JP2978017B2 - Foreign matter detection device for power cable connection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting mold for covering a connecting portion of a plastic insulated cable in a cableway or a manhole at a cable construction site, and a plastic for forming a reinforcing insulator in the casting mold. Using an extruder for extruding the material, in a device for forming an extrusion-molded reinforcing insulator on the connection portion, when foreign matter is mixed into the plastic material injected into the casting mold, The present invention relates to a foreign-matter inspection member for a power cable connecting portion that facilitates confirmation of the foreign matter.

[0002]

2. Description of the Related Art Crosslinked polyethylene insulated cables (hereinafter C)
A plastic insulated cable typified by a V cable is used for a high-voltage transmission line or the like, and when laid in a tunnel or the like, a long cable is sequentially connected to form a transmission line. Like that. Therefore, when laying the CV cable, it is necessary to connect the conductor in the cave or in the manhole portion, and to cover the connection portion with a plastic material and to use a means for forming an insulating coating. Has been done. In order to connect the CV cable, for example, an apparatus as shown in JP-B-63-37469 is used.

In the apparatus shown in the above-mentioned conventional example, an apparatus combining an extruder and a casting mold is disposed in a sinus or a manhole serving as a connection section of a CV cable, and the apparatus is used in a clean room environment. Inside, a mechanism is configured to operate in a state where dust and the like do not enter and to cover the periphery of the connection portion of the CV cable by extrusion. Also, for example,
In the three-phase AC high-voltage power transmission path, it is necessary to form a similar reinforcing insulator for three CV cables. Means such as continuous operation are used.

[0004] However, such an apparatus as shown in the conventional example is disposed in a clean room and is used in an environment in which dust and other harmful substances do not enter from the outside. There is a concern that the waste may be included in the injection material. If a foreign material is mixed in the injection material and the reinforcing insulator is formed by solidifying the plastic material mixed with the foreign material, a state where the insulating performance cannot be sufficiently exhibited occurs. Conventionally, inspection using X-rays has been performed after the formation of the reinforcing insulator. However, there has been a problem that fibrous foreign substances cannot be detected by X-rays.

[0005]

On the other hand, it has been considered to use means for preventing foreign substances from being mixed into the material of the reinforcing insulator at the stage of injecting the plastic material. For this purpose, for example, for a casting mold for forming the reinforcing insulator, an injection machine is used to inject a plastic material from an extruder through an injection pipe. The tube is constituted by a glass tube or the like, and the plastic material injected through the glass tube is to be monitored.

However, when a means for passing a plastic material through a glass tube is used, the strength of the glass tube may become a problem. In other words, the plastic material supplied from the extruder is applied with a pressure of about 10 kg / cm 2 at the final stage of the pouring operation.
The material heated to 110 to 140 ° C. or higher flows in the glass tube. Therefore, as described above, when flowing a material to which a large pressure is applied at a high temperature in a glass tube, a problem is likely to occur in the durability of the glass.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned drawbacks of the conventional detecting device, in which a plastic material is passed through a transparent detecting tube member, and foreign matter is detected by using a laser sensor or a CCD camera. In this case, it is an object of the present invention to provide a device capable of safely protecting the detection tube member and preventing scattering of a plastic material.

[0008]

SUMMARY OF THE INVENTION The present invention provides a casting mold for covering a connecting portion of a plastic material insulated cable, and a method for extruding a plastic material for forming a reinforcing insulator into the casting mold. The present invention relates to an apparatus for forming an extrusion-molded reinforcing insulator at a connection portion of the cable using an extruder. The invention according to claim 1 of the present invention comprises a high-transparency tempered glass tube or a quartz tube for detecting an injected plastic material passing through the extruder and a part of an injection conduit communicating the die. A metal casing member having a detection window is provided so as to connect the detection tube member and surround the detection tube member, and detect foreign matter mixed in the injected plastic material corresponding to the window of the metal casing member. A laser sensor or a CCD camera is provided.

According to a second aspect of the present invention, a protection member made of a transparent or translucent fluororesin tube for protecting the detection tube member is provided around the detection tube member. .

According to a third aspect of the present invention, a protection member made of a transparent or translucent fluororesin tube for protecting the detection tube member is provided around the detection tube member so as to cover the detection tube member. Between the metal casing,
A transparent or translucent tubular protective member is disposed.

[0011] With the above-described configuration, in the detection tube device of the present invention, even if the glass tube is broken, it is possible to prevent the high-temperature and high-pressure plastic material from being scattered to the surroundings. Disasters can be prevented and the safety of the detection device can be ensured. In addition, the plastic material injected into the casting mold can be observed with the naked eye, and the detection operation can be performed in a favorable state not only for foreign matter such as metal but also foreign matter such as fiber. Then, the image taken by using the CCD camera can be confirmed later, so that the quality of the reinforcing insulator after molding can be guaranteed.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing a foreign matter inspection member of a power cable connecting portion according to the present invention. The example shown in FIG. 1 shows a detection tube device 20 arranged in the detection unit 14 with respect to the device shown in FIG. 5 described later. Similar to a conventional glass tube, a CCD camera or the like is provided around the detection tube device. Is used as a mechanism for monitoring the plastic material injected into the casting mold. The detection tube device 20 shown in FIG. 1 has a triple tube member arranged concentrically as shown in FIG. 2 as an AA cross section, and a glass tube 30 for flowing a plastic material. Is
It uses a highly transparent tempered glass, quartz tube, or the like, so that the state of the plastic material flowing in the tube can be visually discriminated from the outside or can be captured by a CCD camera. In addition, a protective member 33 made of a transparent or translucent fluororesin tube or the like is integrally coated around the glass tube 30 so as to cope with a case where the glass tube is broken.

A protective member 35 made of a transparent or translucent acrylic resin tube or the like is disposed concentrically around the glass tube 30, and a metal casing member 36 is disposed around the protective member 35. , And constitutes protection means for the glass tube. Further, an elongated oval window 37 is provided in a predetermined position of the casing member 36 in the axial direction, and the CCD cameras 18 and 18a are respectively arranged in the windows 37, and the focal depth of the CCD camera is adjusted. The state of the plastic material flowing in the glass tube can be detected. In addition, when the glass tube is broken in the middle of flowing a high-pressure material, the two tubular members of the protection member 33 and the protection member 35 disposed around the glass tube 30 are made of plastic material or broken glass. Is prevented from scattering outside from the window 37 of the casing member 36. Therefore, for example, if sufficient strength can be exhibited only by the protection member 33, there is no need to provide the protection member 35, and only one of the protection members may be provided.

As shown in FIG. 2, a plurality of pipe members are concentrically arranged and fixedly held, and are connected to an injection pipe of an extruder and a casting mold as shown in FIG. Thus, the upper member 21 and the lower member 40 are arranged. Then, the outer casing member 36 of the tube member is connected to the set screw 3.
8 and 39, and the tubular member 35 inside the casing member 36 is fixed and held. An upper pipe 25 is provided on the upper part of the upper member 21 so as to protrude therefrom, and a cap nut 22 is disposed above the upper pipe 25.
A mechanism for connecting the injection tube via the. With respect to the upper member 21, a lower member 40 disposed below the tube member for detection is provided with a mounting screw portion 41 protruding from a lower portion of the main body, and a casting die is provided via the mounting screw portion 41. It can be mounted on a mold or mounted on a mold connection tube.

As described above, the members 21 and 40 arranged above and below the tube member are provided with through-holes having the same diameter as the inner diameter of the glass tube 30, and the plastic material flows through the through-holes. Will be able to. Also, the upper member 21 and the lower member 40 are provided with insertion holes 28 and 43 corresponding to the outer diameter of the glass tube 30, and are sealed by packings 31 and 32 arranged above and below the insertion holes. doing. Further, packings 31a and 31b disposed on the inner peripheral surface of the insertion hole 28 of the upper member 21 and packings 32 disposed on the inner peripheral surface of the insertion hole 43 of the lower member 40
Using a and 32b, a mechanism for sealing between the upper and lower members and the glass tube 30 is configured. As the packing, a ring-shaped one made of a fluororesin can be used, and the packing can be adapted to a high-temperature plastic material flowing in the device.

The tubular protective member 35 disposed outside the glass tube 30 is locked and held by engaging steps 29 and 44 provided on the upper member 21 and the lower member 40.
The outer diameters of 9 and 44 are configured to match the inner diameter of the tubular protection member 35. The upper and lower members 21 and 40
The glass tube 30 and the tubular protective member 35 are attached between the two, the respective tube members are positioned, and the casing member 36 is fixed to the outside thereof using set screws 38, 39,. 20. Accordingly, the members constituting the detection tube device are integrally formed via the casing member, and the detection tube device 20 can be handled independently as one member.
In the detection tube device 20 assembled as described above, the casing member 36 is provided with a predetermined number of vertically long windows 37 at predetermined positions around the casing member 36. A detecting device such as a CCD camera is arranged so that the plastic material flowing in the pipeline can be monitored.

In the detection tube device 20 of the present invention configured as described above, the upper tube 25 projecting from the upper member 21 is connected to the injection tube from the extruder via the cap nut 22. In addition, by connecting to the connection pipe 7 of the casting mold using the mounting screw part 41 protruding from the lower part of the lower member 40, the detection part is configured at a predetermined position of the injection pipe of the plastic material. To be able to If a portion where the material stays at the connection portion of the pipe is formed at the time of connecting the pipe, a problem may occur in the injection operation of the plastic material. Therefore, in the detection tube device of the present invention, as shown in FIGS. 3 and 4, a means for preventing the plastic material from staying at the connection portion of the pipeline is configured.

The example shown in FIG. 3 shows the structure of the part connecting the injection pipe 11 and the upper pipe 25.
At the end of the injection pipe 11, a tapered portion 12 is provided which is inclined from the outside to the inside in the direction in which the material flows. Also, a tapered portion 26 is formed at the connection end of the upper pipe 25 in correspondence with the tapered portion 12 of the injection pipe. It constitutes a guidance route. The cap nut 22 used to connect the two conduits 11 and 25 can be configured in the same manner as a commonly used cap nut, and the large-diameter portion 2 formed at the distal end of the upper pipe 25 is used.
The threaded portion 23 is screwed into the threaded portion of the injection tube 11 in a state where the threaded portion 7 is engaged with the locking portion 24 provided integrally with the lower portion of the upper tube, thereby making the connection. Then, as shown in FIG. 3, the connecting portion between the two pipe members is formed in a tapered shape, and the material is set in a shape in which the material does not stay in the tapered portion, so that the fluidity of the plastic material is maintained satisfactorily. Can be done.

In the example shown in FIG. 4, a mechanism for connecting the lower member 40 and the connection pipe 7 of the casting mold is shown. It is also possible to use a configuration in which the mounting screw portion 41 of the lower member 40 is directly screwed into the injection hole of the casting mold without using the mold connection pipe. In the example shown in FIG. 4, a screw hole 8 connected to the injection through hole and corresponding to the mounting screw portion 41 is provided at the tip of the mold connection pipe 7. Further, a tapered portion 42 is formed at the tip of the mounting screw portion 41. The inclined state of the tapered portion 42 is similar to that of the tapered portion in FIG. It is formed so as not to stay.

When monitoring the state of a plastic material using the detection tube device of the present invention configured as described above, a polyethylene resin mixed with or not mixed with a cross-linking material is used as the plastic material. The flow rate in the pipeline is set to several tens cm per minute. Therefore, a skilled technician can easily confirm a state in which a foreign material is mixed in the plastic material while irradiating light from a transparent window portion of the detection tube device. Time to mold
Since it takes about 60 minutes, visual monitoring is difficult. Therefore, as described above, a device such as a laser line sensor and a CCD camera is provided in the window of the detection tube device and recorded by a device such as a VTR, thereby forming a reinforcing insulator during the operation. In addition, after the operation, means for detecting the size of the foreign matter and confirming that the foreign matter has not been mixed in the plastic material can be used.

The example shown in FIG. 5 shows the overall configuration of an apparatus provided with the detecting means of the present invention. The device for arranging this inspection mechanism is configured as a device for forming a reinforcing insulator made of a plastic material with respect to a connection portion of a cable, and is extruded with respect to a casting mold 5 for forming the reinforcing insulator. A mechanism for injecting a plastic material from the machine 10 via an injection pipe 11 is configured. In the apparatus, a glass tube 15 is arranged between the injection tube 11 and the casting mold 5, and a detection unit for detecting foreign matter with respect to the glass tube 15 by a laser line sensor 16 and a CCD camera 18. 14.

The laser line sensor 16 of the two detecting devices constituting the detecting section 14 is connected to the detecting device 17 so as to detect minute foreign matter mixed in the plastic material. In addition, CCD camera 1
Reference numeral 8 is connected to an image recording / analyzing device 19 such as a television device or a video tape device. Then, by combining the above-described devices and forming the detection unit, even if foreign matter is mixed in the plastic material forming the reinforcing insulator,
The presence of the foreign matter can be accurately detected, and the reinforcing insulator is not formed with the foreign matter that cannot maintain the insulating property mixed therein.

In the casting mold 5, one in which the conductors are connected to each other by the conductor connection pipe 3 while the conductor 2 is exposed with the insulating coating of the two cables 1 and 1 a removed. It is accommodated, and a reinforcing insulator is formed around the connection portion. The casting mold 5 is formed as a split mold, and the connection portion of the cable is installed and sealed in the injection space, and a plastic material is press-fitted to form a reinforcing insulator. To be able to The shape of the reinforcing insulator is defined by an injection space 6 of the casting mold 5. A mold connecting pipe 7 is provided in the space 6 for injecting a plastic material into the extruder. 10
The detection unit 14 is disposed on a glass tube 15 connected between the mold connection tube 7 and the injection tube 11.
Even when foreign matter is mixed in the injection material, the foreign matter can be detected.

In the detection tube apparatus shown in the above embodiment of the present invention, since the periphery of the material flow path by the glass tube is covered by a plurality of tube members, the high-temperature material flowing through the glass tube can be used. Is less affected by the cooling action, and the fluidity of the material is not affected. And
When the operation of injecting the plastic material into one casting mold is completed, the detecting tube device is removed from the casting mold and cleaned, and can be used for the next work. In the embodiment of the detection tube device, the diameter of the glass tube or the reinforcing tube can be arbitrarily selected according to the injection amount of the material per unit time, and the material strength and the like of each constituent material. Also, any one can be selected and used.

[0025]

As described above, the foreign matter inspection member for the power cable connection portion of the present invention is constructed as described above, so that even if the glass tube is broken, the high-temperature and high-pressure plastic material is scattered around. It is possible to prevent man-made disasters and to ensure the safety of the detection device. Also, for the plastic material injected into the casting mold,
Not only can it be observed with the naked eye, but also it is possible to perform a good detecting action on foreign substances such as fibers as well as metallic foreign substances. Then, the image taken using the laser line sensor and the CCD camera can be confirmed later, so that the quality of the reinforcing insulator after molding can be guaranteed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a detection tube device of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an explanatory diagram showing a configuration of a connection portion on an upper part of the detection tube device.

FIG. 4 is an explanatory diagram showing a configuration of a lower connection portion of the detection tube device.

FIG. 5 is an explanatory view showing a configuration of a molding apparatus for a reinforcing insulator of the present invention.

[Explanation of symbols]

1 cable, 5 casting mold, 7 mold connecting pipe, 10 extruder, 11 injection pipe, 14 detection unit, 15 glass tube, 16 laser line sensor, 18 CCD camera, 19 image recording device, 20 detection tube device, 21 Upper member, 22
Cap nut, 25 upper tube, 30 glass tube,
31, 32 packing, 33 protective member, 35
Protective member, 36 Casing member, 40
Lower member, 41 mounting screw part, 42 taper part.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-6-88786 (JP, A) JP-A-3-30927 (JP, A) JP-A-2-273455 (JP, A) JP-A-63-1988 277989 (JP, A) JP-A-62-127651 (JP, A) JP-A-60-208072 (JP, A) JP-A-59-117079 (JP, A) JP-A-59-40146 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 39/24 B29C 39/44 B29C 43/34 F16L 15/04 G01N 21/84-21/85 G01N 21/88-21/89 G01V 9 / 04 H01B 9/00 H01R 4/70 H01R 43/00 H02G 1/14

Claims (3)

(57) [Claims] The present invention relates to a casting mold for covering a connecting portion of a plastic material insulated cable, and an extruder for extruding a plastic material for forming a reinforcing insulator into the casting mold. An apparatus for forming an extrusion-molded reinforcing insulator in a portion, wherein a part of an injection pipe communicating with the extruder and a mold is provided with a highly transparent tempered glass tube for detecting an injection plastic material passing through the pipe. Alternatively, a detection tube member made of a quartz tube is connected, and a metal casing member having a detection window is provided so as to surround the detection tube member. The metal casing member is mixed with the injected plastic material corresponding to the window of the metal casing member. A foreign matter detection device for a power cable connection portion, wherein a laser sensor or a CCD camera for detecting a foreign material to be detected is arranged. 2. The sensor according to claim 1, wherein a periphery of the detection tube member is covered with a protection member made of a transparent or translucent fluororesin tube for protecting the detection tube member. Foreign matter detection device at the power cable connection. 3. A protection member made of a transparent or translucent fluororesin tube for protecting the detection tube member is provided around the detection tube member so as to cover the detection tube member and the metal casing. The foreign matter detection device for a connection part for a power cable according to claim 1, wherein a transparent or translucent tubular protective member is disposed between the two.