JP2015049044A - Hole inspection method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hole inspection method in which neither a waterdrop nor a foreign matter sticks to a wide-angle lens provided at a tip of an insertion shaft.SOLUTION: When an insertion shaft 11 including a wide-angle lens 11a at a tip is inserted in a hole to inspect a hole wall surface S based on an image by the wide-angle lens 11a, first gas G1 is injected toward the bottom of the hole along a peripheral face of the insertion shaft 11, and second gas G2 is injected to the direction same as the first gas G1 in the peripheral part of the first gas G1 at a flow velocity faster than the first gas G1.

Description

  The present invention relates to a hole inspection method and apparatus.

  In recent years, using an industrial endoscope, an inner wall surface (hereinafter referred to as a hole wall surface) of a hole-shaped inspection object (hereinafter referred to as an inspection hole) is imaged, and the presence or absence of defects in the hole wall surface is inspected. To be done. At this time, an elongated insertion shaft equipped with a wide-angle lens at the tip is inserted into the inspection hole, but if an adherent such as water droplets, chips, or foreign matter adheres to the lens or the wall surface of the hole, an image taken with an endoscope Therefore, it is impossible to accurately detect the presence or absence of defects.

  Therefore, in Patent Document 1, when an insertion shaft having a wide-angle lens at the tip is inserted into a hole and the hole wall surface is inspected based on an image through the wide-angle lens, the depth of the hole along the outer peripheral surface of the insertion shaft is disclosed. It is disclosed that the gas is ejected toward

  According to this, deposits such as water droplets, chips, and foreign matters attached to the hole wall surface can be removed by the gas. In addition, fogging and water droplets on the lens surface can be removed. Therefore, inspection accuracy can be improved.

JP2013-88136A

  However, in the technique disclosed in Patent Document 1, gas is ejected along the outer peripheral surface of the insertion shaft. Therefore, the flow velocity of the gas along the outer peripheral surface of the insertion shaft is higher than the flow velocity of the gas flowing therearound. Water droplets or foreign matters that are quickly removed from the hole wall surface or float in the atmosphere are attracted to the gas having a high flow velocity. Therefore, these water droplets and foreign matters may adhere to the wide-angle lens.

  If water droplets and foreign matter adhering to the wide-angle lens increase with time, it becomes difficult to perform an accurate inspection. Therefore, it is necessary to periodically clean the wide-angle lens, and there is a problem that accurate inspection cannot be performed continuously for a long time.

  In view of the above, an object of the present invention is to provide a hole inspection method and apparatus in which water droplets or foreign matters do not adhere to a wide-angle lens provided at the tip of an insertion shaft.

  The hole inspection method of the present invention is a method for inspecting the wall surface of a hole, wherein an insertion shaft having a wide-angle lens at the tip is inserted into the hole, and the wall surface of the hole is formed based on an image through the wide-angle lens. When inspecting, the first gas is ejected toward the back of the hole along the outer peripheral surface of the insertion shaft, and at the outer peripheral portion of the first gas, the first gas is in the same direction as the first gas. The second gas is ejected at a faster flow rate.

  According to the hole inspection method of the present invention, the second gas having a faster flow rate than the first gas is ejected in the same direction as the first gas at the outer peripheral portion of the first gas. Water droplets, foreign matters, etc. floating on the surface are attracted to the second gas having a high flow velocity. Therefore, it is prevented that water droplets or foreign substances stay in the vicinity of the wide-angle lens, and these do not adhere to the wide-angle lens. This makes it possible to perform accurate inspection continuously for a long time without cleaning the wide-angle lens.

  In addition, a hole is a hole which arrange | positions a fuel injection apparatus, for example.

  A hole inspection apparatus according to the present invention is an apparatus for inspecting a wall surface of a hole, and includes a wide-angle lens at a tip, an insertion shaft to be inserted into the hole, and an inner side of the hole along the outer peripheral surface of the insertion shaft. And a gas ejection mechanism for ejecting a second gas at a flow rate faster than that of the first gas in the same direction as the first gas at the outer periphery of the first gas. And

  According to the hole inspection apparatus of the present invention, the gas ejection mechanism ejects the second gas having a flow rate faster than that of the first gas in the same direction as the first gas at the outer peripheral portion of the first gas. Alternatively, water droplets or foreign matters floating in the atmosphere are attracted to the second gas having a high flow rate. Therefore, it is prevented that water droplets or foreign substances stay in the vicinity of the wide-angle lens, and these do not adhere to the wide-angle lens. This makes it possible to perform accurate inspection continuously for a long time without cleaning the wide-angle lens.

  In addition, a hole is a hole which arrange | positions a fuel-injection apparatus, for example.

  Further, in the hole inspection apparatus according to the present invention, the gas ejection mechanism surrounds a portion on a distal end side of the insertion shaft, and extends in a longitudinal direction of the insertion shaft between an inner circumferential surface thereof and an outer circumferential surface of the insertion shaft. An inner guide forming an extending first gas ejection path, and an outer peripheral portion of the inner guide, and extending in a longitudinal direction of the inner guide between an inner peripheral surface thereof and an outer peripheral surface of the inner guide; An outer guide that forms a second gas ejection path having a smaller cross-sectional area of the ejection part than one gas ejection path, and a gas supply part that supplies gas to the first gas ejection path and the second gas ejection path It is preferable.

  In this case, the cross-sectional area of the ejection part of the second gas ejection path for ejecting the second gas is smaller than the cross-sectional area of the ejection part of the first gas ejection path. Therefore, the flow rate of the second gas is faster than the flow rate of the first gas. And a 1st gas ejection path and a 2nd gas ejection path can be simply comprised by an inner side guide and an outer side guide.

  Further, the inner guide and the distal end portion of the insertion shaft can be supported in the center of the inner space of the inner guide in a non-contact manner by the gas pressure of the first gas ejection path. Therefore, it is possible to satisfactorily support the distal end portion of the insertion shaft with the axes aligned. Furthermore, the tip portion of the hole inspection device provided with the gas ejection mechanism can be made thin and simple.

  Further, in the hole inspection apparatus of the present invention, it is provided with a support body having a gas chamber that is supplied with gas from the gas supply unit and communicates with the internal space of the inner guide, and the insertion shaft has the inner guide in the longitudinal direction thereof. It is preferable that the base end side portion is supported by the support body while being disposed so as to pass through the gas chamber.

  In this case, the insertion shaft is supported at the base end side by the support and at the distal end side by the gas pressure. Therefore, it is possible to stably support the insertion shaft with high accuracy and reduce the positional deviation of the tip portion. As a result, it is not necessary to use an expensive and large-sized high-precision bush mechanism, and it is possible to realize downsizing of the support and cost reduction of the apparatus.

The schematic sectional drawing which shows the hole inspection apparatus which concerns on embodiment of this invention. The enlarged view explaining the flow of 1st gas and 2nd gas.

  A hole inspection apparatus 10 according to an embodiment of the present invention will be described with reference to FIG. The hole inspection apparatus 10 inspects whether a defect such as a burrow exists on an inner wall surface (hereinafter referred to as a hole wall surface) S (see FIG. 2) of a hole-shaped inspection object (hereinafter referred to as an inspection hole). Used to do.

  In addition, although an inspection hole is a hole formed in order to arrange | position the fuel-injection apparatus (injector) of a direct injection engine, for example, the use, a shape, a hole diameter, a depth, etc. are not limited. For example, the inspection hole may be a through hole or a hole having a bottom wall. Further, the inspection hole may be a straight hole having a constant hole diameter or a tapered hole in which the hole diameter gradually changes.

  The hole inspection device 10 includes an insertion shaft 11, a support bracket (support) 12, an inner guide 13, an outer guide 14, and a gas supply means 15.

  The insertion shaft 11 is an elongated rod-like body as an overall appearance, and a distal end portion (lower end portion) in the longitudinal direction (vertical direction in FIG. 1; hereinafter also referred to as vertical direction) is inserted into the inspection hole at the time of inspection. The insertion shaft 11 is provided with a wide-angle lens 11a such as a fisheye lens at its most distal end.

  Here, the insertion shaft 11 is configured as an endoscope. Specifically, the insertion shaft 11 has a cylindrical outer shell made of a hard material such as stainless steel. Although not shown, the insertion shaft 11 incorporates a lens mechanism including a wide-angle lens 11a, an image pickup device such as a CCD or a CMOS, and the like at the distal end.

  However, the insertion shaft 11 is not limited to a built-in image sensor. For example, the image of the hole wall surface S through the wide-angle lens 11a is formed on the imaging surface of the imaging device disposed outside the hole inspection device 10 through a lens mechanism or an optical fiber built in the insertion shaft 11. There may be.

  The image signal of the hole wall surface image photoelectrically converted by the image sensor is transmitted to an image signal processing unit (not shown) existing in the insertion shaft 11 or outside the hole inspection device 10 via a signal line, and a video signal is generated. . Then, the generated video signal is output to the image display device 20 outside the device 10, and an image of the hole wall surface S is displayed on the display screen of the image display device 20.

  The presence or absence of a defect is inspected by an inspector who views this image. Alternatively, although not shown, the generated video signal is transmitted to the video analysis device, and the presence / absence of a defect is automatically determined.

  The support bracket 12 includes a bracket body 16 and two support bushes 17 and 18. The bracket body 16 is made of a hard material such as stainless steel, and the first support portion 16a and the second support portion 16b are connected by a connecting portion 16c and formed integrally.

  The first support portion 16a is located on the distal end side (lower side), and a gas chamber 16d composed of a cylindrical space is formed therein. The upper and lower sides of the gas chamber 16d are open. And the gas supply port 16e for supplying gas to the gas chamber 16d is formed in the side wall of the 1st support part 16a. The gas is preferably an inert gas such as nitrogen or air, but is not particularly limited.

  The first support bush 17 is fixedly attached to the first support portion 16a by a fastening screw (not shown) on the base end side (upper side) of the first support portion 16a, and seals the upper side of the gas chamber 16d. The first support bush 17 has a through hole formed in the center thereof, and the insertion shaft 11 is inserted in an airtight manner into the through hole. Thereby, the intermediate portion of the insertion shaft 11 is fixedly supported by the first support bush 17.

  The 2nd support part 16b is located in the base end side, and the through-hole by which the 2nd support bush 18 is mounted | worn is formed. The second support bush 18 has a through hole formed at the center thereof, and the insertion shaft 11 is inserted through the through hole. Accordingly, the proximal end portion of the insertion shaft 11 is fixedly supported by the second support bush 18.

  The inner guide 13 surrounds a portion on the distal end side of the insertion shaft 11 and guides the ejection of the first gas G1. The inner guide 13 is made of, for example, a known resin material.

  A cylindrical through-hole penetrating in the longitudinal direction (vertical direction) of the insertion shaft 11 is formed in the center portion of the inner guide 13, and a portion on the distal end side of the insertion shaft 11 is inserted into the through-hole. . However, the most distal portion of the insertion shaft 11 protrudes from the inner guide 13. Note that the inner peripheral surface of the inner guide 13 and the outer peripheral surface of the insertion shaft 11 are not in contact with each other at normal times, and a gap is formed between them. The cylindrical gap extending in the vertical direction is a first gas ejection path R1 through which the first gas G1 is ejected.

  The inner guide 13 has a cylindrical guide body 13a having an inner peripheral surface larger than the outer diameter of the insertion shaft 11, an annular plate-shaped flange 13b formed at the upper end of the guide body 13a, A cylindrical insertion portion 13c having an outer diameter substantially the same as the diameter of the through hole formed below the gas chamber 16d of the first support portion 16a is integrally formed. The inner guide 13 is fixedly attached to the bracket body 16 with a fastening screw (not shown).

  In the guide main body 13a, a plurality of, for example, four through holes 13d penetrating in the horizontal direction are formed uniformly in the circumferential direction.

  The inner guide 13 is inserted into the lower portion of the gas chamber 16d whose opening 13c is opened at the lower side, and the upper surface of the flange 13b and the lower surface of the bracket main body 16 come into contact with each other. It is mounted on the underside.

  The outer guide 14 surrounds the guide main body 13a of the inner guide 13, and guides the ejection of the second gas G2. The outer guide 14 is made of, for example, a known resin material. The outer guide 14 is fixedly attached to the bracket body 16 with a fastening screw (not shown).

  A cylindrical through-hole penetrating in the longitudinal direction (vertical direction) of the insertion shaft 11 is formed at the center of the outer guide 14, and the guide main body 13 a of the inner guide 13 is disposed at the center of the through-hole. The A gap is formed between the inner peripheral surface of the outer guide 14 and the outer peripheral surface of the guide main body 13 a of the inner guide 13. The cylindrical gap extending in the vertical direction is a second gas ejection path R2 through which the second gas G2 is ejected. The cross-sectional area of the ejection part of the second gas ejection path R2 is smaller than the cross-sectional area of the ejection part of the first gas ejection path R1.

  The gas supply means 15 includes a hose 15a, a connector (connector) 15b for connecting the hose 15a to the gas supply port 16e, and a gas supply unit 15c including a compressor (compressor), a gas cylinder, a control valve, and the like. ing. The compressor or the like of the gas supply unit 15c is connected to the control device 30 outside the hole inspection device 10, operates according to a control signal from the control device 30, and supplies high-pressure gas into the gas chamber 16d.

  In the hole inspection apparatus 10 configured as described above, the high-pressure gas supplied from the gas supply means 15 into the gas chamber 16d is inspected along the outer peripheral surface of the insertion shaft 11 via the first gas ejection path R1. It ejects as the 1st gas G1 toward the back (downward) of a hole. Furthermore, a part of the high-pressure gas passes through the through hole 13d of the inner guide 13, and toward the back (downward) of the inspection hole at the outer periphery of the first gas G1 via the second gas ejection path R2. It ejects as the second gas G2. Thus, the gas ejection mechanism 19 in the hole inspection apparatus 10 includes the first gas ejection path R1, the second gas ejection path R2, the gas chamber 16d, and the gas supply means 15.

  Hereinafter, a hole inspection method using the hole inspection apparatus 10 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  First, the inside of the inspection hole formed by cutting or the like is cleaned with water or the like before the inspection. Then, the operator inserts the distal end portion of the insertion shaft 11 of the hole inspection device 10 automatically or manually into the inspection hole.

  At this time, high-pressure gas is supplied from the gas supply means 15. When the high pressure gas is supplied to the gas chamber 16d by the gas supply means 15, the gas chamber 16d is filled with the high pressure gas.

  Furthermore, the high-pressure gas filled in the gas chamber 16d passes through the first gas ejection path R1 from the tip of the inner guide 13 toward the back of the inspection hole along the outer periphery of the insertion shaft 11, and becomes the first gas G1. Erupts. Further, a part of the high-pressure gas is ejected as the second gas G2 toward the back of the inspection hole on the outer periphery of the first gas via the second gas ejection path R2. Further, due to the ejection of the second gas G2, a gas flow having a flow velocity slower than the flow velocity of the second gas G2 is generated on the outer periphery of the second gas G2.

  And the hole wall surface S is imaged, moving the insertion shaft 11 to the back of an inspection hole gradually as needed. After performing appropriate image processing such as development processing on the captured image, an inspector visually confirms the image displayed on the image display device 20 or automatically by a video analysis device (not shown). Inspect for any defects.

  By the way, on the hole wall surface S after processing and cleaning, there are cases in which deposits such as water droplets used for cleaning, chips and foreign matters not removed by cleaning are attached. When an adhering substance adheres to the hole wall surface S, there is a possibility that overdetection may occur, and the inspection accuracy is lowered. Further, the inside of the inspection hole immediately after the cleaning is high temperature and high humidity, and there is a possibility that the surface of the wide-angle lens 11a is fogged. When fogging exists on the lens surface, it becomes difficult to capture an accurate image, and the inspection accuracy decreases.

  However, in the hole inspection method using the hole inspection device 10, the second gas G <b> 2 is ejected from the second gas ejection path R <b> 2 while inserting the distal end portion of the insertion shaft 11 into the inspection hole, and the distal end portion of the insertion shaft 11. The second gas G2 in a laminar flow is caused to flow toward the back of the inspection hole along the entire outer peripheral surface of the. As a result, a negative pressure is generated as shown by the white arrow in FIG. 2, and adhering substances such as water droplets, chips and foreign matters adhering to the hole wall surface S are sucked to the insertion shaft 11 side and reliably removed. Can do. Therefore, inspection accuracy can be improved.

  Furthermore, the effect of removing the deposit on the hole wall surface S can be made equal to or greater than the method of removing the deposit by air blowing from outside the inspection hole. Therefore, it is possible to abolish the work of air blowing in the inspection hole before the inspection.

  Further, since the first gas G1 is ejected from the first gas ejection path R1, an air current vortex is generated in the vicinity of the surface of the wide-angle lens 11a as indicated by an arrow in FIG. As a result, as shown by the white arrow in FIG. 2, a negative pressure that peels off the adhered matter on the lens surface is generated, so that water droplets and cloudiness on the lens surface can be reliably removed. Therefore, even in an environment of high temperature and high humidity, the wide-angle lens 11a can take an image with a clear state, and the inspection accuracy can be improved.

  And since the 2nd gas G2 of the flow velocity faster than the 1st gas G1 is spouted in the outer peripheral part of the 1st gas G1 in the same direction as the 1st gas G1, it was removed from the hole wall surface S or floated in atmosphere Water droplets and foreign matters are attracted to the second gas G2 having a high flow rate. Therefore, the second gas G2 prevents water droplets and foreign matter from staying in the vicinity of the wide-angle lens 11a, and these do not adhere to the wide-angle lens 11a. Thereby, it becomes possible to perform an accurate inspection continuously for a long time without cleaning the wide-angle lens 11a.

  Furthermore, even when the inside of the inspection hole is cleaned with water or the like, it is not necessary to wait until it is dried, and inspection (imaging) can be performed immediately after cleaning. Therefore, it is possible to shorten the time required to complete the inspection.

  Further, the adhering matter adhering to the hole wall surface S and the lens surface can be removed at the same time or substantially simultaneously with the imaging. Therefore, there is very little possibility that foreign matter or the like will flow into the inspection hole after cleaning until imaging, and deposits adhere to the hole wall surface S or the lens surface.

  Furthermore, a high gas pressure acts equally on the first gas ejection path R1 over the entire outer circumference of the insertion shaft 11 by Pascal's principle. Therefore, the distal end portion of the insertion shaft 11 can be supported in the center of the inner space of the inner guide 13 in a non-contact manner by the gas pressure, and the insertion shaft 11 can be favorably supported with the axes aligned. Become.

  And the intermediate part and proximal end side of the insertion shaft 11 are each supported by the two support bushes 17 and 18, and the front end side of the insertion shaft 11 is supported by the gas pressure. Thereby, the axial misalignment of the insertion shaft 11 is prevented, and even if the axial misalignment occurs, it is automatically corrected and the backlash can be reduced.

  This effect is high if the vertical machining accuracy of the inner wall surface of the gas chamber 16d and the inner wall surface of the inner guide 13 is good. Therefore, it is not necessary to use an expensive and large-sized high-precision bush mechanism by sufficiently securing these processing accuracy. Therefore, it is possible to achieve downsizing of the support bracket 12, reduction in positional deviation of the distal end portion of the insertion shaft 11, and cost reduction.

  For example, when the distal end side of the insertion shaft 11 is supported by a bush mechanism as in the prior art, the portion having the bush mechanism is enlarged and cannot be inserted if the inspection hole is thin. For this reason, in particular, when the wall surface S of the narrow hole is inspected to the deep part, there is not a little misalignment at the tip of the insertion shaft 11. On the other hand, in the hole inspection device 10, if the outer guide 14 is a narrow hole that can be inserted into the inspection hole, the positional deviation in the vicinity of the distal end portion of the insertion shaft 11 can be greatly reduced.

  Furthermore, by setting the inner guide 13 and the outer guide 14 to be long so that the lengths of the first gas ejection path R1 and the second gas ejection path R2 are increased, the first gas can be generated with low loss without generating turbulence. G1 and the second gas G2 can be ejected. As a result, it is possible to effectively prevent fogging and remove deposits.

  If the lengths of the inner guide 13 and the outer guide 14 are set so that the protruding amount of the insertion shaft 11 is shortened, the contact between the insertion shaft 11 and the hole wall surface S can be more reliably prevented. However, in this case, the outer diameter near the tip of the hole inspection device 10 is increased, and the possibility that the outer guide 14 contacts the hole wall surface S is increased. Therefore, it is preferable to appropriately set the protruding amount of the insertion shaft 11 according to the taper angle of the inspection hole.

  As described above, in the hole inspection method using the hole inspection device 10, three effects of removing the deposits on the hole wall surface S and the lens surface, preventing the anti-fogging of the lens, and stably supporting the insertion shaft 11 can be realized. . Therefore, the inspection accuracy of the hole wall surface S is improved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, the support bracket 12 does not have the second support portion 16 b, and the proximal end side of the insertion shaft 11 may not be supported by the support bush 18. Moreover, although the case where the cross section of the insertion shaft 11, the inner side guide 13, the outer side guide 14, and the gas chamber 16d was circular was demonstrated, these cross sections are not limited to circular, Arbitrary shapes, such as a polygon, may be sufficient. .

  DESCRIPTION OF SYMBOLS 10 ... Hole test | inspection apparatus, 11 ... Insertion shaft, 11a ... Wide angle lens, 12 ... Support bracket (support body), 13 ... Inner guide, 13a ... Guide main body, 13b ... Gutter part, 13c ... Insertion part, 13d ... Through-hole, DESCRIPTION OF SYMBOLS 14 ... Outer guide, 15 ... Supply means, 15a ... Hose, 15b ... Connector, 15c ... Gas supply part, 16 ... Bracket main body, 16a ... First support part, 16b ... Second support part, 16c ... Connection part, 16d ... Gas chamber, 16e ... Gas supply port, 17 ... First support bush, 18 ... Second support bush, 19 ... Gas ejection mechanism, 20 ... Image display device, 30 ... Control device, 51 ... Turbine blade, 54 ... Rotary encoder, G1 ... 1st gas, G2 ... 2nd gas, R1 ... 1st gas ejection path, R2 ... 2nd gas ejection path, S ... Hole wall surface.

Claims (4)

A method for inspecting the wall of a hole,
When inserting the insertion shaft having a wide-angle lens at the tip into the hole and inspecting the wall surface of the hole based on the image through the wide-angle lens,
And spouting the first gas along the outer peripheral surface of the insertion shaft toward the back of the hole,
A hole inspection method in which a second gas is ejected at a flow rate faster than the first gas in the same direction as the first gas at the outer periphery of the first gas. A device for inspecting the wall of a hole,
A wide-angle lens at the tip, an insertion shaft inserted into the hole;
The first gas is ejected along the outer peripheral surface of the insertion shaft toward the back of the hole, and at the outer peripheral portion of the first gas, the flow velocity is faster than the first gas in the same direction as the first gas. And a gas jetting mechanism for jetting the second gas. The gas ejection mechanism is
An inner guide surrounding a portion on the distal end side of the insertion shaft and forming a first gas ejection path extending in the longitudinal direction of the insertion shaft between an inner peripheral surface thereof and an outer peripheral surface of the insertion shaft;
Surrounding the outer peripheral portion of the inner guide, extending in the longitudinal direction of the inner guide between the inner peripheral surface and the outer peripheral surface of the inner guide, and having a smaller cross-sectional area of the ejection portion than the first gas ejection path An outer guide forming a two-gas ejection path;
The hole inspection apparatus according to claim 2, comprising a gas supply unit that supplies gas to the first gas ejection path and the second gas ejection path. Gas is supplied from the gas supply unit, comprising a support having a gas chamber communicating with the internal space of the inner guide,
The said insertion shaft is arrange | positioned so that the said inner side guide and the said gas chamber may be penetrated in the longitudinal direction, The part by the side of a proximal end is supported by the said support body. Hole inspection equipment.