JP2001085149A - Induction heating roller device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause thermal crowns generated on a roller to become symmetrical with respect to the center of the shell width of the roller by causing the center of a magnetism distribution curve generated by an induction coil to coincide with the center of the shell width of the roller. SOLUTION: An induction heating mechanism 4 is provided inside a rotating roller 1. An induction coil 6 in the induction heating mechanism comprises a pair of coil portions 6A, 6B opposing each other via a space 15 along the axis thereof. Each coil portion comprises a wire wound into even-numbered layers, with the wires of the layers connected in series with one another. Both ends of the wire connected in series are drawn into the space. An excitation power supply is connected between both ends drawn into the space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotating induction heating roller device.

[0002]

2. Description of the Related Art As is well known, an induction heating roller device is provided with an induction heating mechanism including an iron core and an induction coil wound around the inside of a rotating roller. This structure will be described with reference to FIG. 7 showing a conventional example. Reference numeral 1 denotes a roller, and 2 denotes a drive shaft integrally mounted on both sides thereof, which is rotatably supported by a machine base via a bearing (not shown). It is rotationally driven by an arbitrary drive source.

[0003] Reference numeral 3 denotes a plurality of jacket chambers provided inside the peripheral wall of the roller 1 and provided along the circumferential direction of the roller 1, for example, by being drilled along the axial direction of the roller 1 by a drill. Is formed. Each of the jacket chambers 3 is independent of each other, or at least one end thereof is connected to each other by a communication groove. Inside the jacket chamber 3, a gas-liquid two-phase heat medium is sealed, and the temperature distribution on the peripheral wall surface of the roller 1 is made uniform by the gas-liquid phase conversion of the heat medium.

[0004] Reference numeral 4 denotes an induction heating mechanism, which comprises a cylindrical iron core 5 and an induction coil 6 wound therearound. Both sides of the induction heating mechanism 4 are supported inside the roller 1 by support rods 7. The support rod 7 is inserted into the drive shaft 2 and is supported by the drive shaft 2 via a bearing 8. The induction coil 6 passes through a through-hole 9 provided in the iron core 5 via a lead wire, passes through the inside of the support rod 7, is led out to the outside, and is connected to an external AC power supply.

In the induction heating roller device having such a configuration, the body width of the roller 1 (the length of the peripheral wall of the roller 1 along the axial direction of the roller 1) is set in accordance with the width of the object to be heated. It is usually done. If the body width is set to be much longer than the width of the object to be heated, the roller must be made unnecessarily large, and if it is set to a length equal to or less than the width of the object to be heated, The heating element cannot be heated sufficiently.

The induction heating mechanism 4 arranged inside the roller having the set body width is also inside the roller, and needs to be manufactured to have a sufficient length along the axial direction thereof. is there. If this is made short, the peripheral wall of the roller will not be able to generate sufficient heat over its entire length.

In such an induction heating mechanism, the induction coil 6 used for the induction heating mechanism is generally formed by winding an electric wire in two or more layers, and the electric wires in each layer are connected in series. is there. Then, both ends of the series circuit, that is, a winding start portion 10 which is one end thereof, and a winding end portion 11 which is the other end thereof pass through the through-hole 9 provided in the iron core 5 to the outside as described above. It is withdrawn.

Conventionally, as shown in FIG. 7, a space 13 is provided between one end face of the induction coil 6 and the flange 12 of the bobbin.
A through hole 9 is formed in the iron core 5. For this reason, this space 13 has become a dead space. That is, the iron core 5 can be installed symmetrically about the center along the body width of the roller 1,
Since the space 13 must be provided on one end face side of the induction coil 6, the center of the induction coil 6 along the axial direction is located along the axial direction on the opposite side of the space 13 from the center of the roller. It becomes biased.

Referring to FIG. 8, if M is a straight line passing through the center of the roller in the figure, a straight line N passing through the center of the induction coil 6 is located at a position deviated from the straight line M. . On the other hand, the magnetic distribution curve due to the induction coil has a maximum value at the center of the induction coil and becomes lower as going to both sides thereof. The heat distribution of the roller by the induction coil coincides with the magnetic distribution curve. B indicates a distribution curve of the surface temperature of the roller. It is almost flat. This is due to the action of the heating medium in the jacket chamber.

If the center of the magnetic distribution curve is displaced with respect to the center of the roller as described above, heat cannot be effectively generated across both ends of the roller, so that the following problem occurs. I do. That is, even though the surface temperature distribution of the roller becomes uniform due to the action of the heat medium in the jacket chamber 3, the roller generates heat in accordance with the magnetic distribution curve on the inner surface. The center of the crown will not coincide with the center of the roller. In other words, even though the surface temperature distribution of the roller is apparently symmetric about the center of the roller, the thermal crown is no longer symmetric.

In a case where a roller to be heated such as a sheet is rolled together with a roller in such a state, for example, a nip roller, if the thermal crown is deviated from the center of the roller, the shaft centers of both rollers are rotated as the roller is rotated. Crosses, and the object to be heated meanders. When such a meandering motion occurs, the rolling is not performed smoothly, which adversely affects the quality. Further, the object to be heated cannot be uniformly rolled over its entire width, which also adversely affects the quality of the object to be heated.

[0012]

SUMMARY OF THE INVENTION According to the present invention, when an electric wire constituting an induction coil is drawn out from an iron core, the center of the induction coil and the center of the body width of the roller are easily matched with each other. It is an object of the present invention to match the center of the magnetic distribution curve with the center of the body width of the roller so that the thermal crown generated on the roller is symmetric about the center of the body width of the roller.

[0013]

According to the present invention, there is provided a structure in which an induction heating mechanism including an iron core and an induction coil wound around the iron core is provided inside a rotating roller. Along with a pair of coil parts facing each other via a space, each coil part has an even number of windings of the electric wire, and connects the electric wires of each layer in series, between both ends of the electric wires connected in series. And an excitation power supply.

The space used for drawing out the electric wire is
Since they are in the center of both coil parts, they can be arranged symmetrically with respect to the center of the roller. Therefore, the magnetic distribution curves of both coil portions are symmetric with respect to the center of the roller. Thereby, the thermal crown generated in the roller can be made symmetrical with respect to the center of the roller.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. 7 and 8 indicate the same or corresponding parts. As shown in FIG. 1, the induction coil is constituted by a pair of identically shaped coil portions 6A and 6B facing each other via a space 15 along the axial direction of the induction coil.

Each of the coil sections is, for example, as shown in FIG.
It is wound with even or more layers. The electric wires of each layer in each coil portion are connected in series by connecting one end to each other on the surface opposite to the facing surface. The other end of the electric wire of each layer is led out through a through hole 16 provided in the iron core 5 so as to open in the space 15.

1, 3, and 4, the winding start portion 22 of the lower coil wire 21 constituting the coil portion 6A and the winding start portion 24 of the upper coil wire 23 of the coil portion 6B have the same penetration. It is led out through the hole 16 and is connected together there. Reference numeral 25 denotes the connection portion. The winding end of the lower coil wire 21 of the coil portion 6A and the winding end of the upper coil wire 26 are connected by a conducting wire 27. The winding end of the upper coil electric wire 23 of the coil portion 6B and the winding end of the lower coil electric wire 28 are connected by a conducting wire 29.

As a result, all the coil wires 21, 26, 23, 28 are connected in series between the lead wires 30, 31. The lead wires 30 and 31 are led out through the inside of the support rod 7 and are connected to an excitation power supply (AC power supply) as appropriate. In this configuration, the excitation power supply is connected to both ends of the series circuit of the coil wires in one coil unit via the series circuit of the coil wires in the other coil unit.

If the coil portions 6A and 6B are formed in the same shape, the two coil portions 6A and 6B are located symmetrically with respect to the spacer 15 and thus with respect to the central portion along the axial direction of the induction coil 6. Will be placed. The induction heating mechanism 4 configured as described above is disposed at the center of the inside of the roller 1 (therefore, the center of the body width of the roller). In this way, the straight line N passing through the center of the magnetic distribution curve A by the induction coil 4 can be matched with the center of the roller 1 as shown in FIG.

As a result, the roller 1 generates heat evenly over the entire body width, and the thermal crown of the heat-generating roller 1 is generated symmetrically about the center of the roller 1. Therefore, even when used together with the nip roller, the meandering or uneven rolling of the object to be heated can be prevented beforehand.

In the configuration shown in FIG. 3, all the coil electric wires are connected in series, but the present invention is not limited to this.
As shown in FIG. 5, one coil portion 6A and the other coil portion 6B may be connected in parallel (in this case, the collective connection portion 25 is provided at two places), or as shown in FIG. As described above, the coil portions 6A and 6B may be pulled out independently of each other.

In any case, the coil wires of the coil portions 6A and 6B are connected in series at the end portions of the windings so as to be connected in series. An excitation power supply is connected between both ends of the serially connected coil wires. In the drawing, both ends of the serially connected coil wires are drawn out through the through holes 16, but the through holes 16 are not necessarily required, and for example, the ends of the coil wires may be connected in the space 15. Alternatively, it may be drawn out from the space 15 to the outside.

Further, in each of the figures, the induction coil 6 is divided into two parts to form the coil portions 6A and 6B. However, the present invention is not limited to this.
The respective induction coils may be configured to be divided into two pairs, and each of the induction coils may be configured as shown in the figure.

[0024]

As described above, according to the present invention, the center of the roller along the width of the roller coincides with the center of the magnetic distribution curve by the induction heating mechanism installed inside the roller. There is an effect that the thermal crown generated in the roller can be made symmetrical about the center of the roller.

[Brief description of the drawings]

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

FIG. 2 is an operation explanatory diagram of FIG. 1;

FIG. 3 is a connection diagram of the induction coil of FIG. 1;

FIG. 4 is a plan view of the induction heating mechanism of FIG. 1;

FIG. 5 is a connection diagram of another induction coil according to the present invention.

FIG. 6 is a connection diagram of still another induction coil according to the present invention.

FIG. 7 is a sectional view showing a conventional example.

FIG. 8 is an operation explanatory diagram of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Roller 4 Induction heating mechanism 5 Iron core 6 Induction coil 6A Coil part 6B Coil part 15 Space 16 Through hole A Magnetic distribution curve

Claims (1)

[Claims] 1. An induction heating roller device provided with an induction heating mechanism including an iron core and an induction coil wound around the iron core inside a rotating roller, wherein the induction coil comprises:
It is constituted by coil portions that are paired facing each other via a space along the axial direction, and each of the coil portions is formed by winding an electric wire in an even number layer, connecting the electric wires of each layer in series, and being connected in series. An induction heating roller device in which an exciting power supply is connected between both ends of a wire.