JP5508745B2 - Induction heating roll - Google Patents

Description

  The present invention relates to a high frequency electromagnetic induction heating roll.

  Heating rolls used in calendar machines, embossing machines, laminator machines, etc. are generally low-frequency induction heating systems using commercial wave numbers (50 Hz, 60 Hz), electrical resistance heating systems, heating medium circulation systems, and steam heating systems. well known. Of these, the low frequency induction heating method is preferred because it is easy to use and has good temperature characteristics (for example, Patent Document 1), but there is a problem that the device price is high, the number of manufacturers is limited, and it is not so wide. The fact is that it is not used.

  Further, in the conventional low frequency induction heating method, since the induction coil is installed inside the roll body, it is difficult to reduce the outer diameter of the roll and it is difficult to cool the induction coil. In order to improve this problem, a proposal has been made in which a high-frequency coil is disposed outside the roll body, a high-frequency magnetic flux is applied to the roll body from the outside, and the roll body is heated (Patent Document 2).

  Further, when the length of the roll body in the longitudinal direction is long, a temperature difference is likely to occur between the center portion and both ends of the roll body surface. If temperature irregularity occurs on the surface of the roll main body, the processed product (paper, film, etc.) that contacts the outer peripheral surface of the roll main body cannot be sufficiently heated, causing variations in quality of the processed product. In order to improve this problem, as shown in FIG. 13, a proposal has been made to equalize the temperature distribution in the longitudinal direction of the roll body surface by embedding a plurality of heat pipes 101 near the outer surface of the roll body 100. (Patent Document 3).

JP 2003-36964 A Japanese Patent Publication No. 1-18853 JP 2004-292860 A

  However, the proposal described in Patent Document 2 has a problem that the high-frequency coil is easily overheated by radiant heat from the roll body, and a problem that the surface temperature in the longitudinal direction of the roll body cannot be kept constant.

  Further, in the proposal described in Patent Document 3, in order to embed the heat pipe 101 in the roll body 100 as shown in FIG. 13, for example, a deep hole is formed in the roll body 100 using a processing technique called BTA (Boring and Trepanning Association) processing. It is necessary to provide. This processing has a problem that a special tool is required and costs are high.

  In order to solve the above-mentioned conventional problems, the present invention can prevent the high-frequency coil from being overheated by radiant heat from the roll body, and can easily generate temperature unevenness in the longitudinal direction of the roll body surface at low cost. An induction heating roll that can be suppressed is provided.

The induction heating roll of the present invention has a roll body having at least an outer shell portion formed of a metal layer,
An induction heating device that is disposed outside the roll body and induction-heats the roll body using a high frequency coil comprising a magnetic core and a coil wire that winds the magnetic core,
The metal layer is an induction heating roll disposed at a position where the magnetic flux is hardened,
The induction heating device includes a magnetic core made of ferrite core having an E-shaped cross section, and the high-frequency coil and a coil wire winding the magnetic core, a cooling means for flowing cooling air around the high-frequency coil, the cooling The means supplies cooling air into the induction heating device, and the cooling air passes through the front surface of the high frequency coil and is discharged out of the induction heating device to prevent overheating of the high frequency coil due to radiant heat from the roll body. Structure,
The roll body includes an outer cylinder that forms the outer shell portion, and an inner cylinder that is coaxially disposed in the outer cylinder and forms the sealed space between the outer cylinder and the outer cylinder. It is a jacket structure, a heat medium is enclosed in the sealed space, and the internal volume of the sealed space is PV ≦ 0.04 (where PV is pressure (atm) × volume (m ³ )) Is set to be ,
At one end of the roll body, an opening communicating with the internal space of the inner cylinder is formed, and the roll body includes means for flowing a cooling fluid from the opening to the inside of the inner cylinder. The temperature of the roll body can be controlled and overheating can be prevented .

  According to the induction heating roll of the present invention, a roll main body having at least an outer shell portion formed of a metal layer, and a high-frequency coil that is disposed outside the roll main body and includes a magnetic core and a coil wire that winds the magnetic core is used. An induction heating device for inductively heating the roll body, wherein the metal layer is disposed at a position where the magnetic flux is constrained, a sealed space is formed inside the roll body, and the sealed space By enclosing the heat medium therein, it is possible to realize an induction heating roll that can easily suppress the occurrence of temperature unevenness in the longitudinal direction of the roll body surface at low cost. Moreover, since the said induction heating apparatus has the cooling device for cooling the said high frequency coil, it can prevent the overheating of the high frequency coil by the radiant heat from a roll main body.

It is a figure which shows an example of the induction heating roll of this invention. 1A is a front view and FIG. 1B is a left side view. It is a figure which shows an example of the induction heating apparatus in the induction heating roll of this invention. 2A is a plan view, FIG. 2B is a front view, and FIG. 2C is a right side view. It is II sectional drawing in FIG. 2B. It is II-II expanded sectional drawing in FIG. 2A. It is sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected along a longitudinal direction. It is other sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected along the longitudinal direction. It is a figure which shows the other example of the induction heating roll of this invention. 7A is a front view and FIG. 7B is a left side view. It is sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected in the direction orthogonal to a longitudinal direction. It is another sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected in the direction orthogonal to a longitudinal direction. It is another sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected in the direction orthogonal to a longitudinal direction. It is another sectional drawing when the roll main body in the induction heating roll of this invention is cut | disconnected in the direction orthogonal to a longitudinal direction. It is a partially expanded front view which shows an example of the external appearance of the inner cylinder provided in the inside of the roll main body in the induction heating roll of this invention. It is a partially cutaway front view of the conventional roll main body.

  The induction heating roll of the present invention uses a high-frequency coil comprising a roll main body having at least an outer shell portion made of a metal layer, a magnetic core and a coil wire wound around the magnetic core, arranged on the outside of the roll main body. An induction heating device for inductively heating the roll body, wherein the metal layer is an induction heating roll disposed at a position where the magnetic flux is blocked, and the induction heating device has a cooling device for cooling the high-frequency coil. A sealed space is formed inside the roll body, and a heat medium is sealed in the sealed space.

  An induction heating roll that can easily suppress the occurrence of temperature unevenness in the longitudinal direction of the roll body surface at low cost by providing a sealed space inside the roll body and enclosing a heat medium in the space. realizable. In addition, since the induction heating device includes a cooling device that cools the high-frequency coil, overheating of the high-frequency coil due to radiant heat from the roll body can be prevented.

  The roll body includes an outer cylinder that forms the outer shell, and an inner cylinder that is coaxially disposed in the outer cylinder and forms the sealed space with the outer cylinder. It is preferable to have a jacket structure. Thereby, the efficiency of the heat transfer by a heat medium can be improved and the suppression effect of the temperature nonuniformity generation | occurrence | production in the longitudinal direction of the roll main body surface can be improved.

  An opening that communicates with the internal space of the inner cylinder is formed at one end of the roll body, and the roll body preferably includes means for flowing a cooling fluid from the opening to the inside of the inner cylinder. . Thereby, temperature control of roll main body itself is possible and it can prevent that a roll main body overheats.

  As the cooling device of the induction heating device, a device that allows cooling air to flow around the high-frequency coil can be used, and is realized by, for example, a cooling air pipe.

  It is preferable to arrange a plurality of induction heating devices having different lengths in the longitudinal direction of the roll body. Thereby, generation | occurrence | production of the temperature nonuniformity in the longitudinal direction of a roll main body can be suppressed.

  Asperities are preferably formed on the outer peripheral surface of the inner cylinder. Thereby, the heat transfer efficiency by a heat medium can be raised more. When the irregularities are spiral and formed so that the spiral direction is reversed with respect to the central portion in the longitudinal direction of the inner cylinder, heat is transferred from the central portion of the roll body to both ends. Therefore, the effect of suppressing the occurrence of temperature unevenness in the longitudinal direction of the roll body surface can be further enhanced.

  Embodiments of the present invention will be specifically described below with reference to the drawings. Note that the present invention is not limited to this.

(Embodiment 1)
In Embodiment 1, an example of the induction heating roll of the present invention will be described. 1A and 1B are views showing an example of the induction heating roll of the present invention, FIG. 1A is a front view, and FIG. 1B is a left side view. For convenience of explanation, FIG. 1 shows only the roll body and the induction heating device.

  As shown in FIG. 1, the induction heating roll 1 of the first embodiment includes a roll body 3 and an induction heating device 2 disposed outside the roll body 3. Since this induction heating roll 1 is a system in which the roll body 3 is heated from the outside, a space for storing the high-frequency coil in the roll body 3 is not required, and the diameter of the roll body 3 can be reduced to 30 mm. On the other hand, even when the diameter of the roll main body 3 is set to 1500 mm or more, it is not necessary to provide a large-diameter coil inside the roll main body 3, so that the cost can be reduced as compared with the conventional low-frequency heating method.

  The roll body 3 has at least an outer shell portion formed of a metal layer, and the metal layer is disposed at a position where the magnetic flux is prevented. As the metal layer, a ferromagnetic material, stainless steel (SUS), or the like can be used.

  The induction heating device 2 induction-heats the roll body 3 using a high-frequency coil composed of a magnetic core and a coil wire that winds the magnetic core. The induction heating device 2 is arranged so that the longitudinal direction of the induction heating device 2 and the longitudinal direction of the roll body 3 are substantially parallel. Here, the length of the induction heating device 2 is the roll body 3. It was longer than the length in the longitudinal direction. Thereby, since the roll main body 3 can be heated substantially uniformly from one end to the other end, the occurrence of temperature unevenness in the longitudinal direction of the surface of the roll main body 3 can be suppressed. Furthermore, the induction heating device 2 has a cooling device for cooling the high-frequency coil. Thereby, it can prevent that a high frequency coil overheats.

  Next, the structural example of the induction heating apparatus 2 shown in FIG. 1 is demonstrated using FIGS. 2A to 2C are diagrams showing an example of the induction heating device in the induction heating roll of the present invention. 2A is a plan view, FIG. 2B is a front view, and FIG. 2C is a right side view. 3 is a cross-sectional view taken along the line II in FIG. 2B, and FIG. 4 is an enlarged cross-sectional view taken along the line II-II in FIG. 2A.

  As shown in FIGS. 2 to 4, the induction heating device 2 of FIG. 1 includes a high-frequency coil 20 and a cooling air pipe 30 as a cooling device inside, for example, a high-frequency power source installed outside. When a high frequency is supplied to the high frequency coil 20 from the power supply lead wire 40 (not shown), the metal layer of the outer shell portion of the roll body 3 of FIG.

  As shown in FIG. 4, the high-frequency coil 20 includes a magnetic core 21 made of a ferrite core having an E-shaped cross section, and a coil wire 22 around which the magnetic core 21 is wound. A glass mat 26 is provided on the lower surface of the high-frequency coil 20, that is, the surface facing the bottom plate 16 of the induction heating device. An electrically insulating resin layer 24 is molded on the surface including the lower surface of the high-frequency coil 20. In addition, an electrical insulating resin 23 is also molded in the concave portion of the magnetic core 21. The electrical insulating resin layer 24 is provided with a sensor hole 25 into which a thermal sensor for measuring temperature can be inserted.

  As shown in FIGS. 2 and 3, the shape of the induction heating device 2 in FIG. 1 is a substantially rectangular parallelepiped. Here, the induction heating device 2 has a length of 101 mm, a width of 685 mm, and a height of 55.5 mm. As for the material and size of each plate, the front plate 13 and the back plate 15 were made of aluminum and had a length of 55 mm, a width of 680 mm, and a thickness of 5.0 mm. The left and right plates 12 and 14 were “Rossna boards” manufactured by Nikko Kasei Co., Ltd., and had a length of 55.5 mm, a width of 101 mm, and a thickness of 2.5 mm. The top plate 10 is made of aluminum and has a length of 101 mm, a width of 15 mm, and a thickness of 2.5 mm. The bottom plate 16 was “Rossna Board” manufactured by Nikko Kasei Co., Ltd., and had a length of 96 mm, a width of 680 mm, and a thickness of 1.0 mm. Note that the shape of the induction heating device 2 and the material and size of each plate constituting the induction heating device 2 are not limited to these.

  As shown in FIG. 2C, the shape of the high-frequency coil 20 is a substantially rectangular parallelepiped whose lower ends are tapered in the longitudinal direction. Here, the high-frequency coil 20 has a length of 71 mm, a width of 630 mm, and a height of 48 mm. The high frequency coil 20 is fixed to the five top plates 10 using the screw members 11 so as not to contact the front plate 13, the back plate 15, the left and right side plates 12, 14 and the bottom plate 16 of the induction heating device. At this time, the distance between the front plate 13 and the back plate 15 was 20 mm, the distance between the left and right side plates 12 and 14 was 25 mm, and the distance between the bottom plate 16 was 3 mm. The shape and size of the high frequency coil 20 are not limited to these.

  As shown in FIGS. 2 and 3, the cooling air pipe 30 is inserted below the top plate 10 of the induction heating device and along the longitudinal direction of the high-frequency coil 20, and passes through the induction heating device. One end is fixed to the left side plate 12 by a screw member 31. The cooling air pipe 30 has, for example, a cylindrical shape having an outer diameter of 10 to 12 mm and an inner diameter of 8 to 10 mm, and has a plurality of holes 30a (see FIG. 4) for discharging cooling air at the lower part in the longitudinal direction. The cooling air discharged from the plurality of holes 30a flows in the arrow direction 32 to cool the high-frequency coil 20 and prevent the high-frequency coil 20 from being overheated by radiant heat from the roll body. Here, the cooling air pipe 30 has a diameter of 12 mm outer diameter and 10 mm inner diameter, but is not limited thereto. However, in order to efficiently flow the cooling air around the high frequency coil 20, the cooling air pipe 30 is sized to contact both the high frequency coil 20 and the front plate 13, as shown in FIG. Is preferred.

  Next, the internal structure of the roll body 3 of FIG. 1 will be described with reference to FIG. FIG. 5 is a cross-sectional view when the roll body in the induction heating roll of the present invention is cut along the longitudinal direction.

As shown in FIG. 5, the roll body 3 of Embodiment 1 has a sealed space 51 formed therein. Here, the sealed space 51 has a cylindrical shape. That is, the body portion of the roll body 3 is a cylindrical body whose both ends are closed (hereinafter referred to as the outer shell portion 50). The internal volume of the sealed space 51 was set to satisfy PV ≦ 0.04. Here, PV means “pressure (atm) × volume (m ³ )”.

  A heat medium is enclosed in the sealed space 51. As the heat medium, water, water vapor, oils and the like can be used. Since this heat medium circulates in the sealed space 51, heat is transmitted substantially uniformly from the inside of the roll body 3 to the entire outer surface, and the outer shell portion 50 of the roll body 3 is held substantially uniformly at a predetermined temperature. Will be. Thereby, generation | occurrence | production of the temperature nonuniformity in the longitudinal direction of the roll main body 3 surface can be easily suppressed at low cost, without using a conventional heat pipe.

  Next, the separation distance between the induction heating device 2 and the roll body 3 in FIG. 1 will be described.

In order to optimize the separation distance between the induction heating device 2 and the roll body 3, a heating test using the induction heating device and iron plate (length 100 mm, width 745 mm, thickness 15 mm) shown in FIGS. Went. Specifically, first, a high frequency power is supplied to the high frequency coil 20 in the induction heating apparatus 2 from a 5 kW high frequency power supply via the power supply lead 40. Then, a high frequency magnetic field is generated from the high frequency coil 20 by applying a high frequency voltage, and the iron plate is induction-heated. Input current value at this time, capacitance, and an output display, but such changing the distance between the induction heating device 2 and the steel plate in the range of 9mm~15.0mm were et measured boss. Table 1 shows the measurement results.

  As shown in Table 1, when the separation distance exceeded 11 mm, the input current, the capacity, and the output display decreased. From this result, it is understood that the separation distance is preferably within 11 mm. On the other hand, if the separation distance is 9 mm or less, not only the magnetic coupling cannot be taken, but also the high frequency coil in the induction heating device is overheated and deteriorated by the radiant heat from the roll body, which is not preferable. Therefore, the separation distance between the induction heating device 2 and the roll body 3 in FIG. 1 is preferably 9 to 11 mm.

  According to the induction heating roll of the first embodiment as described above, the induction heating device 2 is arranged outside the roll body 3, and the roll body 3 is induction-heated from the outside and sealed inside the roll body 3. By forming the space 51 and enclosing the heat medium in the sealed space 51, it is possible to easily suppress the occurrence of temperature unevenness in the longitudinal direction of the roll body 3 at low cost. In addition, by providing the induction heating device 2 with the cooling air pipe 30, it is possible to prevent overheating of the high-frequency coil 20 due to radiant heat from the roll body 3.

(Embodiment 2)
In Embodiment 2, another example of the induction heating roll of the present invention will be described. The induction heating roll of the second embodiment is the same as the induction heating roll of the first embodiment except that the roll body has a jacket structure. Only differences from the first embodiment will be described below.

  FIG. 6 is another cross-sectional view when the roll body in the induction heating roll of the present invention is cut along the longitudinal direction. 6, the same components as those in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 6, the roll body 3 a according to the second embodiment is arranged coaxially in the outer cylinder 50 that forms the outer shell portion, and between the outer cylinder 50 and the outer cylinder 50. It has a jacket structure including an inner cylinder 55 that forms a sealed space 52. A sealed space 52 formed between the inner peripheral surface of the outer cylindrical body 50 and the outer peripheral surface of the inner cylindrical body 55 is a jacket portion. The internal volume of the sealed space 52 was set to satisfy PV ≦ 0.04. The sealed space 52 is filled with a heat medium. In Embodiment 2, since the roll body 3a has a jacket structure, the amount of heat medium used can be reduced, the efficiency of heat transfer by the heat medium can be increased, and the occurrence of temperature unevenness in the longitudinal direction of the surface of the roll body 3a can be suppressed. The effect can be enhanced.

  At one end of the roll body 3a, an opening 54 communicating with the internal space 56 of the inner cylinder 55 is formed, and means for flowing a cooling fluid from the opening 54 to the internal space 56 of the inner cylinder 55 through the roll body 3a ( (Not shown). Thereby, the temperature control of the roll main body 3a is possible, and it is possible to prevent the roll main body 3a from being overheated or to forcibly cool the roll main body 3a.

  On the other hand, on the other end side of the roll body 3a, the convex support part 53 formed at one end of the inner cylinder 55 has a gap in the recess formed at a position facing the support part 53 of the outer cylinder 50. The inner cylinder body 55 and the outer cylinder body 50 are connected by being inserted. As a result, the expansion and contraction in the longitudinal direction of the outer cylinder 50 and the inner cylinder 55 of the roll body 3a during heating and cooling is absorbed, and cracks are generated at the connecting portion between the outer cylinder 50 and the inner cylinder 55 of the roll body 3a. To prevent it.

  According to such an induction heating roll of the second embodiment, the roll body 3 a is coaxially disposed in the outer cylinder 50 and the outer cylinder 50 and is sealed between the outer cylinder 50. Due to the jacket structure including the inner cylindrical body 55 that forms the space 52, and the sealed space 52 is filled with a heat medium, it is possible to easily generate temperature unevenness in the longitudinal direction of the surface of the roll body 3a at low cost. Can be suppressed. Further, an opening 54 communicating with the internal space 56 of the inner cylinder 55 is formed at one end of the roll body 3a, and a cooling fluid is passed through the roll body 3a from the opening 54 to the internal space 56 of the inner cylinder 55. By providing the cooling means, the temperature of the roll body 3a can be controlled, and the roll body 3a can be prevented from overheating. Further, by connecting the inner cylinder 55 and the outer cylinder 50 via a support portion 53 formed at one end of the inner cylinder 55, the outer cylinder 50 and the inner cylinder in the longitudinal direction during heating and cooling. The thermal expansion / contraction of 55 can be absorbed and the generation of cracks can be prevented.

(Embodiment 3)
In Embodiment 3, another example of the induction heating roll of the present invention will be described. The induction heating roll of the third embodiment is the same as the induction heating roll of the first embodiment except that a plurality of induction heating devices are provided. Only differences from the first embodiment will be described below.

  7A and 7B are views showing another example of the induction heating roll of the present invention, FIG. 7A is a front view, and FIG. 7B is a left side view. 7A and 7B, only the roll body and the induction heating device are shown for convenience of explanation. In the figure, the same components as those in FIGS.

  As shown in FIGS. 7A and 7B, the induction heating roll 1a of the third embodiment is a combination of a plurality of induction heating devices 2 and 4 having different lengths, and these are arranged in the longitudinal direction of the roll body 3. It is.

  The induction heating device 2 and the induction heating device 4 both have the structure shown in FIGS. 2 to 4, but the length of the induction heating device 4 in the longitudinal direction is shorter than that of the induction heating device 2. The induction heating device 4 is used as an auxiliary coil. For example, as shown in FIG. 7A, the induction heating device 4 is installed close to the induction heating device 2 at both ends of the roll body 3 and along the longitudinal direction of the roll body 3. Thereby, the fall of the temperature in the both ends of the roll main body 3 surface can be prevented, and the temperature distribution of the longitudinal direction of the roll main body 3 surface can be made substantially uniform. Here, although the case where the induction heating apparatus 2 which has the length substantially the same as the length of the roll main body 3 and the two induction heating apparatuses 4 whose length is shorter than the induction heating apparatus 2 was shown, each induction heating apparatus was shown. The length and the arrangement position are not limited to this, and it is sufficient that the temperature distribution in the longitudinal direction of the surface of the roll body 3 can be made substantially uniform.

  According to the induction heating roll of the third embodiment, a plurality of induction heating devices 2 and 4 having different lengths are combined, and both ends of the roll body 3 are used with the shorter induction heating device 4 serving as an auxiliary coil. By providing in, the generation | occurrence | production of the temperature nonuniformity in the longitudinal direction of the roll main body 3 can be suppressed.

(Embodiment 4)
In Embodiment 4, another example of the induction heating roll of the present invention will be described. The induction heating roll of the fourth embodiment is the same as the induction heating roll of the second embodiment, except that irregularities are formed on the outer peripheral surface of the inner cylinder. Only differences from the second embodiment will be described below.

  The roll body according to the fourth embodiment has a jacket structure as shown in FIG. 6, and the inner cylindrical body 55 has an uneven surface on the outer peripheral surface.

  Below, the uneven | corrugated shape formed in the outer peripheral surface of the inner cylinder 55 is demonstrated using FIGS. 9-12. The uneven shape is not limited to the following. FIGS. 9-11 is an expanded sectional view when the roll main body in the induction heating roll of this invention is cut | disconnected in the direction (width direction) orthogonal to a longitudinal direction. FIG. 12 is a partially enlarged front view showing an example of the appearance of the inner cylinder provided inside the roll body in the induction heating roll of the present invention.

  In the case of FIGS. 9-11, the outer peripheral surface of the inner cylinder 55 is uneven | corrugated in the circumferential direction. In FIG. 9, the concave and convex shape is a repeated continuous shape of a concave portion and a convex portion 55a having a substantially rectangular cross section, in FIG. 10, a repeated continuous shape of a concave portion and a convex portion 55a having a substantially triangular cross section, and in FIG. Is a continuous continuous shape of a substantially triangular concave portion and a convex portion 55a having a substantially trapezoidal cross section. When irregularities are formed on the outer peripheral surface of the inner cylindrical body 55 in this way, the internal volume of the sealed space 52 between the inner peripheral surface of the outer cylindrical body 50 and the outer peripheral surface of the inner cylindrical body 55 decreases. The heat transfer efficiency of the heat medium enclosed in the sealed space 52 is improved, and the effect of suppressing the occurrence of temperature unevenness in the longitudinal direction of the roll body surface can be enhanced.

  On the other hand, in the case of FIG. 12, spiral irregularities are formed on the outer peripheral surface of the inner cylindrical body 55. Also in this case, since the internal volume of the sealed space 52 between the inner peripheral surface of the outer cylindrical body 50 and the outer peripheral surface of the inner cylindrical body 55 is reduced, the heat of the heat medium enclosed in the sealed space 52 is reduced. The transmission efficiency is improved, and the effect of suppressing the occurrence of temperature unevenness in the longitudinal direction of the roll body surface can be enhanced. Further, in FIG. 12, the spiral irregularities are formed so that the spiral direction is reversed with the central portion of the inner cylindrical body 55 as a boundary. Therefore, heat becomes easy to be transmitted from the center side of the roll body to both ends of the roll body, and the effect of suppressing temperature unevenness in the longitudinal direction of the roll body surface can be further enhanced.

  According to the induction heating roll of the fourth embodiment as described above, by forming irregularities on the outer peripheral surface of the inner cylinder 55, the heat transfer efficiency of the heat medium enclosed in the sealed space 52 is increased, and the roll The effect of suppressing the occurrence of temperature unevenness in the longitudinal direction of the main body surface can be enhanced.

  Hereinafter, the roll body of the present invention will be specifically described with reference to examples. Here, as shown in FIG. 6, the roll main body has a jacket structure including an outer cylindrical body 50 and an inner cylindrical body 55. The outer diameter of the outer cylinder 50 of the roll body is 300 mm, the length of the outer cylinder 50 in the longitudinal direction is 1200 mm (the length of the roll body is 1130 mm, the length of the shaft provided at both ends is 35 mm), The thickness of the outer cylinder 50 was 30 mm. The internal volume of the sealed space 52 (hereinafter referred to as a jacket portion) was set to satisfy PV ≦ 0.04. Water vapor was assumed as a heat medium filled in the jacket portion 52.

Example 1
In the present Example 1, as shown in FIG. 9, the unevenness | corrugation was provided in the outer peripheral surface of the inner cylinder 55 of a roll main body in the circumferential direction. The shape of the unevenness was a continuous continuous shape of a concave portion having a substantially rectangular cross section and a convex portion 55a. The number of concave portions and the number of convex portions 55a are the same, and the width W1 of the concave portions and the width W2 of the convex portions 55a are made equal. The maximum distance L2 between the outer peripheral surface of the inner cylinder 55 and the inner peripheral surface of the outer cylinder 50 was 15 mm, and the minimum distance L3 was 5 mm.

When the internal volume V of the jacket portion 52 was determined, it was 0.0081 m ³ . Since the internal volume of the jacket portion 52 is set to satisfy PV ≦ 0.04, the value of P is 0.48 MPa. The saturated steam temperature was found to be 150 ° C. from the value of P and the steam table.

(Example 2)
In Example 2, the outer circumferential surface of the inner cylinder 55 of the roll body was provided with irregularities in the circumferential direction as shown in FIG. The shape of the concavo-convex shape was a continuous continuous shape of a concave portion having a substantially triangular cross section and a convex portion 55a. The number of concave portions and the number of convex portions 55a are the same. The maximum distance L4 between the outer peripheral surface of the inner cylindrical body 55 and the inner peripheral surface of the outer cylindrical body 50 was 15 mm, and the minimum distance L5 was 5 mm.

When the internal volume V of the jacket portion 52 was determined, it was 0.0081 m ³ . Since the internal volume of the jacket portion 52 is set to satisfy PV ≦ 0.04, the value of P is 0.48 MPa. The saturated steam temperature was found to be 150 ° C. from the value of P and the steam table.

(Example 3)
In Example 3, the outer peripheral surface of the inner cylinder 55 of the roll body was provided with irregularities in the circumferential direction as shown in FIG. The shape of the projections and depressions was a continuous continuous shape of a concave portion having a substantially triangular cross section and a convex portion 55a having a substantially trapezoidal cross section. The number of concave portions and the number of convex portions 55a are the same. The maximum distance L6 between the outer peripheral surface of the inner cylinder 55 and the inner peripheral surface of the outer cylinder 50 was 15 mm, and the minimum distance L7 was 5 mm. The shape of the recess was a triangular prism with a bottom having a triangle with a height of 10 mm and a base W3 of 10 mm, the height of the triangular prism was 1130 mm, and the number of triangular prisms was 16.

When the internal volume V of the jacket portion 52 was determined, it was 0.005 m ³ . Since the internal volume of the jacket portion 52 is set to satisfy PV ≦ 0.04, the value of P is 0.79 MPa. The saturated steam temperature was found to be 170 ° C. from the value of P and the steam table.

(Example 4)
In Example 4, spiral irregularities were provided on the outer peripheral surface of the inner cylinder 55 of the roll body as shown in FIG. The spiral irregularities were formed so that the spiral direction was reversed with the central portion of the inner cylindrical body 55 as a boundary. The maximum distance between the outer peripheral surface of the inner cylinder 55 and the inner peripheral surface of the outer cylinder (not shown) was 15 mm, and the minimum distance was 5 mm. The shape of the concave portion was a triangular prism whose bottom surface was a triangle having a height L8 of 10 mm and a base L9 of 10 mm, the height of the triangular prism was 0.22π mm, and the number of triangular prisms was 60.

When the internal volume V of the jacket portion 52 was determined, it was 0.006 m ³ . Since the internal volume of the jacket portion 52 is set to satisfy PV ≦ 0.04, the value of P is 0.65 MPa. The saturated steam temperature obtained from the value of P and the steam table was 162 ° C.

(Comparative Example 1)
The roll body of Comparative Example 1 has a jacket structure shown in FIG. FIG. 8 shows an enlarged cross-sectional view when this roll body is cut in a direction perpendicular to the longitudinal direction. As for the roll main body of this comparative example 1, the unevenness | corrugation is not formed in the outer peripheral surface of the inner cylinder 55. FIG. The distance L1 between the outer peripheral surface of the inner cylinder 55 and the inner peripheral surface of the outer cylinder 50 was 15 mm.

When the internal volume V of the jacket portion was determined, it was 0.012 m ³ . Since the internal volume of the jacket portion 52 is set to satisfy PV ≦ 0.04, the value of P is 0.33 MPa. The saturated steam temperature was determined from the value of P and the steam table and found to be 137 ° C.

  The above evaluation results are summarized in Table 2. As shown in Table 2, the internal volume V of the jacket portion 52 is reduced by about 32.5% with respect to the comparative example in the case of Examples 1 and 2, and about 58 with respect to the comparative example 1 in the case of Example 3. In the case of Example 4, the reduction is about 50% with respect to Comparative Example 1. As is apparent from the results shown in Table 2, it can be seen that when the internal volume of the jacket portion 52 decreases, the value of the pressure P increases and the saturated steam temperature of the water vapor increases accordingly. From this, it is considered that the smaller the internal volume of the jacket portion 52, the higher the heat transfer efficiency of the heat medium, and the higher the effect of suppressing temperature unevenness in the longitudinal direction of the roll body surface.

  The induction heating roll of the present invention is a high-frequency induction heating type heating roll that can prevent overheating of the high-frequency coil due to radiant heat from the roll body, and can easily suppress the occurrence of temperature unevenness in the longitudinal direction of the roll body surface at low cost. Can be used for calendar machines, embossing machines, laminator machines, etc.

DESCRIPTION OF SYMBOLS 1, 1a Induction heating roll 2, 4 Induction heating apparatus 3, 3a Roll main body 10 Top plate 11 Screw member 12 Left side plate 13 Front plate 14 Right side plate 15 Back plate 16 Bottom plate 20 High frequency coil 21 Magnetic core (ferrite iron core)
DESCRIPTION OF SYMBOLS 22 Coil wire 23 Electrical insulation resin 24 Electrical insulation resin layer 25 Sensor hole 26 Glass mat 30 Cooling air pipe 30a Hole 31 Screw member 32 Flow direction of cooling air 40 Power supply lead wire 50 Outer shell part of outer roll body (outer cylinder body) )
51, 52 Sealed space (jacket part)
53 Supporting part 54 Opening 55 Inner cylinder 55a Protruding part 56 Inner cylinder internal space 100 Roll body 101 Heat pipe

Claims (5)

A roll body having at least an outer shell portion formed of a metal layer;
An induction heating device that is disposed outside the roll body and induction-heats the roll body using a high frequency coil comprising a magnetic core and a coil wire that winds the magnetic core,
The metal layer is an induction heating roll disposed at a position where the magnetic flux is hardened,
The induction heating device includes a magnetic core made of ferrite core having an E-shaped cross section, and the high-frequency coil and a coil wire winding the magnetic core, a cooling means for flowing cooling air around the high-frequency coil, the cooling The means supplies cooling air into the induction heating device, and the cooling air passes through the front surface of the high frequency coil and is discharged out of the induction heating device to prevent overheating of the high frequency coil due to radiant heat from the roll body. Structure,
The roll body includes an outer cylinder that forms the outer shell portion, and an inner cylinder that is coaxially disposed in the outer cylinder and forms the sealed space between the outer cylinder and the outer cylinder. It is a jacket structure, a heat medium is enclosed in the sealed space, and the internal volume of the sealed space is PV ≦ 0.04 (where PV is pressure (atm) × volume (m ³ )) Is set to be ,
At one end of the roll body, an opening communicating with the internal space of the inner cylinder is formed, and the roll body includes means for flowing a cooling fluid from the opening to the inside of the inner cylinder. An induction heating roll characterized in that temperature control of the roll body and prevention of overheating are possible . The induction heating roll according to claim 1, wherein a plurality of induction heating devices having different lengths are arranged in combination in the longitudinal direction of the roll body. The outer peripheral surface of the inner cylindrical body, an induction heating roll according to claim 1, irregularities are formed. The induction heating roll according to claim 3 , wherein the uneven shape is a spiral shape. 5. The induction heating roll according to claim 4 , wherein the spiral unevenness has a reverse spiral direction with a central portion in a longitudinal direction of the inner cylindrical body as a boundary.

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