JP6585924B2 - Current value transmitter, current value receiver, and current value detection unit including these - Google Patents

Description

  The present invention relates to a current value transmitter, a current value receiver, and a current value detection unit including these.

  2. Description of the Related Art Conventionally, an in-vehicle battery checker that displays a current value and a voltage value measured using wireless communication at a position away from a measurement place is known. For example, Patent Document 1 discloses a measurement unit that measures a voltage value and a current value of a battery mounted on a car, a modulation unit that modulates a carrier wave signal using measurement data measured by the measurement unit, and a modulation unit that modulates the carrier signal. Transmitting means for wirelessly transmitting the carrier signal, receiving means for receiving the carrier signal transmitted by the transmitting means, and the voltage value and current value based on the measurement data obtained by demodulating by the demodulating means. There is described an in-vehicle battery checker that includes a display means for displaying to facilitate measurement of the voltage and current of a battery mounted on a car at the starter start time when a starter key is operated, for example.

JP-A-10-170615

  However, in such an in-vehicle battery checker, since a shunt resistor is used when measuring a current value, there is a problem that a measuring device is enlarged. Moreover, since heat is generated when the current value is measured, there is a problem that the current value may be affected by heat.

  This invention is made | formed in view of such a subject, and it aims at providing the small electric current value transmitter which can suppress generation | occurrence | production of a heat | fever and can alert | report an electric current value to the distant place. It is another object of the present invention to provide a current value receiver that receives a current value transmitted from the current value transmitter and a current value detection unit including these.

  The present invention adopts the following means in order to achieve at least one of the above-mentioned main objects.

The current value transmitter of the present invention is
A first terminal connected to the storage battery;
A second terminal connected to the electrical product;
A current measuring unit that measures a current value based on a change in a magnetic field caused by the flow of electricity between the first terminal and the second terminal;
A transmission unit that wirelessly transmits the current value measured by the current measurement unit by converting it into a digital signal;
A transmitter controller for controlling wireless transmission from the transmitter;
With
The current measurement unit, the transmission unit, and the transmitter control unit are sealed with resin .

  This current value transmitter is based on the change in the magnetic field caused by the flow of electricity flowing between the first terminal and the second terminal by connecting the first terminal to the storage battery and the second terminal to the electrical product. The current value is measured by the current measurement unit, converted into a digital signal by the transmission unit, and wirelessly transmitted. As described above, since the current value can be measured without using a shunt resistor or the like by measuring the current value based on the change in the magnetic field, it is possible to reduce the size of the measuring device for measuring the current value. it can. Further, by measuring the current value by this method, the heat generation of the current measuring unit can be reduced in advance.

At this time, the current value transmitter of the present invention is characterized in that the current measurement unit, the conversion unit, the transmission unit, and the transmitter control unit are sealed with resin . By suppressing the amount of heat generated at the time of measurement, it is not necessary to provide a heat dissipation function, so that it can be sealed with resin. By doing so, high waterproofness can be provided, and the possibility of malfunction or malfunction due to external water droplets or the like can be reduced in advance.

  Furthermore, in the current value transmitter of the present invention, the connection terminal and the current measurement unit may be electrically connected through a metal plate. By doing so, the amount of current flowing between the connecting portion and the current measuring portion can be increased, so that heat generation that occurs when a high current flows can be reduced in advance. The metal plate used at this time is preferably a plate having high electrical conductivity, such as a copper plate or an iron plate. By using a plate having high electrical conductivity, the generated heat can be reduced even when a high current flows.

  Furthermore, in the current value transmitter of the present invention, there may be a plurality of at least one of the positive terminal and the negative terminal. If it carries out like this, when connecting a some apparatus to a storage battery, the number of the connection lines connected to one connection terminal can be reduced. In other words, for example, when measuring the current value of a storage battery that is used by being connected to a plurality of electric appliances, such as a storage battery mounted on a camper, the number of connection lines connected to the terminals of the storage battery is reduced. Therefore, convenience can be improved.

  In the current value transmitter of the present invention, when the digital signal is wirelessly transmitted, the transmitter control unit wirelessly transmits the digital signal at an interval different from the immediately preceding digital signal transmission interval. The transmitter may be controlled as described above. In this way, even if multiple current value transmitters are used within the range where wireless transmission is possible, the transmission interval of the digital signal differs depending on the timing at which wireless transmission is first started. The possibility of doing this can be reduced in advance. In addition, even if radio waves interfere, the digital signal transmission interval varies depending on the timing at which radio transmission is first started, so the digital signal transmission timing changes to automatically eliminate radio wave interference. can do.

The current value receiver of the present invention is
A receiving unit that receives the digital signal transmitted from the current value transmitter according to any one of the above, and decodes the digital signal;
A display unit for displaying the current value decoded by the decoding unit;
A light detector for detecting ambient brightness;
A receiver control unit that changes the luminous intensity of the display unit based on the brightness detected by the light detection unit;
It is characterized by comprising.

  Since this current value receiver receives and displays the digital signal transmitted from any of the current value transmitters described above, the effect of any of the current value transmitters described above, for example, heat generation is reduced and the size is reduced. The effect that it can be done can be obtained. In addition, since the digital current value receiver includes a light detection unit that detects ambient brightness and displays the current value based on the brightness detected by the light detection unit, the current value is easy to visually recognize.

The current value detection unit of the present invention is
The current value transmitter;
The current value receiver;
It is characterized by comprising.

  Since this current value receiver includes any of the above-described current value transmitters and current value receivers, the effect of any of the above-described current value transmitters and current value receivers, for example, the small size of the device The effect of reducing the heat generation amount can be obtained.

FIG. 1 is a schematic diagram showing an outline of the configuration of the current value detection unit 10. FIG. 2 is a block diagram illustrating an example of electrical connection of the current value transmitter 20. FIG. 3 is a block diagram illustrating an example of electrical connection of the current value receiver 40. FIG. 4 is a flowchart illustrating an example of current value detection. FIG. 5 is a diagram illustrating an example of a standby time table stored in the ROM 52.

  Next, the current value detection unit 10 will be described in detail as an example of the embodiment of the present invention. The embodiments and drawings described below exemplify a part of the embodiments of the present invention, and are not used for the purpose of limiting to these configurations, and do not depart from the gist of the present invention. It can be changed as appropriate. In addition, the same or similar code | symbol is attached | subjected to the corresponding component in each figure.

  As shown in FIG. 1, a current value detection unit 10 that is an example of an embodiment of the present invention includes a current value transmitter 20 and a current value receiver that can receive a radio signal transmitted from the current value transmitter 20. 40. Thus, by enabling communication between the current value transmitter 20 and the current value receiver 40 by wireless communication, it is not necessary to connect the place where the current value is measured and the place where the current value is displayed to each other by wire. In other words, for example, there is no need to connect a place where a movable battery is loaded and a place where the current value is to be visually recognized, such as a battery loaded in a camper, so compared to the case where wired is used. Further, it is possible to reduce labor during installation. In addition, by making the current value receiver 40 portable, it is possible to move freely and check the current value anywhere where wireless communication is possible.

  As shown in FIGS. 1 and 2, the current value transmitter 20 includes a first terminal 22 a, a second terminal 22 b, a second terminal 22 c (hereinafter also referred to as “connection terminal 22”), and a current value detection unit 24. And a transmitter control unit 30 that controls the current value detection unit 24 and the wireless transmission unit 28. At this time, the first terminal 22a and the current value detector 24 are electrically connected by a metal plate 26a, and the second terminal 22 and the current value detector 24 are electrically connected by a metal plate 26b. . This current value transmitter 20 measures the value of the current flowing between the storage battery and the electrical product by connecting the first terminal 22a to the storage battery and the second terminal 22b or the second terminal 22c to the electrical product. Information including the value is wirelessly transmitted by the wireless transmission unit 28. By doing so, information including a current value can be transmitted to a place not connected by wire. The current value transmitter 20 is entirely coated with resin except for the connection terminals 22. By doing this, it is possible to reduce the possibility that water droplets or the like in the current value transmitter 20 will enter or that condensation will occur inside, and to reduce the possibility of failure or malfunction. .

  The connection terminal 22 is a combination of a known bolt and nut. Since the connection terminal composed of a combination of a bolt and a nut has a shape of a terminal that is adopted as a part of many battery wirings, it can be connected in the same procedure and has high convenience.

  The current value detection unit 24 is a current detection unit including an element that measures a current value based on a change in a magnetic field caused by a current. For example, a magnetic tunnel junction element (MJT element), a tunnel magnetoresistive element (TMR element), or the like. It is a current value detection part which measures a current value using the magnetoresistive element. As such a current detection unit, for example, HAL50 manufactured by LEM can be used. By using such a current value detection unit, it is possible to reduce power consumption when measuring a current value, compared to the case of measuring a current value by connecting an ammeter having a resistance in series with a circuit in series. Can do. The current value detector 24 is electrically connected to the first terminal 22a and the metal plate 26a, and the second terminal 22b and the second terminal 22c are electrically connected to each other via the metal plate 26b. The connection part of the metal plate 26a and the metal plate 26b, and the electric current value detection part 24 is electrically connected to the surface of the metal plate 26a and the metal plate 26b. By doing so, it is possible to reduce the amount of heat generated when electricity flows as compared to the case of connecting with thin wiring.

  The wireless transmission unit 28 is a known transmission antenna that converts the current value detected by the current value detection unit 24 into a digital signal and wirelessly transmits the signal using the 315 MHz band. When such a transmission antenna is used, for example, power consumption can be further reduced as compared with a case where various methods used in a wireless LAN or a Bluetooth (registered trademark) communication method is used. This is because when these methods are used, authentication between the transmitting side and the receiving side is performed, so that the communication capacity increases and more power is consumed. It should be noted that other types of transmission antennas may be used, and use of a Bluetooth (registered trademark) communication system or the like is not excluded. Even when such a communication method is used, one of the objects of the present invention to reduce the size of the apparatus can be obtained.

  As shown in FIG. 2, the transmitter control unit 30 is a microcomputer centered on a CPU 31, which is detected by a ROM 32 that stores various control programs including a current value measurement processing routine described later, and a current value detection unit 24. The RAM 33 temporarily stores current values and the like, and an interface 34 (hereinafter referred to as “I / F 34”) that controls communication with the current value detection unit 24, the wireless transmission unit 28, and the like. These are electrically connected by a bus 35. Note that an integrated circuit or a microchip that can perform the same processing may be used.

  As shown in FIGS. 1 and 3, the current value receiver 40 includes a wireless reception unit 42 that receives a signal transmitted by the wireless transmission unit 28, and a display unit 46 that displays a current value received by the wireless reception unit 42. A light detection unit 44 that detects ambient brightness, and a receiver control unit 50 that controls display on the display unit 46. When the current value receiver 40 receives the signal transmitted from the wireless transmission unit 28 by the wireless reception unit 42, the current value receiver 40 decodes the digital signal and displays the current value included in the digital signal on the display unit 46. By doing so, the current value detected by the current value detection unit 24 can be displayed on the display unit 46. At this time, since the current value transmitter 20 and the current value receiver 40 can transmit information by wireless communication, it is not necessary to connect the current value transmitter 20 and the current value receiver 40 by wire. For this reason, the current value receiver 40 can be moved to a desired location, and the value detected by the current value detection unit 24 can be displayed at the desired location.

  The wireless reception unit 42 is a known reception antenna that receives a wireless signal, and can receive and combine the digital signal transmitted by the wireless transmission unit 28.

  The light detection unit 44 is a known photosensor, detects the amount of ambient light with the light detection unit 44, and transmits information related to ambient brightness to the receiver control unit 50. The receiver control unit 50 adjusts the brightness of the display unit 46 based on the amount of light detected by the light detection unit 44.

  The display unit 46 displays a current value included in the digital signal received by the wireless reception unit 42. For example, a plurality of LEDs may be provided. By turning on only the LED that forms a desired number among the plurality of LEDs, the current value can be displayed based on the current value received by the wireless reception unit 42. At this time, the brightness of the current value displayed on the display unit 46 is adjusted based on the amount of light detected by the light detection unit 44. Specifically, when the amount of light detected by the light detection unit 44 is larger than a predetermined value, the light is displayed brightly, and when it is smaller than the predetermined value, the brightness is suppressed and displayed. By doing so, it is easy to visually recognize the current value even in a bright place such as outdoors, and it contributes to power saving by suppressing the brightness in a dark place.

  As shown in FIG. 3, the receiver control unit 50 is a microcomputer centered on the CPU 51, and is received by the ROM 52 that stores various control programs including a light display unit control processing routine described later, and the wireless reception unit 42. A RAM 53 that temporarily stores information relating to a current value included in a wireless signal, and an interface 54 (hereinafter referred to as “I / F 54”) that controls communication with the wireless reception unit 42, the display unit 46, the light detection unit 44, and the like. And is electrically connected by a bus 55. Note that an integrated circuit or a microchip that can perform the same processing may be used.

  Next, a detection method for detecting a current value using the current value detection unit 10 will be described in detail with reference to FIG. FIG. 4 is a flowchart showing an example of the current value measurement processing routine. This current value measurement processing routine is read from the ROM 52 by the CPU 31 and executed when power is supplied to the current value transmitter 20. When this current value measurement processing routine is executed, as shown in FIG. 4, the value i is set to zero as an initial setting, and the variable i is temporarily stored in the RAM 33 (step S110).

  Subsequently, the CPU 31 acquires the identification information (step S120), reads the standby time corresponding to the acquired identification information from the standby time table (see FIG. 5) stored in the ROM 32 (step S130), and reads the standby Wait for time (step S140). Specifically, the CPU 31 determines whether a changeover switch (not shown) provided in the current value transmitter 20 is ON or OFF, and when the changeover switch (not shown) is ON, the standby shown in FIG. With reference to the ON row of the time table, the standby time stored in the column corresponding to the value of the variable i is read from the ROM 52, and the system waits for this standby time. For example, when the changeover switch is ON and this routine is executed for the first time, the variable i is set to an initial value of zero, so the corresponding time of 1000 ms is read. Will wait for 1000ms.

  Next, the CPU 31 supplies power to the current value detection unit 24 and activates the current value detection unit 24 (step S150). As described above, supplying power to the current value detection unit 24 immediately before detecting the current value contributes to power saving more than when power is always supplied. When power is supplied to the current value detection unit 24, the current value detection unit 24 starts detecting the current value and outputs the detected current value (step S160).

  Subsequently, when the CPU 31 receives the current value output from the current value detection unit 24, the CPU 31 transmits the current value via the wireless transmission unit 28 (step S170). Specifically, when the current value is input to the wireless transmission unit 28, the current value is converted into a digital signal by an A / D converter (not shown) provided in the wireless transmission unit 28 and wirelessly transmitted. When the wirelessly transmitted current value is received by the wireless reception unit 42 provided in the current value receiver 40, the CPU 41 displays the current value on the display unit 46. By carrying out the current value receiver 40 by carrying out like this, a current value can be confirmed in a desired place.

  Now, after transmitting a current value in step S170, CPU31 stops supply of the electric power to the current value detection part 24 (step S180). As described above, by stopping the supply of power to the current value detection unit 24 after the detection of the current value is completed, it contributes to further power saving.

  Subsequently, the CPU 31 adds the value 1 to the variable i (step S190), determines whether or not the value of the variable i is larger than the value 4 (step S200), and the value of the variable i is larger than the value 4 Is determined, the value 5 is subtracted from the value of the variable i (step S210), and step S130 is executed again. By doing so, it is possible to periodically execute the five types of standby time by storing the five types of standby time in the standby time table.

  On the other hand, if it is determined in step S200 that the value of the variable i is 3 or less, step S130 is executed again. In such a case, because the standby time corresponding to the variable i exists in the standby time table, it is not necessary to execute step S220.

  Here, the case where the identification information is ON has been described as an example. However, even when the identification information is OFF, the same can be executed with only a different waiting time table row for reading the waiting time. .

  The current value detection unit 10 of the present embodiment described in detail above connects the electrodes of the storage battery to the connection terminals 22 respectively, detects the current value by the current value detection unit 24 based on the change of the magnetic field caused by the current, The wireless transmission unit 28 converts it into a digital signal and wirelessly transmits it. Thus, since the current value can be measured without using a shunt resistor or the like by measuring the current value based on the change in the magnetic field, the power consumption when measuring the current value can be suppressed. . Moreover, since the heat generation by the current measurement unit can be reduced by adopting this type of current measurement unit, the water resistance can be increased by sealing with resin.

  In addition, since the current value can be measured without high heat generation in this way, the entire current value transmitter 20 except the connection terminal 22 can be coated with resin. By doing this, it is possible to reduce the possibility that water droplets or the like in the current value transmitter 20 will enter or that condensation will occur inside, and to reduce the possibility of failure or malfunction. .

  Furthermore, since the connection terminal 22 and the current value detection unit 24 are connected to each other via the metal plate 26a or the metal plate 26b, generation of heat generated when a high current flows can be reduced in advance. In other words, it is particularly suitable for measuring the current value of a high-capacity storage battery such as a battery for automobiles or ships.

  Furthermore, since the connection terminal 22 has two second terminals, the number of connection lines connected to one connection terminal can be reduced when a plurality of devices are connected. In other words, for example, when measuring the current value of a storage battery that is used by being connected to a plurality of electric appliances, such as a storage battery mounted on a camper, the number of connection lines connected to the terminals of the storage battery is reduced. Therefore, convenience can be improved.

  And since the standby time for detecting the current value is not the same, even when multiple current value transmitters are used within the range where wireless transmission is possible, the digital signal is Since the transmission intervals are different, the possibility of radio wave interference can be reduced in advance. In addition, even if radio waves interfere, the digital signal transmission interval varies depending on the timing at which radio transmission is first started, so the digital signal transmission timing changes to automatically eliminate radio wave interference. can do.

  In addition, this invention is not limited to embodiment mentioned above at all, and as long as it belongs to the technical scope of this invention, it cannot be overemphasized that it can implement with a various aspect.

  For example, in the above-described embodiment, two second terminals are provided. However, three or more second terminals may be provided, or one second terminal may be provided. In any case, the same effect as the above-described embodiment can be obtained.

  In the embodiment described above, only the current value is detected. However, the voltage value may be detected together and wirelessly transmitted together with the current value. In this way, both the current value and the voltage value can be confirmed at a desired location.

  In the embodiment described above, the identification information is determined by turning on and off a switch (not shown). However, the identification information is not limited to two types, and three or more types of identification information are used by using three or more types of conversion switches. Alternatively, identification information may be stored in the ROM 32 in advance. In any case, the same effect as the above-described embodiment can be obtained.

  In the above-described embodiment, the radio signal transmitted from the current transmitter 20 is received by the current value receiver 40. However, instead of the current value receiver 40, it may be received by a portable information terminal or the like. Good. In this way, the current value can be confirmed without introducing a new current value receiver 40 by introducing a predetermined application into the portable terminal.

  As shown in the above-described embodiment, the present invention can be used as a measuring device that measures the current value of a battery, particularly in the electric field.

DESCRIPTION OF SYMBOLS 10 ... Current value detection unit, 20 ... Current value transmitter, 22 ... Connection terminal, 22a ... First terminal, 22b ... Second terminal, 22c ... Second terminal, 24 ... Current value detection part, 26a ... Metal plate, 26b DESCRIPTION OF SYMBOLS ... Metal plate, 28 ... Wireless transmission part, 30 ... Transmitter control part, 31 ... CPU, 32 ... ROM, 33 ... RAM, 34 ... Interface, 35 ... Bus, 40 ... Current value receiver, 42 ... Wireless reception part, 44 ... light detection unit, 46 ... display unit, 50 ... receiver control unit, 51 ... CPU, 52 ... ROM, 53 ... RAM, 54 ... interface, 55 ... bus.

Claims (6)

A first terminal connected to the storage battery;
A second terminal connected to the electrical product;
A current measuring unit that measures a current value based on a change in a magnetic field caused by the flow of electricity between the first terminal and the second terminal;
A transmission unit that wirelessly transmits the current value measured by the current measurement unit by converting it into a digital signal;
A transmitter controller for controlling wireless transmission from the transmitter;
With
The current measurement unit, the transmission unit, and the transmitter control unit are sealed with resin,
Current value transmitter. The first terminal, the second terminal, and the current measuring unit are electrically connected via a metal plate,
The current value transmitter according to claim 1 . The second terminal is a plurality,
The current value transmitter according to claim 1 or 2 . The transmitter control unit controls the transmission unit so that when the digital signal is wirelessly transmitted, the transmission interval of the digital signal is wirelessly transmitted at an interval different from the transmission interval of the immediately preceding digital signal. And
The current value transmitter according to any one of claims 1 to 3 . A receiving unit that receives the digital signal transmitted from the current value transmitter according to any one of claims 1 to 4 and decodes the digital signal into a current value;
A display unit for displaying the current value received by the receiving unit;
A light detector for detecting ambient brightness;
A receiver control unit that changes the luminous intensity of the display unit based on the brightness detected by the light detection unit;
Characterized by comprising
Current value receiver. The current value transmitter according to any one of claims 1 to 4 ,
The current value receiver according to claim 5 ,
Characterized by comprising
Current value detection unit.

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