JP5619952B2 - Manufacturing method of constant velocity joint outer ring - Google Patents

Description

  The present invention relates to a method for manufacturing a constant velocity joint outer ring.

  An outer ring such as a fixed constant velocity joint for automobiles includes a fitting portion between a cup portion and a mating hub such as a shaft portion, and a plurality of rolling track grooves are provided on an inner diameter surface of the cup portion. In addition, there is a shaft portion having a portion in which a tooth mold portion such as serration is formed. In order to ensure the fatigue strength of the track grooves on the inner surface of the tooth mold part and the cup part, a hardened layer is formed by induction hardening on the outer peripheral surface of the stem part including the tooth mold part and the inner surface of the cup part. (For example, refer to Patent Document 1). As an induction hardening apparatus, an induction hardening coil, a cooling means, and an upper center pin and a lower center pin that support an outer ring are known as main components.

  The basic operation of the quenching apparatus will be described. First, the outer ring is supported in the vertical direction by the upper and lower center pins and brought close to the induction heating coil. Next, while rotating the outer ring, the induction heating coil is energized to heat the surface portion of the corresponding outer ring to the quenching temperature. Cooling liquid is sprayed onto the heated portion by a cooling means, rapidly cooled and quenched. Usually, the product is treated by one quenching, but there is also a method in which the quenching operation is sequentially repeated while raising the outer ring to the induction heating coil. As another method, there is a quenching method in which the induction heating coil is lowered with respect to the outer ring.

  In addition, quality inspection is performed to measure the surface hardness of the outer ring and the depth of the effective hardened layer after quenching. The effective hardened layer depth is measured by cutting the outer ring and measuring the cross section with a hardness meter. Therefore, the cut outer ring cannot be used. Further, although there is an eddy current type non-destructive inspection method for measuring the effective hardened layer, only a part of the hardened layer of the outer ring can be measured by one measurement. Therefore, when there are many inspection object portions, a great amount of man-hours are required for the measurement work. Such a sampling inspection was performed for the quality inspection of the quenched outer ring.

Japanese Patent Laid-Open No. 9-96317

  However, if it is determined in the sampling inspection that the processing state of the outer ring, such as the depth of the hardened hardened layer, does not meet the predetermined quality standard, whether or not the quality standard is satisfied for other products not subjected to the sampling inspection It was difficult to judge. And because products that do not meet the quality standards may be mixed in the product, all the product groups (products in the same lot) that are considered to have been manufactured under the same conditions as those that do not meet the quality standards were discarded. . Furthermore, since the difference in processing conditions between those that satisfy the quality standard and those that do not satisfy the quality standard is unknown, it is difficult to identify the cause that does not satisfy the quality standard.

  In view of the above-described circumstances, the present invention intends to provide an outer ring manufacturing method capable of individually managing the processing conditions of the outer ring.

  The invention of claim 1 includes a step of induction-hardening the constant velocity joint outer ring, measuring a quenching condition for each outer ring to be hardened, an identification code for specifying the outer ring one by one, and each A step of associating and storing the measured quenching processing conditions of the outer ring, a step of attaching the identification code to the corresponding outer ring before or after the quenching, and a sampling inspection after the quenching The identification code given to the outer ring determined not to meet the predetermined quality standard is compared with the stored identification code to obtain the quenching processing condition of the outer ring, and the quenching process Is there any other outer ring identification code for the quenching process condition that matches the quenching process condition for the outer ring that does not satisfy the quality criteria by comparing the conditions with the stored quenching process condition for each outer ring? Constant-velocity joint outer ring having a process of checking whether or not It is a manufacturing method.

  According to the method of the first aspect, the outer ring can be individually managed by attaching the identification code, and the processing condition of each outer ring and the identification code can be managed in association with each other. Therefore, the machining condition of the outer ring can be known immediately from the identification code. In general, outer rings having the same processing conditions tend to be in the same processing state. In other words, according to the present invention, it is possible to easily find an outer ring having the same processing conditions as a specific processing condition. Therefore, if there is an outer ring that does not satisfy a predetermined quality standard in the sampling inspection of the outer ring, You can easily find the outer ring. As a result, it is possible to reduce the labor of quality inspection and improve the reliability of the quality of the outer ring.

  According to the method of manufacturing the constant velocity joint outer ring of the present invention, the outer ring can be individually managed by attaching an identification code, and the processing conditions of each outer ring and the identification code can be managed in association with each other. Therefore, the machining condition of the outer ring can be known immediately from the identification code. Moreover, the outer ring | wheel of the same process conditions as a specific process condition can be discriminate | determined easily. Furthermore, since the identification code and the quenching process condition are stored in all the outer rings, it is possible to grasp the difference in the quenching process condition between the outer ring that satisfies the predetermined quality standard and the outer ring that does not satisfy the predetermined quality standard. it can. This makes it possible to investigate the cause of not satisfying the quality standard. Thus, according to the present invention, the reliability of the quality of the outer ring is improved.

It is a schematic block diagram which shows one Embodiment of the quenching quality control apparatus of the constant velocity joint outer ring | wheel which concerns on this invention. It is a simplification figure showing the principal part of a hardening device. It is a simplification figure showing the principal part of an inspection device. It is a flowchart figure which shows one Embodiment of the quenching quality control method of the constant velocity joint outer ring | wheel which concerns on this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of a quench quality control apparatus for a constant velocity joint outer ring according to the present invention. As shown in FIG. 1, the apparatus of the present invention includes a quenching device 1, an electronic control unit 2, a marking device 3, a measuring unit 14, and an inspection device 4 as main components.

  The said quenching apparatus 1 is an apparatus which performs induction hardening processing on the surface of the outer ring | wheel of the constant velocity joint for motor vehicles, for example. As shown in FIG. 2, the outer ring 5 includes a mouth portion 15 that is open at one end in the axial direction, and a stem portion 16 that protrudes integrally from the other closed end of the mouth portion 15. The stem portion 16 is engraved with a tooth mold portion that is inserted and fitted into the hollow portion of the external transmission shaft member. The quenching apparatus 1 includes an induction heating coil 6 for high-frequency induction heating of the surface of the outer ring 5, and a pair of upper center pin 7 and lower center pin 8 that support the outer ring 5. In addition, a cooling means (not shown) is also provided for rapid cooling by injecting cooling water to the outer ring 5 after induction heating. The upper center pin 7 and the lower center pin 8 are respectively disposed on a movable base (not shown) that can move up and down, and the distance between the center pins 7 and 8 is adjustable. As another method, the induction heating coil 6 may have a mechanism that can move up and down with respect to the outer ring 5. Further, the upper center pin 7 and the lower center pin 8 are configured to be rotationally driven by a motor (not shown). The induction heating coil 6 is supplied with electric power from a high frequency power source (not shown).

  As shown in FIG. 1, the electronic control unit 2 has a storage unit 9, which stores an identification code for identifying a large number of outer rings one by one, and quenching conditions for each outer ring. It is associated and stored. Here, the identification code includes letters, numbers, symbols, figures, and the like. The quenching conditions include the amount and frequency of power supplied from the high-frequency power source to the induction heating coil, the position and rotation speed of the outer ring being heated, the flow rate (injection amount) of cooling water, the water temperature, etc. It is defined to include conditions that can affect the quenching quality of the outer ring.

  This apparatus is provided with a measuring unit 14 (measuring means) including various sensors and measuring devices for obtaining these quenching processing conditions for each outer ring, and quenching is performed from the measuring unit 14 to the storage unit 9. Condition data is configured to be transmitted.

  The electronic control unit 2 includes an input unit 10, a search unit 11, and a display unit 12 (output unit). The input unit 10 is a part for inputting a specific identification code or a specific quenching process condition of the outer ring, and the search unit 11 is an input unit among the identification code and the quenching process condition stored in the storage unit 9. 10 is a means (search means) for searching for the other one related to the specific one input to 10. The display unit 12 is a means for displaying the identification code or the quenching process condition found by the search unit 11.

  The marking device 3 is, for example, a laser marker, a marking machine, or the like, and is controlled by the electronic control unit 2 so as to attach the identification code stored in the storage unit 9 to the corresponding outer ring.

  The inspection device 4 measures the depth of the hardened and hardened layer of the outer ring that has been hardened. For example, a nondestructive hardened layer inspection machine such as an eddy current hardened layer inspection device is preferable. As shown in FIG. 3, the inspection device 4 has a measurement probe 13, and brings the probe 13 close to the inspection target portion of the hardened and hardened layer of the outer ring indicated by the hatched portion in the figure, and the AC generated by the probe 13. The outer ring is magnetized by a magnetic field. And the depth of a hardened layer is measured by detecting the magnetization delay characteristic which changes with the depth of the hardened layer of an outer ring | wheel. In addition to this inspection method, the outer ring may be cut and the cut surface may be measured with various hardness meters. Further, other quality inspections may be performed.

Hereinafter, the quenching quality control method of the constant velocity joint outer ring using the apparatus of the present invention will be described with reference to the flowchart of FIG.
First, an outer ring quenching process is performed. Specifically, as shown in FIG. 2, the outer ring 5 is supported in the vertical direction by the upper center pin 7 and the lower center pin 8, and the outer ring 5 is inserted into the center of the induction heating coil 6. Next, both the center pins 7 and 8 are rotated, and along with this, the induction heating coil 6 is energized while rotating around the outer ring 5 and the axis, thereby heating the surface portion of the corresponding outer ring 5 to the quenching temperature. Cooling water is sprayed onto the heated portion of the outer ring 5 by a cooling means (not shown) and quenched to quench. Usually, the product is processed by one quenching, but there is also a method of quenching a predetermined portion of the outer ring 5 while lowering the outer ring 5 with respect to the induction heating coil 6. As another method, the induction heating coil 6 may move up and down with respect to the outer ring 5. This quenching operation is repeated in many outer rings 5.

  Further, during the quenching process, the quenching process condition of each outer ring is measured by the measuring unit 14 provided in the quenching apparatus, and the data of the quenching process condition is transmitted to the storage unit 9 of the electronic control unit 2. Is done. And in the memory | storage part 9, hardening processing conditions and an identification code are linked | related and memorize | stored for every outer ring | wheel.

  The quenched outer ring is conveyed to the marking device 3 by a conveying means (not shown), and the marking device 3 attaches an identification code to the corresponding outer ring according to an instruction from the electronic control unit 2. Thus, by assigning an identification code to the outer ring, the outer ring can be managed individually, and the processing conditions of each outer ring can be managed in association with the identification code.

Hereinafter, a case where a predetermined or arbitrary outer ring is extracted from a large number of outer rings after marking and the quality of the outer ring is inspected will be described.
In the quality inspection, it is determined whether the processed state of the extracted outer ring satisfies a predetermined quality standard. Specifically, for example, it is determined whether or not the depth of the hardened hardening layer of the outer ring has reached a predetermined reference depth. When it is determined that there is (one or more) outer rings that have undergone sampling inspection that have not reached the depth of the predetermined hardened layer, the following steps are performed.

  First, the identification code attached to the outer ring that does not satisfy the quality standard is confirmed, and the identification code is input to the input unit 10 of the electronic control unit 2. Then, the search unit 11 collates the identification code stored in the storage unit 9 with the identification code input to the input unit 10 (for the outer ring that does not satisfy the quality standard), and the outer ring that does not satisfy the quality standard. Find the quenching process conditions. The found processing conditions are displayed on the display unit 12.

  Next, the quenching conditions for the outer ring that does not satisfy the quality standard are input to the input unit 10. Then, the search unit 11 collates the machining conditions stored in the storage unit 9 with the inputted machining conditions (for the outer ring that does not satisfy the quality standard). If there is another outer ring of the quenching process condition that matches the input quenching process condition, the identification code is displayed on the display unit 12. At this time, when there are a plurality of outer rings having the same processing conditions, all of the identification codes are displayed. If there is no match, that effect is displayed on the display unit 12.

  Generally, an outer ring manufactured under the same quenching processing conditions tends to be in the same processing state. Therefore, when an outer ring identification code that matches the processing conditions of the outer ring that does not satisfy the quality standard is found, it is determined that the outer ring with the found identification code does not satisfy the quality standard.

  Note that the above “match with machining conditions” means that the machining conditions input to the input unit 10, in other words, the sample machining conditions completely match the other stored machining conditions, and the sample machining conditions It is defined that the stored machining conditions are included in the predetermined allowable range. That is, if the sample processing conditions consist of six items of the electric energy / frequency of the induction heating coil, the position / rotation speed of the outer ring, the flow rate / water temperature of the cooling water, for example, search for the outer ring with the processing conditions that match the five items. Alternatively, the outer ring of the machining condition that falls within 10% of the numerical value of each item may be searched. The sample processing conditions are not limited to the processing conditions of the outer ring that does not meet the quality standard by sampling inspection, but are the processing conditions of the outer ring that satisfy (or do not satisfy) the predetermined quality standard obtained from the past processing condition data. There may be.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention. For example, the marking process for attaching an identification code corresponding to the outer ring may be performed in advance before quenching. Further, the structure of the quenching apparatus is not limited to that of the above embodiment, and it is possible to apply general outer ring parts for automobiles such as a fixed outer ring or a sliding outer ring.

DESCRIPTION OF SYMBOLS 1 Hardening apparatus 2 Electronic control part 3 Marking apparatus 4 Inspection apparatus 5 Outer ring 9 Storage part 10 Input part 11 Search part 12 Display part 14 Measurement part

Claims (1)

Inductively processing the constant velocity joint outer ring, and measuring the quenching processing conditions for each outer ring to be hardened,
Storing the identification code for specifying the outer rings one by one and the measured quenching processing conditions of each outer ring in association with each other;
The step of attaching the identification code to the corresponding outer ring before or after the quenching process;
By comparing the identification code given to the outer ring that is determined not to satisfy the predetermined quality standard in the sampling inspection after the quenching process, with the stored identification code, the quenching process condition of the outer ring is determined. The other quenching process conditions that match the quenching process conditions of the outer ring that does not satisfy the quality standards are verified by comparing the quenching process conditions with the stored quenching process conditions for each outer ring. A method for manufacturing a constant velocity joint outer ring, comprising a step of inspecting whether or not there is an outer ring identification code.

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