JPH0974034A - Noncontact transmitting device for power and signal and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability by eliminating noise due to the leakage magnetic flux of a coil for transmitting power. SOLUTION: A transmission device houses a core 2 for transmitting power for housing a coil 3 for transmitting power and a core 4 for transmitting signal for housing a coil 5 for transmitting signal in a frame 1 made of a non-magnetic body by magnetically separating them in a non-contact signal transmission device where the coil 5 for transmitting signal and a coil 3 for transmitting power are concentrically arranged in a transformer core. A transformer primary side 10 is constituted and a transformer secondary side 20 in the same configuration is allowed to oppose the transformer primary side 10 via a space 7. Also, a coil 6 for canceling noise which is inversely wound as compared with the coil 5 for transmitting signal is provided in the periphery of the outside of the core 4 for transmitting signal and the coil 5 for transmitting signal and the coil 6 for canceling noise are connected in series, thus canceling noise due to the leakage magnetic flux of the coil 3 for transmitting power.

Description

Detailed Description of the Invention

[0101]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contactless power and signal transmission device for contactlessly transmitting power and electric signals and a method for manufacturing the same.

[0092]

2. Description of the Related Art As a conventional technique, there is a rotary transformer in which a signal transmission coil and a power transmission coil are concentrically mounted in a pair of flat cylindrical transformer cores which are opposed to each other with a gap therebetween (for example, a practical transformer). 58-180616).

[0093]

However, in the prior art, since the signal transmission core and the power transmission core are shared, the leakage flux of the power transmission coil is interlinked with the signal transmission coil and noise is generated. Therefore, there is a problem that an erroneous signal is transmitted. Therefore, an object of the present invention is to provide a highly reliable contactless power and signal transmission device and a method for manufacturing the same, which eliminates noise due to a leakage magnetic flux of a power transmission coil.

[0093]

In order to solve the above problems, a power transmission core 2 in which a power transmission coil 3 is housed in a ring-shaped groove and a signal transmission coil 5 in a ring-shaped groove are provided. A contactless power and signal transmission device in which a pair of flat cylindrical transformer cores concentrically arranged with a housed signal transmission core 4 are opposed to each other through a gap, wherein the power transmission core 2 and the signal transmission core are provided. The core 4 is magnetically separated and housed in a non-magnetic frame. The transformer primary side 10 is configured as described above, and the transformer secondary sides 20 having the same configuration are opposed to each other through the gap G. Further, a noise canceling coil 6 having a reverse winding to that of the signal transmitting coil 5 that interlinks with the magnetic flux generated by the power transmitting coil 3 is provided outside the periphery of the signal transmitting core 4, The noise coil 5 and the noise canceling coil 6 are connected in series to cancel the noise due to the leakage magnetic flux of the power transmission coil 3. The manufacturing method is such that a ring-shaped projection 51 that fits into the groove 21 of the power transmission core 2 and a ring-shaped projection 52 that fits into the groove 41 of the signal transmission core 4 are concentrically provided on the upper surface of the cylindrical die 50. A mold is used in which the holder 60 is fitted to the side surface of the die 50 and the upper surface of the holder 60 is covered with the injection plate 70. In advance, the noise canceling coil 6 is temporarily fixed to the bottom surface of the signal transmission core 4 with an adhesive or the like, and the ring-shaped projection 52 of the die 50 is fitted into the groove 41 of the signal transmission core 4 to form the die 50. Power transmission core 2 on the ring-shaped protrusion 51 of
The groove 21 is fitted, the holder 60 is fitted to the side surface of the die 50, the upper surface of the holder 60 is covered with the injection plate 70, and the resin is injected under pressure from the injection nozzle 71. After the resin is solidified, the injection plate 70 is removed, the die 50 is pushed upward, the holder 60 and the die 50 are released, and the remaining transformer primary side 10 or transformer secondary side 20 on the die 50 is removed. .

[0056]

By the above means, in the apparatus, most of the magnetic flux generated by the power transmission coil 3 and the signal transmission coil 5 on the primary side and the secondary side is in the power transmission core 2 and the signal transmission core 4. Flow individually. However, when a part of the magnetic flux generated by the power transmission coil 3 leaks to the outside of the power transmission core 2, the leaked magnetic flux interlinks with the signal transmission coil 5 to induce a voltage and become noise. On the other hand, the noise canceling coil 6 of the reverse winding is connected in series to the signal transmitting coil 5, and the voltage induced in the noise canceling coil 6 by the leakage magnetic flux from the power transmitting coil 3 becomes a signal. The voltage induced in the transmission coil 5 is canceled. Further, since the noise canceling coil 6 is outside the signal transmitting core 4, it does not affect the magnetic flux of the signal transmitting core 4. In the manufacturing method, the frame 1, the power transmission core 2, the signal transmission core 4 are used.
The noise canceling coil 6 is integrally formed of resin, and the surfaces of the power transmission core and the signal transmission core are flush with each other.

[0086]

Embodiment An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a front sectional view showing an embodiment. A ring-shaped groove 11 is provided in a cylindrical non-magnetic member, and a ring-shaped power transmission with a U-shaped cross section is provided on the outer diameter side of the cylindrical portion 12 of the frame 1 in which the cylindrical portion 12 is provided at the center. For core 2
Are fitted and fixed. A ring-shaped power transmission coil 3 is housed in the ring-shaped groove 21 of the power transmission core 2. The top surface of the frame 1 is provided with one radial hole in which the lead 3L coated with the protective tube 3P and the lead 6L coated with the protective tube 6P are inserted.
The frame 1 may be manufactured in advance as a single component or integrally formed by resin molding. The cylindrical portion 12 of the frame 1 is provided with a circular groove 13 concentrically with the groove 21. A ring-shaped groove 64 is provided at the bottom of the groove 13. A ring-shaped signal transmission coil 5 is provided in the groove 13.
A ring-shaped signal canceling coil 6 having a number of turns substantially equal to that of the signal-transmitting coil 5 is housed in the ring-shaped groove 64, which houses the ring-shaped signal-transmitting core 4. It is housed so as to link with the magnetic flux created by 3. The signal transmission coil 5 and the noise cancellation coil 6 are connected in series. The groove 64 may be omitted when the frame 1 is integrally formed by resin molding. The lead 3L of the power transmission coil 3 and the lead 6L of the noise canceling coil 6 are provided outside the frame 1 at appropriate positions. The transformer primary side 10 is configured as described above, and the transformer secondary sides 20 having the same configuration are opposed to each other through the gap G. In the case of the rotary transformer type, the transformer primary side 10
Alternatively, one or both of the transformer secondary side 20 is rotated.

The operation will be described below. When the power transmission coil 3 and the signal transmission coil 5 on the primary side are energized, most of the magnetic fluxes created by the coils 3 and 5 individually flow in the power transmission core 2 and the signal transmission core 4. However, when a part of the magnetic flux generated by the power transmission coil 3 leaks to the outside of the power transmission core 2, the leaked magnetic flux interlinks with the signal transmission coil 5 to induce a voltage and become noise. On the other hand, since the noise canceling coil 6 of the reverse winding is connected in series to the signal transmitting coil 5, the voltage induced in the noise canceling coil 6 by the leakage magnetic flux from the power transmitting coil 3 is generated. , Cancel the voltage induced in the signal transmission coil 5.

The manufacturing method will be described below. As one of the manufacturing methods of the transformer primary side 10 and the transformer secondary side 20, the power transmission core 2 in which the power transmission coil 3 is housed in the frame 1 and the signal transmission core in which the signal transmission coil 5 is housed There is a method in which 4 are fitted and assembled, and each facing surface is ground to obtain flatness. Here, a manufacturing method of integrally molding with a mold having higher productivity will be described with reference to FIG. FIG. 2 is a front sectional view of the mold. The groove 2 of the power transmission core 2 is provided on the upper surface of the cylindrical die 50 having an outer diameter slightly larger than that of the power transmission core 2.
A ring-shaped projection 51 that fits into the groove 1 and a ring-shaped projection 52 that fits into the groove 41 of the signal transmission core 4 are concentrically provided. A ring-shaped holder 60 is fitted on the side surface of the die 50. A through hole 61 is provided at the center of the holder 60. The height of the holder 60 is such that when the die 50 is fitted, the depth of the groove is deeper than the height of the power transmission core 2, and when fitted, it is located at an appropriate position slightly higher than the upper surface of the die 50. Further, an ejection nozzle 63 in the radial direction is provided. On the upper surface of the holder 60, one groove 62 is provided in the radial direction in which the protective tubes 3P and 6P of the power transmission coil 3 are tightly inserted. Holder 6
The upper surface of 0 is covered with an injection plate 70 provided with an injection nozzle 71 in the approximate center.

The molding procedure will be described below step by step. In advance, the noise canceling coil 6 is connected in series to the bottom surface of the signal transmitting core 4 and is temporarily fixed directly or through the stay 9 with an adhesive or the like. Step 1: On the ring-shaped protrusion 52, the signal transmission core 4
Fit the groove 41 of. Step 2: The power transmission core 2 is attached to the ring-shaped protrusion 51.
Fit the groove 21 of. Step 3: Fit the holder 60 on the side surface of the die 50. Step 4: In the groove 62 of the holder 60, the leads 3L and 6
Tighten the protective tubes 3P and 6P with L inserted. Step 5: The upper surface of the holder 60 is covered with the injection plate 70 to firmly fix the die 50, the holder 60 and the injection plate 70. Step 6: Resin is injected under pressure from the injection nozzle 71. At this time, the surfaces of the power transmission core 2 and the signal transmission core 4 are exposed to the die 50 by injection pressure.
To maintain the same plane. After the resin solidifies, Step 7: Remove the injection plate 70. Step 8: The die 50 is pushed up and the holder 6
The die 0 and the die 50 are released. At this time, the resin remaining in the ejection nozzle 63 is cut. Step 9: Remaining transformer primary 1 on die 50
0 or the secondary side 20 of the transformer is removed. As described above, since it is integrally formed by molding, the productivity is high, and the surfaces of the power transmission core 2 and the signal transmission core 4 are accurately formed on the same plane as the upper surface of the die 50.

FIG. 3 shows a second embodiment. In this example, the terminal 81 in which the leads 3L and 6L of the example are provided on the substrate 8
Concentrate on the connection to facilitate connections from the outside. (1) When the frame 1 is manufactured as a single component in advance, a hole for inserting each lead is provided in the axial direction of the frame 1, each lead is inserted, and the leads 3L, 6L are inserted on the upper surface of the frame 1 connecting the holes. Groove is formed in the direction perpendicular to the axis,
The leads 3L and 6L are connected to the terminal 81 on the bottom surface of the substrate 8. (2) When the frame 1 is integrally formed with other components by resin, the board 8 is provided with a hole 82 through which the injection nozzle 71A is inserted, and a plurality of stays 9 are provided between the upper surface of the power transmission core 2 and the bottom surface of the board 8. After connecting each lead to the terminal 81 on the back surface of the substrate 8, the substrate 8 is supported by the stay 9, and the resin is provided between the substrate 8, the power transmission core 2, the signal transmission core 4 and the noise premature coil 6. To mold.

The manufacturing method will be described below. In the case of the above (1), the respective parts may be assembled in order, and the description thereof will be omitted. A front sectional view of the mold in the case of (2) above is shown in FIG. The difference from the mold of FIG. 2 lies in the structure of the injection plate. The injection plate 71A is provided with an injection nozzle 71A at a position matching the hole 82 formed in the substrate 8,
A groove 72 for masking the terminal 81 is provided. The manufacturing procedure is the same as the manufacturing method according to the embodiment up to step 3. After that, follow the steps below. Step 4: Connect the leads 3L and 6L to the terminal 81 on the back surface of the substrate 8. Step 5: Temporarily fix the stay 9 on the upper surface of the power transmission core 2. Step 6: The substrate 8 is placed on the stay 9 and the surface thereof is the holder 60.
Set so that it matches the upper surface of. Step 7: Inject the injection nozzle 71A to the substrate 8
The upper surface of the holder 60 is covered with the injection plate 70A so as to match the hole 82 provided in the die 50,
The holder 60 and the injection plate 70A are firmly fixed. Step 8: The resin is injected under pressure from the injection nozzle 71A. After the resin has solidified, Step 9: Remove the injection plate 70A. Step 10: The die 50 is pushed upward and the holder 60 and the die 50 are released. Step 11: Remaining on the die 50, the transformer primary side 10 or the transformer secondary side 20 integrally forming the substrate 8
Remove. As a result, the substrate having the external connection terminal and the transformer are integrally molded.

[0112]

The above-mentioned structure has the following effects. (1) In the device, since the voltage induced in the noise canceling coil cancels the voltage induced in the signal transmitting coil, the transmission of an erroneous signal is almost completely eliminated and the reliability is further improved. (2) In the resin molding manufacturing method, since each component is integrally formed, the productivity is improved, and the surfaces of the power transmission core and the signal transmission core are flush with each other, which requires finishing. Disappear.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2 is a front sectional view showing a mold for manufacturing the embodiment of the present invention.

FIG. 3 is a front sectional view showing a second embodiment of the present invention.

FIG. 4 is a front sectional view showing a mold for manufacturing the second embodiment of the present invention.

[Explanation of symbols]

 1 Frame 11, 13, 21, 41, 62, 64, 72 Groove 12 Cylindrical Part 2 Power Transmission Core 3 Power Transmission Coil 3L, 6L Leads 3P, 6P Protection Tube 4 Signal Transmission Core 5 Signal Transmission Coil 6 Noise Offset coil 10 Transformer primary side 20 Transformer secondary side 50 Dies 51, 52 Ring-shaped projection 60 Holder 61 Through hole 63 Ejection nozzle 70, 70A Injection plate 71, 71A Injection nozzle 8 Substrate 81 Terminal 9 Stay

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuhiko Kiba No. 2 Kurosaki Shiroishi, Yawatanishi-ku, Kitakyushu, Fukuoka Prefecture Yasukawa Electric Co., Ltd. Yasukawa Electric Co., Ltd.

Claims (8)

[Claims] 1. A power transmission core having a power transmission coil housed in a ring-shaped groove and a signal transmission core having a signal transmission coil housed in another ring-shaped groove are concentrically arranged. In a non-contact power and signal transmission device in which a pair of flat cylindrical transformer cores are opposed to each other with a gap, magnetically separate the power transmission core and the signal transmission core, and the power transmission core A non-contact power and signal transmission device comprising a non-magnetic frame for accommodating the signal transmission core. 2. The contactless power and signal transmission device according to claim 1, wherein the frame is made of resin, and the power transmission core and the signal transmission core are integrally molded. 3. A noise canceling coil having a reverse winding to the signal transmitting coil, which is linked to the magnetic flux generated by the power transmitting coil, is provided outside the periphery of the signal transmitting core, and the signal canceling coil is provided. The contactless power and signal transmission device according to claim 1, wherein the noise canceling coil is connected in series to the coil. 4. The contactless power and signal transmission device according to claim 3, wherein the frame is made of resin, and the power transmission core, the signal transmission core and the noise canceling coil are integrally molded. 5. The contactless power and signal transmission device according to claim 2, wherein a lead for connection is drawn out from a side surface of the frame. 6. The contactless power and signal transmission device according to claim 2, further comprising a substrate provided with a connection terminal on an upper surface of the frame. 7. A ring-shaped projection that fits into the groove of the power transmission core and a ring-shaped projection that fits into the groove of the signal transmission core are concentrically provided on the upper surface of the cylindrical die, and the ring-shaped projection is provided on the side surface of the die. A mold is used in which the holder is fitted and the top surface of the holder is covered with an injection plate.The noise canceling coil is temporarily fixed to the bottom surface of the signal transmission core in advance with an adhesive or the like, and the ring of the die is used. The groove of the signal transmission core and the groove of the power transmission core are fitted to each of the protrusions, the holder is fitted to the side surface of the die, and the lead is tightly fitted in the groove provided on the upper surface of the holder. Set, cover the upper surface of the holder with the injection plate,
After the resin is injected under pressure from the injection nozzle and the resin is solidified, the injection plate is removed, the die is pushed upward and the holder and the die are released, and the non-contact power remaining on the die And a method for manufacturing a contactless power and signal transmission device, which comprises removing the signal transmission device. 8. A hole for inserting an injection nozzle is provided in the substrate, a groove for masking a terminal of the substrate is provided in the injection plate, and a resin is temporarily supported by a stay between the substrate and the core for power transmission. The method for manufacturing a contactless power and signal transmission device according to claim 7, wherein pressure injection is performed.