JP7025726B2 - Termination connection - Google Patents

Description

The present invention relates to a terminal connection.

Patent Document 1 discloses a cable connection portion for connecting a power cable to a power device such as a transformer. This cable connection includes a bushing, a cable terminal mounted in the bushing receptacle, a stress cone placed between the bushing and the cable terminal, and a stress cone directed toward the tip of the bushing (to the bushing of the cable terminal). It is equipped with a pressing device that presses in the insertion direction). The pressing device is an annular pusher that is pressed against the stress cone, an annular pusher flange that is placed on the rear end side of the pusher, and a coil that is placed between the pusher and the pusher flange. It is equipped with a shaped spring. The pressing device presses the flange portion of the push metal fitting toward the bushing side, so that the urging force due to the spring force of the spring acts on the push metal fitting, and the push metal fitting presses the stress cone against the bushing.

Japanese Unexamined Patent Publication No. 2014-68514

The cable connection (termination connection) may vibrate using an electric power device as a vibration source. When the terminal connection vibrates, abnormal noise may occur due to the vibration. Depending on the tone of the abnormal sound, it is similar to the sound of partial discharge generated due to an electrical defect of the terminal connection portion, and it is difficult to immediately identify the cause of the sound. In addition, when abnormal noise is generated, it is necessary to stop power transmission.

Therefore, one of the purposes of the present disclosure is to provide a terminal connection portion capable of suppressing the generation of abnormal noise.

The terminal connection part according to the present disclosure is
The end of the cable in which the conductor and the cable insulator formed on the outer circumference of the conductor are gradually exposed, and the end of the cable.
A pre-molded insulator that is attached in close contact with the outer circumference of the cable insulator,
A bushing that houses the end of the cable and the premolded insulator,
A pressing device for pressing the premolded insulator from the rear end side to the tip side of the cable is provided.
The pressing device is
A cylindrical member arranged on the outer periphery of the cable insulator, which has a tip portion in contact with the premold insulator and a rear end portion located on the rear end side of the cable with respect to the tip portion. Department and
A plurality of shaft portions having one end fixed to the rear end portion and arranged in parallel with the axial direction of the cable, and a plurality of shaft portions.
A movable flange portion that is arranged on the other end side of the plurality of shaft portions and whose position along the plurality of shaft portions can be adjusted,
An elastic body that is attached to each of the shaft portions and urges the pressing portion to the tip end side of the cable with respect to the movable flange portion.
A vibration absorbing material arranged between each of the shaft portions and the elastic body is provided.

The terminal connection portion can suppress the generation of abnormal noise.

It is a schematic partial vertical sectional view which shows the terminal connection part which concerns on Embodiment 1. FIG. FIG. 3 is a schematic vertical sectional view showing the vicinity of the shaft rear end portion of the shaft portion in the pressing device provided in the terminal connection portion according to the second embodiment. FIG. 2 is a schematic vertical sectional view showing the vicinity of the shaft rear end portion of the shaft portion, showing another example of the pressing device provided in the terminal connection portion according to the second embodiment. FIG. 3 is a front view of the pressing device provided in the terminal connection portion according to the third embodiment as viewed from the pressing flange portion side. It is a schematic vertical sectional view cut along the line (V)-(V) shown in FIG. It is a schematic vertical sectional view cut along the (VI)-(VI) line shown in FIG. It is a graph which shows the test body A in a test example. It is a graph which shows the test body B in a test example. It is a graph which shows the test body C in a test example.

[Explanation of Embodiment of the present invention]
When the terminal connection vibrates, the pressing device, which is one of the components, can also vibrate. Therefore, when it was investigated whether an abnormal sound was generated when the pressing device vibrated, it was found that the abnormal sound was generated in the vicinity of the elastic body which is the source of the pressing force. In particular, as shown in a test example described later, it was found that a loud abnormal noise is generated when the natural frequencies of the members constituting the pressing device including the elastic body overlap. Based on the above findings, the present invention defines a configuration that suppresses vibration of the pressing device. First, the contents of the embodiments of the present invention will be listed and described.

(1) The terminal connection portion according to the embodiment of the present invention is
The end of the cable in which the conductor and the cable insulator formed on the outer circumference of the conductor are gradually exposed, and the end of the cable.
A pre-molded insulator that is attached in close contact with the outer circumference of the cable insulator,
A bushing that houses the end of the cable and the premolded insulator,
A pressing device for pressing the premolded insulator from the rear end side to the tip side of the cable is provided.
The pressing device is
A cylindrical member arranged on the outer periphery of the cable insulator, which has a tip portion in contact with the premold insulator and a rear end portion located on the rear end side of the cable with respect to the tip portion. Department and
A plurality of shaft portions having one end fixed to the rear end portion and arranged in parallel with the axial direction of the cable, and a plurality of shaft portions.
A movable flange portion that is arranged on the other end side of the plurality of shaft portions and whose position along the plurality of shaft portions can be adjusted,
An elastic body that is attached to each of the shaft portions and urges the pressing portion to the tip end side of the cable with respect to the movable flange portion.
A vibration absorbing material arranged between each of the shaft portions and the elastic body is provided.

In the terminal connection portion, the elastic force of the elastic body can be adjusted by adjusting the position of the movable flange portion along the plurality of shaft portions. By urging the pressing portion to the tip end side of the cable with respect to the movable flange portion by this elastic force, the premold insulator can be pressed from the rear end side to the tip end side of the cable by the pressing portion. As a result, the premold insulator can be brought into close contact with both the bushing and the cable insulator, and a predetermined surface pressure can be applied to the interface between the premold insulator and the bushing and the interface between the premold insulator and the cable insulator. can.

In the pressing device, the terminal connection portion is provided with a vibration absorber between each shaft portion that easily vibrates and the elastic body, so that each shaft portion and the elastic body can be suppressed from vibrating, and the vibration is accompanied by vibration. It is possible to suppress the generation of abnormal noise.

(2) As an example of the terminal connection portion, the vibration absorber may be a tube made of resin or rubber.

Since the vibration absorber is a tube made of resin or rubber, it is easy to arrange the vibration absorber between each shaft portion and the elastic body. In addition, it is easy to suppress the vibration of each shaft portion and the elastic body.

(3) As an example of the terminal connection portion, further, an end side vibration absorbing material arranged between the shaft portion and the movable flange portion may be provided.

The movable flange portion has a displaceable gap along the plurality of shaft portions between the movable flange portion and each shaft portion. Therefore, when the shaft portion and the movable flange portion vibrate, they may come into contact with each other to generate an abnormal noise. By providing the end-side vibration absorber in this gap, it is easy to suppress the vibration of the movable flange portion and each shaft portion, and it is possible to suppress the generation of abnormal noise due to contact with each other. Among the members constituting the pressing device, the abnormal noise that may occur between the shaft portion and the elastic body can be suppressed, and the abnormal noise that may occur between the movable flange portion and the shaft portion can be suppressed, so that the pressing device can be suppressed. It is easier to suppress the generation of abnormal noise from the whole.

(4) As an example of the terminal connection portion, each shaft portion may be provided with a free end that is not fixed to the movable flange portion on the other end side, and a connecting plate that connects and fixes the free ends to each other. Can be mentioned.

If each shaft is at the free end, the shaft may vibrate on the free end side. By connecting and fixing the free ends to each other with a connecting plate, it is easier to suppress the vibration of the shaft portion. Since the vibration of the shaft portion can be suppressed, it is easy to suppress the generation of abnormal noise due to the contact between the shaft portion and other members, and it is easier to suppress the generation of abnormal noise from the entire pressing device.

(5) As an example of the terminal connection portion provided with the connecting plate, a part of the shaft portions of the plurality of shaft portions includes a male screw portion threaded at the free end, and the rest of the plurality of shaft portions. The shaft portion may include a tapered portion at the free end.

By providing a male screw portion at the free end of a part of the shaft portion and a tapered portion at the free end of the remaining shaft portion, it is easy to firmly fix the connecting plate to a plurality of shaft portions. This is because by fitting the bush into the gap formed between the tapered portion and the connecting plate, it is possible to suppress the movement of the connecting plate with respect to the plurality of shaft portions. By attaching a nut to the male thread portion, the connecting plate can be easily fixed to a plurality of shaft portions. Further, if the free end of the shaft portion is provided with a tapered portion, the shaft portion can be easily penetrated into the through hole formed in the movable flange portion or the connecting plate.

(6) As an example of the terminal connection portion, the pressing portion may include an annular recess for accommodating the end portion of the elastic body.

Since the elastic body is housed in the recess, it is easy to define the radial position of the elastic body with respect to the shaft portion. By defining the position of the elastic body, the distance between each shaft portion and the elastic body can be defined, it is easy to suppress the interference between each shaft portion and the elastic body, and the generation of abnormal noise from the pressing device is further suppressed. Easy to do.

[Details of Embodiments of the present invention]
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the drawings, the same reference numerals indicate the same names. It should be noted that the present invention is not limited to these examples, and is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

<Embodiment 1>
The terminal connection portion 1 according to the first embodiment will be described with reference to FIG. FIG. 1 shows a vertical cross section of the left half of the terminal connection portion 1 cut along a plane parallel to the axial direction of the power cable 100, and shows the appearance of the right half. Further, FIG. 1 also shows an enlarged view of the vicinity of the elastic body 44 in the pressing device 40 provided in the terminal connection portion 1. Here, the terminal connection portion 1 is an in-oil terminal connection portion for connecting the power cable 100 to a power device (not shown) such as a transformer.

≪Terminal connection part≫
〔Overview〕
The terminal connection portion 1 includes an end portion of the power cable 100 (hereinafter, cable end portion 10), a premold insulator 20, a bushing 30, and a pressing device 40. At the cable end 10, the conductor 11 of the power cable 100 and the cable insulator 12 are exposed stepwise. The premold insulator 20 is closely attached to the outer periphery of the cable insulator 12. The bushing 30 accommodates the cable end 10 and the premold insulator 20. The pressing device 40 presses the premold insulator 20 from the rear end side to the tip side of the power cable 100.

The pressing device 40 includes a pressing portion 41, a plurality of shaft portions 42, a movable flange portion 43, and an elastic body 44. The pressing portion 41 is arranged on the outer periphery of the cable insulator 12 and has a tip portion (pressing tip portion 411) that comes into contact with the premold insulator 20. The plurality of shaft portions 42 have one end (shaft tip portion 421) fixed to a rear end portion (pressing rear end portion 412) located on the rear end side of the power cable 100 in the pressing portion 41, and the power cable 100 has a plurality of shaft portions 42. Arranged parallel to the axial direction. The movable flange portion 43 is arranged on the other end side (shaft rear end portion 422 side) of the plurality of shaft portions 42, and the position along the plurality of shaft portions 42 can be adjusted. The elastic body 44 is attached to each shaft portion 42, and the pressing portion 41 is urged to the tip end side of the power cable 100 with respect to the movable flange portion 43. The pressing device 40 can adjust the elastic force of the elastic body 44 by displacing the position of the movable flange portion 43 toward the tip end side of the power cable 100 along the plurality of shaft portions 42. Then, by urging the pressing portion 41 to the tip end side of the power cable 100 by this elastic force, the premold insulator 20 can be pressed from the rear end side to the tip end side of the power cable 100 by the pressing portion 41.

One of the features of the terminal connection portion 1 of the first embodiment is that the pressing device 40 is provided with a vibration absorber 45 between each shaft portion 42 and the elastic body 44. Hereinafter, the configuration of the terminal connection portion 1 will be described in detail. In the following description, the tip side of the power cable 100 (the side where the conductor 11 is located in the state where the cable end 10 is housed in the bushing 30, the upper side of the paper surface in FIG. 1) is the tip side, and the opposite side (in FIG. 1). The lower side of the paper) is called the rear end side.

[Cable end]
The power cable 100 includes a conductor 11 and a cable insulator 12 formed on the outer periphery of the conductor 11, and is covered with a sheath 14. The power cable 100 in this example is a cross-linked polyethylene insulated vinyl sheath cable (CV cable). An internal semi-conductive layer (not shown) is provided on the inner peripheral portion of the cable insulator 12, and an outer semi-conductive layer 13 is provided on the outer peripheral portion. The end portion (cable end portion 10) of the power cable 100 is subjected to a step stripping process, and the conductor 11, the cable insulator 12, and the external semi-conductive layer 13 are exposed in this order from the tip end. A conductor drawer rod 90 is compressionally connected to the tip of the conductor 11.

[Premold insulator]
The premolded insulator 20 includes an insulating portion 21 and a semi-conductive portion 22 integrally molded with the insulating portion 21 on the rear end side of the insulating portion 21. The premold insulator 20 is a member that is closely attached to the outer periphery of the cable insulator 12 and relaxes the electric field at the end 10 of the cable in the bushing 30. The semi-conductive portion 22 of the premold insulator 20 is connected to the outer semi-conductive layer 13. The premold insulator 20 has a spindle shape that tapers from the central portion toward both ends, and a circular hole into which the cable insulator 12 is inserted is formed in the center thereof. In the premold insulator 20, the tapered surface (tip surface 23) located on the tip side is abutted against the contact surface 32 of the bushing 30 described later, and the tapered surface (rear end surface 24) located on the rear end side is described later. It is pressed by the pressing portion 41 of the pressing device 40. The premold insulator 20 is made of rubber such as ethylene propylene rubber or silicone rubber.

[Bushing]
The bushing 30 has an insertion opening 31 on the rear end side into which the cable end 10 is inserted, and houses the cable end 10 and the premold insulator 20 inside. The bushing 30 is a tubular member made of an insulating material, in this example an epoxy cannula. The inner diameter of the insertion opening 31 is larger than the outer diameter of the central portion of the premold insulator 20. The bushing 30 includes a tapered region in which the inner diameter decreases from the insertion opening 31 toward the tip side, and a uniform region in which the inner diameter becomes substantially uniform from the tapered region toward the tip side. The inner surface on the distal end side of the tapered region is a tapered contact surface 32 corresponding to the distal end surface 23 of the premold insulator 20. The premold insulator 20 is housed in the bushing 30 with the tip surface 23 abutting against the contact surface 32.

The bushing 30 is installed in a device case (not shown). A bushing flange portion 33 is provided in the insertion opening 31, and an adapter 50 for fixing to the bottom plate 200 of the equipment case is attached to the end surface of the bushing flange portion 33. An insulating cylinder 60 is attached to the adapter 50, and an intermediate flange portion 70 is attached to the rear end side of the insulating cylinder 60. The power cable 100 is immovable with respect to the bottom plate 200 of the equipment case. Therefore, the intermediate flange portion 70 is immovable with respect to the power cable 100 via the adapter 50 and the insulating cylinder 60. A shaft portion 433 for mounting the pressing device 40, which will be described later, is mounted on the intermediate flange portion 70. Since the intermediate flange portion 70 is immovable with respect to the power cable 100, the movable flange portion 43, which will be described later, moves in the longitudinal direction of the mounting shaft portion 433 with reference to the mounting shaft portion 433 attached to the intermediate flange portion 70. It is free. In addition, the intermediate flange portion 70 is attached with a cable protection metal fitting 80 that covers the vicinity of the end processing start of the cable end portion 10 (near the start position of the portion where the end treatment has been performed).

[Pressing device]
The pressing device 40 includes a pressing portion 41, a shaft portion 42, a movable flange portion 43, an elastic body 44, and a vibration absorbing material 45. The pressing device 40 urges the pressing portion 41 toward the tip side with respect to the movable flange portion 43 by the elastic force of the elastic body 44 arranged between the pressing portion 41 and the movable flange portion 43, and the pressing portion 41 thereof. Presses the premold insulator 20 toward the tip side. As a result, the premold insulator 20 is brought into close contact with both the bushing 30 and the cable insulator 12, and is predetermined at the interface between the premold insulator 20 and the bushing 30 and the interface between the premold insulator 20 and the cable insulator 12. Gives the surface pressure of.

(Pressing part)
The pressing portion 41 is a tubular member arranged on the outer periphery of the cable insulator 12 and is a member that directly presses the premold insulator 20. The pressing portion 41 includes a pressing tip portion 411 arranged on the front end side and a pressing rear end portion 412 arranged on the rear end side. The pressing front end portion 411 and the pressing rear end portion 412 may be composed of independent members or may be integrally formed of an integral body. In this example, the pressing tip portion 411 and the pressing rear end portion 412 are composed of independent members.

The pressing tip portion 411 comes into contact with the premold insulator 20. The inner surface on the tip end side of the pressing tip portion 411 is a pressing surface 413 having a shape corresponding to the rear end surface 24 of the premold insulator 20. The pressing tip portion 411 has an inner surface having a uniform inner diameter continuously from the pressing surface 413 toward the rear end side. The pressing tip portion 411 is a trumpet-shaped tubular member whose inner diameter increases toward the tip side.

The pressing rear end portion 412 is located on the rear end side of the pressing tip portion 411 and comes into contact with the end surface on the rear end side of the pressing tip portion 411. In this example, the pressing rear end portion 412 is a tubular member having an L-shaped cross section extending from the end surface on the rear end side of the pressing tip portion 411 to the inner surface. The pressing rear end portion 412 is integrally formed with a tubular vertical portion 412a extending in the axial direction of the power cable 100 and a vertical portion 412a, and has a flange shape extending in a direction intersecting (orthogonal) with the axial direction of the power cable 100. A lateral portion 412b is provided. The outer diameter of the lateral portion 412b is larger than the outer diameter of the end face on the rear end side of the pressing tip portion 411. A shaft portion 42, which will be described later, is fixed to the lateral portion 412b by screw coupling.

In this example, the lateral portion 412b of the pressing rear end portion 412 has an annular shape in which the end portion (elastic body tip portion 441) on the tip end side of the elastic body 44, which will be described later, is housed around each fixed shaft portion 42. It is provided with a recess 414. Since the elastic body tip portion 441 is housed in the recess 414, it is easy to define the position of the elastic body 44 with respect to each shaft portion 42. By defining the position of the elastic body 44, the distance between each shaft portion 42 and the elastic body 44 can be defined, and it is easy to suppress the interference between each shaft portion 42 and the elastic body 44. In particular, if the central axis of the recess 414 and the central axis of the shaft portion 42 are coaxial, the distance between each shaft portion 42 and the elastic body 44 tends to be uniform in the circumferential direction, and the distance between each shaft portion 42 and the elastic body portion 42 tends to be uniform. It is easier to suppress interference with 44.

In this example, the pressing tip portion 411 and the pressing rear end portion 412 are combined to form a cylindrical pressing portion 41 having a side wall continuous in the circumferential direction as a whole. In addition to this, the pressing tip portion 411 and the pressing rear end portion 412 are both annular members, and the pressing tip portion 411 and the pressing rear end portion 412 are connected by a plurality of rod-shaped members, and the pressing has a side wall intermittent in the circumferential direction. It can also be a department. The "cylindrical member" in the present invention also includes a pressing portion having a side wall intermittent in the circumferential direction.

(Shaft part)
Each shaft portion 42 has an end portion on the tip end side (shaft tip portion 421) threaded, and is fixed to the lateral portion 412b of the pressing rear end portion 412 by a screw connection. Each shaft portion 42 is arranged parallel to the axial direction of the power cable 100. A plurality of shaft portions 42 are provided at equal intervals (14 in this example) along the circumferential direction of the power cable 100 (see also FIG. 4). The end portion on the rear end side of each shaft portion 42 (shaft rear end portion 422) is not fixed to the movable flange portion 43 or the like, which will be described later, and is a free end. When the free end is tapered, each shaft portion 42 can easily penetrate through the through hole 431 of the movable flange portion 43 described later, and the pressing device 40 can be easily assembled. The free end of the shaft portion 42 will be described in detail in the third embodiment described later.

(Movable flange part)
The movable flange portion 43 is an annular member arranged on the rear end side (shaft rear end portion 422 side) of the plurality of shaft portions 42 and opposed to the lateral portion 412b of the pressing rear end portion 412. The movable flange portion 43 includes a plurality of through holes 431 through which the plurality of shaft portions 42 each penetrate. The diameter of each through hole 431 is slightly larger than the outer diameter of each shaft portion 42. Therefore, the movable flange portion 43 is movable along the plurality of shaft portions 42 in a state where each shaft portion 42 is penetrated through each through hole 431, and the position along the plurality of shaft portions 42 can be adjusted. be.

The outer diameter of the movable flange portion 43 is larger than the outer diameter of the lateral portion 412b of the pressing rear end portion 412. The movable flange portion 43 is provided with a plurality of (8 in this example) through holes 432 at equal intervals along the circumferential direction outward from the plurality of through holes 431 (see also FIG. 4). A mounting shaft portion 433 is passed through each through hole 432. Each mounting shaft portion 433 has a threaded end on the distal end side and is fixed to the intermediate flange portion 70 by screw coupling. Further, each mounting shaft portion 433 is also threaded at the rear end side end, and the nut 434 is coupled to the movable flange portion 43 in a state of being penetrated through each through hole 432 of the movable flange portion 43, and a plurality of movable flange portions 43 are provided. It is mounted on the mounting shaft portion 433. The diameter of each through hole 432 is larger than the outer diameter of each mounting shaft portion 433. Therefore, the movable flange portion 43 is movable along the plurality of mounting shaft portions 433 in a state where each mounting shaft portion 433 is penetrated through each through hole 432, and is movable along the plurality of mounting shaft portions 433. The position can be adjusted. The movable flange portion 43 is displaced to the front end side or the rear end side along a plurality of mounting shaft portions 433 as the nut 434 rotates, and the movable flange portion 43 is attached to the nut 434. Therefore, the position of the movable flange portion 43 on the rear end side of the mounting shaft portion 433 is fixed.

In this example, the movable flange portion 43 is provided with an annular recess 435 for accommodating the rear end portion (elastic body rear end portion 442) of the elastic body 44 described later around the through hole 431. By housing the elastic body rear end portion 442 in the recess 435, it is easy to define the position of the elastic body 44 with respect to each shaft portion 42. By defining the position of the elastic body 44, the distance between each shaft portion 42 and the elastic body 44 can be defined, and it is easy to suppress the interference between each shaft portion 42 and the elastic body 44. In particular, if the central axis of the recess 435 and the central axis of the shaft portion 42 are coaxial, the distance between each shaft portion 42 and the elastic body 44 tends to be uniform in the circumferential direction, and the distance between each shaft portion 42 and the elastic body portion 42 tends to be uniform. It is easier to suppress interference with 44. The elastic body tip portion 441 is housed in the recess 414 formed in the lateral portion 412b of the pressing rear end portion 412, and the elastic body rear end portion 442 is housed in the recess 435 formed in the movable flange portion 43. This makes it easier to define the distance between each shaft portion 42 and the elastic body 44. It is sufficient that at least one of the elastic body tip portion 441 and the elastic body rear end portion 442 is housed in the recesses 414 and 435, and only the elastic body tip portion 441 may be housed in the recess 414, or the elastic body. Only the rear end portion 442 may be housed in the recess 435.

(Elastic body)
The elastic body 44 is a coil-shaped spring mounted on the shaft portion 42. In this example, the elastic body 44 is a compression spring. In the elastic body 44, the elastic body tip portion 441 comes into contact with the pressing rear end portion 412, and the elastic body rear end portion 442 comes into contact with the movable flange portion 43. The elastic force of the elastic body 44 changes as the movable flange portion 43 is displaced along the plurality of shaft portions 42. The elastic body 44 urges the pressing portion 41 toward the tip side by the elastic force caused by the displacement of the movable flange portion 43 toward the tip side along the plurality of shaft portions 42. The elastic body 44 may be a combination of disc springs.

(Vibration absorber)
The vibration absorber 45 is a member that is arranged between each shaft portion 42 and the elastic body 44 and suppresses the interference between each shaft portion 42 and the elastic body 44. The vibration absorber 45 may be a tube made of resin or rubber. Examples of the resin constituting the vibration absorber 45 include polyvinyl chloride (PVC) and polyethylene (PE). In this example, the vibration absorber 45 is arranged over the entire region of the shaft portion 42 covered by the elastic body 44.

The thickness of the vibration absorber 45 may be 0.05 mm or more and 0.5 mm or less, although it depends on the distance between each shaft portion 42 and the elastic body 44. When the thickness of the vibration absorber 45 is 0.05 mm or more, it is easy to suppress the vibration of each of the shaft portion 42 and the elastic body 44. On the other hand, when the thickness of the vibration absorber 45 is 0.5 mm or less, it is possible to suppress the increase in size of the vibration absorber 45 and the increase in size of the elastic body 44. The thickness of the vibration absorber 45 may be further 0.1 mm or more and 0.5 mm or less.

≪Assembly method of terminal connection part≫
An example of the assembly method of the terminal connection portion 1 according to the above-described first embodiment will be described.

First, the end of the power cable 100 is stepped off to gradually expose the conductor 11, the cable insulator 12, and the external semi-conductive layer 13. The conductor drawer rod 90 is fitted from the outer periphery of the exposed conductor 11 and compressed to connect the conductor 11 and the conductor drawer rod 90. The premold insulator 20 is attached to the outer periphery of the cable insulator 12. The premolded insulator 20 is attached to the cable insulator 12 after the cable end portion 10 is passed through the central holes of the movable flange portion 43 and the pressing portion 41 of the pressing device 40.

The cable end 10 is inserted through the insertion opening 31 of the bushing 30 and accommodated in the bushing 30. The cable end 10 is inserted into the bushing 30 until the tip surface 23 of the premold insulator 20 is pressed against the contact surface 32 of the bushing 30.

The pressing device 40 is attached. First, the shaft portion 42 is screw-coupled to the pressing rear end portion 412, and the mounting shaft portion 433 is screw-coupled to the intermediate flange portion 70. Next, the elastic body 44 is attached to each shaft portion 42. At this time, the elastic body tip portion 441 is housed in the recess 414 formed in the pressing rear end portion 412. After that, the shaft portion 42 is passed through each through hole 431 of the movable flange portion 43, the mounting shaft portion 433 is passed through each through hole 432, and the nut 434 is connected to the end portion of the mounting shaft portion 433. At this time, the nut 434 is coupled so as to push the movable flange portion 43 toward the tip side against the elastic force of the elastic body 44. By doing so, the pressing portion 41 can be urged toward the tip side with respect to the movable flange portion 43 by the elastic force of the elastic body 44. As a result, the pressing surface 413 of the pressing tip portion 411 presses the rear end surface 24 of the premold insulator 20 toward the tip side, and the tip surface 23 of the premold insulator 20 presses the contact surface 32 of the bushing 30 toward the tip side. ..

≪Effect≫
The terminal connection portion 1 according to the first embodiment shifts the position of the movable flange portion 43 toward the tip side along the plurality of shaft portions 42 to adjust the elastic force of the elastic body 44, and the pressing portion 41 is pressed by this elastic force. By urging the tip side, the premold insulator 20 can be pressed toward the tip side by the pressing portion 41. As a result, the premold insulator 20 can be brought into close contact with both the bushing 30 and the cable insulator 12, and is predetermined at the interface between the premold insulator 20 and the bushing 30 and the interface between the premold insulator 20 and the cable insulator 12. Surface pressure can be applied.

In the pressing device 40, the terminal connection portion 1 is provided with a vibration absorbing material 45 between the shaft portion 42 and the elastic body 44, which are easily vibrated, so that the shaft portion 42 and the elastic body 44 vibrate respectively. Can be suppressed, and the generation of abnormal noise due to vibration can be suppressed. By suppressing the abnormal sound that may be generated from the pressing device 40, it is possible to suppress the generation of the abnormal sound in the entire terminal connection portion 1 in the first place. Even if an abnormal sound is generated in the terminal connection portion 1 due to a cause other than the pressing device 40 due to a partial discharge or the like, the pressing device 40 can be excluded as the cause of the abnormal sound, so that the cause of the abnormal sound can be easily identified. ..

<Embodiment 2>
The terminal connection portion according to the second embodiment will be described with reference to FIGS. 2 and 3. In FIGS. 2 and 3, configurations having the same functions as those in the first embodiment are designated by the same reference numerals as those in the first embodiment. Hereinafter, in the present embodiment, the differences from the first embodiment will be mainly described.

In addition to the configuration of the terminal connection portion 1 according to the first embodiment, the terminal connection portion according to the second embodiment further absorbs vibration on the end side arranged between at least one shaft portion 42 and the movable flange portion 43. One of the features is that the material 46 is provided. In the case of the terminal connection portion 1 according to the first embodiment, the movable flange portion 43 has a displaceable gap along the plurality of shaft portions 42 between each shaft portion 42 and the movable flange portion 43. The end-side vibration absorber 46 is a member that suppresses the shaft portion 42 and the movable flange portion 43 from interfering with each other by being arranged in the gap. The end side vibration absorber 46 may be a tube made of resin or rubber. Examples of the resin constituting the end-side vibration absorber 46 include PVC and PE, as in the vibration absorber 45.

The shaft portion 42 includes a shaft main body portion 422a and a male screw portion 422b formed on the shaft rear end portion 422. As shown in FIG. 2, the end side vibration absorber 46 can be continuously provided between the end surface on the rear end side of the vibration absorber 45 and the nut 423 coupled to the male thread portion 422b. That is, the end-side vibration absorbing material 46 can be continuously provided on the vibration absorbing material 45 by extending to the shaft rear end portion 422 of the shaft portion 42. By arranging the end side vibration absorber 46 continuously up to the shaft rear end portion 422 on the vibration absorber 45, it is movable with the shaft portion 42 regardless of the position of the movable flange portion 43 along the shaft portion 42. An end-side vibration absorber 46 can be interposed between the flange portion 43 and the flange portion 43. In this case, the end-side vibration absorber 46 may be composed of an integral body integrally molded with the vibration absorber 45, or may be composed of a member independent of the vibration absorber 45. When the vibration absorber 45 and the end side vibration absorber 46 are separate members, they may be made of the same material or may be made of different materials.

The shaft portion 42 can be provided with a region having a smaller outer diameter than the others on the male screw portion 422b side of the shaft main body portion 422a (not shown). In this case, the shaft main body portion 422a has a step between a region having a large outer diameter and a region having a small outer diameter. The end-side vibration absorber 46 can be provided between this step and the nut 423 coupled to the male threaded portion 422b. When the end-side vibration absorber 46 is pressed against the step formed in the shaft body portion 422a, the end-side vibration absorber 46 is interposed between the shaft portion 42 and the movable flange portion 43 as much as possible. However, it does not have to be provided up to the end face on the rear end side of the vibration absorber 45. This is because even if the position of the movable flange portion 43 is displaced along the shaft portion 42, the end side vibration absorber 46 is fixed by a step, so that the position shift is unlikely to occur.

The shaft portion 42 has a step between the male screw portion 422b and the shaft main body portion 422a when the outer diameter of the male screw portion 422b is smaller than the outer diameter of the shaft main body portion 422a. As shown in FIG. 3, the end-side vibration absorber 46 can include a hooking portion 461 that is hooked on this step. When the end-side vibration absorber 46 is provided with a hook portion 461, the end-side vibration absorber 46 may be interposed between the shaft portion 42 and the movable flange portion 43 as much as possible, and the vibration absorber 45 may be provided with a hook portion 461. It does not have to be provided up to the end face on the rear end side. This is because even if the position of the movable flange portion 43 is displaced along the shaft portion 42, the end side vibration absorber 46 is fixed by the hook portion 461, so that the position shift is unlikely to occur.

By providing the end side vibration absorbing material 46 in the gap formed between each shaft portion 42 and the movable flange portion 43, it is easy to suppress the vibration of each shaft portion 42 and the movable flange portion 43, respectively. It is possible to suppress the generation of abnormal noise due to contact with each other. Among the members constituting the pressing device 40, the abnormal noise that may occur between the shaft portion 42 and the elastic body 44 can be suppressed, and the abnormal noise that may occur between the shaft portion 42 and the movable flange portion 43 can be suppressed. By being able to do so, it is easier to suppress the generation of abnormal noise from the entire pressing device 40.

<Embodiment 3>
The terminal connection portion according to the third embodiment will be described with reference to FIGS. 4 to 6. In FIGS. 4 to 6, the configurations having the same functions as those in the first embodiment are designated by the same reference numerals as those in the first embodiment. Hereinafter, in the present embodiment, the differences from the first embodiment will be mainly described.

One of the features of the terminal connection portion according to the third embodiment is that, in addition to the configuration of the terminal connection portion 1 according to the first embodiment, a connecting plate 47 is further provided. In the case of the terminal connection portion 1 according to the first embodiment, each shaft portion 42 includes a free end that is not fixed to the movable flange portion 43 at the rear end side end portion (shaft rear end portion 422). The connecting plate 47 is an annular member that connects the free ends of the shaft portions 42 to each other.

Here, a part of the shaft portions 42 among the plurality of shaft portions 42 includes a male screw portion 422b (FIG. 5) threaded at the free end, and the remaining shaft portion 42 of the plurality of shaft portions 42 has a free end. Is provided with a tapered portion 422c (FIG. 6). In this example, the shaft portion 42 provided with the male screw portion 422b has an outer diameter of the male screw portion 422b smaller than the outer diameter of the shaft main body portion, and has a step between the male screw portion 422b and the shaft main body portion.

As shown in FIGS. 4 to 6, the connecting plate 47 is smaller than the outer diameter of the movable flange portion 43, and is arranged on the rear end side of the movable flange portion 43 as shown in FIGS. 5 and 6. The connecting plate 47 includes a plurality of through holes 471 through which the plurality of shaft portions 42 each penetrate. The diameter of each through hole 471 is equal to or slightly larger than the outer diameter of the male screw portion 422b, and is smaller than the outer diameter of the shaft main body portion. Therefore, as shown in FIG. 5, the connecting plate 47 is pressed against the step formed by the shaft main body portion and the male screw portion 422b in a state where each shaft portion 42 is penetrated through each through hole 471. Then, the connecting plate 47 is fixed by being sandwiched between the step and the nut 423 by connecting the nut 423 to the male threaded portion 422b in a state where each shaft portion 42 is penetrated through each through hole 471.

As shown in FIG. 6, the shaft portion 42 including the tapered portion 422c has a gap between the tapered portion 422c and the connecting plate 47. This gap is filled by the bush 48. The bush 48 includes a bush main body 481 interposed between the tapered portion 422c and the connecting plate 47, and a bush flange portion 482 extending in a direction parallel to the surface of the connecting plate 47 from the distal end of the bush main body 481. To prepare for. The outer diameter of the bush main body 481 is the same as the diameter of the through hole 471 of the connecting plate 47, and the inner diameter corresponds to the tapered portion 422c. The outer diameter of the bush flange portion 482 is larger than the diameter of the through hole 471 of the connecting plate 47, and the inner diameter corresponds to the tapered portion 422c. Therefore, when the tapered portion 422c to which the bush 48 is mounted is passed through the through hole 471 of the connecting plate 47, the connecting plate 47 is abutted against the bush flange portion 482 and the gap between the tapered portion 422c is filled. Be done.

When the shaft rear end portion 422 of each shaft portion 42 is a free end, by providing the connecting plate 47, it is possible to suppress the vibration of each shaft portion 42 at the free end, and the shaft portion 42 and the movable flange portion 43 can be separated from each other. It is possible to suppress the generation of abnormal noise due to contact with each other. Among the members constituting the pressing device 40, the abnormal noise that may occur between the shaft portion 42 and the elastic body 44 can be suppressed, and the abnormal noise that may occur between the shaft portion 42 and the movable flange portion 43 can be suppressed. By being able to do so, it is easier to suppress the generation of abnormal noise from the entire pressing device 40. Further, by providing the end side vibration absorbing material 46 between the shaft portion 42 and the movable flange portion 43, it is easier to suppress the generation of abnormal noise from the entire pressing device 40.

[Test example]
A pressing device having a configuration for suppressing vibration was manufactured, and the presence or absence of abnormal noise was investigated. In this example, each test body simulating a pressing device was attached to a vibration tester, and the relationship between the natural frequency of each member constituting the pressing device and the generation of abnormal noise was investigated.

[Test body A]
As the test body A, a pressing rear end portion, a shaft portion, a movable flange portion, an elastic body, and a vibration absorber were prepared among the pressing portions. One end side of the shaft portion was fixed to the rear end portion of the pressing, an elastic body was attached to the outer periphery of the shaft portion, and a vibration absorber was placed between the shaft portion and the elastic body portion. The gap between the shaft portion and the elastic body was about 0.5 mm, and the thickness of the vibration absorber was 0.1 mm. A movable flange portion whose position along a plurality of shaft portions can be adjusted is mounted on the other end side of each shaft portion (see FIG. 1).

[Test body B]
As the test body B, a pressing rear end portion, a shaft portion, a movable flange portion, an elastic body, and a connecting plate were prepared among the pressing portions. One end side of the shaft portion was fixed to the rear end portion of the pressing, and an elastic body was attached to the outer circumference of the shaft portion. A movable flange portion whose position along a plurality of shaft portions can be adjusted is mounted on the other end side of each shaft portion. Further, the free ends on the other end side of the shaft portion were connected to each other by a connecting plate and fixed. Since a part of the free end is a male screw part and the rest is a tapered part, the connecting plate is fixed by using a nut and a bush (see FIGS. 5 and 6). The test body B has no interposition between the shaft portion and the elastic body, and has a gap of about 0.5 mm.

[Test body C]
As a comparative example, a test body C having no configuration for suppressing vibration was produced. The test body C is the same as the test body A except that the test body C is not provided with the vibration absorber.

〔Test condition〕
Each test piece was placed on a vibration tester so that the rear end of the press was facing down. Then, the movable flange portion was displaced toward the pressing rear end portion to adjust the elastic force of the elastic body, and the pressing rear end portion was urged by this elastic force. In the vibration tester, in order to generate radial (lateral) vibration of the pressing part and the movable flange part, the acceleration is set to 1.0 m / s ² , the frequency is gradually increased from 5 Hz to 1000 Hz, and the elasticity is increased. The resonance peaks of the body, shaft, and movable flange were searched, and the presence or absence of abnormal noise was confirmed by human judgment. The result of the test body A is shown in FIG. 7, the result of the test body B is shown in FIG. 8, and the result of the test body C is shown in FIG. In each figure, the vertical axis is acceleration and the horizontal axis is frequency. Further, in each figure, the long dotted line indicates the elastic body, the short dotted line indicates the shaft portion, and the solid line indicates the movable flange portion.

No abnormal noise was observed in the test body A in which the vibration absorber was interposed between the shaft portion and the elastic body. Looking at FIG. 7, it can be seen that in the test body A, the natural frequencies of the members do not overlap. That is, it is considered that the test body A was able to suppress the vibration of each member. On the other hand, although there is a gap between the shaft portion and the elastic body, the test body B in which the free ends of the shaft portion are connected by a connecting plate generated a small abnormal sound. Looking at FIG. 8, it can be seen that in the test body B, the natural frequencies of the respective members overlap (see the circled portion). Further, the test body C having a gap between the shaft portion and the elastic body and having the free end of the shaft portion as it is generated an abnormal noise louder than that of the test body B. Looking at FIG. 9, it can be seen that in the test body C, the natural frequencies of the respective members overlap (see the circled portion). Here, when FIG. 8 and FIG. 9 are compared, it can be seen that the peak of the portion where the natural frequencies of the members overlap is smaller in FIG. 8 than in FIG. From this, it is considered that the vibration suppression effect is more effective when the free ends of the shaft portions are connected to each other than when they are in the same state. For example, the shaft may vibrate on the free end side depending on the gap between the shaft and the elastic body, the thickness of the vibration absorber, etc., but by connecting the free ends to each other, the vibration of the shaft can be generated. It is thought that it can be suppressed.

Further, the following appendices will be disclosed in relation to the embodiments of the present invention described above.

[Additional Notes]
In addition, the terminal connection portion according to the embodiment is
The end of the cable in which the conductor and the cable insulator formed on the outer circumference of the conductor are gradually exposed, and the end of the cable.
A pre-molded insulator that is attached in close contact with the outer circumference of the cable insulator,
A bushing that houses the end of the cable and the premolded insulator,
A pressing device for pressing the premolded insulator from the rear end side to the tip side of the cable is provided.
The pressing device is
A cylindrical member arranged on the outer periphery of the cable insulator, which has a tip portion in contact with the premold insulator and a rear end portion located on the rear end side of the cable with respect to the tip portion. Department and
A plurality of shaft portions having one end fixed to the rear end portion and arranged in parallel with the axial direction of the cable, and a plurality of shaft portions.
A movable flange portion that is arranged on the other end side of the plurality of shaft portions and whose position along the plurality of shaft portions can be adjusted,
An elastic body that is attached to each of the shaft portions and urges the pressing portion to the tip end side of the cable with respect to the movable flange portion.
It is possible to include a connecting plate for connecting and fixing free ends that are not fixed to the movable flange portion on the other end side of the shaft portion.

If each shaft is at the free end, the shaft may vibrate on the free end side. According to the terminal connection part in the above appendix, by connecting and fixing the free ends to each other with a connecting plate, the vibration of the shaft part can be suppressed, and an abnormality occurs due to the contact between the shaft part and other members. It is possible to suppress the generation of sound.

1 Termination connection 100 Power cable 10 Cable end 11 Conductor 12 Cable insulator 13 External semi-conductive layer 14 Sheath 20 Premold insulator 21 Insulation 22 Semi-conductive part 23 Front end surface 24 Rear end surface 30 Bushing 31 Insertion opening 32 Surface 33 Bushing flange 40 Pressing device 41 Pressing part 411 Pressing tip part 412 Pressing rear end part 412a Vertical part 412b Horizontal part 413 Pressing surface 414 Recession 42 Shaft part 421 Shaft tip part 422 Shaft rear end part 422a Shaft body part 422b Male thread part 422c Tapered part 423 Nut 43 Movable flange part 431, 432 Through hole 433 Mounting shaft part 434 Nut 435 Recessed part 44 Elastic body 441 Elastic body tip 442 Elastic body rear end 45 Vibration absorber 46 End side vibration absorber 461 Hook Part 47 Connection plate 471 Through hole 48 Bush 481 Bush body part 482 Bush flange part 50 Adapter 60 Insulation cylinder 70 Intermediate flange part 80 Cable protection bracket 90 Conductor drawer bar 200 Bottom plate of equipment case

Claims (5)

The end of the cable in which the conductor and the cable insulator formed on the outer circumference of the conductor are gradually exposed, and the end of the cable.
A pre-molded insulator that is attached in close contact with the outer circumference of the cable insulator,
A bushing that houses the end of the cable and the premolded insulator,
A pressing device for pressing the premolded insulator from the rear end side to the tip side of the cable is provided.
The pressing device is
A cylindrical member arranged on the outer periphery of the cable insulator, which has a tip portion in contact with the premold insulator and a rear end portion located on the rear end side of the cable with respect to the tip portion. Department and
A plurality of shaft portions having one end fixed to the rear end portion and arranged in parallel with the axial direction of the cable, and a plurality of shaft portions.
A movable flange portion that is arranged on the other end side of the plurality of shaft portions and whose position along the plurality of shaft portions can be adjusted,
An elastic body that is attached to each of the shaft portions and urges the pressing portion to the tip end side of the cable with respect to the movable flange portion.
A vibration absorber arranged between each of the shaft portions and the elastic body is provided .
Each shaft portion is provided with a free end that is not fixed to the movable flange portion on the other end side.
A connecting plate for connecting and fixing the free ends to each other is provided.
Termination connection. Some of the plurality of shafts have a male threaded portion threaded at the free end.
The terminal connection portion according to claim 1 , wherein the remaining shaft portion of the plurality of shaft portions is provided with a tapered portion at the free end. The terminal connection portion according to claim 1 or 2 , wherein the vibration absorber is a tube made of resin or rubber. The terminal connection portion according to any one of claims 1 to 3, further comprising an end-side vibration absorber arranged between at least one shaft portion and the movable flange portion. The terminal connection portion according to any one of claims 1 to 4 , wherein the pressing portion includes an annular recess for accommodating an end portion of the elastic body.

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