Conversion adapter

Abstract

To resolve a state where a conversion adapter is overheated when an excess current for the conversion adapter flows with the conversion adapter located between a charging inlet and a charging plug.SOLUTION: A conversion adapter is interposed between a charging inlet, which receives power supply for charging a battery of a vehicle, and a charging plug connected to an external charging facility outside the vehicle, and enables power supply from the charging plug toward the charging inlet. The conversion adapter comprises an overheat protection unit that stops the charging when a temperature of a predetermined heat-generating part exceeds a predetermined threshold.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The technology disclosed in this specification relates to a conversion adapter for being interposed between a charging inlet and a charging plug.

Background Art

[0002] When the charging inlet that receives power supply for charging the battery of a vehicle and the charging plug that connects to an external charging facility have different specifications, a conversion plug is interposed between them to enable power supply from the charging plug to the charging inlet.

[0003] Patent Document 1 discloses an adapter in which the specifications of an input-side socket for accommodating a connector extending from a charging stand and an output-side connector for connecting to an electric vehicle are different.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Even when the conversion adapter is interposed between the charging inlet and the charging plug, the allowable current value for the current supplied from the charging facility to the vehicle is determined by communication between the charging facility and the vehicle. Therefore, when the allowable current value of the conversion adapter is smaller than the allowable current value determined as described above, it becomes an overcurrent for the conversion adapter, and there is a risk that the conversion adapter will be in an overheated state. This specification provides a technology for solving this problem.

Means for Solving the Problems

[0006] This specification discloses a conversion adapter that is interposed between a charging inlet that receives power supply for charging a battery of a vehicle and a charging plug that connects to an external charging facility, and enables power supply from the charging plug to the charging inlet. The conversion adapter includes an overheat protection unit that stops the charging when the temperature of a predetermined heat-generating part exceeds a predetermined threshold value.

[0007] According to the above configuration, the overheat protection unit of the conversion adapter stops the charging when the temperature of a predetermined heat-generating part exceeds a predetermined threshold value. Thereby, overheating of the conversion adapter due to overcurrent can be suppressed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0009] With reference to the drawings, this embodiment will be described. Each drawing is merely an example, and this embodiment is not limited to the illustrated content. Also, since each drawing is an example, the illustrated shape may not be accurate or a part may be omitted.

[0010] Figure 1 simply shows the charging system 1. The charging system 1 includes a vehicle 10, off-vehicle charging equipment 20, a charging plug 24, etc. The vehicle 10 is an electric vehicle. The electric vehicle is, for example, a battery electric vehicle or a plug-in hybrid electric vehicle, and includes a battery 12 that can be charged and discharged by an external power source, and a driving motor (not shown) that receives power supply from the battery 12. Further, the vehicle 10 includes a charging inlet 14 that receives power supply for charging the battery 12, and an ECU 16. ECU is the abbreviation of Electronic Control Unit. The ECU 16 is one of various ECUs mounted on the vehicle 10, and is, for example, an ECU for controlling the charging of the battery 12.

[0011] The charging equipment 20 is an AC power supply device. A charging cable 22 extends from the charging equipment 20, and the tip of the charging cable 22 is the charging plug 24. Usually, the user connects the charging equipment 20 and the vehicle 10 with the charging cable 22 by attaching the charging plug 24 to the charging inlet 14, and charges the battery 12. However, when the specifications such as the socket shape of the charging inlet 14 and the shape of the charging plug 24 are different, the charging plug 24 cannot be directly attached to the charging inlet 14. In order to eliminate such differences in specifications, the user uses a conversion adapter 30. Note that there are no particular restrictions on the specifications of the charging inlet 14 and the charging plug 24 respectively, and for example, known ones may be adopted.

[0012] The conversion adapter 30 has an input-side socket 32 corresponding to the specification of the charging plug 24 and an output-side plug 34 corresponding to the specification of the charging inlet 14. Therefore, the user attaches the charging plug 24 to the input-side socket 32 of the conversion adapter 30 and attaches the output-side plug 34 of the conversion adapter 30 to the charging inlet 14. As a result, the conversion adapter 30 is interposed between the charging plug 24 and the charging inlet 14, enabling power supply from the charging plug 24 to the charging inlet 14.

[0013] Figures 2, 3, and 4 each show a conversion adapter 30 interposed between the charging plug 24 and the charging inlet 14. The configuration shown in Figure 2 is called the first embodiment, the configuration shown in Figure 3 is called the second embodiment, and the configuration shown in Figure 4 is called the third embodiment. Any of the first, second, and third embodiments may be adopted. Inside the conversion adapter 30, the first power line 36, the second power line 38, the CPLT signal line 40, the connection signal line 42, and the ground signal line 44 are included as signal lines connecting the input-side socket 32 and the output-side plug 34. CPLT is an abbreviation for control pilot.

[0014] The positive first power line 36 connects the first positive terminal 24a of the power line of the charging plug 24 and the second positive terminal 14a of the power line of the charging inlet 14. Similarly, the negative second power line 38 connects the first negative terminal 24b of the power line of the charging plug 24 and the second negative terminal 14b of the charging inlet 14. The CPLT signal line 40 connects the first CPLT terminal 24c of the charging plug 24 and the second CPLT terminal 14c of the charging inlet 14. The CPLT signal is a control signal exchanged between the charging facility 20 and the ECU 16 of the vehicle 10. For example, from the charging facility 20 to the vehicle 10, the allowable current value is indicated by the CPLT signal. The CPLT signal line 40 mediates the transmission of such a CPLT signal. Since this allowable current value is a value determined in the relationship between the charging facility 20 and the vehicle 10, it may be too large for the conversion adapter 30.

[0015] The connection signal line 42 connects the first connection terminal 24d of the charging plug 24 and the second connection terminal 14d of the charging inlet 14, and mediates the transmission of a connection signal indicating the connection state between the charging plug 24 and the charging inlet 14. The ECU 16 can determine whether the charging inlet 14 and the charging plug 24 are connected according to the level of the connection signal input from the second connection terminal 14d. The ground signal line 44 connects the first ground terminal 24e of the charging plug 24 and the second ground terminal 14e of the charging inlet 14, and forms part of the ground wire.

[0016] The conversion adapter 30 includes a thermal protection unit 46 that stops the charging when the temperature of a predetermined heat - generating part exceeds a predetermined threshold value. As described above, the conversion adapter 30 has several signal lines connecting the terminals of the charging inlet 14 and the terminals of the charging plug 24. As shown in FIG. 2, according to the first embodiment, the thermal protection unit 46 has a thermostat 48 provided on the CPLT signal line 40. The thermostat 48 is a circuit that switches the switch off when the temperature of the detection target rises and switches the switch on when the temperature of the detection target falls.

[0017] The predetermined heat - generating part is a part in the conversion adapter 30 that is likely to increase in temperature due to overcurrent. Examples of the heat - generating part include a predetermined terminal where the input - side socket 32 contacts the charging plug 24, a predetermined terminal where the output - side plug 34 contacts the charging inlet 14, and other conductors such as bus bars for conducting current. As an example, as shown by the dashed line, the thermostat 48 acquires the temperature of the heat - generating part with the contact part between the second positive - electrode terminal 14a and the output - side plug 34 as the heat - generating part. For example, the thermostat 48 acquires the detected temperature of the heat - generating part detected by a temperature sensor (not shown). A configuration including such a temperature sensor and the thermostat 48 may be regarded as the thermal protection unit 46.

[0018] When the detected temperature exceeds a preset threshold value, the thermostat 48 cuts off the CPLT signal line 40. On the vehicle 10 side, when the ECU 16 detects the stop of the CPLT signal due to the cut - off of the CPLT signal line 40, the ECU 16 stops the charging of the battery 12 with the power supplied through the charging inlet 14.

[0019] As shown in FIG. 3, according to the second embodiment, the overheat protection unit 46 has a thermostat 48 provided on the connection signal line 42. The thermostat 48 cuts off the connection signal line 42 when the detected temperature exceeds the threshold value. On the vehicle 10 side, when the ECU 16 detects the cutoff of the connection signal line 42, it may stop charging the battery 12 with the power supplied via the charging inlet 14. From the perspective of the ECU 16, the cutoff of the connection signal line 42 is the same as the state where the connection of the charging plug 24 cannot be detected.

[0020] As shown in FIG. 4, according to the third embodiment, the overheat protection unit 46 has a thermostat 48 provided on the ground signal line 44. The thermostat 48 cuts off the ground signal line 44 when the detected temperature exceeds the threshold value. On the vehicle 10 side, when the ECU 16 detects the cutoff of the ground signal line 44, it may stop charging the battery 12 with the power supplied via the charging inlet 14.

[0021] It may also be configured such that the controller on the charging facility 20 side detects the cutoff of the signal line by the thermostat 48 as described above, and the charging facility 20 stops power supply to stop charging the battery 12. According to each of these embodiments, when the temperature of the heat - generating part exceeds the threshold value, the overheat protection unit 46 cuts off the signal line of the conversion adapter 30 to stop the charging for the vehicle 10 or the charging facility 20. That is, the cutoff of the signal line by the thermostat 48 results in an instruction to stop the charging for the vehicle 10 or the charging facility 20, and the vehicle 10 or the charging facility 20 stops the charging.

[0022] In any of the above - described embodiments, it is also possible to interpret by replacing the thermostat 48 with a thermistor 50. The thermistor 50 is a resistance element that changes its resistance value according to the temperature of the detection target. As shown in FIG. 5, the resistance value of the thermistor 50 rapidly increases when the temperature of the detection target exceeds the temperature TH which is the threshold value.

[0023] That is, in the first embodiment, the overheat protection unit 46 may have a thermistor 50 provided on the CPLT signal line 40. When the detected temperature exceeds the threshold value, the thermistor 50 increases the resistance value of the CPLT signal line 40. On the charging facility 20 side, for example, when the resistance value of the CPLT signal line 40 changes, there is a mechanism in which the voltage value of the CPLT signal line 40 to be monitored increases. When such an increase in the voltage value is recognized, the charging facility 20 stops power supply to stop the charging of the battery 12.

[0024] Similarly, in the second embodiment, the overheat protection unit 46 may have a thermistor 50 provided on the connection signal line 42. When the detected temperature exceeds the threshold value, the thermistor 50 increases the resistance value of the connection signal line 42. On the vehicle 10 side, when the ECU 16 detects an increase in the resistance value of the connection signal line 42, for example, it determines to decrease the allowable current value. Then, the ECU 16 stops the charging of the battery 12 with the power supplied through the charging inlet 14 according to such a determination.

[0025] Similarly, in the third embodiment, the overheat protection unit 46 may have a thermistor 50 provided on the ground signal line 44. When the detected temperature exceeds the threshold value, the thermistor 50 increases the resistance value of the ground signal line 44. On the vehicle 10 side, when the ECU 16 detects an increase in the resistance value of the ground signal line 44, it stops the charging of the battery 12 with the power supplied through the charging inlet 14.

[0026] According to each of these embodiments, when the temperature of the heat - generating part exceeds the threshold value, the overheat protection unit 46 increases the resistance value of the signal line of the conversion adapter 30, thereby causing the vehicle 10 or the charging facility 20 to stop the charging. That is, the increase in the resistance value of the signal line by the thermistor 50 results in an instruction to stop the charging for the vehicle 10 or the charging facility 20, and the vehicle 10 or the charging facility 20 stops the charging.

[0027] FIG. 6 shows, in a flowchart, the overheat protection of the present embodiment executed in the charging system 1 with the conversion adapter 30 interposed between the charging plug 24 and the charging inlet 14. After the start of charging of the battery 12, the overheat protection unit 46 of the conversion adapter 30 acquires the detected temperature of the heat generating part, and branches the process depending on whether or not the detected temperature exceeds a threshold value (step S100). When the detected temperature does not exceed the threshold value (No in step S100), charging is continued as it is (step S110), and the determination in step S100 is repeated.

[0028] When the detected temperature exceeds the threshold value (Yes in step S100), the overheat protection unit 46 cuts off a predetermined signal line that the conversion adapter 30 has or increases the resistance value, as described above (step S120). The vehicle 10 or the charging facility 20 regards this result as an instruction to stop charging, and stops charging the battery 12 (step S130).

[0029] As described above, according to the present embodiment, a conversion adapter 30 is disclosed that is interposed between a charging inlet 14 that receives power supply for charging a battery 12 included in a vehicle 10 and a charging plug 24 that is connected to an external charging facility 20, and enables power supply from the charging plug 24 toward the charging inlet 14. The conversion adapter 30 includes an overheat protection unit 46 that stops the charging when the temperature of a predetermined heat generating part exceeds a predetermined threshold value. According to this configuration, even if an excessive current temporarily flows through the conversion adapter 30 during charging of the battery 12, the charging can be stopped by the action of the overheat protection unit 46, and it is possible to suppress the conversion adapter 30 from entering an overheated state.

[0030] Further, according to the present embodiment, the conversion adapter 30 has a signal line connecting the terminals of the charging inlet 14 and the terminals of the charging plug 24. When the temperature of the heat generating portion exceeds the threshold value, the overheat protection unit 46 cuts off the signal line, thereby stopping the charging of the vehicle 10 or the charging facility 20. Specifically, the overheat protection unit 46 has a thermostat 48 provided on the signal line. According to such a configuration, it is possible to suppress the conversion adapter 30 from being in an overheated state with a simple configuration.

[0031] Further, according to the present embodiment, the conversion adapter 30 has a signal line connecting the terminals of the charging inlet 14 and the terminals of the charging plug 24. When the temperature of the heat generating portion exceeds the threshold value, the overheat protection unit 46 increases the resistance value of the signal line, thereby stopping the charging of the vehicle 10 or the charging facility 20. Specifically, the overheat protection unit 46 has a thermally variable resistor 50 provided on the signal line. According to such a configuration, it is possible to suppress the conversion adapter 30 from being in an overheated state with a simple configuration.

Explanation of Reference Numerals

[0032] 1: Charging system, 10: Vehicle, 12: Battery, 14: Charging inlet, 14a: Second positive terminal, 14b: Second negative terminal, 14c: Second CPLT terminal, 14d: Second connection terminal, 14e: Second ground terminal, 16: ECU, 20: Charging facility, 22: Charging cable, 24: Charging plug, 24a: First positive terminal, 24b: First negative terminal, 24c: First CPLT terminal, 24d: First connection terminal, 24e: First ground terminal, 30: Conversion adapter, 32: Input side socket, 34: Output side plug, 36: First power line, 38: Second power line, 40: CPLT signal line, 42: Connection signal line, 44: Ground signal line, 46: Overheat protection unit, 48: Thermostat, 50: Thermally variable resistor

Claims

1. A conversion adapter interposed between a charging inlet that receives power supply for charging a battery of a vehicle and a charging plug that connects to an external charging facility, enabling power supply from the charging plug to the charging inlet, The conversion adapter includes an overheat protection unit that stops the charging when the temperature of a predetermined heat generating part exceeds a predetermined threshold value.

2. The conversion adapter has a signal line connecting the terminals of the charging inlet and the terminals of the charging plug, The conversion adapter according to claim 1, wherein the overheat protection unit stops the charging to the vehicle or the charging facility by cutting off the signal line when the temperature of the heat generating part exceeds the threshold value.

3. The conversion adapter according to claim 2, wherein the overheat protection unit has a thermostat provided on the signal line.

4. The conversion adapter has a signal line connecting the terminals of the charging inlet and the terminals of the charging plug, The conversion adapter according to claim 1, wherein the overheat protection unit stops the charging to the vehicle or the charging facility by increasing the resistance value of the signal line when the temperature of the heat generating part exceeds the threshold value.

5. The conversion adapter according to claim 4, wherein the overheat protection unit has a thermally variable resistor provided on the signal line.

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