JP2005222745A - Heating device of metal tube body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form each receiving roller with an inexpensive metal material easy to purchase and to compose a heating device with a structure capable of preventing spark between workpiece receiving rollers for providing long-term durability, in a heating device of a metal tube body for induction-heating the total length of a workpiece while rotatably supporting it with two receiving rollers. <P>SOLUTION: This metal tube body heating device 40 is equipped with: the receiving rollers 50 and 60 for mounting the metal tube body 10 in a manner capable of horizontally and rotatably transmitting it; roller driving devices 25-26 for rotatably driving them by pivoting them; and induction heating devices 21-22 for induction-heating the total length of the metal tube body 10. The rollers 50 and 60 are composed of: metallic core members 51 and 61; a plurality of metallic short sleeves 52 and 62 each having an axially split form; and spacers 53 and 63 serving as mutual insulation thereof. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a heating device for a metal cylinder that is heated to a high temperature while rotating the shaft of a metal cylinder, and more particularly to a heating device for a metal cylinder that performs heating by induction heating.
Such a heating device for a metal cylinder can apply centrifugal force to the contents in the metal cylinder while heating the metal cylinder. For example, a self-fluxing alloy coating is applied to the inner peripheral surface of the metal cylinder. It is suitable for.

  When applying the fusion coating of the self-fluxing alloy to the inner surface of the metal cylinder, the self-fluxing alloy powder is charged into the metal cylinder, and the metal cylinder is rotated around the axis while rotating the metal cylinder. However, there is known a so-called one-shot construction method and a metal cylinder heating apparatus in which powder in a metal cylinder is heated and melted at a time (see, for example, Patent Document 1). This device includes a cylinder support rotating device that rotates a metal cylinder at a high speed, and an induction heating device that heats the rotating metal cylinder in one shot. Employs a face-fired coil that induction-heats a small section in the circumferential direction of the metal cylinder over the entire length of the metal cylinder.

  A saddle-shaped induction coil is also frequently used as an inductor for induction heating the entire length of the metal cylinder, and the main part of the metal cylinder heating apparatus 20 equipped with such an inductor 22 is shown in FIG. It was. The inductor 22 includes two portions that run in the axial direction along the metal cylinder 10 over almost the entire length of the metal cylinder 10. Further, the cylinder support rotating device in the metal cylinder heating device 20 has the two receiving rollers 23 and 24 shown in the figure as a main part, and these rollers 23 and 24 are supported by a roller driving device (not shown). Then, it is designed to rotate.

  The receiving rollers 23 and 24 are both installed in parallel in a horizontal state and at an appropriate distance so that the metal cylinder 10 to be heated can be mounted, and the metal cylinder 10 is mounted with the axial direction aligned. Then, the metal cylinder 10 is supported horizontally and rotatably. When one or both of the receiving rollers 23 and 24 are rotationally driven, the metal cylinder 10 is axially rotated at a desired speed by contact rolling of the outer peripheral surfaces.

When high-frequency energization is performed on the inductor 22 while the metal cylinder 10 is mounted on the metal cylinder heating device 20 and the shaft is rotated, the outer circumferential surface of the metal cylinder 10 (see FIG. 9B) is almost the same. A saddle-shaped primary induced current 11 is induced and the electric circuit portion is heated. However, since the metal cylinder 10 is rotating at a high speed, the metal cylinder 10 is heated almost uniformly around the entire circumference. In the case of self-fluxing alloy coating, the metal cylinder body has a speed at which the centrifugal force (acceleration) is 30 m / s ² (≒ 3G, where G is gravitational acceleration) or more in order to make the powder layer of the self-fluxing alloy uniform. 10 is rotated, and the metal cylinder 10 is heated to a high temperature at which the self-fluxing alloy is fused.

  Conventionally, rollers made of non-magnetic stainless steel (austenitic steel) are employed as the receiving rollers 23 and 24. In the case of induction heating, if possible, we would like to adopt a roller made of an electrical insulator such as alumina. However, in the category of insulating materials and non-good conductors, an appropriate material that can withstand contact rolling at high speed for a long time. Because it is not found. Alumina and the like are difficult to procure and process a member having a desired dimension, are expensive, and require a long time for production. Stainless steel, on the other hand, has high toughness and is resistant to cracking and peeling, so it can withstand severe long-term contact rolling, and it is easy to procure and process parts with the desired dimensions, and is inexpensive and can be replenished in a short period It is.

JP 2003-193262 A

  However, when the receiving rollers 23 and 24 are made of stainless steel, since the stainless steel is a good electrical conductor, the secondary induction current 12 is also induced in the receiving rollers 23 and 24 when high-frequency current is applied (see FIG. 9C). Although the secondary induced current 12 flows through the receiving rollers 23 and 24 via both ends of the metal cylinder 10 and heats the receiving rollers 23 and 24, it indirectly serves to heat the metal cylinder 10. , Secondary and secondary. When the receiving rollers 23 and 24 and the metal cylinder 10 are shaken with the rotation of the shaft and the contact between the rollers 23 and 24 and the metal cylinder 10 is broken, the secondary induced current 12 is continually recirculated. When the induced electromotive force is strong, for example, sparks due to discharge are generated at the four rolling surface end portions 13, 14, 15, 16 at both ends of the metal cylinder 10.

When spark is generated, spark marks are formed on the outer peripheral surfaces of the receiving rollers 23 and 24 and the metal cylinder 10. And once a spark mark is generated, the contact failure is constant, and a lot of sparks are generated. If it does so, the quality of the metal cylinder 10 will be impaired and the lifetime of the receiving rollers 23 and 24 will become short.
Therefore, in the conventional receiving rollers 23 and 24, the advantage of long-term durability such as toughness of stainless steel is not fully utilized, and only the advantage of being inexpensive and easy to replenish for a short period is utilized.

  Therefore, in order to utilize the long-term resistance of stainless steel, in order to provide electrical insulation to the stainless steel receiving rollers 23 and 24, an insulating coating is formed on the outer peripheral surface by alumina spraying, and the receiving roller 33 with insulating coating is provided. , 34 equipped with a metal cylinder heating device 30 (see FIG. 10A). In this case, the primary induced current 11 flowing only through the metal cylinder 10 is the same as the conventional one (see FIG. 9B), but the secondary induced current 12 induced in the receiving rollers 33 and 34 is (FIG. 10B). Since the primary induced current metal cylinder 10 and the receiving rollers 33 and 34 are electrically insulated, they circulate in the receiving rollers 33 and 34 and remain in the respective rollers. And sparking is prevented.

  However, since it rolls at a high speed in a heating environment, the insulation coating is likely to crack and peel off, and as it grows, the electrical insulation eventually breaks and discharge occurs, and when a spark occurs, the crack spreads and the like spreads. Accelerates wear and tear. Then, as in the case where there is no insulation coating, sparks frequently occur at the rolling surface end portions 13, 14, 15, 16 and the like (see FIG. 10C), and the life of the receiving rollers 33, 34 is exhausted. For this reason, the life extension beyond the cost increase of insulation coating construction is not realized.

  Therefore, in order to make full use of the advantages for rollers such as stainless steel, that is, to make full use of the advantages of long-term durability in addition to the advantages of cheap and short-term replenishment, it is made of metal materials. When providing electrical insulation to the receiving roller, it is a technical problem to further devise the concrete structure and the way of adding insulating means.

  The metal cylinder heating device of the present invention (initial claim 1) has been devised in order to solve such problems, and has a two-row receiving structure that supports the metal cylinder to be heated while rotating it. In a metal cylinder heating device comprising a roller, a roller driving device that rotationally drives the receiving roller, and an induction heating device that induction-heats the metal cylinder at the same time, the receiving roller is a metal core member The sleeve is divided into a plurality of short sleeves, and the sleeve is electrically insulated from the core member, and a gap is provided between the short sleeves. It is said that it is fitted in a form.

  A metal cylinder heating apparatus according to the present invention (initial claim 2) is the metal cylinder heating apparatus according to the above-mentioned initial claim 1, and further, the plurality of short sleeves are electrically connected to the core member. The means for insulating is an electrically insulating coating applied to the outer peripheral surface of the core member or the inner peripheral surface of the short sleeve, and the short sleeve is tightly fitted to the core member via the coating. It is that.

  Further, the metal cylinder heating device according to the present invention (initial claim 3) is the metal cylinder heating device according to the above-mentioned initial claim 1, and further, the short sleeve is provided on the inner peripheral surface of the short sleeve. A key groove extending over the entire length is provided, and a key member is planted on the outer peripheral surface of the core member, and the short sleeve projects the key member into the key groove to form the core member. Further, the gap between the short sleeves is maintained by an electrically insulating spacer that is fixed in the circumferential direction and is key-engaged with the key groove of the short sleeve and disposed between the short sleeves. That's it.

A metal cylinder heating device according to the present invention (initial claim 4) is the metal cylinder heating device according to the above-mentioned initial claim 3, and further, the short sleeve is detached at the end of the core member. It is said that a stopper for preventing this is disposed.
Moreover, the metal cylinder heating device (initial claim 5) of the present invention is the metal cylinder heating device according to the initial claim 1, and the sleeve is made of a nonmagnetic metal such as stainless steel. That's it.

Moreover, the metal cylinder heating device of the present invention (initial claim 6) is the metal cylinder heating device according to the above-mentioned initial claims 1 to 5, and further, the roller driving device is insulated from the ground. It has been said.
The metal cylinder heating device according to the present invention (initial claim 7) is the metal cylinder heating device according to the above-mentioned initial claim 6, further comprising an end portion of the core member at the roller driving device. Both end bearing portions that pivotally support and an intermediate bearing portion that pivotally supports the intermediate portion of the core member are provided.

  In such a metal cylinder heating apparatus of the present invention (initial claim 1), the metal cylinder is horizontally supported by a cylinder support rotating device including a receiving roller and a roller driving device, Further, the shaft is rotated. Moreover, it heats over the full length with an induction heating apparatus. Thereby, centrifugal force can be made to act on a metal cylinder, heating a metal cylinder once, for example, self-fluxing alloy coating can be appropriately given to the inner peripheral surface of a metal cylinder.

  Moreover, the receiving roller is divided in both the radial direction and the axial direction to insulate the divided bodies from each other. That is, the receiving roller is divided into a core member on the roller driving device side and a sleeve on the metal cylinder side in the radial direction. At the same time, the sleeve is further divided into several short sleeves in the axial direction, and each short sleeve is mutually insulated, so that the secondary induced current induced in the receiving roller is cut in units of short sleeves. It will be. And since the induced electromotive force that works when the contact between the metal cylinder and the receiving roller is broken with rotation is also divided and weakened individually, it becomes difficult for discharge to occur and even if it occurs, it disappears Therefore, the frequency of unwanted sparks is drastically reduced.

Therefore, even if the sleeve is made of a metal material, there is no inconvenience due to electric discharge, and there is no need to dispose an insulating member that embodies the insulating means at the contact rolling site. If the short sleeve is made of a metal material that is easy to select a member having the advantages of low cost, easy short-term replenishment, and long-term durability, the life of the receiving roller is completed.
Therefore, according to the present invention, it is possible to realize a metal cylinder heating apparatus that is inexpensive and suitable for long-term use.

  In the metal cylinder heating device of the present invention (initial claim 2), an insulating coating is formed on the outer peripheral surface of the core member or the inner peripheral surface of the short sleeve to electrically insulate the short sleeve from the core member. In addition, the short sleeve is tightly fitted to the core member through the above-described covering, so that the coaxial arrangement of the short sleeve with respect to the core member can be easily and reliably realized, and the short sleeve outer surface after fitting can be rotated at high speed. The required high degree of concentricity, roundness and coaxiality are ensured, and the original roller function is easily secured. In addition, in this case, since the insulating coating of the core member is fitted around the sleeve and does not roll in contact with the metal cylinder, the insulating coating is also maintained for a long period of time. In the above-described tight fitting, the short sleeve can be easily fitted without damaging the insulation coating of the core member by externally fitting the sleeve to the core member by shrink fitting. In addition, since the sleeve is divided into short sleeves, shrink fitting of the sleeve is easier, and material costs for repair and replacement can be kept low.

  Further, in the metal cylinder heating device of the present invention (initial claim 3), an insulating spacer is interposed between the ends of the short sleeve, so that the short sleeve is caused by, for example, abnormal temperature rise. Even when the sleeve is loosened and can move in the axial direction of the core member, the electrical insulation between the short sleeves is reliably maintained. Also, since the key member implanted on the outer peripheral surface of the core member is inserted into the key groove on the inner peripheral surface of the sleeve, the sleeve loosens due to, for example, abnormal temperature rise, and the circumferential friction with the core member Even when the force is weakened or lost, the core member is reliably prevented from spinning around. In addition, since the key groove extends to both ends of the sleeve, the key member does not hinder the shrink fitting of the sleeve.

  Furthermore, since the metal cylinder heating device of the present invention (initial claim 4) is provided with stoppers for preventing the short sleeve from dropping off at both end portions of the core member, the abnormal temperature rise is extremely low. Even if it reaches the end of the receiving roller, the above-mentioned drop-off is suppressed even by the short sleeve, which is the initial movement, from protruding from the end of the core member. It has become a device unrelated to the situation.

  In the metal cylinder heating device of the present invention (initial claim 5), since the short sleeve is made of a non-magnetic (non-ferromagnetic) metal, the induced current induced in the short sleeve during induction heating is reduced. Penetration depth (index of concentration of induced current and heat input derived from it in the vicinity of the magnetic flux input surface / concentration increases as the penetration depth decreases) is several tens to several hundreds times the penetration depth in ferromagnetic metals. As a result, the amount of heat input within the thickness range of the short sleeve (that is, the heat input density in the short sleeve) can be reduced, and the temperature rise of the short sleeve can be suppressed. Even when the short sleeve is made of a ferromagnetic metal such as carbon steel, it becomes non-magnetic at a temperature exceeding the magnetic transformation temperature, so the suppression of heat input is limited to the middle stage of the heating process of the metal cylinder. However, the temperature difference up to this magnetic transformation temperature greatly contributes to the suppression of the ultimate temperature in the heating process. As a result, for example, the thickness of the short sleeve can be freely selected without consideration of increasing the wall thickness in order to keep the temperature reached within the allowable limits, as in the case of a ferromagnetic metal. This is a useful measure for reducing costs.

  Further, in the metal cylinder heating device of the present invention (initial claim 6), due to the ground insulation of the roller driving device, it is caused by the induced current (so-called tertiary induced current) induced in the core member. Even the discharge to be suppressed is suppressed.

  Moreover, in the metal cylinder heating device of the present invention (initial claim 7), not only the both ends of the core member are pivotally supported while being insulated against the ground, but also the intermediate portion of the core member is pivotally supported while being insulated from the ground. By doing so, the vibration during rotation of the receiving roller is suppressed to be small. For example, even when the receiving roller is long or when the receiving roller is rotated at high speed, the impact at the contact rolling portion between the metal cylinder and the sleeve is small. In addition, it is difficult to generate or grow a discharge at a contact rolling site.

  Moreover, by attaching a water cooling cover to the intermediate bearing portion, the intermediate bearing portion is protected from the radiant heat generated by the receiving roller and the metal cylinder.

  A configuration of an embodiment of a metal cylinder heating apparatus (hereinafter referred to as a metal cylinder heating apparatus) according to the present invention will be described with reference to the drawings. Fig.1 (a) is a perspective view which shows the whole structure of a metal cylinder heating apparatus, and FIG. 2 is a top view of two receiving rollers. 3 shows the external structure of each part of the receiving roller, (a) is a perspective view of the core member, (b) is a perspective view of the short sleeve, (c) is a perspective view of the insulating spacer, and (d) is a perspective view of the insulating spacer. It is an expanded view of a receiving roller. Further, FIG. 4 shows the internal structure of each part of the receiving roller, (a) is a front view of the receiving roller, (b) is an AA sectional arrow view, (c) is a BB sectional arrow view, and (d) is its sectional view. (E) is a C-part enlarged front view, (f) is a sectional view thereof, and (g) is a partially enlarged view thereof.

  In these drawings, for simplification and the like, a support mechanism for the inductor 22, a fastener such as a base, a frame, and a bolt, a coupling tool such as a hinge, an electric circuit such as a motor driver, and an electronic circuit such as a controller. Etc. are not shown in the figure, and those necessary for explaining the invention and related ones are mainly shown. In addition, since the same reference numerals are given to the same components as those in the prior art in the illustration, the repeated description will be omitted, and the following description will focus on differences from the prior art.

  The metal cylinder heating device 40 of this embodiment is different from the metal cylinder heating devices 20 and 30 described above in that the receiving rollers 23 and 24 and the receiving rollers 33 and 34 become receiving rollers 50 and 60. is there. FIG. 1 (a) also shows one high-frequency power source 21, four end bearings 25, and a single motor 26, which are not shown in FIGS. It was also equipped in the cylinder heating device 20 (see also Patent Document 1).

  In other words, the metal cylinder heating device 40 includes the receiving rollers 23 and 24 that can support the horizontal and rotational transmission of the metal cylinder 10 to be heated when the two metal cylinders 10 to be heated are mounted in parallel. A metal cylinder heating device 20 including roller driving devices 25 to 26 that rotatably support the receiving rollers 23 and 24 and induction heating devices 21 to 22 that induction heat the entire length of the metal cylinder 10 is provided. As a basis, it has been improved by replacing the receiving rollers 23 and 24 with the receiving rollers 50 and 60.

  As described above, the cylindrical body supporting and rotating device that rotates the metal cylindrical body 10 at a speed suitable for the self-fluxing alloy coating construction includes the receiving rollers 50 and 60 and the roller driving devices 25 to 26. However, a specific example of roller driving devices 25 to 26 including four end bearing portions 25 and one electric motor 26 is shown (see FIG. 1A). The both end bearing portions 25 are arranged so as to pivotally support the respective end portions of the receiving rollers 50 and 60, and the electric motor 26 rotationally drives the receiving roller 50 through one end bearing portion 25 of them. . The high-frequency power source 21 supplies an appropriate high frequency to the inductor 22 formed of a saddle-shaped induction coil according to an appropriate energization schedule.

  The receiving rollers 50 and 60 (see FIG. 2) have the same structure and shape, and are arranged in parallel at an axial distance narrower than the diameter of the metal cylinder 10, but at this time, a gap between the short sleeves 52 is received. Since the rollers are installed in a state in which the axial direction is reversed so as to be alternated between the rollers, the reference numeral “50” is attached to one and “60” is attached to the other, so that they can be distinguished. Further, each member of the receiving roller 50 is denoted by a symbol “50 units”, and a corresponding member of the receiving roller 60 is denoted by a symbol “60 units” which is increased by “10”. Hereinafter, although the structure of the receiving roller 50 will be described in detail, the structure of the receiving roller 60 is the same. The receiving roller 50 (see FIGS. 2 and 3) includes a single core member 51 that is rotatably supported by the bearings 25 at both ends, and twelve that are fitted in the core member 51 in the axial direction. Each of the short sleeves 52 includes twenty-two spacers 54 that restrict the positions of the short sleeves 52 so as not to conduct each other, and eight stoppers 55.

  The core member 51 (see FIG. 3 (a)) is a shaft made of a stainless steel rod that is a good conductor but has excellent toughness and is inexpensive. Both ends have a small diameter suitable for the both-end bearing portion 25, but the other ends are finished in a cylindrical shape with the same diameter, and a key member 51a is implanted on the outer peripheral surface thereof. The twenty-four key members 51a are divided on both sides of the axis, and are all arranged in parallel with the axis. In addition, an insulating coating is formed on the outer peripheral surface of the core member 51 by alumina spraying or the like for electrical insulation from the short sleeve 52. Since the key member 51a is also made of stainless steel, it is insulated and coated together or separately. Further, screw holes for attaching the stopper 55 are formed at both ends of the core member 51, and if it is necessary to reduce the weight, a hollow 51b is formed in the core portion (see FIG. 4B).

  The short sleeve 52 (see FIG. 3B) is formed by cutting a stainless steel cylindrical body shorter than the core member 51 and engraving a key groove 52a on the inner peripheral surface thereof. Two key grooves 52 a are formed, both of which extend over the entire length including both ends of the short sleeve 52. The width and depth of the key groove 52a are constant, and the protruding portion of the key member 51a described above can be fitted. The short sleeve 52 is made of a solid stainless steel material for shrink fitting, that is, heated and expanded and fitted to the core member 51, and has an inner diameter slightly smaller than the outer diameter of the core member 51.

  The insulating spacer 54 (see FIG. 3C) is a small piece of stainless steel with a convex end surface, and one held portion 54b is inserted into the key groove 52a from the end surface of one of the short sleeves 52, and the short sleeve 52 is inserted. When the other held portion 54 b is inserted into the key groove 52 a from the end surface of another short sleeve 52 adjacent to the short sleeve 52, the short sleeve separating portion 54 a protrudes between the opposed end surfaces of both short sleeves 52, and adjacent short sleeves 52. The end gap 53 between them is maintained above a certain level. The short sleeve separating portion 54a and the held portion 54b have at least a surface that may come into contact with the short sleeve 52, and are coated with alumina spraying or the like for electrical insulation, and have the necessary electrical insulation for the spacer. Yes. The stopper 55 is also covered with insulation.

  These are combined (see FIG. 2) to form the receiving roller 50 (see FIG. 4). Specifically, the short sleeves 52 are fitted into the core member 51 one by one by shrink fitting, and at that time, the protruding portion of the key member 51a is inserted into the key groove 52a. Further, when the next short sleeve 52 is fitted after the one short sleeve 52 is fitted, two spacers 54 are interposed between the end portions thereof. The spacer 54 is a state in which the held portion 54b is inserted into the key groove 52a of the short sleeve 52 and is placed between the short sleeve 52 and the core member 51, and the short sleeve separating portion 54a protrudes from the key groove 52a. Is inserted between the ends of the short sleeves 52 on both sides.

  About the metal cylinder heating apparatus 40 of this embodiment, the use aspect and operation | movement are demonstrated referring drawings. FIG. 1B is a perspective view showing a usage state of the metal cylinder heating device 40, and FIG. 1C is a perspective view showing how the secondary induced current 12 induced in the receiving roller 60 flows.

  The usage of the metal cylinder heating device 40 is basically the same as the conventional one. That is, (refer FIG.1 (b)), when heating the metal cylinder 10 using the metal cylinder heating apparatus 40 in order to perform the fusion coating of a self-fluxing alloy on the inner peripheral surface of the metal cylinder 10, First, the metal cylinder 10 is mounted on the receiving rollers 50 and 60, and then the pre-operation corresponding to the application such as charging of the self-fluxing alloy powder is performed, and the inductor 22 is brought closer to the metal cylinder 10 or the inductor 22 Is in a position where induction heating is possible with respect to the metal cylinder 10, and then the electric motor 26 and the high frequency power source 21 are operated.

If it does so, the receiving roller 50 will carry out an axial rotation and the metal cylinder 10 and the receiving roller 60 will also carry out an axial rotation in connection with this. The rotation speed is maintained at a speed at which a desired centrifugal force is generated on the inner peripheral surface of the metal cylinder 10 by control of a controller or the like (not shown). The centrifugal force that is suitable for coating application of the self-fluxing alloy ^{(acceleration), 30m / s 2 (≒} 3G, Note G is gravitational acceleration) or more is desirable, in Patent Document 1 30~100m ^/ s 2 (3~10G ) and, although the scope of 50~100m ^/ s 2 (5~10G) are illustrated, more ^recently, are also frequently used range 200~500m / s 2 (20G~50G).

  Further, high frequency energization is performed on the inductor 22, and a substantially bowl-shaped primary induced current 11 is induced on the outer peripheral surface of the metal cylinder 10 (see FIG. 9B), and the electric circuit portion is heated. Since the metal cylinder 10 is rotating at high speed, the entire circumference of the metal cylinder 10 is heated almost uniformly. In the case of coating the self-fluxing alloy, the metal cylinder 10 is heated to a high temperature at which the self-fluxing alloy is fused. The temperature is about 1000 ° C. or higher as described in Patent Document 1, and the high-frequency energization condition required for the temperature is a low frequency band of about 0.3 kHz to 5 kHz and a power of about 200 kW to 1200 kW. The energizing conditions for extra power are often used, but others are also used.

Furthermore, since most of the receiving rollers 50 and 60 are made of stainless steel, the secondary induction current 12 is also induced in the receiving rollers 50 and 60 when high-frequency current is applied.
However, since the structures of the receiving rollers 50 and 60 are different from those of the conventional receiving rollers 23 and 24, the flow of the secondary induced current 12 in the receiving rollers 50 and 60 is different from the conventional one.

  That is, (see FIG. 1C), in the receiving roller 60, the outer peripheral surface portion, which is the secondary induced current 12 induction site, is divided into twelve short sleeves 62, which are electrically insulated from each other. Therefore, the secondary induced current 12 is also divided corresponding to the short sleeve 62, and each secondary induced current 12 flows through a small closed loop in the corresponding short sleeve 62, so that the source of the secondary induced current 12 is induced. The electromotive force is also divided and distributed. The same applies to the receiving roller 50.

Therefore, when the receiving rollers 50 and 60 and the metal cylinder 10 are shaken as the shaft rotates and the contact between the receiving rollers 50 and 60 and the metal cylinder 10 is broken, an attempt is made to continue the recirculation of the induced current. Even if the induced electromotive force works, the induced electromotive force dispersed in each short sleeve 62 is orders of magnitude weaker than that otherwise, so that the occurrence of sparks is drastically reduced.
Thus, in this metal cylinder heating device 40, since the receiving rollers 50 and 60 are hardly exposed to the spark, the advantages of long-term durability such as toughness of stainless steel are fully enjoyed. Can be used without inconvenience.

When the short sleeves 52 and 62 are damaged after long-term use, the other members can be used continuously by replacing only the short sleeves with new ones. The short sleeve can be easily replaced by shrink fitting as in the assembly of the receiving rollers 50 and 60.
Further, the spacer 54 for securing the end gaps 53 and 63 provided as an insulating means, the insulating coating of the core member 51, the insulating coating of the spacer 54, and the insulating coating of the stopper 55 are the same as the insulating coating of the receiving rollers 33 and 34. Unlike this, it is not exposed to harsh contact rolling, so it also withstands long-term use.

  In addition, not only the metal cylinder 10 but also the receiving roller 50 is heated with the heating of the metal cylinder 10, and the heating acts more strongly on the short sleeve 52 than the core member 51. The tightening force on the member 51 tends to be weakened. If it goes too far and loosens undesirably, the short sleeve 52 can move both in the circumferential direction and in the axial direction of the core member 51. However, even in such a case, in the receiving roller 50, the core member 51 is prevented from spinning by the cooperation of the key member 51a and the key groove 52a, and the spacers 54 are adjacent to each other. The contact short circuit between the short sleeves 52 is prevented, and the stopper 55 prevents the short sleeves 52 from coming off.

  The configuration of another embodiment of the metal cylinder heating device of the present invention will be described with reference to the drawings. FIG. 5 is a perspective view showing the overall structure of the metal cylinder heating device, FIG. 6 is a plan view of two receiving rollers (or a configuration in which four are arranged in two rows), and FIG. It is the front view and side view of an intermediate bearing part. Note that the front view of FIG. 7 shows a state in which the cover is cut vertically and the front portion is removed.

The metal cylinder heating device 70 of this embodiment is different from the metal cylinder heating device 40 described above in that the intermediate bearing portion 72 is added to the roller driving devices 25 to 26 and the roller driving device is insulated from the ground. It is a point.
Insulation to the ground (see FIG. 5) is performed by laying insulating plates 71 on the bottom surfaces of the both end bearing portions 25, the motor 26, and the intermediate bearing portion 72, whereby the induced current induced in the core member of the receiving roller is generated. Since it is prevented from flowing to the installation floor or the like via the roller driving device, even the discharge caused by the flow is suppressed.

  Due to the introduction of the intermediate bearing portion 72 that pivotally supports the intermediate portion of the core member, the receiving roller may be a long one extending between the both end bearing portions 25 on both sides, and the short between the both end bearing portions 25 and the intermediate bearing portion 72. The two receiving rollers 80 and 90 are also made of stainless steel on the stainless steel core members 81 and 91 having an outer peripheral surface coated with an insulating coating, like the receiving rollers 50 and 60. The short sleeves 82 and 92 are shrink-fitted. In the receiving rollers 80 and 90, when the short sleeves 92 are arranged in the axial direction, all of them are not arranged closely but are partially omitted. A water-cooled cover is attached to the intermediate bearing portion 72 in order to shield radiant heat.

  In this case, since the shaft support of the receiving rollers 80 and 90 is made not only by the both end bearing portions 25 at both ends but also by the intermediate intermediate bearing portion 72, even when the receiving rollers 80 and 90 are rotated at high speed, the receiving rollers Since the vibration of 80 and 90 is suppressed to a small level, the impact at the contact rolling portion between the metal cylinder 10 and the short sleeves 82 and 92 can be reduced. Further, since the short sleeves 82 and 92 are divided in the axial direction and insulated from each other, and the roller driving devices 25 to 26 and 72 that pivotally support the core members 81 and 91 are insulated from the ground, the contact rolling part and the like Therefore, the receiving rollers 80 and 90 can withstand long-term use.

  Further, the intermediate bearing portion 72 shields the radiant heat generated by the receiving rollers 80 and 90 and the metal cylinder 10 by the cover exposing portion 74, and in addition to alleviating the heating, the intermediate bearing portion 72 leads to the water passing portion 73 of the cover. Therefore, even if the environment is harsh, an excessive increase in the temperature of the bearing portion can be avoided and it can withstand long-term use.

Thus, in this metal cylinder heating device 70, the receiving rollers 80 and 90 are hardly exposed to the sparks, and the impact due to the contact rolling is not so much received. be able to.
Even in the case of the metal cylinder heating device 70, the advantage based on the replacement of the short sleeve unit, the extension of the life by avoiding the contact rolling of the insulation coating, the prevention of idling with the key member etc. against the abnormal relaxation of the short sleeve, and It is effective to prevent a short circuit with an insulating spacer or the like.

  Prototyping the above-described metal cylinder heating device 40 and metal cylinder heating device 70, the insulation state of the short sleeve, the run-out of the receiving roller when there is no load and when it is loaded, and the number of times used until the occurrence of a spark mark I investigated. For the metal cylinder heating device 70, the temperature of the intermediate bearing 72 was also measured.

The core members 51 and 61 of the receiving rollers 50 and 60 of the metal cylinder heating device 40 are made of JIS / SCM440, have an outer diameter of 120 mm and a length of 1920 mm. The insulating coating is made of alumina and has a thickness of 0. .3 mm and formed by thermal spraying.
The short sleeves 52 and 62 are made of JIS / SUS304, have an outer diameter of 150 mm, an inner diameter of 120 mm, and a length of 155 mm. Note that only one half is placed at one end.

The core members 81 and 91 of the receiving rollers 80 and 90 of the metal cylinder heating device 70 are divided at the intermediate bearing portion 72. One length is 1254 mm and the other length is 950 mm. Is JIS / SCM440 and has an outer diameter of 150 mm. The insulating coating is made of alumina and has a thickness of 0.3 mm and is formed by a thermal spraying method.
The short sleeves 82 and 92 are made of JIS / SUS304, have an outer diameter of 180 mm, an inner diameter of 120 mm, and a length of 155 mm.

The insulation resistance between the adjacent short sleeves 52 and 62 of the metal cylinder heating device 40 was measured with a commercially available general mega, and the lowest was 1 MΩ, which was 5 MΩ, 12 MΩ, 20 MΩ, 27 MΩ, and 30 MΩ. The others were endless.
Moreover, when the insulation resistance of adjacent short length sleeves 82 and 92 of the metal cylinder heating device 70 was measured with the same megger, all were infinite.

When the runout was measured by operating with no load, it was 0.02 mm or less for the receiving rollers 50 and 60 of the metal cylinder heating device 40, and 0.02 to 0 for the receiving rollers 80 and 90 of the metal cylinder heating device 70. 0.05 mm.
On the other hand, when the metal cylinder 10 for test was mounted and a load operation was performed, the deflection of the receiving rollers 50 and 60 of the metal cylinder heating device 40 increased to about 0.25 mm. The deflection of the receiving rollers 80 and 90 of the body heating device 70 was only 0.05 to 0.07 mm.

  Furthermore, induction heating was performed by energizing the inductor 22 with high frequency, and the temperature of the metal cylinder 10, the temperature of the cover exposing portion 74 of the intermediate bearing portion 72, and the temperature of the bearing of the intermediate bearing portion 72 were measured. It became as follows. That is, when the cylinder temperature is 600 ° C., the cover temperature is 24 ° C. and the bearing temperature is 42 ° C., and when the cylinder temperature is 700 ° C., the cover temperature is 25 ° C. and the bearing temperature is 42 ° C., and the cylinder temperature is Cover temperature is 30 ° C. and bearing temperature is 44 ° C. at 850 ° C. Cover temperature is 35 ° C. and bearing temperature is 75 ° C. when cylinder temperature is 950 ° C. Cover temperature when cylinder temperature is 1050 ° C. Was 38 ° C. and the bearing temperature was 68 ° C.

And the process of heating and raising to 1050 ° C. while rotating the metal cylinder 10 at 15 revolutions / second, maintaining the state for 10 seconds, and then lowering the metal cylinder 10 to room temperature was repeated.
In the case of the conventional metal cylinder heating device 20, when such a process is repeated about 10 times, a visible spark mark appears on the receiving rollers 23 and 24. In the metal cylinder heating device 70, even if the above process is repeated 100 times or more, no spark mark appears on the receiving rollers 50, 60, 80, 90, and the above process is continued.

[Others]
In the above embodiment, a saddle-shaped induction coil is used as the inductor 22. However, this is merely an example, and the inductor can have other shapes as long as it can heat the entire length of the metal cylinder. For example, a face-fired coil or a multi-turn coil described in Patent Document 1 may be used.
Further, the metal cylinder heating device of the present invention is not limited to the self-fluxing alloy coating construction on the circumferential surface of the metal cylinder, and can be used for heat treatment of rollers, for example.

Furthermore, in the above-described embodiment, the press roller described in Patent Document 1 is not provided. However, the press roller may be arbitrarily provided as long as it does not interfere with other members.
Further, in the above embodiment, the rotation drive by the electric motor is performed only for one receiving roller, but a plurality of receiving rollers may be driven if rotation synchronization is appropriately taken. .

  FIG. 8 is a detailed side view centered on one end of the receiving roller 51, and shows a part of the short sleeve, such as the upper half, in cross section. The stopper 55 shown here is shaped like an angle member. One end is fixed to the end surface of the receiving roller 51 with a bolt 55a, and the other end is in contact with the end surface of the short sleeve on the outer peripheral surface of the receiving roller 51.

1A is a perspective view showing an overall structure of a metal cylinder heating device, FIG. 1B is a perspective view showing a use state, and FIG. 2C is a secondary induced current induced in a receiving roller. FIG. It is a top view of two receiving rollers. The external structure of each part of the receiving roller is shown, (a) is a perspective view of a core member, (b) is a perspective view of a short sleeve, (c) is a perspective view of an insulating spacer, and (d) is a developed view of the receiving roller. is there. The internal structure of each part of the receiving roller is shown, (a) is a front view of the receiving roller, (b) is an AA cross-sectional arrow view, (c) is a BB cross-sectional arrow view, (d) is a partially enlarged view thereof, (e ) Is an enlarged front view of part C, (f) is a sectional view thereof, and (g) is a partially enlarged view thereof. It is a perspective view which shows the whole structure of a metal cylinder heating apparatus about other embodiment of this invention. It is a top view of two receiving rollers. It is the front view and side view of an intermediate bearing part. It is a partial cross section side view of a receiving roller edge part. Regarding a conventional metal cylinder heating device, (a) is a perspective view showing the structure and use state, (b) is a perspective view showing a primary induced current induced in the metal cylinder, and (c) is induced in the receiving roller. It is a perspective view which shows the secondary induced current. (A) is a perspective view showing a structure and a usage state of a metal cylinder heating device in which an insulating coating is applied to a receiving roller, and (b) and (c) are secondary induced currents induced in the receiving roller. It is a perspective view shown.

Explanation of symbols

10 Metal cylinder (work)
11 Primary induced current (induced to metal cylinder)
12 Secondary induced current (induced to the receiving roller)
13, 14, 15, 16 End of rolling surface (discharge frequent occurrence part)
20 Metal cylinder heating device (Metal cylinder heating device)
21 High frequency power supply (induction heating device)
22 Inductor (coil, induction heating device)
23, 24 Receiving roller (main part of cylindrical body supporting rotating device)
25 Both end bearing (shaft support, roller drive)
26 Electric motor (rotation drive source, roller drive device)
30 Metal cylinder heating device (Metal cylinder heating device)
33, 34 Receiving roller (main part of cylindrical support rotating device)
40 Metal cylinder heating device (Metal cylinder heating device)
50, 60 Receiving roller (main part of cylindrical support rotating device)
51, 61 Core member (metal shaft, insulation coating on outer peripheral surface)
51a Key member 51b Hollow 52, 62 Short sleeve (Stainless tubular body capable of shrink fitting)
52a Key groove 53, 63 End gap (electrical insulation means)
54 Spacer (electrical insulation means)
54a Short sleeve separation part 54b Held part 55 Stopper (electrical insulation means, drop-off prevention means)
70 Metal cylinder heating device (Metal cylinder heating device)
71 Insulation plate (ground insulation means)
72 Intermediate bearing (shaft support, roller drive)
73 Water passage (water cooling cover for radiant heat shielding)
74 Exposed part (Water-cooled cover for radiant heat shielding)
80, 90 Receiving roller (main part of cylinder support rotating device)
81,91 core member (metal shaft, insulation coating on outer peripheral surface)
82,92 Short sleeve (Stainless tube that can be shrink fitted)

Claims (7)

  A metal provided with a receiving roller having a two-row structure that supports a metal cylinder to be heated while rotating, a roller driving device that rotationally drives the receiving roller, and an induction heating device that induction-heats the metal cylinder at the same time. In the cylindrical heating device, the receiving roller has a structure in which a metal sleeve is fitted to a metal core member, and the sleeve is divided into a plurality of short sleeves, and the core member and A metal cylinder heating device, wherein the metal cylinder heating device is fitted in an electrically insulated state and an arrangement in which a gap is provided between the short sleeves.   The means for electrically insulating the plurality of short sleeves from the core member is an electrically insulating coating applied to an outer peripheral surface of the core member or an inner peripheral surface of the short sleeve, The metal cylinder heating device according to claim 1, wherein the metal member is tightly fitted to the core member via a pin.   A key groove extending over the entire length of the short sleeve is provided on the inner peripheral surface of the short sleeve, and a key member is implanted on the outer peripheral surface of the core member, and the short sleeve is formed in the key groove. The key member is protruded to be fixed in the circumferential direction with respect to the core member, and further, by an electrically insulating spacer disposed between the short sleeves by key engagement with the key grooves of the short sleeves, The heating apparatus for a metal cylinder according to claim 1, wherein the gap between the short sleeves is maintained.   The metal cylinder heating device according to claim 3, wherein a stopper for preventing the short sleeve from falling off is disposed at an end of the core member.   2. The metal cylinder heating device according to claim 1, wherein the sleeve is made of a nonmagnetic metal.   6. The heating device for a metal cylinder according to claim 1, wherein the roller driving device is ground-insulated.   7. The roller driving device is provided with both end bearing portions that pivotally support an end portion of the core member and an intermediate bearing portion that pivotally supports an intermediate portion of the core member. The heating apparatus of the metal cylinder of description.

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