JP3890714B2 - Non-contact power feeding device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-contact power supply apparatus that supplies electric power to an electric moving body in a non-contact manner.
[0002]
[Prior art]
FIG. 5 is a block diagram showing a configuration of a conventional non-contact power feeding apparatus. In this apparatus, when a high-frequency current is passed through the primary power supply line 1, a voltage is induced in the pickup coil 2 magnetically coupled to the primary power supply line 1 due to the generated magnetic field, and the non-current from the primary power supply line 1 to the pickup coil 2. It is configured to transmit power by contact. The pickup coil 2 and the capacitor 3 constitute a resonance circuit, reducing reactive power and increasing power transmission efficiency. The output of the pickup coil 2 is rectified by the rectifier circuit 4, stabilized by the constant voltage circuit 5, and supplied to the inverter 6. The inverter 6 converts the output of the constant voltage circuit 5 into alternating current and outputs it to the linear motor 7.
[0003]
[Problems to be solved by the invention]
By the way, when the load is released for some reason in the non-contact power feeding device, an overcurrent is generated in the pickup coil 2 and an excessive voltage is applied to the resonance capacitor 3. Alternatively, if an abnormality such as a short circuit occurs in the linear motor 7, the output voltage of the inverter 6 is lowered. In the inverter 6, if the voltage is lowered to supply a constant power, the current increases, and as a result An excessive current flows through the rectifying unit 4, the constant voltage circuit 5, and the inverter 6. When the circuit is released in this state, an excessive current is also generated in the pickup coil 2.
As described above, when an overcurrent flows in an overload state or an abnormality such as an element failure occurs, each power supply circuit component generates heat. If the heat is left unattended, there is a risk that these parts will be overheated and broken or burnt. In addition, it is necessary to stop the power supply from the non-contact power supply device even when other devices or devices fail.
[0004]
To solve this problem, the secondary side circuit of the pickup coil 2 is a resonance circuit. Therefore, if this secondary side circuit is short-circuited, it is released from the resonance state, as if it is a CT (current transformer). Therefore, overheating due to overcurrent flowing through the pickup coil 2 can be prevented. Moreover, since the input voltage of the constant voltage circuit 5 is almost 0 V, heat generation of the control element of the constant voltage circuit 5 can be prevented. That is, when any abnormality occurs in the non-contact power feeding device, the heat generation of the pickup coil 2 or the control element is detected and the secondary side may be short-circuited. Alternatively, the input from the pickup coil 2 may be blocked before the resonance capacitor 3.
[0005]
However, the non-contact power feeding device is used as a power source, and all circuit portions are operated with the power from the pickup coil 2. Therefore, when the pickup coil 2 is short-circuited, the voltage of the constant voltage circuit 5 becomes almost 0V, so that the power supply of the control system becomes 0V and the control circuit does not function. Therefore, if the pickup coil 2 is short-circuited by an electrical means such as a relay or a switching element (FET, transistor), the power source of the control circuit disappears. Therefore, the relay and the switching element are released from the short-circuit state again, and the power is turned on. It becomes impossible to escape from the overheated condition. Further, since power is supplied again to other failed devices and devices, there is a possibility that a secondary failure may occur.
Further, when a self-holding element such as a thyristor is used, an electric signal for returning cannot be sent, so that it cannot be returned again. In order to recover, it is necessary to take out the motor unit equipped with the non-contact power feeding device and give an electric signal from the outside. For this reason, there is a problem in that until the carriage returns to the other normal carriages, if there is only one carriage path, the carriage cannot proceed and all conveyance stops.
[0006]
The present invention has been made in consideration of such points, and senses the heat of the pickup coil and elements, shorts the secondary side of the pickup coil by means other than electrical signals, or shuts off the secondary side input unit. This is a device that automatically returns to its original state when the temperature drops, and provides a contactless power supply device that eliminates problems associated with loss of control power and prevents overheating of the pickup coil and elements. Objective.
[0007]
[Means for Solving the Problems]
The present invention includes a primary side electric wire to which a high frequency current is supplied, a secondary side pickup coil that extracts power by electromagnetic coupling in a resonance state with the primary side electric wire, and a resonance capacitor, and outputs the secondary side pickup coil In a non-contact power feeding device that outputs a direct current power supply via a stabilized power supply circuit, the temperature of the pickup coil or power supply circuit component is constant between both ends of the pickup coil in parallel with the resonance capacitor. A non-contact power feeding characterized in that a thermostat is inserted in which the both ends of the pickup coil are short-circuited so that the pickup coil is brought out of the resonance state when it becomes above and the current continues to flow during the ON period. Device .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a non-contact power feeding device according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view showing a configuration of a linear motor type transport device equipped with the non-contact power feeding device.
First, in FIG. 2, reference numeral 21 denotes a ceiling frame, and support frames 22, 22 extending vertically downward are attached to the ceiling frame 21, and a long plate-shaped track plate 23 is attached to the lower ends of these support frames 22, 22. Is attached. A guide frame 24 is attached to the upper surface of the track plate 23. The guide frame 24 supports a linear motor type conveying device disposed therein in a movable manner. The guide frame 24 has a bottom plate portion 24a having a long plate-like permanent magnet 26 attached to a central portion thereof, and both ends of the bottom plate portion 24a. Vertical leg portions 24b, 24b connected to each other, and substantially U-shaped guide portions 24c, 24c connected to the vertical leg portions 24b, 24b.
[0009]
Further, in the linear motor type conveying device provided in the guide frame 24, reference numeral 27 denotes a horizontal frame, and a linear motor coil 28 is attached to the center of the horizontal surface of the lower surface of the horizontal frame 27 so as to face the permanent magnet 26. The free wheels 29 and 29 are attached to the lower surface of the horizontal frame 27 with the linear motor coil 28 interposed therebetween. Further, a block 30 in which a non-contact power supply and the like are housed is attached to the center of the upper surface of the horizontal frame 27, and branch mechanisms 31, 31 are attached to the side surfaces of the block 30. Guide rollers 32 and 32 are attached to the tip of 31. Guide rollers 33 are also attached to both sides of the upper surface of the horizontal frame 27.
[0010]
E-shaped magnetic cores 34 and 34 are attached to the upper surfaces of the branch mechanisms 31 and 31 described above. FIG. 3 is an enlarged view of the magnetic core 34, and the primary power supply lines 1 and 1 are arranged above and below the magnetic core 34. The primary power supply lines 1 and 1 are attached to one end portions of the support members 35 and 35, and the other end portions of the support members 35 and 35 are attached to the guide portion 24 c of the guide frame 24. An attachment member 38 is attached to the upper portion of the block 30, and a storage box 39 in which a member to be conveyed is stored is attached to the attachment member 38.
[0011]
Next, in FIG. 1, 1 is a primary power supply line (see FIGS. 2 and 3), 2 is a pickup coil (FIG. 3), 3 is a resonance capacitor, 4 is a rectifier circuit, 5 is a constant voltage circuit, and 6 is an inverter. , 7 is a linear motor composed of the coil 28 and the permanent magnet 26 shown in FIG. 2, and these structures are the same as those shown in FIG.
In this figure, the difference from FIG. 5 is a thermostat 11, which is arranged in the immediate vicinity of the pickup coil 2, and its NO (normally open) contact is connected in parallel to the resonance capacitor 3.
[0012]
Next, the operation of the above-described contactless power supply device will be described. First, when each part of the apparatus is operating normally, the operation is exactly the same as that of the apparatus shown in FIG. Next, when an abnormality occurs in any of the rectifier circuit 4, the constant voltage circuit 5, the inverter 6, and the linear motor 7, and an overcurrent flows through the pickup coil 2, the temperature of the coil 2 rises. When the temperature of the pickup coil 2 rises and reaches a certain temperature, the NO contact of the thermostat 11 is turned on, whereby both ends of the pickup coil 2 are short-circuited, and power supply to the circuits after the rectifier circuit 4 is stopped. The Here, repair of the abnormal part is performed by the staff. Next, when time elapses and the temperature of the pickup coil 2 decreases, the NO contact of the thermostat 11 is turned off, and the power supply is automatically restored.
[0013]
As described above, according to the above embodiment, since the thermostat 11 is used, both ends of the pickup coil 2 can be short-circuited without a power source in the event of an abnormality, and can be automatically restored due to a temperature drop.
In addition, according to the said embodiment, although the contact of the thermostat 11 is inserted between the both ends of the pick-up coil 2, it may replace with this and may be inserted between the output terminals of the rectifier circuit 4 (dashed line of FIG. 1). reference).
[0014]
FIG. 4 is a diagram illustrating a configuration of a contactless power feeding device according to another embodiment of the present invention. According to this embodiment, the NC (normal close) contact of the thermostat 11 is inserted in series with the pickup coil 2. As a result, when the temperature of the pickup coil 2 rises and reaches a certain temperature, the NC contact of the thermostat 11 is turned off, whereby the circuit of the pickup coil 2 is cut off, and power is supplied to the circuits after the rectifier circuit 4. Stopped. And when temperature falls, it will reset automatically.
1 and 4 described above, the thermostat 11 is arranged very close to the pickup coil 2 to detect an abnormal circuit operation based on the temperature rise of the pickup coil 2. Instead of this, abnormality detection may be performed based on the temperature of elements that generate heat when abnormality occurs, such as a rectifying element (diode or the like) in the rectifier circuit 4 and a control element (transistor or the like) in the constant voltage circuit 5.
[0015]
【The invention's effect】
As described above, according to the present invention, since the thermostat is used for temperature detection and circuit short-circuiting, the circuit can be short-circuited without an electric signal, and if the temperature is further lowered, automatic recovery can be achieved. can get.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a non-contact power feeding device according to an embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view showing a configuration of a linear motor type conveyance device equipped with the non-contact power feeding device of FIG.
FIG. 3 is an enlarged view of the magnetic core 34 of FIG.
FIG. 4 is a diagram illustrating a configuration of a contactless power feeding device according to another embodiment of the present invention.
FIG. 5 is a block diagram showing a configuration of a non-contact power feeding device mounted on a conventional linear motor type transport vehicle.
[Explanation of symbols]
1. Primary feeder line2. 2. Pickup coil 3. Resonance capacitor 4. Rectifier circuit 5. Constant voltage circuit Inverter 7. Linear motor 11. thermostat

Claims (1)

A primary side electric wire to which a high frequency current is supplied; a secondary side pickup coil that extracts power by electromagnetic coupling in a resonance state with the primary side electric wire; and a resonance capacitor, and rectifies the secondary side pickup coil output; In a non-contact power feeding device that outputs as a DC power source via a stabilized power circuit,
In parallel with the resonance capacitor, the pickup is turned on when the temperature of the pickup coil or power supply circuit component exceeds a certain value between both ends of the pickup coil so that the pickup coil is released from the resonance state. A non-contact power feeding apparatus comprising a thermostat in which a current is kept flowing during an ON period by short-circuiting both ends of a coil.

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