JP2008169923A - Tempering method of outer ring of constant velocity universal joint, and induction heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tempering method of an outer ring of a constant velocity universal joint capable of tempering the outer ring to uniform hardness in a short time. <P>SOLUTION: This tempering method includes: a process of axially inserting a mouth 2 into a ring-like coil 5 composed by arranging, in the circumferential direction, a plurality of unit windings 10 wound along a plane including an axis line, and arranging outer surfaces thereof corresponding to guide grooves 4 of the mouth 2 to face magnetic flux shielding members 9 arranged in the ring-like coil 5, and formed of a magnetic material; a process of making a current flow to the ring-like coil 5 to axially generate an induction current in the mouth 2, and carrying out induction heating for a predetermined period; and a process of cooling the induction-heated mouth 2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for tempering a constant velocity universal joint outer ring by induction heating and tempering a hardened layer formed by quenching an outer ring of a constant velocity universal joint, and an induction heating apparatus used for the method.

  For example, on the outer ring of a constant velocity universal joint for automobiles, a stem portion in which an axial guide groove for guiding a torque transmission member is formed on the inner peripheral surface and a tooth portion portion such as serration on the outer peripheral surface is formed. Some parts are integrally formed. A hardened layer by quenching and tempering is formed on the inner peripheral surface of the mouse portion and the outer peripheral surface of the stem portion, thereby improving the mechanical strength and ensuring the fatigue life.

A conventional method of tempering the outer ring of the constant velocity universal joint will be described with reference to FIG. First, the outer ring 101 integrally having the mouse portion 104 and the stem portion 105 is supported by the upper and lower jigs 102 and 103 and inserted into the cylindrical coil 100 in the axial direction. And the high frequency current was sent through the coil 100, the outer ring | wheel 101 was induction-heated for the predetermined time, and it cooled and tempered after that (for example, refer patent document 1).
Japanese Patent Laid-Open No. 5-9584

  FIG. 5 is a cross-sectional view of FIG. 4, and the hatched portion in FIG. 5 indicates a hardened layer formed by quenching formed on the inner peripheral surface of the mouse portion 104. As shown in the figure, since the guide groove 106 is formed on the inner peripheral surface of the mouse portion 104, for example, the A portion corresponding to the bottom portion of the guide groove 106 is more coiled than the inner surface other than the bottom portion, for example, the B portion. Since it is at a position close to 100, the temperature rises when induction heating is performed.

  Moreover, generally in the part (A part and B part) hardened by quenching, when the heating time is the same, the amount of decrease in hardness tends to increase as the heating temperature increases. That is, since the hardness of the A part that is easy to raise is lower than that of the B part that is difficult to raise, the heating of the A part must be suppressed to a temperature at which the specified hardness can be maintained.

  However, when the outer ring is tempered by the conventional method, as shown in the graph of FIG. 6, when the portion B, which is difficult to increase in temperature, is heated for a predetermined time (α) until reaching the temperature (T1) necessary for tempering, the temperature rises. There was a problem that the A part which is easy to warm exceeds the limit heating temperature (T2) which can maintain the specified hardness.

  Moreover, as shown in the graph of FIG. 7, when it is going to heat up both A part and B part in an appropriate temperature range (T1-T2), it will be longer than the heating time ((alpha)) in the case of FIG. 6, ((alpha) + (beta)). Had to heat.

  Therefore, in view of such circumstances, the present invention intends to provide a tempering method for a constant velocity universal joint outer ring that can be tempered to a uniform hardness in a short time.

  According to the first aspect of the present invention, there is provided a hardened hardened layer formed on the inner peripheral surface of the mouth portion of the constant velocity universal joint outer ring having a mouth portion in which an axial guide groove for guiding the torque transmitting member is formed on the inner peripheral surface. In the method of tempering a constant velocity universal joint outer ring tempered by induction heating, the mouse portion is pivoted in a ring-shaped coil formed by arranging a plurality of unit windings wound in a circumferential direction along a plane including an axis. Inserting in the direction, passing a current through the ring-shaped coil, generating an induction current in the axial direction in the mouse portion and induction heating for a predetermined time, and cooling the mouse portion that has been induction heated. It is a method to have.

  Since the unit winding of the ring-shaped coil is wound along a plane including the axis, an induced current in the axial direction can be generated in the mouse portion when a current is passed through the ring-shaped coil. If the induced current in the axial direction generated in the mouse portion is adjusted in the circumferential direction, the mouse portion can be heated with a difference in the circumferential direction. Specifically, if the induced current generated in the part corresponding to the guide groove of the mouse part is set to be smaller than the induced current generated in the other part of the mouse part, the bottom surface (inner surface of the guide groove close to the coil) ) Can be made closer to the temperature increase rate of the other inner surface far from the coil.

  According to a second aspect of the present invention, there is provided a hardened hardened layer formed on the inner peripheral surface of the mouth portion of the constant velocity universal joint outer ring having a mouth portion in which an axial guide groove for guiding the torque transmitting member is formed on the inner peripheral surface. In the method of tempering a constant velocity universal joint outer ring tempered by induction heating, the mouse unit is previously placed in a ring-shaped coil in which a plurality of unit windings wound along a plane including the axis are arranged in the circumferential direction. A magnetic flux shielding member made of a magnetic material is disposed so as to face the outer surface corresponding to the guide groove, and the mouse portion is inserted in the ring coil in the axial direction, and a current is supplied to the ring coil. And a step of generating an induced current in the axial direction in the mouse portion and induction heating for a predetermined time, and a step of cooling the induction heated mouse portion.

  In the part corresponding to the guide groove of the mouse part, the magnetic flux generated from the ring-shaped coil concentrates on the intervening magnetic flux shielding member, and thus is partially shielded. This suppresses heating of the hardened hardened layer on the bottom surface (inner surface) of the guide groove. That is, the temperature rising rate at the bottom surface of the guide groove near the coil can be made closer to the temperature rising rate at the other inner surface far from the coil.

  The invention according to claim 3 is a constant velocity integrally having a mouth portion in which an axial guide groove for guiding the torque transmitting member is formed on the inner peripheral surface and a stem portion in which a tooth mold portion such as serration is formed on the outer peripheral surface. In the tempering method of the constant velocity universal joint outer ring, the hardened hardened layer formed on each of the inner peripheral surface of the mouse portion and the outer peripheral surface of the stem portion of the universal joint outer ring is tempered by induction heating. In the cylindrical coil, the stem portion is inserted in the axial direction, and a plurality of unit windings wound along a plane including the axis are arranged in the circumferential direction in the ring-shaped coil. A magnetic flux shielding member made of a magnetic material is disposed so as to face the outer surface corresponding to the guide groove, and the mouse portion is inserted into the ring coil in the axial direction; and the cylindrical coil and the ring shape A current is passed through the coil, Generating an induced current in the circumferential direction in the system portion and generating an induced current in the axial direction in the mouse portion to induce and heat the stem portion and the mouse portion for a predetermined time; and the induction-heated stem portion and mouse Cooling the part.

  In the part corresponding to the guide groove of the mouse part, the magnetic flux generated from the ring-shaped coil concentrates on the intervening magnetic flux shielding member, and thus is partially shielded. This suppresses heating of the hardened hardened layer on the bottom surface (inner surface) of the guide groove. That is, the temperature rising rate at the bottom surface of the guide groove near the coil can be made closer to the temperature rising rate at the other inner surface far from the coil. Moreover, since the hardening hardening layer formed in the outer peripheral surface of a stem part is equidistant from a cylindrical coil over the perimeter, it is heated uniformly.

  According to a fourth aspect of the present invention, in the method for tempering a constant velocity universal joint outer ring according to any one of the first to third aspects, a plurality of unit windings of the ring-shaped coil are continuously connected to a winding conductor. It is produced by winding a plurality of times.

  The structure of the ring coil can be simplified. In addition, peripheral devices such as an oscillation device and a matching device connected to the ring coil can be reduced. This can reduce the manufacturing cost of the induction heating device used in the present invention.

  A fifth aspect of the present invention is the method of tempering a constant velocity universal joint outer ring according to the third aspect, wherein a plurality of unit windings of the ring-shaped coil are produced by continuously winding a winding conductor. The cylindrical coil and the ring coil are connected in series or in parallel.

  Peripheral devices such as an oscillating device and a matching device used for the cylindrical coil and the ring coil can be shared, and the manufacturing cost can be reduced.

  The invention according to claim 6 is a constant velocity integrally having a mouth portion in which an axial guide groove for guiding the torque transmitting member is formed on the inner peripheral surface and a stem portion in which a tooth mold portion such as serration is formed on the outer peripheral surface. In an induction heating device that induction-heats a hardened hardened layer formed on each of the inner peripheral surface of the mouth portion and the outer peripheral surface of the stem portion of a universal joint outer ring, the induction joint is disposed around the stem portion and wound in the circumferential direction. A cylindrical coil, a ring coil that is disposed around the mouse portion and is wound around a plane including an axis, and a plurality of unit windings are arranged in the circumferential direction, and the mouse portion and the ring coil And a magnetic flux shielding member made of a magnetic material disposed opposite to the outer surface corresponding to the guide groove of the mouse portion.

  According to the induction heating device of the present invention, the magnetic flux generated from the ring-shaped coil concentrates on the intervening magnetic flux shielding member at a portion corresponding to the guide groove of the mouse portion, and thus is partially shielded. This suppresses heating of the hardened hardened layer on the bottom surface (inner surface) of the guide groove. That is, the temperature rising rate at the bottom surface of the guide groove near the coil can be made closer to the temperature rising rate at the other inner surface far from the coil. Moreover, since the hardening hardening layer formed in the outer peripheral surface of a stem part is equidistant from a cylindrical coil over the perimeter, it is heated uniformly.

  According to the tempering method of the constant velocity universal joint outer ring of the present invention, the heating rate of the bottom surface of the guide groove near the coil of the mouse portion can be made close to the heating rate of the other inner surface far from the coil. In other words, the heating temperature difference between the concave portion and the convex portion on the inner peripheral surface of the mouse portion during a predetermined heating time can be reduced, and the entire inner peripheral surface of the mouse portion can be formed to have a uniform and appropriate hardness. Therefore, compared with the case where tempering is performed by a conventional method, the mechanical strength of the bottom of the guide groove, particularly the bottom of the guide groove, can be increased, and a high-quality constant velocity universal joint outer ring having a long product life can be manufactured. . In addition, the heating can be performed in a shorter time than before, and the cycle time can be shortened.

  The present invention is a method of tempering the outer ring in a constant velocity universal joint having a structure in which a torque transmission member is interposed between an inner ring and an outer ring in a constant velocity universal joint for an automobile, for example. FIG. 1 shows an embodiment of the present invention, and more specifically, is a schematic side view showing a state in which an outer ring is set in an induction heating apparatus used in the present invention. FIG. 2 is a sectional view taken along line XX in FIG. Hereinafter, the present invention will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the outer ring 1 is formed by integrally forming a cup-shaped mouth portion 2 and a stem portion 3 protruding from a closed end of the mouth portion 2 with a steel material. On the outer peripheral surface of the stem part 3, tooth type parts such as serrations and splines for fitting with other power transmission shafts are formed (not shown). A plurality (three in FIG. 2) of guide grooves 4 in the axial direction in which the torque transmitting member is guided are formed on the inner peripheral surface of the mouse portion 2 at equal intervals in the circumferential direction. That is, the stem portion 3 has a uniform shape in the circumferential direction, while the mouse portion 2 includes a thin-walled portion 2a in which the bottom surface 4a of the guide groove 4 is formed, and other thick-walled portions. 2b are alternately provided in the circumferential direction.

  Further, a hardened layer by quenching is formed in advance on the outer peripheral surface of the stem portion 3 and the inner peripheral surface of the mouse portion 2, and the hatched portion in FIG. 2 is a quenching formed on the inner peripheral surface of the mouse portion 2. It is a hardened layer.

  The induction heating device used in the tempering method according to the present invention will be described. The induction heating device includes a ring coil 5, a cylindrical coil 6, upper and lower jigs 7 and 8, and a magnetic flux shielding member 9. .

  The ring-shaped coil 5 is formed by arranging a plurality of unit windings 10 wound around a plane including an axis in the circumferential direction. In this case, the plurality of unit windings 10 are arranged. Is a winding conductor wound continuously several times. The unit winding 10 is wound in a rectangular shape, and has a linear portion 10a parallel to the axis on the inner diameter side. Further, as shown in FIG. 2, the unit windings 10 are arranged at equal distances from the axis in the radial direction and at equal intervals in the circumferential direction, that is, are arranged radially around the axis.

  As shown in FIG. 2, on the inner diameter side of the ring-shaped coil 5, three plate-shaped magnetic flux shielding members 9 made of a magnetic material are arranged at equal intervals in the circumferential direction. The magnetic flux shielding member 9 is formed in a circular arc shape along the circumferential direction of the ring-shaped coil 5, and is disposed in the vicinity of the rectangular parallelepiped of the ring-shaped coil 5 or the straight portion 10 a. When viewed from the side, the magnetic flux shielding member 9 is arranged in parallel to the axis as shown in FIG.

  The cylindrical coil 6 is manufactured by winding a plurality of winding conductors in the circumferential direction. The cylindrical coil 6 is disposed on a coaxial line above the ring-shaped coil 5, and the cylindrical coil 6 and the ring-shaped coil 5 are connected in series or in parallel. That is, the ring-shaped coil 5 and the cylindrical coil 6 can share an oscillating device and a matching device (not shown), and the oscillating device and the matching device necessary for this induction heating device may be provided one by one.

  The process of the tempering method of this invention is demonstrated. First, the upper jig 7 and the lower jig 8 are attached to the upper and lower ends of the outer ring 1, that is, the end of the stem 3 and the end of the mouse 2. Then, while the outer ring 1 is supported by the upper and lower jigs 7 and 8, as shown in FIG. 1, the outer ring 1 is inserted into the cylindrical coil 6 and the ring coil 5, and the mouse part 2 of the outer ring 1 is arranged in the ring coil 5. Then, the stem portion 3 is disposed in the cylindrical coil 6. Further, as shown in FIG. 2, the outer surface corresponding to the guide groove 4 of the mouse portion 2, that is, the outer surface of the thin portion 2 a is disposed so as to face the magnetic flux shielding member 9. Further, in the illustrated example, the circumferential width dimension of the magnetic flux shielding member 9 is formed to be substantially the same as the circumferential width dimension of the thin portion 2 a of the mouse portion 2.

  In this state, a high-frequency current is passed through the cylindrical coil 6 and the ring-shaped coil 5 to inductively heat the outer ring 1 for a predetermined time. Since the hardening hardening layer formed in the outer peripheral surface of the stem part 3 is equidistant from the cylindrical coil 6 over the perimeter, it is uniformly induction-heated.

  At the same time, when a current flows through the ring-shaped coil 5 (the straight portion 2a parallel to the axial direction), an induced current is generated in the axial direction in the mouse portion 2 by the magnetic flux generated from the ring-shaped coil 5, and induction heating starts.

  At this time, the magnetic flux from the ring-shaped coil 5 to the thin portion 2a of the mouse portion 2 concentrates on the intervening magnetic flux shielding member 9, and is partially shielded. This suppresses heating in the hardened hardened layer on the inner surface of the thin portion 2a, for example, the A 'portion. That is, when comparing the A ′ portion of the thin wall portion 2a with the C portion of the thick wall portion 2b having the same distance L as the A ′ portion from the link coil 5, the A ′ portion where the magnetic flux shielding member 9 is interposed is compared. However, the progress of heating is suppressed as compared with the C portion in which the magnetic flux shielding member 9 is not interposed.

  Therefore, as shown in the graph of FIG. 3, when the induction heating according to the method of the present invention is performed with the same heating time α (see FIG. 6) as the conventional method, the heating temperature of the A ′ portion according to the present invention is the magnetic flux shielding. It becomes lower than the heating temperature of part A (indicated by a two-dot chain line) by a conventional method having no member. And according to this invention, it became possible to heat up both A 'part of the thin part 2a in FIG. 2, and B part of the thick part 2b inner surface in an appropriate temperature range (T1-T2). 2 and the part A in FIG. 5 are the same part.

  Thus, after each of the outer peripheral surface of the stem portion 3 and the inner peripheral surface of the mouse portion 2 is appropriately and uniformly heated, the outer ring 1 is transported to a cooling device and cooled by jetting water to the outer ring 1. The tempering process is completed.

  The present invention is not limited to the above-described embodiment, and may be a case where the magnetic flux shielding member 9 is not interposed between the thin portion 2a of the mouse portion 2 and the ring-shaped coil 5 (not shown). That is, it is only necessary that the induced current in the axial direction of the mouse portion 2 generated by the ring-shaped coil 5 can be reduced in the thin portion 2a and increased in the thick portion 2b. For example, the unit windings 10 are arranged more densely than the thin part 2a at the position of the thin part 2a, or the unit windings 10 are arranged at the position of the thin part 2a from the position of the thick part 2b. The same effect can be achieved by disposing them away. Further, the unit windings 10 may be independent from each other, and the amount of current flowing through the unit windings 10 may be made to flow less at the position of the thin portion 2a than at the position of the thick portion 2b.

  Of course, the number of turns of the ring-shaped coil and the cylindrical coil can be variously changed in a range not departing from the gist of the present invention, depending on the shape of the outer ring to be tempered.

It is a schematic side view which shows one Example of the tempering method of the constant velocity universal joint outer ring | wheel which concerns on this invention. It is XX sectional drawing of the said FIG. It is the graph which showed each temperature rise of the thin part inner surface of a mouse | mouth part at the time of tempering an outer ring | wheel by this invention, and a thick part inner surface. It is a schematic side view which shows the Example of the tempering processing method of the conventional constant velocity universal joint outer ring | wheel. FIG. 5 is a transverse sectional view of FIG. 4. It is the graph which showed each temperature rise of the thin part inner surface of a mouse | mouth part at the time of tempering the outer ring | wheel by the conventional method, and the thick part inner surface. It is the graph which showed each temperature rise in the thin part inner surface of a mouse | mouth part at the time of tempering the outer ring | wheel on another conditions by the conventional method, and the thick part inner surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer ring 2 Mouse part 3 Stem part 4 Guide groove 5 Ring coil 6 Cylindrical coil 9 Magnetic flux shielding member 10 Unit winding

Claims (6)

A quench hardening layer formed on the inner peripheral surface of the mouse portion of the constant velocity universal joint outer ring having a mouth portion formed with an axial guide groove for guiding the torque transmission member on the inner peripheral surface is tempered by induction heating, etc. In the tempering method for the outer ring of the speed universal joint,
Inserting the mouse portion in the axial direction into a ring-shaped coil formed by arranging a plurality of unit windings wound along a plane including the axis in the circumferential direction;
Passing an electric current through the ring-shaped coil, generating an induction current in the axial direction in the mouse part, and induction heating for a predetermined time; and
Cooling the mouse part that has been induction heated;
A method of tempering a constant velocity universal joint outer ring, comprising: A quench hardening layer formed on the inner peripheral surface of the mouse portion of the constant velocity universal joint outer ring having a mouth portion formed with an axial guide groove for guiding the torque transmission member on the inner peripheral surface is tempered by induction heating, etc. In the tempering method for the outer ring of the speed universal joint,
Magnetic flux made of a magnetic material so as to face the outer surface corresponding to the guide groove of the mouse portion in advance in a ring-shaped coil formed by arranging a plurality of unit windings wound along a plane including the axis in the circumferential direction. A step of arranging a shielding member and inserting the mouse portion in the ring coil in the axial direction;
Passing an electric current through the ring-shaped coil, generating an induction current in the axial direction in the mouse part, and induction heating for a predetermined time; and
Cooling the mouse part that has been induction heated;
A method of tempering a constant velocity universal joint outer ring, comprising: The mouse portion of the constant velocity universal joint outer ring integrally having a mouth portion in which an axial guide groove for guiding a torque transmission member is formed on the inner peripheral surface and a stem portion in which a tooth mold portion such as serration is formed on the outer peripheral surface. In the tempering method of the constant velocity universal joint outer ring, induction hardening and tempering of the hardened hardened layer formed on each of the inner peripheral surface and the outer peripheral surface of the stem part,
In a ring coil formed by inserting the stem portion in the axial direction into a cylindrical coil wound in the circumferential direction and arranging a plurality of unit windings wound in the circumferential direction along the plane including the axis Preliminarily arranging a magnetic flux shielding member made of a magnetic material so as to face the outer surface corresponding to the guide groove of the mouse part, and inserting the mouse part in the ring-shaped coil in the axial direction;
An electric current is passed through the cylindrical coil and the ring coil, an induced current is generated in the circumferential direction in the stem portion, an induced current is generated in the axial direction in the mouse portion, and the stem portion and the mouse portion are kept at a predetermined time. Induction heating,
Cooling the stem portion and the mouse portion that have been induction-heated;
A method of tempering a constant velocity universal joint outer ring, comprising:   The tempering of the constant velocity universal joint outer ring according to any one of claims 1 to 3, wherein the plurality of unit windings of the ring-shaped coil are produced by continuously winding a winding conductor. Processing method.   4. A plurality of unit windings of the ring-shaped coil are produced by continuously winding a winding conductor, and the cylindrical coil and the ring-shaped coil are connected in series or in parallel. The method for tempering the constant velocity universal joint outer ring according to claim 1. The mouse portion of the constant velocity universal joint outer ring integrally having a mouth portion in which an axial guide groove for guiding a torque transmission member is formed on the inner peripheral surface and a stem portion in which a tooth mold portion such as serration is formed on the outer peripheral surface. In the induction heating apparatus for induction heating the quench hardening layer formed on each of the inner peripheral surface and the outer peripheral surface of the stem portion,
A plurality of cylindrical coils arranged around the stem portion and wound in the circumferential direction, and a plurality of unit windings arranged around the mouse portion and wound along a plane including the axis are arranged in the circumferential direction. And a magnetic flux shielding member made of a magnetic material disposed between the mouse portion and the ring-shaped coil and facing the outer surface corresponding to the guide groove of the mouse portion. An induction heating device characterized by.

Images