Power cable connection device and method for manufacturing power cable connection device

Abstract

To provide a power cable connection device and a method for manufacturing a power cable connection device that can reduce the stress generated in a porcelain tube while suppressing the complexity of the manufacturing process.SOLUTION: A power cable connection device 1 comprises a porcelain tube 22, a pipe member 21, which is arranged inside the porcelain tube 22 and into which a power cable 10 is inserted, and a mounting member 23 arranged to enclose the pipe member 21 from the periphery and fitted to the porcelain tube 22 so that a mounting surface 234 to be attached to another member is exposed from the porcelain tube 22. A method for manufacturing the power cable connection device 1 has a step for forming the porcelain tube 22 integral with the pipe member 21 into which the power cable 10 is inserted, and a step for fitting the mounting member 23 to the porcelain tube 22 up to the position of the periphery of the pipe member 21 after forming the porcelain tube 22.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a power cable connection device and a method for manufacturing the power cable connection device. [Background technology]

[0002] Patent Document 1 discloses a power cable connection device for connecting a power cable to other electric wires, etc. The power cable connection device described in Patent Document 1 includes a porcelain tube, a pipe member disposed inside the porcelain tube and into which a power cable is inserted, and an embedded member surrounding the pipe member from the outer periphery side and embedded in the porcelain tube. The porcelain tube has a first semiconductive portion at the interface with the pipe member, and a second semiconductive portion at the interface with the embedded member.

[0003] The power cable connection device described in Patent Document 1 provides a release agent on the surface of the buried member facing the pipe member to suppress adhesion between the buried member and the porcelain tube, thereby suppressing the generation of stress due to differences in thermal expansion coefficients among the porcelain tube, the buried member, and the pipe member in a portion of the porcelain tube located between the buried member and the pipe member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-128719 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, a release agent is used to suppress stress on the porcelain insulator tube, which may complicate the manufacture of the power cable connection device.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a power cable connection device and a manufacturing method for a power cable connection device that can reduce stress generated in a porcelain tube while preventing the manufacturing process from becoming complicated. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the present invention provides a power cable connection device comprising a porcelain tube, a pipe member arranged inside the porcelain tube and into which a power cable is inserted, and an attachment member arranged to surround the pipe member from the outer periphery and fitted into the porcelain tube so that an attachment surface to be attached to another member is exposed from the porcelain tube.

[0008] In addition, in order to achieve the above-mentioned object, the present invention provides a manufacturing method for a power cable connection device, comprising the steps of: forming a porcelain tube integral with a pipe member into which a power cable is inserted; and, after the porcelain tube is formed, fitting an attachment member into the porcelain tube up to a position on the outer periphery of the pipe member. Effect of the Invention

[0009] According to the present invention, it is possible to provide a power cable connection device and a method for manufacturing a power cable connection device that can reduce stress generated in a porcelain tube while suppressing the manufacturing process from becoming complicated. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of a power cable connection device in a first embodiment. [Diagram 2] FIG. 2 is an enlarged view of the mounting member and its periphery in FIG. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. [Figure 4] 3 is a cross-sectional view of the porcelain tube unit and the mounting member before they are assembled together in the first embodiment. FIG. [Diagram 5]3 is a cross-sectional view of the porcelain tube unit and the mounting member in a state where the mounting member is in contact with a raised portion in the first embodiment. FIG. [Figure 6] 3 is a cross-sectional view of the porcelain tube unit and the mounting member after assembly in the first embodiment. FIG. [Figure 7] 11 is an enlarged cross-sectional view of a portion of a power cable connection device according to a second embodiment. FIG. [Figure 8] 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] FIG. 11 is a perspective view of a mounting member in the second embodiment. [Figure 11] 13 is a cross-sectional view passing through two split portions in a power cable connection device according to a third embodiment. FIG. [Figure 12] 12 is a cross-sectional view taken along line XII-XII in FIG. 11. [Figure 13] 13 is a cross-sectional view passing through two split portions in a power cable connection device according to a fourth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [First embodiment] A first embodiment of the present invention will be described with reference to Figures 1 to 6. Note that the embodiment described below is shown as a preferred specific example for carrying out the present invention, and while there are some parts that specifically exemplify various technical matters that are technically preferable, the technical scope of the present invention is not limited to this specific embodiment.

[0012] (Power cable connection device 1) FIG. 1 is a cross-sectional view of a power cable connection device 1 in this embodiment. As shown in FIG. 1, the power cable connection device 1 includes a main body 2, a cover 3, and a connection portion 4. The main body 2 ensures electrical insulation between the stepped stripped power cable 10 and members arranged around the power cable 10. The cover 3 covers a part of the main body 2. The connection portion 4 is a member for connecting the power cable 10 to the outside of the power cable connection device 1. Hereinafter, the direction in which the central axis of the power cable 10 (i.e., the dashed line in FIG. 1) extends is referred to as the axial direction X. Also, the side of the power cable 10 in the axial direction X that is connected to the connection portion 4 is referred to as the tip side X1, and the opposite side is referred to as the base side X2.

[0013] (Main body 2) The main body 2 includes a pipe member 21, a porcelain tube 22, a mounting member 23, and a flange member 24.

[0014] The pipe member 21 is made of a metal such as brass or an aluminum alloy, and is formed into a long cylindrical shape in the axial direction X. The pipe member 21 is made of a material having higher rigidity than the porcelain tube 22. The pipe member 21 is disposed on the inner periphery side of the porcelain tube 22, and reinforces the porcelain tube 22, which has flexibility.

[0015] An end portion on the tip side X1 of the pipe member 21 protrudes from the porcelain tube 22 and is electrically connected to the power cable 10 via a connection portion 4 described later. In addition, an end portion on the base side X2 of the pipe member 21 radially faces the mounting member 23 via the porcelain tube 22. The pipe member 21 is formed so that the inner diameter is larger than the outer diameter of a portion of the power cable 10 that is disposed inside the pipe member 21. This makes it easier to insert the power cable 10 into the pipe member 21.

[0016] The porcelain tube 22 includes an insulator 220 and semiconductive portions provided on the surface of the insulator 220 (in this embodiment, a first semiconductive portion 221, a second semiconductive portion 222, and a third semiconductive portion 223).

[0017] The insulator 220 is made of, for example, a polymer material formed into a tubular shape and has flexibility. Examples of the polymer material constituting the insulator 220 include silicone rubber, ethylene propylene rubber (EPM), and ethylene propylene diene rubber (EPDM). In particular, by using a material having a relatively high tear strength as the material of the insulator 220, it becomes easier to suppress the occurrence of cracks in the insulator 220. In addition, by using a material having a relatively low elastic modulus as the material of the insulator 220, it becomes easier to insert the power cable 10 into the insulator 220. In a free state before the cable is inserted into the insulator tube 22, a portion of the inner circumferential surface of the porcelain tube 22 on the base end side X2 from the pipe member 21 is smaller than the outer diameter of the power cable 10 inserted therein, and the power cable 10 is inserted into the porcelain tube 22 while expanding the portion of the inner circumferential surface of the porcelain tube 22 on the base end side X2 from the pipe member 21.

[0018] On the outer periphery of the insulator 220, annular umbrella portions 220a protruding toward the outer periphery are provided at a predetermined interval at multiple locations in the axial direction X. By forming multiple umbrella portions 220a on the insulator 220, it is possible to ensure a creeping distance on the outer periphery of the insulator 220, and it is possible to suppress the occurrence of creeping discharge along the surface of the insulator 220.

[0019] A cylindrical hole 220b that is open to the base end side X2 is formed on the outer circumferential side of the pipe member 21 in the insulator 220. The mounting member 23 is fitted into the hole 220b with a third semiconductive portion 223 interposed therebetween.

[0020] The insulator 220 is formed by insert molding in which the pipe member 21, the first semiconductive portion 221, the second semiconductive portion 222, and the third semiconductive portion 223 are placed in a mold. As a result, the insulator 220 is formed so as to be fixed to each of the pipe member 21, the first semiconductive portion 221, the second semiconductive portion 222, and the third semiconductive portion 223.

[0021] The first semiconductive portion 221, the second semiconductive portion 222, and the third semiconductive portion 223 are made of an elastic semiconductive material, for example, silicone rubber, EPM, EPDM, etc., with conductive powder such as carbon dispersed therein to impart conductivity. The first semiconductive portion 221, the second semiconductive portion 222, and the third semiconductive portion 223 suppress electric field concentration in the surroundings.

[0022] The first semiconductive part 221 is provided in a film shape on the inner peripheral surface of the insulator 220, and is interposed between the insulator 220 and the pipe member 21. The first semiconductive part 221 is formed in a cylindrical shape so as to surround the pipe member 21 from the outer peripheral side, except for the tip portion. The first semiconductive part 221 has a part extended to the base end side X2 of the pipe member 21, and this part is interposed between the power cable 10 inserted inside the pipe member 21 and the insulator 220. The first semiconductive part 221 is formed, for example, by insert molding in which the pipe member 21 is placed in a mold. As a result, the first semiconductive part 221 is fixed to the pipe member 21.

[0023] The second semiconductive portion 222 is formed on the inside of the end portion on the base end side X2 of the insulator 220, and has an annular shape. The second semiconductive portion 222 contacts the outer circumferential surface of the power cable 10 inserted into the porcelain tube 22. The second semiconductive portion 222 is formed by molding or the like.

[0024] The third semiconductive portion 223 is formed in a film shape at least on the inner surface of the hole 220b of the insulator 220, and is interposed between the insulator 220 and the mounting member 23. In this embodiment, the third semiconductive portion 223 extends to the base end side X2 beyond the hole 220b on the outer circumferential surface of the insulator 220. The third semiconductive portion 223 is formed, for example, by molding.

[0025] FIG. 2 is an enlarged view of the periphery of the mounting member 23 in FIG. 1. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2. As shown in FIG. 2, a portion formed on the inner surface of the hole 220b of the insulator 220 in the third semiconductive portion 223 forms a fitting hole 223a. The fitting hole 223a is a hole for mounting the mounting member 23. In this embodiment, the fitting hole 223a has a first cylindrical hole portion 223b formed in a cylindrical shape and a second cylindrical hole portion 223c formed on the base end side X2 of the first cylindrical hole portion 223b and having an outer diameter larger than that of the first cylindrical hole portion 223b. The first cylindrical hole portion 223b is a hole into which a cylindrical portion 231 of the mounting member 23 described later is fitted, and the second cylindrical hole portion 223c is a hole into which a protrusion portion 232 of the mounting member 23 described later is fitted. The fitting hole 223a is formed in a shape that conforms to the surface of the portion of the mounting member 23 that is to be fitted into the fitting hole 223a.

[0026] The third semiconductive portion 223 has a protruding portion 223d that protrudes toward the outer periphery and faces the mounting member 23 from the base end side X2 on the base end side X2 of the mounting member 23. The protruding portion 223d serves as a retainer that prevents the mounting member 23 from coming out of the fitting hole 223a. The protruding portion 223d is located closer to the base end side X2 than the fitting hole 223a. It is also possible to omit the protruding portion 223d.

[0027] The outer diameter of the portion of the porcelain tube 22 on the base end side X2 from the raised portion 223d is smaller than the inner diameter of the mounting member 23. Therefore, when the mounting member 23 is fitted into the fitting hole 223a from the base end side X2 of the porcelain tube 22, the mounting member 23 can be moved without requiring a strong force, at least until the mounting member 23 reaches the raised portion 223d.

[0028] 2 and 3, the mounting member 23 is formed in a tubular shape so as to surround from the outer periphery a portion of the base end side X2 of the pipe member 21. As shown in Fig. 2, the mounting member 23 includes a tubular portion 231 formed in a cylindrical shape, and an annular protruding portion 232 formed to protrude from the end of the base end side X2 of the tubular portion 231 to the outer periphery.

[0029] The mounting member 23 is made of a material having higher rigidity than the porcelain tube 22, for example, a metal such as brass or an aluminum alloy, and is connected to a ground potential when the power cable connection device 1 is in use. The thermal expansion coefficients of the pipe member 21 and the mounting member 23 are each smaller than the thermal expansion coefficient of the insulator 220.

[0030] The mounting member 23 is fitted into the porcelain tube 22. Specifically, the mounting member 23 is fitted into the porcelain tube 22 by being inserted into a fitting hole 223a of the porcelain tube 22. More specifically, the mounting member 23 is press-fitted into the fitting hole 223a. That is, in a state where the mounting member 23 is not inserted into the fitting hole 223a (i.e., in a free state), the size of the fitting hole 223a is smaller than the size of a portion of the mounting member 23 that is inserted into the fitting hole 223a, and the mounting member 23 is inserted into the fitting hole 223a while pushing and widening the fitting hole 223a.

[0031] In this way, the mounting member 23 is later assembled to the porcelain tube 22 by fitting, so that the mounting member 23 comes into contact with the inner surface of the fitting hole 223a, but the entire surface of the mounting member 23 is not fixed to the inner surface of the fitting hole 223a. Unlike this embodiment, if the mounting member 23 is fixed to the fitting hole 223a, the inner circumferential side of the portion of the porcelain tube 22 between the pipe member 21 and the mounting member 23 is fixed to the pipe member 21 and the outer circumferential side of the portion of the porcelain tube 22, and expansion and contraction to both the inner circumferential side and the outer circumferential side are hindered, and stress is likely to increase. On the other hand, if the mounting member 23 and the porcelain tube 22 are not fixed to each other as in this embodiment, the outer circumferential side of the portion of the porcelain tube 22 between the pipe member 21 and the mounting member 23 is prevented from being pulled by the mounting member 23, and stress is reduced.

[0032] The corners of the portion of the surface of the mounting member 23 that comes into contact with the inner surface of the fitting hole 223a are rounded to improve adhesion with the inner surface of the fitting hole 223a. Also, the end of the base end side X2 of the inner circumferential surface of the mounting member 23 forms an inclined surface 233 that increases in diameter toward the base end side X2. This increases the angle between the inclined surface 233 and a mounting surface 234 described below, improving adhesion between the periphery of the inclined surface 233 on the surface of the mounting member 23 and the inner surface of the fitting hole 223a.

[0033] The surface of the base end side X2 of the mounting member 23 constitutes a mounting surface 234 to be attached to the flange member 24. The mounting surface 234 is exposed from the porcelain tube 22 when the mounting member 23 is assembled to the porcelain tube 22. In this embodiment, in addition to the mounting surface 234, the outer peripheral surface of the protruding portion 232 of the mounting member 23 is also exposed from the porcelain tube 22, and the other surfaces are in close contact with the inner surface of the fitting hole 223a. The mounting member 23 is formed with a female threaded hole 235 that opens into the mounting surface 234. A bolt B1 for fixing the flange member 24 to the mounting member 23 is screwed into the female threaded hole 235.

[0034] The flange member 24 is formed in an annular shape. The flange member 24 is fixed to the mounting member 23 by a bolt B1 in a state where the flange member 24 is overlapped on the mounting surface 234. The flange member 24 is formed with a bolt insertion hole 241 through which a bolt (not shown) is inserted for mounting the flange member 24 to the mounting target 100. The flange member 24 is also formed with a female threaded hole 242 that opens on the surface of the base end side X2. A bolt B2 for fixing the cover 3 to the flange member 24 is screwed into the female threaded hole 242. Seal portions 11a and 11b for ensuring watertightness are arranged between the flange member 24 and the mounting member 23 and between the flange member 24 and the cover 3, respectively.

[0035] (Cover 3) 1, the cover 3 is made of brass, aluminum alloy, or the like formed into a cylindrical shape, and covers the outer periphery of the main body 2 protruding from the flange member 24 to the base end side X2. A cover flange 31 protruding to the outer periphery is formed at the end of the tip side X1 of the cover 3. The cover flange 31 is fixed to the flange member 24 by bolts B2.

[0036] The gap between the end of the base end side X2 of the cover 3 and the power cable 10 is sealed by a sealing portion 12. The sealing portion 12 is formed by wrapping a polyethylene tape, an epoxy tape, or the like provided with an adhesive around the outer periphery of the power cable 10, and provides a watertight seal between the cover 3 and the power cable 10.

[0037] (Connection 4) The connection part 4 includes a conductor connecting rod 41, a high voltage shield 42, a fixed terminal 43, and a co-fastening nut 44. The conductor connecting rod 41 has a crimping hole 411 that is open on the base end side X2. The conductor part 101 exposed from the insulating coating of the power cable 10 is inserted into the crimping hole 411, and the end part of the base end side X2 of the conductor connecting rod 41 is crimped toward the conductor part 101. In this way, the conductor connecting rod 41 and the power cable 10 are connected. In addition, the conductor connecting rod 41 has a male screw part 412 that protrudes on the tip end side X1. The male screw part 412 penetrates each of the high voltage shield 42 and the fixed terminal 43.

[0038] The high voltage shield 42 is made of a conductor and has a bottomed cylindrical shape that is open on the base end side X2. The high voltage shield 42 is fitted onto the tip end portion of the pipe member 21 that protrudes from the porcelain tube 22 to the tip end side X1.

[0039] The fixed terminal 43 has a plate shape and overlaps the high voltage shield 42 from the tip side X1. A connection hole 431 for connection to an external electric wire or the like is formed in the fixed terminal 43. The fixed terminal 43 and the high voltage shield 42 are fastened together between the conductor connecting rod 41 and a co-fastening nut 44, whereby the fixed terminal 43, the high voltage shield 42, and the conductor connecting rod 41 are electrically connected to one another.

[0040] (Example of using the power cable connection device 1) Next, a usage example of the power cable connection device 1 of this embodiment will be described. The power cable connection device 1 is attached to, for example, the roof of a railway vehicle. In this case, a wall constituting the roof of the railway vehicle, a case for accommodating the power cable connection device 1 provided on the roof of the railway vehicle, or the like becomes the attachment target 100. The power cable connection device 1 can be used for, for example, electrical connection between adjacent railway vehicles, electrical connection with a pantograph, etc.

[0041] (Manufacturing method of the power cable connection device 1) Next, one example of a method for manufacturing the power cable connection device 1, particularly a method for attaching the attachment member 23 to the porcelain pipe 22, will be described with reference to FIGS.

[0042] 4 is a cross-sectional view of the pipe member 21 and the porcelain tube 22 before they are assembled to the mounting member 23. In the method of mounting the mounting member 23 to the porcelain tube 22 in this embodiment, first, a porcelain tube unit 5 in which the pipe member 21 and the porcelain tube 22 are integrated is prepared. The porcelain tube unit 5 is integrally formed by molding the insulator 220 by insert molding in which the pipe member 21, the first semiconductive portion 221, the second semiconductive portion 222, and the third semiconductive portion 223 are placed in a mold.

[0043] Next, the mounting member 23 is assembled to the porcelain tube 22 from the base end side X2 of the porcelain tube 22 so that the porcelain tube 22 passes inside the mounting member 23. At this time, since the outer diameter of the portion of the porcelain tube 22 on the base end side X2 from the raised portion 223d is smaller than the inner diameter of the mounting member 23, the mounting member 23 can be moved without requiring a strong force until the mounting member 23 contacts the raised portion 223d. Fig. 5 is a cross-sectional view of the porcelain tube unit and the mounting member in a state in which the mounting member 23 abuts against the raised portion 223d.

[0044] After the mounting member 23 abuts against the raised portion 223d, the mounting member 23 is pushed into the tip side X1 so as to overcome the raised portion 223d while elastically crushing it. Then, the mounting member 23 is inserted into the fitting hole 223a while climbing over the raised portion 223d. At this time, since the size of the fitting hole 223a is smaller than the portion of the mounting member 23 disposed in the fitting hole 223a as described above, the mounting member 23 is pressed into the fitting hole 223a while expanding the fitting hole 223a. FIG. 6 is a cross-sectional view showing the porcelain tube unit 5 and the mounting member 23 assembled together. In FIG. 6, the surface position of the third semiconductive portion 223 before deformation is indicated by a two-dot chain line. As described above, the mounting member 23 is fitted into the fitting hole 223a.

[0045] To enable the mounting member 23 to be assembled to the porcelain tube 22 as described above, no protrusion that the mounting member 23 cannot get over is formed on the base end side X2 of the porcelain tube 22 relative to the fitting hole 223a.

[0046] (Functions and Effects of the First Embodiment) In the power cable connection device 1 of this embodiment, the mounting member 23 is fitted into the porcelain tube 22. This prevents the mounting member 23 from being fixed to the porcelain tube 22, and prevents stress caused by the difference in thermal expansion coefficient between the porcelain tube 22 and the mounting member 23 from being generated in the porcelain tube 22.

[0047] Moreover, the mounting member 23 is inserted into a fitting hole 223a formed in the porcelain tube 22. Therefore, the contact area between the mounting member 23 and the porcelain tube 22 increases, and the mounting member 23 is firmly fixed to the porcelain tube 22.

[0048] Moreover, the mounting member 23 is press-fitted into the fitting hole 223a. Therefore, the mounting member 23 is more firmly fixed to the porcelain tube 22. In addition, it is easy to prevent a gap from being formed between the mounting member 23 and the inner surface of the fitting hole 223a.

[0049] Moreover, the porcelain tube 22 has a protruding portion 223d that protrudes toward the outer periphery and faces the mounting member 23 from the base end side X2 on the open side (i.e., the base end side X2) of the fitting hole 223a in the mounting member 23. Therefore, the porcelain tube 22 is prevented from slipping out of the fitting hole 223a to the base end side X2, and the mounting member 23 is firmly fixed to the porcelain tube 22.

[0050] In addition, the outer diameter of the portion of the porcelain tube 22 on the base end side X2 from the raised portion 223d is smaller than the inner diameter of the mounting member 23. Therefore, when assembling the mounting member 23 to the porcelain tube 22, no strong force is required until the porcelain tube 22 reaches the raised portion 223d, and the productivity of the power cable connection device 1 can be improved.

[0051] As described above, according to the present embodiment, it is possible to provide a power cable connection device and a manufacturing method for a power cable connection device that can reduce stress generated in a porcelain tube while suppressing the manufacturing process from becoming complicated.

[0052] [Second embodiment] A second embodiment of the present invention will be described with reference to Figs. 7 to 10. Fig. 7 is an enlarged cross-sectional view of a portion of the power cable connection device 1. Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 7. Fig. 9 is a cross-sectional view taken along line IX-IX in Fig. 7. Fig. 10 is a perspective view of a mounting member 23.

[0053] In this embodiment, the configuration of the mounting member 23 is changed from that of the first embodiment. Specifically, in this embodiment, the mounting member 23 is divided in the circumferential direction at least at one location. This makes the mounting member 23 more likely to be displaced or deformed to follow the thermal expansion and thermal contraction of the porcelain tube 22, and reduces the stress generated in the porcelain tube 22.

[0054] In this embodiment, the mounting member 23 is divided in the circumferential direction at multiple locations, and is composed of multiple divided pieces 230. Specifically, the mounting member 23 is divided in the circumferential direction at two locations, and is composed of two divided pieces 230. Hereinafter, the region divided in the circumferential direction of the mounting member 23 (i.e., the region between the two divided pieces 230 in the circumferential direction of the mounting member 23) is referred to as a divided portion 23a.

[0055] The two divided parts 23a of the mounting member 23 are formed at positions 180° opposite each other in the circumferential direction. In this embodiment, the divided parts 23a are formed parallel to the axial direction X. That is, the mounting member 23 has a shape in which the mounting member in the first embodiment is divided in half in the axial direction X. The mounting member 23 only needs to be divided in the circumferential direction, and the divided parts 23a do not need to be parallel to the axial direction X. The mounting member 23 may also be divided in the circumferential direction at one location or at three or more locations. The fewer the number of divisions of the mounting member 23, the fewer the number of parts constituting the mounting member 23, and the more the number of divisions, the easier it is to reduce the stress generated in the porcelain tube 22. Therefore, the number of divisions can be appropriately determined taking these factors into consideration.

[0056] In this embodiment, the divided portion 23a is configured with a gap. The divided portion 23a is formed as a minute gap that prevents the divided pieces 230 from abutting against each other when the divided pieces 230 thermally expand and contract. For example, the width of the divided portion 23a (e.g., the dimension in the vertical direction in FIG. 7) is smaller than the thickness of the pipe member 21. The divided piece 230 has an arc-shaped portion 231a formed in an arc shape, and a protruding portion 232 formed to protrude from the end of the base end side X2 of the arc-shaped portion 231a toward the outer periphery.

[0057] Before the mounting member 23 is inserted into the fitting hole 223a, the fitting hole 223a is smaller than the divided piece 230. For example, before the mounting member 23 is inserted into the fitting hole 223a, the inner diameter of the inner peripheral surface of the divided piece 230 is smaller than the diameter of the portion of the fitting hole 223a where the inner peripheral surface of the divided piece 230 contacts. Moreover, before the mounting member 23 is inserted into the fitting hole 223a, the outer diameter of the outer peripheral surface of the arc-shaped portion 231a of the divided piece 230 is larger than the diameter of the portion of the fitting hole 223a where the outer peripheral surface of the arc-shaped portion 231a contacts. Moreover, before the mounting member 23 is inserted into the fitting hole 223a, the outer diameter of the protruding portion 232 of the divided piece 230 is larger than the diameter of the portion of the fitting hole 223a where the protruding portion 232 contacts in the radial direction. Then, the divided pieces 230 are inserted into the fitting hole 223a while pushing and widening the fitting hole 223a, which is smaller than the divided pieces 230, thereby ensuring close contact between the divided pieces 230 and the inner surface of the fitting hole 223a. Other configurations of the power cable connection device 1 are similar to those of the first embodiment.

[0058] In the manufacturing method of the power cable connection device 1 of this embodiment, similarly to the first embodiment, the porcelain tube 22 is molded separately from the mounting member 23, and then the two split pieces 230 constituting the mounting member 23 are assembled by being inserted (specifically, press-fitted) into the fitting hole 223a of the porcelain tube 22. As an example, the two split pieces 230 are inserted into the fitting hole 223a at the same time in a state in which they are temporarily fixed to each other by a jig (not shown). This can facilitate the insertion of the two split pieces 230 into the fitting hole 223a. However, this is not limited thereto, and the two split pieces 230 may be inserted into the fitting hole 223a one by one. Other manufacturing methods for the power cable connection device 1 are similar to those in the first embodiment.

[0059] In addition, among the symbols used in the second and subsequent embodiments, the same symbols as those used in the previously described embodiments represent the same components, etc. as those in the previously described embodiments, unless otherwise specified.

[0060] (Functions and Effects of the Second Embodiment) In this embodiment, the mounting member 23 is divided in the circumferential direction at least at one location. Therefore, the mounting member 23 is easily displaced or deformed in accordance with the thermal expansion and contraction of the porcelain tube 22, and the stress generated in the porcelain tube 22 is reduced. In addition, the second embodiment has the same functions and effects as the first embodiment.

[0061] [Third embodiment] A third embodiment of the present invention will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a cross-sectional view passing through two divided portions 23a in the power cable connection device 1. Fig. 12 is a cross-sectional view taken along line XII-XII in Fig. 11.

[0062] This embodiment is an embodiment in which a path sealing portion 6 is further provided in addition to the second embodiment. The path sealing portion 6 is a member that seals the gap S between the flange member 24 and a portion of the porcelain pipe 22 located on the outer circumferential side of the mounting member 23, and the communication path P that passes through the divided portion 23a of the mounting member 23 and communicates between the external space of the power cable connection device 1 and the space inside the cover 3.

[0063] The gap S is formed in the axial direction X between an opposing wall 243 (described later) of the flange member 24 and a portion of the porcelain tube 22 formed on the outer circumferential side of the mounting member 23. The opposing wall 243 is formed to protrude toward the tip side X1 of the flange member 24, faces the outer circumferential surface of the protruding portion 232 of the mounting member 23 in the radial direction, and has an annular shape. The gap S is formed around the entire circumference.

[0064] In this embodiment, the path seal portion 6 is formed to close the gap S from the outer periphery. The path seal portion 6 is formed over the entire circumference and closes the gap S formed over the entire circumference. The path seal portion 6 can be composed of, for example, putty, a tape member, or the like. When the path seal portion 6 is made of putty, as an example, the path seal portion 6 can be disposed in at least a part of the gap S, and is applied so as to straddle the opposing wall 243 and the porcelain tube 22 on the outer periphery side of the gap S. When the path seal portion 6 is made of a tape member, as an example, the path seal portion 6 is wound around at least one circumference so as to straddle the opposing wall 243 and the porcelain tube 22 on the outer periphery side of the gap S. FIG. 11 shows an example in which the path seal portion 6 is made of putty and the path seal portion 6 also enters the gap S, but when the path seal portion 6 is made of a tape member, the path seal portion 6 is not disposed in the gap S, but is disposed only on the outer periphery side of the gap S. The path seal portion 6 may be formed of, for example, both putty and a tape member. In this case, for example, the gap S may be filled with putty, and the outer periphery of the putty may be further wrapped with a tape member.

[0065] In this embodiment, since the communication path P is sealed by the path seal portion 6, there is no need for a seal portion (see reference 11a in Figs. 1 and 2) between the mounting member 23 and the flange member 24. In this embodiment, the space within the cover 3 is ensured to be watertight by the path seal portion 6, the sealing portion (see reference numeral 12 in Fig. 1), and the seal portion 11b. Other configurations of the power cable connection device 1 are similar to those of the second embodiment.

[0066] In the manufacturing method of the power cable connection device 1 of this embodiment, the mounting member 23 is inserted into the porcelain pipe 22, and the flange member 24 is fastened to the mounting member 23 with the bolt B1, and then the communication path P is sealed by the path seal portion 6. Other aspects of the manufacturing method for the power cable connection device 1 are similar to those of the second embodiment.

[0067] (Functions and Effects of the Third Embodiment) The power cable connection device 1 of this embodiment further includes a path seal portion 6 that seals the communication path P. This prevents foreign matter such as moisture from entering the inside of the power cable connection device 1 (for example, the inner space of the cover) through the gap S. In addition, the second embodiment has the same functions and effects as the second embodiment.

[0068] [Fourth embodiment] A fourth embodiment of the present invention will be described with reference to Fig. 13. Fig. 13 is a cross-sectional view of the power cable connection device 1 taken along a line passing through the two split portions 23a.

[0069] In this embodiment, the configuration of the path seal portion 6 is changed from that of the third embodiment. In this embodiment, the power cable connection device 1 includes two path seal portions 6. The two path seal portions 6 are each made of an elastic sheet capable of elastic deformation, and are disposed in the two divided portions 23a. Each path seal portion 6 is disposed in a state compressed in the thickness direction of each path seal portion 6 by the two divided pieces 230. In this embodiment, the path seal portion 6 is disposed in the entire divided portion 23a in which it is disposed, but is not limited thereto, and it is sufficient if it can seal the communication path P. For example, the two path seal portions 6 may be disposed only between the protruding portions 232 of the two divided pieces 230, and may not be disposed between the arc-shaped portions 231a of the two divided pieces 230. If a hard adhesive or the like is formed on the dividing portion 23a, it is possible to seal the path sealing portion 6, but the significance of providing the dividing portion 23a (i.e., stress absorption) is diminished. Therefore, when placing the path sealing portion 6 on the dividing portion 23a, it is preferable that the path sealing portion 6 be deformable (e.g., elastically deformable).

[0070] In this embodiment, unlike the third embodiment, in order to prevent moisture and the like from entering the power cable connection device 1 through the boundary between the mounting member 23 and the flange member 24, a seal portion 11a consisting of an O-ring or the like is disposed between the mounting member 23 and the flange member 24. Other configurations of the power cable connection device 1 are similar to those of the second embodiment.

[0071] In the manufacturing method of the power cable connection device 1 of this embodiment, when the two split pieces 230 are temporarily fixed before being inserted into the fitting hole 223a, the two path seal portions 6 are sandwiched between the two split portions 23a of the two split pieces 230. Then, the two split pieces 230 are inserted into the fitting hole 223a with the two path seal portions 6 sandwiched therebetween. Other aspects of the manufacturing method for the power cable connection device 1 are similar to those of the second embodiment.

[0072] (Functions and Effects of the Fourth Embodiment) In this embodiment, the path seal portion 6 is disposed in the divided portion 23a. Therefore, even if the adhesion between the path seal portion 6 and the porcelain tube 22 is low, it is possible to seal the communication path P. Therefore, even if a material with low adhesiveness is used for the porcelain tube 22, for example, it is easy to seal the communication path P. In addition, the second embodiment has the same functions and effects as the third embodiment.

[0073] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiment will be described by using the reference numerals and the like in the embodiment. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiment.

[0074] [1] A power cable connection device 1 comprising: a porcelain tube 22; a pipe member 21 arranged inside the porcelain tube 22 and into which a power cable 10 is inserted; and an attachment member 23 arranged to surround the pipe member 21 from the outer periphery and fitted into the porcelain tube 22 so that an attachment surface 234 to be attached to another member is exposed from the porcelain tube 22.

[0075] [2] The power cable connection device 1 according to [1], wherein the mounting member 23 is inserted into a fitting hole 223a formed in the porcelain tube 22.

[0076] [3] The power cable connection device 1 according to [2], wherein the mounting member 23 is press-fitted into the fitting hole 223a.

[0077] [4] The power cable connection device 1 described in [2] or [3], wherein the porcelain tube 22 has a raised portion 223d that protrudes outwardly and faces the mounting member 23 from the open side X2 of the fitting hole 223a in the mounting member 23.

[0078] [5] The power cable connection device 1 according to [4], wherein an outer diameter of a portion of the porcelain tube 22 closer to the open side X2 than the raised portion 223d is smaller than an inner diameter of the mounting member 23.

[0079] [6] The power cable connection device 1 according to any one of [2] to [5], wherein the mounting member 23 is divided in the circumferential direction at least at one location.

[0080] [7] The power cable connection device 1 described in [6] further includes a flange member 24 overlapped on the mounting surface 234 of the mounting member 23 and fixed to the mounting member 23, a cover 3 located on the opposite side of the flange member 24 to the mounting member 23 and surrounding the porcelain tube 22, and a path sealing portion 6 that seals a gap S between a portion of the porcelain tube 22 located on the outer periphery of the mounting member 23 and the flange member 24, and a communication path P that passes through a dividing portion 23a of the mounting member 23 to communicate between an external space and a space within the cover 3.

[0081] [8] A method for manufacturing a power cable connection device 1, comprising: a step of forming a porcelain tube 22 integral with a pipe member 21 into which a power cable 10 is inserted; and a step of fitting an attachment member 23 to the porcelain tube 22 up to a position on the outer periphery of the pipe member 21 after the porcelain tube 22 is formed.

[0082] Although the embodiment of the present invention has been described above, the invention according to the claims is not limited to the above embodiment. It should be noted that not all of the combinations of features described in the embodiment are essential to the means for solving the problems of the invention. The present invention can be modified appropriately without departing from the spirit of the invention. [Explanation of symbols]

[0083] 1...Power cable connection device 10...Power cable 21...Pipe member 22...Insulator tube 223a…Mating hole 223d...Protuberance 23...Mounting member 23a...Divided part 234…Mounting surface 24...Flange member 3. Cover 6…Path seal part S…Gap P…Communication path

Claims

1. A porcelain tube and a pipe member disposed inside the porcelain tube and into which a power cable is inserted; and an attachment member that is disposed so as to surround the pipe member from the outer periphery side and is fitted to the porcelain tube so that an attachment surface to be attached to another member is exposed from the porcelain tube. Power cable connection device.

2. The mounting member is inserted into a fitting hole formed in the porcelain tube. The power cable connection device according to claim 1 .

3. The mounting member is press-fitted into the fitting hole.

3. The power cable connection device according to claim 2.

4. The porcelain tube has a protruding portion on an open side of the fitting hole in the mounting member, the protruding portion protruding toward an outer periphery and facing the mounting member from the open side.

4. The power cable connection device according to claim 2 or 3.

5. An outer diameter of a portion of the porcelain tube on the open side of the raised portion is smaller than an inner diameter of the mounting member.

5. The power cable connection device according to claim 4.

6. The mounting member is divided in the circumferential direction at least at one location.

4. The power cable connection device according to claim 2 or 3.

7. a flange member overlapped with the mounting surface of the mounting member and fixed to the mounting member; a cover located on the opposite side of the flange member from the mounting member and surrounding the porcelain tube; a path seal portion that seals a gap between a portion of the porcelain tube located on an outer circumferential side of the mounting member and the flange member, and a communication path that passes through a division portion of the mounting member to communicate between an external space and a space within the cover, 7. The power cable connection device according to claim 6.

8. forming a porcelain tube integral with a pipe member into which a power cable is inserted; and after the porcelain tube is formed, a mounting member is fitted to the porcelain tube up to a position on an outer circumferential side of the pipe member. A method for manufacturing a power cable connection device.

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