JP2017036918A - Surface characteristic inspection and separation device, surface characteristic inspection and separation system and surface characteristic inspection and separation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface characteristic inspection and separation device, a surface characteristic inspection and separation system and a surface characteristic inspection and separation method which efficiently perform processes to evaluate surface characteristics of spring members subjected to surface treatment, determine appropriateness thereof and separate defective members from non-defective members and thereby being suitably applied to inspection and separation of spring members having short takt time.SOLUTION: A surface characteristic inspection and separation device 1 is for evaluating surface characteristics of spring members M subject to surface treatment, determining appropriateness thereof and discharging the same after separating defective members from non-defective members. The surface characteristic inspection and separation device 1 comprises: a surface characteristic inspection device 2; a guide member 40 which guides each spring member M to an inspection detector 23; a measurement member 50 which measures the surface characteristics of the spring members M; a separation member 60 which separated the spring members M into non-defective members and defective members and discharges the same; rotation drive means 70 which rotates the measurement member 50; and a control device 80 which controls performance of the rotation drive means 70 and the separation member 60.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a surface property inspection / selection device for inspecting the quality of a surface treatment state of a spring-like member subjected to surface treatment such as shot peening treatment, heat treatment, nitriding treatment, etc., and sorting good products from defective products, surface property inspection The present invention relates to a sorting system and a surface property inspection sorting method.

Steel products such as gears, shafts, and springs are subjected to surface treatment such as heat treatment, surface hardening by nitriding treatment, and shot peening treatment in order to improve wear resistance and fatigue strength.
Conventionally, evaluation of surface characteristics such as residual stress and hardness after surface treatment of these products has been performed by sampling destructive inspection. For this reason, there are a problem that all products cannot be directly inspected, and a problem that inspection products cannot be used because of destructive inspection.
Therefore, there is an increasing demand for development of an apparatus capable of nondestructively inspecting the surface characteristics of products. As such an apparatus, for example, in Patent Document 1, an AC signal is input to a test circuit having a coil disposed above the shot peening processing surface while changing the frequency, and the frequency response characteristic of the impedance in the test circuit. A non-destructive inspection apparatus for a shot peening treatment surface for inspecting the state of occurrence of residual stress in an inspection object is disclosed.

JP 2008-2773 A

  Since the above-mentioned technique is a local measurement, the influence of heat generation due to the concentration of eddy current is likely to occur, and it takes a lot of time to inspect the entire surface treatment unit. Spring-like members such as valve springs require less time for surface treatment (tact time) than large members such as gears, so the time required for inspection of surface characteristics and selection between good and defective products is longer. As a result, there is a problem that the inspection / sorting process controls the entire process. In addition, no specific configuration has been proposed for efficiently sorting the spring-like member after a pass / fail judgment in a short time, and it takes a lot of time for sorting work, and efficient inspection and sorting are performed. There was a problem that could not.

  Therefore, the present invention evaluates the surface characteristics of a spring-like member that has been subjected to surface treatment such as shot peening treatment, heat treatment, nitriding treatment, etc., and performs an efficient process of judging whether it is good or bad and selecting good and defective products. An object of the present invention is to provide a surface characteristic inspection / selection device, a surface characteristic inspection / selection system, and a surface characteristic inspection / selection method that can be suitably applied to inspection / selection of a spring-like member having a short tact time.

In order to achieve the above object, the invention according to claim 1 is a surface property inspection and sorting device that evaluates the surface properties of a spring-like member that has been subjected to surface treatment and sorts non-defective products and defective products, An AC bridge circuit; an AC power supply that supplies AC power to the AC bridge circuit; and an evaluation device that evaluates surface characteristics of a spring-like member based on an output signal from the AC bridge circuit, the AC bridge circuit Can be arranged to excite eddy currents in a spring-like member with a variable resistor configured to vary the distribution ratio between the first resistor and the second resistor, and a coil capable of exciting AC magnetism And a reference detector for detecting a reference state as a reference to be compared with an output from the inspection detector, the first resistor, the second resistor, and the reference detection And the inspection detector The evaluation device is configured such that AC power is supplied to the AC bridge circuit, the inspection detector detects an electromagnetic characteristic of the spring-like member, and the reference detector detects a reference state. A surface characteristic inspection device for evaluating surface characteristics of the spring-like member based on an output signal from the AC bridge circuit in a state; a measuring member on which a plurality of the inspection detectors are arranged; and a surface of the spring-like member A guide member provided with a guide portion for guiding a spring-like member conveyed from a surface treatment apparatus for processing to a measurement position of an inspection detector provided with the measurement member, and the surface characteristics of the measurement member were evaluated. A sorting member that sorts a later spring-like member into a non-defective product and a defective product, and the measuring member is configured to be able to transport the spring-like member from the guide member to the sorting member, and the measuring member While conveying the spring-like member from the guide member to the sorting member, determines evaluate quality of the surface characteristics of the spring-like member by the surface properties testing device used technical means of.

According to the first aspect of the present invention, the eddy current is excited in the spring-like member by the coil of the inspection detector, and the surface characteristic of the spring-like member is evaluated based on the output signal output from the AC bridge circuit. it can. Thereby, it is possible to inspect the surface state with high accuracy with a simple circuit configuration.
Further, the spring member can be reliably guided to the measurement position of the inspection detector by the guide member. The measuring member evaluates the surface characteristics of the spring-like member by a surface characteristic inspection device while the spring-like member is conveyed from the guide member to the sorting member, and determines whether the spring-like member is good or bad. It can be used for the time to evaluate and judge the quality. Thereby, evaluation of the surface characteristic of a spring-like member and judgment of quality can be performed corresponding to a short tact time. The spring-like member can be reliably sorted into a non-defective product and a defective product by the sorting member.
The surface characteristic means “characteristic from the outermost surface of the spring-like member to the influence layer on the inner surface”.

  According to a second aspect of the present invention, in the surface property inspection / sorting apparatus according to the first aspect, the measurement member includes a plurality of the inspection detectors arranged concentrically and intersects with a conveying direction of the spring-like member. In the sorting member, a non-defective product outlet for carrying out a spring-like member determined to be a non-defective product by the surface property inspection and sorting device, and a defective product by the surface property inspection and sorting device. A defective product outlet for unloading the determined spring-like member, and provided side by side in the direction opposite to the rotational direction of the measurement member as viewed from the guide portion of the guide member, The technical means that the spring-like member is provided with selection means for selecting whether to carry out the non-defective product exit or the defective product exit is used.

  If the surface characteristic inspection and sorting apparatus is configured as in the invention described in claim 2, the apparatus can be reduced in size.

  According to a third aspect of the present invention, in the surface characteristic inspection / selection device according to the first or second aspect, the guide member is formed in communication with the guide portion and stores the conveyed spring-like member. The technical means of further comprising a storage member is used.

  According to the third aspect of the present invention, since the guide member is provided with the storage member that stores the spring-like member conveyed, the timing of storing the spring-like member with the storage member and sending the spring-like member to the measurement member. Therefore, it is possible to cope with fluctuations in the timing at which the spring-like member is conveyed.

  According to a fourth aspect of the present invention, there is provided a surface characteristic inspection / sorting system according to any one of the first to third aspects, and a spring subjected to surface treatment by the surface treatment apparatus. A technical means is provided that includes a conveying means for conveying the shaped member to the surface characteristic inspection and sorting apparatus.

  By combining the surface characteristic inspection / sorting device and the conveying means for conveying the spring-like member subjected to the surface treatment by the surface treatment device to the surface characteristic inspection device as in the invention described in claim 4, It is possible to construct a surface property inspection / selection system that can continuously carry, evaluate, sort, and carry out members.

  According to a fifth aspect of the present invention, there is provided the surface characteristic inspection / selection system according to the fourth aspect, wherein the non-defective product transport means for transporting the spring-like member selected and judged as a non-defective product and selected as a defective product. The technical means is further provided with a defective product recovery means for recovering the spring-like member.

  According to the invention described in claim 5, the non-defective product can be quickly transported to the next process by the non-defective product transporting means, and only the defective products can be sorted and collected by the defective product collecting means. Can be performed efficiently.

  According to a sixth aspect of the present invention, in the surface characteristic inspection / selection system according to the fourth aspect, the conveying means includes a conveying belt, and a partition member that divides a position of the conveying belt on which the spring-like member is placed. The technical means of providing is used.

  As in the sixth aspect of the invention, by partitioning the transport belt of the transport means by the partition member, the spring-shaped member can be transported reliably one by one at a predetermined timing. In addition, it is not necessary to provide a member for storing the spring-like member before placing it on the surface characteristic inspection and sorting device, and the device can be simplified.

According to a seventh aspect of the present invention, there is provided a surface characteristic inspection / selection device according to any one of the first to third aspects, wherein the surface characteristic inspection / selection apparatus is prepared, surface-treated by the surface treatment apparatus and conveyed. A spring-like member is disposed at the measurement position of the inspection detector via the guide member, the spring-like member is transported to the sorting member, and surface characteristics are evaluated until reaching the sorting member, A technical means is used in which the quality is determined by a surface characteristic inspection device, and the spring-like member is classified into a non-defective product and a defective product based on the quality determination by the surface characteristic inspection device.

  According to the seventh aspect of the present invention, it is possible to reliably guide the spring-like member to the measurement position of the inspection detector by the guide member using the surface characteristic inspection / selection device. Further, while the measurement member is transporting the spring-like member from the guide member to the sorting member, the surface property inspection apparatus evaluates the surface property of the spring-like member and determines whether it is acceptable. It can be used for the time to evaluate the surface characteristics and judge the quality. Thereby, evaluation of the surface characteristic of a spring-like member and judgment of quality can be performed corresponding to a short tact time. The spring-like member can be reliably sorted into a non-defective product and a defective product by the sorting member.

It is explanatory drawing which shows the structure of a surface characteristic test | inspection selection apparatus. 1A is a front view, and FIG. 1B is a partially transparent side view showing the internal structure of the cross section taken along the line AA of FIG. 1A. It is a transparent explanatory drawing which shows the structure of the test | inspection detector of the surface characteristic test | inspection apparatus arrange | positioned at a measurement member. It is explanatory drawing which shows the structure of a surface characteristic test | inspection selection system. It is explanatory drawing explaining the process of the surface characteristic test | inspection selection method. It is explanatory drawing which shows the circuit structure of a surface characteristic inspection apparatus. It is an equivalent circuit diagram explaining the output from an AC bridge circuit. It is a flowchart which shows the surface characteristic inspection method. It is a partially transparent side view which shows the example of a change of a surface characteristic test | inspection selection apparatus. It is a partially transparent side view which shows the example of a change of a surface characteristic test | inspection selection apparatus. It is a front view which shows the example of a change of a surface characteristic inspection selection device.

The surface property inspection / sorting device 1 is subjected to surface treatment by a surface treatment device such as a shot peening device, evaluates the surface property of the spring-like member M conveyed by the conveying means, determines pass / fail, and based on the determination result. This is a device that sorts out good products and defective products. As shown in FIG. 1, the surface property inspection / selection device 1 includes a surface property inspection device 2 to be described later and the spring-like member M to the inspection detector 23 from upstream to downstream in the conveying direction of the spring-like member M. A guiding member 40 for guiding, a measuring member 50 for measuring the surface characteristics of the spring-like member M, a sorting member 60 for sorting the spring-like member M into a non-defective product and a defective product, and a measuring member 50 are rotated. A rotation driving means 70 and a control device 80 for controlling the operations of the rotation driving means 70 and the sorting member 60 are provided. Here, in FIG. 1 (B), the surface characteristic inspection device 2, the rotation drive means 70, and the control device 80 are schematically shown instead of sectional views.

The guide member 40 and the sorting member 60 are integrally provided by the outer cylinder 90 and fixed so as not to rotate by the rotation driving means 70 or the like.

In the measurement member 50, a plurality of inspection detectors 23 provided in the surface property inspection apparatus 2 are arranged on a concentric circle at equal intervals. The measuring member 50 is connected to the rotation shaft 71 of the rotation driving means 70 and is configured to be rotatable with respect to the guide member 40 and the sorting member 60 so as to intersect the conveying direction of the spring-like member M.

As shown in FIG. 2, the inspection detector 23 includes a cylindrical core 23a formed so as to cover the entire spring-like member M, and a coil 23b wound around the outer peripheral surface of the core 23a. . The core 23a is made of a non-magnetic material, for example, resin, and has a dimension that allows the spring-like member M to be disposed at a predetermined measurement position simply by inserting the spring-like member M.

Each of the plurality of inspection detectors 23 constitutes a circuit shown in FIG. Here, the evaluation device 30 can share one evaluation device 30.

Since the inspection detector 23 is characterized in that the surface characteristics are evaluated by capturing the reaction of the eddy current with high accuracy, the inspection detector 23 is arranged with respect to the spring-like member M so that the eddy current flows in the region where the surface characteristics are to be inspected. It is preferable to do. That is, it is preferable to arrange the coil 23b so that the winding direction is the same as the direction in which the eddy current flows. The coil 23b may be arranged so that the winding direction of the coil 23b is substantially orthogonal to the axis of the spring-like member M. Thereby, since a magnetic field loop is generated in the winding direction of the spring-like member M, an eddy current can be excited efficiently, and the surface characteristics of the entire spring-like member M can be inspected at a time.

Here, a configuration in which eight inspection detectors 23 (23A-23H) are provided on the measurement member 50 will be described as an example. The inspection detectors 23A-23H are sequentially arranged counterclockwise as viewed from the upstream side. A position where the inspection detectors 23A-23H are initially arranged is defined as A1-A8 clockwise from the inspection detector 23A. Here, A1 is an arrangement position at which the spring-like member M is arranged on the inspection detector 23, A2-A6 is a measurement section, and A7 and A8 are selection positions for selection.

The guide member 40 is provided with a guide portion 41, which is a through hole for guiding the spring-like member M to the inspection detector 23, corresponding to the arrangement position A <b> 1 of the spring-like member M.

The sorting member 60 has a non-defective product outlet 61 formed as a through-portion for unloading the spring-like member M determined as a non-defective product to the sorting position A7, and a penetration for unloading the spring-shaped member M determined to be a non-defective product to the sorting position A8. A defective product outlet 62 formed as a section. Moreover, the shutter 63 comprised so that the opening part 61a by the side of the measurement member 50 of the good quality goods exit 61 could be opened and closed is provided. The shutter 63 acts as a selection member that selects whether the spring-like member M is carried out from the non-defective product carrying-out port 61 or the defective product carrying-out port 62. FIG. 1 shows a state where the shutter 63 is closed and the opening 61a of the non-defective product outlet 61 is closed.

The rotation driving means 70 uses a stepping motor, a servo motor or the like that can rotate the measuring member 50 and stop at a predetermined position.

The control device 80 controls the rotation driving means 70 to rotate the measurement member 50 and control the position of the inspection detector 23. The control device 80 is connected to the determination unit 36 of the surface characteristic inspection device 2 and controls the operation of the shutter 63 based on the determination result of the surface treatment state of the spring-like member M in the determination unit 36.

  As shown in FIG. 3, the surface characteristic inspection / selection apparatus 1 includes a conveying means 100 and a selection member 60 that convey the spring-like member M processed by a surface treatment apparatus such as a peening apparatus toward the surface characteristic inspection / selection apparatus 1. In combination with the non-defective product conveying means 110 for conveying the spring-shaped member M selected as a non-defective product, the defective product collecting means 120 for recovering the spring-shaped member M selected as a non-defective product by the selecting member 60, etc. Can be configured. Here, the surface characteristic inspection / selection apparatus 1 is installed so that the guide member 40, the measurement member 50, and the selection member 60 are inclined to face the conveying direction so that the spring-like member M can move inside by its own weight. Yes. FIG. 3 illustrates a state in which the shutter 63 is opened and the opening 61a of the non-defective product outlet 61 is opened.

As the conveyance means 100, a plurality of pins 102, which are division members that divide the position where the spring-like member M is placed on the conveyance belt 101 and the conveyance belt 101, are provided, and between the adjacent pins 102 and 102. The structure which arrange | positions and conveys the spring-like member M one by one can be used suitably. Thereby, the spring-like member M can be reliably conveyed one by one at a predetermined timing. Further, it is not necessary to provide a member for storing the spring-like member M before placing it on the surface property inspection / sorting apparatus 1, and the apparatus can be simplified. A slope 103 is provided at the position where the conveyor belt 101 is reversed to guide the spring-like member M to the surface characteristic inspection / sorting device 1 located below.

The non-defective product conveying means 110 is constituted by a belt conveyor or the like, and is provided below the non-defective product outlet 61. The defective product collecting means 120 is configured by a storage box or the like for storing defective products, and is provided below the defective product outlet 62.

According to such a surface characteristic inspection / selection system S, since the conveyance means 100 is provided, it is constructed as a surface characteristic inspection / selection system capable of continuously carrying, evaluating, selecting, and carrying out the spring-like member M. be able to. In addition, the non-defective product transporting unit 110 can quickly transport the non-defective product to the next process, and the defective product collecting unit 120 can select and collect only defective products, so that the sorting operation can be performed efficiently. it can.

  Next, a surface property inspection / selection method for selecting the spring-like member M into a non-defective product and a defective product using the surface property inspection / selection apparatus 1 will be described. For simplicity, the shutter 63 and the outer cylinder 90 are not shown in FIG.

As shown in FIG. 4A, the measurement member 50 is stopped in a state where the inspection detector 23A is at the arrangement position A1. First, the spring-like member M1 conveyed by the conveyance belt 101 slides down the slope 103 and is guided by the guide member 40 to the inspection detector 23A at the arrangement position A1 via the guide portion 41.

Subsequently, when the rotation driving means 70 is driven to move the inspection detector 23A to the position A2 of the measurement section, the spring-like member M1 moves to A2 together with the inspection detector 23A as shown in FIG. 4B. To do. The inspection detector 23B faces the guide portion 41, and the spring-like member M2 is guided to the inspection detector 23B at the spring-like member M arrangement position A1 by the guide member.

By repeating the above operation at regular time intervals in accordance with the conveyance timing of the spring-like member M, the spring-like member M1 moves to the measurement section position A6 together with the inspection detector 23A as shown in FIG. At this time, the inspection detector 23B is the measurement section position A5, the inspection detector 23C is the measurement section position A4, the inspection detector 23D is the measurement section position A3, the inspection detector 23E is the measurement section position A2, and the inspection detector. Reference numeral 23F denotes an arrangement position A1, and guided spring-like members M2-M6 are arranged therein. During the movement of the spring-like member M1 from the arrangement position A1 to the position A6 of the measurement section, the surface characteristic is evaluated by the surface characteristic inspection apparatus 2, and the quality is determined. Here, a sensor such as a photoelectric sensor is provided on the guide member 40 or the measurement member 50, and it is detected by this sensor that the spring-like member M is disposed on the measurement member 50, and the measurement member 50 is based on the detection signal. Can also be rotated. According to this, the spring-like member M can be arranged on the measuring member 50 more reliably.

First, a case where the spring-like member M1 is determined to be a non-defective product will be described. FIG. 3 schematically shows a case where the spring-like member M1 is determined to be a non-defective product. When the spring-like member M1 is determined to be a non-defective product, the determination result is input to the control device 80 by the determination means 36 of the surface property inspection apparatus 2. When the inspection detector 23A is moved to the selection position A7 by the rotation driving means 70, the control device 80 opens the shutter 63 based on the determination result. As a result, the inspection detector 23 </ b> A and the non-defective product outlet 61 communicate with each other, so that the spring-like member M <b> 1 is carried out to the outside via the non-defective product outlet 61, and the non-defective product transport means 110 provided below the non-defective product outlet 61. Is transferred to the next process.

When the spring-like member M1 is determined to be defective, the determination unit 36 inputs a determination result to the control device 80. When the inspection detector 23A is moved to the selection position A7 by the rotation driving means 70, the control device 80 maintains the shutter 63 in a closed state based on the determination result. Thereby, the spring-like member M1 is not carried out of the inspection detector 23A but is held at the sorting position A7. Subsequently, when the inspection detector 23A is moved to the selection position A8 by the rotation driving means 70, the inspection detector 23A and the defective product outlet 62 communicate with each other, so that the spring-like member M1 passes through the defective item outlet 62. The defective product collecting means 120 provided below the defective product outlet 62 collects the product.

Since the above operation is continuously performed, the surface characteristics of the spring-like member M can be continuously evaluated to determine whether the spring-like member M is good or bad, and the spring-like member M can be classified into a good product and a defective product.

  According to the surface characteristic inspection / separation apparatus 1, the spring-like member M can be reliably guided to the measurement position of the inspection detector 23 by the guide member 40. The measurement member 50 evaluates the surface characteristics of the spring-like member M by the surface characteristic inspection apparatus 2 and judges whether or not the spring-like member M is transferred from the guide member 40 to the sorting member 60. It can be used for the time for evaluating the surface characteristics of the spring-like member M and judging the quality. Thereby, it is possible to evaluate the surface characteristics of the spring-like member M and judge whether it is good or bad, corresponding to a short tact time. The sorting member 60 can reliably sort the spring-like member M into a non-defective product and a defective product.

  The number of inspection detectors 23 and the rotation timing of the measurement member 50 can be set as appropriate in accordance with the tact time and the inspection time. For example, if the transport timing is 1 second and it takes 3 seconds for the inspection and pass / fail judgment, it is only necessary to provide three inspection detectors 23 in the measurement section. It can be set as the structure which provided the six test | inspection detectors 23 which added the number.

(Surface characteristic inspection equipment)
Next, a detailed configuration of the surface property inspection apparatus 2 will be described. As shown in FIG. 5, the surface property inspection apparatus 2 according to the embodiment of the present invention includes an AC power supply 10, an AC bridge circuit 20, and an evaluation apparatus 30.

  The AC power supply 10 is configured to be able to supply AC power having a variable frequency to the AC bridge circuit 20.

  The AC bridge circuit 20 includes a variable resistor 21 and a test detector 23 formed so that a coil can be arranged so as to excite eddy currents in the spring-like member M, and a reference state that is a reference for comparison with the output from the test detector 23. A reference detector 22 is provided.

The variable resistor 21 is configured such that the resistor _RA can be variably distributed between the resistor R1 and the resistor R2. The resistors R1 and R2 form a bridge circuit together with the reference detector 22 and the inspection detector 23. In the present embodiment, a point A that distributes the resistor R1 and the resistor R2 and a point B between the reference detector 22 and the inspection detector 23 are connected to the AC power supply 10 of the evaluation device 30, and the resistor R1 and the reference detector are connected. The point C between 22 and the point D between the resistor R 2 and the test detector 23 is connected to the amplifier 31. In addition, the reference detector 22 and the inspection detector 23 are grounded to reduce noise.

  The evaluation device 30 includes an amplifier 31 that amplifies the voltage signal output from the AC bridge circuit 20, an absolute value circuit 32 that performs full-wave rectification, a low-pass filter (LPF) 33 that performs DC conversion, and an AC supplied from the AC power supply 10. A phase comparator 34 that compares the phase of the voltage with the voltage output from the amplifier 31, a frequency adjuster 35 that adjusts the frequency of the AC voltage supplied from the AC power supply 10, and an unbalance adjustment that optimizes the distribution of R1 and R2. And a display means 37 for determining whether the surface state of the spring-like member M is good or not based on an output from the LPF 33, a display means 37 for displaying and warning the determination result by the determination means 36, and a temperature for detecting the temperature of the evaluation position Measuring means 38 is provided.

  The amplifier 31 is connected to the point C and the point D, and a potential difference between the point C and the point D is input. Further, the absolute value circuit 32 and the LPF 33 are connected to the determination means 36 in this order. The phase comparator 34 is connected to the AC power supply 10, the amplifier 31, and the determination unit 36. The frequency adjuster 35 is connected to the AC power supply 10 and the amplifier 31. The judging means 36 is configured to change the position of the point A of the AC bridge circuit 20, that is, the distribution ratio γ between the resistors R1 and R2 by outputting a control signal. Thus, a variable resistance setting step described later is executed.

The temperature measuring unit 38 is composed of a non-contact infrared sensor, a thermocouple, or the like, and outputs a temperature signal on the surface of the spring-like member M to the determining unit 36. When the temperature of the spring-like member M detected by the temperature measuring means 38 is within a predetermined range, the judging means 36 judges whether or not the surface treatment state of the spring-like member M is good and is detected by the temperature measuring means 38. When the temperature is outside the predetermined range, the quality of the surface treatment state of the spring-like member M is not judged. Accordingly, when the temperature of the spring-like member M affects the accuracy of the inspection, it is possible to prevent the determination of the quality of the surface treatment state of the spring-like member from being performed. Can do. Here, the temperature of the evaluation position Ts is measured with a thermocouple or the like, and a determination is made as to whether or not the quality of the surface treatment state of the spring-like member M is judged as a temperature representative of the surface temperature of the spring-like member M. Can also be adopted.

As the inspection detector 23 and the reference detector 22 having the same configuration as the inspection detector 23, a coil is wound around the outer periphery of the core through which the evaluation part of the spring-like member can be inserted. A detector capable of exciting an eddy current in the spring-like member M is used while being opposed to the surface. That is, this coil is wound so as to face the surface characteristic inspection region of the spring-like member. Here, surrounding the surface property inspection region of the spring-shaped member includes exciting eddy currents in the surface property inspection region by surrounding at least a part of the surface property inspection region. I mean.

  When the inspection detector 23 is arranged so that the coil 23b faces the inspection target surface of the spring-like member M and AC power having a predetermined frequency is supplied from the AC power source 10 to the coil 23b, an AC magnetic field is generated, and the spring-like shape is generated. Eddy currents flowing in the direction crossing the alternating magnetic field are excited on the surface of the member M. Since the eddy current changes according to the electromagnetic characteristics of the residual stress layer, the phase and amplitude (impedance) of the output waveform (voltage waveform) output from the amplifier 31 change according to the characteristics (surface treatment state) of the residual stress layer. To do. The change in the output waveform can detect and inspect the electromagnetic characteristics of the surface treatment layer.

A magnetic shield 23c disposed outside the inspection detector 23 and surrounding the spring-like member M may be provided. When the magnetic shield 23c is used, the external magnetism can be shielded, so that the detection sensitivity of electromagnetic characteristics can be improved, and the detection sensitivity of electromagnetic characteristics corresponding to the surface treatment state is improved. The surface treatment state can be evaluated with higher accuracy.

(Output from AC bridge circuit)
Next, the output from the AC bridge circuit 20 adjusted to a non-equilibrium state will be described with reference to the equivalent circuit of FIG. For example, a reference specimen S that is guaranteed to have a good surface treatment state is brought close to the reference detector 22, and whether or not the surface treatment state is good should be judged to the inspection detector 23. The spring-like member M is in close proximity. Here, a configuration in which the reference sample S is not brought close to the reference detector 22, that is, the reference sample S is not used may be employed. The output when the reference sample S is used will be described below. However, when the reference sample S is not used, the description is omitted because it is the same except that iα described later becomes 0. In the surface property inspection method described later, a configuration in which the reference sample S is not used will be described.

When the distribution ratio of the variable resistor _RA is γ, the resistor R1 is R _A / (1 + γ), and the resistor R2 is R _A γ / (1 + γ). Assume that the impedance of the reference detector 22 is R _S + jωL _S , and the impedance of the inspection detector 23 is R _T + jωL _T. Further, the potential at the point A is set to E, and the excitation current flowing through each side of the bridge when the respective specimens (reference specimen S and spring-like member M) are not in proximity to the reference detector 22 and the test detector 23 is i. ₁ , i ₂ , the amount of magnetism changes by bringing each specimen close to the reference detector 22 and the test detector 23, and currents flowing in accordance with the amount of change are iα and iβ, respectively. At this time, the potentials E1 and E2 and the excitation currents i ₁ and i ₂ of the reference detector 22 and the inspection detector 23 are expressed by the following equations (1) to (4).

  The voltage output to the amplifier 31 is the difference between E1 and E2, and is expressed by the following equation.

  The following equations are derived from equations (3) to (5).

成分Ｂ
：

The right side of Equation (6) is divided into the following components A and B, and each component of the differential voltage is considered.
Ingredient A:

Component B
:

The component A is composed of detector components: (R _S + jωL _S ), (R _T + jωL _T ), and current amounts that change when each specimen approaches the detectors: iα, iβ. The magnitudes of iα and iβ vary depending on the amount of magnetism passing through the specimen due to electromagnetic characteristics such as the magnetic permeability and conductivity of each specimen. Therefore, the magnitudes of iα and iβ can be changed by changing the excitation currents i ₁ and i ₂ that influence the amount of magnetism generated from each detector. Further, from the expressions (3) and (4), the excitation currents i ₁ and i ₂ change depending on the distribution ratio γ of the variable resistance. Therefore, the magnitude of the component A is changed by adjusting the distribution ratio γ of the variable resistance. be able to.

The component B is composed of each detector component: (R _S + jωL _S ), (R _T + jωL _T ), and a resistance parameter divided by a variable resistance distribution ratio γ. For this reason, similarly to the component A, the size of the component B can be changed by adjusting the distribution ratio γ of the variable resistor.

  When the spring-like member M is disposed at a predetermined position and AC power having a predetermined frequency is supplied from the AC power source 10 to the coil 23b of the inspection detector 23, a vortex that flows in the direction intersecting the AC magnetic field on the surface of the spring-like member M. Current is excited. Since the eddy current changes according to the electromagnetic characteristics of the residual stress layer, the phase and amplitude (impedance) of the output waveform (voltage waveform) output from the amplifier 31 change according to the characteristics (surface treatment state) of the residual stress layer. To do. The electromagnetic characteristics of the residual stress layer can be detected by the change in the output waveform, and the surface treatment state can be inspected.

A signal output from the amplifier 31 of the bridge is a signal obtained by extracting a difference area between the voltage waveforms of the reference detector 22 and the inspection detector 23, and has a circuit configuration that makes a current (excitation current) flowing through the detector constant. Therefore, the extracted voltage signal can be considered as a power signal. Further, the power supplied to the detector is always constant, and the magnetic energy supplied to the spring-like member M can also be constant.

(Surface characteristic inspection method)
Next, a method for inspecting the surface property of the spring-like member M by the surface property inspection apparatus 2 will be described with reference to FIG.

  First, in the preparation step S1, a surface characteristic inspection device 2 and a reference sample S with good surface treatment are prepared. In addition, a reference sample that is a sample that has not been subjected to surface treatment or a sample that has a poor surface treatment state may be prepared.

Next, a variable resistance setting step S2 is performed. In the variable resistance setting step S <b> 2, first, AC power is supplied from the AC power supply 10 to the AC bridge circuit 20. In this state, the distribution ratio γ of the variable resistor 21 is adjusted so that the detection sensitivity of the specimen by the surface characteristic inspection apparatus 2 is increased. That is, the distribution ratio γ of the variable resistor 21 is adjusted so that the output signal of the AC bridge circuit 20 becomes small without bringing the specimen close to the test detector 23. By setting the variable resistor 21 in this way, the difference in output signal between the case where the surface treatment state of the spring-like member M close to the inspection detector 23 is poor and the case where the surface treatment state is good. The detection accuracy can be increased. Specifically, the voltage amplitude of the output signal from the AC bridge circuit 20 or the voltage output from the LPF 33 is monitored and output by a display device having a waveform display function such as an oscilloscope (for example, provided in the determination unit 36). The distribution ratio γ is adjusted so that becomes smaller. Preferably, the distribution ratio γ of the variable resistor 21 is adjusted and set so that the output takes the minimum value or the minimum value (local equilibrium point).

Adjustment of the distribution ratio γ of the variable resistor 21 is performed in order to increase the output difference according to the difference in the surface state by reducing the differential voltage (E2−E1), and to improve the inspection accuracy. As described above, since the components A and B change by adjusting the distribution ratio γ, they are variable according to the impedances (R _S + jωL _S ) and (R _T + jωL _T ) of the reference detector 22 and the test detector 23. By adjusting the distribution ratio γ of the resistor 21, the differential voltage (E2-E1) that is the output from the AC bridge circuit 20 can be reduced. Thus, the difference in characteristics between the reference detector 22 and the inspection detector 23 can be reduced, and the original characteristics of the spring-like member M can be extracted as much as possible, so that the inspection accuracy can be improved.

  In the frequency setting step S <b> 3, AC power is supplied from the AC power supply 10 to the AC bridge circuit 20 with the reference sample S being close to the test detector 23, and supplied to the AC bridge circuit 20 by the frequency adjuster 35. The voltage amplitude output from the AC bridge circuit 20 or the voltage output from the LPF 33 is monitored.

The frequency adjuster 35 outputs a control signal to the AC power supply 10 so that the initial frequency f1 set in the frequency adjuster 35 is obtained, and the output voltage Ef1 from the amplifier 31 at the frequency f1 is input to the frequency adjuster 35. Remembered. Subsequently, a control signal is output to the AC power supply 10 so that the frequency f2 becomes a predetermined value, for example, 100 Hz higher than the frequency f1, and the output voltage Ef2 from the amplifier 31 at the frequency f2 is input to the frequency regulator 35 and stored. Is done. Subsequently, Ef1 and Ef2 are compared, and if Ef2> Ef1, a control signal is output so that the frequency f3 is a predetermined value higher than the frequency f2, and the output voltage Ef3 from the amplifier 31 at the frequency f3 is It is input to the frequency adjuster 35 and stored. Then, Ef2 and Ef3 are compared. This is repeated, and the frequency fn when Efn + 1 <Efn, that is, the frequency fn at which the output is maximized, is set as the frequency used in the threshold setting step S4 and the AC supply step S5. Thereby, the frequency which makes the output from the AC bridge circuit 20 large corresponding to the spring-like member M having different surface treatment state, shape, etc. and different impedance can be set by one operation. The optimum frequency varies depending on the material, shape, and surface treatment state of the spring-like member. However, if this is known in advance, it is not necessary to set the frequency. Thereby, an output respond | corresponds sensitively to the change of a surface treatment state, and the sensitivity of a test | inspection can be improved.
Here, frequency setting process S3 can also be implemented prior to variable resistance setting process S2. Further, when the reference sample S is used, an optimum frequency can be selected and the original characteristics of the spring-like member M can be extracted as much as possible. However, the frequency is set using the reference sample instead of the reference sample S. You can also

  In the threshold setting step S4, the reference specimen S is brought close to the test detector 23, and AC power having the frequency set in the frequency setting step S3 is supplied from the AC power source 10 to the AC bridge circuit 20. The voltage output output from the AC bridge circuit 20 is amplified by the amplifier 31, is subjected to full-wave rectification in the absolute value circuit 32, is subjected to DC conversion in the LPF 33, and is output to the determination means 36. The output value output to the determination means 36 when the reference sample S with good surface treatment is brought close to the test detector 23 is set as a normal threshold value and stored in the determination means 36. Here, by setting the output value output to the determination means 36 when the reference specimen is brought close to the test detector 23 as a defect threshold value and increasing the threshold value, the convenience of the test can be improved. it can.

  In the quality determination step S8 described later, the output value when the spring-shaped member M is brought close to the inspection detector 23 is compared with the normal threshold value and the defective threshold value, and the quality of the spring-shaped member M is determined. In this case, when the output value of the spring-like member M is a value between the normal threshold value and the defective threshold value, the quality cannot be determined. Therefore, it is possible to perform output measurement using a plurality of reference specimens having different surface states, and to set the failure threshold value so that the difference from the normal threshold value becomes small. Further, the failure threshold value may be determined more precisely by using the spring-like member destructive inspection together.

In the AC supply step S5, AC power having the frequency set in the frequency setting step S3 is supplied from the AC power source 10 to the AC bridge circuit 20. Here, the reference sample S is not close to the test detector 23.

  Next, in the arranging step S6, the spring-like member M to be judged as to whether the surface treatment state is good is brought close to the inspection detector 23 and arranged so that eddy current is excited in the spring-like member. At this time, a voltage output signal is output from the AC bridge circuit 20, the output signal is amplified by the amplifier 31, is full-wave rectified in the absolute value circuit 32, and is converted into DC by the LPF 33.

  The temperature measuring means 38 measures the temperature of the surface of the spring-like member M before the spring-like member M approaches the inspection detector 23 or after the placement of the spring-like member M, and outputs the temperature signal of the surface of the spring-like member M. It outputs to the judgment means 36.

  In the inspection state determination step S7, the phase comparator 34 compares the AC power waveform supplied from the AC power supply 10 with the AC voltage waveform output from the AC bridge circuit 20, and detects the phase difference between them. By monitoring this phase difference, it can be determined whether or not the inspection state is good (for example, there is no positional deviation between the inspection detector 23 and the spring-like member M). Even if the output from the AC bridge circuit 20 is the same, if the phase difference changes greatly, it can be determined that there is a change in the inspection state and there is a possibility that the inspection is not performed properly. Further, when the temperature of the spring-like member M detected by the temperature measuring means 38 is within a predetermined range, the judging means 36 judges whether or not the surface treatment state of the spring-like member M is good, and the temperature measuring means 38 detects it. When the measured temperature is outside the predetermined range, the quality of the surface treatment state of the spring-like member M is not judged. Here, the predetermined temperature range is a temperature range in which the temperature change of the spring-like member M does not substantially affect the inspection, and can be set to 0 to 60 ° C., for example. When the temperature of the surface of the spring-like member M is outside the predetermined temperature range, the apparatus waits until the spring-like member M is within the predetermined temperature range, and blows air to the spring-like member M. It is possible to move to another line without performing the inspection.

In the pass / fail judgment step S8, the signal DC-converted in the LPF 33 is inputted to the judgment means 36, and the judgment means 36 judges the quality of the surface state of the spring-like member M based on the inputted signal. That is, this process is an evaluation process for evaluating the surface characteristics of the spring-like member based on the output signal output from the AC bridge circuit 20. The determination result by the determination means 36 is output to the control device 80 of the surface characteristic inspection / selection device 1. Moreover, it can display by the display means 37 and can also warn when a surface-like body is unsatisfactory.

  Whether the surface treatment state of the spring-like member M is good or bad is determined by comparing the output value (measured value) from the LPF 33 with the normal threshold value set in the threshold value setting step S4. When a failure threshold value is set, an output value (measured value) from the LPF 33 is compared with a normal threshold value and a failure threshold value.

  Through the above steps, the quality of the surface treatment state of the spring-like member M can be inspected easily and with high accuracy. In order to continuously inspect the spring-like member M, the placement step S6, the inspection state determination step S7, and the pass / fail determination step S8 are repeatedly performed. When changing the type of the spring-like member M, the type of surface treatment, etc., the variable resistance setting step S2, the frequency setting step S3, and the threshold value setting step S4 are performed again.

  The inspection detector 23 captures a change in surface resistance indirectly by capturing a change in eddy current flowing on the surface of the spring-like member M. Here, when shot peening treatment is performed as surface treatment, the factors that cause the flow rate of eddy current to change include distortion due to shot peening, microstructure miniaturization, and dislocation. It is almost constant at about 0 ° C. to 40 ° C.). The magnetic change detected by the inspection detector 23 is due to a change in the demagnetizing field of the eddy current, and the cause of the change in the eddy current is less affected by the temperature change in the measurement environment. The influence of can be reduced. In order to detect a reference state in the reference detector 22, a reference sample S for outputting a reference output can also be used. According to this, for example, if the reference sample S having a good surface treatment state is used, the quality of the surface state of the spring-like member M can be evaluated in comparison with the reference sample S.

  When the inspection state determination step S <b> 7 is not performed, the surface characteristic inspection apparatus 2 can omit the phase comparator 34. For example, the positional relationship between the inspection detector 23 and the spring-like member M is detected by position detection means such as a laser displacement meter, and the deviation between the axis of the inspection detector 23 and the axis of the spring-like member M is within a predetermined range. It can be set as the structure which performs determination etc. with a photoelectric sensor (laser) etc. or not. Further, the phase comparator 34, the frequency adjuster 35, or the display means 37 can be provided integrally, for example, by being incorporated in the determination means 36.

  When the output from the AC bridge circuit 20 at the time of measuring the spring-like member M is sufficiently large, the variable resistance setting step S2 and the frequency setting step S3 can be omitted. When the frequency setting step S3 is omitted, the surface characteristic inspection apparatus 2 can omit the frequency adjuster 35.

(Example of change)
In the embodiment shown in FIG. 3, the spring-like member M is transported to the surface property inspection / sorting device 1 via the slope 103, but the method of transporting the spring-like member M to the surface property inspection / sorting device 1 is limited to this. It is not a thing. For example, it is possible to employ a configuration in which the surface characteristic inspection / sorting device 1 is disposed below the end of the conveyor belt 101 and the spring-like member M that falls is received by the guide member 40. In this case, as shown in FIG. 8, a guide member 40 including a guide portion 41 that opens wide upward can be suitably used. Here, the cross section in FIG. 8 corresponds to the cross section in FIG.

  As shown in FIG. 9, a configuration in which the guide member 40 includes a storage member 42 that is formed in communication with the guide portion 41 and stores the conveyed spring-like member M may be employed. According to this, since the spring-like member M is stored by the storage member 42 and the timing at which the spring-like member M is sent to the measuring member 50 can be adjusted, the fluctuation of the timing at which the spring-like member M is conveyed, etc. Can respond. Moreover, it can be used suitably also when employ | adopting the structure which receives the spring-shaped member M which falls mentioned above with the guide member 40. FIG. Here, the cross section in FIG. 9 corresponds to the cross section in FIG.

As shown in FIG. 10, the guide member 40 includes a plurality of guide portions 41, and an opening / closing mechanism (not shown) such as a shutter is provided below the guide portions 41 in order to control communication between each guide portion 41 and the inspection detector 23. ) Can also be adopted. Thereby, the spring-like member M can be stored by the guide part 41, can be sent to the measurement member 50 at a predetermined timing, and an efficient inspection can be performed.

  Although the shutter 63 is used as a selection member for selecting whether the spring-like member M is carried out from the non-defective product carrying-out port 61 or the defective product carrying-out port 62, the shutter 63 is not limited to this. For example, when an air nozzle is arranged near the non-defective product outlet 61 and the spring-like member M conveyed to the non-defective product outlet 61 is determined to be defective, air is ejected from the air nozzle and the spring-like member is ejected from the non-defective product outlet 61. A configuration that prevents M from being discharged can be employed.

It is also possible to arrange the defective product outlet 62 on the upstream side (selection position A7) in the rotation direction of the measurement member and arrange the non-defective product outlet 61 on the downstream side (selection position A8). In this case, the shutter 63 is controlled to open when the spring-like member M conveyed to the sorting position A7 is defective, and the shutter 63 is closed when it is non-defective.

The control device 80 does not have to be provided separately from the determination unit 36, and can be configured integrally.

[Effect of the embodiment]
According to the surface characteristic inspection / selection apparatus 1 and the surface characteristic inspection method of the present invention, an eddy current is excited in the spring-like member M by the coil 23b of the inspection detector 23, and the output signal output from the AC bridge circuit 20 is used. The surface characteristics of the spring-like member M can be evaluated. Thereby, it is possible to inspect the surface state with high accuracy with a simple circuit configuration.
Further, the spring-like member M can be reliably guided to the measurement position of the inspection detector 23 by the guide member 40. The measurement member 50 evaluates the surface characteristics of the spring-like member M by the surface characteristic inspection apparatus 2 and judges whether or not the spring-like member M is transferred from the guide member 40 to the sorting member 60. It can be used for the time for evaluating the surface characteristics of the spring-like member M and judging the quality. Thereby, it is possible to evaluate the surface characteristics of the spring-like member M and judge whether it is good or bad, corresponding to a short tact time. The sorting member 60 can reliably sort the spring-like member M into a non-defective product and a defective product.
Further, according to the surface property inspection / selection system S of the present invention, since the transport means 100 is provided, the surface property inspection / selection system capable of continuously carrying, evaluating, selecting, and unloading the spring-like member M is provided. Can be built. In addition, the non-defective product transporting unit 110 can quickly transport the non-defective product to the next process, and the defective product collecting unit 120 can select and collect only defective products, so that the sorting operation can be performed efficiently. it can.

DESCRIPTION OF SYMBOLS 1 ... Surface characteristic inspection selection device 2 ... Surface characteristic inspection device 10 ... AC power supply 20 ... AC bridge circuit 21 ... Variable resistance 22 ... Reference detector 23 ... Inspection detector 23a ... Core 23b ... Coil 30 ... Evaluation device 31 ... Amplifier 32 ... Absolute value circuit 33 ... LPF
34 ... Phase comparator 35 ... Frequency adjuster 36 ... Judgment means 37 ... Display means 38 ... Temperature measuring means 40 ... Guide member 41 ... Guide part 42 ... Storage member 50 ... Measuring member 60 ... Sorting member 61 ... Non-defective product outlet 62 ... Defective product outlet 63 ... Shutter 70 ... Rotary drive means 71 ... Rotary shaft 80 ... Control device 90 ... Outer cylinder 100 ... Conveying means 101 ... Conveying belt 102 ... Pin 103 ... Slope 110 ... Good product conveying means 120 ... Defective product collecting means S ... Surface characteristic inspection sorting system M ... Spring-like member

Claims (7)

A surface property inspection and sorting device that evaluates the surface properties of a spring-like member subjected to surface treatment and sorts non-defective and defective products,
An AC bridge circuit; an AC power supply that supplies AC power to the AC bridge circuit; and an evaluation device that evaluates surface characteristics of a spring-like member based on an output signal from the AC bridge circuit, the AC bridge circuit Can be arranged to excite eddy currents in a spring-like member with a variable resistor configured to vary the distribution ratio between the first resistor and the second resistor, and a coil capable of exciting AC magnetism And a reference detector for detecting a reference state as a reference to be compared with an output from the inspection detector, the first resistor, the second resistor, and the reference detection And the inspection detector constitute a bridge circuit, the evaluation device is supplied with AC power to the AC bridge circuit, the inspection detector detects the electromagnetic characteristics of the spring-like member, and the reference detector Standard Based on the output signal from the AC bridge circuit with the detected that the a surface characteristic inspection apparatus for evaluating the surface characteristics of the spring-like member,
A measuring member on which a plurality of the inspection detectors are arranged;
A guide member provided with a guide portion for guiding the spring-like member conveyed from the surface treatment apparatus for performing the surface treatment of the spring-like member to the measurement position of the inspection detector provided with the measurement member;
A sorting member that sorts the spring-like member after the surface characteristics are evaluated in the measuring member into a non-defective product and a defective product,
The measurement member is configured to be able to convey a spring-like member from the guide member to the sorting member, and while the measurement member conveys the spring-like member from the guide member to the sorting member, the surface characteristic inspection device A surface property inspection / selection device characterized by evaluating the surface property of a spring-like member and judging whether it is good or bad. The measurement member is configured such that a plurality of the inspection detectors are arranged concentrically, and can rotate so as to intersect with the conveying direction of the spring-like member,
In the sorting member, a non-defective product outlet for carrying out a spring-like member determined to be a non-defective product by the surface property inspection / sorting device, and a spring-like member judged to be a non-defective product by the surface property inspection / sorting device. And a non-defective product outlet, provided in a direction opposite to the rotation direction of the measurement member as seen from the guide portion of the guide member,
2. The surface characteristic inspection / selection according to claim 1, wherein the selection member includes a selection unit that selects whether the spring-like member is to be carried out from the non-defective product exit or the defective product exit. apparatus. The surface characteristic inspection / selection apparatus according to claim 1, wherein the guide member further includes a storage member that is formed in communication with the guide portion and stores the conveyed spring-like member. The surface property inspection and sorting device according to any one of claims 1 to 3,
A surface property inspection / selection system comprising: a conveying means for conveying a spring-like member subjected to surface treatment by a surface treatment device to a surface property inspection device.   A non-defective product conveying means for conveying a spring-like member selected and judged as a non-defective product, and a defective product collecting means for collecting the selected spring-like member judged as a non-defective product, are further provided. The surface property inspection and sorting system according to claim 4.   5. The surface property inspection / selection system according to claim 4, wherein the transport means includes a transport belt and a partition member that partitions a position of the transport belt on which the spring-like member is placed. A surface property inspection / selection device according to claim 1 is prepared,
A spring-like member that has been subjected to surface treatment by a surface treatment device and is conveyed is disposed at a measurement position of the inspection detector via the guide member,
The spring-shaped member is transported to the sorting member, the surface characteristics are evaluated before reaching the sorting member, and the quality is judged by the surface characteristics inspection device,
A surface characteristic inspection and selection method, wherein a spring-like member is selected into a non-defective product and a defective product on the basis of the quality determination by the surface characteristic inspection device.

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