JP2552367Y2 - Crown control roll - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crown control roll having a locally variable roll crown such as a nip roll used in various forms in the papermaking process.

[0002]

2. Description of the Related Art Heretofore, as a crown control roll of this kind, a Japanese Patent Application No. Hei 1-333729 previously filed by the present applicant has been used.
No. 2 (Japanese Patent Application Laid-Open No. 3-199482).

[0003] The crown control roll of the above-mentioned application is provided with a plurality of electromagnet bodies having an electromagnetic attraction portion having a coil wire wound on one side in the circumferential direction on an outer periphery of a fixed shaft, fixed along the axial direction of the fixed shaft. An outer cylinder made of a magnetic material that surrounds the outer periphery of the electromagnet body with a required gap is rotatably supported on the outer periphery of the fixed shaft via a bearing. By energizing the wound coil wire, the outer cylinder is partially attracted and deformed by the electromagnetic attraction unit, and the attraction force of the electromagnetic attraction unit of each electromagnet is adjusted to freely adjust the axial shape of the outer cylinder. So that it can be changed.

[0004]

However, in the crown control roll as described above, since the outer cylinder is deformed by using only the attraction force of the electromagnet, a large amount of electric power is required, and the amount of generated heat is very large. Also, the size of a cooling device such as a blower for supplying a cooling medium such as air into the outer cylinder must be increased, which has a problem in terms of installation and cost.

In view of the above circumstances, the present invention can generate a required suction force with a minimum amount of electric power to enable stable shape control, suppress the amount of heat generation, and reduce the size of the cooling device. Another object of the present invention is to provide a crown control roll that is advantageous in terms of cost and the like.

[0006]

According to the present invention, a plurality of electromagnets having an electromagnetic attraction portion having a coil wire wound around one side in the circumferential direction are fixedly provided on the outer periphery of the fixed shaft along the axial direction of the fixed shaft. And a crown control roll in which an outer cylinder made of a magnetic material surrounding the outer periphery of the electromagnet body with a required gap is rotatably supported on the outer periphery of the fixed shaft via a bearing. A permanent magnet is attached between the base ends of the portions.

[0007]

Therefore, the electromagnetic attraction portion of the electromagnet body is already magnetized by the permanent magnet. In this state, the coil wire wound around the electromagnetic attraction portion of the electromagnet body is energized in a direction to increase the magnetic field by the permanent magnet. When this is done, the outer cylinder is partially attracted and deformed by the electromagnetic attraction part with a strong force, so that by adjusting the attraction force of the electromagnetic attraction part of each electromagnet, the axial shape of the outer cylinder changes arbitrarily.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention.
In the figure, reference numeral 1 denotes a crown control roll, which presses a wet paper 3 or the like between itself and a press roll 2 which is provided so as to be able to move up and down.

The crown control roll 1 has a fixed shaft 5 whose both ends are supported by a spherical bush 4 and both ends of which are formed by bearings 7 near the both ends of the fixed shaft 5 so as to form an annular space 6 on the outer periphery of the fixed shaft 5. And an outer cylinder 8 made of a magnetic material rotatably supported on the outer cylinder 8.

On the outer periphery of the fixed shaft 5 in the annular space 6, a silicon circular tube 9 having a cylindrical shape and having a required length is fixed continuously in the axial direction. 9
A plurality of electromagnet bodies 11 made of a magnetic material having a cylindrical shape and having an electromagnetic attraction portion 10 at the lower part of the outer circumference are continuously fixed in the axial direction.

As shown in FIG. 2, the electromagnet body 11 is formed so that an electromagnetic attraction part 10 in which a coil wire 12 is wound around a plurality of protruding iron cores 12 ′ in the lower half is symmetrical. The outer periphery of the electromagnetic attraction unit 10 is formed so as to maintain a required gap G (for example, about 0.5 to 1.0 mm) between the outer periphery of the electromagnetic attraction unit 10 and the inner periphery of the outer cylinder 8. Although not shown, an insulator is interposed between the iron core 12 'and the coil wire 12.

Further, an iron core 12 'of each electromagnetic attraction unit 10 is provided.
Permanent magnets 18 are attached between the base ends, and the iron cores 12 'are magnetized by the permanent magnets 18, respectively, as shown in FIG.
N magnetic poles are generated.

As shown in FIG. 1, the electromagnet body 11 has a gap sensor 19 for detecting a gap G between the outer periphery of the electromagnetic attraction unit 10 and the inner peripheral surface of the outer cylinder 8 in the axial direction of the crown control roll. They are arranged at required intervals.

Each coil wire 12 wound around each electromagnetic attraction portion 10 of each of the electromagnets 11 passes through the inside of the fixed shaft 5 and is led out from one end thereof.

As shown in FIG. 3, each of the coil wires 12 has its own amplifier 1 for each one guided to each of the electromagnet bodies 11.
3 is connected to a control device 15 having a DC power supply device 14.

The control device 15 receives a measurement signal 17 from a measuring device 16 which moves in the width direction of the wet paper web 3 and measures the water content or thickness in the width direction downstream of the crown control roll 1. And the gap sensors 19
Is input.

In addition, a cooling medium such as air is supplied from a cooling device such as a blower (not shown) into the outer cylinder 8 so as to suppress a temperature rise due to heat generation of the coil wire 12.

Next, the operation of the above embodiment will be described.

In the electromagnetic attraction section 10 of each electromagnet body 11, each iron core 12 'is magnetized by a permanent magnet 18, respectively.
As shown in FIG. 2, S and N magnetic poles are generated, and a control device 15 applies a current from a power supply device 14 to a coil wire 12 of an electromagnetic attraction unit 10 provided below a desired electromagnet body 11. When guided through the amplifier 13, a magnetic force is generated in each electromagnetic attraction unit 10 by the current.

At this time, if a current is applied to the coil wire 12 so that a magnetic field is generated in the same direction as the direction of the magnetic field generated in each electromagnetic attraction unit 10 by the permanent magnet 18, a small amount of power and a small amount of heat can be suppressed. While the same magnetic force as before can be obtained,
If an electric current is applied in the opposite direction, the magnetic field generated by the permanent magnet 18 is canceled and the magnetic force can be eliminated.

When an electric current is applied to the coil wire 12 in a direction to increase the magnetic field generated by the permanent magnet 18, the outer cylinder 8 close to the electromagnetic attraction unit 10 is strongly magnetized and electromagnetically attracted as shown by an arrow in FIG. It is attracted to the electromagnetic attraction unit 10 by the force X, and the sum of the electromagnetic attraction force X of each electromagnetic attraction unit 10 acts as a pressing force F for pushing the outer cylinder 8 upward.

The magnitude of the pressing force F can be arbitrarily adjusted by changing the current or voltage value of the power source guided to the electromagnet 11.

Therefore, as shown in FIG. 3, a measurement signal 17 from a measuring device 16 for detecting the moisture or thickness of the wet paper web 3 in the width direction, the outer periphery of the electromagnetic suction unit 10 and the inner periphery of the outer cylinder 8 are provided. A detection signal 20 from a gap sensor 19 for detecting a gap G with a surface is input to the control device 15, and a current or a voltage value guided to each of the electromagnets 11 is determined based on the measured value and the detected value. By changing and adjusting the pressing force F ₁ , F ₂ , F at a required position in the axial direction of the crown control roll 1.
_3, to allow zone control bending by adjusting the · · · F _n arbitrarily, thus controlling moisture or thickness of the wet paper by controlling a constant nip pressure between the press roll 2 in the width direction in the width direction constant can do.

In the above embodiment, the case where the electromagnetic attraction unit 10 of the electromagnet body 11 is located on the lower side has been described, but some of the electromagnetic attraction unit 10 are located at the lower side, and some of the electromagnetic attraction units 10 are located at the upper side. When the fixation of the electromagnet body 11 to the fixed shaft 5 is changed so as to satisfy the following condition, the pressing force F acts on a part of the outer cylinder 8 and the opposite pulling force acts on the other parts. The bending deformation (zone control) of the outer cylinder 8 can be performed more accurately.

In this way, it is possible to generate the required suction force with the minimum power and perform stable shape control.
In addition, the amount of heat generation can be suppressed to reduce the size of the cooling device, which is advantageous in terms of installation and cost.

It should be noted that the crown control roll of the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[0028]

As described above, according to the crown control roll of the present invention, it is possible to generate a required suction force with a minimum amount of electric power, perform stable shape control, and suppress the amount of heat generated. As a result, the cooling device can be downsized, and an excellent effect can be achieved that is advantageous in terms of installation, cost, and the like.

[Brief description of the drawings]

FIG. 1 is a cutaway front view of one embodiment of the present invention.

FIG. 2 is a cross-sectional view in the II direction of the crown control roll shown in FIG.

FIG. 3 is a block diagram showing an example of a control system of the crown control roll shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crown control roll 5 Fixed shaft 7 Bearing 8 Outer cylinder 10 Electromagnetic attraction unit 11 Electromagnet body 12 Coil wire 18 Permanent magnet

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of electromagnets each having an electromagnetic attraction portion having a coil wire wound on one side in the circumferential direction on an outer periphery of a fixed shaft, and a plurality of electromagnets are fixed along an axial direction of the fixed shaft. In a crown control roll in which an outer cylinder made of a magnetic material that surrounds with a required gap is rotatably supported on the outer periphery of the fixed shaft via a bearing, a permanent control is provided between the base ends of the electromagnetic attraction portions. A crown control roll having a magnet mounted thereon.