Surface property inspection apparatus, surface property inspection system, and surface property inspection method

Patent metadata

Field	Value
Publication number	US-9638668-B2
Application number	US-201514707600-A
Country	US
Kind code	B2
Filing date	May 8, 2015
Priority date	May 30, 2013
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

To provide a surface property inspection apparatus, surface property inspection system, and surface property inspection method capable of inspecting the surface processing state of processed material subjected to surface processing such as shot-peening, heat treatment, or nitriding with high accuracy and low vulnerability to temperature changes in the inspection environment. Surface property inspection apparatus is furnished with a AC power supply, a AC bridge circuit, and an evaluation device; AC bridge circuit comprises variable resistor with which distribution ratio γ is variable, reference detector, and inspection detector. Inspection detector is furnished with a coil wound so as to oppose the surface property inspection region of object under inspection M, and by supplying AC power from AC power supply to coil, an eddy current is excited in object under inspection M. Thus the magnetic properties of object under inspection M can be detected, and inspection of surface properties based on the output signal from AC power supply is possible.

First claim

What is claimed is:

1. A surface property inspection apparatus for inspecting surface properties of an object under inspection subjected to surface processing, comprising:
an AC bridge circuit;
an AC power supply for supplying AC power to the AC bridge circuit; and
an evaluation apparatus for evaluating the surface properties of the object under inspection based on an output signal from the AC bridge circuit;
wherein the AC bridge circuit has a variable resistor configured so that the distribution ratio is variable between a first resistor and a second resistor, an inspection detector furnished with a coil for creating an AC magnetic field and exciting an eddy current in the object under inspection, and a reference detector for inspecting a reference state serving as reference for comparing with the output from the inspection detector; and whereby the first resistor, the second resistor, the reference detector, and the inspection detector constitute the AC bridge circuit; and
wherein the evaluation apparatus evaluates the surface properties of the object under inspection based on an output signal from the AC bridge circuit, in a state whereby AC power is supplied to the AC bridge circuit, the inspection detector detects an electromagnetic properties of the object under inspection and the reference detector detects a reference state, and
wherein the coil is wound to surround a surface property inspection region of the object under inspection, and an eddy current is excited in the surface property inspection region by supplying AC power to the coil.

2. The surface property inspection apparatus of claim 1 , wherein the surface property inspection apparatus is built into a surface treatment apparatus for performing shot-peening as the surface processing; and
the surface property inspection apparatus is furnished with a moving mechanism for positioning the object under inspection at an evaluation position, being the inside of the coil of the inspection detector, by conveying and moving the object under inspection or the inspection detector.

3. The surface property inspection apparatus of claim 1 , further comprising a first transport mechanism, whereby the object under inspection is drivable up or down, and the object under inspection is transported to an evaluation position inside the inspection detector coil and to a position either above or below said evaluation position, or both; and
a registration portion for registering the object under inspection at a position within a horizontal plane;
whereby surface properties of the object under inspection are evaluated either in-line or out-line in a surface processing step by a shot-peening apparatus for performing shot-peening as surface processing.

4. The surface property inspection apparatus of claim 2 , wherein the inspection detector is configured to excite an eddy current in an object under inspection furnished with a gear portion.

5. The surface property inspection apparatus of claim 4 , further comprising a magnetic shield disposed on the outside of the coil so as to surround the object under inspection, blocking off external magnetism.

6. The surface property inspection apparatus of claim 5 , further comprising a temperature sensor for measuring the temperature of the surface of the object under inspection; and
wherein the evaluation apparatus makes a pass/fail judgment of the surface processing state of the object under inspection if the temperature detected by the temperature sensor is within a predetermined range, and does not make a pass/fail judgment of the surface processing state of the object under inspection if the temperature detected by the temperature sensor is outside the predetermined range.

7. A surface processing apparatus, comprising the surface property inspection apparatus of claim 2 , and a holding portion for holding the object under inspection in a registered state, the surface processing apparatus performing shot-peening as the surface processing,
wherein the object under inspection held by the holding portion is positioned at an evaluation position inside the coil of the inspection detector by transporting and moving the object under inspection held by the holding portion or the inspection detector, and the surface property inspection apparatus inspects the surface properties of the object under inspection before and after shot-peening or after shot-peening.

8. A surface processing system, comprising:
the surface property inspection apparatus of claim 3 ;
a surface processing apparatus for performing shot-peening as the surface processing;
a second transport mechanism for transporting the object under inspection moved to a first standby position by the first transport mechanism in a horizontal direction or a direction inclined relative to the horizontal direction and for transporting the object under inspection up to a predetermined position on the surface processing apparatus; and
a third transport mechanism capable of transporting the object under inspection in a horizontal direction or a direction inclined relative to the horizontal direction, and of transporting the object under inspection from a pre-shot-peening area via a second standby position to a shot-peening and inspection-completed area;
whereby the first standby position is a position above or below the evaluation position and facing the surface processing position;
the second standby position is the evaluation position or a position above or below the evaluation position;
the third transport mechanism transports the object under inspection from the pre-shot-peening area up to the second standby position; and
by movement of at least one of either the object under inspection or the inspection detector, transported to the second standby position, the object under inspection is positioned in the evaluation position of the inspection detector; and
the third transport mechanism transports an object under inspection moved to the second standby position by the first transport mechanism to the shot-peening and inspection-completed area.

9. The surface processing system of claim 8 , further comprising an inspection detector transport mechanism for moving the inspection detector up and down;
whereby the second standby position is the evaluation position; and
when the object under inspection is transported as far as the second standby position, the object under inspection is positioned at the evaluation position of the inspection detector by the movement of the inspection detector up or down by the inspection detector transport mechanism.

10. The surface processing system of claim 8 , wherein the second standby position is a position either above or below the evaluation position; and
an object under inspection transported as far as the second standby position is positioned at the evaluation position of the inspection detector by being moved up or down by the first transport mechanism.

11. A surface property inspection method, comprising steps of:
a providing step for providing the surface property inspection apparatus of claim 1 ;
a disposition step for disposing the inspection detector so that an eddy current is excited in the object under inspection by supplying AC power from the AC power supply to the AC bridge circuit; and
an evaluation step for evaluating the surface properties of the object under inspection based on the output signal output from the AC bridge circuit.

12. The surface property inspection method of claim 11 , further comprising a step for preparing and measuring a reference inspection piece in order to output a reference output for detecting a reference state in the reference detector.

Assignees

• Sintokogio Ltd

Inventors

• Makino Yoshiyasu
• Kaga Hideaki

Classifications

• G01N27/9046 Primary

  by analysing electrical signals · CPC title

• C21D11/00

  Process control or regulation for heat treatments · CPC title

• C21D7/06

  by shot-peening or the like · CPC title

• G01N27/9006

  Details, e.g. in the structure or functioning of sensors · CPC title