JP2008126678A - Non-contacting feeding system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve feeding efficiency by allowing an air gap to be narrowed. <P>SOLUTION: Litz wire 2 is united with a non-magnetic supporting element 10 by a band 12 to be a feeding cable 14. Tension is added to the supporting element 10 to reduce sagging, and the cable 14 is inserted in a receiving core 16. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a system that performs non-contact power supply to a transfer device, a robot, and the like, and particularly relates to improvement of power supply efficiency.

It is known that non-contact power feeding is performed in a transfer device or a robot used in a clean room or the like in order to avoid dust generation (for example, Patent Document 1). FIG. 7 shows a main part of the conventional non-contact power supply system. Reference numeral 2 denotes a litz wire as a power supply line, which is supported by a holder 4 made of plastic or the like and passes through the power receiving core 6. The power receiving core 6 is made of a magnetic material. For example, a power receiving coil (not shown) is wound around the side portions 7 and 7 so that the arm 5 of the holder 4 is released from the air gap 8. If there is a wide air gap 8 in the power receiving core 4, power supply efficiency is reduced. Ideally, the width of the air gap 8 only needs to prevent the magnetism due to the magnetic field from the litz wire 2 from being saturated, and the air gap 8 of the width of the arm 5 is too wide. Therefore, the inventor studied to support the litz wire 2 without using the arm 5.
JP 2003-63613 A

An object of the present invention is to eliminate the necessity of providing a large air gap in a power receiving core and to improve power supply efficiency in a non-contact power supply system.
The additional subject in the invention of Claims 2-4 is providing the specific structure of the support body of a feeder.

  The present invention is a system for performing non-contact power feeding by passing a power supply line through a power receiving core, which is arranged in parallel with the power supply line within a range where power is supplied, and whose position is fixed on both outer sides of the power supply range. The power supply line is supported by the support body, and the power supply line and the support body are both disposed so as to pass through the power reception core, and the width along the longitudinal direction of the power supply line of the air gap provided in the power reception core is set. Further, the support body and the feeder line are narrower than the above.

Preferably, the support is insulating and nonmagnetic.
Preferably, the supply line and the support are suspended from each other by applying tension to the support from both outer sides of the power supply range.
Preferably, the power supply line and the support are incorporated in one cable.

  In the present invention, the power supply line is supported by the support, and the support may be supported by fixing the position on both outer sides of the power supply range. For this reason, the holder arm for supporting the power supply line is unnecessary, and the air gap of the power receiving core can be narrowed or eliminated. When the air gap is narrowed, the magnetic coupling between the power supply line and the power receiving core can be increased, and the power supply efficiency is improved.

When the support is insulative and non-magnetic, power loss due to eddy current or the like in the support can be prevented, and power supply efficiency can be prevented from being reduced due to a magnetic field confined in the support.
Furthermore, when tension is applied to the support from both outer sides of the power supply range, the support can be prevented from drooping.
In addition, when the power supply line and the support are incorporated in one cable, a cable in which the power supply line and the support are integrated may be provided, and the handling becomes easy.

  In the following, an optimum embodiment for carrying out the present invention will be shown.

  1 to 6 show a non-contact power feeding system and a modification thereof according to the embodiment. In each figure, 2 is a litz wire, which is an example of a feeder line, for example, a copper stranded wire. Reference numeral 10 denotes a support, which is made of, for example, ceramics or high-strength plastic, and is particularly suitable for highly oriented high-toughness crystalline plastic, that is, so-called engineering plastic, which has a round bar shape, a square shape, or a cylindrical shape. A rib or the like may be provided to prevent deformation caused by drooping due to gravity. Reference numeral 12 denotes a band which is used to couple the support 10 and the litz wire 2, and it is not always necessary to use the band 12 to support the litz wire 2 with the support 10. For example, the litz wire 2 is attached to the support 10. It may be fused or litz wire may be dispersed in the support 10.

  When the support 10 is made of plastic, an engineering plastic such as an aramid resin is preferable, and the droop is reduced by applying a large tension to the plastic having a high tensile strength. On the other hand, when the support 10 is made of ceramics, the droop is reduced by utilizing the high rigidity. Since long ceramics are difficult to manufacture, for example, a unit of a support is provided for each predetermined length, and they are fitted and bonded together. The support 10 and the band 12 are both insulative and nonmagnetic, for example, insulative and diamagnetic other than antiferromagnetic, so that no eddy current is generated by the magnetic field from the litz wire 2 and no magnetic field is contained. . The litz wire 2, the support 10, and the band 12 are collectively referred to as a feeding cable 14. The term “cable” here refers to the fact that the litz wire 2, the support 10, and the band 12 are combined rather than the litz wire 2 being covered by the support 10.

  The power receiving core 16 is cylindrical and made of a magnetic material. For example, a power receiving coil (not shown) is wound around both side surfaces 17 and 17 of the power receiving core 16 to receive power using a magnetic field from the litz wire 2. Reference numeral 18 denotes an air gap, which is not limited to the upper part of the power receiving core 16 but may be the bottom or side surface, and is provided to prevent the magnetism due to the magnetic field from the litz wire 2 from being saturated in the power receiving core 16. The width of the air gap 18 is a direction perpendicular to the longitudinal direction of the litz wire 2, in other words, in the width direction or height direction of the power receiving core 16, which is narrower than the width of the power feeding cable 14, more preferably the width of the support 10. Narrower than any of the widths of the litz wire 2. For this reason, the air gap 18 does not prevent the magnetic circuit from being formed in the power receiving core 16 and improves the power feeding efficiency.

  The support body can have various shapes other than that shown in FIG. 1. In the power supply cable 20 shown in FIG. 2, the litz wire 22 is disposed around the core-like support body 24 in a sheath shape. In the power supply cable 30 of FIG. 3, the litz wire 32 is arranged in a core shape, and the support 34 is arranged in a sheath shape around the litz wire 32. The shape of the power feeding cable is arbitrary, and for example, the litz wire may be dispersed in a support resin such as an aramid resin molded into a rod shape or a pipe shape.

  FIG. 4 shows an example in which contactless power feeding is performed to the stacker crane 42 using the power feeding cable 14 of the embodiment. Reference numerals 40 and 40 denote struts on both the left and right sides. Within this range, the stacker crane 42 receives power from the power supply cable 14, and the space between the struts 40 and 40 is a power supply range to the stacker crane 42. The litz wire 2 and the support body 10 are separated outside the support columns 40, 40, the support body 10 is fixed to the anchor 41, and tension is applied. Here, the litz wire 2 and the support 10 are separated and tension is applied only to the support 10, but tension may be applied while these are integrated.

  The stacker crane 42 is provided with a mast 44, and a lifting platform 46 having a transfer device is moved up and down, and the power receiving core 48 is moved up and down along the mast 44. When the power receiving core 48 is shown in FIG. 5, the basic structure is the same as that of the power receiving core 16 of FIG. 1. The power receiving core 48 is attached to the belt 50 and is moved up and down along the mast 44 by a belt drive motor (not shown). A height adjustment sensor 52 is provided on both the front and rear sides of the power receiving core 48, detects a change in the height of the power feeding cable 14 in front of the stacker crane 42 in the traveling direction, and moves the power receiving core 48 up and down by the belt 50. In other respects, the power receiving core 48 is equivalent to the power receiving core 16 of FIG.

  FIG. 6 shows a modification regarding the height adjustment of the power receiving core. Arms 60 and 60 are provided before and after the power receiving core 16, and an insulating and nonmagnetic roller 61 is disposed on each of the arms 60 and 60 to support the power feeding cable 20. The power receiving core 16 is biased upward by a spring 62 so as to be movable up and down within the range of the guide 63. As a result, the drooping of the power feeding cable 20 is limited by the spring 62 and the power receiving core 16 is moved up and down according to the drooping of the power feeding cable 20. The roller 61 is in contact with the power supply cable 20, but this contact is rolling friction, and does not need to be as reliable as when a large current is stably received, and the contact pressure can be reduced. Therefore, dust generation can be made relatively small.

In the embodiment, the following effects can be obtained.
(1) Since the air gap of the power receiving core can be narrowed, the power feeding efficiency can be improved.
(2) If a nonmagnetic and insulating material is used for the support, loss due to eddy currents and magnetic field containment will not occur.
(3) Dripping can be restricted by applying tension to the power supply cable or support from both sides of the power supply range.
(4) If the support is made of high-strength plastic, a large tension can be applied and the droop can be made relatively small.
(5) If the support is made of insulating and non-magnetic ceramics, the droop can be reduced because of the large rigidity.
(6) If a mechanism for adjusting the height of the power receiving core according to the drooping of the feeding cable is provided on the side of the transfer device such as a stacker crane or the robot, the drooping of the feeding cable can be handled.

Sectional drawing which shows a receiving core, a litz wire, and a support body in the non-contact electric power feeding system of an Example The figure which shows the litz wire and the support body in the modification The figure which shows the litz wire and support body in a 2nd modification The figure which shows the example which applied the non-contact electric power feeding of an Example to a stacker crane The figure which shows the raising / lowering mechanism of the receiving core in an Example The figure which shows the height holding mechanism of the electric power feeding cable in a 3rd modification. Sectional view of power receiving core and litz wire in the conventional example

Explanation of symbols

2 Litz wire 4 Holder 5 Arm 6, 16 Power receiving core 7, 17 Side portion 8, 18 Air gap 10 Support body 12 Band 14 Power supply cable 20, 30 Power supply cable 22, 32 Litz wire 24, 34 Support body 40 Strut 41 Anchor 42 Stacker crane 44 Mast 46 Lift platform 48 Power receiving core 50 Belt 52 Height adjustment sensor 60 Arm 61 Roller 62 Spring 63 Guide

Claims (4)

A non-contact power supply system in which a power supply line passes through a power receiving core, and is arranged in parallel with the power supply line within a power supply range and fixed at positions outside the power supply range. The power supply line is supported, and both the power supply line and the support are disposed so as to pass through the power receiving core, and the width of the air gap provided in the power receiving core along the longitudinal direction of the power supply line is set to the support. And the non-contact electric power feeding system characterized by making it narrower than any of the said electric power feeding line. The contactless power feeding system according to claim 1, wherein the support is insulative and nonmagnetic. 3. The non-contact power feeding according to claim 1 or 2, wherein the supply line and the support are suspended from each other by applying tension to the support from both outsides of the power feeding range by the power feeding line. system. The non-contact power feeding system according to claim 1, wherein the power feeding line and the support are incorporated into one cable.

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