JPS5939969B2 - electrical cable accessories - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the attachment of electrical cable accessories, such as terminal fittings and electrical connection elements, to electrical cables in electrical distribution systems, and in particular to the attachment of such accessories to electrical cables as previously practiced. The present invention relates to electrical cable accessories that are shaped to be easier to install than other electrical cable accessories.

In recent years, there has been a strong demand for the development of underground power distribution systems, especially in light industrial areas, commercial areas, and residential areas.

Various types of power distribution equipment have been developed for use in such systems, such as power cables, transformers, and cable accessories such as terminal equipment and electrical connection equipment.

Cable accessories such as terminal fittings and electrical connection fittings in these devices have been developed to be installed in the field at the ends of electrical cables to facilitate construction and installation of underground distribution systems. .

In most cases, these cable fittings or devices are placed on the end of the cable, or the components of the fitting are used to create a clamp between a member of elastomeric resilient material and the cylindrical surface on which the member rests. The attachment is mated and can be installed.

This proper tightening will create a clamping force between the mating elements suitable for the mating to obtain and maintain both the mechanical and electrical integrity of the assembly.

A lubricant is used to reduce the frictional forces encountered during installation and to facilitate proper installation of the cable accessory to Cable-L.

Typically, lubricant is applied to the surface of the cable and also to the inside of the opening in the cable accessory before the cable is inserted into the opening.

However, the shape of the accessory aperture causes a large portion of the lubricant to be wiped off the cable surface when the cable is inserted into the aperture, greatly reducing the lubricant's ability to facilitate insertion.

It is therefore an object of the present invention to provide an electrical cable accessory having a configuration that facilitates lubricated installation of the cable accessory.

Another object of the invention is to have an opening for receiving the cable and an entrance passageway in the enlarged inner surface into which the cable is inserted;
The shape of the inlet passage is such that it facilitates the installation of electrical cable accessories, such as terminal devices or electrical connection elements, into which lubricant enters the opening.

Yet another object of the invention is to provide an electrical cable attachment having an enlarged inner surface entry passageway as described above and ensuring that the cable is properly tightened within the opening of the attachment quantity once the installation is completed. It is about providing quantity.

Yet another object of the present invention is to have an enlarged inner surface entrance passageway as described above, which is capable of receiving an electrical cable having an outer diameter within a predetermined diameter range, and which facilitates its installation. The object of the present invention is to provide an electrical cable attachment that ensures a proper assembly relationship between the cable and the attachment.

Yet another object of the invention is to provide for the manufacture of electrical cable appendages that can be attached or assembled to relatively large sized electrical cables in the field by using lubricants to facilitate assembly or attachment. The goal is to put it into practical use.

Still another object of the invention is, without departing from the annexes of the same type currently employed, to
It is an object of the present invention to provide an electrical cable appendage having a structure embodying a shape that facilitates the attachment or assembly of the appendage to the cable, particularly in the field using lubricants.

The various objects and advantages mentioned above are achieved by the present invention,
The outline is as follows.

In other words, for an attached quantity of an electric cable that is attached to the end of an electric cable consisting of a conductor, an insulator around it, and a conductive shield around it using a lubricant to facilitate installation, the attached quantity is , having an open end through which the cable end through which the insulator is exposed is inserted, and an axially extending opening for receiving the cable end, into which the insulator is firmly attached. a sleeve-like member of elastomeric resilient material having an elastically expandable insulator clamping portion for tightening and an inlet passageway extending between the insulator clamping portion and an open end; The passageway extends radially outward from the insulator clamping portion toward the open end, and the inside diameter of the inlet passageway at the open end is substantially larger than the outside diameter of said cable with exposed insulation. The inlet passage includes a first tapered portion that is tapered from the maximum diameter at the open end to a first predetermined diameter at a distance in the axial direction from the open end; There is a part of the second taper that is tapered from the first predetermined diameter to the second predetermined diameter that contacts the insulator tightening part of the opening. The first predetermined diameter and the second predetermined diameter are large enough to allow lubricant on the cable to enter the opening, and the first predetermined diameter and the second predetermined diameter are a portion of the second taper of the inlet passage and a predetermined range of outer diameter of the cable. The related dimensions are such that it is possible to ensure that the cable is firmly clamped at a position along the second tapered portion of the inlet passage.

The present invention will be better understood, and various objects and advantages thereof will become apparent from the following detailed description of the embodiments illustrated in the accompanying drawings.

Figure 1 is a longitudinal cross-sectional view of an electric cable terminal device in which the electric cable attachment amount of the present invention is applied to the electric cable terminal device, and is a front view and a longitudinal cross-section of the electric cable and other parts necessary to construct the cable terminal portion. Both the figure and the partially cutaway front view are shown.

FIG. 2 is a partially cutaway front view showing the structure of the terminal portion of an electric cable constructed using the terminal device of the present invention shown in FIG.

Fig. 3 is a vertical sectional view of a connector elbow of an electric cable when the electric cable attachment of the present invention is applied to the connector elbow of the electric cable, and the electric cable and other parts necessary for assembling it at the end of the cable are partially cut. A front view and a front view are shown.

FIG. 4 is a partially cutaway front view showing the structure of the terminal portion of an electric cable constructed using the connector elbow of the present invention shown in FIG. 3.

Referring now to the drawings, and in particular to FIGS. 1 and 2, electrical cable 10 has a central conductor 12 surrounded by an insulator 14, which insulator 14 is surrounded by a conductive shield 16. As shown in FIG.

The outer surface 18 of the cable 10 has an outer diameter within a predetermined minimum and maximum diameter range, such that a particular cable appendage constructed in accordance with the present invention is compatible with this range of variation in cable outer diameter. ing.

A cable attachment in the form of a terminal device 20 constructed in accordance with the invention is adapted to be attached to the end of a cable 10, the cable 10 having a length of the shield 16 stripped off for its attachment. The insulator 14 is exposed beyond the end 22 of the shield 16, and the insulator 14 is further exposed.
The conductor 12 is exposed beyond the end 24 of the insulator 14 by stripping off a certain length.

Note that 26 is the exposed end of the conductor 12.

Terminal device 20 includes a first electrically conductive elastomeric elastic material.
It consists of a sleeve-like member 28 in the form of a nozzle of elastomeric elastic material of composite construction having a section 30 and a second section 32 of insulating elastomeric elastic material integrally molded with this first section 30. ing.

The shape of the boundary 34 between the first and second portions 30 and 32 is
It constitutes an electrical stress relieving section when the cable 10 is terminal-processed.

The plurality of annular folds 36 increase the creepage distance of the insulation of the sleeve-like member 28.

The sleeve-like member 28 has an opening 40 in the form of a central bore extending axially through the length of the sleeve-like member for receiving the end of the cable 10.

Attachment is accomplished by inserting the end of the cable 10 into the opening 40 of the sleeve-like member 28 in the direction of the arrow 42 in FIG.
As shown, the cable 10 is inserted into the sleeve 28 until the sleeve 28 is properly positioned over the cable end.
This is done by inserting it into 8.

When the sleeve-like member 28 is so positioned on the cable 10, the annular washer 44 is slid over the conductor 12 and rests on the end face of the end 24 of the insulator 14.

The washer 44 extends radially outside the opening 40 along the upper end 46 of the sleeve-like member 28.

Next, the terminal connector 50 is placed over the exposed portion of the conductor 120 and fixed at 52 by, for example, crimping.

This terminal connector is a universal rod connector 5 that projects upwards for connection within the power distribution system.
4.

The annular washer 44 is thus held there, and the cable 10 is secured against slippage from the sleeve-like member 28.

A required number of spacers 48 are inserted between the washer 44 and the terminal connector 50 to prevent the cable 10 from shifting.

Molded elastomeric resilient material cap 56
is placed over the top end 46 and over the terminal connector 50 and is tightly fitted to provide water tightness.

The grounding strap 58 is then secured to the conductive first portion 30 of the sleeve-like member 28 to complete the installation.

The relative dimensions of the aperture 40 and the cable 10 are such that each part of the aperture is elastically expanded to clamp a corresponding part of the cable, with sufficient clamping force to provide a watertight, insulative seal as required, and as required. The electrical connection and the desired mechanical tightness can be achieved accordingly.

Thus, at least the opening 400 portions of the insulator clamping portions 60 and 62 have an inner diameter somewhat smaller than the outer diameter of the insulator 14, and the insulating second portion of the sleeve-like member 28 has an inner diameter slightly smaller than the outer diameter of the insulator 14. Insulator fastenings 60 and 6 along the majority
2 are elastically expanded and tightened around the insulator 14 to ensure watertightness and increase the dielectric strength of the creepage path along the outer surface of the insulator 14 between the top end 46 and the end 22 of the shield 16. This provides a strong mechanical connection between the sleeve-like member 28 and the cable 10.

Another portion 64 of the aperture 40 is connected to the sleeve-like member 28.
conductive first portion 30 of the cable shield 16 .
has an inner diameter slightly smaller than the outer diameter of the shield 16 , and the portion 64 is elastically expanded to tighten the shield 16 .
and the first portion of the sleeve-like member 28 is provided.

Cable 10V? - To facilitate the installation of the sleeve-like member 28, a lubricant 65, for example silicone grease, is applied along the outer surface of the cable 10, in particular the outer surface of the exposed part of the insulation 14, and inside the opening 40. This makes it easy to insert the ＼ cable.

Lubricant is also applied within the opening 40 of the sleeve-like member.

Although such methods have been used in the past, they tend to wipe lubricant from the cable at the entrance of the aperture, thereby reducing the amount of available lubricant along the aperture and concomitantly reducing the amount of lubricant available along the aperture. Its effectiveness is hampered by increased frictional forces that tend to prevent complete assembly from being accomplished.

The sleeve-like member 28 is installed to alleviate the problem of lubricant 65 being wiped off the surface of the cable 100.
The aperture 40 is provided with an inlet passage 66 leading to a lower open end 68 thereof, the inlet passage 66 having a mounting radially outwardly so as to allow lubricant 65 on the cable to enter the aperture 40. It has an expanding shape.

An inlet passageway 66 extends radially outwardly from the insulator clamping portion 62 of the aperture 40 toward an open end 68 and generally includes a first tapered portion 70 and a first tapered portion 64 corresponding to the inlet passageway portion 64. 2 taper part γ2.

The first tapered portion 70 is spaced axially from the open end 68 from the maximum diameter at the open end 68 to a first predetermined diameter D.
It has a taper that narrows in the first ma, and the second
The tapered portion 72 extends from the first predetermined diameter D0 to the insulator tightening portion 62.
It is tapered to be narrowed at the second predetermined diameter D2 which is in contact with the second predetermined diameter D2.

The taper of the first tapered portion 70 is steeper than the taper of the second tapered portion 72, as shown in FIG. It is designed to be effective.

Since the maximum diameter of the open end 68 is sufficiently larger than the largest outer diameter of the cable 10, the cable 10
It is not a scale that can be inserted, but it also allows the lubricant on the cable to be inserted, with the least amount of lubricant being wiped off.

The relatively steep taper of the first tapered portion 70 facilitates passage of lubricant toward the second tapered portion 72 while the inner diameter of the inlet passageway 66 is reduced to the first predetermined diameter D1.

That is, when the cable 10 is inserted into the entrance passage 66,
The outer edge of the end portion 24 of the insulator 14 is a first tapered portion 70.
The lubricant on the inner surface of the first tapered portion 70 behind the contact point is wiped off considerably by the contact, but the lubricant on the insulator 14 is removed from the surface of the insulator 140 and the inner surface of the first tapered portion 70. Since the contact angle of the first taper portion 70 with the tapered surface is small, not much lubricant is wiped off, and some of the lubricant that is wiped off is created by the insulator 14 and the first taper portion 70. Although it accumulates in an acute-angled space, it is difficult to escape backwards, and the cable 10
The lubricant on the surface of the insulator 140 is eventually sent to the second tapered portion 72 without being wiped off.

Cable 1 with the smallest outer diameter for both predetermined diameters D1 and D20
The second predetermined diameter D2 is preferably equal to the inner diameter of the insulator fastening portion 62 of the opening 40.

The relationship between the second tapered portion 72 and the cable 10 having a diameter within a predetermined range is such that the second tapered portion 72 elastically expands to tighten the shield 16 and the shield 16 and the housing 28 This ensures that a proper electrical connection is made with the first portion 30.

The axial distance between the predetermined diameters D□ and D2 is such that the end portion 22 of the shield 16 can be positioned anywhere within the axial section defined by the axial distance between the predetermined diameters D1 and D20. The first portion 30 of the sleeve-like member 28 and the shield 160 are selected to provide a suitable tight clamping between the sleeve-like member 28 and the shield 160.

Thus, the gentle taper of the second portion 72 of the inlet passageway 66 accommodates any variations in the position of the end 22 of the shield 16 due to the end 24 of the insulator 14 and the end 26 of the conductor 12. It acts to compensate.

At the same time, the gentle taper of the second tapered portion 72 of the inlet end 66 reduces the gap 74 formed between the first portion 30 of the sleeve-like member 28 and the insulator 14 at the end 22 of the shield 16. It helps reduce the size and
Some tolerance is allowed for the axial position of the end 22 of the shield 16 relative to the sleeve-like member 28.

As mentioned above, the second predetermined diameter D2 is preferably equal to the inner diameter of the insulator fastening portion 62 of the opening 40.

The second tapered portion 72 is connected to the first portion 3 of the sleeve-like member 28.
0, and the second predetermined diameter D2 is axially spaced from the boundary 34 in the direction of the open end 68;
An insulator clamp 62 extends into the first portion 30.

Thus, the gap 74 will be surrounded by the conductive material of the first portion 30.

Furthermore, the boundary 34 will be located where there is no gap between the sleeve-like member 28 and the cable insulation 14.

Preferably, the steeper taper of the first tapered portion 70 and the gentler taper of the second tapered portion 72 of the inlet passageway 66 are expanded shapes that follow an exponential plane.

However, the exponential function surface may be approximated by a surface connecting various conical surfaces.

Thus, it is preferable that the expanded shape of the surface of the inlet passage 660 is at least a shape that approximates an exponential function surface.

The aperture 40 has two axially spaced insulator clamps 60 and 62 and another hole portion 76 located therebetween.

The IJ IJ-flange 76 has an inner diameter larger than the inner diameter of the insulator clamps 60 and 62, and is preferably larger than the diameter of the insulator 14, and is mounted therein to reduce frictional forces along the insulator 14. IJ Acts as an IJ-fu portion.

Since the insulator clamps 60 and 62 themselves retain sufficient frictional force to provide the desired watertightness and mechanical grip, excess frictional force can be removed and the installation force required reduced. .

3 and 4, another electrical cable 110 is similar to cable 10, having a central conductor 112 surrounded by an insulator 114; 114 is surrounded by a conductive shield 116.

Another cable attachment constructed in accordance with the present invention is shown in the form of an electrical connector elbow 120, which is adapted to be attached to the end of cable 110.

The shield 116 of the cable 110 is terminated at 122, exposing a length of the insulator 114, and the insulator 114 is terminated at 122.
A length of conductor 112 terminated at 24 and terminated at 126 is exposed.

The elbow 120 is made of an electrically conductive elastomeric elastic material.
It consists of a sleeve-shaped composite housing 128 having a section 130 and a second section 132 of insulating, elastomeric, resilient material integrally molded therewith.

A mounting fitting 134 is crimped onto the exposed portion of the conductor 112, and a screw hole 136 is provided at the tip thereof.

The end of cable 110 with attached fitting 134 is inserted into an axially extending hollow bore-shaped opening 140 in housing 128 in the direction indicated by arrow 142 in FIG.

The cable 110 is connected to the housing 1 as shown in FIG.
28 into the housing 128 until it is in place on the cable end.

Once housing 12B is so positioned over cable 110, electrical connector bin 150 is inserted into threaded hole 136.
The pin 150 is attached to the fitting 134 by screwing in the threaded end 152 of the pin 150 to complete the installation.

The relative dimensions of the opening 140 and the cable 110 are such that the opening portion is elastically expanded and the corresponding portion of the cable is tightened with sufficient clamping force to ensure proper watertightness, insulative integrity, and electrical connection. and in a relationship that provides mechanical integrity.

Therefore, the opening 140 portion, the insulator tightening portion 162, has an inner diameter slightly smaller than the outer diameter of the insulator 114, and that portion 162 tightens the insulator 114 to ensure watertightness between the insulator 114 and the shield. 116 end 122 and mounting bracket 1
34 and provides a strong mechanical connection between the housing 128 and the cable 110.

As already mentioned for the terminal device 20, the elbow 120 is located on the end of the cable 110 -\ housing 1
28 is installed using lubricant 165 to facilitate installation.

To solve the problem of wiping lubricant 165 from the surface of the cable 110 during installation, the aperture 140 has an inlet passage 166 at its open end 168, which inlet passage 166 has a first tapered portion 170. and second taper part 172
It has an expanded shape consisting of.

The first tapered portion 170 is tapered from the maximum diameter at the open end 168 to a smaller first predetermined diameter DD1, while the second tapered portion 172 is tapered from the first predetermined diameter DD1 to a smaller first predetermined diameter DD1. A taper is provided that narrows toward an even smaller second predetermined diameter DD2.

The taper of the first taper portion 170 is the same as that of the second taper portion 17.
2 and the predetermined diameters DD1 and DD2 are axially spaced such that each portion 170 and 172 performs the function described above for the terminal device 20.

As in previously described embodiments, the second predetermined diameter DD2 is preferably equal to the inner diameter of the insulator clamping portion 162 of the aperture 140, and the second tapered portion 172 is entirely within the first portion of the housing 128. a second predetermined diameter DD within a range of 130 and axially spaced from the boundary between the first portion 130 and the second portion 132 toward the open end 168;
2, and the insulator tightening part 162 is the first part 130.
It extends into the inside.

Thus, any gap 174 is
It will be surrounded by portion 130.

A relatively steeply tapered first taper portion 170 and a more gradual taper second taper portion 172 of the inlet passageway 166.
It is desirable to have an expanded shape that at least approximates an exponential function surface.

The opening 140 has yet another hollow hole portion, IJ.
There is an IJ-fu portion 176 located deep within the insulator clamp 162 and having a larger inner diameter than the insulator clamp 162 and preferably a larger inner diameter than the insulator 114.

This IJ IJ-fu section 176 is attached to the insulator 114 inside.
It acts as a relief part that reduces the frictional force along the .

Yet another portion of composite housing 128, third portion 180, is integrally molded with first portion 130 and is made of a conductive elastomer.

This third portion 180 is located around the IJ-F portion 176 of the opening and relieves electrical stress in the vicinity.

It will be understood that the above detailed description of embodiments of the invention is given by way of example only.

Changes may be made in various details of design and construction without departing from the true spirit and scope of the invention as described in the claims below.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view of an electric cable terminal device in which the electric cable attachment amount of the present invention is applied to the electric cable terminal device, and is a front view and a longitudinal cross-section of the electric cable and other parts necessary to construct the cable terminal portion. Both the figure and the partially cutaway front view are shown. FIG. 2 is a partially cutaway front view showing the structure of the terminal portion of an electric cable constructed using the terminal device of the present invention shown in FIG. Fig. 3 is a vertical sectional view of a connector elbow of an electric cable when the electric cable attachment of the present invention is applied to the connector elbow of the electric cable, and the electric cable and other parts necessary for assembling it at the end of the cable are partially cut. A front view and a front view are shown. FIG. 4 is a partially cutaway front view showing the structure of the terminal portion of an electric cable constructed using the connector elbow of the present invention shown in FIG. 3. 10... Electric cable, 12... Conductor, 14...
Insulator, 16... Shielding body, 20... Terminal equipment, 28
...Sleeve-shaped member, 30...First portion, 32...
- Second part, 40... Opening, 60... Another insulator tightening part, 62... Insulator tightening part, 65... Lubricant, 66... Inlet passage, 68...・Opening end, 70・
...Part of the first taper, 72...Part of the second taper, 76
・・・IJ IJ-F part, 110... Electric cable,
112...Conductor, 114...Insulator, 116...
Shield, 120... Connector elbow, 128...
Sleeve-shaped composite housing, 130...first portion, 1
32... Second part, 140... Opening, 162...
Insulator tightening part, 165... Lubricant, 166... Inlet passage, 168... Open end, 170... Part of first taper, 172... Part of second taper, 176...・IJ
IJ-F part, 180...Third part, Dl...First
Predetermined diameter, D2... second predetermined diameter, DDl... first predetermined diameter, DD2... second predetermined diameter.

Claims (1)

[Scope of Claims] 1. In an electric cable attachment that is attached to the end of an electric cable consisting of a conductor, an insulator around the conductor, and a conductive shield around the conductor using a lubricant to facilitate installation, The insulator has an open end through which the exposed cable end is inserted, and an axially extending opening for receiving the cable end, and the insulator is firmly fastened into the opening. an elastically expandable insulator clamping part for
A sleeve-like member of elastomeric resilient material having an inlet passage extending between the insulator clamp and an open end, the inlet passage extending radially from the insulator clamp toward the open end. The inlet passageway has an inner diameter at the open end that is substantially larger than the outer diameter of the cable end, and the inlet passageway has an axially extending diameter from the open end to a maximum diameter at the open end. A part of the first taper is tapered to a first predetermined diameter at a distance from the opening, and a part of the first taper is tapered to a second predetermined diameter that is in contact with the insulator tightening portion of the opening. The second tapered
The inside diameter at the open end of the inlet passageway is large enough to allow lubricant on the cable to enter the opening, and the first predetermined diameter and the second predetermined diameter The diameter is defined as the relationship between the second tapered part of the entrance passage and the cable with exposed insulation so as to ensure that the cable is firmly clamped at a position along the second taper part of the entrance passage. Electrical cable attached quantity. 2. The electric cable appendage according to claim 1, wherein the first predetermined diameter and the second predetermined diameter are both smaller than the outer diameter of the cable end portion where the insulator is exposed. 3. The electrical cable accessory of claim 1, wherein the taper of the first taper portion of the artificial passageway is steeper than the taper of the second taper portion of the entrance passageway. 4. The electric cable attachment amount according to claim 3, wherein the expanded inner surface of the artificial passageway has a shape that approximates at least an exponential function surface. 5. The electric cable attachment amount according to claim 1, 2, 3, or 4, wherein the second predetermined diameter is equal to the diameter of the insulator tightening portion of the opening. 6 The opening includes another insulator fastening part that is spaced apart from the first insulator fastening part in the axial direction and is elastically expandable for firmly fastening the insulator, and a first insulator fastening part. and another insulator clamp, the attachment having a diameter larger than the diameter of the two insulator clamps to reduce frictional forces along the insulation therein. 5. The electric cable accessory amount according to claim 1, 2, 3, or 4, characterized in that there is an IJ-F portion. 7. The electrical cable accessory of claim 6, wherein the second predetermined diameter is at least equal to the diameter of the first insulator clamping portion of the opening. 8. The sleeve-like member of elastomeric-elastic material is a composite member having a first portion of electrically conductive elastomeric-elastic material and a second portion of insulating elastomeric-elastic material, and the inlet passageway is formed entirely of the above-mentioned material. Claim 1, characterized in that it is located within the first portion of the composite member.
Electrical cable accessories listed in section. 9. The electrical cable accessory of claim 8, wherein at least a portion of the aperture's first insulator clamp is located within the first portion of the composite member. 10. The electrical cable accessory according to claim 9, wherein the first predetermined diameter and the second predetermined diameter are both smaller than the outer diameter of the cable through which the insulator is exposed. 11. The electric cable accessory according to claim 9 or 10, wherein the second predetermined diameter is equal to the diameter of the insulator clamping portion of the opening. 12 opening includes another insulator fastening part that is spaced apart from the first insulator fastening part in the axial direction and is elastically expandable for firmly fastening the insulator; and another insulator clamp, the mounting includes a relief having a diameter larger than the diameter of the two insulator clamps to reduce frictional forces along the insulator. An electric cable accessory according to claim 9 or 10, characterized in that there is a portion. 13. The electrical cable accessory of claim 12, wherein the second predetermined diameter is at least equal to the diameter of the first insulator clamping portion of the opening. 14 The opening has a relief part located beyond the first insulator fastening part in the direction away from the opening end, and the IJ-F part is attached by frictional force along the insulator inside. 11. An electrical cable accessory as claimed in claim 9 or claim 10, characterized in that it has a larger diameter than the insulator clamping portion in order to reduce the damage caused by the insulator. 15. The electrical cable of claim 14, wherein the sleeve-like member of elastomeric elastomeric material has a third portion of electrically conductive elastomeric elastomeric material extending around the relief portion of the aperture. Accessories.