JP2019133902A - Induction heating coil - Google Patents

Abstract

To provide an induction heating coil capable of easily obtaining a highly accurate heating state of an object to be heated by measuring the heating temperature of a predetermined portion such as a center portion of the inner surface and the outer surface of an object to be heated during induction heating in a heated state easily and accurately by integrally arranging a radiation temperature sensor at a predetermined position of a heating coil.SOLUTION: An induction heating coil includes a coil portion including a coil conductor wound a predetermined number of times with a predetermined gap and a bottomed cylindrical coil cover covering the outer periphery of the coil conductor, a coil support portion that supports the open base end side of the coil portion and has a cooling water supply portion that can supply cooling water into the coil cover, and a radiation temperature sensor that is integrally disposed on the coil support portion and in which a probe capable of receiving radiated light from an object to be heated is directed to the inner diameter surface of the object to be heated. Further, the radiation temperature sensor is arranged so as to be movable and adjustable in the coil conductor direction.SELECTED DRAWING: Figure 1

Description

  The present invention is, for example, inserted into a shaft hole of a large metal bolt (object to be heated) for tightening a flange in a steam turbine chamber and induction heating the inner surface (inner diameter surface) of the shaft hole, or a heating space. For example, the present invention relates to an induction heating coil that is used when a columnar workpiece or a cylindrical workpiece (object to be heated) is arranged and the outer surface (outer diameter surface) of the workpiece is induction heated.

  Conventionally, an induction heating coil for induction heating an inner surface of an object to be heated is disclosed in, for example, Patent Document 1. This induction heating coil (inner diameter surface induction heating coil) is made of an insulator, a base member having an inner diameter protruding portion formed at the central portion of the plate-shaped portion, and a large diameter bulging portion and a small outer diameter protrusion. A hollow case made of a cover member provided with a portion and a heating member obtained by winding a thin plate-like conductor disposed inside the case a predetermined number of times, supplying a high-frequency current to the heating member and Cooling water is supplied into the arranged case to inductively heat the inner diameter surface of the heated member.

  Moreover, the induction heating coil which induction-heats the outer surface of a to-be-heated material is disclosed by patent document 2, for example. The induction heating coil includes a plurality of coil portions each obtained by winding a copper round pipe a plurality of times, and a pipe-shaped linear conductor that connects both ends of the coil portion. In a state where the object to be heated is arranged, a high frequency current is supplied to the coil part, and cooling water is circulated and supplied into the pipe of the coil part to inductively heat the object to be heated.

Japanese Patent No. 543127 Japanese Patent No. 3621685

  However, in these induction heating coils, in order to induction heat the inner surface and outer surface of the object to be heated with high accuracy, the temperature of the heated part of the object to be heated is measured with a non-contact type radiation temperature sensor, When a predetermined temperature is reached according to the object to be heated, energization (induction heating) to the heating coil is stopped. However, in the conventional induction heating coil, the radiation temperature sensor is arranged separately from the heating coil and outside the heating coil. In this configuration, the heating coil is inserted into the shaft hole when measuring the temperature of the inner surface. Therefore, the temperature of the end portion such as the upper end portion where the heating coil of the shaft hole of the article to be heated is inserted must be measured in a state where the heating coil is once removed from the shaft hole.

  Also, in the case of measuring the temperature of the outer surface, if there is a gap in the winding portion of the heating coil, it is possible to measure the temperature of the central portion of the outer surface of the object to be heated using this gap, etc. If there is no gap or the like in the coil winding part, it is difficult to measure the temperature. Similar to the temperature measurement of the shaft hole described above, with the heating coil removed from the heated part, the axial direction of the heated object The actual situation is measuring the temperature of the edges of the slab.

  By the way, the applicant of the present invention has firstly introduced an induction heating coil (Japanese Patent Application No. 2017-121138) for induction heating of the inner surface of the object to be heated and an induction heating coil (Japanese Patent Application No. 2007-151138) for induction heating the outer surface of the object to be heated. 2017-126824). Then, as a result of earnest research, these induction heating coils are provided with a structure that is cooled in an immersed state in the cooling water in which the coil section circulates, so the radiation temperature sensor is simply disposed outside the heating coil. Then, it became difficult to accurately measure the heating temperature inside the part near the center in the longitudinal direction of the object to be heated, and it became clear that the temperature measurement work was very troublesome. This is an improvement of the point.

  That is, an object of the present invention is a heating coil that is cooled in an immersed state in the cooling water flowing through the coil portion, for example, by arranging a radiation temperature sensor having a predetermined function integrally at a predetermined position of the heating coil. However, it is easy to accurately and accurately measure the heating temperature of a predetermined part such as the inner surface of the object to be heated during induction heating or the central part of the outer surface in the heated state. It is to provide an induction heating coil that can be obtained.

  In order to achieve this object, the invention according to claim 1 of the present invention is a bottomed cylindrical coil covering a coil conductor wound a predetermined number of times with a predetermined gap and covering an outer peripheral side of the coil conductor. A coil part having a cover, a coil support part having a cooling water supply part that supports the open base end side of the coil part and capable of supplying cooling water into the coil cover, and a coil support part are provided integrally with the coil support part. And a radiation temperature sensor that is provided and capable of receiving radiated light from the object to be heated is directed to the inner diameter surface of the object to be heated.

  In the invention according to claim 2, the coil support part is connected and connected to a holder part made of a pair of copper plates press-fixed via an insulating plate, and the cooling water supply part is provided on an outer surface of the holder part. A cooling pipe capable of supplying cooling water is fixed, and a connecting portion to which a transformer can be connected is provided on the proximal end side of the holder portion.

  According to a third aspect of the present invention, there is provided a coil portion in which a predetermined number of coil conductors are wound, an inner side, an outer side, and both side surfaces of the coil portion with airtightness, and an object to be heated on the inner peripheral side. A coil cover having a heating space into which the coil cover can be inserted, a cooling water supply unit capable of circulating and supplying cooling water into the internal space of the coil cover, and the heating at a predetermined position in the axial direction of the coil cover. A probe capable of receiving radiated light from a heated object inserted and disposed in the space includes a radiation temperature sensor directed to the outer peripheral surface of the heated object.

  The invention according to claim 4 is characterized in that the radiation temperature sensor is arranged so as to be movable and adjustable in the coil conductor direction. In the invention according to claim 5, the coil conductor of the coil portion is formed by winding a flat conductor or a solid conductor, and these are supplied into the coil cover from the cooling water supply portion. It is configured to be capable of cooling in a state immersed in cooling water.

  According to the first aspect of the present invention, the coil conductor includes a coil part covered with a coil cover, and a cooling water supply part that supports the coil part and can supply cooling water into the coil cover. Since the coil support part and the radiation temperature sensor that is integrally disposed on the coil support part and directed to the inner diameter surface of the object to be heated are provided, the coil conductor is cooled in the immersed state in the cooling water flowing through the coil cover. Even with a heating coil that is heated, the probe of the radiation temperature sensor can accurately measure the heating temperature inside the heated object during induction heating with high accuracy and in the heated state. In addition, it is possible to easily obtain a highly accurate heating state.

  Further, according to the invention described in claim 2, in addition to the effect of the invention described in claim 1, the coil support portion is a holder in which a cooling pipe capable of supplying cooling water to the cooling water supply portion is fixed to the outer surface. Since the connecting portion that is connected and connected to the distal end side of the portion and to which the transformer can be connected is provided on the proximal end side of the holder portion, the heating coil can be reliably and easily connected to the output terminal of the transformer. Even in the case of a bolt shaft hole in which the indoor flange cannot be moved, the heating coil and the transformer can be arranged in the vicinity of the bolt, induction heating can be performed, and a heating coil excellent in usability can be obtained.

  Further, according to the invention described in claim 3, the inside, outside and both side surfaces of the coil portion around which the coil conductor is wound are covered with airtightness, and the heating target can be arranged on the inner peripheral side. A coil cover having a space, a cooling water supply unit capable of circulatingly supplying cooling water into the internal space of the coil cover, and a heated object disposed in a predetermined position in the axial direction of the coil cover and inserted in the heating space Since the probe capable of receiving the radiation from the object has a radiation temperature sensor directed to the outer surface of the object to be heated in the heating space, the coil conductor is cooled in an immersed state in the cooling water flowing through the coil cover. Even so, with the probe of the radiation temperature sensor, the heating temperature at the specified position on the outer surface of the object to be heated during induction heating can be accurately measured with high accuracy in the heated state. Easy heating Rukoto becomes possible.

  According to the invention described in claim 4, in addition to the effects of the invention described in claims 1 to 3, the radiation temperature sensor is disposed so as to be movable and adjustable in the coil conductor direction. It is possible to measure the temperature of a predetermined portion of the inner diameter surface or the outer diameter surface with higher accuracy.

  According to the invention described in claim 5, in addition to the effects of the invention described in claims 1 to 4, the coil conductor of the coil portion is formed by winding a flat copper pipe or a solid conductor, Since these are configured to be cooled in the immersed state by the cooling water supplied from the cooling water supply unit into the coil cover, the heating coil is heated by the coil conductor that can be effectively cooled in the immersed state in the cooling water. It is possible to obtain a heating coil with excellent usability such that the efficiency can be sufficiently increased and various types of coil conductors can be used.

The perspective view which shows 1st Embodiment of the induction heating coil concerning this invention. The front view The plan view Sectional drawing which shows an example of the coil part The perspective view which shows 2nd Embodiment of the induction heating coil concerning this invention. The perspective view of the coil part Cross section of the coil

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
1 to 4 show a heating coil for internal heating, which is a first embodiment of an induction heating coil according to the present invention. As shown in FIGS. 1 to 3, the induction heating coil 1 (referred to as a heating coil 1) includes a coil portion 2, a coil support portion 3 that supports the proximal end side of the coil portion 2, and the coil support portion 3. A connected holder portion 4 and the like are provided.

  As shown in FIG. 4, the coil portion 2 is formed of a coil conductor 2a obtained by winding a flat pipe into a coil shape a predetermined number of times, and an insulator such as a bake material covering the outer peripheral side and the distal end side of the coil conductor 2a. The bottomed cylindrical coil cover 2b is provided. At this time, as the coil conductor 2a, a crushed copper pipe having a flat gap inside is used by crushing a round copper pipe as a conductor in the diameter (cross section) direction. Is formed in a coil shape by winding a predetermined number of times along.

  Further, the distal ends of a pair of round copper pipes 2c and 2d are fixed by brazing to the proximal end and the distal end, which are both ends of the coil conductor 2a, respectively. As shown in FIG. 2, the base end portion extends upward by a predetermined dimension and protrudes on the coil support portion 3. At this time, as shown in FIG. 4, one copper pipe 2c is disposed in a state of opening downward on the open side of the coil cover 2b, and its lower end side surface and the coil conductor 2a communicate with each other through a communication hole. It is said that. The other copper pipe 2d is inserted into the axial center position of the coil conductor 2a, and the lower end side surface and the coil conductor 2a are in communication with each other through a communication hole.

  A high-frequency current is supplied to the coil conductor 2a through the copper pipes 2c and 2d as described later, and cooling water is circulated and supplied to the gap in the coil conductor 2a and the coil cover 2b. Moreover, the cooling water supply part of this embodiment is formed by the copper pipes 2 c and 2 d supported by the coil support part 3. The coil conductor 2a is not limited to the crushed copper pipe having a gap inside, but a solid appropriate conductor having no gap inside, for example, a copper thin plate can also be used. The cooling water supplied from the copper pipes 2c and 2d is configured to be circulated and supplied only into the coil cover 2b.

  As shown in FIGS. 1 to 3, the coil support portion 3 includes a cover fixing nut 3a, a coil fixing plate 3b, a sensor support plate 3c, a divided coil clamp 3d, etc., each formed of an insulating material. ing. And the base end part of the said coil part 2 is supported via the copper pipes 2c, 2d, etc. by the cover fixing nut 3a and the coil fixing plate 3b. The holder portion 4 is connected and fixed to the base end portions of the copper pipes 2c and 2d.

  The holder portion 4 has a pair of copper plates 4a that are press-fitted and fixed via insulating plates 4b, and a connection that can be electrically and mechanically connected to an output transformer (not shown) at the base end of each copper plate 4a. Terminal portions 4c are provided as portions. A cooling pipe 4d made of a square copper pipe capable of cooling the copper plate 4a itself is brazed and fixed to the outer surface of each copper plate 4a, and the end of the cooling pipe 4d communicates with the copper pipes 2c and 2d. Each hose joint 4e is fixedly brazed to the base end portion of each cooling pipe 4d.

  A radiation temperature sensor 6 is attached to the sensor support plate 3c so as to be directed in the vertical direction. The radiation temperature sensor 6 includes a probe 6a having a disk-shaped transparent sapphire window bonded to the tip of a cylindrical housing with a sealing structure and having an optical transmission path therein, and a control unit including a light detection unit 6b and the like. The radiation temperature sensor 6 is supported by the sensor support plate 3c by fitting the cylindrical probe 6a into the vertical fitting hole of the sensor support plate 3c.

  In addition, the coil fixing plate 3b and the cover fixing nut 3a positioned below corresponding to the fitting hole of the sensor support plate 3c are penetrated in the vertical direction (or the outer periphery through which radiated light can be transmitted (passed)). Each of the through recesses formed on the surface is provided. The radiation temperature sensor 6 is disposed so as to be movable in the vertical direction manually or automatically with respect to the fitting hole of the sensor support plate 3c and the through hole such as the coil fixing plate 3b. The light receiving position can be set to a predetermined value. Moreover, the radiation temperature sensor 6 is not limited to the structure demonstrated above, The sensor of the appropriate structure which can detect temperature and can measure temperature can be used.

  The pair of coil clamps 4d are detachably fixed to the upper surface of the sensor support plate 3c, and the base end portions of the radiation temperature sensor 6 and the copper pipes 2c and 2d are supported. The configuration of the coil support portion 3 is not limited to the above example, and the coil portion 2, the radiation temperature sensor 6 and the holder portion 4 can be supported, for example, the coil fixing plate 3b has the function of the sensor support plate 3c. An appropriate configuration can be adopted.

  As shown in FIGS. 1 and 2, the heating coil 1 configured as described above connects the pair of terminal portions 4 d of the holder portion 4 to the secondary side terminals of an output transformer (not shown) and the coil portion 2. Is inserted into a shaft hole Wa of a metal bolt W (to be heated, hereinafter referred to as a bolt W) from above. The radiation temperature sensor 6 is set at a position where the probe 6a is directed toward the inner surface of the shaft hole Wa of the bolt W and the probe 6a can accurately receive the radiated light from the shaft hole Wa of the bolt W.

  The output transformer is electrically connected at its primary side to the transistor inverter of the high-frequency induction heating device via a flexible connection cable (not shown), and a pair of hose joints 4e of the holder portion 4 of the heating coil 1 is used. However, it is connected to a cooling water supply device disposed in, for example, the same induction heating device via an appropriate hose. In this state, when the transistor inverter and the cooling water supplier are operated, high frequency current is supplied (powered) from the transistor inverter to the coil conductor 2 via the output cable, the output transformer, the holder 4 and the copper pipes 2c and 2d. The

  When a high-frequency current is supplied to the coil conductor 2, an eddy current is induced on the inner surface of the shaft hole Wa of the bolt W, and the inner surface 7a is induction-heated. At this time, since the coil conductor 2 is a flat copper pipe, the surface area of the conductor facing the inner surface of the shaft hole Wa is larger than that of, for example, a mere round copper pipe, that is, from the coil conductor 2 toward the inner surface of the shaft hole Wa. The number of magnetic field lines to be irradiated can be increased, and an efficient induction heating state can be obtained.

  The heating temperature of the inner surface of the shaft hole Wa by this induction heating is sequentially measured by the radiation temperature sensor 6, and the signal is input to a control unit (not shown) of the high frequency induction heating device. When the measured temperature reaches a preset temperature preset in the control unit, for example, the operation of the transistor inverter is stopped, but the preset temperature is maintained. As a result, the inner surface of the shaft hole Wa of the bolt W is induction-heated at a predetermined temperature.

  At this time, the radiation temperature sensor 6 that receives the radiation is integrally disposed on the coil support portion 3 of the heating coil 1, and the direction of the radiation is directed to the outer periphery of the coil cover 2b and the shaft hole of the bolt W. Since it is set between the inner surfaces (inside) of Wa and is set so that the radiation inside the shaft hole Wa can be received accurately, the heating coil 1 remains set (in the heated state) and the inside of the shaft hole Wa is set. The heating temperature at a desired position (for example, a position close to the center in the axial direction) can be successively measured with high accuracy, and substantially the entire inner surface of the shaft hole Wa can be heated substantially uniformly at the desired temperature.

  On the other hand, when the cooling water supply device is operated substantially simultaneously with the transistor inverter, for example, the cooling water is supplied into the coil cover 2b through the one hose joint 4e, the one cooling pipe 4d, and the copper pipe 2c. And the coil conductor 2a is cooled. The cooling water is returned to the cooling water supply device via the copper pipe 2d, the other cooling pipe 4d, the other hose joint 4e, and the like. Further, part of the cooling water supplied through the copper pipe 2c also flows into the gap between the coil conductors 2a through the communication holes of the copper pipes 2c and 2d, so that the coil conductor 2a is also cooled from the inside. Is done.

  As a result, two cooling water flow paths are formed in the heating coil 1, a flow path through which the cooling water flows in the coil conductor 2 a and a flow path in which the cooling water flows in the coil cover 2 b. At this time, since the cooling water flows through the coil cover 2b and cools the coil conductor 2a, the coil conductor 2a is cooled while immersed in the cooling water, and the cooling water reliably contacts the flat interior and the surface. However, it cools and the heat_generation | fever of the coil conductor 2a is suppressed efficiently. In addition, the flow path of the cooling water in the case where the thin copper plate having no gap as described above is used as the coil conductor 2a becomes one system that circulates only in the coil cover 2b. The cooling water comes into contact with the entire outer peripheral surface of the coil conductor 2a to be cooled.

  Then, the bolt W whose inner surface of the shaft hole Wa is heated by the heating coil 1 in this way is heated almost uniformly at the heating temperature suitable for the extraction work, so that the bolt is removed. Work can be done easily. In addition, when the bolt W is extracted, the heating coil 1 is directly fixed to the output terminal of the output transformer that is small and easy to carry. Therefore, movement, installation, and operation of a plurality of adjacent bolts W are started. For example, from the flange in the steam turbine chamber fixed with a large number of bolts W, the bolts W can be easily extracted in a short time.

  Thus, according to the heating coil 1, the probe 6a of the radiation temperature sensor 6 that receives the radiated light is provided on the coil support portion 3 that supports the coil portion 2 in which the coil conductor 2a is incorporated in the coil cover 2b. Even if it is the heating coil 1 in which the coil conductor 2a is cooled in the immersed state in the cooling water flowing through the coil cover 2b, for example, because the coil conductor 2a is integrally disposed in a state of being oriented inside the shaft hole Wa of the bolt. The heating temperature inside the inner surface of the shaft hole Wa of the bolt W during induction heating can be accurately measured without removing the heating coil 1 from the shaft hole Wa, and the bolt W has high accuracy. The heating state can be easily obtained.

  In particular, since the radiation temperature sensor 6 is arranged so as to be movable and adjustable in the direction of the coil conductor 2a, the temperature of a predetermined portion inside the shaft hole Wa of the bolt W can be measured with higher accuracy, and heating with higher accuracy can be performed. A state can be obtained, and various bolts W and other work shaft holes can be accommodated, and the versatility of the heating coil 1 can be improved.

  Furthermore, the coil support portion 3 is connected and connected to the distal end side of the holder portion 4 having the cooling pipe 4d for circulating cooling water on the outer surface, and a terminal portion 4c to which an output transformer can be connected is provided on the proximal end side of the holder portion 4. Therefore, the heating coil 1 can be easily electrically and mechanically connected to the output terminal of the output transformer. For example, the shaft hole Wa of the bolt W that cannot move the flange in the turbine chamber is heated. The coil 1 and the output transformer can be arranged in the vicinity of each bolt W to perform induction heating, and the heating coil 1 excellent in usability can be obtained.

  Moreover, the following effects can be acquired with the structure of the coil part 2 of the heating coil 1 of the said embodiment. That is, in a state where the coil portion 2 is inserted and arranged in the shaft hole Wa of the bolt W, a high frequency current is supplied to the coil conductor 2a from the transistor inverter, and from the cooling water supply device in the gap between the coil cover 2b and the coil conductor 2a. Since the cooling water is supplied to the inner surface of the bolt hole W and the inner surface of the coil hole 2 is induction-heated, the entire outer peripheral surface of the coil conductor 2a and the inner surface of the gap can be cooled with the cooling water, thereby effectively generating heat when the coil conductor 2a is energized. And the heating efficiency can be increased.

  At the same time, since the outer diameter of the coil support portion 3 does not need to be increased as in the conventional example due to the configuration of the new cooling water flow path, the coil support portion 3 can be reduced in size so that the heating coil 1 can be transported. It can be installed easily, the range of use of the heating coil 1 can be expanded, and it can be easily used for induction heating of the shaft holes Wa of the bolts W in various installation states. It becomes possible to improve.

  Further, if the coil conductor 2a is formed of a crushed copper pipe obtained by flattening a round (circular) copper pipe, or a rectangular copper pipe having a rectangular cross section, the round copper pipe may be crushed and wound. By winding a rectangular (flat shape) square copper pipe, the coiled conductor 2a can be easily formed, and an increase in the cost of the heating coil 1 can be suppressed. Further, if a faithful conductor such as a thin copper plate is used as the coil conductor 2a, the heating efficiency can be further improved, and the heating coil 1 having excellent usability can be obtained. .

  Further, the coil conductor 2a is electrically and mechanically connected to the proximal end side of the copper pipes 2c and 2d, and the distal end of the copper pipe 2d disposed at the axial center position of the coil conductor 2a on the distal end side. Is electrically and mechanically connected to form a cooling water flow path in both copper pipes 2c and 2d, so that both ends of the coil conductor 2a are electrically connected to the tip of the copper pipes 2c and 2d. While being able to support mechanically stably, cooling water can be distribute | circulated favorably through the copper pipes 2c and 2d, and the heating state stable to the heating coil 1 can be obtained.

  Furthermore, the connection part of the copper pipes 2c, 2d and the coil conductor 2a is provided with a communication hole that communicates the internal space of each copper pipe 2c, 2d and the gap between the coil conductors 2a, so that the copper pipes 2c, 2d and coil The cooling water can be circulated between the conductors 2a, and the cooling water can be supplied and circulated more efficiently in the coil cover 2b, thereby further enhancing the cooling effect of the coil conductor 2a.

  In addition, since the cooling water from the cooling water supply device can be supplied to the gap between the coil conductor 2a and / or the internal space of the coil cover 2b, the cooling water can be supplied into the coil cover 2b in two systems, A cooling system can be set according to the form of the bolt W, and the cooling effect of the coil conductor 2a can be further enhanced. At this time, if the cooling water supply to the gap of the coil conductor 2a and the coil cover 2b is controlled based on the temperature of the cooling water in the coil cover 2b, the cooling state of the coil conductor 2a is adjusted. Cooling under optimum conditions is possible.

  5 to 7 show a second embodiment of the induction heating coil according to the present invention, which is a heating coil for induction heating the outer surface (outer diameter surface) of the object to be heated. This will be described below. The induction heating coil 21 (referred to as a heating coil 21) includes a coil portion 22 having a predetermined outer diameter and a predetermined effective length, a double cylindrical coil cover 23 covering the outer peripheral side of the coil portion 22, and the coil cover 23. The electrode cover 24 provided on the inside, the cooling water supply unit 25, the radiation temperature sensor 26, and the like are provided.

  As shown in FIGS. 6 and 7, the coil portion 22 includes a coil conductor 22a obtained by winding a copper plate having a predetermined plate thickness (for example, about 1 to 5 mm) at a predetermined pitch along the axial direction a predetermined number of times. . At this time, the coil conductor 22a extends to a substantially central position in the axial direction, is bent outward by approximately 90 degrees from the position, and is linearly drawn out in the outer peripheral direction. A lead portion 22b is formed, and this lead portion 22b is supported by the electrode cover 24 as described later.

  The coil cover 23 includes an inner cover 23a, an outer cover 23b, and a pair of side covers 23c and 23d on both sides in the axial direction, each formed of an insulating material. The inner cover 23a is formed in a cylindrical shape with a relatively thin plate thickness, and the outer cover 23b is formed in a cylindrical shape with a plate thickness larger than that of the inner cover 23a, and the center of the outer peripheral surface in the axial (longitudinal) direction. In the position, an electrode mounting hole for connecting the electrode cover 24 in communication with the inside and the outside is formed.

  Further, the pair of side covers 23c and 23d are formed in a circular shape with symmetrical plates having a predetermined thickness, and an object to be heated (not shown) is inserted and arranged at the center position thereof. An opening is formed, and a step-shaped concave portion with which both ends of the inner cover 23a abut is formed in an annular shape on the inner surface portion of the opening. O-rings (O-rings) are fitted on the contact surfaces of the both side surface covers 23c and 23d and both ends of the inner cover 23a.

  In addition, stepped recesses that contact both ends of the outer cover 23b are formed in an annular shape on the inner surfaces of the outer peripheral edges of the pair of side covers 23c, 23d, and the outer side covers 23c, 23d in contact with the outer sides Both ends of the cover 23b are fixed with bolts, for example, at eight locations in the circumferential direction. O-rings are also fitted to the contact surfaces of both end portions of both side covers 23c, 23d and the outer cover 23b.

  As shown in FIGS. 5 and 7, the electrode cover 24 is formed in a bottomed cylindrical shape that is open on the outer cover 23b side and closed on the opposite outer cover 23b side with a bottom wall 24a, and functions as a pair of electrodes 24b. 24c and a coil clamp 24d. The pair of electrodes 24b and 24c pass through a pair of through holes provided in the bottom wall 24a of the electrode cover 24 and project outside the electrode cover 24 by predetermined dimensions, respectively, and within the electrode cover 24, the coil portion 22 It is electrically and mechanically connected to the leading end of the lead-out portion 22b by a crimping terminal or the like.

  The electrode cover 24 has a flange provided on the opening side of the electrode cover 24 in contact with a stepped recess provided in the electrode mounting hole of the outer cover 23b. In this contact state, the flange and the outer cover 23b are in contact with each other. It is fixed by a plurality of bolts. Further, an O-ring is fitted between the peripheral surface on the opening side of the electrode cover 24 and the inner peripheral surface of the electrode mounting hole of the outer cover 23b, and the electrodes penetrate through the electrodes 24c and 24d of the bottom wall 24a. An O-ring is also fitted to the opening end of the hole.

  By these O-rings or the like, an internal space 30 as an airtight cooling space is formed around the coil portion 22 of the assembled coil cover 23, and is fitted to the opening end portion of the electrode through hole. The O-ring prevents leakage of the cooling water in the internal space 30 from the inside of the electrode cover 24 along the outer peripheral surfaces of the electrodes 24b and 24c.

  In addition, the pair of electrodes 24b and 24c made of a copper pipe, a copper rod, or the like projecting outside the bottom wall 24a of the electrode cover 24 is attached to the electrode cover 24 by the coil clamp 24d fixed to the outer surface of the bottom wall 24a of the electrode cover 24. It is supported. The pair of electrodes 24b and 24c are electrically connected to the output terminal of the transistor inverter via, for example, a flexible cable (not shown) or an output transformer arranged as necessary. Yes. As a result, the coil portion 22 is accommodated (incorporated) in the internal space 30 of the coil cover 23 constituted by the inner cover 23a, the outer cover 23b, and both side surface covers 23c and 23d.

  The cooling water supply unit 25 includes, for example, a total of four hose joints 25 a to 25 d provided in a state of being opposed to the both side covers 23 c and 23 d of the coil cover 23. The hose joints 25a to 25d are respectively attached to the attachment holes of the side surface covers 23c and 23d at positions corresponding to the inner space 30 of the coil cover 3, and the joint portions are the outer surfaces of the side surface covers 23c and 23d. Projected to the side. Each of the hose joints 25a to 25d is connected to a cooling tank or the like of a cooling water supplier provided alongside the transistor inverter via a hose or the like (not shown).

  Similarly to the radiation temperature sensor 6, the radiation temperature sensor 16 includes a probe 26 a and a control unit 26 b, and is arranged on the outer circumferential surface at a substantially central position in the axial direction (longitudinal direction) of the coil cover 23. The electrode cover 24 is disposed at an angle of 90 degrees. At this time, a recess 32 shown in FIG. 5 is formed on the outer peripheral surface of the coil cover 23, and the radiation temperature sensor 26 is supported by the recess 32 via a sensor support plate 33.

  Further, the probe 26a of the radiation temperature sensor 26 is arranged in a penetrating manner in the internal space 30 of the coil cover 23, and the tip of the probe 26a is exposed in an airtight state in the heating space 31 from an opening provided in the inner cover 23a. Has been. Thereby, for example, the emitted light from the substantially central portion in the axial direction of the heated object penetratingly disposed in the heating space 31 is received by the probe 26a and measured by temperature control by the control unit 26b on the outer surface side of the outer case 23b. The

  This heating coil 21 is used as follows. That is, a terminal plate made of, for example, a copper plate is fixed to the pair of electrodes 24b and 24c of the heating coil 21, and an output terminal or the like of an output transformer in which this terminal plate is connected to the output terminal of the transistor inverter is connected. The Further, the hose joints 25a to 2d of the heating coil 21 are connected to the cooling water feeder by a hose or the like.

  At this time, one pair of upper and lower hose joints 25a and 25b provided on the side cover 23c and the side cover 23d of the heating coil 21 are used for supplying cooling water (water supply) and provided on the side cover 23d and the side cover 23d. The other pair of upper and lower hose joints 25c and 25d is used for discharging (draining) the cooling water. Thereby, a relatively gentle flow of the cooling water is generated in the internal space 30 having a large volume, and the outer peripheral surface of the coil conductor 22a is cooled by the flow of the cooling water.

  When a high-frequency current is supplied from the transistor inverter to the electrodes 24b and 24c via the output transformer or the like in the cooled state of the coil conductor 22a, for example, a cylindrical shape disposed in the heating space 31 of the heating coil 21 An eddy current is induced on the outer peripheral surface of the object to be heated, and the object to be heated is induction heated. At the time of this induction heating, the coil conductor 22a of the coil portion 22 is close to the inner cover 23a, and the outer peripheral surface of the object to be heated can be efficiently irradiated with magnetic lines of force radiated from the front and back surfaces of the coil conductor 22a. Since the heat generation of 22a itself is effectively suppressed, the induction heating efficiency of the object to be heated is sufficiently increased.

  For induction heating by the heating coil 21, the heating temperature of the outer surface of the object to be heated is sequentially measured by the radiation temperature sensor 26, and the signal is input to the control unit of the high frequency induction heating device. Then, when the measured temperature reaches a preset temperature preset in the control unit, for example, the operation of the transistor inverter is stopped. Thereby, the outer surface of the article to be heated is heated at a predetermined temperature.

  At this time, in the case of the heating coil 21, during the induction heating, the radiation temperature sensor 26 is integrally disposed on the outer surface of the coil cover 23 of the heating coil 21 via the sensor support portion 33, and from the object to be heated. Synchrotron radiation can be received by the tip of the probe 26a exposed in the heating space 31, and the temperature of the axial center portion of the outer peripheral surface of the object to be heated can be measured successively and accurately, and the outer surface of the object to be heated Can be heated at a desired temperature. Needless to say, the probe 26a of the radiation temperature sensor 26 is disposed without interfering with the coil conductor 22a or the like in the coil cover 23.

  According to the heating coil 21 of this embodiment, the inner side, the outer side, and both side surfaces of the coil portion 22 around which the coil conductor 22a is wound are covered with airtightness, and the heating target can be arranged on the inner peripheral side. Cooling water is circulated and supplied into the internal space 30 of the coil cover 23 having the space 31, and the coil conductor 22 a is cooled with the cooling water, and is disposed at a predetermined position in the axial direction of the coil cover 23. Since the probe 26a that receives the radiation light from the inserted object to be heated is provided with the radiation temperature sensor 26 directed to the outer peripheral surface of the object to be heated, for example, the coil part 22 is placed in the cooling water flowing through the coil cover 23. Even if the heating coil 21 is cooled in an immersion state, the probe 26a of the radiation temperature sensor 26 accurately measures the heating temperature at a predetermined position on the outer surface of the object to be heated during induction heating in the heated state. Te, it is possible to easily obtain a highly accurate heating state to be heated.

  Further, the coil conductor 22a of the coil portion 22 can be formed of a plate-like conductor or the like, and these are configured so as to be cooled in the cooling water supplied into the coil cover 23, so that the coil conductor 22a can be effectively The heating coil 21 can be cooled and the heating efficiency of the heating coil 21 can be sufficiently increased, and the heating coil 21 excellent in usability can be obtained. Further, in this heating coil 21 as well, the coil conductor 22a can be cooled in the state of being immersed in cooling water, or a plate or a flat pipe can be used as the coil conductor 22a. Therefore, the heating coil 21 is substantially the same as the heating coil 1 of the first embodiment. The effect of this can be obtained.

  In addition, the structure of each part in the said each embodiment is an example, Comprising: For example, the number of turns of the coil conductors 2a and 22a is not constant (uniform) in the axial direction. The number of turns in the axial direction is varied, for example, rough, and the inner surface in the axial direction of the shaft hole can be heated more uniformly. For example, an appropriate conductor having no internal gap may be used, and equivalent changes can be made without departing from the gist of each invention according to the present invention.

  The present invention is not limited to application to metal bolts for tightening flanges in a steam turbine chamber, and it is necessary to induction-heat all objects to be heated, or inner and outer surfaces that require induction heating in the shaft hole at the center position. Available for all metal products.

  DESCRIPTION OF SYMBOLS 1 ... Induction heating coil, 2 ... Coil part, 2a ... Coil conductor, 2b ... Coil cover, 2c, 2d ... Copper pipe, 3 ... Coil support part, 3a ... Coil fixing nut, 3b ... Coil fixing plate, 3c ... Sensor support plate, 3d ... Coil clamp, 4 ... Holder part, 4a ... Copper plate, 4c ... Terminal part, 4d ... -Cooling pipe, 4e ... hose joint, 6 ... radiation temperature sensor, 6a ... probe, 6b ... control part, 21 ... induction heating coil, 22 ... coil part, 22a ... Coil conductor, 23 ... Coil cover, 23a ... Inner cover, 23b ... Outer cover, 23c, 23d ... Side cover, 24 ... Electrode cover, 24a, 24b ... Electrode, 25 ... Cooling water supply units, 25a to 25d -Hose joint, 26 ... Radiation temperature sensor, 26a ... Probe, 26b ... Control unit, 30 ... Internal space, 31 ... Heating space, 33 ... Sensor support plate, W ...・ Metal bolt, Wa ... shaft hole,

Claims (5)

  A coil part having a coil conductor wound with a predetermined gap and a predetermined number of turns and a bottomed cylindrical coil cover covering the outer peripheral side of the coil conductor, and supporting the open base end side of the coil part A coil support part having a cooling water supply part capable of supplying cooling water in the coil cover, and a flow tube which is integrally disposed on the coil support part and capable of receiving radiated light from the object to be heated is the object to be heated. An induction heating coil comprising: a radiation temperature sensor oriented toward the inner diameter surface of the coil.   The coil support portion is connected and connected to a holder portion made of a pair of copper plates that are press-fixed via an insulating plate, and a cooling pipe capable of supplying cooling water to the cooling water supply portion is fixed to the outer surface of the holder portion. The induction heating coil according to claim 1, wherein a connection portion to which a transformer can be connected is provided on the proximal end side of the holder portion.   A coil cover having a coil portion in which a predetermined number of coil conductors are wound, and a heating space in which an inner side, an outer side, and both side surfaces of the coil portion are hermetically sealed and an object to be heated can be inserted and arranged on the inner peripheral side. A cooling water supply unit that can circulate and supply cooling water into the internal space of the coil cover, and an object to be heated that is disposed at a predetermined position in the axial direction of the coil cover and inserted into the heating space. An induction heating coil, comprising: a probe capable of receiving radiation light from a radiation temperature sensor directed toward the outer peripheral surface of the object to be heated.   The induction heating coil according to any one of claims 1 to 3, wherein the radiation temperature sensor is arranged so as to be movable and adjustable in the coil conductor direction.   The coil conductor is formed by winding a flat copper pipe or a solid conductor, and these coil conductors are configured so as to be cooled in an immersion state in cooling water supplied from the cooling water supply unit into the coil cover. The induction heating coil according to claim 1, wherein:

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