JP3137963U - Steel ball inspection equipment - Google Patents

Abstract

The present invention includes a conventional inspection device for inspecting scratches of steel balls and an inspection device for discriminating between different materials and determining the quenching state. Simplification, saving of installation area and shortening of processing time.
An eddy current flaw detection apparatus having a first probe that performs an external flaw inspection of an overcoil system in which a high-frequency current flows, and a different material discrimination and quenching state determination in an overcoil system through which a low-frequency current is passed. The eddy current flaw detection apparatus having the second probe 8 for performing the inspection is built in one appearance inspection apparatus, the first and second probes are installed in the vicinity of the steel balls, and the appearance defect inspection is performed in one appearance inspection apparatus. In addition, it is now possible to check different materials and quenching conditions almost simultaneously.
[Selection] Figure 1

Description

  The present invention enables steel balls used in ball bearings, ball screws, linear guides, constant velocity joints, etc. to be inspected almost simultaneously in a single inspection device for inspection of external flaws, discrimination of different materials, and quenching status. The present invention relates to a ball inspection apparatus.

  Steel balls are inspected by an inspection device after production to determine the presence or absence of surface defects and to distinguish between non-defective products and defective products. Currently, steel ball inspection devices currently used are optical or 2 of an apparatus for inspecting a surface defect of a steel ball using an image processing method and an eddy current flaw detection apparatus for detecting a fine crack-like scratch that is difficult to detect by the optical inspection (for example, see Patent Document 1). As disclosed in Patent Document 1, the eddy current flaw detector is composed of a steel ball rotating device, an inspection cycle control device, and an eddy current flaw detector, and the detection sensor is rotated by a positioning jig. It is configured to be fixed to the apparatus and connected to an eddy current flaw detector through a connector.

  In order to inspect using this eddy current flaw detector, the reference defect sphere is first adjusted in the rotation device, the signal obtained from this defect is adjusted, the detection sensitivity is set, and then the steel ball to be inspected is placed on the rotation device. The inspection cycle control system scans the sensor over the entire surface, detects defects on the surface of the steel ball, and compares it with the preset defect signal of the reference defect ball to determine whether the product is good or defective. It is taken.

On the other hand, in order to inspect the foreign material discrimination and the quenching state judgment for the steel ball, a device completely different from the device for detecting the surface defect is used (for example, refer to Patent Document 2), or a coil in which a test piece is inserted or Measure the coil hardened layer depth by passing an alternating current with a frequency of 1 KHz or less to the coil placed near the test piece and measure the coil inductance value, measure the unhardened steel material, or discriminate between different materials The method of doing is taken.
JP 2000-310619 A JP 2007-40865 A

  However, the apparatus used for each of the above inspections is a completely different apparatus that performs the inspection of the appearance defect of the steel ball, the distinction of the steel material, and the inspection of the quenching state, respectively. Since it is an arrangement, it is necessary to install an inspection device for each process, which increases the installation area, increases the cost of equipment, and requires a long time due to a long process.

  Therefore, the present invention addresses the actual situation as described above, and particularly finds that two probes that pass currents having different frequencies are installed in the vicinity of the steel ball in one visual inspection apparatus. It is intended to achieve the simplification of the entire inspection apparatus, the saving of the installation area, and the shortening of the processing time by inspecting the appearance defect of the steel ball, the discrimination of different materials and the quenching state almost simultaneously.

  In other words, the steel ball inspection device of the present invention that achieves the above-described object includes an eddy current flaw detection device that performs an external flaw inspection having a first probe of an upper coil system that supplies a high-frequency current, and a low-frequency current. An eddy current flaw detection device that performs different material discrimination and quenching status determination with a second probe of the top coil system is built in one appearance inspection device, and the first and second probes are installed in the vicinity of the steel ball, It is characterized in that it is possible to inspect the appearance flaw inspection, the discrimination of different materials and the determination of the quenching state almost simultaneously in one appearance inspection apparatus.

  According to a second aspect of the present invention, a penetrating coil type probe is used as the second probe, and the eddy current flaw detection device having the above-described first coil type probe that conducts the high frequency current for inspecting the appearance scratch, and the low frequency current An eddy current flaw detection device that performs different material determination and quenching state determination with a second probe of a penetrating coil method is built in one appearance inspection device, and the first and second probes are installed in the vicinity of the steel ball, It is characterized in that it is possible to inspect the appearance flaw inspection, the discrimination of different materials and the determination of the quenching state almost simultaneously in one appearance inspection apparatus. In each of the above cases, an alternating current of 0.65 MHz to 3 MHz is generally used for the high frequency and 50 Hz to 1500 KHz is used for the low frequency.

  Here, the eddy current flaw detection apparatus for inspecting the appearance of the steel ball passes a high-frequency alternating current through an excitation coil around a detection coil built in a probe installed in the vicinity of the steel ball, so that the surface of the steel ball is Utilizes the electromagnetic induction phenomenon in which eddy current is induced. When there is no flaw, the eddy current flows concentrically on the surface of the steel ball, but when there is a flaw, the eddy current does not flow concentrically and the place of the flaw is disturbed. A change in the distribution of eddy current is detected by a detection coil to detect a flaw. In this case, when a high frequency is used, the eddy current density on the surface of the steel ball increases, and it becomes easy to detect minute scratches.

  On the other hand, the electrical conductivity and magnetic permeability specific to the material are used for the inspection of the different material discrimination and the quenching state judgment. When a low-frequency alternating current is passed through an exciting coil arranged around a steel ball, the eddy current generated in the material is affected by the magnetic permeability inherent in the material, and the voltage and phase change. This change in voltage and phase is detected, and different materials are discriminated and quenched. When the low frequency is used, eddy current enters the material deeper than the high frequency, so that the change in magnetic permeability and phase becomes clear, and different material discrimination and quenching state discrimination are facilitated.

  In the present invention, as described above, an upper coil type probe that passes a high-frequency current to detect scratches is used as a first probe, and an upper coil that passes a low-frequency current to perform different material discrimination and quenching status judgment. The probe of the system is set as the second probe, and each of them is installed in the vicinity of the steel ball, or the first probe for detecting the flaw is left in the upper coil system, while different material discrimination and quenching state judgment are performed. As for the second probe, by using a penetrating coil type probe and installing them in one inspection device, it is possible to perform two steps in one step, and the inspection device is simple. And saving installation space and shortening the processing time.

  As described above, the present invention is configured by incorporating each detection sensor (probe) for performing appearance flaw inspection, foreign material discrimination and quenching state judgment, and an eddy current flaw detector connected thereto in one visual inspection device. In addition, while rotating the steel ball and performing appearance scratch inspection on the entire surface, it is also possible to perform foreign material discrimination and quenching status judgment at the same time, so inspection of external scratches, foreign material discrimination and quenching status judgment should be performed almost simultaneously. Conventionally, in the case of a steel ball having a diameter of 8.731 mm, about 5 hours are required to inspect the appearance of 32,000 balls, and about 10 hours are required for different material discrimination and quenching status judgment. , It took about 15 minutes from taking out the ball to throwing it in at the same time. By inspecting, the time required from taking out the ball to throwing in can be saved, and the processing time for the appearance scratch inspection, the foreign material discrimination, and the quenching state judgment requires 15 hours in two steps. However, it can be reduced to 10 hours by simultaneously inspecting in one inspection apparatus. Therefore, since it took 15 hours and 15 minutes to complete all the two steps in the past, it can be shortened to 10 hours by simultaneously inspecting, so the inspection processing time can be shortened by 34%, Moreover, it has a great effect on simplification of the inspection apparatus and saving of the installation area.

  Specific embodiments of the present invention will be described below with reference to the accompanying drawings. 1 and 2 show an outline of an eddy current flaw detection apparatus which is a main part of the present invention incorporated in the inspection apparatus of the present invention, and FIG. 1 shows a distinction between a first probe of an upper coil system for detecting scratches and different materials. , The top coil type second probe for determining the quenching state is installed in the vicinity of each steel ball, FIG. 2 is a different material discrimination from the top coil type first probe for performing external flaw inspection, A penetrating coil type second probe that performs quenching state determination is installed in one inspection apparatus.

  In FIG. 1, 1 is a steel ball to be inspected, 2 is a drive roller, 3 is a support roller, 4 is a control roller, 5 is a holder, 6 is an eccentric gear, 7 is a flaw detection probe, 8 is a foreign material discrimination, and a quenching state. The steel ball is fixed at a predetermined position by a drive roller 2, a support roller 3, and two control rollers 4, which are determination probes. An eccentric gear 6 is attached to the other ends of the two control rollers 4. By rotating the drive roller 2, the steel ball 1 on the drive roller 2 rotates, and at the same time, the control roller 4 also rotates. At this time, the steel ball 1 is twisted by the eccentric gear 6 whose center axis is eccentric and rotates. The steel ball 1 rotating with a twist is rotated so as to draw the meridian locus shown in FIG. 3 with respect to the tips of the two detection probes 7 and 8, and the first probe 7 rotates the entire ball 1. At the same time, the surface is inspected for scratches, and at the same time, the second probe 8 discriminates the different material and determines the quenching state. The meridian interval S is determined by the amount of eccentricity of the eccentric gear 6. For example, when the size of the steel ball is large, it is necessary to shorten the inspection time. Therefore, the holder 5 and the eccentric gear 6 are designed so that the width of the meridian interval S can be widened. The holder 5 and the eccentric gear 6 are dedicated parts depending on the size of the steel ball.

  On the other hand, in FIG. 2, the appearance scratch inspection uses the same configuration as the first probe of the top coil system shown in FIG. After the appearance scratch inspection is completed, by providing a location where a steel ball determined to be non-defective can pass through the exciting coil 9 and the detection coil 10 shown in FIG. In one inspection apparatus, the appearance flaw inspection, the foreign material discrimination, and the quenching state judgment can be performed almost simultaneously.

  Note that the detection probes 7 and 8 use a mutual induction type self-comparison method in order to inspect the appearance of the rotating steel balls, or to inspect the foreign material discrimination and quenching state judgment device. This probe is composed of an exciting coil for passing an exciting current to induce eddy current and a detecting coil for detecting a change in eddy current. Then, in order to detect scratches, a high-frequency current of 0.6 MHz to 3 MHz is passed through the exciting coil as a first probe, and changes in eddy current flowing on the surface of the steel ball are detected. Further, in order to perform different material discrimination and quenching state determination, a current of a low frequency of 50 Hz to 1500 KHz, usually 5 KHz to 500 KHz is supplied to the exciting coil, and a change in voltage phase is detected using the second probe. At this time, when the penetrating coil system shown in FIG. 2B is used for the second probe, a low-frequency current is passed through the outer exciting coil 9, and the detection coil 10 passes through the passage 11 in the penetrating coil. The steel ball 1 determined to be non-defective by the first probe is inspected.

  For appearance scratch inspection, an oscilloscope is connected from the monitoring terminal of the inspection machine, and the sensitivity adjustment is performed by displaying a signal as shown in FIG. 4 using an artificially processed defect sphere.

  That is, since the noise a due to vibration of the rotating device and the steel ball and the signal b due to the reference defect have a phase with each other, the phase of the noise a is adjusted along the horizontal axis so as to improve the SN ratio by the phase detection circuit. Then, the reference defect sphere signal b projected onto the vertical axis is adjusted so as to have a predetermined magnitude. Then, the detection sensitivity is set by adjusting the magnitude and phase of the defect signal of the reference defect sphere, and a non-defective product or a defective product is determined by comparing the reference defect sphere with the inspection target sphere. At that time, the noise is removed from the received signal using a filter, and the scratch is detected by extracting only the scratch signal. In addition, regarding the different material discrimination and the quenching state determination, a signal as shown in FIG. 5 is displayed, and the change in voltage and phase of the inspection subject ball and the different material steel ball is compared using the reference sphere of the material to be inspected. , Dissimilar material discrimination and quenching state judgment are performed. At that time, the noise is removed from the signals received using the synchronous detection circuit, and only the signal synchronized with the test frequency is taken out, so that the different materials are discriminated and the quenching state is discriminated.

  FIG. 5 is a phase detection output screen of the inspection apparatus in the above-described different material discrimination and quenching state determination, showing the steel ball material signal, c in the figure, c is the SUJ2 product ball material signal, and d is the SUJ2 unheated ball. The material signal, e, is the material signal of the SUS440C product ball.

  Thus, with the above-described configuration, the steel ball rotates so as to draw a meridian locus in the inspection apparatus, and the appearance flaw inspection, foreign material determination, and quenching state determination of the entire surface are continuously performed.

It is a schematic diagram showing an example of an inspection device concerning the present invention. The outline | summary of the test | inspection apparatus of the other form which concerns on this invention is shown, (A) is a probe of a top coil system, (B) is a figure of a penetration coil system. It is a figure which shows the locus | trajectory on the steel ball which the probe (detection sensor) in this invention inspects. It is a figure which shows the phase detection circuit output screen of the test | inspection apparatus used for this invention in an external appearance crack test | inspection. It is a figure which shows the phase detection output screen of the test | inspection apparatus which this invention uses in different material discrimination | determination and quenching state determination.

Explanation of symbols

1: Steel ball 2: Drive motor 3: Support roller 4: Control roller 5: Holder 6: Eccentric gear 7: Scratch detection sensor (first probe)
8: Dissimilar material discrimination, quenching state judgment sensor (second probe)
9: Excitation coil 10: Detection coil 11: Passage a: Noise caused by vibration of rotating device and steel ball b: Defect signal c: Material signal of SUJ2 product ball d: Material signal of SUJ2 unheated ball e: Material of SUS440C product ball signal

Claims (3)

  A eddy current flaw detector that performs an external flaw inspection with a first probe of an upper coil type that passes a high frequency current, and a different material discrimination and quenching state that has a second probe of an upper coil type that passes a low frequency current An eddy current flaw detection device that performs judgment is built in one visual inspection device, and the first and second probes are installed in the vicinity of the steel ball. Appearance flaw inspection, different material discrimination and quenching are performed in one visual inspection device. A steel ball inspection device characterized by being able to inspect the state almost simultaneously.   A eddy current flaw detector that performs an external flaw inspection with a first probe of an upper coil type that passes a high-frequency current, and a different material discrimination and quenching state judgment that has a second probe of a through-coil type that passes a low-frequency current The eddy current flaw detection device is built in one visual inspection device, the first and second probes are installed in the vicinity of the steel ball, the visual flaw inspection, different material discrimination and quenching in one visual inspection device A steel ball inspection device characterized by the fact that it is possible to inspect almost simultaneously.   The steel ball inspection apparatus according to claim 1 or 2, wherein an alternating current having a high frequency of 0.6 MHz to 3 MHz and a low frequency of 50 Hz to 1500 KHz is used.

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