JP5557539B2 - Induction heating roller device - Google Patents

Description

  The present invention relates to an induction heat roller device, and more particularly to an induction heat roller device having excellent cooling performance.

  Conventionally, for example, a continuous heat treatment process for a sheet material such as plastic film, paper, cloth, non-woven fabric, synthetic fiber, metal foil, or a continuous material such as a web material, a wire (thread) material, etc., is guided inside the rotating roller body. An induction heating roller device is used in which a heat generation mechanism is arranged to heat the peripheral wall portion of the roller body by an induced current.

  In recent years, for example, there has been a request for changing the heating temperature by the roller body accompanying changing the type of continuous material in a short time. Further, after the end of the stretching process, from the viewpoint of health and safety, the operator cannot leave the site unless the temperature of the roller body is lowered below a certain temperature. For this reason, it is necessary to cool the roller body in as short a time as possible. Furthermore, the induction heating roller device is not only used for heating the continuous material but also used for cooling, and the induction heating roller device needs to have a cooling function.

  In this way, the induction heating roller device is provided with a cooling function. As shown in Patent Document 1, a plurality of cooling media are arranged along the central axis in the circumferential wall of the roller body and at equal intervals in the circumferential direction. It has been considered that a roller body is cooled by providing a passage and circulating the cooling medium in the cooling medium passage.

  However, in order to circulate the cooling medium in the cooling medium passage, it is necessary to supply the cooling medium from the outside through a roller body or a shaft portion (journal portion) integrally provided at the end portion thereof. Since the journal part is a rotating body, a rotary seal mechanism such as a rotary joint or a mechanical seal is required.

  On the other hand, as a configuration not using the rotary seal mechanism, as shown in Patent Document 2, a refrigerant introduction mechanism that introduces a cooling medium into the roller main body, and a cooling medium introduced by the refrigerant introduction mechanism is used for the roller main body. A coolant spraying mechanism that sprays water droplets toward the inner peripheral wall, and cools the roller body by latent heat of vaporization (vaporization heat) when the sprayed cooling medium contacts and vaporizes the inner peripheral wall of the roller body Is considered. The refrigerant spraying mechanism has a discharge pipe extending from one end portion to the other end portion of the inner peripheral wall of the roller body along the axial direction, and is cooled from a discharge port provided on the side wall of the discharge pipe. The medium is sprayed in the form of water droplets.

  However, since the cooling medium is directly sprayed on the inner peripheral wall of the roller body, impurities or non-evaporated components contained in the cooling medium are deposited on the inner peripheral wall of the roller body. In addition, the discharge pipe of the refrigerant spraying mechanism is configured so that the cooling medium is sprayed through the fine holes, so that dust or the like contained in the cooling medium is clogged into the fine holes and the spraying mechanism is clogged. There is a problem in that the induction heating roller device must be disassembled and the discharge pipe or the like must be replaced. Furthermore, in the induction heating roller device, the case where the continuous material is used as a heating roller for the purpose of heating and the case where the continuous material is used as a cooling roller for the purpose of cooling may occur alternately. In this case, when used as a heating roller after being used as a cooling roller, the cooling medium staying in the discharge pipe of the refrigerant spraying mechanism is heated by heat transfer from the roller body, possibly causing boiling. There is.

  In order to solve such problems, the present applicant does not need to provide a rotation seal mechanism in the roller body, and is supported rotatably in order to cool the roller body while suppressing corrosion of the roller body. A roller body, an induction heating mechanism that is held stationary with respect to the roller body inside the roller body, and causes the roller body to generate heat, and a mist-like cooling medium is formed between the roller body and the induction heating mechanism. Development of an induction heating roller device that includes a cooling mechanism that introduces the cooling medium into the gap and discharges the cooling medium to the outside through the gap is underway. In this induction heating roller device, by introducing a mist-like cooling medium into the roller main body, the latent heat of vaporization and the mist-like cooling medium when the mist-like cooling medium evaporates in contact with the inner peripheral wall of the roller main body are generated. The roller body or the induction heating mechanism is cooled by sensible heat when the temperature rises in the roller body and by latent heat when vaporizing and evaporating.

  However, even if the supply of the mist-like cooling medium is stopped after the roller body is cooled to a desired temperature, the mist-like cooling medium remains in the gap portion. If it does so, the residual mist-like cooling medium may condense on the inner peripheral surface of the roller body, and rust may be generated in the roller body. In addition, condensation of the remaining cooling medium by the induction coil of the induction heating mechanism may lead to a decrease in insulation of the induction coil, which may cause a short-circuit accident in the worst case.

JP 2000-353588 A JP 2003-269442 A

  Accordingly, the present invention has been made to solve the above problems all at once, and in an induction heating roller device that cools a roller body and / or an induction heating mechanism using a mist-like cooling medium, the roller body and / or Alternatively, in the stage where the cooling of the induction heating mechanism is stopped, the main intended problem is to prevent the generation of rust inside the roller body caused by the cooling medium in the form of a mist and / or the insulation deterioration of the induction heating mechanism. Is.

That is, an induction heating roller device according to the present invention includes a roller body that is rotatably supported, an induction heating mechanism that is disposed inside the roller body and that causes the roller body to generate heat, and a mist-like cooling medium is used as the roller. A cooling mechanism that is introduced into a gap formed between the main body and the induction heating mechanism and discharges the cooling medium to the outside from the gap, and after the supply of the mist-like cooling medium is stopped, And a gas supply mechanism for supplying a gas and discharging the cooling medium existing in the gap to the outside.

  In such a case, after the supply of the mist-like cooling medium is stopped, the mist-like cooling medium is obtained by supplying the gas to the gap and discharging the cooling medium remaining in the gap to the outside. It is possible to prevent dew condensation and adhesion to the roller body to generate rust. Further, it is possible to prevent insulation deterioration and short circuit accidents due to the condensed cooling medium adhering to the induction heating mechanism. Further, by supplying gas to the gap portion, vaporization and evaporation of the cooling medium already condensed in the gap portion can be promoted, and this also reduces the generation of rust in the roller body and the insulation heat generation mechanism. Can be prevented.

  In order to efficiently discharge the mist-like cooling medium remaining in the gap portion after the supply of the mist-like cooling medium to the outside before dew condensation, the gas supply mechanism is provided with the mist-like cooling medium. It is desirable that gas is supplied to the gap portion for a certain period immediately after the supply is stopped. Further, the gas supply timing may not be immediately after the supply of the mist-like cooling medium is stopped, but the gas may be supplied after a predetermined time has elapsed after the supply stop.

  By supplying the gas after the supply of the mist-like cooling medium is stopped, the mist-like cooling medium in the gap is reduced, and it is not necessary to supply a large amount of gas. On the other hand, even if it is not necessary to discharge the mist-like cooling medium to the outside, it is necessary to evaporate the condensed cooling medium and to prevent further condensation. From this point of view, it is preferable that the gas supply mechanism adjusts the gas flow rate supplied to the gap portion according to the elapsed time from the supply stop of the mist-like cooling medium.

  In order to simplify the configuration of the induction heating roller device using a common cooling mechanism and gas supply mechanism, the cooling mechanism supplies a mist generating device that generates a mist-like cooling medium and compressed air to the mist generating device. And a cooling medium supply circuit for supplying a cooling medium to the mist generating device, wherein the gas supply mechanism is configured using the compressed air supply circuit, and the cooling medium supply circuit is closed. After that, it is desirable to supply the compressed air from the compressed air supply circuit to the gap through the mist generating device.

  Immediately after the supply of the mist-like cooling medium is stopped, the remaining mist-like cooling medium is removed and the condensed cooling medium is removed, and after that period, internal condensation is prevented and condensation is formed. In order to remove the cooling medium, the compressed air supply circuit branches between the compressed air source and the mist generating device, and supplies the mist generating device with high-pressure air for generating a mist-like cooling medium. A first branch path having a high-pressure pressure reducing valve, a second branch path having a low-pressure pressure reducing valve for supplying low-pressure air to the mist generating device, the first branch path, and the second branch path. A switching mechanism for switching, and the gas supply mechanism supplies high-pressure air using the first branch path by the switching mechanism for a certain period immediately after the supply of the mist-like cooling medium to the gap is stopped. After a certain period of time It is preferably configured to supply low pressure air with the second branch passage by the switching mechanism. If it is this, the flow volume of the gas supplied to a clearance gap part can be changed by the simple structure and control which only switch a 1st branch path and a 2nd branch path.

  In order to prevent condensation within the roller body in a state where no mist-like cooling medium is supplied, the low-pressure air is supplied by supplying the mist-like cooling medium to the gap and the mist-like cooling. It is desirable that the operation is continuously performed except for the supply of high-pressure air after the supply of the medium.

  According to the present invention configured as described above, in the induction heating roller device that cools the roller body or the induction heating mechanism using the mist-like cooling medium, in the stage where the cooling of the roller body or the induction heating mechanism is stopped, Generation of rust inside the roller body caused by the cooling medium in the form of mist or insulation deterioration of the induction heating mechanism can be prevented.

It is sectional drawing of the induction heating roller apparatus which concerns on one Embodiment of this invention. It is a schematic diagram which shows the structure of each supply circuit in the same embodiment. It is a schematic diagram which shows the control circuit of the temperature control apparatus in the embodiment. It is a figure which shows the control flow of the temperature control apparatus in the embodiment.

  Hereinafter, an embodiment of an induction heat roller device according to the present invention will be described with reference to the drawings.

  The induction heating roller device 100 according to the present embodiment is, for example, in a continuous heat treatment process of a continuous material such as a sheet material such as a plastic film, paper, cloth, nonwoven fabric, synthetic fiber, and metal foil, a web material, and a wire (thread) material. It is used.

  Specifically, as shown in FIG. 1, this includes a hollow cylindrical roller body 2 that is rotatably supported, and an induction heating mechanism 3 that is accommodated in the roller body 2.

  Journals 41 are attached to both ends of the roller body 2 via seal members S1 such as O-rings. This sealing member S1 prevents a mist-like cooling medium described later from leaking to the outside. Further, the journal 41 is configured integrally with a hollow drive shaft 42, and the drive shaft 42 is rotatably supported by the machine base 52 via a bearing 51 such as a rolling bearing. The roller body 2 is configured to be rotated by a driving force applied from the outside by a rotation driving mechanism (not shown) such as a motor.

The induction heating mechanism 3 includes a cylindrical iron core 31 having a cylindrical shape, and an induction coil 32 wound around the outer peripheral surface of the cylindrical iron core 31. Support shafts 6 are attached to both ends of the cylindrical iron core 31, respectively. Each of the support shafts 6 is inserted into the drive shaft 42 and is rotatably supported with respect to the drive shaft 42 via a bearing 7 such as a rolling bearing. Thereby, the induction heating mechanism 3 is held in a stationary state inside the rotating roller body 2. A lead wire L <b> 2 is connected to the induction coil 32, and an AC power source V for applying an AC voltage is connected to the lead wire L <b> 2 via the power adjustment device 11. A seal mechanism S2 such as an oil seal or a labyrinth seal is provided between the outer surface of the support shaft 6 and the inner surface of the drive shaft 42 so that the mist-like cooling medium does not leak to the outside. Yes.

  With such an induction heating mechanism 3, an alternating magnetic flux is generated when an AC voltage is applied to the induction coil 32, and the alternating magnetic flux passes through the side peripheral wall 21 of the roller body 2. This passage generates an induced current in the roller body 2, and the roller body 2 generates Joule heat by the induced current.

  The induction heat roller device 100 of this embodiment includes a cooling mechanism 8 that cools the roller body 2 and the induction heat generation mechanism 3 with a mist-like cooling medium.

  As shown in FIG. 1, the cooling mechanism 8 introduces a mist-like cooling medium from one end in the axial direction of a substantially cylindrical gap X formed between the roller body 2 and the induction heating mechanism 3. The roller main body 2 and the induction heating mechanism 3 are cooled by discharging the cooling medium from the other axial end of the gap X to the outside of the roller main body 2. The axial direction is the left-right direction of the paper as indicated by the arrows in FIG.

  Specifically, this is a mist generating device 81 that generates a mist-like cooling medium, a compressed air supply circuit 82 that supplies compressed air to the mist generating device 81, and water that is a cooling medium is supplied to the mist generating device 81. The cooling medium supply circuit 83 that performs the cooling medium introduction path 84 that introduces the mist-like cooling medium from the mist generating device 81 from one end in the axial direction of the gap X, and the cooling medium that has passed through the gap X in the axial direction, etc. And a cooling medium discharge path 85 for discharging from the end to the outside.

  The gap portion X has airtightness, and is mainly a substantially cylindrical gap X1 formed by the inner peripheral wall surface of the roller body 2 and the outer peripheral surface of the induction heating mechanism 3, and both ends of the roller body 2. It consists of a substantially annular gap X2 formed by the inner surface of the journal 41 provided in the section and the axial end surface of the induction heating mechanism 3.

  The mist generating device 81 mixes the compressed air from the compressed air supply circuit 82 and the water from the cooling medium supply circuit 83 to generate a mist (mist) cooling medium. This mist-like cooling medium has a particle size that does not vaporize and evaporate immediately after being injected, and falls by gravity in the process of being transported with air, or collides with a wall surface at a bent portion of the flow path. The particle size is such that it does not liquefy. Specifically, the mist-like cooling medium has a particle size in the range of 30 to 100 μm.

  The compressed air supply circuit 82 is provided on a compressed air source 821, a compressed air pipe 822 having one end connected to the compressed air source 821, and the other end connected to the mist generating device 81, and the compressed air pipe 822. An on-off valve 823 that controls the supply and stop of compressed air to the mist generating device 81 and a flow rate adjusting valve 824 that is provided downstream of the on-off valve 823 and adjusts the flow rate of the compressed air supplied to the mist generating device 81 ( In this embodiment, a pressure reducing valve) is provided. The specific configuration of the compressed air supply circuit 82 and the specific control mode of the temperature control device TC for the on-off valve 823 will be described later.

  The cooling medium supply circuit 83 is provided on the water storage tank 831, a cooling medium pipe 832 having one end connected to the water storage tank 831 and the other end connected to the mist generating device 81, and the cooling medium pipe 832. An on-off valve 833 for controlling the supply and stop of the cooling medium to the device 81 and a flow rate adjusting valve 834 (downstream valve 833 provided downstream of the on-off valve 833 for adjusting the flow rate of the cooling medium supplied to the mist generating device 81) In this embodiment, a pressure reducing valve) is provided. The on-off valve 833 is an electromagnetic valve that opens and closes by an ON / OFF signal from the temperature control device TC, and a specific control mode of the temperature control device TC will be described later.

  The cooling medium introduction path 84 is configured by a hollow portion 61 formed along a central axis inside a support shaft 6 (hereinafter, this support shaft is referred to as 6A) provided at one end of the induction heating mechanism 3. ing. Specifically, the hollow portion 61 is a space having a substantially cylindrical shape formed coaxially with the central axis of the support shaft 6A.

  The hollow portion 61 is opened at the outer end surface of the support shaft 6A, and the discharge port 81s of the mist generating device 81 is attached to the opening portion so as to face the hollow portion 61. Specifically, the discharge port 81 s of the mist generating device 81 is attached on the central axis of the hollow portion 61. In this way, the mist generating device 81 is provided at a position where it can be easily attached to and detached from the induction heat roller device 100 when there is a malfunction such as clogging. In addition, the opening part of the hollow part 61 and the mist production | generation apparatus 81 are attached so that attachment or detachment is possible via the seal structure (not shown).

  The hollow portion 61 communicates with the gap portion X through a plurality of through holes 61H at the base end portion (end portion on the induction heating mechanism 3 side) of the support shaft 6A. The through hole 61H forms an opening on the downstream side of the cooling medium introduction path 84. The through holes 61H are arranged at one end in the axial direction of the gap X (the gap X2 in the present embodiment), and are formed at equal intervals in the radial direction on the support shaft 6A.

  The cooling medium discharge path 85 is configured by a cooling medium discharge pipe 85T provided along the inside of a support shaft 6 (hereinafter, this support shaft is referred to as 6B) provided at the other end of the induction heating mechanism 3. ing. The cooling medium discharge pipe 85T is provided by being inserted into a hollow portion 62 formed along the center axis inside the support shaft 6B, and is provided at the base end portion (end portion on the induction heating mechanism 3 side) of the support shaft 6B. , The opening is directed toward the gap X, and the opening is the upstream opening of the cooling medium discharge path 85. And this upstream opening is arrange | positioned in the axial direction other end part (gap X2 in this embodiment) of the clearance gap X. FIG. In addition, the lead wire L2 connected to the induction coil 32 described above is also provided in the hollow portion 62 of the support shaft 6B.

  Further, a decompression device 9 for decompressing the gap X is provided on the cooling medium discharge pipe 85T outside the support shaft 6B. The decompression device 9 decompresses the inside of the gap X by sucking the air upstream of the cooling medium discharge pipe 85T and discharging it to the outside. As a result, the gap X is depressurized, the mist-like cooling medium introduced into the gap X is easily evaporated, the roller body 2 is easily cooled, and the vaporized cooling medium is contained in the roller body 2. It is possible to prevent condensation on the peripheral wall and the induction heating mechanism 3. Further, the decompression device 9 is configured so that the mist-like cooling medium passes through the gap X at a predetermined flow rate. Specifically, by setting the flow rate of the mist-like cooling medium in the gap portion X to 0.3 m / s or higher, high thermal conductivity can be obtained, and the cooling efficiency of the roller body 2 is greatly structured. Can do.

  Further, since the mist-like cooling medium is supplied to the gap portion X as described above, the surface of the member forming the gap portion X, specifically, the inner peripheral wall surface of the roller body 2, the inner surface of the journal 41, and the support shaft 6 Rust prevention treatment is applied to the outer peripheral surface. In addition, a waterproof film F is provided on the outer peripheral surface of the induction heat generating mechanism 3 over substantially the entire surface in order to prevent electrical failure due to the cooling medium. This waterproof film F is necessary when there is a concern about condensation due to the relationship between the dew point temperature determined by the mist concentration inside the roller body 2 and the induction heating mechanism 3 during the cooling operation. If the temperature is clearly above the dew point temperature, it can be omitted.

  By introducing the mist-like cooling medium into the roller main body 2 by such a cooling mechanism 8, the latent heat of vaporization and the mist-like heat generated when the mist-like cooling medium contacts the inner peripheral wall of the roller main body 2 and evaporates. The roller body 2 or the induction heating mechanism 3 can be cooled by the sensible heat when the temperature of the cooling medium rises in the roller body 2 and the latent heat when it evaporates and evaporates. Then, the mist-like cooling medium is introduced from the axial end of the gap portion X formed between the roller body 2 and the induction heat generating mechanism 3 and is cooled from the axial end of the gap portion X. By discharging the medium to the outside of the roller body 2, the mist-like cooling medium can be spread over the entire gap X. Moreover, since the mist-like cooling medium is used, the cooling medium in contact with the roller body 2 can be reduced, and corrosion of the inner wall of the roller body 2 and accumulation of impurities can be suppressed. For example, when the temperature of the roller body 2 of the induction heating roller device is naturally cooled from 200 ° C. to 150 ° C., it takes about 30 minutes. By using this cooling mechanism 8, the temperature of the roller body 2 is changed from 200 ° C. to 150 ° C. The cooling time can be reduced to about 10 minutes.

  Thus, after the supply of the mist-like cooling medium to the gap X by the cooling mechanism 8 is stopped, the induction heating roller device 100 of the present embodiment supplies the cooling medium removal gas into the gap X, A gas supply mechanism for discharging the cooling medium present in the gap X to the outside is further provided.

  This gas supply mechanism is configured by using a part of the configuration of the cooling mechanism 8. Specifically, the gas supply mechanism is configured using a compressed air supply circuit 82 and a cooling medium introduction path 84. After the cooling medium supply circuit 83 of the cooling mechanism 8 is closed, the compressed air from the compressed air supply circuit 82 is supplied. The mist generating device 81 and the cooling medium introduction path 84 are supplied to the gap X. The air supplied to the gap X is discharged to the outside through the cooling medium discharge path 85.

  As shown in FIG. 1 and FIG. 2, the compressed air supply circuit 82 constituting the gas supply mechanism has a compressed air pipe 822 branched between the compressed air source 821 and the mist generating device 81. A first branch passage 822A having a high-pressure pressure reducing valve 824A for supplying high-pressure air for generating a mist-like cooling medium, and a second low-pressure pressure reducing valve 824B for supplying low-pressure air to the mist generating device 81. It has a branch path 822B and a switching mechanism that switches between the first branch path 822A and the second branch path 822B. Note that the flow rate of the low-pressure air supplied from the second branch path 822B is set smaller than the flow rate of the high-pressure air supplied from the first branch path 822A, and is set to about 10%, for example.

  The switching mechanism of the present embodiment is configured by a first on-off valve 823A and a second on-off valve 823B provided on the first branch path 822A and the second branch path 822B, respectively. The first on-off valve 823A and the second on-off valve 823B are electromagnetic valves that are opened and closed by an ON / OFF signal from the temperature control device TC. In addition, as a switching mechanism, you may comprise by providing a three-way switching valve in the branch point or confluence | merging point of 1st branch path 822A and 2nd branch path 822B.

  Next, temperature control of the induction heating roller device 100 of the present embodiment will be described with reference to FIGS. 3 and 4 together with operations of the cooling mechanism 8 and the gas supply mechanism. 3 is a control circuit diagram of the compressed air supply circuit 82 and the cooling medium supply circuit 83 in the temperature control device TC. FIG. 4 shows the temperature of the roller body 2, the induction heating mechanism 3 (induction coil power), It is a figure which shows the control flow which shows a corresponding relationship with the operation | movement of the compressed air supply circuit 82 (ON / OFF of the on-off valve 823A and 823B) and the cooling medium supply circuit 83 (ON / OFF of the on-off valve 833).

  The temperature control device TC receives a detection signal of a temperature sensor 2T embedded in the peripheral wall of the roller body 2 via a temperature detection device (specifically, a rotary transformer) 10, and detects a detection temperature (PV) indicated by the detection signal. Then, a predetermined set temperature (SV) is compared, and power supply to the induction coil 32 and supply of the mist-like cooling medium are controlled so that the detected temperature (PV) becomes the set temperature (SV). The temperature control device TC outputs a signal to be input to the induction coil 32 to the power adjustment device 11 configured using, for example, a thyristor, according to the difference between the detected temperature (PV) and the set temperature (SV). .

  Further, when the detected temperature (PV) is higher than the set temperature (SV), the temperature controller TC supplies compressed air to supply the mist-like cooling medium to the gap X and cool the roller body 2. An ON signal is output to the first on-off valve 823A on the first branch path 822A of the circuit 82 and the on-off valve 833 on the cooling medium supply circuit 83. FIG. 4 shows a mode in which the mist-like cooling medium is supplied to the gap X when the detected temperature (PV) is higher than the set temperature (SV) + 1 ° C. Accordingly, the first on-off valve 823A and the on-off valve 833 are opened, and the compressed air and the cooling medium are supplied to the mist generating device 81, so that a mist-like cooling medium is generated.

  Thereafter, the temperature controller TC stops supplying the mist-like cooling medium when the roller body 2 is cooled by the mist-like cooling medium and the detected temperature (PV) falls below the set temperature (SV). An OFF signal is output to the first on-off valve 823A and the on-off valve 833. At this time, the on-off valve 823A on the first branch path 822A closes with a delay of a preset time by the delay timer T1, and until then, only high-pressure air passes through the mist generating device 81 in the gap X. Will continue to be supplied. That is, the high-pressure air is supplied to the gap X for a certain period immediately after the supply of the mist-like cooling medium is stopped, and the mist-like cooling medium remaining in the gap X can be discharged to the outside and the condensation has already occurred. The cooling medium (condensation water) is evaporated and discharged to the outside. Further, by supplying the high-pressure air immediately after the stop, the time during which the remaining mist-like cooling medium is condensed is shortened as much as possible.

  Then, the temperature controller TC outputs an ON signal to the second on-off valve 823B on the second branch 822B when the first on-off valve 823A on the first branch 822A is closed. As a result, the second on-off valve 823B is opened, and only low-pressure air is supplied into the gap X via the mist generating device 81. Thus, high-pressure air is supplied using the first branch path 822A by the switching mechanism for a certain period immediately after the supply of the mist-like cooling medium to the gap X is stopped, and after the certain period has elapsed, the switching mechanism The second branch path 822B is used to supply low pressure air. In other words, the gas flow rate supplied to the gap X is adjusted in two steps (high pressure air and low pressure air) according to the elapsed time from the supply stop of the mist-like cooling medium. In this way, by supplying low-pressure air after a certain period of time, internal condensation can be prevented and the condensed cooling medium can be removed.

  Thereafter, until the supply operation of the mist-like cooling medium is started, that is, until the detection temperature (PV) exceeds the set temperature (SV) again and the cooling operation is started, the temperature control device TC The ON signal is continuously output to the second on-off valve 823B so that the low pressure air is continuously supplied to the gap X. That is, the supply of the low-pressure air is configured to be continuously performed at any time other than the supply of the mist-like cooling medium to the gap X and the supply of the high-pressure air after the supply of the mist-like cooling medium.

<Effect of this embodiment>
According to the induction heating roller device 100 according to the present embodiment configured as described above, the cooling medium remaining in the gap X by supplying the gas to the gap X after the supply of the mist-like cooling medium is stopped. By discharging to the outside, it is possible to prevent the mist-like cooling medium from condensing and adhering to the roller body 2 to generate rust. Further, it is possible to prevent insulation deterioration and short circuit accidents due to the condensed cooling medium adhering to the induction heating mechanism 3. Further, by supplying gas to the gap X, it is possible to promote vaporization and evaporation of the cooling medium (condensation water) that has already condensed in the gap X, which also generates rust inside the roller body 2. And the insulation fall of the induction heating mechanism 3 can be prevented.

<Other modified embodiments>
The present invention is not limited to the above embodiment.

  For example, in the above-described embodiment, the gas supply mechanism is configured by using a part of the configuration of the cooling mechanism, and the configuration of the induction heat roller device is simplified. It is good also as another structure. At this time, as the gas supplied by the gas supply mechanism, it is conceivable to use an inert gas such as nitrogen gas or argon gas in addition to air.

  In the above embodiment, the two-stage supply of high-pressure air and low-pressure air is performed after the supply of the mist-like cooling medium is stopped. In addition, the number of branches of the compressed air supply circuit is set to three or more. In addition, by using different pressure reducing valves in the respective branch paths, the air may be supplied in three or more stages according to the elapsed time since the supply of the mist-like cooling medium is stopped.

  In the above embodiment, a cooling mechanism (gas supply mechanism) is provided on one end side of the journal, and a rotary transformer is provided on the other end side. When the rotary drive mechanism is attached to one end of the journal, the configuration becomes complicated. , It can be difficult to apply. In this case, it is desirable to provide the cooling mechanism at the same end as the side where the rotary transformer is equipped.

  In the above-described embodiment, the dual-support induction heating roller device has been described. However, the invention can also be applied to an induction heating roller device that supports only one of the journals at two points in a freely rotatable manner. Furthermore, the present invention can be applied to a so-called cantilever induction heating roller device.

  In addition, the cooling mechanism is connected to the mist generating device for generating a mist-like cooling medium, and is connected to the mist generating device in the axial direction of a substantially cylindrical gap formed between the roller body and the induction heating mechanism. A cooling medium supply pipe that has a plurality of cooling medium supply ports arranged along the gap and supplies a mist-like cooling medium to the gap may be provided. At this time, the gas supply mechanism is configured using a compressed air supply circuit and a cooling medium supply pipe.

  In addition, in the embodiment, the mist-like cooling medium is introduced from one axial end of the gap and discharged from the other axial end, but is introduced from the axial one end of the gap. And you may make it discharge | emit from the same axial direction one end part.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Induction heating roller apparatus 2 ... Roller main body 3 ... Induction heating mechanism X ... Gap part 8 ... Cooling mechanism 81 ... Mist production | generation apparatus 82 ... Compressed air supply circuit 822A ..First branch path 822B ... second branch path 824A ... high pressure reducing valve 824B ... low pressure reducing valve 83 ... cooling medium supply circuit

Claims (6)

A roller body rotatably supported;
An induction heating mechanism that is disposed inside the roller body and causes the roller body to generate heat;
A cooling mechanism that introduces a mist-like cooling medium into a gap formed between the roller body and the induction heating mechanism, and discharges the cooling medium from the gap to the outside;
An induction heating roller device comprising: a gas supply mechanism that supplies gas into the gap and discharges the cooling medium existing in the gap after the supply of the mist-like cooling medium is stopped.   The induction heat roller device according to claim 1, wherein the gas supply mechanism supplies gas to the gap portion for a certain period immediately after the supply of the mist-like cooling medium is stopped.   The induction heating roller device according to claim 1 or 2, wherein the gas supply mechanism adjusts a gas flow rate supplied to the gap portion according to an elapsed time from the supply stop of the mist-like cooling medium. The cooling mechanism includes a mist generating device that generates a mist-like cooling medium, a compressed air supply circuit that supplies compressed air to the mist generating device, and a cooling medium supply circuit that supplies a cooling medium to the mist generating device. Have
The gas supply mechanism is configured using the compressed air supply circuit, and after the cooling medium supply circuit is closed, the compressed air from the compressed air supply circuit is transferred to the gap through the mist generating device. The induction heating roller device according to claim 1, 2 or 3, which is supplied. The compressed air supply circuit is branched between a compressed air source and a mist generating device, and has a high pressure reducing valve for supplying high pressure air for generating a mist-like cooling medium to the mist generating device. A branch path, a second branch path having a low pressure reducing valve for supplying low pressure air to the mist generating device, and a switching mechanism for switching the first branch path and the second branch path,
The gas supply mechanism supplies high-pressure air using the first branch path by the switching mechanism for a certain period immediately after the supply of the mist-like cooling medium to the gap is stopped, and after the certain period has elapsed, The induction heating roller device according to claim 4, wherein the switching mechanism is configured to supply low-pressure air using the second branch path. The supply of the low-pressure air is continuously performed except for the supply of the mist-like cooling medium to the gap and the supply of high-pressure air after the supply of the mist-like cooling medium. The induction heating roller device as described.