Power supply drive circuit

Abstract

To provide a technology for simultaneously driving devices with different drive voltages using a general-purpose relay.SOLUTION: A power supply drive circuit according to an embodiment includes a first power supply connected to a first device via a first relay, a second power supply having a higher voltage than the first power supply and connected to a second device via a second relay, and an ECU that controls the first relay and the second relay to drive both the first device and the second device simultaneously.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to a power supply driving circuit. [Background technology]

[0002] In a vehicle, equipment such as mounted objects and auxiliary machinery is supplied with power from a power source such as a battery under the control of an ECU (Electronic Control Unit) (see, for example, Patent Document 1).

[0003] Additionally, vehicles contain equipment that runs on 12 V and equipment that runs on 24 V. For example, when using a 12 V ECU to control equipment that runs on 24 V, it is necessary to use a relay with 24 V contacts and 12 V coils, or to use a step-up device to boost the voltage from 12 V to 24 V. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-156269 Summary of the Invention [Problem to be solved by the invention]

[0005] However, relays with a 24V contact side and a 12V coil side have the problem of being larger and more expensive than general-purpose relays. Furthermore, when using a booster device, there is a problem that even if the voltage is boosted, it may not be usable with devices that operate at 24V, depending on the current value set by the booster device.

[0006] The present invention has been made in view of the above circumstances, and its object is to provide a circuit that can simultaneously drive devices with different drive voltages using a general-purpose relay. [Means for solving the problem]

[0007] The power supply driving circuit according to the embodiment includes a first power supply connected to a first device via a first relay, a second power supply having a higher voltage than the first power supply connected to a second device via a second relay, and an ECU that controls the first relay and the second relay to drive both the first device and the second device simultaneously. [Effects of the Invention]

[0008] According to the power supply driving circuit described above, devices with different driving voltages can be driven simultaneously using a general-purpose relay. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the configuration of a power supply driving circuit according to the prior art. [Figure 2] FIG. 2 is a diagram showing the configuration of a power supply driving circuit according to the prior art. [Figure 3] FIG. 3 is a diagram illustrating an example of a power supply driving circuit according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] The power supply circuit will be described in detail below with reference to the drawings. In the following embodiments, parts with the same numbers perform the same operation, and redundant description will be omitted. For example, when there are multiple identical or similar elements, a common reference number may be used to describe each element without distinguishing between them, or a subnumber may be used in addition to the common reference number to describe each element with distinction between them.

[0011] [Embodiment] First, the prior art will be described. Vehicle equipment is mainly powered by 12V and is therefore supplied with power from a 12V power supply. However, some mounted equipment, including backup lamps, meter lights, etc., is powered by 24V. Therefore, when both such equipment powered by 12V (hereinafter referred to as 12V equipment) and equipment powered by 24V (hereinafter referred to as 24V equipment) are operated under the control of a 12V ECU, conventionally, a relay with 24V contacts and 12V coils, or a step-up device, is used to drive the 24V equipment.

[0012] 1 and 2 are diagrams showing the configuration of a power supply driving circuit according to the prior art. The power supply drive circuit in Figure 1 shows an example of a circuit using a 24V contact side / 12V coil side relay, while Figure 2 shows an example of a circuit using a boost device. Also, in the examples in Figures 1 and 2, the wiring that supplies 24V voltage is shown thicker than the wiring that supplies 12V voltage.

[0013] The power supply drive circuit of FIG. 1 includes a 12V ECU 10, a 12V relay 20, a 24V contact side / 12V coil side relay (hereinafter simply referred to as an external relay 30, the same as in FIG. 1) 30, and a 24V device 40.

[0014] The 12V ECU 10 is connected to a 12V relay 20. The 12V ECU 10 operates to ground the wiring connected to the 12V relay 20 in response to an input signal that is an instruction to drive a 24V device.

[0015] The 12V relay 20 includes a switch 201 and a coil unit 202. The 12V relay 20 may be a so-called general-purpose relay. One end of the switch 201 is connected to a 12V+B power supply, and the other end is connected to the external relay 30. Here, the 12V+B power supply refers to a 12V battery power supply. Although not shown in FIG. 1, the switch 201 may of course be connected not only to the external relay 30 but also to 12V devices.

[0016] One end of the coil 202 of the 12V relay 20 is connected to the 12V+B power supply, and the other end is connected to the 12V ECU 10. When a current flows through the coil 202, the switch 201 becomes conductive, and power from the 12V+B power supply is supplied to the external relay 30.

[0017] The external relay 30 includes a switch 301 and a coil 302. The external relay 30 is a special relay with a 24V contact side and a 12V coil side. One end of the switch 301 is connected to a 24V+B power supply, and the other end is connected to a 24V device 40. Here, the 24V+B power supply is a battery power supply having a voltage of 24V. The 24V+B power supply may be, for example, a power supply in which 12V batteries are connected in series.

[0018] One end of the coil 302 is connected to the switch 201 of the 12V relay 20, and the other end is grounded. When a current flows through the coil 302, the switch 301 becomes conductive, and power from the 24V+B power supply is supplied to the 24V device 40.

[0019] The 24V device 40 is a device that is driven by 24V, and may be, for example, mounted devices including a backup lamp, meter illumination, and the like.

[0020] For example, when an input signal is input to the 12V ECU 10, the 12V ECU 10 grounds the wiring connected to the 12V relay 20. As a result, power is supplied from the 12V+B power supply to the coil section 202, the switch 201 is turned on, and power from the 12V+B power supply is supplied to the coil 302 of the external relay 30. When power is supplied to the coil 302, the switch 301 is turned on, and power is supplied from the 24V+B power supply to the 24V device 40. In this way, the circuit in FIG. 1 is a circuit that allows the 12V ECU 10 to control the drive (operation) of the 24V device 40 by using the external relay 30.

[0021] The power supply drive circuit of FIG. 2 includes a 12V ECU 11, a 12V relay 21, a voltage step-up device 51, and a 24V device 41.

[0022] The 12V ECU 11 is connected to the 12V relay 21 in the same manner as in Fig. 1. When an input signal is received, the 12V ECU 11 operates to ground the wiring connected to the 12V relay 21.

[0023] The 12V relay 21 includes a switch 211 and a coil unit 212. One end of the switch 211 is connected to the 12V+B power supply, and the other end is connected to the boost device 51. When a current flows through the coil unit 212, the switch 211 becomes conductive, and power from the 12V+B power supply is supplied to the boost device 51.

[0024] The step-up device 51 is, for example, a booster that can boost a voltage value of 12V to a voltage value of 24V. For example, when the switch 211 is turned on, the voltage (12V) supplied from the 12V+B power supply is boosted to 24V. Then, the power boosted to 24V is supplied to the 24V device 41. In this way, the circuit in FIG. 2 is a circuit that allows the 12V ECU 11 to control the driving of the 24V device 41 by using the step-up device 51.

[0025] 1 is a special relay, as described above, and has the problem of being expensive. Furthermore, the external relay 30 is larger than other general-purpose relays (for example, the 12V relay 20), which means that there are significant design constraints. Furthermore, the external relay 30 needs to operate the switch 301 with the 12V power applied to the coil 302, which means that the setting is more complicated than that of a general-purpose relay.

[0026] 2 has a limited number of ports. If there are no available ports for 24V devices, a new boost device 51 must be installed, which increases costs and imposes significant design constraints. Furthermore, a current value for the boost device 51 must be set to boost the voltage to an appropriate value, but this current value may not be suitable for driving the 24V device 41.

[0027] Therefore, in this embodiment, a power supply driving circuit is provided that does not use an external relay 30 and a voltage step-up device 51 and that can simultaneously drive a 12V device and a 24V device.

[0028] FIG. 3 is a diagram illustrating an example of a power supply driving circuit according to an embodiment. The power supply drive circuit is a circuit mounted on vehicles such as electric vehicles, hybrid vehicles, hydrogen vehicles, etc. However, the vehicle on which the power supply drive circuit is mounted is not limited to the above-mentioned vehicles, and may be any vehicle that requires the simultaneous driving of 12V and 24V devices using a 12V power supply and a 24V power supply.

[0029] For example, the power supply drive circuit in Fig. 3 includes a 12V ECU 12, a 12V relay 22, a 24V relay 32, a 12V device 52, a 24V device 42, a first diode 62, and a second diode 72. In the example of Fig. 3, the wiring to which the 24V voltage is supplied is depicted as being thicker than the wiring to which the 12V voltage is supplied.

[0030] The 12V ECU 12 is connected to both the 12V relay 22 and the 24V relay 32. A first diode 62 is installed between the 12V ECU 12 and the 12V relay 22, and a second diode 72 is installed between the 12V ECU 12 and the 24V relay 32. When the 12V ECU 12 receives an input signal indicating that both the 12V device 52 and the 24V device 42 are to be driven, the 12V ECU 12 grounds the wiring connected to the 12V relay 22 and the 24V relay.

[0031] The 12V relay 22 includes a switch 221 and a coil unit 222. One end of the switch 221 is connected to the 12V+B power supply, and the other end is connected to the 12V device 52. One end of the coil unit 222 is connected to the 12V+B power supply, and the other end is connected to the 12V ECU 12. When a current flows through the coil unit 222, the switch 221 becomes conductive, and power from the 12V+B power supply is supplied to the 12V device 52.

[0032] The 24V relay 32 includes a switch 321 and a coil unit 322. One end of the switch 321 is connected to the 24V+B power supply, and the other end is connected to the 24V device 42. One end of the coil unit 322 is connected to the 24V+B power supply, and the other end is connected to the 12V ECU 12. When a current flows through the coil unit 322, the switch 321 becomes conductive, and power from the 24V+B power supply is supplied to the 24V device 42.

[0033] Furthermore, the 12V relay 22 and the 24V relay 32 may be general-purpose relays, but of course other relays may also be used. For example, when the 12V ECU 12 is grounded, the power supplied from the 12V+B power supply and the 24V+B power supply to the coil 222 of the 12V relay 22 and the coil 322 of the 24V relay can be identified. An appropriate relay may be used depending on the power supplied.

[0034] The 12V device 52 is a device installed in the vehicle that is powered by 12 V. The 12V device 52 may be any device that can be powered by 12 V, and therefore a detailed description thereof will be omitted here.

[0035] The 24V device 42 is a device that is placed inside or outside the vehicle and is powered by 24 V. For example, the 24V device 42 may be any device that can be powered by 24 V, and therefore a detailed description thereof will be omitted here.

[0036] The first diode 62 is a diode that is set so that the 24V+B power supply does not flow from the coil portion 322 of the 24V relay 32 to the coil portion 222 of the 12V relay 22 .

[0037] The second diode 72 is a diode that is set so that the 12V+B power supply does not flow from the coil portion 222 of the 12V relay 22 to the coil portion 322 of the 24V relay 32 .

[0038] The first diode 62 and the second diode 72 are connected at a connection point S in the wiring on the 12V ECU side. That is, the first diode 62 and the second diode 72 are connected at the connection point S between the 12V ECU 12.

[0039] Furthermore, the first diode 62 and the second diode 72 may be any diode that does not allow unintended power to flow into the 12V relay 22 and the 24V relay 32, respectively.

[0040] For example, when an input signal is input to the 12V ECU 12, the 12V ECU 12 operates to ground the wiring connected to the 12V relay 22 and the 24V relay 32. As a result, power is supplied from the 12V+B power supply to the coil section 222 and from the 24V+B power supply to the coil section 322. Then, the switches 221 and 321 become conductive, and power is supplied from the 12V+B power supply to the 12V device 52 and from the 24V+B power supply to the 24V device 42. As a result, the 12V device 52 and the 24V device 42 are driven simultaneously.

[0041] Note that power from the 24V+B power supply is not supplied to coil portion 222 of 12V relay 22 by first diode 62. Similarly, power from the 12V+B power supply is not supplied to coil portion 322 of 24V relay 32 by second diode 72. This prevents unintended power from being supplied to coil portion 222 and coil portion 322, preventing relay failure.

[0042] (Effects of the embodiment) The drive circuit of the embodiment described above can simultaneously drive the 12V device 52 and the 24V device 42 using a general-purpose relay without using the external relay 30 or the boost device 51. This reduces the cost of manufacturing a vehicle. Furthermore, the 12V relay 22 and the 24V relay use general-purpose relays. This reduces design constraints on the vehicle.

[0043] [Other embodiments] In short, this invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in combination as appropriate as possible, and in such cases, the combined effects can be obtained. Furthermore, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the disclosed multiple constituent elements. [Explanation of symbols]

[0044] 10, 11, 12…12V ECU 20, 21, 22...12V relay 30...External relay 32...24V relay 40,41,42…24V equipment 51...Boost equipment 52…12V equipment 62...Diode 72...Diode 201, 211, 212, 321... Switches 202, 212, 213, 322...Coil section 301...Switch 302...Coil

Claims

1. a first power source connected to the first device via a first relay; a second power supply having a higher voltage than the first power supply and connected to a second device via a second relay; an ECU that controls the first relay and the second relay to simultaneously drive both the first device and the second device; A power supply driving circuit comprising:

2. a first diode disposed between the first relay and the ECU; a second diode disposed between the second relay and the ECU; 10. The power supply driver circuit of claim 1 further comprising:

3. the first diode and the second diode have connection points to wiring between the first diode and the ECU; 3. The power supply driving circuit of claim 2.

4. When an input signal is input, the ECU operates to ground a first coil portion included in the first relay and a second coil portion included in the second relay so that power is supplied from the first power supply and the second power supply to the first coil portion and the second coil portion, respectively.

2. The power supply driving circuit of claim 1.

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