JP2007172923A - Induction heating coil and brazing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction heating coil capable of uniformly heating the entire work by preventing the overheating of a slit gap. <P>SOLUTION: A conductive part 210 for the peripheral surface of a shell has a small conductive part 220 having four parallel conductive parts 221, 222, 223 and 224 extending in parallel with the radius direction (arrow R direction) of the shell 72, a small conductive part 230 having four parallel conductive parts 231, 232, 233 and 234 extending in parallel with the radius direction of the shell 72, a small conductive part 240 having four parallel conductive parts 241, 242, 243 and 244 extending in parallel with the radius direction of the shell 72, and a small conductive part 250 having four parallel conductive parts 251, 252, 253 and 254 extending in parallel with the radius direction of the shell 72. Each parallel conductive part 221, 222, ..., 253 and 254 may be in parallel with the radius direction of the shell 72, but each of them may not be exactly in parallel with the radius direction and may be placed side by side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an induction heating coil and a brazing device for brazing used when assembling a turbine runner or the like of a torque converter.

  A torque converter is known as a component that constitutes an automatic transmission mounted on a passenger car. The torque converter includes a turbine runner, a pump impeller, and the like. The turbine runner and the pump impeller are manufactured by brazing a plate-shaped shell and a ring-shaped inner core with a large number of plate-shaped blades. A large number of slits (elongated holes) are formed in a substantially radial direction on the shell and the inner core of the turbine runner, and protrusions inserted into the large number of slits are formed on the blade.

When brazing, blade protrusions are inserted into the slits of the shell and the inner core and bent, and the brazing material is disposed in the vicinity of the bent protrusions to heat the entire turbine runner. By this heating, the brazing material is melted and the projections are joined to the shell and the inner core, so that the blade is joined to the shell and the inner core. As a technique for heating the turbine runner during brazing, a technique using an induction heating coil extending in the circumferential direction of the shell is known (for example, see Patent Document 1).
JP 2005-254295 A

  A plurality of radially elongated slits are formed in the outer peripheral edge portion and the inner peripheral edge portion of the shell so as to be aligned in the radial direction of the shell at a predetermined interval. In this shell, a portion between slits adjacent to each other in the radial direction of the shell (a slit gap portion, a portion where current flows) is very narrow compared to a portion where no slit is formed. For this reason, when brazing a blade to such a shell, if an induction heating coil extending in the circumferential direction of the shell is used, an eddy current flowing in the circumferential direction is induced. Occurs. That is, an eddy current flows from a wide portion where no slit is formed into a slit gap portion (narrow portion), and the density of the eddy current rapidly increases in the slit gap portion. As a result, the slit gap portion is overheated (overheated), and the entire shell cannot be heated uniformly. In addition, when an induction heating coil extending in the circumferential direction of the shell is used, the eddy current is canceled at a location where the eddy currents flowing in the induction heating coil are close to each other in the opposite direction, and the incompletely heated portion (other locations) A lower temperature portion).

  In view of the above circumstances, an object of the present invention is to provide an induction heating coil and a brazing device that can prevent overheating (overheating) of a slit gap portion and generation of an incompletely heated portion and can uniformly heat the entire workpiece. To do.

In order to achieve the above object, an induction heating coil according to the present invention is an induction heating coil that induction-heats an object to be heated, in which a plurality of slits are arranged at predetermined intervals and arranged in a predetermined direction.
(1) An eddy current flowing in parallel in the predetermined direction is induced in the object to be heated.

here,
(2) The plurality of slits may extend in the predetermined direction.

further,
(3) The object to be heated may be bowl-shaped or disk-shaped with an opening formed in the center.

In addition, the induction heating coil of the present invention for achieving the above object is a bowl shape having an opening formed in the center, and a plurality of slits are formed at predetermined intervals on the outer peripheral edge and the inner peripheral edge. A shell and a ring disposed between an outer peripheral edge and an inner peripheral edge of the shell, and a slit facing the slit of the outer peripheral edge of the shell is formed in the outer peripheral edge. An inner core formed with slits on the inner peripheral edge of the inner peripheral edge of the shell, and an inner peripheral edge of both the shell and the inner core between the outer peripheral edges of the shell and the inner core. A blade of a turbine runner including a blade formed with a protrusion inserted into each of the slits and bent, and existing in a space extending between the shell and the inlet. In the induction heating coil for brazing in Koa,
(4) A shell outer peripheral surface conductive portion in which a small conductive portion having a plurality of parallel conductive portions extending in parallel with the radial direction of the shell faces the outer peripheral surface of the shell and is arranged side by side along the outer peripheral surface;
(5) An arcuate inner core conductive portion extending along the outer peripheral edge portion is provided above the outer peripheral edge portion of the inner core.

here,
(6) The plurality of small conductive portions may be an even number, and two adjacent small conductive portions may be manufactured by bending one conductive member.

further,
(7) An arcuate shell inner conductive portion extending along the inner peripheral edge may be provided above the inner peripheral edge of the shell.

Furthermore,
(8) Instead of the arc-shaped inner core conductive portion, a circular inner core conductive portion may be provided.

Furthermore,
(9) Instead of the arcuate shell inner conductive portion, a circular shell inner conductive portion may be provided.

Furthermore,
(10) The arcuate shell inner conductive portion or the circular shell inner conductive portion may be produced by bending a single conductive member.

Furthermore,
(11) The arc-shaped inner core conductive portion and the arc-shaped inner shell conductive portion may be produced by bending a single conductive member.

The brazing device of the present invention for achieving the above object is
(12) The projections of the blades inserted into the slits on the outer peripheral edge of the shell according to any one of the above are brazed to the outer peripheral edge with a brazing material having a predetermined shape, and A non-oxidizing atmosphere heating chamber in which the above-described induction heating coil is disposed, in which the protrusion of the blade inserted into the slit of the peripheral edge is brazed to the outer peripheral edge, is provided. is there.

here,
(13) A moving mechanism for moving the inner core conductive portion and / or the shell inner conductive portion may be provided.

further,
(14) The brazing material having the predetermined shape is made of a rod-shaped brazing material having a square or rectangular cross section, and brazing may be performed using this brazing material.

  Here, the term “parallel” includes not only a direction parallel to a predetermined direction but also a direction along the predetermined direction.

  When an object to be heated is induction-heated using the induction heating coil of the present invention, an eddy current flows in parallel in a predetermined direction in which a plurality of slits are arranged, so a portion between adjacent slits in the predetermined direction (slit gap portion) Therefore, eddy current contraction (a phenomenon in which current flows from a wide part to a narrow part and the current density rapidly rises) does not occur. Accordingly, overheating (overheating) due to the contracted flow does not occur in the slit gap portion. On the other hand, when an induction heating coil that induces eddy currents in a direction orthogonal (or substantially orthogonal) to a predetermined direction is used, eddy currents flow from a wide part to a narrow part of the object to be heated. Since the contraction occurs in the slit gap portion, the slit gap portion is overheated.

  In addition, when the object to be heated is induction-heated using the induction heating coil of the present invention, a location (low temperature region) in which the eddy current flows close to each other in the opposite direction is generated at the center of the heating coil. Since the eddy current flowing in parallel to the predetermined direction of the coil moves in the circumferential direction by the rotation of the object to be heated, the low temperature region at the center is eliminated and the incompletely heated portion (temperature unevenness) does not occur. On the other hand, when an induction heating coil that induces eddy currents in a direction (circumferential direction) orthogonal to a predetermined direction is used, eddy currents are generated at locations where eddy currents flowing in the induction heating coils flow in directions opposite to each other. It cancels out and produces a low temperature region in the circumferential direction. Even if the object to be heated is rotated, the low temperature region in the circumferential direction is not eliminated, and an incompletely heated portion having a low temperature is generated in the circumferential direction as compared with other portions.

  As a result, when the induction heating coil of the present invention is used, it can be heated uniformly over the entire object to be heated. Therefore, brazing can be realized even for parts having slits and holes such as a turbine runner.

  The present invention has been realized in brazing when producing a turbine runner.

  An example of the brazing apparatus of the present invention will be described with reference to FIG.

  FIG. 1 is a plan view showing a schematic configuration of a brazing apparatus provided with the induction heating coil of the present invention.

  The brazing apparatus 10 includes a conveyance roller 20 that conveys a turbine runner 70 (an example of an object to be heated according to the present invention) placed on a jig 120 (see FIG. 2) in the direction of arrow A, and a non-oxidizing atmosphere. (Non-oxidizing atmosphere) inlet side preliminary chamber 30, a heating chamber (brazing chamber) 40 for heating the turbine runner 70 to a predetermined temperature to melt and braze the brazing material, and the turbine runner 70 for which brazing has been completed A cooling chamber 50 for cooling the air and an outlet side preliminary chamber 60 in a non-oxidizing atmosphere. The turbine runner 70 is transported while being placed on the jig 120 until it is placed on the transport roller 20 and discharged from the cooling chamber 50.

  The turbine runner 70 placed on the jig 120 placed on the transport roller 20 is transported on the transport roller 20 in the direction of arrow A by pushing the jig 120 with the pusher 22. When the jigs 120 are pushed one by one by the pushers 24 and 26, they are accommodated in the entrance side preliminary chamber 30 in which the shutter 32-1 is opened. The inlet side preliminary chamber 30 is replaced with a non-oxidizing atmosphere each time the turbine runner is accommodated. The entrance side preliminary chamber 30 is separated from the heating chamber 40 by a shutter 32-2. The jig 120 pushed by the pusher 34 is transferred from the inlet side preliminary chamber 30 to the heating chamber 40 together with the turbine runner 70. The turbine runner 70 conveyed to the heating chamber 40 is moved together with the jig 120 from the position indicated by the two-dot chain line to the position indicated by the solid line, and is heated to a temperature required for brazing by the induction heating coil 200. The heating chamber 40 is maintained in a non-oxidizing atmosphere such as a nitrogen atmosphere. The turbine runner 70 is uniformly heated and the brazing materials 100 and 110 (see FIG. 3 and the like) are completely melted to perform brazing. Is done. Details of the induction heating coil 200 will be described later.

  The jig 120 on which the brazed turbine runner 70 is placed is pushed by the pusher 42, passes through the opened shutter 32-3, and is conveyed to the cooling chamber 50. In the cooling chamber 50, the turbine runner 70 is cooled to a predetermined temperature of 200 ° C. After this cooling, the turbine runner 70 is discharged by the pusher 52 through the opened shutter 32-4 into the outlet side preliminary chamber 60. The turbine runner 70 placed on the jig 120 is discharged from the outlet side preliminary chamber 60 with a pusher or the like (not shown), and the brazing operation is completed. The brazed turbine runner 70 is removed by a transfer device (not shown). On the other hand, the turbine runner 70 on which a new brazing material is set is placed on the jig 120, and the above brazing is repeated.

  The turbine runner 70 and the brazing materials 100 and 110 produced by brazing will be described with reference to FIGS.

  FIG. 2 is a perspective view showing a turbine runner to be brazed. 3 is a cross-sectional view taken along line XX in FIG. FIG. 4 is a plan view showing the blade. FIG. 5 is an enlarged plan view showing a part of the shell in which the contraction occurs. FIG. 6 is an enlarged plan view showing a part of the shell without contracted flow. FIG. 7 is a plan view showing two types of brazing materials.

  The turbine runner 70 includes a bowl-shaped shell 72 having an opening 72 a formed in the center, a ring-shaped inner core 74 disposed between the outer peripheral edge 72 b and the inner peripheral edge 72 c of the shell 72, and the shell 72. A plurality of blades 76 that extend in a space between the outer peripheral edge portion 72b of the inner core 74 and the inner peripheral edge portion 74c of the inner core 74 and the inner peripheral edge portion 74c of the inner core 74. It has. In FIG. 2, a part of the jig 120 on which the turbine runner 70 is placed protrudes from the opening 72 a (see FIG. 3) of the shell 72. In FIG. 3, the jig 120 is not shown.

  As shown in FIGS. 5 and 6, a plurality of slits 72bs1 are formed in the outer peripheral edge 72b of the shell 72 at equal intervals in the circumferential direction (arrow B direction). A plurality of slits 72bs2 are formed in the circumferential direction by being equally divided with the plurality of slits 72bs1 on the side of the center C slightly from the plurality of slits 72bs1. Similarly, a plurality of slits 72cs1 are formed on the inner peripheral edge 72c of the shell 72 in an equal division with the plurality of slits 72bs1 in the circumferential direction (arrow B direction). A plurality of slits 72cs2 are formed in the circumferential direction by being equally divided with the plurality of slits 72cs1 on the outer side (the side opposite to the center C) slightly from the plurality of slits 72cs1. Each of the slits 72bs1, 72bs2, 72cs1, 72cs2 has a thin rectangular shape extending in parallel in the radial direction (arrow R direction). In addition, each of the slits 72bs1, slit 72bs2, slit 72cs1, and slit 72cs2 arranged in the radial direction is arranged in a curved direction with respect to the radial direction, and is arranged in a direction parallel to the radial direction. It becomes.

  A projection 76a of the blade 76 is inserted into the slit 72bs1 of the shell 72 and bent, and a projection 76e of the blade 76 is inserted into the slit 72bs2 and bent. Further, the projection 76b of the blade 76 is inserted into the slit 72cs1 of the shell 72 and bent, and the projection 76f of the blade 76 is inserted into the slit 72cs2 of the shell 72 and bent. The number of the plurality of slits 72bs1, 72bs2, 72cs1, 72cs2 is the same as the number (number of sheets) of the blades 76. As shown in FIG. 3, the shell 72 is formed with a ring-shaped (annular) bottom portion 72d that is smoothly lowered from the outer peripheral edge portion 72b and lower than the outer peripheral edge portion 72b. A portion of the bottom portion 72d opposite to the outer peripheral edge portion 72b is higher than the lowest portion of the bottom portion 72d, and forms an inner peripheral edge portion 72c. A portion surrounded by the inner peripheral edge portion 72c (a portion inside the inner peripheral edge portion 72c) is an opening 72a.

  A slit 74bs is formed in a portion of the outer peripheral edge portion 74b of the inner core 74 facing the slits 72bs1 of the shell 72. Similarly, a slit 74cs is formed in a portion of the inner peripheral edge 74c of the inner core 74 facing the slits 72cs1 of the shell 72. The protrusion 76c of the blade 76 is inserted into the slit 74bs of the inner core 74 and bent, and the protrusion 76d of the blade 76 is inserted into the slit 74cs of the inner core 74 and bent. The number of the plurality of slits 74bs is the same as the number (number of sheets) of the blades 76, and the number of the plurality of slits 74cs is also the same as the number (number of sheets) of the blades 76. As shown in FIG. 3, the inner core 74 is located above the bottom 72 d of the shell 72 and is connected to the shell 72 via a blade 76. The inner core 74 is disposed at a position where it is placed on the blade 76. Further, the inner core 74 is disposed at a position slightly lower than the outer peripheral edge portion 72b of the shell 72 and slightly higher than the inner peripheral edge portion 72c.

  As described above, the blade 76 is formed with protrusions 76a, 76e, 76b, 76f, 76c, and 76d that are inserted and bent corresponding to the slits 72bs1, 72bs2, 72cs1, 72cs2, 74bs, and 74cs, respectively. Further, the blade 76 has the projections 76a, 76e, 76b, 76f, 76c, and 76d inserted into the slits 72bs1, 72bs2, 72cs1, 72cs2, 74bs, and 74cs, respectively, so that the outer peripheral edge 72b, the inner peripheral edge 72c, In the state of rising from the bottom 72d and along the outer peripheral edge 72b of the shell 72 (along the inner peripheral edge 72c or the outer peripheral edge 74b and inner peripheral edge 74c of the inner core 74) ). The blade 76 is present in a space that is sandwiched between the shell 72 and the inner core 74.

  The protrusions 76a, 76e, 76b, and 76f inserted and bent into the slits 72bs1, 72bs2, 72cs1, and 72cs2 of the shell 72 are joined to the outer peripheral surface 72e of the shell 72 by the brazing material 100 shown in FIG. Further, the projections 76c and 76d inserted and bent into the slits 74bs and 74cs of the inner core 74 are joined to the inner peripheral surface (upper surface) 74d of the inner core 74 by the brazing material 110 shown in FIG.

  As shown in FIG. 7, the brazing materials 100 and 110 are V-shaped or U-shaped (not shown) manufactured from rod-shaped copper (or copper alloy) having a cross section of a square S1 or a rectangle S2. The legs 100a and 110a have a length corresponding to the amount of brazing necessary for the brazed portion. In continuous atmosphere brazing by resistance heating, the object to be heated and the brazing material are each radiantly heated in a brazing furnace. However, in induction heating brazing, a non-magnetic brazing material such as copper brazing is not induction-heated but is heated by heat conduction and radiation of the object to be heated that has been induction-heated. For this reason, if a brazing material with a circular cross-section, which is normally used for resistance heating brazing, is in a point (line) contact with the object to be heated, it is difficult to conduct heat conduction, causing insolubilization, overheating of the object to be heated. Problems occur. In the brazing material whose surface is in contact with the object to be heated such that the cross section is square or rectangular, the above problem can be solved, and the quality of the brazed part can be improved.

  A brazing method for brazing the shell 72, the inner core 74, and the blade 76 will be described.

  When brazing, first, as shown in FIGS. 2 and 3, the brazing material 100 is disposed in a portion of the blade 76 close to the outer peripheral edge portion 72 b of the shell 72 and formed on the outer peripheral edge portion 74 b of the inner core 74. The brazing material 110 is disposed in the vicinity of the slit 74bs. When the shell 72, the inner core 74, and the blade 76 are brazed with the brazing materials 100, 110 in the heating device 40 (see FIG. 1), the slits 72bs1 formed in the outer peripheral edge 72b of the shell 72 as described above. The brazing material 100 is disposed in the vicinity, and the brazing material 110 is disposed in the vicinity of the slits 74 bs formed in the outer peripheral edge portion 74 b of the inner core 74. No brazing material is disposed in the vicinity of the slits 72bs2, 72cs1, 72cs2 of the shell 72 and in the vicinity of the slit 74cs formed in the inner peripheral edge 74c of the inner core 74.

  By heating the turbine runner 70 and the brazing materials 100, 110 to a predetermined temperature in the heating device 40, the brazing materials 100, 110 are melted, and the projections 76a that are inserted into the slits 72bs1 and bent are formed on the outer peripheral edge 72b by the brazing material 100. At the same time, the protrusion 76 c that is inserted and bent into the slit 74 bs of the inner core 74 is joined to the outer peripheral edge 74 b by the brazing material 110. On the other hand, in the slits 72bs2, 72cs1, and 72cs2 of the shell 72 where the brazing material is not disposed, the brazing material 100 melted at the outer peripheral edge portion 72b flows through the gap and the boundary between the shell 72 and the blade 76 by capillarity. For this reason, the projections 76e, 76b, and 76f inserted and bent into the slits 72bs2, 72cs1, and 72cs2 are joined to the shell 72 by the brazing material 100. The brazing material 100 has a large amount (length) in order to join not only the protrusion 76 a but also the protrusions 76 e, 76 b and 76 f to the shell 72. Also, the brazing material 110 melted at the outer peripheral edge portion 74b flows into the slit 74cs of the inner peripheral edge portion 74c of the inner core 74 where the brazing material is not disposed, by the capillary phenomenon through the gap between the inner core 74 and the blade 76. . For this reason, the protrusion 76d that is inserted into the slit 74cs and bent is joined to the inner peripheral edge 74c by the brazing material 110. The brazing material 110 has a length necessary for joining not only the protrusion 76c but also the protrusion 76d. Note that the lengths of the brazing materials 100 and 110, for example, 100a and 110a, are determined according to the brazing length, such as the gap between the parts to be brazed.

  The brazing induction heating coil 200 will be described with reference to FIGS.

  FIG. 8 is a plan view showing an induction heating coil (inner core side) for brazing. FIG. 9 is a side view showing the entire induction heating coil, and shows a cross section of the turbine runner 70. FIG. 10 is a bottom view showing the induction heating coil (shell side) of FIG. FIG. 11 is a side view schematically showing a moving mechanism for moving the induction heating coil. 12 is a side view showing the induction heating coil rotated and moved by the moving mechanism of FIG. The broken line shown in FIG. 10 shows an example of the direction of alternating current.

  The induction heating coil 200 for brazing is disposed in the heating chamber 40 (see FIG. 1) as shown in FIG. The induction heating coil 200 includes a shell outer peripheral surface conductive portion 210 disposed to face the outer peripheral surface 72e of the shell 72, an arc-shaped inner core conductive portion 260 extending along the outer peripheral edge portion 74b of the inner core 74, And an arcuate inner shell conductive portion 270 extending along the inner peripheral edge 72 c of the shell 72.

  The shell outer peripheral surface conductive portion 210 includes a small conductive portion 220 having four parallel conductive portions 221, 222, 223, and 224 extending in parallel to the radial direction (arrow R direction) of the shell 72, and the radial direction of the shell 72. Small conductive part 230 having four parallel conductive parts 231, 232, 233, 234 extending in parallel and small conductive part having four parallel conductive parts 241, 242, 243, 244 extending in parallel to the radial direction of the shell 72 And a small conductive portion 250 having four parallel conductive portions 251, 252, 253, and 254 that extend in parallel to the radial direction of the shell 72. Each of the parallel conductive portions 221, 222,... 253, 254 may be parallel to the radial direction of the shell 72, but may be parallel to each other without being exactly parallel. In other words, an eddy current parallel to the radial direction (or this radial direction) is induced in the shell 72 by the alternating current flowing through the parallel conductive portions 221, 222. The effect of this eddy current will be described later with reference to FIG.

  Each of the four small conductive portions 220, 230, 240, and 250 has a substantially elliptical shape having parallel conductive portions extending in parallel in the radial direction, in other words, a slightly flat (crushed) spiral shape. is there. The four small conductive parts 220, 230, 240, 250 are connected to one AC power supply 212. The small conductive portion 220 and the small conductive portion 230 are electrically connected by the connection conductive portion 225. The small conductive portion 240 and the small conductive portion 250 are electrically connected by the connection conductive portion 245. One end portion in the longitudinal direction of the parallel conductive portion 223 is connected to the AC power supply 212, and the other end portion in the longitudinal direction is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 222. The other end portion in the longitudinal direction of the parallel conductive portion 222 is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 224. The other end in the longitudinal direction of the parallel conductive portion 224 is slightly curved and is connected to one end in the longitudinal direction of the parallel conductive portion 221. The other end portion in the longitudinal direction of the parallel conductive portion 221 is greatly curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 224. The parallel conductive portions 231, 232, 233, and 234 of the small conductive portion 230 are also electrically connected in the same manner as the parallel conductive portions 221, 222, 223, and 224. Such connection is the same for the small conductive portions 240 and 250. The four small conductive portions 220, 230, 240, and 250 are curved along the outer peripheral surface 72e of the shell 72 (see FIG. 9), and when the shell 72 is induction-heated, the optimum distance for this induction heating is obtained. Four small conductive parts 220, 230, 240, 250 are located.

  The effects of the eddy currents flowing in parallel (or in the radial direction) in the radial direction by the alternating currents flowing through the parallel conductive portions 221, 222... 253, 254 will be described with reference to FIGS. To do.

  The broken-line arrow H shown in FIG. 5 indicates the flow of eddy current when the shell 72 is heated by an induction heating coil (conventional induction heating coil) extending in the circumferential direction (arrow B direction) of the shell 72. Since this eddy current is an alternating current, it also flows in the direction opposite to the arrow H. 6 indicates the flow of eddy current when the shell 72 is heated by the shell outer peripheral surface conductive portion 210 of the induction heating coil 200 of the present invention, and this eddy current is AC current. Therefore, it flows in the direction opposite to the arrow P.

  Eddy currents induced in the shell 72 flow in the circumferential direction when the shell 72 is heated by an induction heating coil (conventional induction heating coil) extending in the circumferential direction of the shell 72. For this reason, in the portion of the shell 72 between the slits 72bs1 and 72bs2 (slit gap portion Y) aligned in the radial direction (arrow R direction) and the portion between the slit 72bs1 and the outer peripheral edge of the shell 72. As shown by the arrow H in FIG. 5, a phenomenon (constriction) in which the eddy current flows from the wide part of the shell 72 to the narrow part and the current density rapidly increases occurs. For this reason, the slit gap portion Y is heated to a higher temperature than the other portions of the shell 72 (overheated). As a result, the shell 72 is not heated uniformly throughout it (non-uniformly heated).

  On the other hand, the eddy current generated by the shell outer peripheral surface conductive portion 210 of the induction heating coil 200 of the present invention flows in the radial direction (or parallel to the radial direction) as shown by the arrow P in FIG. There is no flow. Such a contraction preventing effect is the same for the slits 72cs1 and 72cs2.

  In addition, this eddy current flowing in the radial direction (or in a direction parallel to the radial direction) moves in the circumferential direction because the object to be heated rotates, so that the eddy current flows close to each other in the opposite direction. The low temperature region generated in the central part of the heating coil is eliminated because the eddy current flowing in parallel to the predetermined direction of the outer coil of the heating coil moves in the circumferential direction due to the rotation of the object to be heated. Does not occur. As a result, the shell 72 is uniformly heated throughout.

  The inner core conductive portion 260 has an arc shape (semicircle) extending above the outer peripheral edge 74b of the inner core 74, and heats the brazing material 110 (see FIG. 2 and the like) disposed on the outer peripheral edge 74b. Melt. The shell inner conductive portion 270 has an arc shape (semicircular shape) extending above the inner peripheral edge 72c of the shell 72, and mainly heats the inner peripheral edge 72c. The inner core conductive portion 260 and the shell inner conductive portion 270 are produced by bending one conductive material. The central portion of the arc portion of the inner core conductive portion 260 is connected to the AC power supply 212. The inner core conductive portion 260 and the shell inner conductive portion 270 are positioned at an optimum distance for the induction heating when the inner core 74 and the shell 72 are induction heated.

  The inner core 74 is disposed at a position lower than the outer peripheral edge 72b of the shell 72 as shown in FIG. When the inner core conductive portion 260 is disposed at the same height as the outer peripheral edge portion 72 b of the shell 72, the inner core 74 is connected by the inner core conductive portion 260 because the distance between the inner core 74 and the inner core conductive portion 260 is large. It cannot be heated to the required brazing temperature. Further, when the inner core conductive portion 260 is disposed at a position lower than the outer peripheral edge portion 72 b of the shell 72, the horizontal movement of the inner core conductive portion 260 is obstructed by the outer peripheral edge portion 72 b of the shell 72, and the turbine runner 70 is transported. Can not be. Similarly, the shell inner conductive portion 270 disposed at a position lower than the outer peripheral edge 72 b of the shell 72 also inhibits the conveyance of the turbine runner 70.

  The inner core conductive portion 260 and the shell inner conductive portion 270 are moved by the moving mechanism 300 in order to heat the inner core 74 and the inner peripheral edge 72 c of the shell 72 and to enable the conveyance of the turbine runner 70. As shown in FIGS. 11 and 12, the moving mechanism 300 is attached to a base 302 to which the shell outer peripheral surface conductive portion 210 is fixed. When the base 302 is viewed from the side, it is L-shaped, and a vertical member 304 rising from the bottom wall 44 of the heating chamber 40 (see FIG. 1), and a parallel member 306 extending in parallel from the top of the vertical member 304 It has. The parallel member 306 is also a lead electrically connected to the induction heating coil 200.

  The vertical movement shaft 310 of the moving mechanism 300 is attached to the vertical member 304 of the base 302 so as to be movable up and down (movable in the direction of arrow F). The vertical movement shaft 310 extends in the vertical direction (arrow F direction), and the upper end portion is connected to the rod 352 of the cylinder 350 of the moving mechanism 300. Therefore, when the cylinder 350 is turned on and off, the vertical movement shaft 310 moves up and down. When the cylinder 350 is on, the vertical movement shaft 310 rises to the uppermost position and stops. When the cylinder 350 is off, the vertical movement shaft 310 The shaft 310 descends to the lowest position and stops.

  A long hole 310 a is formed at the lower end of the vertical movement shaft 310. A projection 322 is movably fitted in the elongated hole 310a. The protrusion 322 is fixed to the lower portion of the swing arm 320 that is rotatably fixed to the parallel member 306 of the base 302. The swing arm 320 is fixed to a rotation shaft 306 a that is rotatably fixed to the parallel member 306. In addition, one end of the inner core conductive portion 260 is fixed to an upper portion of the swing arm 320 on the side opposite to the position of the rotation shaft 306a.

  When the cylinder 350 is off, as shown in FIG. 11, the vertical movement shaft 310 is lowered to the lowest position and stopped, and the weight of the inner core conductive portion 260 and the inner shell conductive portion 270 and the swing arm are stopped. The inner core conductive portion 260 and the shell inner conductive portion 270 are located at the heating position (position shown in FIG. 11) due to the weight of 320 or the like. In this case, the protrusion 322 is located at the upper part of the long hole 310a. When the turbine runner 70 is heated, the inner core conductive portion 260 and the shell inner conductive portion 270 are positioned at the heating position and energized.

  When the turbine runner 70 is mounted so as to be heated by the induction heating coil 200, the cylinder 350 is turned on and the swing arm 320 is rotated about the rotation shaft 306a to the position (mounting position) shown in FIG. . By this rotation, the inner core conductive portion 260 and the shell inner conductive portion 270 are positioned at the mounting position shown in FIG. 12, and the turbine runner 70 is conveyed in the direction of arrow E for each jig 120. After the turbine runner 70 and the jig 120 are positioned at the mounting position, the cylinder 350 is turned off and the induction heating coil 200 is positioned at the heating position as shown in FIG. After the heating chamber is replaced with a non-oxidizing atmosphere, an alternating current is supplied to the induction heating coil 200 while slowly rotating the turbine runner 70 together with the jig 120, and the turbine runner 70 is induction-heated to perform brazing.

  The induction heating coil 200 is configured such that cooling water flows therein, and the cooling water is discharged to the outside of the heating chamber 40 via the swing arm 320 and the parallel member 306.

  The moving mechanism 300 for the inner core conductive portion 260 and the shell inner conductive portion 270 has a heating portion at a position lower than the inner peripheral edge of the inner core and shell of the pump impeller having the same configuration, and other outer peripheral portions. Applicable for heating parts.

  Another example of the shell outer peripheral surface conductive portion 210 of the induction heating coil 200 will be described with reference to FIGS. 13 to 15.

  FIG. 13 is a plan view showing a shell outer peripheral surface conductive portion including a pair of small conductive portions. FIG. 14 is a plan view showing a shell outer peripheral surface conductive portion including one small conductive portion. FIG. 15 is a plan view showing the whole shell-shaped conductive portion for the outer peripheral surface of the fan. In these drawings, the same components as those shown in FIG. 10 are denoted by the same reference numerals.

  The shell outer peripheral surface conductive portion 410 shown in FIG. 13 includes a small conductive portion 420 having four parallel conductive portions 421, 422, 423, and 424 extending in parallel with the radial direction of the shell 72 (in the direction of arrow R), and the shell 72. A small conductive portion 430 having four parallel conductive portions 431, 432, 433, and 434 extending in parallel in the radial direction. Each of the parallel conductive portions 421, 422... 433, 434 may be parallel to the radial direction of the shell 72. However, the parallel conductive portions 421, 422. In other words, an eddy current parallel to the radial direction (or this radial direction) is induced in the shell 72 by the alternating current flowing through the parallel conductive portions 421, 422 ...... 433, 434.

Each of the two small conductive portions 420 and 430 has a substantially elliptical shape having parallel conductive portions extending in parallel in the radial direction. In other words, the two small conductive portions 420 and 430 have a slightly flat spiral shape. The two small conductive parts 420 and 430 are connected to one AC power supply 212. The small conductive portion 420 and the small conductive portion 430 are electrically connected by a connection conductive portion 425.
One end portion in the longitudinal direction of the parallel conductive portion 423 is connected to the AC power supply 212, and the other end portion in the longitudinal direction is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 422. The other end portion in the longitudinal direction of the parallel conductive portion 422 is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 424. The other end portion in the longitudinal direction of the parallel conductive portion 424 is slightly curved and is connected to one end portion in the longitudinal direction of the parallel conductive portion 421. The other end portion in the longitudinal direction of the parallel conductive portion 421 is greatly curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 434. The parallel conductive portions 431, 432, 433, and 434 of the small conductive portion 430 are also electrically connected in the same manner as the parallel conductive portions 421, 422, 423, and 424. The two small conductive portions 420 and 430 are curved along the outer peripheral surface of the shell 72, and when the shell 72 is induction-heated, the two small conductive portions 420 and 430 are positioned at an optimum distance for the induction heating. To do.

  The shell outer peripheral surface conductive portion 210 described in the embodiment is obtained by arranging two of the shell outer peripheral surface conductive portions 410 electrically in parallel and physically in a semicircular shape.

  A shell outer peripheral surface conductive portion 510 shown in FIG. 14 includes a small conductive portion 520 having four parallel conductive portions 521, 522, 523, and 524 that extend in parallel in the radial direction (arrow R direction) of the shell 72. . The parallel conductive portions 521, 522, 523, and 524 may be parallel to the radial direction of the shell 72, but may be parallel but not exactly parallel. In other words, an eddy current parallel to the radial direction (or this radial direction) is induced in the shell 72 by the alternating current flowing through each parallel conductive portion 521, 522, 523, 524.

  One small conductive portion 520 has a substantially elliptical shape (substantially elliptical shape) having a long axis extending in parallel with the radial direction, in other words, a slightly flat (squeezed) spiral shape. One small conductive portion 520 is connected to one AC power supply 212. One end portion in the longitudinal direction of the parallel conductive portion 523 is connected to the AC power supply 212, and the other end portion in the longitudinal direction is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 522. The other end in the longitudinal direction of the parallel conductive portion 522 is curved and connected to one end in the longitudinal direction of the parallel conductive portion 524. The other end in the longitudinal direction of the parallel conductive portion 524 is slightly curved and is connected to one end in the longitudinal direction of the parallel conductive portion 521. One small conductive portion 520 is curved along the outer peripheral surface of the shell 72, and when the shell 72 is induction-heated, the one small conductive portion 520 is located at an optimum distance for this induction heating.

  The shell outer peripheral surface conductive portion 410 is formed by electrically arranging two shell outer peripheral surface conductive portions 510 in series.

  A shell outer peripheral surface conductive portion 610 shown in FIG. 15 includes a small conductive portion 620 having four parallel conductive portions 621, 622, 623, 624 extending in the radial direction (arrow R direction) of the shell 72. Each parallel conductive portion 621, 622, 623, 624 may be in the radial direction of the shell 72, but not necessarily in the radial direction. In other words, an eddy current is induced in the shell 72 in the radial direction by an alternating current flowing through each parallel conductive portion 621, 622, 623, 624.

  The small conductive portion 620 has a fan shape as a whole, and has a shape that spreads with the center C as the main point of the fan. One small conductive part 520 is connected to one AC power supply 212. One end portion in the longitudinal direction of the parallel conductive portion 623 is connected to the AC power supply 212, and the other end portion in the longitudinal direction is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 622. The other end portion in the longitudinal direction of the parallel conductive portion 622 is curved and connected to one end portion in the longitudinal direction of the parallel conductive portion 624. The other end in the longitudinal direction of the parallel conductive portion 624 is slightly curved and is connected to one end in the longitudinal direction of the parallel conductive portion 621. One small conductive portion 620 is curved along the outer peripheral surface of the shell 72, and when the shell 72 is induction-heated, the one small conductive portion 620 is located at an optimum distance for this induction heating.

  Since the small conductive portion 620 of the shell outer peripheral surface conductive portion 610 can be physically arranged more densely than the small conductive portion 520 of the shell outer peripheral surface conductive portion 510, it can be heated quickly.

  As described above, it is possible to uniformly heat the object to be heated by appropriately combining the small conductive portions electrically and physically.

It is a top view which shows schematic structure of the brazing apparatus provided with the induction heating coil of this invention. It is a perspective view which shows the turbine runner brazed. FIG. 3 is a sectional view taken along line XX in FIG. 2. It is a top view which shows a braid | blade. It is a top view which expands and shows a part of shell which the contracted flow produced. It is a top view which expands and shows a part of shell without a contracted flow. It is a top view which shows two types of brazing materials. It is a top view which shows the induction heating coil (inner core side) for brazing. It is a side view which shows the whole induction heating coil, and the turbine runner 70 has shown the cross section. It is a bottom view which shows the induction heating coil (shell side) of FIG. It is a side view which shows typically the moving mechanism which moves an induction heating coil. It is a side view which shows the induction heating coil moved by the moving mechanism of FIG. It is a top view which shows the electroconductive part for shell outer peripheral surfaces which consists of a pair of small electroconductive part. It is a top view which shows the electroconductive part for shell outer peripheral surfaces which consists of one small electroconductive part. It is a top view which shows the electroconductive part for shell outer peripheral surfaces which consists of one small electroconductive part of the whole fan shape.

Explanation of symbols

10 Brazing device 40 Heating chamber (brazing chamber)
70 Turbine runner 72 Shell 72bs1, 72bs2, 72cs1, 72cs2, 74bs, 74cs Slit 74 Inner core 76 Blade 200 Induction heating coil 210 Shell outer peripheral surface conductive portions 220, 230, 240, 250 Small conductive portions 221, 222, 223, 224 , 231,232,233,234,241,242,243,244,251,252,253,254, parallel conductive portion 260 inner core conductive portion 270 shell inner conductive portion 300 moving mechanism

Claims (13)

In an induction heating coil that induction-heats an object to be heated formed with a plurality of slits arranged in a predetermined direction at a predetermined interval,
An induction heating coil that induces eddy currents flowing in parallel in the predetermined direction to the object to be heated. The induction heating coil according to claim 1, wherein the plurality of slits extend in the predetermined direction. 3. The induction heating coil according to claim 1, wherein the object to be heated is a bowl-shaped or disk-shaped object having an opening formed in a central portion thereof. A bowl having an opening formed at the center, and a shell having a plurality of slits formed at a predetermined interval between the outer peripheral edge and the inner peripheral edge, and between the outer peripheral edge and the inner peripheral edge of the shell. A ring-shaped one arranged, wherein a slit facing the outer peripheral edge slit of the shell is formed in the outer peripheral edge, and a slit facing the inner peripheral edge slit of the shell is the inner peripheral edge And the inner core formed between the outer peripheral edge of both the shell and the inner core and the space between the inner peripheral edge of both the shell and the inner core. In an induction heating coil for brazing the blade of a turbine runner comprising a blade formed with a protrusion that is bent in a bent manner to the shell and the inner core,
A small conductive portion having a plurality of parallel conductive portions extending in parallel to the radial direction of the shell faces the outer peripheral surface of the shell and is arranged side by side along the outer peripheral surface;
An induction heating coil comprising: an arcuate inner core conductive portion extending along the outer peripheral edge portion above the outer peripheral edge portion of the inner core. The induction heating coil according to claim 4, wherein the plurality of small conductive portions are an even number, and two adjacent small conductive portions are formed by bending one conductive member. The induction heating coil according to claim 4 or 5, further comprising an arc-shaped inner shell conductive portion extending along the inner peripheral edge above the inner peripheral edge of the shell. The induction heating coil according to claim 4, 5 or 6, further comprising a circular inner core conductive portion instead of the arc-shaped inner core conductive portion. 8. The induction heating coil according to claim 6, wherein a circular shell inner conductive portion is provided instead of the arc-shaped shell inner conductive portion. 9. The induction heating coil according to claim 6, wherein the arc-shaped inner shell conductive portion or the circular shell inner conductive portion is formed by bending a single conductive member. The induction heating coil according to claim 6, wherein the arc-shaped inner core conductive portion and the arc-shaped shell inner conductive portion are formed by bending one conductive member. The projection of the blade inserted into the slit of the outer peripheral edge of the shell according to any one of claims 4 to 10, is brazed to the outer peripheral edge with a brazing material having a predetermined shape, and The induction heating coil according to any one of claims 4 to 10, wherein the protrusion of the blade inserted into a slit in the outer peripheral edge of the inner core is brazed to the outer peripheral edge. A brazing device comprising a non-oxidizing atmosphere heating chamber. The brazing device according to claim 11, further comprising a moving mechanism that moves the inner core conductive portion and / or the shell inner conductive portion. 13. The brazing material having a predetermined shape is made of a rod-shaped brazing material having a square or rectangular cross section, and brazing is performed using the brazing material. Brazing equipment.

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