JP2005146316A - Method and apparatus for hardening rolling contact surface of metallic rotating ring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the voltage exceeding a regulated value from being applied to a worker when the induction-heating is performed with a large circle heating so as not to form a soft zone, even in the case of induction-heating a rolling-contact surface of a large diameter metallic rotating ring. <P>SOLUTION: When the rolling-contact surface 23a of the metallic rotating ring 23 is hardened by utilizing the induction-heating, the plurality of inductors 30a, 30b, 30c are connected in the annular state so as to be faced to the rolling-contact surface 23a, and the large circle heating is performed by supplying the high-frequency current to these inductors 30. At this time, the voltage having ≤600V is applied to each of the inductors 30a, 30b, 30c and the voltage exceeding 600V in the total is applied. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a method and apparatus for quenching a rolling contact surface of a large-diameter metal turning wheel used in a turning part of a large machine. As a large machine having a swivel unit, a construction machine and a civil engineering machine such as a power shovel, a bulldozer, and a large crane are typical, but a large windmill is also included.
The “metal swivel ring” in this specification refers to a rolling bearing bearing ring (bearing race) having a large diameter with an outer diameter of 1 m or more, and is special because it has a large diameter. It is manufactured by the manufacturing method.

  In other words, if the outer ring used for a general-purpose bearing has an outer diameter of less than 1 m, the above quenching is performed, for example, in a gas furnace or a carburizing furnace, and in the case of small articles, a plurality of bodies are heated together. In contrast to mass production, large-sized metal swivel wheels are economical in equipment, wasteful energy consumption associated with scale-up including parts that do not require heating, and difficult handling due to large size (especially, Because it is not suitable for overall heating due to the combination of heating that is easy to deform, etc., a single quenching process using induction heating is applied only to the surface layer of the rolling contact surface that requires improved wear resistance. Done. And the various features derived from the above-mentioned large diameter have brought various technical problems to the induction heating type quenching treatment.

  Some metal turning wheels used for turning parts of large machines have a large diameter exceeding 3 m. Therefore, the well-known circumferential moving hardening is used for quenching the rolling contact surface of metal turning wheels. The method is heavily used. In this circumferential movement quenching method (see FIG. 13), a relatively small area that occupies a partial section in the circumferential direction of the rolling contact surface 11 (in the illustrated example, the inner peripheral surface) of the metal turning wheel 10 is relatively heated. The small inductor 12 is opposed to the rolling contact surface, and the rolling contact surface and the inductor 12 are moved relative to each other in the circumferential direction, and are used for turning parts such as construction machines and civil engineering machines. Satisfactory effects are given for the metal turning wheels.

  In the circumferential direction moving quenching method, quenching is started from one place on the rolling contact surface 11, and the quenching is finished after quenching almost the entire circumference of the annular rolling contact surface 11. If the part 13 and the stop part 14 overlap, quench cracks may occur, so that a soft zone 15 that is a non-quenched part is inserted between the start part (quenching start point) and the stop part (quenching end point). (For example, refer to Patent Document 1).

  In addition, heating of an explosion-proof belt attached to a used cathode ray tube is known as an application example of induction heating, although it is not quenching of a metal swirl wheel (see, for example, Patent Document 2). This is different from the partial quenching of the rolling contact surface for the large-diameter metal swirling wheel, but the entire belt is heated as in the case of the small-diameter general-purpose bearing, but it differs from the quenching of the small-diameter general-purpose bearing in that the ultimate temperature is low. The point that the coil element is divided into four parts corresponding to the square shape of the cathode ray tube, and the positioning means such as a cylinder device that changes the position of the coil element to suit various sizes of the cathode ray tube are provided. It is characteristic.

In addition to serial connection, the power supply mode may be parallel or series-parallel, and a specific example relating thereto is disclosed a connection example in which power is appropriately branched from a pair of power supply lines (see FIG. 5 of Patent Document 2).
In addition, another example in which parallel connection is used when performing high-frequency energization to a plurality of inductors is also known (see, for example, Patent Document 3). The power supply device is also specified in this, and the power supply lines leading to each inductor are connected at a branch point to be combined into a pair, and high frequency current is supplied from one power supply device through the pair of power supply lines. It is like that.

Japanese Examined Patent Publication No. 2-48604 (Page 1, Fig. 5) JP 2000-3778 (first page, FIG. 5) JP-A-11-209865 (FIG. 7)

  By the way, the soft zone described above is more easily worn than the hardened part. However, power shovels and bulldozers have dead points that limit the turning angle and turning range to less than 360 °. If the metal swivel wheel is used with the soft zone of the dynamic contact surface, the mechanical load on the soft zone can be reduced, so there is a problem that the life of the metal swirl wheel is inconveniently shortened due to wear of the soft zone due to rolling. There is virtually no. Moreover, since these machines are in an intermittent operation and the operation time is short, the wear of the soft zone and the chance of loading are also small, and the metal swirling wheel has a long life.

On the other hand, a turning part such as a windmill of a wind power plant does not have such a dead point, and intermittent operation cannot be expected. Wind turbines for wind power generation are free to rotate for a long time without restrictions on the turning angle and turning range, but if a metal turning wheel with a soft zone is used for the turning part of such a machine or device, the rolling contact surface As a matter of course, the soft zone portion that has not been hardened wears faster than other portions that have been hardened. As a result, the life of the metal swirling wheel is dominated by the wear of the soft zone, and the metal swirling wheel becomes unusable even though the hardened rolling contact surface remains almost normal. It reaches.
For such soft zone wear, the situation is improved to a considerable extent by forming the soft zone diagonally to alleviate intensive wear of the soft zone (see, for example, Patent Document 1). can do.

  However, in recent years, wind turbines have become larger, and the load on the rolling contact surface has increased. Therefore, measures to mitigate the effects of the soft zone are not sufficient, and the soft zone itself is eliminated from the rolling contact surface. Was requested. In order to respond to such a request, it is necessary to give up the circumferentially moving quenching method that has been widely used, and to adopt another quenching method. However, in the case of a large-diameter metal turning wheel with an outer diameter exceeding 1 m, it is difficult to heat the entire surface like a general-purpose bearing race, so induction can be performed by selecting only part of the surface and heating it. A fundamental problem is to improve the heating method so that no soft zone is formed even if the rolling contact surface is quenched.

  And in order to solve such a basic problem, when performing quenching treatment on the rolling contact surface of the metal swirl ring using induction heating, an annular inductor is made to face the rolling contact surface, and the induction By applying high-frequency energization to the child, all or a part of the rolling contact surface, for example, the outer peripheral surface, inner peripheral surface, end surface, etc. of the metal swirl ring is heated to a great circle, and then the heated portion is cooled by a cooling means ( It is conceivable that the first cooling means is used for cooling. In the induction heating, the inductor having an appropriate width suitable for induction heating is used, and when it is opposed to the rolling contact surface, an appropriate gap suitable for induction heating is taken. . In addition, the above-mentioned “large circle heating” means that the annular rolling contact surface is inductively heated all around the circumference simultaneously by generating an induction current that circulates around the entire circumference of the contact surface as a closed loop electric circuit (hereinafter referred to as a great circle circumference). Pointing.

In this case, an electric current is induced on the rolling contact surface by the inductor during induction heating, but since the inductor has an annular shape that can be heated by a large circle, an induced current that circulates the entire circumference of the rolling contact surface is generated. As a result, the processing target portion of the rolling contact surface is uniformly heated all around, and then the heating portion is cooled.
As a result, the rolling contact surface is uniformly hardened in a circumferentially continuous shape, and therefore, a soft zone cannot be generated, so that the rolling contact surface has no soft zone. It is possible to provide a metal swirling wheel provided with the above.

  However, when the rolling contact surface of the metal slewing ring was actually quenched by such a method of heating with a great circle, satisfactory results were obtained with the metal slewing ring having an outer diameter of 1 m or 2 m. When the outer diameter of the swivel wheel becomes an extremely large diameter of about 3 m, several further problems to be solved technically occurred. Specifically, (a) the problem that the change in the outer diameter of the metal swirling wheel during induction heating has reached a level that cannot be ignored, and insufficient hardness or unevenness of hardness is likely to occur, (b) multiple rows of rolling contacts In the case of a metal swirling wheel having a surface, elimination of the problem that the hardness is undesirably increased during quenching of a certain rolling contact surface up to another quenched rolling contact surface and the hardness is reduced. (C 3) The provision of a technology that realizes the solution of the above-mentioned problems (a) and (b) in combination with the condition of energizing the inductor so that a significant electric shock risk does not reach the worker.

  To supplement these technical issues, first, regarding (a), the change in the outer diameter is caused by thermal expansion, and the breakdown is the increase in the outer diameter and the accompanying non-rounded strain (inherent in the material). Due to subtle anisotropy). As a result of the outer diameter change reaching a higher level in proportion to the super-large diameter, the increase in the outer diameter leads to a change in the average dimension of the gap with the inductor (decrease on the outer peripheral surface and increase on the inner peripheral surface), mainly the inner diameter. This results in insufficient hardness of the peripheral surface, and non-rounding strain leads to variation in gap size, resulting in hardness spots. That is, the phenomenon that inevitable thermal expansion during heating is not a major obstacle for metal turning wheels with an outer diameter of 1 to 2 m, but a serious obstacle for ultra-large diameter metal turning wheels with an outer diameter of around 3 m. In order to solve this problem, it is necessary to provide a new technique such as heating the rolling contact surface to the quenching temperature while suppressing thermal expansion.

Next, (b) is a problem of heat transfer from the rolling contact surface during heating to another rolling contact surface that is not heated. To solve this, the quenching temperature of the rolling contact surface Therefore, it is a problem to provide a technique for performing heating in a short time in which the surrounding temperature rise due to heat transfer does not reach an inconvenient level.
Further, (c) is a highly difficult problem because the energization condition requires that an extra large diameter and a request for an increase in total heat input accompanying large circle heating be simultaneously satisfied.

  Further, the problem (c) includes a voltage problem and a power problem. The problem of the voltage surface is that when the circumference of the rolling contact surface becomes longer as the diameter of the metal swirl wheel becomes larger, the voltage applied to the annular inductor also increases in the circular heating, and this voltage is based on the electrical equipment standard. Since the specified value may be exceeded, it is a problem to prevent such a high voltage from being applied to the worker. Also, the problem of power is that when the circumference increases with the diameter of the metal swirl wheel, the power supplied to the annular inductor increases with large circle heating, which is the maximum power of the existing high frequency power supply device. Although it may exceed the output, it is a problem that required power is supplied even in such a case.

The present invention solves such a voltage problem, and when rotating induction heating for quenching by great circle heating, there is no risk that an applied voltage exceeding a specified value is applied to the operator. It aims at realizing the quenching method of the contact surface.
In addition, the method and apparatus for quenching the rolling contact surface of the metal swivel wheel of the present invention solves the problem of power in addition to the problem of voltage, so that power exceeding the maximum output of the high frequency power supply can be supplied. The purpose is to do.
Furthermore, the metal quenching wheel rolling contact surface quenching method and apparatus according to the present invention have an object to solve the problem of heat transfer and the problem of size effect in addition to the problems of voltage and power.

  The quenching method (initial claim 1) of the metal slewing ring rolling contact surface of the present invention was devised in order to solve such a problem, and the rolling contact surface of the metal slewing ring using induction heating. In the quenching method of the rolling contact surface of the metal swirl wheel that quenches the metal, when performing the induction heating, a plurality of inductors are arranged in a ring-like manner so as to face the rolling contact surface, and high frequency current is supplied to these inductors. In this case, the number of inductors is determined so that a desired induced electromotive force can be obtained under the condition that a voltage of 600 V or less is applied to each of the inductors during the high-frequency energization. It is characterized by keeping.

  Here, the “large circle heating” mentioned above, as described above, generates an induced current that makes a large circle around the annular rolling contact surface (that is, turns around the entire circumference of the rolling contact surface as a closed loop electric circuit). Induction heating at the same time around the entire circumference. The entire circumference may be induction-heated at the same time in the circumferential direction, and the entire width of the rolling contact surface may be the target or a part of the width may be the target in the width direction. Specifically, simultaneous heating of the entire rolling contact surface (entire full width) corresponds to great circle heating. Heating the entire outer peripheral surface portion, the inner peripheral surface portion, or both or both end surfaces of the metal swirling wheel in the rolling contact surface simultaneously corresponds to great circle heating. Heating the entire circumferential direction at the same time in any one of the narrow annular regions obtained by dividing the rolling contact surface into a ring shape also corresponds to great circle heating. On the other hand, the induction heating that locally heats a part of the rolling contact surface in the circumferential direction mainly generates an induced current that circulates locally (that is, not the large circle). This does not apply to the great circle heating.

In addition, the method of quenching a metal swirl ring rolling contact surface according to the present invention (initial claim 2) is the method of quenching a metal swirl ring rolling contact surface according to the initial claim 1 described above, and is further insulated from each other upon the high-frequency energization. In-phase current is supplied from a plurality of power supplies.
Further, the metal turning wheel rolling contact surface quenching device of the present invention (initial claim 3) is a metal turning wheel rolling contact surface quenching device that quenches the rolling contact surface of the metal turning wheel using induction heating. A pedestal for supporting the metal swirl wheel, a plurality of inductors arranged in a ring so as to face the rolling contact surface, a plurality of power supply devices capable of controlling the phase of the output current, and outputs thereof And a common-mode control circuit that makes the phases of the currents the same.

Moreover, the hardening method and apparatus (initial claim 4) of the metal turning wheel rolling contact surface of the present invention are the quenching method of the metal turning wheel rolling contact surface according to the above-mentioned initial claim 2, and further the metal turning wheel. The rolling contact surface is quenched while rotating in the circumferential direction relative to the inductor.
Moreover, the metal turning wheel rolling contact surface quenching device according to the present invention (initial claim 5) is the metal turning wheel rolling contact surface quenching device according to the above-mentioned initial claim 3, further comprising the metal turning wheel as the quenching device. A rotation mechanism that rotates in the circumferential direction relative to the inductor is provided.

Moreover, the quenching method (initial claim 6) of the metal turning ring rolling contact surface of the present invention is the quenching method of the metal turning ring rolling contact surface according to the initial claims 2 and 4, further comprising the metal turning ring. The rolling contact surface is quenched while cooling a surface opposite to the surface facing the inductor in a cooling device.
Further, a metal turning wheel rolling contact surface quenching device according to the present invention (initial claim 7) is the metal turning wheel rolling contact surface quenching device according to the above initial claims 3 and 5, further comprising the inductor and Is provided with a cooling device provided at a position facing the metal swivel ring from the opposite side to cool the metal swivel ring simultaneously in the circumferential direction.

Moreover, the quenching method (initial claim 8) of the metal turning wheel rolling contact surface according to the present invention is the quenching method of the metal turning wheel rolling contact surface according to the above initial claims 2, 4 and 6, further comprising the induction. When heating is performed, the inductor is moved in the diameter expansion direction following the diameter expansion of the metal swirl wheel due to thermal expansion.
Further, the metal turning wheel rolling contact surface quenching device of the present invention (initial claim 9) is the metal turning wheel rolling contact surface quenching device according to the above initial claims 3, 5 and 7, further comprising the metal A moving mechanism for moving the inductor in the radial direction of the turning wheel, and a follow-up control means for operating the moving mechanism according to the diameter expansion of the metal turning wheel are provided.

  In such a quenching method of the metal turning wheel rolling contact surface according to the present invention (initial claim 1), as described above, the inductor has an annular shape capable of heating with a great circle, and the rolling contact surface Since an induced current that circulates the entire circumference of the rolling contact surface is generated, the processing target portion of the rolling contact surface is heated uniformly throughout the entire circumference, and then the heated portion is cooled. Since quenching is performed uniformly on the entire circumference in an unbroken shape, a soft zone cannot occur.

  In addition, the inductor is divided into a plurality of parts and arranged in a ring, and a desired induced electromotive force can be obtained under the condition that a voltage of 600 V or less is applied to each of the inductors during high-frequency energization. Thus, by setting the numerical value of the plural number of inductors, even if the applied voltage of each inductor is 600 V or less, it is possible to apply a voltage exceeding 600 V in total. And by doing so, even if a rolling contact surface is long, great circle heating can be performed with an appropriate voltage, so that it is possible to adapt to an increase in the diameter of the metal turning wheel.

Furthermore, the voltage applied to each inductor, that is, the voltage across each inductor does not exceed 600V, so that even if the operator touches the inductor accidentally and gets an electric shock The safety of the person can be maintained, and the refrigerant can be used with inexpensive tap water or the like.
Therefore, according to the present invention, when performing induction heating for quenching by great circle heating, there is no risk that an applied voltage exceeding a specified value is applied to the worker, and the metal rotating wheel rolling contact surface that is sufficient for the refrigerant to be inexpensive. The quenching method can be realized.

  Further, in the quenching method (initial claim 2) and apparatus (initial claim 3) of the rolling contact surface of the metal swirling wheel according to the present invention, not only the inductor but also the high-frequency power supply device are made plural and their outputs are also made. By making the current phase the same, the total power required for heating the large circle can be divided so that each high frequency power supply can share small power, and the currents in the same phase work together. As a result, an inductive current of a great circle is generated, so that the total power exceeding the maximum output of each high frequency power supply device can be supplied for the great circle heating. Note that the number of inductors and high frequency power supply devices may be the same or different, such as by dividing the inductors into appropriate groups or subsets and allocating one or more high frequency power supply devices to each group. The power may be shared.

  Further, according to the method of quenching the rolling contact surface of the metal swirl ring of the present invention (initial claim 4) and the apparatus (initial claim 5), the metal swirl ring is guided when the large-diameter metal swirl ring is heated to a great circle. By rotating relative to the circumferential direction with respect to the child, even if the metal swirling wheel is deformed or displaced due to thermal expansion, the influence is averaged in the circumferential direction. The expression of unevenness is suppressed. In particular, in the present invention in which the inductor is divided in the circumferential direction, the induction current tends to be dispersed because the inductor is not present at the divided portion, and the inductor is present and heated. Since the states are somewhat different, the quenching state can be made uniform evenly by averaging the influence in the circumferential direction.

  Moreover, in the quenching method (initial claim 6) and the apparatus (initial claim 7) of the rolling contact surface of the metal swirl ring of the present invention, the opposite side is cooled when the large-diameter metal swirl ring is heated to a great circle. As a result, even if the total heat input amount is large, an increase in the average temperature of the metal swirl wheel is suppressed, so that the deformation amount of the metal swirl wheel is reduced. It also helps prevent the hardness of the hardened parts from decreasing. Therefore, according to the present invention, it is possible to solve the problem of heat transfer in addition to the problems of voltage and power.

  Moreover, in the quenching method (initial claim 8) and the apparatus (initial claim 9) of the metal turning wheel rolling contact surface of the present invention, the inductors are divided and arranged in an annular shape, and each of them is effortless in the radial direction. When the metal swirling wheel is thermally expanded by induction heating and its diameter is expanded by utilizing the fact that it is movable, the inductor moves following the diameter expansion of the metal swirling wheel even during induction heating. By doing so, the facing distance between the rolling contact surface of the metal turning wheel and each inductor is always kept at an appropriate distance. Therefore, according to the present invention, it is possible to solve not only the problem of voltage and power but also the problem of size effect.

  One embodiment of a quenching method and apparatus for a metal turning wheel rolling contact surface of the present invention will be described with reference to the drawings. First, the metal turning wheel 20 to be quenched will be described with reference to FIGS. 1 and 2, and the structure of the quenching device 40 will be described with reference to FIGS. 3 shows the structure of the inductor 30 for end face heating, FIG. 4 shows the overall structure of the quenching device 40, FIG. 5 shows the configuration of the high-frequency power supply device 50, and FIG. 6 shows the first and second cooling means. Is shown.

  First, the metal turning wheel 20 whose specific example is shown in FIGS. 1 and 2 will be described. 1A and 1B show the assembled state, FIGS. 1C and 1D show the unfolded state, FIG. 1A is a perspective view of the metal turning wheel 20, and FIG. An enlarged sectional view, (c) is an exploded perspective view of each ring constituting the metal turning wheel 20, and (d) is a partially enlarged sectional view thereof. 2A is a partially enlarged sectional view showing the retaining ring and its rolling contact surface, FIG. 2B is a partially enlarged sectional view showing the nose ring and its rolling contact surface, and FIG. It is a partial cross section enlarged view which shows a ring and its rolling contact surface.

  The metal turning wheel 20 (see FIG. 1) includes a retaining ring 21 that forms the upper half of the outer ring, a nose ring 22 that forms the inner ring, a support ring 23 that forms the lower half of the outer ring, a retaining ring 21 and a nose ring 22. And a large number of rollers 24 that roll while being interposed between the nose ring 22 and the support ring 23. Each ring 21 to 23 has a rolling contact surface on which rollers 24 to 26 roll, and in order to strengthen it by quenching, rings 21 to 23 are made of steel such as SCM and SNCM, and other quenchable metals. Made with.

  The rolling contact surface is an annular continuous belt-like surface, and is roughly classified into an end surface, an inner peripheral surface and an outer peripheral surface. Specifically, the portion of the downward end surface of the retaining ring 21 that contacts the roller 24 is the rolling contact surface 21a (see FIG. 2A), and the entire outer peripheral surface of the nose ring 22 contacts the roller 26. Rolling contact surface 22a (refer to FIG. 2 (b)), and portions of the upper and lower end surfaces of the nose ring 22 that are in contact with the rollers 24 and 25 are rolling contact surfaces 22b (refer to FIG. 2 (b)). A portion of the upward end surface of the support ring 23 that contacts the roller 25 is a rolling contact surface 23a (see FIG. 2C), and a portion of the inner peripheral surface of the support ring 23 that contacts the roller 26 is rolling contact. It is the surface 23b (refer FIG.2 (c)). The downward end face can be treated in the same manner as the upward end face by turning the ring upside down during quenching (see the two-dot chain line in FIG. 2A).

The structure of the inductor 30 for end face heating shown in FIG. 3 will be described. 3A is a perspective view of the support ring 23 and the inductor 30 corresponding to the rolling contact surface 23a positioned on the upward end surface thereof, and FIG. 3B is an enlarged partial cross-sectional view of the inductor 30. FIG. (C) is a longitudinal cross-sectional view of the inductor 30 and the support ring 23 in an opposed state, and (d) is a partially enlarged view thereof.
The inductor 30 is obtained by dividing a coil for approximately one turn into a plurality of inductors 30a, 30b, and 30c and arranging them in a ring. In the following, when identifying each of the divided inductors, reference numerals “30a”, “30b”, and “30c” are attached, and when referring to any appropriate inductor without distinction, When referring to a column, the reference numeral “30” is attached.

  The inductors 30a, 30b, and 30c are all made of a good conductor such as copper for high-frequency energization, and other than the energization ends 31 and 32, the other portions are continuous. In the illustrated example, the inductor 30 is divided into three, but the number of divisions of the inductor 30 is not limited to three, and is determined based on the total voltage of high-frequency energization to the inductor 30. In other words, when the total voltage is 600 V or less, it is optional to not divide, but when the total voltage exceeds 600 V, it is sufficient to divide immediately and apply any voltage of 600 V or less to any of the divided inductors. Like that.

The division of the inductor 30 may be unequal, but is usually divided equally. Therefore, dividing the total voltage by 600V and rounding up the fraction results in the minimum division number. The three divisions shown are typical examples when the total voltage is more than 1200V and less than 1800V, and the inductors 30a, 30b, and 30c are all arcuate with a central angle of less than 120 °.
The total voltage of high-frequency energization to the inductor 30 is determined by the material of the support ring 23 (metal turning wheel), the width and length of the rolling contact surface 23a, and the quenching conditions. Of these, the material, width, and length are generally determined by the required specifications from the outside, but the quenching conditions, especially the heating conditions, are selected so as to satisfy the required specifications such as hardness. When performing circular heating, it is desirable to perform high-frequency energization so that the surface power density is 200 W / cm ² or more.

Then, since the heating surface rapidly rises in temperature, the heating required for quenching can be completed in a short time, so the total amount of heat input is reduced. The deformation amount of the ring is reduced. In addition, it is useful for preventing a decrease in hardness of the quenched part.
When the surface power density is determined, the power of the high-frequency energization is determined from the surface contact area 23a and the area of the rolling contact surface 23a. Further, the frequency of the high-frequency energization appropriately selected in consideration of the heating depth, etc. From this, the total voltage is determined.

  Inductors 30 are arranged in an annular shape having substantially the same diameter as the rolling contact surface 23a in order to heat the rolling contact surface 23a by one-round heating. It can be confronted. In addition, the lower surface of the inductor 30 is flat so that the respective portions face each other at an equal distance over substantially the entire circumference of the rolling contact surface 23a. Furthermore, since this inductor 30 also serves as an action part of the first cooling means described later, it is formed of a hollow tube to carry water for cooling, and is formed on the lower surface that is the surface facing the rolling contact surface 23a. A large number of injection holes 34 are perforated.

The quenching device 40 shown in FIG. 4 as a front view and a left side view includes a base 41, a lifting mechanism 42, and a position adjusting mechanism for holding the inductor 30 in which the inductors 30a, 30b, 30c are arranged in an annular shape. 43 and a suspension mechanism 44, and a gantry 45 for supporting a metal turning wheel to be quenched, for example, the support ring 23.
The disk 46 at the top of the gantry 45 is provided horizontally, and an appropriate fastener such as a protrusion is attached to the upper surface. When the support ring 23 is placed with the rolling contact surface 23a facing upward, It is designed to provide stable support while lying down.

  In order to make the lower surface of the inductor 30 face the rolling contact surface 23 a of the support ring 23, the suspension mechanism 44 that suspends the inductor 30 above the disk 46 includes a position adjustment mechanism 43 and a lifting mechanism 42. And is connected to and supported by the base 41. The base part 41 is installed at a position away from the gantry 45 so as not to interfere. The elevating mechanism 42 elevates and lowers the position adjusting mechanism 43 in the vertical direction. The position adjusting mechanism 43 moves the suspension mechanism 44 horizontally. The suspension mechanism 44 is a lightweight link mechanism and includes a length adjusting screw for horizontally suspending the inductor 30.

  Although illustration is omitted here, three high-frequency cables (three pairs of secondary-side electric paths 56) extending from a high-frequency power supply device (50), which will be described later, to the current-carrying ends 31, 32 of the inductor 30, that is, the inductors 30a, 30b, 30c ) And the water supply pipe (first cooling means) to the inductor 30, that is, the inductors 30 a, 30 b, and 30 c are also wired and piped so as not to interfere with the support ring 23 using the suspension mechanism 44.

  The high-frequency power supply device 50 shown in the block diagram of FIG. 5 is of an insulation type and can further variably set the frequency. The high frequency power supply device 50 converts the AC power of a predetermined frequency supplied from the AC source 51 into a direct current by the rectifying unit 52, converts it into a high frequency of a desired frequency by the inverter 53, and outputs it. A transformer between a pair of power supply circuits 54 (primary side circuit) and three pairs of secondary side circuits 56 connected to the inductors 30, that is, the current-carrying ends 31 and 32 of the inductors 30 a, 30 b, and 30 c. 55 is inserted and connected. The secondary windings of the insulation transformer 55 are aligned in the same winding direction with respect to the primary windings so that the currents output to the three pairs of secondary electric paths 56 are in phase.

  If a non-insulated transformer is incorporated in the high frequency power supply device, the ground voltage of the inductor 30 is equal to the output voltage of the inverter 53 at a high place, or the output voltage of the inverter 53 depends on the turn ratio of the non-insulated transformer. Get higher. Although the secondary side electric circuit 56 is concealed by an insulated cable or the like, since the inductor 30 is exposed, it is desirable that the ground voltage of the inductor 30 does not increase for the safety of the operator.

  In this respect, the high frequency power supply device 50 incorporates an insulation transformer 55, and the insulation transformer 55 insulates the power supply circuit 54 and the secondary side circuit 56 with respect to the energization frequency not exceeding 30 kHz. Inductors 30a, 30b, and 30c are all floated from the ground, and only a voltage of 600V or less is applied. Therefore, if the frequency is close to the low frequency, which is frequently used for induction heating for quenching. The voltage exceeding 600V is not applied to the worker regardless of where the worker touches the inductor 30, including the ground voltage.

For this reason, even if an operator accidentally touches the inductor 30, there is no great electric shock, so it is relatively safe. In this embodiment, the high frequency power supply device 50 incorporating the insulating transformer 55 is used.
The inverter 53 of the high-frequency power supply device 50 is controlled to start and stop high-frequency energization by a control device (controller) (not shown), and the high-frequency frequency is variably controlled. That is, when the operator designates and sets a desired time and frequency to the control device, the high frequency power supply device 50 supplies the inductor 30 with a high frequency of that frequency for the designated time.

  Further, the high-frequency power supply device 50 reduces the voltage Vc across the divided inductor 30, that is, the supply voltage applied to the current-carrying ends 31 and 32 of the inductors 30 a, 30 b, and 30 c via the secondary side electric circuit 56 to 600 V or less. Therefore, the voltage Vc across the inductors 30a, 30b, and 30c is measured. To measure the voltage Vc at both ends, it is accurate to measure the secondary voltage of the insulation transformer 55 with a high-frequency voltmeter (not shown). Alternatively, a value obtained by dividing the output voltage of the high-frequency power supply device 50 by the turn ratio of the insulation transformer 55 may be used. The voltage Vc across the inductor 30 is lowered by the amount of the impedance drop, but there is no problem because it is on the safe side.

The first cooling means whose sectional structure is shown in FIG. 6 (a) is one in which the operating part is integrated with the inductor 30, and the cooling supplied to the hollow of the inductor 30 to cool the heating surface. Water 35 (refrigerant) is sprayed from the injection port 34 to the rolling contact surface 23a after heating.
The cooling device 70 (second cooling means) whose cross-sectional structure is shown in FIG. 6B has an operating part integrated with the disk 46, and in the support ring 23, the rolling contact surface 23a to be heated and In order to cool the opposite surface located on the opposite side, a water flow groove 46a is carved and formed in the upper surface of the disk 46 that supports the lower surface of the support ring 23 where the opposite surface hits. Cooling water 72 is supplied and water is passed. Since the voltage Vc across the inductor 30 is 600 V or less, inexpensive tap water is used for the cooling water 35 and 72.

  A method of quenching the rolling contact surface 23a of the support ring 23 using such a quenching apparatus 40 will be described.

Prior to quenching the end face of the metal swirl ring, in order to perform high-frequency energization such that the surface power density is 200 W / cm ² or more, the power for high-frequency energization is determined from the surface power density and the area of the rolling contact surface 23a. At the same time, the frequency of high-frequency energization is selected in consideration of the heating depth and the like, and is further applied to the inductor 30 from the material of the support ring 23 (metal swirl ring) and the width / length of the rolling contact surface 23a. Find the total voltage. Here, it is assumed that the total voltage is 1800 V or less and the inductor 30 is divided into the inductors 30a, 30b, and 30c. It is assumed that the power can be supplied without difficulty from one high-frequency power supply device 50 at, for example, about 1000 kW. It is assumed that the frequency can be set to the normal inverter 53 at, for example, about 3 kHz or 6 kHz.

  If such a high frequency power supply device 50 is selected, the rolling contact surface 23a is quenched by one-time heating. Specifically, the above-described inductor 30, that is, the inductors 30 a, 30 b, and 30 c are also annularly mounted on the quenching device 40 described above, and the selected high-frequency power supply device 50 is connected to the three energization ends 31 and 32. Are connected to each other, the support ring 23 is placed on the disk 46 of the gantry 45, and the lifting mechanism 42 and the position adjusting mechanism 43 of the quenching device 40 are operated so that the inductor 30 is moved. It is made to oppose with the suitable space | gap, for example, 15 mm, to the rolling contact surface 23a. Then, the high frequency power supply device 50 is operated to output a high frequency of the above frequency at the output voltage.

Then, a predetermined time corresponding to the quenching condition, or a time until the temperature reaches the predetermined temperature of the quenching condition while measuring the temperature of the heating surface, that is, the rolling contact surface 23a, the inductor 30 Inductive heating is performed by applying high-frequency current to, and then high-frequency current is stopped. Then, the cooling water 35 is blown out from the injection port 34 to cool the rolling contact surface 23a. Note that the cooling means of the quenching apparatus 40 may be the first cooling means for supplying the cooling water 35 to the inductor 30 and the cooling apparatus 70 of the second cooling means is better but not essential. The lifting mechanism 42 and the position adjusting mechanism 43 may be omitted as long as the inductor 30 can be positioned by other means.
Finally, when the support ring 23 is cooled, the supply of the cooling water 35 is stopped and the support ring 23 is removed from the gantry 45.

  Thus, in this embodiment, even if the support ring 23 has a large diameter, large-circle heating can be performed without difficulty, and the rolling contact surface 23a is appropriately and appropriately formed by an induced current that makes a large circuit around the rolling contact surface 23a. Since it is sufficiently heated and the average temperature of the support ring 23 is moderately suppressed so as not to cause undesired deformation, quenching without a soft zone can be performed. Although repeated detailed description is omitted, the same applies to the rolling contact surface 21 a located on the end face of the retaining ring 21 and the rolling contact face 22 b located on both end faces of the nose ring 22. Can be quenched.

The configuration of another embodiment of the quenching method and apparatus for the rolling contact surface of a metal swivel wheel of the present invention will be described with reference to the drawings. FIG. 7 is a block diagram of the high-frequency power source used here.
This power supply is configured by combining three high-frequency power supply devices 60 and one in-phase control circuit 68, and one high-frequency power supply device 60 is allocated to each of the inductors 30a, 30b, and 30c. Other than that, for example, the hardening device 40 and the inductor 30 are the same as those described in the above embodiment.

  The high-frequency power supply device 60 is different from the above-described high-frequency power supply device 50 because each of the plurality of insulation transformers 65 in place of the insulation transformer 55 only needs to include one secondary side electric circuit 56. The point is that an inverter 63 in place of the inverter 53 receives the switching control signal A from the common-mode control circuit 68. The common-mode control circuit 68 is a switching control circuit included in the inverter 53 that is separated and independent, and sends the generated switching control signal A to the inverters 63 of the three high-frequency power supply devices 60 at the same time. Yes.

  The inverter 63 may be configured such that the switching control circuit A is omitted from the inverter 53 and the switching control signal A is input from the common-mode control circuit 68. Alternatively, the switching control signal generated internally and the external circuit are left with the switching control circuit remaining. It is also possible to use the switching control signal A that has been input from In any case, the same switching control is performed on three units: the high frequency power supply device 60 for applying high frequency current to the inductor 30a, the high frequency power supply device 60 for supplying high frequency current to the inductor 30b, and the high frequency power supply device 60 for applying high frequency current to the inductor 30c. By providing the signal A so that the frequency and phase of the output current can be controlled, a current having the same phase is supplied to the inductors 30a, 30b, and 30c.

  In this case, the frequency when the inductor 30 is energized with high frequency is collectively set in the in-phase control circuit 68, and the power supplied to the inductors 30a, 30b, 30c is set separately for each high frequency power supply device 60. Therefore, for example, even if the high frequency power supply 60 can supply only up to 1200 kW, if three units can be used, induction heating up to 3600 kW can be achieved by cooperating with the same phase of the output current. It can be carried out.

  In this embodiment, the high frequency power supply devices 60, 60, 60 and the inductors 30a, 30b, 30c are combined on a one-to-one basis, but other combinations are possible as long as the voltage condition and the power condition are satisfied. For example, a combination in which a small output high frequency power supply device is connected to one inductor and a high output high frequency power supply device is connected to two inductors is also possible. If the division of the inductor 30 is subdivided, a high-frequency power supply device with a smaller output can be used. Therefore, selection of a high frequency power supply device becomes easier as the number of devices increases.

The structure of the inductor 30 for heating the inner peripheral surface whose specific example is shown in FIG. 8 will be described. 8A is a perspective view of the support ring 23 and the inductor 30 corresponding to the rolling contact surface 23b located on the inner peripheral surface of the support ring 23. FIG. 8B is an enlarged partial cross-sectional view of the inductor 30. FIG. FIG. 4C is a longitudinal sectional view of the inductor 30 and the support ring 23 in an opposed state, and FIG.
This inductor 30 is also formed by dividing a coil for approximately one turn into a plurality of inductors 30a, 30b, and 30c and arranging them in a ring. The inductors 30a, 30b, and 30c are all made of a good conductor such as copper for high-frequency energization, and other than the energization ends 31 and 32, the other portions are continuous.

  In order to heat the rolling contact surface 23b from the inside, the inductor 30 is arranged in an annular shape having a slightly smaller diameter than the rolling contact surface 23b but a large diameter close to the rolling contact surface 23b. It is possible to confront almost the entire circumference. Moreover, the outer peripheral surface of the inductor 30 is flat so that each part may oppose at equal distance over substantially the entire periphery of the rolling contact surface 23b. Furthermore, since this inductor 30 also serves as the action part of the first cooling means, it is formed of a hollow tube to carry water for cooling, and is formed on the outer peripheral surface that is the surface facing the rolling contact surface 23b. A large number of injection holes 34 are perforated.

The structure of the outer peripheral surface heating inductor 30 whose specific example is shown in FIG. 9 will be described. 9A is a perspective view of the nose ring 22 and the inductor 30 corresponding to the rolling contact surface 22a located on the outer peripheral surface thereof, and FIG. 9B is a partially enlarged cross-sectional view of the inductor 30. c) is a longitudinal sectional view of the inductor 30 and the nose ring 22 in an opposed state, and (d) is a partially enlarged view thereof.
This inductor 30 is also formed by dividing a coil for approximately one turn into a plurality of inductors 30a, 30b, and 30c and arranging them in a ring. The inductors 30a, 30b, and 30c are all made of a good conductor such as copper for high-frequency energization, and other than the energization ends 31 and 32, the other portions are continuous.

  In order to heat the rolling contact surface 22a from the outside, the inductor 30 is arranged in an annular shape having a slightly larger diameter than the rolling contact surface 22a but close to the diameter, and the rolling contact surface 22a. It is possible to confront almost the entire circumference. Further, the inner peripheral surface of the inductor 30 is flat so that the respective portions face each other at an equal distance over substantially the entire circumference of the rolling contact surface 22a. Furthermore, since this inductor 30 also serves as the action part of the first cooling means, it is composed of a hollow tube for carrying water for cooling, and is an inner peripheral surface that is a surface facing the rolling contact surface 22a. A number of injection holes 34 are perforated therethrough.

  A method of quenching the rolling contact surface 22a located on the outer peripheral surface of the nose ring 22 using the inductor 30, the quenching device 40, the high frequency power supply device 50 or the high frequency power supply device 60 will be described with reference to the drawings. explain. FIG. 10 is a partial cross-sectional enlarged view showing quenching by single heating in the order of processes, and FIG. 11 is a partial cross-sectional enlarged view showing quenching in single heating with cooling on the opposite surface in the order of processes.

Prior to quenching the end face of the metal swirl ring, as in the above-described embodiment, the power of high-frequency energization is determined so that the surface power density is 200 W / cm ² or more, and the frequency of high-frequency energization is determined in consideration of the heating depth and the like. The total voltage applied to the inductor 30 is determined from the material of the nose ring 22 and the width / length of the rolling contact surface 22a, the number of divisions of the inductor 30 is determined, and the high-frequency power supply devices 50 and 60 are selected. The connection mode with the inductor 30 is determined. Again, the inductor 30 is divided into three inductors 30a, 30b, 30c, which are arranged in a ring and mounted on the quenching device 40, and the rolling contact surface 22a is quenched by one-time heating. Shall.

  And when cooling from the opposite surface is omitted and the rolling contact surface 22a is quenched (see FIG. 10), an appropriate gap is secured and the inductor 30 is opposed to the rolling contact surface 22a of the nose ring 22. In this state, the inductor 30 is energized with high frequency to inductively heat the rolling contact surface 22a (see FIG. 10B), and then the cooling water 35 is injected into the inductor 30. The rolling contact surface 22a is cooled by spraying from the mouth 34 to the outer peripheral surface of the nose ring 22 (see FIG. 10C).

  On the other hand, when the rolling contact surface 22a is quenched by one-shot heating with cooling on the opposite surface (see FIG. 11), the inductor 30 is opposed to the rolling contact surface 22a of the nose ring 22 and the cooling device is disposed on the opposite surface 22c. 70 water supply pipes 73 are opposed to each other (see FIG. 11A). In this state, cooling water 72 is sprayed from the injection port 74 of the water supply pipe 73 to the inner peripheral surface of the nose ring 22 to cool the opposite surface 22c, while the inductor 30 is energized with high frequency to induction-heat the rolling contact surface 22a. (See FIG. 11B). Thereafter, the cooling water 35 is sprayed from the injection port 34 of the inductor 30 to the nose ring 22 to cool the rolling contact surface 22a (see FIG. 11C).

In this case, the inductor 30 is also used for the one-time heating shown in FIG. 9 and the lifting mechanism 42 is not essential, but the quenching device 40 is not limited to the first cooling means but also the second cooling means (cooling device 70). ).
Also in this case, the number of divisions of the inductor 30 is determined such that only a voltage of 600 V or less is applied to any of the inductors 30a, 30b, 30c, and the high frequency power supply device 50 is used or the high frequency power supply device 60 is used. Is used, or a combination of the two is used as appropriate in consideration of the power condition and the voltage condition.

  Thus, even in this embodiment, even if the nose ring 22 has a large diameter, it is possible to surely carry out a great circle heating, and the rolling contact surface 22a is adequate and sufficient by the induced current that makes a large round of the rolling contact surface 22a. Since the average temperature of the nose ring 22 is moderately suppressed so as not to cause undesired deformation, quenching without a soft zone can be performed with preferable quenching quality. Although repeated detailed description is omitted, the same quenching can be performed on the rolling contact surface 23b located on the inner peripheral surface of the support ring 23 in the same manner.

The configuration of another embodiment of the quenching method and apparatus for the rolling contact surface of a metal swivel wheel of the present invention will be described with reference to the drawings. FIG. 12 is a plan view of portions of the support ring 23 and the inductor 30 that face each other and the diameter expanding means 80 attached thereto.

This quenching apparatus is different from the above-described embodiment in that a diameter expanding means 80 is added.
The diameter expanding means 80 is provided with three sets corresponding to the fact that the inductor 30 is divided into the inductors 30a, 30b and 30c. Each of the diameter expanding means 80 includes a displacement meter 81, a follow-up control circuit 82, and a moving mechanism 83.

  The displacement meter 81 is shown as a contact type so that the installation state and the like can be easily understood. However, since the support ring 23 to be measured is heated to a high temperature, the non-contact type is less likely to be affected by heat. The position of the displacement meter 81 may be a place where the displacement of the support ring 23 facing the intermediate portion of the inductors 30a, 30b, 30c may be detected. In the illustrated case, the divided portion of the inductor 30, that is, the inductor 30a, The displacement of the support ring 23 facing between 30b, between the inductors 30b and 30c, and between the inductors 30c and 30a is detected.

The follow-up control circuit 82 includes, for example, an operational amplifier and a power amplifier. The output of the displacement meter 81 is input to amplify the power, and the amplified power is sent to the moving mechanism 83. When the diameter is expanded and moved in the radial direction at the displacement meter 81, the moving mechanism 83 is operated by the same distance as the diameter expansion movement.
The moving mechanism 83 includes a positionable cylinder device, a ball screw mechanism, a cam mechanism, and the like. The moving mechanism 83 is interposed between the suspension mechanism 44 and both ends of the inductors 30a, 30b, and 30c so that the inductor 30 has a diameter. It is designed to move in the direction.

  In this case, when induction heating is performed and the support ring 23 expands due to thermal expansion, the expansion amount of the support ring 23 is detected by the displacement meter 81 at three locations, and the automatic control of the follow-up control circuit 82 based on the detected amount. Accordingly, the moving mechanism 83 operates to extend in the diameter expansion direction. At this time, since the extension amount of the moving mechanism 83 is more preferably equal to the diameter expansion amount detected by the displacement meter 81 at the corresponding position, the distance obtained by projecting the extension amount in the radial direction is equal to the inductor 30a, 30b, Both ends of 30c continue to face the support ring 23 at a constant distance.

In addition, the intermediate portions of the inductors 30a, 30b, and 30c are also moved in the diameter increasing direction of the support ring 23, so that the variation in the facing distance is suppressed to a slight amount. In addition, even when the support ring 23 is deformed into a non-circular shape, it is adapted to follow to some extent.
Note that one of the pair of moving mechanisms 83 connected to each of the inductors 30a, 30b, and 30c is connected to the suspension mechanism 44 or the inductor 30 with a hinge or the like, for example, and is inclined in the circumferential direction. If the movement mechanism 83 is operated in accordance with the diameter expansion of the support ring 23, the distance of the divided portion of the inductor 30 changes and the diameter of the inductor 30 increases. The inductor 30 is not deformed excessively.

[Others]
When securing the quenching apparatus 40 in the above-described embodiment, a structure in which a rotating mechanism for rotating the disk 46 is incorporated in the gantry 45 is adopted, and the rotating mechanism is operated during induction heating to thereby operate the disk 46. The upper metal turning wheel may be rotated. By rotating the annular inductor 30 and the metal turning wheel relative to each other while maintaining the facing state, undesired effects such as local variations in the facing distance caused by thermal deformation or the like are averaged in the circumferential direction. The gap between the conducting end 31 of the inductor 30a and the conducting end 32 of the inductor 30b, the gap between the conducting end 31 of the inductor 30b and the conducting end 32 of the inductor 30c, the conducting end 31 of the inductor 30c and the inductor 30a The influence of a slight spread of the induced current in the gap with the energization end 32 is also reduced.

About one embodiment of the present invention, a specific example of a metal swirl wheel is shown, (a) is a perspective view of the metal swirl wheel, (b) is a partially enlarged sectional view, (c) is a developed perspective view of the ring, (D) is the one part expanded sectional view. (A) is a partial cross-sectional enlarged view showing the retaining ring and its rolling contact surface, (b) is a partial cross-sectional enlarged view showing the nose ring and its rolling contact surface, and (c) is the support ring and its rolling contact surface. It is a partial cross section enlarged view which shows a dynamic contact surface. (A) is a perspective view of the inductor corresponding to the rolling contact surface located on the end face of the support ring (that is, a row of inductors arranged in an annular shape), (b) is a partially enlarged cross-sectional view of the inductor, c) is a longitudinal sectional view of the inductor and the support ring in the opposed state, and (d) is a partially enlarged view thereof. The structure of a hardening apparatus is shown, (a) is a front view, (b) is a left view. It is a block diagram of a high frequency power supply device. (A) is sectional drawing which shows the structural example of the cooling means of a heating surface, (b) is sectional drawing which shows the structural example of the cooling device of an opposite surface. It is a block diagram of a high frequency power unit about other embodiments of the present invention. (A) is the perspective view of the inductor corresponding to the rolling contact surface located in the internal peripheral surface of a support ring about other embodiment of this invention, (b) is the partial cross section enlarged view of the inductor, c) is a longitudinal sectional view of the inductor and the support ring in the opposed state, and (d) is a partially enlarged view thereof. In another embodiment of the present invention, (a) is a perspective view of inductors corresponding to rolling contact surfaces located on the outer peripheral surface of the nose ring (that is, a row of inductors arranged in an annular shape), and (b) is The partial cross-sectional enlarged view of an inductor, (c) is a longitudinal cross-sectional view of the inductor and nose ring of the opposing state, (d) is the partially expanded view. It is a partial cross section enlarged view which shows hardening by one-shot heating in order of a process. It is a partial cross section enlarged view which shows hardening by the one-shot heating with opposite surface cooling in order of a process. It is a top view of support ring 23 and inductor 30 which oppose, and diameter-expansion means 80 attached to it about other embodiments of the present invention. It is a perspective view which shows the hardening by the conventional width direction moving heating.

Explanation of symbols

10 ... Metal swivel wheel, 15 ... Soft zone,
20 ... Metal swivel wheel,
21 ... Retaining ring (outer ring), 21a ... Rolling contact surface (end surface),
22 ... Nose ring (inner ring), 22a ... Rolling contact surface (outer peripheral surface),
22b ... rolling contact surface (end surface), 22c ... opposite surface, 23 ... support ring (outer ring),
23a ... rolling contact surface (end surface), 23b ... rolling contact surface (inner peripheral surface),
24, 25, 26 ... Rollers
30 ... Inductors (a plurality of inductors, a row of inductors arranged in a ring),
30a, 30b, 30c ... inductor (a heating coil divided in three),
31, 32 ... energization end, 34 ... injection port (first cooling means), 35 ... cooling water (refrigerant),
40 ... quenching device,
41 ... Base unit, 42 ... Elevating mechanism (moving device),
43 ... Position adjustment mechanism, 44 ... Suspension mechanism, 45 ... Mount (rotation mechanism),
46 ... disk (rotary body), 46a ... water flow groove (second cooling means),
50. High frequency power supply,
51 ... AC source, 52 ... Rectification unit, 53 ... Inverter (orthogonal transformation unit),
54 ... Power supply circuit (primary side circuit), 55 ... Insulation transformer, 56 ... Secondary side circuit,
60 ... high frequency power supply,
63 ... Inverter (orthogonal transformation unit), 65 ... Insulation transformer, 68 ... In-phase control circuit,
70 ... Cooling device (second cooling means),
71 ... water supply pipe, 72 ... cooling water (refrigerant), 73 ... water supply pipe, 74 ... injection port,
80 ... Diameter expanding means,
81 ... Displacement meter, 82 ... Tracking control circuit, 83 ... Moving mechanism

Claims (9)

  In the quenching method for a metal swirl ring rolling contact surface that quenches the rolling contact surface of a metal swirl ring using induction heating, when performing the induction heating, a plurality of inductors are annularly opposed to the rolling contact surface. These inductors are subjected to high-frequency energization and heated to a great circle. At that time, a desired induced electromotive force is applied under the condition that a voltage of 600 V or less is applied to each of the inductors during the high-frequency energization. A method for quenching a rolling contact surface of a metal swivel wheel, wherein a numerical value of plural inductors is determined so as to be obtained.   The method and apparatus for quenching a metal swivel rolling contact surface according to claim 1, wherein in-phase currents are supplied from a plurality of power sources insulated from each other during the high-frequency energization.   In a quenching apparatus for a metal swirl ring rolling contact surface that quenches a rolling contact surface of a metal swirl ring using induction heating, a ring that supports the metal swirl wheel and is capable of facing the rolling contact surface. And a plurality of power supply devices that can control the phase of the output current, and a common-phase control circuit that makes the phases of the output currents the same. Hardening device for moving contact surface.   The method of quenching a metal swivel rolling contact surface according to claim 2, wherein the rolling contact surface is quenched while rotating the metal swirl wheel in a circumferential direction relative to the inductor.   4. The quenching apparatus for a rolling contact surface of a metal swivel wheel according to claim 3, further comprising a rotation mechanism for rotating the metal swivel wheel in a circumferential direction relative to the inductor.   5. The metal turning according to claim 2, wherein the rolling contact surface is quenched while a surface opposite to the surface facing the inductor in the metal turning wheel is cooled by a cooling device. A method of quenching the rolling contact surface.   6. The metal according to claim 3, further comprising a cooling device provided at a position facing the metal swivel ring from a side opposite to the inductor to simultaneously cool the metal swivel ring in a circumferential direction. Quenching device for rolling contact surface of swivel wheel.   When performing the induction heating, the inductor is moved in the diameter expansion direction following the diameter expansion of the metal swirl wheel due to thermal expansion. The quenching method of the metal turning wheel rolling contact surface described in any one of them.   4. A moving mechanism that moves the inductor in a radial direction of the metal swirl wheel, and a follow-up control unit that operates the moving mechanism in accordance with an increase in diameter of the metal swirl wheel. A quenching device for a rolling contact surface of a metal swivel wheel according to any one of claims 5 and 7.

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