JP6071227B2 - Internal imaging device - Google Patents

Description

  The present invention relates to an inner surface photographing apparatus, and relates to a technique for photographing an inner surface of a hole of an object, an inner surface of a pipe, and the like in an environment where high temperature, high humidity, and dust are used.

  Conventionally, this type of photographing apparatus has a principle shown in FIG. 9, for example. This is called a ring beam device, and the conical mirror 3 is irradiated with a circular laser beam 2 from the semiconductor laser of the laser irradiation unit 1, and the laser beam 2 incident on the conical mirror 3 is incident on the incident optical axis. Thus, a disk-like light 4 is formed which is reflected in a right angle direction and has a light trace extending 360 °. The laser irradiation unit 1 and the conical mirror 3 are integrated by a transparent cylindrical body 5.

  When the disk-shaped light 4 is irradiated onto the inner surface of the object, the inner surface of the object is illuminated in a ring shape, and the ring-shaped light cutting surface is illuminated. As shown in FIG. 11, the ring of light reflected as the light cut surface is a single ring-shaped light 6 representing the cross-sectional contour of the inner surface of the object. In the following, the light section is used as a term indicating the cross-sectional contour of the inner surface of the object.

By capturing this ring-shaped light 6 with a camera (not shown) of an imaging unit located behind the laser irradiation unit 1, contour shape information on the inner surface of the object can be obtained.
In the optical device described in Patent Document 1, the measurement light from the light source is reflected by the reflection part of the cone mirror through the lens system, and is measured as wide, radial defect measurement light through the opening of the light shielding member. Output to the target side. The measurement light that has passed through the through hole of the cone mirror is reflected by the reflection portion around the top of the cone mirror, and is passed through the opening of the light shielding member to the measurement target side as narrow and radial length characteristic measurement light. Is output. The defect measurement light and the length characteristic measurement light reflected by the measurement object are each detected by the measurement unit, and the operation control unit determines the presence / absence of the defect to be measured, calculates the shape, and the like.

JP2009-25006

  By the way, in the configuration shown in FIG. 9 described above, it is necessary to insert the laser irradiation unit 1 and the imaging unit located behind it into an object such as a tube as an integral unit. And a connecting member for connecting the two.

  Since this connecting member is located within the imaging field of view of the camera of the photographing unit, it is required that the imaging field of view is not obstructed. For this reason, an intermediate glass cylinder 7 made of transparent glass is disposed between the laser irradiation unit 1 and the imaging unit, and the imaging unit keeps the laser irradiation unit 1 horizontal and centered via the intermediate glass cylinder 7. And keep it within the distance of focus.

However, in an environment where there is a lot of dust, dust adheres to the outer surface of the transparent cylinder 5 covering the conical mirror 3 and the outer surface of the intermediate glass cylinder 7 between the laser irradiation unit 1 and the imaging unit.
The dust adhering to the transparent cylindrical body 5 of the conical mirror 3 hinders the irradiation of the laser beam so that the laser beam does not reach the inner surface of the object. A part of the ring-shaped light 6 becomes invisible, and as shown in FIG. 10, an image of the ring-shaped light 6 is lost.

  Moreover, since the intermediate glass cylinder 7 accommodates the laser irradiation part 1, the outer diameter becomes large, and when the inner diameter of the inner surface of the object is small, the intermediate glass cylinder 7 contacts the inner surface of the object and is damaged. There is a fear. When the distance from the conical mirror 3 to the photographing part, that is, the working distance is long, the intermediate glass cylinder 7 alone is insufficient in strength, so that a reinforcing member is required. It cannot be secured.

  Further, although the wiring to the laser irradiation unit 1 is routed along the inner surface of the intermediate glass cylindrical body 7, a very thin electric wire is used so as not to obstruct the imaging field of view, and structural factors that are easily broken have.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object thereof is to provide an inner surface photographing apparatus that can reliably perform photographing even in a dusty usage environment.

In order to solve the above-described problem, an inner surface photographing apparatus of the present invention photographs an inner surface of an object facing the inner space of the object along a direction in which the object moves into and out of the inner space. A light source unit that emits light from the light source unit toward the inner surface of the object as a radial irradiation light, and a light cut surface of the inner surface of the object illuminated by the irradiation light. An imaging unit having an imaging device that continuously shoots along the retraction direction, and a connection unit that connects the irradiation unit and the imaging unit, the imaging unit is located in the central region of the imaging field of the imaging device, A transparent protective material arranged in the imaging field of view of the imaging unit covers the front of the imaging device in a direction crossing the connection unit, and the connection unit has a hollow part that communicates the irradiation unit and the imaging unit and penetrates the transparent protection material. fixed Te, that wiring to the irradiation portion is inserted into the hollow portion of the connecting portion And butterflies.

In the inner surface photographing apparatus of the present invention , the connecting portion is made of a resin or metal pipe body.

  In the inner surface photographing apparatus of the present invention, the transparent protective material is made of plate glass.

  As described above, according to the present invention, the connecting portion is located in the central region of the imaging field of the imaging device, and the transparent protective material, for example, plate-like glass disposed in the imaging field of the imaging unit crosses the connecting portion. By covering the front of the photographic device, the outer surface of the transparent protective material will be in the vertical direction, the outer surface of the transparent protective material will be difficult for dust to settle, and the dust that has reached the outer surface of the transparent protective material will also be Since it slides down, it can suppress that dust adheres to the outer surface of a transparent protective material.

  Since the connecting part is located in the central region of the imaging field of view of the imaging device that does not affect the imaging of the inner surface of the object, the imaging field of view is not obstructed even if a thick wiring is provided in the hollow part of the connecting part, and disconnection etc. The structural factor that causes the failure can be eliminated.

  In addition, since the strength of the connecting part can be ensured by adopting a resin or metal pipe body for the connecting part, even if the working distance is long, the photographing part can be inserted through the pipe body without the need for a reinforcing member. Thus, the irradiation unit can be held horizontally and within a distance in focus while maintaining the center position, and a 360 ° field of view can be secured.

The side view which shows the inner surface imaging device in embodiment of this invention The perspective view which shows the principal part of the same inner surface imaging device The top view which shows the whole inner surface imaging device Side view showing the entire internal imaging device The principal part enlarged view which shows other embodiment of this invention The principal part enlarged view which shows other embodiment of this invention Overall configuration diagram showing another embodiment of the present invention Schematic diagram showing differences in working distance Schematic diagram showing the conventional configuration Schematic diagram showing abnormal ring light Schematic diagram showing normal ring light

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIGS. 1 to 4, the inner surface photographing apparatus exits and retreats with respect to an object, for example, a hollow hole that is an inner space of the tube, and exits the inner surface of the object, for example, the inner surface of the tube. An image is taken along the retraction direction, and includes an irradiation unit 10, an imaging unit 20, and a connecting unit 50 as main components.

  The irradiating unit 10 irradiates the light source light toward the inner surface of the object as a radial irradiation light, and includes a light source unit 16 inside the support holder 11, and a semiconductor laser stored in the light source unit 16. Emits laser light as light source light.

  A protective case 12 made of a transparent glass cylinder attached in front of the light source unit 16 is positioned on the front end side of the support holder 11, and a lid 13 is connected to the rear end side of the support holder 11 with a bolt 14. The protective case 12 houses a conical mirror 15 therein.

  The light source unit 16 is inserted into the hole 111 of the support holder 11 and is fixed to the support holder 11 with a bolt 112. The support holder 11 integrally holds the protective case 12 via the light source unit 16, and the end surface of the support holder 11 has an opening 113 of the hole 111 around the protective case 12. A hollow portion 114 and a communication hole 115 that communicates the hole portion 111 and the hollow portion 114 are formed between the lid portion 13 and the hole portion 111 of the support holder 11.

The conical mirror 15 reflects the laser beam emitted from the semiconductor laser in a direction perpendicular to the incident optical axis, and forms a disk-shaped irradiation light in which the light trace spreads radially at 360 °.
The photographing unit 20 continuously photographs the light cut surface of the inner surface of the object illuminated by the irradiation light along the exit / retreat direction. From the connection unit 21, the lens unit 22 that forms the photographing device, and the camera unit 23. Become. The connecting portion 21 is screwed to the hood 24 of the lens portion 22 on the rear end side, and has a flange 25 on the front end side.

  The flange 25 is connected to a transparent protective material 26 arranged in the imaging field of view of the imaging unit 20 by bolts and nuts 27, and is connected to the central region of the transparent protective material 26, that is, the central region of the imaging field of the imaging device. 50 is located, and the transparent protective material 26 covers the front of the lens portion 22 in a direction crossing the connecting portion 50. The transparent protective material 26 is made of glass, and in the present embodiment, is made of plate glass, and the surface of the plate glass forms a flat surface along the vertical direction. However, the transparent protective material 26 may have a shape that forms an inclined surface with a downward slope downward, may have a conical shape that protrudes toward the irradiation unit 10, or may have a hemispherical shape, Any shape may be used as long as dust or the like slides down on the surface.

  A relay wiring for relaying the laser power cable 28 is inserted into the connecting portion 50, and a wiring connector 29 for the relay wiring and a first air blow for supplying compressed air are connected to the connecting portion 21. A port 30 is provided, and the first air supply tube 31 is connected to the first air blowing port 30.

  The lens unit 22 includes a hood 24 and a camera lens 32 connected to the hood 24. The camera unit 23 includes a camera 33 as a photographing device connected to the camera lens 32 and a casing 34 that stores the camera 33. The casing 34 is provided with a second air blowing port 35 for supplying compressed air, and a second air supply tube 36 is connected to the second air blowing port 35.

  The connecting part 50 connects the irradiation part 10 and the photographing part 20, has a hollow part 51 communicating with the support holder 11 and the connection part 21, is made of a resin or metal pipe body, and supports the irradiation part 10. It has sufficient strength necessary for this. One end of the connecting portion 50 passes through the lid 13 of the irradiation unit 10 and is fixed to the lid 13, and the other end passes through the transparent protective member 26 of the photographing unit 20 and is fixed to the transparent protective member 26. The laser power cable 28 is inserted into the hollow portion 51 of the connecting portion 50.

  The inner surface photographing device is provided at the distal end of the insertion rod 60, the casing 34 of the photographing unit 20 is fixed to a pedestal portion 61 provided at the distal end of the insertion rod 60, and the laser power cable 28 and the first air supply are provided. The tube 31 and the second air supply tube 36 are inserted into the insertion rod 60.

  The operation of the above configuration will be described below. The insertion rod 60 is inserted into the tube of the object, the inner surface photographing device is arranged in the tube, and the inner surface of the object is photographed by the inner surface photographing device while the insertion rod 60 is inserted into or extracted from the tube. At this time, electric power is supplied to the semiconductor laser of the light source unit stored in the support holder 11 of the irradiation unit 10 through the laser power cable 28 inserted into the insertion rod 60. Since the connecting part 50 is located in the center region of the imaging field that does not affect the imaging of the inner surface of the object, the imaging field can be reduced even if a thick wiring is used for the laser power cable 28 arranged in the hollow part 51 of the connecting part 50. It is no longer obstructed, and structural factors that cause failures such as disconnection can be eliminated.

  The plate-like glass of the transparent protective material 26 covers the front of the lens portion 22 in a direction crossing the connecting portion 50, and the surface of the plate-like glass forms a flat surface along the vertical direction. The surface is difficult for dust to accrete, and the dust that reaches the outer surface of the transparent protective material also slides down, so that it is possible to suppress the dust from adhering to the outer surface of the transparent protective material, and the captured image interferes with the field of view. Can be prevented.

  In the irradiation unit 10, the semiconductor laser of the light source unit stored inside the support holder 11 emits laser light toward the conical mirror 15 as light source light. The conical mirror 15 reflects the laser beam emitted from the semiconductor laser in a direction perpendicular to the incident optical axis, and forms a disc-shaped irradiation light in which the light trace radiates at 360 ° toward the inner surface of the tube as the inner surface of the object. Irradiate. When this disc-shaped light is irradiated onto the inner surface of the object, the inner surface of the object is illuminated in a ring shape, and the ring-shaped light cutting surface is illuminated. The ring of light reflected on the light cut surface becomes one ring-shaped light that represents the cross-sectional contour of the inner surface of the object. By capturing this ring-shaped light with the camera 33 of the imaging unit 20, the contour shape information of the inner surface of the object is obtained.

At the time of shooting, the connecting unit 50 is located in the center region of the imaging field of view of the camera 33, so that it does not hinder the shooting of the inner surface of the object.
Even if the working distance is long, the reinforcing member can be used by adopting a pipe body having a strength sufficient to support the irradiation unit 10 for the connection unit 50 that connects the irradiation unit 10 and the photographing unit 20. Without being necessary, the imaging unit 20 can secure a 360 ° field of view by holding the irradiation unit 10 horizontally through the pipe body and keeping the center position within a focused distance. Further, as shown in FIG. 8A, when the working distance is short, it is necessary to adopt the camera lens 32 and the camera 33 having a wide imaging field of view in the photographing unit 20, but as shown in FIG. 8B. In addition, when the working distance is long, it is necessary to employ the camera lens 32 and the camera 33 with a narrow imaging field of view in the photographing unit 20.

  Further, compressed air is supplied from the first air blowing port 30 to the connection portion 21 through the first air supply tube 31, and compressed air is supplied from the second air blowing port 35 to the casing 34 through the second air supply tube 36.

  The compressed air supplied to the connecting portion 21 is supplied to the support holder 11 using the hollow portion 51 of the connecting portion 50, and the compressed air is ejected from the opening portion 113 of the hole portion 111 onto the outer surface of the protective case 12. Thus, by air purging the outer surface of the protective case 12, dust can be prevented from adhering to the outer surface of the protective case 12, and inhibition of laser light irradiation can be suppressed.

  The compressed air supplied to the casing 34 is exhausted from a gap between the walls of the casing 34, and air can flow inside the casing 34. For this reason, the inside of the casing 34 can be cooled and dehumidified, and the operation of the camera 33 can be guaranteed regardless of the use environment.

This compressed air is preferably dried, and is preferably temperature-controlled.
For this reason, as shown in FIG. 7, an air supply device 70 is connected to the first air supply tube 31 and the second air supply tube 36. The air supply device 70 includes a compressor 71, a temperature adjustment mechanism (air conditioner) 72, an air dryer 73, and a regulator 74 that are sequentially arranged from the upstream side to the downstream side.

  The air compressed by the compressor 71 is temperature-adjusted by a temperature adjusting mechanism (air conditioner) 72, passes through an air dryer 73, and is supplied while adjusting the pressure by a regulator 74.

  Compressed air subjected to temperature control and drying is supplied from the first air blowing port 30 to the connection portion 21 through the first air supply tube 31, and the temperature is supplied from the second air blowing port 35 to the casing 34 through the second air supply tube 36. Supply controlled and dried compressed air.

  By supplying compressed air that has been subjected to temperature control and drying to the inside of the support holder 11 through the connecting part 21 and the connecting part 50, the semiconductor laser in the light source part can be cooled and dehumidified, and the operation of the semiconductor laser is guaranteed. Can be secured.

  In addition, by supplying compressed air that has been subjected to temperature control and drying to the casing 34, the inside of the casing 34 is reliably cooled and dehumidified to ensure the operation of the camera 33 and to receive light from the camera 33. Since the sensitivity characteristic of the element can be kept constant, stable photographing can be performed.

  Further, as shown in FIG. 5, a nozzle 52 that ejects compressed air toward the transparent protective material 26 is provided in the middle of the connecting portion 50, and the outer surface of the transparent protective material 26 is air purged by the compressed air ejected from the nozzle 52. By doing so, it is possible to prevent dust from adhering to the outer surface of the transparent protective material 26, and it is possible to prevent dust from obstructing the photographing field of view.

  In addition, as shown in FIG. 6, a branch tube 54 branched from the first air supply tube 31 is provided at a position above the transparent protective material 26 and provided with a jet outlet 53 for jetting compressed air along the outer surface of the transparent protective material 26. It is also possible to connect to the spout 53. Also in this case, the outer surface of the transparent protective material 26 is purged with compressed air ejected from the ejection port 53, whereby dust can be prevented from adhering to the outer surface of the transparent protective material 26, and the dust obstructs the field of view. Can be prevented.

  In the above-described embodiment, the light source unit 16 is disposed inside the irradiation unit 10 located in front of the imaging unit 20. However, the optical fiber in which the light source unit 16 is disposed behind the imaging unit 20 and connected to the light source unit 16. May be arranged to irradiate the cone mirror 3 with the laser beam to the vicinity of the cone mirror 3 of the irradiation unit 10. In this case, the optical fiber is preferably wired in the hollow portion 51 of the connecting portion 50.

DESCRIPTION OF SYMBOLS 10 Irradiation part 11 Support holder 12 Protective case 13 Cover 14 Bolt 15 Conical mirror 20 Imaging part 21 Connection part 22 Lens part 23 Camera part 24 Hood 25 Flange 26 Transparent protective material 27 Bolt / nut 28 Laser power cable 29 Wiring connector 30 1st DESCRIPTION OF SYMBOLS 1 Air blowing port 31 1st air supply tube 32 Camera lens 33 Camera 34 Casing 35 2nd air blowing port 36 2nd air supply tube 50 Connection part 51 Hollow part 52 Nozzle 53 Outlet 54 Branch tube 60 Insertion rod 61 Base part 71 Compressor 72 Temperature adjustment mechanism (air conditioner)
73 Air dryer 74 Regulator 111 Hole 112 Bolt 113 Opening

Claims (3)

A light source light emitted from a light source part, which has a light source part that emits light source light and is used for photographing an inner surface of the object facing the inner space of the object along a direction in which the object enters and leaves the inner space. An irradiating unit that radiates light toward the inner surface of the object as a radial irradiation light, and an imaging unit that continuously shoots the light cutting surface of the inner surface of the object illuminated by the irradiation light along the direction of withdrawal And a connecting part for connecting the irradiation part and the photographing part,
The imaging unit is located in the central region of the imaging field of view of the imaging device, and the transparent protective material disposed in the imaging field of view of the imaging unit covers the front of the imaging device in a direction across the connection unit,
The connecting part has a hollow part communicating the irradiation part and the photographing part and is fixed through the transparent protective material,
The inner surface photographing apparatus according to claim 1, wherein a wiring to the irradiation unit is inserted into a hollow portion of the connection unit .   The inner surface photographing apparatus according to claim 1, wherein the connecting portion is made of a resin or metal pipe body.   The inner surface photographing apparatus according to claim 1, wherein the transparent protective material is made of sheet glass.

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