, the contact portion 200 is configured by the fixed contact 241 and the movable contact 251.

The pair of movable contacts 251 are fixed by caulking near both ends of the movable holder 24 made of a metal plate so that the movable contacts 251 are short-circuited. Further, as shown in FIG. 4, one end of the fixed holder 24 is exposed to the outside of the relay housing 23 as an external terminal 242.
Moreover, the arc extinguishing magnet body 4 is embedded in the relay housing 23 by insert molding, press fitting, or the like. That is, the relay 2 is configured by disposing an arc extinguishing magnet body 265 for extending and extinguishing the arc 6 generated in the contact portion 200 when the current is interrupted, in the vicinity of the contact portion 200.

  Further, the pair of arc extinguishing magnet bodies 4 are arranged so that the opposing magnetic flux generation surfaces 40 have the same polarity. For example, the arc extinguishing magnet body 265 has the south pole facing the contact portion 200.

  As shown in FIGS. 6 and 7, the solenoid unit 20 in the relay 2 includes a coil 21 fixed to the relay housing 23 and a fixed core 27 made of a magnetic member, and a winding axis of the coil 21 with respect to the fixed core 27. And a movable core 22 that advances and retreats in the direction. The fixed core 27 and the movable core 22 are disposed inside the coil 21, and the movable core 22 is disposed on the movable holder 25 side of the fixed core 27.

  The movable core 22 is disposed on the movable holder 25 side of the plunger 221 made of a magnetic member that advances and retreats in the inner peripheral hole 210 of the coil 21 in the axial direction, the shaft 222 inserted and held by the plunger 221, and the plunger 222. And an insulator 223 formed of an insulating material such as a resin. The plunger 221, the shaft 222, and the insulator 223 are configured to be able to advance and retract integrally in the axial direction.

  The movable core 22 is urged toward the movable holder 25 by the core urging means 261 made of a coil spring. The core biasing means 261 is disposed in a state of being sandwiched between the fixed core 27 and the plunger 221.

  In addition, a yoke 262 and a plate 263 made of a magnetic material are provided around the coil 21, and a path of a magnetic flux generated by energizing the coil 21 is connected to the fixed core 27, the plunger 222, the plate 263, and the yoke 262. It is composed by.

Next, the operation of the relay 2 will be described in detail.
When the coil 21 is energized, a conductive state in which the pair of movable contacts 251 and the pair of fixed contacts 241 are in contact is formed as shown in FIG.

  That is, when the coil 21 is energized, a magnetic flux is generated around the coil 21, and a magnetic force is generated between the fixed core 27 and the movable core 22. This magnetic force is larger than the urging force applied to the core urging means 261. Therefore, the movable core 22 is attracted in the direction approaching the fixed core 27 by the magnetic force as shown in FIG. On the other hand, as shown in the figure, the core urging means 261 is pressed toward the coil 21 by the plunger 221 and contracts.

  The movable holder 25 is pressed toward the fixed holder 24 by a holder biasing means 264 made of a coil spring. Therefore, as shown in FIG. 7, the movable holder 25 that is in contact with the insulator 223 of the movable core 22 moves toward the fixed holder 24 along with the movable core 22, and the pair of movable contacts 251 and the pair of pairs are moved. It moves integrally to the position where the fixed contact 241 contacts.

  Even after the movable contact 251 and the fixed contact 241 come into contact with each other, the movable core 22 is attracted to the coil 21 as it is, so that the movable holder 25 and the movable core 22 are separated at this time. Thereafter, as shown in FIG. 6, the movable core 22 moves to a position where the lower end portion of the shaft 222 (end portion on the fixed core 27 side) contacts the fixed core 27 and stops at that position. At this time, the movable holder 25 is pressed toward the fixed holder 24 by the holder urging means 264, and the movable contact 251 and the fixed contact 241 are kept in contact with each other. And the state which the movable contact 251 and the fixed contact 241 contact | abutted with sufficient contact pressure is maintained, and a conduction | electrical_connection state is formed.

  In the conductive state, a current flowing from one end (external terminal 242) of one fixed holder 24 flows to the movable holder 25 through the contact portion 200 between the fixed contact 241 and the movable contact 251, and the other movable contact 251 is obtained. Flows to the other fixed holder 24 through the contact portion 200 between the fixed contact 241 and the fixed contact 241.

On the other hand, when the coil 21 is not energized, as shown in FIG. 7, a cut-off state is formed in which the movable contact 251 and the fixed contact 241 are not in contact.
In the shut-off state, the magnetic force generated by energizing the coil 21 disappears, so that the movable core 22 is pressed toward the movable holder 25 by the core urging means 261, contrary to the conductive state.

  That is, since the urging force of the core urging means 261 is larger than the urging force of the holder urging means 264, the movable holder 25 is pressed by the movable core 22 and moves away from the coil 21 together with the movable core 22. Move. Then, the movable holder 25 moves in a direction in which the pair of movable contacts 251 and the pair of fixed contacts 241 are separated from each other, so that an interrupted state in which the movable contact 251 and the fixed contact 241 are not in contact with each other is formed.

  Here, when shifting from the conductive state to the cut-off state, the arc 6 may be generated between the movable contact 251 and the fixed contact 241. As shown in FIG. 4, the arc 6 is stretched in a direction perpendicular to the advancing / retreating direction of the movable contact 251 in the contact chamber 28 by the arc extinguishing magnet 265 incorporated in the relay 2. In other words, the arc extinguishing amount magnet body 265 causes a Lorentz force to act on the arc 6 by generating a magnetic field in the vicinity of the contact portion 200, thereby extending the length of the arc 6. Thus, the arc 6 is extinguished by increasing the distance between the contacts along the arc 6.

  The direction in which the arc 6 is stretched by the direction in which the current flows in the contact portion 200 is opposite. The contact chamber 28 has an opening hole 281 in a direction in which the arc 6 generated when the current flowing during powering in the power supply circuit 5 is interrupted is extended. The opening hole 281 opens in a direction orthogonal to the longitudinal direction and the advancing / retreating direction of the movable holder 25. As shown in FIG. 5, the center of the opening hole 281 is formed at a position facing the contact portion 200.

  As shown in FIGS. 1 to 3, the relay unit 1 includes a plurality of relays 2 arranged in a unit housing 3. The unit housing 3 holds the components such as the relay 2 and is opposite to the housing body 30 made of resin in which the external terminals 242 of the relay 2 are embedded, with the relay 2 interposed therebetween. And a housing lid 300 disposed opposite to the side.

The unit housing 3 is formed with the buffer chamber 31 between the housing lid 300 and the relay 2. The buffer chamber 31 is disposed opposite to the opening hole 281 of the contact chamber 28 in the relay 2 and communicates with the contact chamber 28 through the opening hole 281.
As shown in FIG. 1, the buffer chamber 31 is disposed in a direction in which the arc 6 is extended with respect to the contact chamber 28. In particular, the relay 2 of the present example is configured to switch between energization and interruption of bidirectional currents having different sizes, and the buffer chamber 31 is more The arc 6 generated when interrupting a large current is arranged in a direction in which it is stretched. That is, in the power supply circuit 5, since the current during power running for driving the rotating electrical machine 52 is larger than the current during regeneration for recovering power from the rotating electrical machine 52, the current during power running is cut off. A buffer chamber 31 is formed on the side where the arc 6 generated in the contact portion 200 is extended.

The unit housing 3 includes independent buffer chambers 31 corresponding to the two contact portions 200 of the two relays 2. That is, each relay 2 includes two contact portions 200, and an opening hole 281 of the contact chamber 28 is formed so as to face each contact portion 200. These opening holes 281 are all open in the same direction, that is, toward the case lid 300 side of the unit case 3. In correspondence with each of the four contact portions 200 in total, one independent buffer chamber 31 is connected via each individual opening hole 281. Adjacent buffer chambers 31 are separated by partition walls 321 and 322. A partition wall 321 between two buffer chambers 31 corresponding to two contact portions 200 in one relay 2 is in contact with the relay housing 23. A partition 322 between the two buffer chambers 31 corresponding to the contact portions 200 of the two adjacent relays 2 is interposed between the relay housings 23 of the two relays 2. Further, the side walls 33 arranged at both ends in the arrangement direction in the four buffer chambers 31 are in contact with the side surfaces of the relay housing 23 of the relay 2, and the relay 2 is sandwiched between the partition walls 322. It has become.
The partition walls 321 and 322 and the side wall 33 are integrally formed as a part of the housing cover 300 in the unit housing 3.

Further, as shown in FIG. 3, the preliminary charging relay 101 is adjacent to the solenoid unit 20 side in the forward / backward direction of the movable contact 251 in one relay 2 (main relay 2 p) of the two relays 2. Has been placed. Here, the preliminary charging relay 101 protrudes toward the housing lid 300 from the relay 2 (main relay 2p). In other words, the surface of the relay 2 on the side of the housing lid 300 is retreated to the housing body 30 side of the preliminary charging relay 101, and the buffer chamber 31 is formed in the retreated space. ing.
The buffer chamber 31 is formed in a region that extends over substantially the entire length of the relay 2 in the advancing and retracting direction of the movable contact 251.

Next, the function and effect of this example will be described.
In the relay unit 1 of this example, as shown in FIGS. 1 and 3, the contact chamber 28 communicates with the buffer chamber 31 through the opening hole 281. Therefore, when the arc 6 is generated when the current is interrupted in the contact portion 200, an increase in the internal pressure of the contact chamber 28 due to the heat of the arc 6 can be reduced. That is, since the contact chamber 28 communicates with the buffer chamber 31, even if the air in the contact chamber 28 suddenly expands due to the heat of the arc 6, the pressure escapes to the buffer chamber 31, so that the contact chamber 28 The rise in internal pressure can be mitigated. Even when the breaking voltage or breaking current is large and the energy of the arc 6 is large, the increase in the internal pressure of the contact chamber 28 can be mitigated as described above, so that the relay housing 23 is not damaged or deformed. Therefore, the current can be surely interrupted. Moreover, the temperature rise in the contact chamber 28 can be mitigated, and insulation deterioration due to carbonization of the relay housing 23 can be suppressed.

As a result, it is not necessary to increase the volume of the contact chamber 28, and the relay 2 can be easily downsized. Accordingly, the relay unit 1 can be easily downsized.
Further, since the buffer chamber 31 is formed independently from a space other than the contact chamber 200, the arc 6 does not leak and a short circuit is not caused. Further, moisture or the like does not enter the contact chamber 28 through the buffer chamber 31 from the outside.

  Moreover, since the buffer chamber 31 is formed in a part of the unit housing 3, it is not necessary to provide a part or the like for forming the buffer chamber 31 again. In particular, in the relay unit 1, the configuration of the component parts including the relay 2 (the main relays 2 a and 2 b, the precharging relay 101, the register 102, the current sensor 103, etc.) in the unit housing 3 and the wiring relations. Moreover, a dead space is easily formed. By providing the buffer chamber 31 in the unit housing 3, the dead space can be effectively used.

For example, as illustrated in FIG. 3, the housing lid 300 side surface of the relay 2 is retracted toward the housing body 30 side from the preliminary charging relay 101, so that the housing lid with respect to the relay housing 23. The space that can be formed in the region on the part 300 side can be the above-described dead space. In this example, the dead space is effectively used by forming the buffer chamber 31 in this space.
As a result, the relay unit 1 is not increased in size by providing the buffer chamber 31. On the other hand, since the relay 2 can be easily downsized as described above, the relay unit 1 as a whole can be easily downsized.

  Further, as shown in FIG. 4, the relay 2 is configured by disposing an arc extinguishing magnet body 265 in the vicinity of the contact portion 200. Thereby, even when the breaking voltage and breaking current are high, the arc 6 at the time of breaking can be effectively extinguished. The buffer chamber 31 is arranged in a direction in which the arc 6 is extended with respect to the contact chamber 28. Thereby, since the pressure of the contact chamber 28 can be released in the direction in which the energy of the arc 6 spreads, the impact on the relay housing 23 can be effectively reduced.

  Further, the buffer chamber 31 extends in a direction in which the arc 6 generated when the larger current (current during power running) of the bidirectional current (power running direction and regenerative direction) is interrupted with respect to the contact chamber 28 is stretched. Has been placed. Thus, the buffer chamber 31 is arranged on the side where the larger arc 6 is stretched. As a result, the impact on the relay casing 23 caused by the energy of the arc 6 can be effectively reduced.

  Further, the unit housing 3 includes an independent buffer chamber 31 corresponding to each relay 2. Thereby, it is possible to reliably prevent the arc 6 generated in the contact portion 200 in one relay 2 from being electrically connected to the arc 6 generated in the contact portion 200 in the other relay 2 through the buffer chamber 31. As a result, a short circuit between the plurality of relays 2 can be reliably prevented.

  In addition, the unit housing 3 includes independent buffer chambers 31 corresponding to the respective contact portions 200. Thereby, it is possible to reliably prevent the arc 6 generated in one contact portion 200 from being electrically connected to the arc 6 generated in the other contact portion 28 through the buffer chamber 31. As a result, a short circuit between the plurality of contact parts 200 can be reliably prevented.

  As described above, according to this example, it is possible to provide a relay unit that can sufficiently cope with a high cut-off voltage and a high cut-off current and can be easily reduced in size.

(Example 2)
In this example, as shown in FIG. 9, instead of the opening hole 281 (see FIGS. 1 and 4) provided in the contact chamber 28 of the relay 2 in the relay unit 1 shown in the first embodiment, a low-rigidity wall portion 282 is provided. This is an example.
That is, the relay housing 23 has a low-rigidity wall portion 282 that is lower in rigidity than the other portions on at least a part of the surrounding wall 231 that surrounds the contact chamber 28 that is a boundary with the outside of the relay housing 23. I have. The buffer chamber 31 (see FIG. 1) is adjacent to the contact chamber 28 via the low-rigidity wall portion 282. Configurations other than the relay 2 such as the unit housing 3 are the same as those in the first embodiment.

The low-rigidity wall portion 282 is formed at the same position and region as the opening hole 281 in the first embodiment. However, the position and region are not particularly limited, and may be in a state of being interposed between the contact chamber 28 and the buffer chamber 31.
The low-rigidity wall portion 282 is thinner than other portions of the surrounding wall 231 of the relay housing 23. The thickness of the low-rigidity wall portion 282 can be, for example, half or less the thickness of the other portion of the surrounding wall 231, but is not particularly limited, and the internal pressure of the contact chamber 28 is increased by the energy of the arc 6. What is necessary is just the thickness of the grade which destroys preferentially with respect to the other site | part in the surrounding wall 231 when it raises rapidly.
Others are the same as in the first embodiment.

In the relay unit 1 of this example, the contact chamber 28 is adjacent to the buffer chamber 31 via the low-rigidity wall portion 282. Therefore, when the arc 6 is generated when the current is interrupted in the contact portion 200, an increase in the internal pressure of the contact chamber 28 due to the heat of the arc 6 can be reduced. That is, since the contact chamber 28 is adjacent to the buffer chamber 31 via the low-rigidity wall portion 282, when the air in the contact chamber 28 is rapidly expanded by the heat of the arc 6, the low-rigidity wall is preferentially caused by the pressure. Part 282 is destroyed. Thereby, the internal pressure of the contact chamber 28 escapes to the buffer chamber 31, and the increase in the internal pressure of the contact chamber 28 can be relieved. Even when the breaking voltage or breaking current is large and the energy of the arc 6 is large, the increase in the internal pressure of the contact chamber 28 can be mitigated as described above. Since the low-rigidity wall portion 282 is preferentially destroyed as described above, it is possible to prevent breakage, deformation, and the like of other parts in the relay housing 23, and to reliably cut off the current.
In addition, the same effects as those of the first embodiment are obtained.

  In the second embodiment, the example in which the low-rigidity wall portion 282 is configured by thinning a part of the surrounding wall 231 is shown. For example, a part of the surrounding wall 231 is made Young's modulus more than other parts. A low-rigidity wall portion can be formed by lowering the height. That is, the same effect as described above can be obtained by configuring the part with a material having a Young's modulus lower than that of other parts. For example, the other part is made of glass fiber reinforced polybutylene terephthalate (PBT), and the low-rigidity wall part is made of non-reinforced polyacetal (POM).

  In addition, a low-rigidity wall portion can be configured by providing an opening portion similar to the opening hole 281 shown in the first embodiment in a part of the surrounding wall 231 and covering the opening portion. In this case, it is conceivable that the lid is bonded to the relay housing 23 with an adhesive or the like. And when the internal pressure of the contact chamber 28 suddenly increases due to the energy of the arc 6, it is possible to ensure that the lid part is removed preferentially before other parts of the surrounding wall 231 are destroyed. The same effect can be obtained.

(Example 3)
This example is an example of the relay unit 1 in which the buffer chamber 31 is filled with the arc extinguishing agent 4 for extinguishing the arc 6 generated in the contact portion 200 when the current is interrupted, as shown in FIG.
The arc extinguishing agent 4 is made of silica sand. The buffer chamber 31 is disposed above the contact portion 200. In this example, as shown in FIG. 10, the buffer chamber 31 is disposed directly above the contact chamber 28 (directly above in the vertical direction). The contact chamber 28 and the buffer chamber 31 are adjacent to each other via the low-rigidity wall portion 282 of the contact chamber 28, and the buffer chamber 31 filled with the arc extinguishing agent 4 is formed above the low-rigidity wall portion 282. .
Others are the same as in the second embodiment.

  In the case of this example, when the low-rigidity wall portion 282 is broken by the generation of the arc 6, the arc extinguishing agent 4 filled in the buffer chamber 31 flows into the contact chamber, and the arc 6 is effectively extinguished. can do. Moreover, since the arc extinguishing agent 4 consists of silica sand, the arc 6 can be extinguished efficiently.

The buffer chamber 31 is disposed above the contact part 200. Thereby, when the low-rigidity wall portion 282 is broken by the generation of the arc 6, the arc-extinguishing agent 4 falls from the buffer chamber 31 to the contact portion 200. The arc 6 can be extinguished.
In addition, the same effects as those of the first embodiment are obtained.

  In addition, in this example, it is preferable that the formation position of the buffer chamber 31 is directly above the contact portion 200 in the vertical direction, but is not necessarily limited thereto. For example, the low-rigidity wall portion 282 has been destroyed, such as a configuration in which the low-rigidity wall portion 282 exists above the contact point portion 200 at a position off the vertical direction of the contact portion 200. In some cases, the arc extinguishing agent 4 can be infiltrated into the contact portion 200 to sufficiently exhibit its effect.

  Further, in the third embodiment, as described above, the posture of the relay unit 1 is specified so that the buffer chamber 31 is disposed above the contact chamber 28. However, in the first and second embodiments, the relay unit 1 is specified. The posture of 1 is not particularly specified, and the contact chamber 28 and the buffer chamber 31 can take various positional relationships.

(Comparative example)
This example is an example of the relay 9 in which the contact hole 28 is not provided with the opening hole 281 (see FIGS. 1 and 4) and the low-rigidity wall portion 282 (see FIG. 9), as shown in FIG. Others are the same as in the first embodiment. In FIG. 11, the same reference numerals are given to the same components as those in the relay 2 shown in the first embodiment.

  In the relay 9, when the arc 6 having large energy is generated at the contact portion 200 when the current is interrupted by the relay 9, the internal pressure of the contact chamber 28 is rapidly increased by the heat. Here, since the contact chamber 28 of the relay 9 is not provided with the opening hole 281 and the low-rigidity wall portion 282, there is no portion from which the internal pressure of the contact chamber 28 escapes. May cause deformation.

  In particular, when the volume of the contact chamber 28 is reduced with the miniaturization of the relay 9, the internal pressure of the contact chamber is likely to increase more rapidly, and the relay housing 23 is easily damaged or deformed. As a result, it is considered that the contact part 200 cannot be blocked (opened). Therefore, in order to avoid such a problem, it is necessary to increase the volume of the contact chamber 28 to some extent, and as a result, it is difficult to reduce the size of the relay 2.

(Experimental example)
In this example, as shown in FIGS. 12 and 13, the effect of current interruption by the relay unit 1 shown in the first embodiment is confirmed.
That is, in the power supply circuit 5 incorporating the relay unit 1, whether or not the current is reliably interrupted when the relay 2 is turned off from a state where a large current of the voltage value V0 and the current value I0 flows. This was confirmed by measuring the voltage between two points across the relay 2 and the current flowing through the relay 2.

  A test similar to this was performed by using the relay 9 in the relay unit 1 of Example 1 replaced with the relay 9 shown in the comparative example. However, in the test using the relay 9 of the comparative example, the value of the current passed through the power supply circuit was set to about 5/6 of I0, which was smaller than the test for the relay unit 1 of Example 1.

  The test result about the relay unit 1 of Example 1 is represented on the graph of FIG. 12, and the test result using the relay 9 of the comparative example is represented on the graph of FIG. 12 and 13, VE and VC are measurement voltages, and IE and IC are measurement currents. In each graph, the vertical axis represents voltage or current, and the horizontal axis represents time. Then, the time 0 (vertical line L) is the time when the contact point 200 in the relay is physically separated (the time when an OFF signal is given to the relay).

  As can be seen from the graph of FIG. 12, in the relay unit 1 of the first embodiment, the measured current IE suddenly decreases to zero after the contact point 200 is opened (time 0), and the measured voltage VE jumps up. This has shown that the relay unit 1 of Example 1 interrupted | blocked the electric current reliably. Then, the measured voltage VE after the interruption coincides with the voltage value V0 applied to the power supply circuit. Further, the time from the time 0 until the measured current IE becomes 0, that is, the time until the arc 6 is extinguished (breaking time T) was 4 ms or less.

  On the other hand, as can be seen from the graph of FIG. 13, when the relay 9 of the comparative example is used, the measurement current IC decreases and the measurement voltage VC also increases from the time (time 0) when the contact portion 200 is opened. However, the measurement current IC does not become zero, and the measurement voltage VC does not rise to the applied voltage value V0.

This means that after the contact part 200 in the relay is physically separated, the arc 6 continues to be generated and the arc 6 does not break. And as the cause, the relay housing | casing 23 was partially destroyed or deform | transformed by the internal pressure rise and arc heat of the contact chamber 28, and the distance of the fixed contact 241 and the movable contact 251 in the contact part 200 became short. Conceivable.
It is also considered that the electrical resistance is reduced due to carbonization of the inner wall surface of the relay housing 23 due to a rapid temperature rise in the contact chamber 28. In other words, the resistance per unit length of the arc extending along the inner wall of the carbonized relay housing 23 is reduced, and a larger space than the contact chamber 28 is required for current interruption, which may also cause interruption. Conceivable.
Furthermore, it is considered that the atmospheric temperature in the contact chamber 28 is increased due to the increase in the internal pressure of the contact chamber, and the dielectric breakdown voltage of air is greatly reduced. That is, an arc extension in which the arc-shaped arc that has once extended is shortened by short-circuiting between the fixed contact 241 and the movable contact 251 or between the portions in the arc-shaped arc due to a decrease in the dielectric breakdown voltage of the air in the contact chamber. This may be due to the fact that the arc is difficult to break.

  From the above results, the relay unit 1 of Example 1 sufficiently responds to the high cutoff voltage and high cutoff current that could not be interrupted when the relay 9 of the comparative example was used, and the current interruption was ensured. It was confirmed that

DESCRIPTION OF SYMBOLS 1 Relay unit 2 Relay 20 Solenoid part 200 Contact part 21 Coil 22 Movable core 23 Relay housing | casing 28 Contact chamber 281 Open hole 282 Low-rigidity wall part 3 Unit housing | casing 31 Buffer chamber

Claims (14)

A relay unit having one or more relays for switching between energization and interruption of current by magnetic force in a unit housing,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and the contact chamber includes an opening that opens to the outside of the relay housing.
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer chamber communicates with the said contact chamber through the opening hole, Ri Na independent of space other than said contact chamber,
A plurality of the relays are arranged in the unit casing, and the unit casing includes the independent buffer chamber corresponding to each relay. A relay unit having one or more relays for switching between energization and interruption of current by magnetic force in a unit housing,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and at least a part of a portion of the surrounding wall that surrounds the contact chamber that is a boundary with the outside of the relay housing is less rigid than the other portions. With low-rigidity walls,
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer unit is adjacent to the contact chamber through the low-rigidity wall portion, and is independent of a space other than the contact chamber.   The relay unit according to claim 2, wherein the low-rigidity wall portion is thinner than other portions of the surrounding wall.   The relay unit according to claim 2, wherein the low-rigidity wall portion has a Young's modulus lower than that of other portions of the surrounding wall.   The relay unit according to claim 2, wherein the low-rigidity wall portion includes a lid portion that closes an opening provided in the surrounding wall.   The relay unit according to any one of claims 2 to 5, wherein the buffer chamber is filled with an arc extinguishing agent for extinguishing an arc generated in the contact portion when the current is interrupted. Relay unit to be used.   The relay unit according to claim 6, wherein the arc-extinguishing agent is made of silica sand.   The relay unit according to claim 6 or 7, wherein the buffer chamber is disposed above the contact portion. A relay unit having one or more relays for switching between energization and interruption of current by magnetic force in a unit housing,
At least one of the relays includes a solenoid portion having a movable core that moves forward and backward by energization of the coil, and a contact portion that opens and closes when the movable core moves forward and backward. The housing includes a contact chamber that accommodates the contact portion, and the contact chamber includes an opening that opens to the outside of the relay housing.
The unit housing includes a buffer chamber formed adjacent to the contact chamber,
The buffer chamber communicates with the contact chamber through the opening hole and is independent of a space other than the contact chamber.
The relay includes a plurality of contact portions, and the unit housing includes the independent buffer chamber corresponding to each contact portion . The relay unit according to any one of claims 2 to 9, wherein a plurality of the relays are arranged in the unit casing, and the unit casing is independent for each of the relays. A relay unit comprising a buffer chamber . The relay unit according to any one of claims 2 to 8, wherein the relay includes a plurality of the contact portions, and the unit housing is independent for each of the contact portions. relay unit, characterized in that it comprises a. The relay unit according to any one of claims 1 to 11, wherein the relay includes an arc-extinguishing magnet body for extending and extinguishing an arc generated in the contact portion when the current is interrupted. A relay unit that is arranged in the vicinity of . 13. The relay unit according to claim 12, wherein the buffer chamber is disposed in a direction in which the arc is extended with respect to the contact chamber .   The relay unit according to claim 13, wherein the relay is configured to switch energization and interruption of bidirectional currents having mutually different sizes, and the buffer chamber is configured to switch the bidirectional chamber with respect to the contact chamber. The relay unit is arranged in a direction in which an arc generated when a larger current is interrupted is extended.

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