JP2023113059A - Electric connection box for vehicle - Google Patents

Abstract

To secure normal operation by suppressing an influence due to dew condensation or freezing even in the case where a vehicle is used in an environment such as a cold district.SOLUTION: In an electric connection box 10, two type of relays such as PCB relay modules 12 and 13 or plug-in relays 14 to 17 are mounted. A power source supply to a load of an engine start system on-vehicle device 31 that requires a countermeasure on dew drop and freezing is controlled by the PCB relay module 12. In a circumference of an electric coil as a heat source in the PCB relay module 12, since a change of a heat distribution becomes looseness, normal operation can be secured because the dew drop hardly occurs even in the case of high humidity. In the load that the countermeasure on the dew drop is not important, the power source supply is controlled by using the plug-in relay or the like.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electric junction box for vehicles.

In various vehicles, electric connection boxes are used to distribute the power supply power output from the main power supply, such as the vehicle battery and alternator (generator), and supply it to various vehicle equipment connected as loads on the downstream side. is often used. In addition, such an electric connection box often includes a relay for switching on/off the power supply for each load system, and a fuse for interrupting power supply in the event of an abnormality.

For example, Patent Literature 1 discloses an electrical junction box that provides an inexpensive electrical junction box with an integrated electronic control unit. The electrical connection box body of Patent Document 1 has a plug-in relay and a fuse housing for inserting a fuse on the base cover. Further, it is disclosed that a power distribution bus bar connected to the power supply side is provided inside the base cover.

Further, Patent Document 2 discloses an electrical connection box that enables flexible correspondence according to the specifications of the vehicle in which it is mounted. In the relay box of Patent Document 2, both a relay block to which a plug-in relay can be attached and a relay module in which a circuit structure having a switching element mounted thereon is accommodated in a module case can be attached to the same mounting portion. It is As a result, high-grade cars will be equipped with relay modules with high functionality and high relay mounting density, and low-grade cars will be equipped with relay blocks that have a lower relay mounting density but are cheaper than relay modules. This makes it easier to distinguish between relay modules and relay blocks according to differences in specifications.

Further, Patent Document 3 discloses a technique for simplifying the configuration of an electrical junction box having circuit units. Furthermore, mounting mechanical relays and plug-in relays on electrical junction boxes is disclosed.

JP 2007-97321 A JP 2011-19375 A JP 2013-123342 A

By the way, an electric junction box for a vehicle is usually installed in an engine room or the like, so the electric parts inside the electric junction box are used in an environment where temperature and humidity change drastically. Therefore, it is conceivable that dew condensation may occur inside the relays arranged inside the electric connection box, or the moisture generated by the dew condensation may freeze as the outside temperature drops.

If dew condensation or freezing occurs in the relays of the electric connection box, it is possible that the relays will not operate until the frozen state of the electrical contacts is resolved, so it is necessary to take countermeasures.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric connection box for a vehicle that can ensure normal operation even when the vehicle is used in an environment such as a cold region. That's what it is.

The above objects of the present invention are achieved by the following configurations.

Equipped with a plurality of relays that are arranged in a circuit that distributes the power supply power supplied from the upstream side of the on-board power supply and supplies it to the downstream load side, and that performs opening and closing operations of electrical contacts according to control signals,
wherein the plurality of relays includes a first relay and a second relay having different characteristics of susceptibility to condensation;
The first relay is composed of a relay module in which a plurality of electric coils are arranged side by side on one circuit board, and is arranged at least in part of a place where dew condensation is likely to occur.
Electrical connection box for vehicles.

According to the electric junction box for a vehicle of the present invention, even when the vehicle is used in an environment such as a cold region, it is possible to suppress the occurrence of dew condensation and freezing of water in the relay, so that the relay can be operated normally. can be guaranteed.

The present invention has been briefly described above. Furthermore, the details of the present invention will be further clarified by reading the following detailed description of the invention (hereinafter referred to as "embodiment") with reference to the accompanying drawings. .

FIG. 1 is a block diagram showing the configuration of a vehicle electric connection box according to an embodiment of the present invention. FIG. 2 is an electric circuit diagram showing a configuration example of one PCB relay module. FIG. 3 is an electrical circuit diagram showing a modification of one PCB relay module. FIG. 4 is a front view showing a plug-in relay and a connector section; FIG. 5 is a front view showing a state in which the plug-in relay is attached to the connector. FIG. 6 is a front view showing the PCB relay module and connector section. FIG. 7 is a front view showing a state in which the PCB relay module is attached to the connector. FIG. 8 is a schematic diagram showing an example of heat distribution in the operating state of the plug-in relay. FIG. 9 is a schematic diagram showing an example of heat distribution in the operating state of the PCB relay module. FIG. 10 is a plan view showing an example of the layout of relays in the electrical connection box.

Specific embodiments relating to the present invention will be described below with reference to each drawing.

FIG. 1 is a block diagram showing the configuration of a vehicle electric connection box (electrical connection box 10) according to an embodiment of the present invention.
The electrical connection box 10 shown in FIG. 1 is used to distribute the power of the power supply on the vehicle to each system and supply it to various loads.

An upstream power supply terminal 10 a of the electrical connection box 10 is connected to a positive terminal 21 a of a vehicle battery 21 via a power supply line 22 . A negative terminal 21 b of the vehicle battery 21 is connected to the ground 20 .

In the example shown in FIG. 1, the downstream side power supply terminals 10b, 10c, 10d, 10e, 10f, and 10g of the electric connection box 10 are connected to the engine starting vehicle-mounted device 31, the safety vehicle-mounted device 32, and the general vehicle-mounted device, respectively. 33, 34, 35 and 36 are connected.

The engine-starting vehicle-mounted device 31 is a system electrical component related to starting the engine, such as a starting starter and an ignition circuit. In addition, the safety system vehicle-mounted device 32 in FIG. 1 is an electrical component in a portion that requires countermeasures against dew condensation and freezing, among the electrical components that are important in ensuring the safety of the vehicle.

The general on-vehicle devices 33 to 36 are electrical components belonging to systems other than the engine start on-board device 31 and the safety on-board device 32, such as horns, headlights, brake lamps, wipers, various electronic control units (ECUs), It corresponds to various indoor equipment.

In the example shown in FIG. 1, a fuse 11, PCB relay modules 12 and 13, plug-in relays 14, 15, 16 and 17, and a control section 18 are provided inside the electric connection box 10. FIG. Of course, the number of fuses, the number of PCB relay modules, the number of plug-in relays, etc. contained in the electric connection box 10 can be increased or decreased as required.

The PCB relay module 12 can control power supply from the power line 23 to the power line 24 by internal electrical contacts that are turned on and off according to the control signal SG1. The PCB relay module 13 can control power supply from the power line 23 to the power line 25 by internal electrical contacts that are turned on and off according to the control signal SG2.

The plug-in relays 14 to 17 can control power supply from the power line 23 to the power lines 26 to 29 by internal electrical contacts that are turned on and off according to SG3 to SG6, respectively.
The plug-in relays 14-17 comprise a relatively large single electrical coil and one or more electrical contacts. By energizing/de-energizing the electric coil, the movable portion moves, and the open/closed state of the electric contact is switched. In general, plug-in relays have a slow reaction speed, high durability, and can carry a relatively large amount of current through their electrical contacts. Also, the electric coil in the plug-in relay has a relatively small resistance value, so a large current flows. The plug-in relays 14 to 17 can be easily attached and detached one by one using connectors.

On the other hand, each of the PCB relay modules 12 and 13 includes a plurality of relatively small electric coils (for example, 6, 8, etc.) mounted on a circuit board (PCB) and a plurality of electric contacts that can be opened and closed for each coil. It has By using connectors, the PCB relay modules 12 and 13 can be attached and detached in module units. In general, PCB relay modules can be arranged in high density due to the small size of each circuit. Also, each electrical coil in the PCB relay module has a relatively high resistance and therefore draws relatively little current.

The control unit 18 switches the states of the control signals SG1 to SG6 depending on the situation, and switches the PCB relay modules 12 and 13 and the plug-in relays 14 to 17 on and off.

For example, when the ignition of the vehicle is turned on, the electrical contacts in the PCB relay module 12 are closed by the control signal SG1 output by the control unit 18, and the power from the vehicle battery 21 is transferred to the power lines 22, 23 and the PCB relays. The power is supplied to the engine-starting in-vehicle device 31 via the module 12, the power line 24, and the downstream power terminal 10b. Therefore, the engine can be started.

FIG. 2 is an electric circuit diagram showing a configuration example of one PCB relay module 12. As shown in FIG.
The PCB relay module 12 shown in FIG. 2 includes a driver 45, six electrical coils C1-C6, and six electrical contacts SW1-SW6. These components are located on a common circuit board.

The open/close state of each of the electric contacts SW1 to SW6 is switched by energization/non-energization of the electric coils C1 to C6. The driver 45 switches energization/non-energization of the electric coils C1 to C6 according to the control signal SG1.

In the PCB relay module 12 shown in FIG. 2, one terminal of each of the electrical contacts SW1 to SW6 is commonly connected to the power supply line 23. As shown in FIG. The other terminals of the electrical contacts SW1 to SW6 are connected in common to the power supply line 24. As shown in FIG. That is, the six electrical contacts SW1-SW6 in this module are connected in parallel.

Even if the allowable current of each of the electrical contacts SW1 to SW6 is relatively small, a relatively large current can flow through the power supply lines 23 and 24 by connecting the electrical contacts SW1 to SW6 in parallel.

Further, when each of the electrical contacts SW1 to SW6 is small, it is possible to downsize each of the electrical coils C1 to C6, and it is also possible to reduce the current flowing through the electrical coils C1 to C6.

FIG. 3 is an electrical circuit diagram showing a modification of one PCB relay module.

The PCB relay module 12A shown in FIG. 3 includes a driver 45, six electrical coils C1-C6, and six electrical contacts SW1-SW6. These components are located on a common circuit board.

The open/close state of each of the electric contacts SW1 to SW6 is switched by energization/non-energization of the electric coils C1 to C6. A driver 45 shown in FIG. 3 switches energization/non-energization of the electric coils C1 to C6 in accordance with control signals SG1 and SG2.

In the PCB relay module 12A shown in FIG. 3, one terminal of each of the electrical contacts SW1 to SW3 is commonly connected to the power supply line 23, and the other terminal of each of the electrical contacts SW1 to SW3 is commonly connected to the power supply line 24. It is connected to the. One terminal of each of the electrical contacts SW4 to SW6 is commonly connected to the power supply line 23, and the other terminal of each of the electrical contacts SW4 to SW6 is commonly connected to the power supply line 25. FIG.

That is, within this module, the three electrical contacts SW1-SW3 are connected in parallel with each other, and the three electrical contacts SW4-SW6 are also connected in parallel with each other.
A single PCB relay module 12A shown in FIG. 3 can be used in place of the two PCB relay modules 12, 13 in FIG.

4 is a front view showing the plug-in relay 14 and the connector section 40. FIG. FIG. 5 is a front view showing a state where the plug-in relay 14 is attached to the connector portion 40. FIG.

The plug-in relay 14 shown in FIG. 4 has a relatively large coil portion 14a in the central portion, and electrodes 14b and 14c connected to the upper and lower ends of the coil portion 14a. It also has a contact portion 14d which is mechanically moved by energization/non-energization of the coil of the coil portion 14a. Further, a plurality of relay terminal portions 14e are arranged on the lower end side of the plug-in relay 14 so as to protrude therefrom. The plug-in relay 14 also has a case 14f made of resin or the like, which covers the coil portion 14a, the electrodes 14b and 14c, and the like.

On the other hand, the connector portion 40 arranged on the housing of the electrical connection box 10 has a connector case 40a and a plurality of female terminals 40b, and the female terminals 40b are connected to electric wires 40c. The connector case 40a is made of resin, for example. The electric wire 40c has a relatively thick core so as to allow passage of a large current. Also, a bus bar may be used instead of the electric wire 40c.

The relay terminal portion 14e of the plug-in relay 14 is inserted and fitted inside each female terminal 40b. That is, the plug-in relay 14 is attached to the connector portion 40 as shown in FIG.

6 is a front view showing the PCB relay module 12 and the connector section 41. FIG. 7 is a front view showing a state in which the PCB relay module 12 is attached to the connector portion 41. FIG.

A PCB relay module 12 shown in FIG. 6 has a relatively small coil portion 12a near the center of the drawing, and electrodes 12b and 12c electrically connected to the ends of the coil portion 12a. Further, it has a contact portion 12e which is mechanically moved by energization/non-energization of the coil of the coil portion 12a.

Although only one coil portion 12a is shown inside the PCB relay module 12 in FIG. 6, a plurality of (for example, six) coil portions 12a are actually arranged. Moreover, the coil part 12a is mounted on the circuit board 12d.

The circuit board 12d has a foil-like conductor pattern formed over one side, both sides, or multiple layers of a resin board, like a general printed circuit board. Each terminal of the coil portion 12a and each terminal of the electrodes 12b and 12c are fixed on the circuit board 12d and electrically connected to the conductor pattern on the circuit board 12d by soldering or the like.

A plurality of coil portions 12a on the circuit board 12d are each covered with a case 12i. Further, the outside of the entire module is covered with a module case 12g made of resin or the like.

The circuit board 12d is fixed to the module base 12h. A plurality of board connection terminals 12f made of metal are connected to the circuit board 12d. Each board connection terminal 12f is formed in an L shape, one end of which is connected to the conductor pattern on the circuit board 12d, and the other end of which protrudes from the inside of the module base 12h.

On the other hand, the connector portion 41 arranged on the housing of the electric connection box 10 has a connector case that can be fitted with the module base portion 12h, and a plurality of female terminals 41a fixed to the connector case. An electric wire 41b is connected to the terminal 41a. The connector case is made of resin, for example. The electric wire 41b has a relatively thick core so as to allow passage of a large current. Also, a bus bar may be used instead of the electric wire 41b.

By fitting the module base portion 12h of the PCB relay module 12 to the connector portion 41, the PCB relay module 12 can be integrated and mounted on the electric connection box 10 as shown in FIG.

FIG. 8 is a schematic diagram showing an example of heat distribution in the operating state of the plug-in relay 14. As shown in FIG. FIG. 9 is a schematic diagram showing an example of heat distribution in the operating state of the PCB relay module 12. As shown in FIG.

In the case of the plug-in relay 14, the coil is large, the electric resistance is small, and the amount of heat generated in the coil is large. On the other hand, electrodes 14b, 14c, etc. with low thermal resistance are located in the vicinity of the heat-generating coil, and a female terminal 40b, electric wire 40c (or bus bar), etc., with high thermal capacity are connected to the electrodes 14b, 14c. Therefore, the peripheral portion of the heat-generating coil is easily cooled by good heat conduction. Therefore, only the coil portion has a locally high temperature, and the peripheral portion has a low temperature.

FIG. 8 shows an example of the result of measuring the state of temperature distribution in the relay inner area AX of the plug-in relay 14 . A region of interest A1 in FIG. 8 indicates the coil of the plug-in relay 14 and its neighboring region. As shown in FIG. 8, it can be seen that a slight difference in position causes a large temperature difference in the attention area A1 of the plug-in relay 14 .

On the other hand, in the case of the PCB relay module 12, each coil is relatively small, the electrical resistance is large, and the amount of heat generated in each coil is small. The electrodes 12b, 12c, etc. connected to the heat-generating coils are connected to the conductor pattern on the circuit board 12d as shown in FIG. It is connected.

Therefore, the amount of heat generated by each coil in the PCB relay module 12 is small, and the heat generated by each coil moves so as to diffuse over the entire circuit board 12d, so that the heat distribution is difficult to concentrate. Moreover, since the circuit board 12d has a higher thermal resistance than metal such as terminals, the periphery of the coil is difficult to cool. Therefore, the temperature of the coil portion does not rise so much, and the temperature drop around the coil is moderate.

FIG. 9 shows an example of the result of measuring the temperature distribution in the relay inner area AY of the PCB relay module 12 . A region of interest A2 in FIG. 9 shows one coil in the PCB relay module 12 and its neighboring region. As shown in FIG. 9, it can be seen that the distribution of the temperature difference is moderate in the attention area A2 of the PCB relay module 12 .

When a large local temperature difference occurs as in the region of interest A1 in FIG. 8, moisture in the air tends to condense in that portion. Furthermore, when the temperature in the air drops, water droplets and the like caused by dew condensation freeze on various parts of the plug-in relay 14, which may cause malfunction of the relay and contact failure of electrical contacts.

On the other hand, in the case where the temperature change due to the difference in position is gentle as in the attention area A2 in FIG. 9, the humidity in the air is high and dew condensation is unlikely to occur even when the temperature drops. Therefore, even if the temperature drops further, malfunction of the PCB relay module 12 and contact failure of electrical contacts due to freezing are less likely to occur.

FIG. 10 is a plan view showing an example of the layout of relays in the electrical connection box.
One PCB relay module 12A and six plug-in relays (14 to 17) are mounted inside the housing of the electrical connection box 10A shown in FIG.

As described above, the electrical connection box 10 shown in FIG. 1 employs the PCB relay modules 12 and 13, and dew condensation and freezing are unlikely to occur at these portions. For example, in conditions such as winter when the temperature is low and the humidity is high, condensation and freezing are likely to occur. Since dew condensation and freezing are unlikely to occur, the power supply to the engine start system on-vehicle device 31 can be ensured, and the engine can be reliably started.

In addition, since the electric connection box 10 in FIG. 1 controls the power supply to the safety system on-board equipment 32 using the PCB relay module 13, the safety system on-board equipment 32 can also be protected against condensation and freezing. .

In addition, the electric junction box 10 of FIG. 1 controls power supply using plug-in relays 14 to 17 for general onboard devices 33 to 36 other than the engine starting onboard device 31 and the safety onboard device 32. So you can take advantage of plug-in relays. That is, since the plug-in relays 14 to 17 are highly durable and have the characteristics of allowing opening and closing of relatively large currents, they can be used with electrical components such as horns, which may be frequently turned on and off. It is preferable to employ it in a portion that controls the power supply to the load circuit that includes it. In addition, since the plug-in relays 14 to 17 can be attached and detached individually for each coil and for each contact with a connector, it is preferable to use them for supplying electric power to electrical equipment installed as optional equipment in high-grade vehicle models, for example.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified, improved, etc. as appropriate. In addition, the material, shape, size, number, location, etc. of each component in the above-described embodiment are arbitrary and not limited as long as the present invention can be achieved.

Here, the features of the electrical junction box for vehicles according to the embodiments of the present invention described above are summarized and listed briefly in [1] to [5] below.
[1] A plurality of relays arranged in a circuit for distributing power supply power supplied from the upstream side of an on-vehicle power supply and supplying it to the downstream load side, and performing opening and closing operations of electrical contacts according to control signals,
The plurality of relays include first relays (PCB relay modules 12 and 13) and second relays (plug-in relays 14 to 17) having different characteristics of dew condensation susceptibility,
The first relay is composed of a relay module (PCB relay module 12) in which a plurality of electric coils (C1 to C6) are arranged side by side on a single circuit board (12d), and at least one portion where dew condensation is likely to occur. placed in the
Electrical connection box for vehicle (electrical connection box 10).

According to the electrical connection box for a vehicle having the configuration [1] above, the first relay has a characteristic that condensation and freezing are less likely to occur than the second relay, so that the first relay can function normally even in cold regions. functions can be guaranteed. Moreover, by adopting both the first relay and the second relay, it is possible to optimize the configuration according to the application of each load.

[2] At least one of the relay modules (PCB relay modules 12, 12A) is connected to a circuit for controlling the power supply of a circuit for starting the vehicle engine (in-vehicle device 31 for starting the engine).
The electric junction box for vehicles according to the above [1].

According to the electrical connection box for vehicle having the configuration [2], condensation and freezing of the relay contacts can be suppressed and the engine can be reliably started even in cold regions.

[3] At least one of the relay modules (PCB relay module 13) is connected to a circuit for controlling power supply to a device (safety-related in-vehicle device 32) necessary for ensuring safety in the vehicle.
The electrical junction box for vehicles according to the above [1] or [2].

According to the electrical junction box for vehicles having the configuration [3] above, it is possible to suppress the occurrence of dew condensation and freezing on the relay contacts even in cold regions, and to ensure the normal operation of important electrical components. .

[4] The relay module has a connection terminal (board connection terminal 12f) for connecting a circuit on the circuit board (12d) and an external circuit,
The electric junction box for vehicles according to the above [1].

According to the electric junction box for vehicles having the configuration of [4] above, even when a circuit component with a large heat capacity such as a thick electric wire or a bus bar is connected to the tip of the connection terminal, the circuit is difficult to radiate heat from each coil, which is a heat source. Since heat is dissipated through the substrate and connection terminals, heat dissipation is suppressed and abrupt changes in heat distribution are also suppressed. As a result, the effect of preventing the occurrence of dew condensation and freezing of water is obtained.

[5] The relay module has a cover (module case 12g) arranged to cover the plurality of electric coils and electric contacts inside the relay module.
The vehicle electrical connection box according to any one of [1] to [4] above.

According to the electrical connection box for a vehicle having the above configuration [5], the cover can suppress the circulation of air in the vicinity of the electrical coils in the relay module. It becomes possible to homogenize the distribution. This facilitates the prevention of condensation and freezing.

REFERENCE SIGNS LIST 10 electric connection box 10a upstream power supply terminal 10b, 10c, 10d, 10e, 10f, 10g downstream power supply terminal 11 fuse 12, 12A, 13 PCB relay module 12a coil section 12b, 12c electrode 12d circuit board 12e contact section 12f board connection Terminal 12g Module case 12h Module base 12i Case 14, 15, 16, 17 Plug-in relay 14a Coil part 14b, 14c Electrode 14d Contact part 14e Relay terminal part 14f Case 18 Control part 20 Ground 21 Vehicle battery 21a Positive terminal 21b Negative electrode Terminals 22, 23, 24, 25, 26, 27, 28, 29 Power supply line 31 Engine starting system vehicle-mounted device 32 Safety system vehicle-mounted device 33, 34, 35, 36 General system vehicle-mounted device 40, 41 Connector part 40a Connector case 40b, 41a Female side terminal 40c, 41b Electric wire 45 Driver A1, A2 Attention area AX, AY Relay inner area C1, C2, C3, C4, C5, C6 Electric coil SG1 to SG6 Control signal SW1 to SW6 Electric contact

Claims (5)

Equipped with a plurality of relays that are arranged in a circuit that distributes the power supply power supplied from the upstream side of the on-board power supply and supplies it to the downstream load side, and that performs opening and closing operations of electrical contacts according to control signals,
wherein the plurality of relays includes a first relay and a second relay having different characteristics of susceptibility to condensation;
The first relay is composed of a relay module in which a plurality of electric coils are arranged side by side on one circuit board, and is arranged at least in part of a place where dew condensation is likely to occur.
Electrical connection box for vehicles. at least one said relay module is connected to a circuit for controlling the power supply of a circuit for engine starting of the vehicle;
The electric connection box for vehicles according to claim 1. At least one of the relay modules is connected to a circuit that controls the power supply to safety equipment in the vehicle.
The electric connection box for vehicles according to claim 1 or 2. The relay module has a connection terminal that connects between a circuit on the circuit board and an external circuit,
The electric connection box for vehicles according to claim 1. The relay module has a cover disposed over the plurality of electrical coils and electrical contacts therein.
The vehicle electric junction box according to any one of claims 1 to 4.

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