JP2000164440A - Electric power transmitter and rotary joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric power transmitter which can efficiently transmit electric power from a stationary side to a rotating side and a rotary joint provided with the transmitter. SOLUTION: A ferrite core coil unit 18 is formed by housing a bobbin 52 wound with a formal wire 52 by a prescribed number of turns in a pot-type ferrite core 50 and the unit 18 is stuck to an annular supporting plate 15b formed of a nonmagnetic material, such as the stainless steel, etc. Then two ferrite core coil unit rings composed of ferrite core coil units 18 formed in the above-mentioned way and supporting plates are attached to the stationary side and rotating side of an electric power transmitter in a state where the rings are faced oppositely to each other at a prescribed interval so that the transmitter may transmit electric power in a non-contacting state by the action of electromagnetic induction. In addition, the number of ferrite core coil units on the rotating side is made smaller than that of the coil units on the stationary side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a power transmission device for transmitting power in a non-contact manner and a rotary joint provided with the power transmission device.

[0002]

2. Description of the Related Art Conventionally, in order to supply power to a rotating body, a slip ring having a structure in which a stationary brush contacts a rotating ring has been used.

However, the slip ring has a large frictional resistance to the brush ring, which hinders the rotation of the rotating body at a high speed. In addition, the contact portion between the brush and the ring is worn, so that the brush or the ring is worn. It had to be replaced regularly.

Therefore, a method of transmitting power in a non-contact manner using electromagnetic induction has been considered. According to this method, there is no problem of frictional resistance or a problem of wear of the contact portion, and it is expected that power can be favorably supplied to the rotating body.

However, in order to efficiently transmit power without contact using electromagnetic induction,
Although it is necessary to reduce the leakage of the magnetic flux, there has been no power transmission device that is non-contact and can prevent the leakage of the magnetic flux.

As a device capable of transmitting power efficiently using electromagnetic induction, a transformer using a pot type ferrite core is well known. For example, a rotary joint is provided with a hollow portion for cooling water. In this case, the diameter of the hollow portion of the pot type ferrite core needs to be larger than the diameter of the hollow portion for cooling water. However, the ferrite core is a fired product and is distorted or warped during the manufacturing process. Such phenomena appear more conspicuously as the size of the core increases, and the amount of deformation increases. Therefore, the large core has a problem that the yield is poor. Furthermore,
If the amount of deformation in the manufacturing process is large, post-processing such as polishing is also required, which makes the product extremely expensive. Thus, it is very difficult to increase the size of the pot type ferrite core.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and can efficiently transmit power from the stationary side to the rotating side, and can be configured at low cost even when a hollow part having a relatively large diameter is used. It is an object to provide a rotary joint including a power transmission device.

[0007]

According to a first aspect of the present invention, there is provided a power transmission device comprising: a plurality of pot-shaped ferrite cores each having an annular recess formed therein; A ferrite core coil unit, comprising a pair of support members that are in contact with the bottom surface of the plurality of ferrite core coil units opposite to the surface on which the annular concave portion is formed and support the plurality of ferrite core coil units, On each of the pair of support members, the plurality of ferrite core coil units are annularly arranged at substantially equal intervals to form ferrite core coil unit rings having substantially the same diameter as each other, and the ferrite core coil unit rings of each other are coaxial. It is characterized in that they are opposed to each other with a predetermined gap, and are arranged to be rotatable relative to each other.

According to the power transmission device of the first aspect,
When a pulsed current is applied to the coil of the ferrite core coil unit in the ferrite core coil unit ring on the primary side, a magnetic flux that changes in accordance with the current is generated, and the magnetic flux passes through the inside of the pot type ferrite core. Since the ferrite core coil unit of the secondary side ferrite core coil unit ring is opposed to the ferrite core coil unit of the primary side ferrite core coil unit ring with a predetermined gap, The magnetic flux generated through the inside of the ferrite core passes through the inside of the pot type ferrite core on the secondary side. Therefore, the magnetic flux generated and changed on the primary side penetrates the coil housed in the annular concave portion of the pot-type ferrite core on the secondary side, and the secondary side coil induces an induction to prevent the change of the magnetic flux. Power is generated. As described above, according to the present invention, most of the magnetic flux passes through the inside of the pot-type ferrite cores on the primary side and the secondary side, so that the flux from the primary side to the secondary side efficiently with almost no leakage of the magnetic flux. Power transmission is performed in a non-contact manner. Moreover, the primary and secondary ferrite core coil unit rings are formed in an annular shape having substantially the same diameter as each other and are coaxially opposed so as to have a predetermined gap. Even when the unit rings are relatively rotated, each ferrite core coil unit forming the primary side and the secondary side ferrite core coil rings faces one of the ferrite core coil units while maintaining the predetermined gap. Thus, the efficient transmission of power is not impaired. Furthermore, since the pot type ferrite core is used in the present invention, the annular ferrite core coil unit ring can be easily formed to have a large diameter, and the hollow portion is effectively used by making the support member hollow. be able to.

According to a second aspect of the present invention, there is provided a power transmission device according to the first aspect, wherein the ferrite core coil forms the ferrite core coil unit ring on the surface of the support member. The number of units may be different for each of the ferrite core coil unit rings.

[0010] According to the power transmission device of the second aspect,
Since the number of the ferrite core coil units on the surface of the support member is different from each other, the relative positions of all the ferrite core coil units forming the ferrite core coil rings of each other are in a plan view parallel to the surface of the support member. There is no match so that they overlap completely. When the relative positions of all the ferrite core coil units match in this way, the gap between the adjacent ferrite core coil units also matches, so that in the region where the ferrite core coil units face each other, the leakage of magnetic flux is small. If the relative positions of the ferrite core coil units deviate from the coincident state, the relative positions of all the ferrite core coil units are simultaneously deviated from the coincident state. Until the relative positions of the units return to the coincident state at the same time, proper power transmission is not performed. In contrast,
Since the present invention does not allow the relative positions of all the ferrite core coil units in each other's ferrite core coil rings to completely overlap in a plan view parallel to the support member surface, any pair of ferrite core coil units can be used. Even when the relative position of the ferrite core coil unit is shifted, the relative positions of any other pair of ferrite core coil units are in the same state, and the induced electromotive force is continuously generated on the secondary side. Is generated. Therefore, there is no variation in the generated dielectric electromotive force, and power supply with little ripple is performed.

According to a third aspect of the present invention, in order to solve the above problem, the number of ferrite core coil units forming one ferrite core coil unit ring in the power transmission apparatus according to the second aspect is provided. Is N, the number of ferrite core coil units forming the other ferrite core coil unit ring is N-1.

According to the power transmission device of the third aspect,
The number of the ferrite core coil units on the surface of the support member forming one ferrite core coil unit ring, and the number of the ferrite core coil units on the surface of the support member forming the other ferrite core coil unit ring Because there is only one difference from
The increase in the gap between the adjacent ferrite core coil units in the other ferrite core coil unit ring forms the length of the ring connecting the centers of the respective ferrite core coil units to form the other ferrite core coil unit ring. Since a value obtained by dividing by the number of the ferrite core coil units is sufficient, a period in which no induced electromotive force is generated is suppressed as much as possible, and power transmission with little ripple is performed.

According to a fourth aspect of the present invention, there is provided a power transmission apparatus as set forth in the second aspect, wherein each of the ferrite core coil unit rings has a pot type having a different diameter. A ferrite core coil unit including a ferrite core is used.

[0014] According to the power transmission device of the fourth aspect,
The diameter of the pot type ferrite coil of each ferrite core coil unit forming one ferrite core coil unit ring is different from the diameter of the pot type ferrite coil of each ferrite core coil unit forming the other ferrite core coil unit ring. Therefore, the relative positions of all the ferrite core coil units in each other's ferrite core coil unit rings do not coincide so as to completely overlap in plan view parallel to the support member surface, and the relative positions are shifted. In this case, the period during which no induced electromotive force is generated on the secondary side does not increase. Moreover, since there is no need to thin out the ferrite core coil units, the gap between adjacent ferrite core coil units does not increase, and power transmission with little ripple can be performed while minimizing the period during which no induced electromotive force is generated. Will be

According to a fifth aspect of the present invention, there is provided a power transmission device according to any one of the first to fourth aspects, wherein the pot type ferrite cores are opposed to each other. Position detecting means for detecting a relative position, and power supply means for supplying power to the ferrite core coil unit forming the ferrite core coil unit ring on one of the support members, further comprising a power supply means, The ferrite core formed from the overlapping pot-type ferrite core only when it is detected that the relative positions detected by the position detecting means are at positions overlapping each other in a plan view parallel to the surface of the support member. Power is supplied to the coil unit.

According to the power transmission device of the fifth aspect,
A ferrite core coil formed from the overlapping pot-type ferrite core only when it is detected that the relative positions detected by the position detecting means are at positions overlapping each other in a plan view parallel to the surface of the support member. By supplying power to the unit, the power is efficiently transmitted without generating induced electromotive forces having different polarities in the ferrite core coil unit.

According to a sixth aspect of the present invention, in order to solve the above problem, the power transmission device according to any one of the first to fifth aspects, wherein the power transmission device is arranged such that the surface of the support member has The height of the ferrite core coil unit ring to the surface of each ferrite core coil unit is substantially constant.

According to the power transmission device of the sixth aspect,
Since the height of the surface of each ferrite core coil unit of the ferrite core coil unit ring with respect to the surface of the support member is substantially constant, a plurality of ferrite core coil units are annularly arranged at substantially equal intervals, and ferrites having substantially the same diameter as each other. When a core coil unit ring is formed and the ferrite core coil unit rings of each other are coaxially opposed to each other so as to have a predetermined gap, the gap reaches the end of the ferrite core coil unit arranged annularly. , Is maintained at a predetermined value, so that the characteristics of power transmission do not vary. Further, the gap is maintained at a predetermined value everywhere even when the ferrite core coil unit rings are relatively rotated with each other, so that the predetermined gap can be miniaturized. Therefore, power transmission efficiency is improved.

According to a seventh aspect of the present invention, there is provided a power transmission device according to any one of the first to sixth aspects, wherein the supporting member is a non-magnetic member. Characterized by being formed from

According to the power transmission device of the present invention,
Since the support member for supporting the ferrite core coil unit is formed of a non-magnetic member, the magnetic flux does not pass through the support member, and heat generation due to a change in the magnetic flux is reliably prevented.

According to another aspect of the present invention, there is provided a rotary joint, wherein a first housing member attached to a hollow shaft or integrally formed with the hollow shaft is provided on the first housing member. A second housing member rotatably mounted by a bearing, wherein each of the first housing member and the second housing member has a plurality of pot-shaped ferrite cores having an annular recess formed therein. A plurality of ferrite core coil units accommodating coils therein, and a support member that contacts the bottom surface of the plurality of ferrite core coil units opposite to the surface on which the annular concave portion is formed and supports the plurality of ferrite core coil units. Wherein each of the support members in the first housing member and the second housing member has the plurality of support members. The ferrite core coil units are annularly arranged at substantially equal intervals, and the ferrite core coil unit rings of the first housing member and the second housing member are formed to have substantially the same diameter. The ferrite core coil unit rings of the second housing member are coaxially opposed to each other with a predetermined gap therebetween, and are arranged so as to be rotatable relative to each other.

According to the rotary joint of the present invention, the pulse-like current is caused to flow through the coil of the ferrite core coil unit in the ferrite core coil unit ring on the primary side formed in the second housing member. A magnetic flux that changes according to the current is generated, and the magnetic flux passes through the inside of the pot type ferrite core. The ferrite core coil unit of the primary side ferrite core coil unit ring formed on the second housing member has a secondary ferrite core coil unit formed on the first housing member with a predetermined gap. Since the ring-shaped ferrite core coil units face each other with a predetermined gap, the magnetic flux generated through the inside of the primary-side pot-type ferrite core flows through the inside of the secondary-side pot-type ferrite core. Pass. Therefore, the magnetic flux generated and changed on the primary side is
An induced electromotive force is generated through the coil housed in the annular recess of the pot-type ferrite core on the secondary side so as to prevent a change in magnetic flux. As mentioned above,
According to the present invention, most of the magnetic flux passes through the inside of the pot-type ferrite cores on the primary side and the secondary side, so that leakage of the magnetic flux also occurs between the first housing member and the second housing member rotating with respect to each other. In a state where there is almost no power, power can be efficiently transmitted in a non-contact manner. Moreover, the primary and secondary ferrite core coil unit rings are formed in an annular shape having substantially the same diameter as each other and are coaxially opposed so as to have a predetermined gap. Even when the unit rings are relatively rotated, each ferrite core coil unit forming the primary side and the secondary side ferrite core coil rings faces one of the ferrite core coil units while maintaining the predetermined gap. Thus, the efficient transmission of power is not impaired. Further, since the pot type ferrite core is used in the present invention, the annular ferrite core coil unit ring can be easily formed to have a large diameter, and the hollow shaft formed integrally with the first housing member has a large diameter. Even when it is formed, it is possible to secure a power transmission path by a pair of ferrite core coil units on the outer periphery of the hollow shaft. Therefore, an extra space in the rotation axis direction of the rotary joint is omitted.

According to a ninth aspect of the present invention, there is provided a rotary joint according to the eighth aspect, wherein the first housing member and the second housing member have the hollow shaft. Antenna members each having a pattern formed on a substrate having a diameter larger than the outer diameter are provided, and the antenna members are arranged to face each other with a predetermined gap therebetween, and the ferrite core coil unit ring is provided on the substrate. The rotary joint according to claim 8, having a diameter different from an outer diameter of the rotary joint.

According to the rotary joint of the ninth aspect, in addition to the power transmission as described above, the signal transmission is performed by the antenna members provided on the first housing member and the second housing member. However, since the diameter of the divided ferrite core group forming the pair of ferrite core coil units is different from the diameter of the substrate on which the antenna member is formed, the pair of ferrite core coil units and the antenna member are mutually separated. Can be avoided, and free arrangement is possible. For example, they are arranged concentrically to reduce the length of the rotary joint in the direction of the rotation axis.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram showing a schematic configuration of an extrusion-type laminating machine using a rotary joint for transmitting measurement information as one embodiment of the present invention.

As shown in FIG. 1, the extrusion type laminating machine of the present embodiment is provided with a sheet supply section 20 for supplying PET as a base material. The PET 21 supplied from the sheet supply unit 20 reaches the laminating unit via the transport path 22 and is configured to face the T die 23 in the laminating unit. The molten polyethylene is supplied to the T die 23 from the upper hopper 24, and the polyethylene supplied from the T die 23 is applied on the PET 21. And PET
The polyethylene applied on 21 is immediately cooled by cooling roll 25 and adheres to PET 21. The sheet formed into two layers by such a lamination process is conveyed to a winding unit 27 via a conveying unit 26, and is wound by the winding unit 27.

In order to carry out good laminating processing in such a laminating machine, it is important to maintain the surface temperature of the cooling roll 25 at a predetermined value, and the following cooling roll 25 is used.

FIG. 2 shows a cooling roll 2 according to this embodiment.
5 is a partially broken perspective view showing a schematic configuration of No. 5; FIG. As shown in FIG. 2, a plurality of pipes 30 for supplying cooling water are arranged inside the roll, and a vapor phase of the working fluid is provided between the pipe 30 and the roll surface 31. The temperature at the roll surface end is only 5 to 8 ° C. lower than that at the intermediate portion. For example, if the surface temperature of the intermediate portion of the roll is 36 ° C, the end portion becomes 29 to 31 ° C.
Therefore, by setting this temperature to be equal to or higher than the dew point of the surrounding air, dew condensation by the cooling roll 25 can be completely prevented. In the present embodiment, the cooling roll 25 has a diameter of 600 mm and a length of 2000 mm.
mm, and the diameter of a rotating shaft connected to a rotary joint described later was 15 mm. The cooling water temperature is 1
5 ° C.

Further, since the surface 31 of the cooling roll 25 is not only uniform in temperature but also mirror-finished, the transparency of the sheet to be laminated is made uniform over the entire width.

In the cooling roll 25,
In order to maintain the surface temperature at a predetermined appropriate temperature, FIG.
As shown in (A), the resistance thermometer 11 made of platinum is embedded in the surface layer of the cooling roll 25, and the measurement information of the resistance thermometer 11 is transferred from the rotating side to the stationary side using the rotary joint 1 for transmitting measurement information. The surface temperature is maintained at a desired constant temperature by controlling the flow rate of the cooling water based on the measurement information. The cooling water is shown in FIG.
The pipe 30 is supplied through a cooling water supply rotary joint 33 shown in (A), passes through a hollow shaft provided in the measurement information transmission rotary joint 1, and further passes through a rotation shaft 32 of a cooling roll 25 to the pipe 30. Reach.

Hereinafter, the configuration of the rotary joint 1 for transmitting measurement information according to the present embodiment will be described with reference to FIGS.
This will be described in detail with reference to FIG.

FIG. 3A is a plan view showing the entire cooling roll unit to which the rotary joint 1 for transmitting measurement information and the rotary joint 33 for supplying cooling water according to an embodiment of the present invention are attached. ) Is FIG.
It is a top view which shows the comparative example compared with the cooling roll unit of (A). FIG. 4 is a cross-sectional view of a half of the rotary joint 1 for transmitting measurement information of the present embodiment from a rotation center axis, and a plan view of the other half. FIG. 5 is a block diagram showing an electrical connection relationship between each circuit, the antenna member, and the power transmission coupler in the rotary joint 1 for transmitting measurement information of the present embodiment. The rotation center axis L shown in FIG. 4 matches the rotation center axis L shown in FIGS. 3A and 3B.

As shown in FIG. 3A, a rotary joint 1 for transmitting measurement information according to the present embodiment
5 side shaft end 2a and rotary joint 3 for cooling water supply
A hollow shaft 2 having a shaft end 2b on the third side, rings 3a and 3b fitted to the outer periphery of the hollow shaft 2, and rings 3a and 3b
, A first housing member 4 having a flange portion 4a and a body portion 4b, bearings 5a and 5b, and bearings 5a and 5b.
5b, a second housing member 6 having a ring 6a, a flange portion 6b, and a cylindrical wall 6c supported by the first housing member 4, and a body portion 4b of the first housing member 4.
, A support plate 15c attached to the flange portion 6b of the second housing member 6, an electric circuit unit 12 supported by the support plate 15a, and a first plate supported by the support plate 15b. It includes a ferrite core coil unit 18 and a first antenna member 13, and a second ferrite core coil unit 19 and a second antenna member 14 supported by a support plate 15c.

The hollow shaft 2 is an iron shaft in which a hollow hole 2c is formed as a cooling water supply passage, has a maximum thickness of about 30 mm, and can withstand a water pressure of about 7 kg / cm ^2. Is configured. The shaft end 2 a of the hollow shaft 2 on the side of the cooling roll 25 is fitted to the rotating shaft 32 of the cooling roll 25, and is firmly attached to the rotating shaft 32 by a bolt 34 inserted into a bolt hole 2 d provided in the hollow shaft 2. It is attached. Therefore, when the cooling roll 25 is rotationally driven, the hollow shaft 2 is also rotationally driven. Further, a threaded portion 2e is formed on the other shaft end 2b,
The cooling water supply rotary joint 33 formed with a corresponding threaded portion can be screwed to the shaft end 2b.

Rings 3a, 3b made of stainless steel are provided on the outer periphery of the hollow shaft 2 near the shaft ends 2a, 2b.
Are fitted and attached. And this ring 3a,
When the first housing member 4 is fitted and attached to 3b, an air space 3c is formed between the first housing member 4 and the hollow shaft 2. When the cooling water having the above-mentioned temperature is supplied to the hollow hole 2c of the hollow shaft 2, dew condensation may occur on the outer surface of the hollow shaft 2, but the air layer 3c prevents the influence of the dew on the electric circuit and the like. .

The first housing member 4 is made of anodized aluminum and has a flange portion 4a and a body portion 4b. The inner ring of the bearing 5a is fitted into the flange 4a,
Is fitted with the inner race of the bearing 5b.

The second housing member 6 is also made of aluminum, and the surface of the cylindrical wall 6c is anodized. The ring 6a of the second housing member is fitted to the outer ring of the bearing 5a, and the flange 6b of the second housing member 6 is fitted to the outer ring of the bearing 5b. Therefore, when the hollow shaft 2 rotates with the rotation of the cooling roll 25, the first flange member 4 rotates with respect to the second flange member 6.

The body 4b of the first flange member 4 rotating in this way is provided with hollow disk-shaped stainless steel supporting plates 15a, 15b provided substantially perpendicular to the rotation center axis L. The electric circuit unit 1 is provided on the support plate 15a.
2, and a first antenna member 13 for signal transmission and a first ferrite core coil unit 18 are attached to the support plate 15b.

The electric circuit unit 12 comprises a power supply converter 7, a resistance temperature converter 8, an A / F converter 9 and an F signal transmitter 10 shown in FIG. Reference numeral 11 is electrically connected to the resistance temperature converter 8 in the electric circuit unit 12 via a cable and a connector (not shown). Further, the resistance temperature converter 8
Is the A / F converter 9, and the A / F converter 9 is the F signal transmitter 1.
The F signal transmitter 10 is electrically connected to the first antenna member 13.

The first antenna member 13 is a member in which a wiring pattern as an antenna terminal is formed on a ring-shaped printed circuit board, and is attached to a support plate 15b via a support 13a. The measurement information signal output from the F signal transmitter 10 is a signal frequency-modulated by a carrier frequency of 340 MHz, and is transmitted from the first antenna member 13 to a second antenna member 14 described later.

The first ferrite core coil unit 18 supported by the support plate 15b as a support member together with the first antenna member 13 has a coil in a ferrite core as described later. It is electrically connected to the power converter 7 in the electric circuit unit 12. An induced electromotive force is generated in the coil of the first ferrite core coil unit 18 by the action of mutual induction as described later, and the induced electromotive force is supplied to the power converter 7. Thereby, stable power is supplied to the resistance temperature converter 8, the A / F converter 9, and the F signal transmitter 10 constituting the electric circuit unit 12.

On the other hand, a hollow disk-shaped support plate 15c made of stainless steel is also attached to the flange portion 6b of the second housing member 6, and the support plate 15c is
The second antenna member 14 and the second ferrite core coil unit 19 are supported.

Similarly to the first antenna member 13, the second antenna member 14 is a member in which a wiring pattern as an antenna terminal is formed on a ring-shaped printed circuit board, and is attached to a support plate 15c via a support base 14a. ing. The second antenna member 14 is arranged to face the first antenna member 13 with a gap of 0.5 mm to 1 mm, and the first antenna member 13 rotates with the rotation of the first housing member 4. The signal to be transmitted is input by the second antenna member 14. The input signal is received by the receiver 40 on the stationary side as shown in FIG.
The signal is converted into a signal having an analog voltage value by the A converter 41 and used as measurement information.

The supporting plate 6d as a supporting member includes
A second ferrite core coil unit 19 is attached to face the first ferrite core coil unit 18. Second ferrite core coil unit 1
9 has a coil in the ferrite core, as described later, similarly to the first ferrite core coil unit 18, and this coil is electrically connected to the stationary power converter 42 as shown in FIG. Have been. The first ferrite core coil unit 18 and the second ferrite core coil unit 19 are opposed to each other with a gap of 0.5 mm to 1 mm. A magnetic field is generated in the ferrite core coil unit 19, and an induced electromotive force is generated in the first ferrite core coil unit 18 by the mutual induction.

As described above, the first ferrite core coil unit 18 and the second ferrite core coil unit 1
Numeral 9 denotes a power transmission coupler for transmitting power by electromotive force generated by mutual induction (electromagnetic induction). Each ferrite core coil unit uses a pot-type ferrite core as shown in FIG.

The ferrite coil 50 shown in FIG. 6 is obtained by hardening a ferrite powder and a binder in a mold by pressure and heat treatment, and is formed in a pot shape. The ferrite core 50 is provided with a hollow cylindrical shaft 51.
In the annular recess formed between the inner peripheral surface of the cylindrical side wall of the
The bobbin 52 is stored. Bobbin 52
Is a hollow cylindrical member with a flange formed of polyacetal or the like, and a formal wire 53 is wound around the outer peripheral surface of the cylinder a predetermined number of times. Ferrite core 5 of bobbin 52
Attachment to zero uses a synthetic rubber adhesive. For example, the adhesive is applied to one point on the inner bottom surface of the ferrite core 50, and the bobbin 52 around which the formal wire 53 is wound.
And bonding is performed at room temperature for about 12 hours. In this embodiment, the formal wire 53 of about 30 turns is used.
Is wound around the bobbin 52 as an air core coil, and the bobbin 52
Was mounted on a ferrite core 50 having a diameter of 30 mm to form a ferrite core coil unit.

Then, the ferrite core coil unit 18 (19) formed as described above is mounted on the support plate 15b using a two-part epoxy adhesive which can be bonded at a low temperature, as shown in FIG. , 15c.
When an adhesive that bonds at a high temperature is used, cracks and the like may occur in the pot-type ferrite core 50 that is a fired product at the time of cooling. However, in the present embodiment, it is possible to bond at a low temperature. Such cracks and the like do not occur.

In the rotating side support plate 15b,
Thirteen first ferrite core coil units 18 are annularly arranged as shown in FIG. The stationary support plate 1
In 5c, as shown in FIG. 9, 14 second ferrite core coil units 19 are annularly arranged. As described above, in the present embodiment, the number of the first ferrite core coil units 18 on the rotating side is reduced by one from the number of the second ferrite core coil units 19 on the stationary side. However, the first ferrite core coil unit 18
In both the first and second ferrite core coil units 19, the intervals between the respective ferrite core coil units are set at substantially equal intervals. In other words, the first ferrite core coil unit 18 on the rotating side is configured to have a wider interval between the ferrite core coil units than the second ferrite core coil unit 19 on the stationary side.

The pot-type ferrite core 50 used in the present embodiment is generally glued at two points with an epoxy adhesive 60 after being superimposed as shown in FIG. And is attached to a housing or the like using holding metal fittings 61 and 62 as shown in FIG. And since the pot type ferrite core 50 used in this way needs to reliably prevent leakage of magnetic flux when superimposed,
High surface processing accuracy and high dimensional accuracy. Therefore, FIG.
As shown in FIG. 9 and FIG. 9, the ferrite core coil units 18 each including the pot type ferrite core 50,
Even when the support 19 is arranged annularly on the support plates 15b and 15c, the height from the support plates 15b and 15c can be made uniform. As a result, even when the second ferrite core coil unit 19 is set to the primary side and the first ferrite core coil unit 18 is set to the secondary side, they are coaxially opposed as shown in FIG. Can be kept constant.

Since the support plates 15b and 15c are made of non-magnetic stainless steel as described above,
No heat is generated even when the magnetic flux changes, and the ferrite core coil units 18 and 19 are supported by the support plates 15b and 15c.
It does not leave.

In this embodiment, the stationary second ferrite core coil unit 19 is set as the primary side, and the pot type ferrite core 50 constituting the second ferrite core coil unit 19 has a biferral wound air core coil. 5
Attach 3a. A normally wound air-core coil 51 is mounted in the central recess 50a of the pot-type ferrite core 50 constituting the second side ferrite core coil unit 18 on the secondary side.

In the above configuration, when a deformed high-frequency voltage is applied from the stationary side with reference to a pulse-like waveform, a magnetic flux is generated around the coil 53a, and the magnetic flux is generated as shown in FIG. It passes through the inside of the pot-type ferrite core 50 on the rotation side, and further passes through the inside of the pot-type ferrite core 50 on the rotation side. Thereby, the rotation side coil 53
In b, an electromotive force is generated by the principle of mutual induction (electromagnetic induction), and power is transmitted. Note that a ripple-shaped power supply fluctuation occurs on the rotation side. In the present embodiment, the ripple-shaped power supply fluctuation is rectified and adjusted to a predetermined power supply voltage by a DC / DC converter or the like.

In this case, as shown in FIG. 13 (A), if the primary side and the secondary side coils are normally wound, the primary side signal is turned on / off, and as shown in FIG. 13 (B).
The power is transmitted at a frequency of around kHz, but in this case, the ratio of the stop time is high, and the transmission efficiency is deteriorated.

Therefore, in this embodiment, FIG.
As shown in (A), the primary side is bi-ferrule wound,
By turning the secondary side into a normal winding, the primary side is alternately turned on / off alternately, and as shown in FIG.
As a frequency around 0 kHz, the secondary side synthesizes this to increase the efficiency.

In order to obtain a desired induced electromotive force in a configuration in which a gap is provided between the stationary-side ferrite core coil unit 19 and the rotating-side ferrite core coil unit 18 in such a manner as described above, a desired induced electromotive force is required. It is important to set the size of the gap and the size of the deviation between the center axes to appropriate values. Therefore, in the present embodiment, as shown in FIG. 15, a pair of ferrite core coil units 19 and 18 are fixedly arranged, and a core gap, which is a gap between them, and a center axis of each other. An experiment was conducted to examine the relationship between input power and output power while gradually changing the core eccentricity, which is the deviation. The results of the experiment are shown in FIGS.

FIG. 16A shows a ferrite core unit when an input power of 30.8 W (14 V, 2.2 A) is applied to the ferrite core coil unit 19 and the core gap is changed from 0.3 mm to 1.5 mm. The result of detecting the output power of the coil unit 18 is shown. As shown in FIG. 16A, the output power tends to decrease as the core gap increases. In the present embodiment, 30.8 W (14 V,
When an input power of 2.2 A) was given, 5.96 W (1
1.0 V, 542 mA) to 5.24 W (10.2 V, 5
The core gap was set in the range of 0.5 mm to 1.0 mm so as to obtain an output power of 22 mA).

FIG. 16B shows a 30.8 W (14 V,
When an input power of 2.2 A) was given, 5.96 W (1
1.0 V, 542 mA)
After setting the core gap to 0.5 mm, the ferrite core coil unit 19 was supplied with 33.0 W (15 V, 2.2 V).
A) Input power of A) is given, and the core eccentricity is -1 mm to +1 mm
Shows the results of detection of the output power of the ferrite core coil unit 18 when the output power is varied in the range shown in FIG. Here, the negative direction and the positive direction of the core eccentricity are directions indicated by arrows in FIG. As shown in FIG. 16B, it was found that when the core eccentricity was about -1 mm to +1 mm, almost the same output power as in the case where there was no core eccentricity was obtained.

FIG. 16C shows a 30.8 W (14 V,
When an input power of 2.2 A) was given, 5.96 W (1
1.0 V, 542 mA)
After setting the core gap to 0.5 mm, the core eccentricity was set to zero, and the input power was 30.8 W (14 V, 2.2 A)
The figure shows the result of detecting the output power when the output power was varied in the range of ７４74.4 W (24 V, 3.1 A). FIG.
As shown in (C), the input power is 30.8 W (14 V,
2.2A) to 74.4W (24V, 3.1A), the output power becomes 5.96W (11.0V, 54A).
2 mA) to 16.28 W (21.5 V, 757 mA).
Thus, according to the power transmission coupler using the ferrite core coil unit of the present embodiment, the output power can be easily adjusted.

Next, the relationship between the number of ferrite core coil units on the rotating side and the stationary side in this embodiment will be described. In the present embodiment, since the number of ferrite core coil units is configured to be different between the rotating side and the stationary side, as shown in FIG. 8 or FIG.
The relative positions of the ferrite core coil units on the rotating side and the stationary side in plan view parallel to the surface of 15c do not coincide with each other so that all of them completely overlap. Therefore, even when the rotating ferrite core coil unit 18 rotates with respect to the stationary ferrite core coil unit 19, the stationary ferrite core coil unit 1
From the viewpoint of 9, the ferrite core coil unit 18 on the rotating side always faces any one of the ferrite core coil units 19. FIG. 17 (A), (B)
FIG. 4 is a view in which the ferrite core coil unit is linearly developed with the support plates 15b and 15c viewed from the side.
In the state shown in FIG. 17A, the first ferrite core coil unit 19 on the stationary side and the first ferrite core coil unit 18 on the rotating side face each other with zero core eccentricity. Even when the rotating ferrite core coil unit 18 rotates in the direction indicated by the arrow in FIG. 17A from this state, the stationary first ferrite core coil unit 19 and the rotating first ferrite core coil If the core eccentricity with the unit 18 is in the range of 1 mm, power transmission is performed in the same manner as in the state of the core eccentricity of zero. Furthermore, the first ferrite core coil unit 1 on the stationary side
9 and the first ferrite core coil unit 1 on the rotating side
Even if the core eccentricity with respect to the core 8 is rotated to be 2 mm, the rotation side ferrite core coil unit 18 is rotated with the fourteenth ferrite core coil unit 19 on the stationary side because the interval between them is set to 2 mm. Side 13
The second ferrite core coil unit 18 is opposed. Hereinafter, even if the ferrite core coil unit 18 on the rotating side rotates in the same manner, any one of the ferrite core coil units 19 on the stationary side and any one of the ferrite core coil units 18 on the rotating side always perform normal power transmission. They will be opposed within the range of possible core eccentricities. FIG. 17B shows a state where the first ferrite core coil unit 19 on the stationary side and the first ferrite core coil unit 18 on the rotating side are rotated such that the core eccentricity is 5 mm. In this state, the stationary side 1
The third ferrite core coil unit 19 and the twelfth ferrite core coil unit 18 on the rotating side face each other within a range of core eccentricity that allows normal power transmission.

On the other hand, the number of ferrite core coil units is the same on the rotating side and the stationary side, and as shown in FIG. 8 or FIG. 9, the rotating side and stationary side in plan view parallel to the surfaces of the support plates 15b and 15c. If all the ferrite core coil units on the side are completely overlapped with each other and their relative positions coincide with each other, for example, the ferrite core coil unit 18 on the rotating side rotates from the state shown in FIG. First ferrite core coil unit 1
9 and the first ferrite core coil unit 1 on the rotating side
When the core eccentricity between the first and second ferrite core coil units 19 and 2 is 2 mm or more, the first ferrite core coil unit 19 on the stationary side and the 14
If the core is not rotated until the core eccentricity between the second ferrite core coil units 18 is within -1 mm, there is no ferrite core coil unit pair that normally performs power transmission. For example, in FIG. 18B, the core eccentricity between the first ferrite core coil unit 19 on the stationary side and the first ferrite core coil unit 18 on the rotating side becomes 5 mm from the state shown in FIG. 18A. Although such a state of rotation is shown, none of the ferrite core coil pairs are opposed to each other in the range of the core eccentricity that allows normal power transmission.

However, as shown in FIG. 19 (B), in the case where the ferrite core coil unit 18 on the rotating side faces the separate ferrite core coil unit 19 on the stationary side by half at a time, the figure is changed. As shown in FIG. 19 (B), a magnetic flux is formed, and power is transmitted.
However, in this state, FIG.
As can be seen from comparison with (A), the pot type ferrite cores 5 of the individual ferrite core coil units 18 on the rotating side are shown.
The direction of the magnetic flux formed at 0 is opposite between the case of FIG. 19A and the case of FIG. 19B, and the polarity of the induced electromotive force varies.

Therefore, in the present embodiment, as shown in FIGS. 8 and 9, a pair of photodiodes 54 and a photosensor 55 are provided between the ferrite core coil units on the support plates 15b and 15c. Only when the relative position between the stationary-side ferrite core coil unit 19 and the rotating-side ferrite core coil unit 18 is at a position where the core eccentricity is -1 to +1 mm, the stationary-side ferrite core coil unit 19 It was configured to supply power to the power supply. The lights emitted from the photodiodes 54 are received by the photosensors 55, and the photosensors 55 output a current corresponding to the amount of received light. Therefore, the output currents are such that each core eccentricity is −
When a current corresponding to the amount of received light at the position of 1 to +1 mm is reached, power is supplied to the stationary side ferrite core coil unit 19.

As described above, according to the configuration of the present embodiment,
Power transmission can always be performed stably irrespective of the relative positions of the stationary side ferrite core coil unit 19 and the rotating side ferrite core coil unit 18, and
Power is supplied only when the core eccentricity is at a position of −1 to +1 mm, so that normal power transmission can always be performed.

In this embodiment, the case where the diameter of the pot type ferrite core forming the ferrite core coil unit is the same on the stationary side and the rotating side has been described. By changing the ferrite core coil units on the rotating side and the stationary side in a plan view parallel to the surfaces of the support plates 15b and 15c, it is possible to completely prevent the ferrite core coil units from completely overlapping. With this configuration, since it is not necessary to thin out the ferrite core coil units, it is possible to prevent an increase in the gap between adjacent ferrite core coil units, and to minimize the period during which no induced electromotive force is generated,
Power transmission with little ripple can be performed.

Further, according to the configuration of the present embodiment, since the individual ferrite core coil units are annularly arranged on the support plate, the entire ferrite core coil unit ring has a large diameter of 200 mm. can do. Therefore, as shown in FIG. 4, even when the hollow shaft 2 having a diameter of 90 mm is formed for the cooling water, the first ferrite core coil unit 1 is formed on the outer periphery of the hollow shaft 2.
8 and the second ferrite core coil unit 19 can be arranged, so that the arrangement space in the rotation axis direction of the cooling roll 25 can be given a margin.

Further, in the present embodiment, the first antenna member 13, the second antenna member 14, the first ferrite core coil unit 18 and the second ferrite core coil unit 19 are provided concentrically, so that they are further improved. The arrangement space in the rotation axis direction can have a margin. In this way, the power transmission coupler and the antenna member can be mixed in the same section because the signal transmission frequency of the antenna member is 340 MHz, whereas the power transmission frequency of the power transmission coupler is 20 kHz. This is because the frequencies are not higher than 30 kHz and do not interfere with each other.

Next, the operation of transmitting power and signals in the rotary joint 1 for transmitting measurement information of this embodiment will be described with reference to the block diagram of FIG.

A change in the resistance value of the resistance temperature detector 11 connected to the resistance temperature converter 8 via a rotation side connector (not shown) is converted into a current in the resistance temperature converter 8, and this current is converted into an A / F. In the converter 9, the signal is converted into a predetermined frequency pulse signal according to the value. In the present embodiment, a 1000 Ω resistor is used as the resistance temperature detector 11, and the output signal when converted into a current by the resistance temperature converter 8 is 4 ° for a temperature of 0 ° C. to 100 ° C. ~ 20m
A. The carrier frequency is 340 MH
z is used. And this frequency pulse signal is F
The signal is frequency-modulated in the signal transmitter 10 and transmitted from the first antenna member 13. In the present embodiment, the transmission rate is set to 2 Mbps. On the other hand, the signal transmitted in this manner is received by the stationary receiver 40 via the second antenna member 14, and is converted into a current by the F / A converter 41. Therefore, the surface temperature of the cooling roll 25 can be detected on the stationary side. in this way,
Since the signal transmission is performed via the non-contact first antenna member 13 and the second antenna member 14, accurate temperature detection can be performed without affecting the resistance value change of the resistance temperature detector 11. . Further, in the present embodiment, when the cooling roll 25 rotates at 1000 rpm, the rotating portion of the rotary joint 1 for transmitting measurement information also rotates at 1000 rpm. No temperature deterioration is possible, and good temperature detection is possible for a long period of time.

In the power converter 42 on the stationary side, 100 V AC is converted to 28 V DC, and the power is supplied at a frequency of 30 kHz to the bifilar-wound coil 51 in the second ferrite core coil unit 19 on the primary side. . As a result, a pulsed current flows through the coil 51 of the second ferrite core coil unit 19, and a magnetic flux that changes according to a change in the current passes through the coil 51 of the second ferrite core coil unit 19. Then, the change in the magnetic flux causes an induced electromotive force in the coil 51 of the first ferrite core coil unit 18 on the secondary side, and is supplied to the power converter 7. In the power converter 7, the DC 24
V and a voltage of ± 15 V DC and supplied to each circuit in the electric circuit unit 12. In the present embodiment, the rotating portion of the rotary joint 1 for transmitting measurement information rotates at a maximum of 1000 rpm. However, since power is supplied in a non-contact manner, no spark such as a slip ring is generated, and the solvent is not generated. No explosion in atmosphere. In addition, since there is no contact, there is no deterioration due to wear and the like, and good power supply can be performed for a long time.

The bearing 5a, the connector (not shown), and the like are all water-resistant. The first housing member 4 and the second housing member 6 are composed of the electric circuit unit 12, the power transmission coupler, and the antenna member. Is covered in a substantially sealed state, so that even if the rotary joint 1 of the present embodiment is used for the cooling roller 25 using cooling water, there is no danger of a failure of an electric circuit or the like due to water and a leakage accident.

As described above, in the present embodiment, while the power is supplied stably for a long period of time,
Since the measurement information of No. 1, that is, the change in the resistance value, is transmitted to the stationary side in a non-contact manner, accurate temperature detection is performed over a long period of time.

The excellent effects of the rotary joint 1 having the power transmission coupler according to the present embodiment as described above become clearer by comparing with the conventional power supply means. For example, the most common example of the means for supplying power to the rotating body is a slip ring. However, since the slip ring has a large frictional resistance, the slip ring has a maximum frictional resistance such as the rotary joint of the present embodiment. In a device that requires a rotation speed of 1000 rpm, it is not suitable because it hinders the increase of the rotation speed.
In addition, the contact portion of the slip ring is worn out over a long period of use, so that periodic replacement is required.

On the other hand, since the power transmission coupler of the present embodiment is of a non-contact type, it has no frictional resistance and can easily increase the number of revolutions. In addition, since it is a non-contact type, there is no wear and no replacement work is required.

A configuration in which a battery is provided inside the rotating body is also conceivable, but such a configuration requires periodic battery replacement and charging.

On the other hand, since the power transmission coupler of the present embodiment supplies power in a non-contact manner by using electromagnetic induction, there is no need to replace components.

It is also conceivable to use a large toroidal core and cut the inside to produce a large pot-type ferrite core. However, since the ferrite core is brittle, it is very difficult to perform cutting. It is. Therefore,
Conventionally, only a pair of small pot-type ferrite cores were used to form a power transmission coupler that was arranged in a non-contact and opposed manner.In a rotary joint for transmitting measurement information, this power transmission coupler was connected to an antenna member. It cannot be provided concentrically with the above, but must be provided in series. In addition, the rotary joint 35 for transmitting measurement information configured as described above has to be arranged at the shaft end of the cooling roll 25 behind the rotary joint 33 'for supplying cooling water as shown in FIG. 3B. I can't get it.

On the other hand, the power transmission coupler according to the present embodiment has a pot-type coupler by arranging a semi-cylindrical split ferrite core, which is originally used for a clamp filter for shielding a cable, in an annular shape. Since a large ferrite core having a similar shape can be formed, a power transmission coupler can be arranged on the outer periphery of the hollow shaft for cooling water. As a result, as is clear from the comparison between FIG. 3A and FIG. 3B, the entire length of the cooling roll unit including the rotary joint is set to the length W (about 300 mm in the example of FIG. 3B). Can be shortened. In addition, the entire length of the cooling roll unit of the present embodiment is longer than that of the conventional cooling roll unit by the amount of the rotary joint 1 for transmitting measurement information. Since it is configured to reduce the length, it is only about 100 mm longer than in the past. Therefore, in a system in which a cooling roll unit is stored in a rack using a crane or the like and the cooling roll unit is exchanged by being transported from the rack, a rack having the same size as the conventional one can be used. It can be used effectively.

Further, in the above-described embodiment, the case where the present invention is applied to the rotary joint for the cooling roll has been described. However, the present invention is not limited to this, and a fluid other than the cooling water or the like is provided in the hollow shaft. Or a rotary joint that supplies gas such as gas, or passes a thick cable or the like through a hollow shaft. In this case, a heat insulating material may be provided at the position of the air layer 3c depending on the situation. However, in particular, when the rotary joint for transmitting measurement information of the present invention is applied to a cooling roll using cooling water, since the above-described water-resistant treatment is performed, a particularly excellent effect is exhibited. is there.

In the above-described embodiment, the number of the pot type ferrite cores is 13 and 14 as an example.
Although the present invention is not limited to this, the present invention is not limited to this, and may be an appropriate number according to the size of the pot type ferrite core to be used or the size of the diameter of the power transmission coupler. Further, the number of turns of the coil is set to about 30 turns as an example, but the present invention is not limited to this.
It can be changed as appropriate.

[0080]

According to the power transmission device of the present invention, a plurality of ferrite core coil units each having a coil housed in a plurality of pot type ferrite cores are annularly mounted on each of a pair of support members at substantially equal intervals. Since the ferrite core coil unit rings having substantially the same diameter as each other are formed, and the ferrite core coil unit rings of each other are coaxially opposed so as to have a predetermined gap, and are arranged so as to be rotatable relative to each other. In addition, power can be efficiently transmitted from the primary side to the secondary side in a non-contact manner with almost no leakage of magnetic flux. Further, even when the pair of ferrite core coil units are relatively rotated, efficient power transmission can be performed. Further, the ferrite core coil unit ring can be easily formed to have a large diameter, and the hollow portion can be effectively used by making the support member hollow.

According to the power transmission device of the second aspect,
Since the number of the ferrite core coil units forming the ferrite core coil unit ring on the surface of the support member is different for each of the ferrite core coil unit rings, the relative positions of the ferrite core coil units are different. Therefore, the power supply can be stably transmitted regardless of the relative position of each ferrite core coil unit without being coincident so as to completely overlap in plan view parallel to the surface of the support member. Therefore, there is no variation in the generated dielectric electromotive force, and power transmission with little ripple can be performed.

According to the power transmission device of the third aspect,
When the number of ferrite core coil units forming one ferrite core coil unit ring was N, and the number of ferrite core coil units forming the other ferrite core coil unit ring was N-1, one of the ferrite core coil units was formed. The number of the ferrite core coil units on the surface of the support member forming the ferrite core coil unit ring and the number of the ferrite core coil units on the surface of the support member forming the other ferrite core coil unit ring Since the difference is only one, the increase in the gap between the adjacent ferrite core coil units in the other ferrite core coil unit ring is the length of the ring connecting the centers of the respective ferrite core coil units. The ferrite that forms the other ferrite core coil unit ring It requires on the order of a value obtained by dividing by the number of sites core coil unit, an induced electromotive force minimizing the generated non period, can be performed with less power transmission ripple.

According to the power transmission device of the fourth aspect,
In each of the ferrite core coil unit rings,
Since ferrite core coil units composed of pot-type ferrite cores having different diameters were used, the relative positions of all the ferrite core coil units in each other's ferrite core coil unit rings were in a plan view parallel to the support member surface. It is possible to prevent the period in which the induced electromotive force is not generated on the secondary side from becoming long even when the relative positions deviate from each other because they do not coincide so as to completely overlap. In addition, since there is no need to thin out the ferrite core coil units, it is possible to prevent an increase in the gap between adjacent ferrite core coil units. It can be performed.

According to the power transmission device of the fifth aspect,
The overlapping pot only when it is detected that the relative positions of the stationary side and the rotating side ferrite core coil units detected by the position detecting means are in positions overlapping each other in a plan view parallel to the surface of the support member. Since power is supplied to the ferrite core coil unit formed from the type ferrite core, generation of induced electromotive force with different polarities in the ferrite core coil unit can be reliably prevented, and efficient power transmission is achieved. It can be carried out.

According to the power transmission device of the sixth aspect,
Since the height from the surface of the support member to the surface of each ferrite core coil unit of the ferrite core coil unit ring is substantially constant, a plurality of ferrite core coil units are annularly arranged at substantially equal intervals, and are substantially mutually separated. Even if a ferrite core coil unit ring of the same diameter is formed and the ferrite core coil unit rings of each other are coaxially opposed to each other so as to have a predetermined gap, the gap of the ferrite core coil unit arranged annularly It can be kept at a predetermined value everywhere, and the occurrence of variations in the power transmission characteristics can be reliably prevented. Further, since the gap is maintained at a predetermined value everywhere even when the ferrite core coil unit rings are relatively rotated with each other, the predetermined gap can be miniaturized, and power transmission can be performed. Efficiency can be improved.

According to the power transmission device of the seventh aspect,
Since the support member is formed from a non-magnetic member, the magnetic flux does not pass through the support member, and heat generation due to a change in the magnetic flux can be reliably prevented.

According to the rotary joint of the present invention, a plurality of ferrite core coil units in which a coil is housed in a pot-type ferrite core in a support member disposed on each of the first housing member and the second housing member. Are arranged at substantially equal intervals in an annular shape, and the ferrite core coil unit rings of the first housing member and the second housing member are formed to have substantially the same diameter.
The ferrite core coil unit rings of the first housing member and the second housing member are coaxially opposed to each other so as to have a predetermined gap, and are disposed so as to be rotatable relative to each other. Power can be efficiently transmitted in a non-contact manner between the member and the second housing member with almost no leakage of magnetic flux. Further, the ferrite core coil unit ring can be easily formed to have a large diameter, and even if the hollow shaft formed integrally with the first housing member is formed to have a large diameter, a pair of ferrites is formed on the outer periphery of the hollow shaft. It is possible to secure a power transmission path by the core coil unit.
Therefore, an extra space in the rotation axis direction of the rotary joint can be omitted.

According to the rotary joint of the ninth aspect, the antenna member in which a pattern is formed on the first housing member and the second housing member on a substrate having a diameter larger than the outer diameter of the hollow shaft. And the antenna members are arranged to face each other with a predetermined gap therebetween, and the ferrite core coil unit ring is formed to have a diameter different from the outer diameter of the substrate, so that the pair of ferrite core coil units and the antenna Interference on the arrangement areas of the members can be avoided, and free arrangement is possible. For example, they can be arranged concentrically to reduce the length of the rotary joint in the direction of the rotation axis.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of an extrusion laminating machine according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a schematic configuration of a cooling roller used in the laminating machine of FIG.

FIGS. 3A and 3B are side views showing a state where a rotary joint is connected to the cooling roller of FIG. 2; FIG. 3A is a case where the rotary joint according to the first embodiment is provided; FIG.
FIG. 4 is a view showing a case where a rotary joint of a comparative example is provided.

FIG. 4 is a side view of a part of the rotary joint according to the embodiment of the present invention shown in FIG.

FIG. 5 is a block diagram showing an electrical connection relationship of a rotary joint according to an embodiment of the present invention.

FIG. 6 is a perspective view showing a ferrite core coil unit using a pot type ferrite core according to one embodiment of the present invention.

FIG. 7 is a cross-sectional view illustrating a method of attaching the ferrite core coil unit of FIG. 6 to a support plate.

FIG. 8 is a plan view showing a configuration of a ferrite core coil unit ring on a rotating side according to an embodiment of the present invention.

FIG. 9 is a plan view showing a configuration of a stationary side ferrite core coil unit ring according to the embodiment of the present invention.

FIG. 10 is a perspective view illustrating a conventional method of using a pot-type ferrite core.

FIG. 11 is a perspective view illustrating a conventional method of supporting a pot-type ferrite core.

FIG. 12 is a cross-sectional view for explaining a power transmission method of the power transmission coupler using the ferrite core coil unit according to one embodiment of the present invention.

13A is a diagram illustrating an example of a coil configuration in a transformer using electromagnetic induction as a comparative example, and FIG. 13B is a diagram illustrating a current waveform in the coil configuration of FIG.

14A is a diagram illustrating an example of a coil configuration of a power transmission coupler according to an embodiment of the present invention, and FIG.
FIG. 4 is a diagram showing a current waveform in the coil configuration of FIG.

FIG. 15 is a diagram illustrating a form of an experiment performed by varying the core gap and the core eccentricity between the ferrite core coil units of the power transmission coupler according to the embodiment of the present invention.

16A and 16B are diagrams showing the results of an experiment performed in the form of FIG. 15, wherein FIG. 16A shows the variation of output power when the core gap is varied with respect to a constant input power, and FIG. The figure which shows the fluctuation | variation of the output power when the gap and the input power are constant, and the core eccentricity is varied, (C) shows the fluctuation | variation of the output power when the core gap is fixed and the core eccentricity is zero and the input power is varied. FIG.

17 (A) and (B) are development views in the side direction showing changes in the relative positions of the rotating side and stationary side ferrite core coil units in one embodiment of the present invention.

FIGS. 18A and 18B are developments in the side direction showing changes in the relative positions of the ferrite core coil units on the rotating side and the stationary side in the comparative example.

FIG. 19 is a cross-sectional view showing a change in the relative position of the ferrite core coil unit on the rotating side and the stationary side in one embodiment of the present invention, where (A) is in a position where normal power transmission is possible, (B) is a sectional view showing a state in which an induced electromotive force is generated in a direction opposite to that of (A).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotary joint 2 ... Hollow shaft 4 ... 1st housing member 5a, 5b ... Bearing bearing 6 ... 2nd housing member 13 ... 1st antenna member 14 ... 2nd antenna member 15b, 15c ... Support plate 18 ... 1st ferrite core Coil unit 19 ... Second ferrite core coil unit 50 ... Pot type ferrite core 53 ... Formal wire (air-core coil) 54 ... Photodiode 55 ... Photosensor

Claims (9)

[Claims] 1. A plurality of ferrite core coil units each having a coil housed in each annular recess of a plurality of pot type ferrite cores having an annular recess formed therein, and a surface of the plurality of ferrite core coil units on which the annular recess is formed. A pair of support members that are in contact with the bottom surface on the opposite side and support the plurality of ferrite core coil units. The plurality of ferrite core coil units are annularly arranged at substantially equal intervals on each of the pair of support members. Forming a ferrite core coil unit ring having substantially the same diameter as each other, opposing each other so that the ferrite core coil unit rings have a predetermined gap on the same axis, and arranging them so as to be relatively rotatable relative to each other. A power transmission device characterized by the above-mentioned. 2. The ferrite core coil unit forming the ferrite core coil unit ring on the surface of the support member, wherein the number of the ferrite core coil units is different for each of the ferrite core coil unit rings. 1 power transmission device. 3. When the number of ferrite core coil units forming one ferrite core coil unit ring is N, the number of ferrite core coil units forming the other ferrite core coil unit ring is N.
The power transmission device according to claim 2, wherein the power transmission device is -1. 4. The power transmission device according to claim 2, wherein each of said ferrite core coil unit rings uses a ferrite core coil unit including pot-type ferrite cores having different diameters. 5. A power supply for supplying power to a ferrite core coil unit which forms the ferrite core coil unit ring on one of the support members, and a position detecting means for detecting a relative position of the pot type ferrite cores facing each other. Supply means, the power supply means only when it is detected that the relative positions detected by the position detection means are at positions overlapping each other in a plan view parallel to the surface of the support member. The power transmission device according to any one of claims 1 to 4, wherein power is supplied to a ferrite core coil unit formed of the overlapping pot-type ferrite cores. 6. The height of the ferrite core coil unit ring from the surface of the support member to the surface of each ferrite core coil unit is substantially constant. A power transmission device according to claim 1. 7. The power transmission device according to claim 1, wherein the support member is formed of a non-magnetic member. 8. A first housing member attached to a hollow shaft or formed integrally with the hollow shaft, and a second housing member rotatably attached to the first housing member by a bearing. The first housing member and the second housing member each include a plurality of ferrite core coil units accommodating a coil in each annular recess of a plurality of pot-type ferrite cores having an annular recess formed therein; A support member that is in contact with the bottom surface of the ferrite core coil unit opposite to the surface on which the annular concave portion is formed, and supports the plurality of ferrite core coil units, wherein the first housing member and the second housing member In each of the support members, the plurality of ferrite core coil units are disposed annularly at substantially equal intervals, The ferrite core coil unit rings of the first housing member and the second housing member are formed to have substantially the same diameter, and the ferrite core coil unit rings of the first housing member and the second housing member are coaxial. A rotary joint, wherein the rotary joint is disposed so as to have a predetermined gap therebetween and is rotatable relative to each other. 9. An antenna member having a pattern formed on a substrate having a diameter larger than the outer diameter of the hollow shaft is provided on each of the first housing member and the second housing member. 9. The rotary joint according to claim 8, wherein the ferrite core coil unit ring has a diameter different from an outer diameter of the substrate, and is arranged to face each other with a predetermined gap.