JP2005233769A - Electric current sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify the structure of an electric current sensor, by covering magnetic circuit component parts and a magnetic sensor with an insulation sealing body. <P>SOLUTION: With the magnetic sensor 14 disposed in a gap 12g of a core 12, the core 12 and the magnetic sensor 14 are covered inside a sealed state, with the insulation sealing body 20 made of insulation resin. The sealing body 20 has a hole part 20h for detection allowing a conductor 30 to be disposed inside the core 12 of an annular shape, the conductor 30 serving as a measuring object. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a current sensor for detecting a measured current and related technology.

  Some current sensors have a core disposed around a path through which a current to be measured flows, and a Hall element disposed in a gap portion of the core. In such a current sensor, the current to be measured is detected by detecting magnetic energy generated by the current to be measured by a Hall element.

  In this type of current sensor, the core and the Hall element are integrated in a predetermined case body by positioning the core and the Hall element, and in this state, the potting resin is poured into the case body in a filling state. Some solidify.

  However, in the above-described integrated configuration example, a case body is separately formed in advance, the core and the hall element are positioned and disposed therein, and then potting resin is poured and solidified. Since the element is covered with a plurality of different materials, the configuration is complicated.

  Therefore, an object of the present invention is to simplify the configuration of the current sensor.

  A first aspect of the present invention is a current sensor including a magnetic circuit component, a magnetic sensor, and an insulating sealing body that covers the magnetic circuit component and the magnetic sensor so as to seal them.

  In this case, the magnetic circuit component is formed in a substantially annular shape, and the insulating sealing body has a shape having a detection hole in which a conductor through which a current to be measured flows can be disposed in the magnetic circuit component. It may be formed.

  The insulating sealing body may be integrated with a conductor through which a current to be measured flows.

  Further, peripheral circuit components of the magnetic sensor may be covered with the insulating sealing body together with the magnetic circuit component and the magnetic sensor.

  According to the first aspect of the present invention, since the magnetic circuit component and the magnetic sensor are covered with the insulating sealing body, the configuration is simplified.

  The magnetic circuit component is formed in a substantially annular shape, and the insulating sealing body is formed in a shape having a detection hole in which a conductor through which a current to be measured can flow can be disposed in the magnetic circuit component. In this case, by inserting a conductor through which the current to be measured flows into the detection hole, the current flowing through the conductor can be detected, which is excellent in versatility and is convenient.

  Furthermore, when the insulating sealing body and the conductor are integrated, the positional relationship between the conductor and the magnetic circuit components, the magnetic sensor, and the like can be accurately maintained, and the detection accuracy can be improved.

  Further, since the peripheral circuit components of the magnetic sensor are covered with the insulating sealing body together with the magnetic circuit components and the magnetic sensor, it is convenient to save the time for adding the peripheral circuit components later.

  Hereinafter, a current sensor according to an embodiment of the present invention will be described.

  FIG. 1 is a front view showing a current sensor, and FIG. 2 is a view showing an internal structure of the current sensor.

  The current sensor 10 includes a core 12, a magnetic sensor 14, a terminal 16, and an insulating sealing body 20 as magnetic circuit components.

  The core 12 is a magnetic body formed in a substantially annular shape (here, elongated and substantially annular), and a gap 12g is formed in a part of the circumferential direction (here, one end side in the longitudinal direction). Then, a conductor 30 such as a bus bar through which the current to be measured flows is arranged in the core 12 (see FIG. 2), and when a current is passed through the conductor 30 in this state, a magnetic field is generated around the conductor 30. The generated magnetic flux is converged on the core 12.

  As the magnetic sensor 14, a Hall element, an MR sensor, or the like is used. The magnetic sensor 14 is disposed in the gap 12g, detects the strength of the magnetic field in the gap 12g portion, and outputs a predetermined detection signal.

  Further, the terminal 16 is configured to be able to connect an external connection terminal. In the current sensor 10, three terminals 16 are used. Each terminal 16 is electrically connected to each input / output terminal of the magnetic sensor 14 via a wiring member 17 such as a wire wiring.

  The insulating sealing body 20 is formed of an insulating material such as an insulating resin, and a main body portion 20 a that covers the core 12 and the magnetic sensor 14 and a terminal holding portion 20 b that holds the terminals 16 are integrated. Formed.

  The main body 20a covers the core 12 and the magnetic sensor 14 in a state where the magnetic sensor 14 is disposed in the gap 12g of the core 12. The main body portion 20a has a substantially annular shape (here, a long and narrow annular shape) corresponding to the outer shape of the core 12, and a conductor 30 such as a bus bar to be measured can be disposed in a substantially central portion. A hole 20h is formed. Here, the detection hole 20h is formed in an elongated opening shape.

  The terminal holding part 20b is formed in a long shape (here, a substantially rectangular parallelepiped shape). The terminals 16 are held at appropriate intervals along the longitudinal direction of the terminal holding portion 20b. Each terminal 16 is held by the terminal holding portion 20b in such a manner that an external terminal can be connected. Energization to the magnetic sensor 14 and signal output from the magnetic sensor 14 are performed via these terminals 16.

  In such a current sensor 10, for example, a terminal in which each terminal 16 is connected to the magnetic sensor 14 via a wiring member 17 such as a wire wiring and the magnetic sensor 14 is disposed in the gap 12g of the core 12 is used. It is manufactured by pouring the insulating resin melted into the mold and insert molding it.

  The insulating resin used here is a resin used for a molded product, unlike a potting resin used for resin filling or the like, and generally has excellent deterioration resistance, heat resistance, wear resistance, and the like.

  The operation of the current sensor 10 configured as described above will be described.

  That is, a conductor 30 (for example, an elongated metal plate bus bar) through which a current to be measured flows is inserted and disposed in the detection hole 20 h of the insulating sealing body 20. When a current flows through the conductor 30 in this state, a magnetic field corresponding to the magnitude of the current is generated around the conductor 30. The resulting magnetic flux is converged on the core 12. Then, the magnetic sensor in the gap 12g portion is detected by the magnetic sensor 14, and a signal corresponding to the strength of the magnetic field, that is, the magnitude of the current flowing through the conductor 30, is output from the magnetic sensor 14 via the terminal 16. Become.

  According to the current sensor 10 configured as described above, since the core 12 and the magnetic sensor 14 are covered with the insulating sealing body 20, the case body and the potting resin poured into the case body as in the conventional case are used. In addition, the configuration can be simplified as compared with a configuration in which a plurality of different types of materials are covered.

  Further, since the detection hole 20h is formed in the insulating sealing body 20, the current flowing through the conductor 30 is detected by inserting the conductor 30 through which the current to be measured flows into the detection hole 20h. It is easy to use and has excellent versatility.

  FIG. 3 is a block diagram showing the electrical configuration of the power system in the hybrid vehicle. As shown in the figure, the electric power generated by the motor generator 42 in the hybrid vehicle is converted from alternating current to direct current by the inverter 43 and is supplied to the high voltage battery 45 via the relay box 44 at a predetermined high voltage. Separately, the power from the inverter 43 is stepped down by the DC-DC converter unit 46 and supplied to various electronic devices via the auxiliary battery 47 and the power distributor / relay box unit 48.

  In the hybrid vehicle shown in FIG. 3, the current sensor 10 is, for example, a portion indicated by a symbol “A”, that is, a power supply path to the high voltage battery 45 in the relay box 44 and a power supply to the auxiliary battery 47. And power supply path to various electronic devices in the power distributor / relay box unit 48. Then, by measuring the current in these power supply paths, for example, charge / discharge balance monitoring, charge control, load control, and the like regarding the high voltage battery 45 and the auxiliary battery 47 are performed.

  Of course, the application example of the current sensor 10 is not limited to the above example, and may be incorporated in a power supply path in a relay box of an automobile having a general internal combustion engine. It can also be used as a current sensor for motor (IWM) control and drive motor control of a fuel cell vehicle, an electric vehicle or the like.

  FIG. 4 is a perspective view showing a first modification of the current sensor.

  In the current sensor 10B, a conductor 30B through which a current to be measured flows is integrated into the detection hole 20h of the insulating sealing body 20 and is integrated. The conductor 30B is, for example, an elongated metal plate-like bus bar wiring body. For example, such a conductor 30B is insert-molded together with the core 12 and the magnetic sensor 14 when the insulating sealing body 20 is molded. Other configurations are the same as those of the current sensor 10.

  According to the current sensor 10B of the first modified example, since the insulating sealing body 20 and the conductor 30B are integrated, the positional relationship between the conductor 30B, the core 12, and the magnetic sensor 14 can be accurately maintained. , Detection accuracy can be improved. Further, it is convenient in that it is not necessary to insert the conductor 30B into the detection hole 20h later.

  FIG. 5 is a diagram illustrating a second modification of the current sensor.

  In this current sensor 10 </ b> C, a mounting circuit board 21 </ b> C that is a peripheral circuit component of the magnetic sensor 14 is covered with an insulating sealing body 20 </ b> C together with the core 12 and the magnetic sensor 14.

  More specifically, in the current sensor 10C, a portion corresponding to the terminal holding portion 20b is formed in the holding portion 20Cb having a slightly large extent.

  A mounting circuit board 21C in which the peripheral circuit of the magnetic sensor 14 is incorporated is incorporated in the holding portion 20Cb. Examples of the peripheral circuit of the magnetic sensor 14 include, for example, a power supply circuit that steps down the surrounding 12V voltage to 5V suitable for the magnetic sensor 14, a conversion circuit that converts the voltage output from the magnetic sensor 14 into a current output, and the like. Examples include a filter circuit including a capacitor. Further, each terminal 16 is connected to the magnetic sensor 14 from the mounting circuit board 21C through wire wiring or the like as appropriate.

  For example, the mounting circuit board 21 </ b> C is formed by injecting molten insulating resin into the mold together with the core 12 and the magnetic sensor 14, so that the insulating sealing body The 20C holding portion 20Cb is covered in a sealing manner.

  According to the current sensor 10 </ b> C configured in this way, the mounting circuit board 21 </ b> C is covered with the insulating sealing body 20 </ b> C together with the core 12 and the magnetic sensor 14. Convenient.

  In particular, by incorporating a transformer power supply circuit into the mounting circuit board 21C, the current sensor 10C can be installed without providing a separate power supply circuit around it, which is convenient. Further, by incorporating a conversion circuit that converts the voltage output into the current output in the mounting circuit board 21C, a current signal resistant to noise can be output.

It is a front view which shows the current sensor which concerns on embodiment of this invention. It is a figure which shows the internal structure of a current sensor same as the above. It is a block diagram which shows the electric constitution of the electric power system in a hybrid vehicle. It is a perspective view which shows the current sensor which concerns on a 1st modification. It is a figure which shows the internal structure of the current sensor which concerns on a 2nd modification.

Explanation of symbols

10, 10B, 10C Current sensor 12 Core 14 Magnetic sensor 20 Insulating sealing body 20h Detection hole 21C Mounting circuit board 30, 30B Conductor

Claims (4)

Magnetic circuit components,
A magnetic sensor;
An insulating sealing body covering the magnetic circuit component and the magnetic sensor so as to seal;
With current sensor. The current sensor according to claim 1,
The magnetic circuit component is formed in a substantially annular shape,
The said insulation sealing body is a current sensor currently formed in the shape which has the hole for a detection which can arrange | position the conductor through which a to-be-measured current flows in the said magnetic circuit component. The current sensor according to claim 1,
The insulation sealing body is a current sensor integrated with a conductor through which a current to be measured flows. The current sensor according to any one of claims 1 to 3,
A current sensor in which peripheral circuit components of the magnetic sensor are covered with the insulating sealing body together with the magnetic circuit components and the magnetic sensor.

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