US1941731A

US1941731A - Transmission line

Info

Publication number: US1941731A
Application number: US258097A
Authority: US
Inventors: Arthur O Austin
Original assignee: Ohio Brass Co
Current assignee: Ohio Brass Co
Priority date: 1928-02-29
Filing date: 1928-02-29
Publication date: 1934-01-02
Anticipated expiration: 1951-01-02

Description

Jan; 2, 1934. Q AUSTW 1,941,731

TRANSMISSION LINE Filed Feb. 29, 1928 Patented Jan. 2, 1934 TRANSMISSION LINE Arthur 0. Austin, near Barberton, Ohio, assignor, by mesne assignments, to TheOhio Brass Company, Mansfield, Ohio, a corporation of New Jersey Application February 29, 1928. Serial No. 258,097

8 Claims.

This invention relates to electrical transmission lines and has for one of its objects the provision of means for reducing vibration in supported strands or conductors. A further object is :to

v:Jprovide a combined dampening device and a flux control member. A further object is to provide an apparatus of the class named which shall be of improved construction and operation. Other.

objects and advantages are apparent from the Jfollowingdescription.

The invention is exemplified in the combination and arrangement of parts shown in the ac-.

companying drawing and described in the following specification and it is more particularly .pointed out inthe appended claims.

. In the drawing:

Fig. 1 is an elevation of a suspension insulator string having a conductor carried thereby and having one embodiment of the present invention 30 .applied thereto.

Fig. 2 is an elevation on line 2-2 of Fig. 1. Fig; 3 isan elevation partly in section showing onemodification of the invention. Fig. 4 is a view similar to Fig. 3 showing a furither modification.

Fig. 5is a view similar to Figures 3 and 4 showing another modification;

Fig. 6 is a fragmentary, sectional view of another modification. I Fig. 7 is a transverse sectional view vice of Fig. 6.

In building high voltagetransmission lines, it is desirable to string the conductors at a high tension so that the number of supports may be reduced or ample ground clearance be provided. Itis also desirable to maintain suiiicient tension in the conductor so that danger of the conductors swinging together will be less for a given spacing or separation. As the tension increases, trouble from vibration, which tends to destroy the conductor'or attachments seems to increase. The tension, mass, and size of the conductor are apparently factors in setting up this vibration. In some cases, the conductor has been seriously damaged in a comparatively short time due to 2 .this vibration. The vibration, in general, is in a vertical direction and is apparently caused by the action of wind upon the conductor.

"The amount of energy maintaining the vibrationis usually very small. Therefore, any slight of the deabsorption of energy produced by the oscillation or vibration of the conductor will suflice to dampen it out or maintain it within safe bounds. While it is possible that a change of mass in the conductor may change the oscillation materially,

the only sure means of limiting an oscillation is through an absorption of energy. If, therefore, any attachment having suitable mass is applied to the conductor so that the oscillation .ofthe conductor will tend to cause a movement withrespect to this mass so that energy will be dissipated, the oscillation may be kept within safe: bounds or eliminated. In general, it is advisable to apply the oscillation or vibration absorber in the vicinity of the insulator or tower: Where this is done, however, any change in the size of the conductor usually results in a much lower. flash-over voltage due to concentration of electrostatic stress upon the projecting parts. In my present invention, it is desired not only to absorb energy due to vibration but also to prevent the vibration damper or absorber from lowering the flash-over voltage. a

In Fig. 1 is shown an insulator string 10 with a clamp 11 supporting a power conductor 12.

The clamp is provided with horns 13 carrying insulators 14 on their ends thus forming insu lated flux controls similar to those describedin my prior Patent Number 1,521,743. Attached to the arm 13 are blades or projections 15 between which extends an ear 16 clamped with bolts 17-to the conductor 12. It will be seen that any vertical movement'of the conductor 12 will cause the parts to vibrate and slide on the blades 15. The pressure between the

parts

15 and 16 may be adjusted by a bolt 18 and spring 19, the bolt passing through a slot 20 in the ear 16.- The bolt and auxiliary spring may be omitted and the blades 15 relied upon to providesuflicient spring 1 pressure to afford the necessary friction. By giving proper adjustment, the friction may be regu-.

'lated between the

members

15 and 16 so that;

energy will be dissipated at this point, when the 1 conductor 12 is vibrated. The insulated control member 14 and the arm 13 furnish mass so that they will tend to stay in position regardless of the movement of the conductor 12 and thus serve as a stabilizer for the conductor. It is evident. that'the absorbing

members

15 and 16 can be located at any distance from the support 10, de- 0.

sired and if properly formed, ample movement will be allowed so that the sag in the conductor may vary without disengaging the friction members. By means of the adjusting screw 18, the

friction may be adjusted over a wide range and maintained for a long time so as to permit appreciable wear without interferingwith the operation of the device. v I a To one familiar with performance at extra high voltages, it is seen that the member 13 and in- 110;

sulated control 14 may be so located that they will not reduce the flash-over voltage and under many conditions may be used to increase the flash-over voltage. This is more fully explained in Patent Number 1,521,743 referred to above. The member 13, in addition to holding the insulated control 14, also serves as an arc protection for the conductor in case flash-over voltage takes place.

The absorbing means may be made in a number of different ways such as in the form of a small dash pot 21, using oil or viscous liquids as shown in Fig. 4. Another method of providing an absorbing means is to use a plunger as shown at 22 in Fig. 3 or a sleeve working in a mass of sand, viscous liquid or particles 23 which will cause friction by relative movement of the parts. This has considerable latitude and by properly proportioning the parts, the friction or absorption may be varied within wide limits. The elements 21 and 22 will be suitably articulated as shown at 24 to permit alinement of the parts.

Another form is shown in Fig. 5. In place of the frictional surfaces working directly from the conductor, a shock or vibration absorbing element 25 is attached to the conductor by two arms 26 and 27. The vertical movement of the condoctor 12 tends to cause the frictional surfaces at 24 to slip upon each other and absorb energy. The frictional surfaces may be located at any portion of the device where there is relative movement as at 28 or 29. By properly placing this element, it is possible to shield it by the insulated control 13 so that it will lower the flash-over but little, if any. It is seen that the parts attached directly to the conductor can be quite light so that the tendency to set up a node or hard spot in the conductor will be reduced to a minimum. The pivotal point 28 will tend to stay in position during vibration of the conductor because of the inertia member 14 connected to the arm 13, as in the other forms previously described.

In the form of the invention shown in Figs. 6 and T, a bellows is connected to the conductor 12 in such a way that vibration of the conductor pumps air through a small orifice shown at 31. The resistance to the passage of air through this orifice affords the necessary resistance to dampen out vibrations. The bellows may be made of thin sheet metal and is preferably so constructed that a slight movement will produce a relatively large interchange of air. This will give considerable resistance to vibrations of small amplitude. In order to permit greater relative movement, the bellows 30 may be provided with a plunger 32 which has a yielding connection with the support 13. In the embodiment illustrated, this is represented as frictional engagement but other yielding connections. may be employed. It is apparent that where the vibrations exceed that permitted by the bellows, the additional movement will be accommodated by the frictional movement between the plunger 32 and its cooperating socket member 33 which is pivoted at 34 to the horn 13.

- In order to prevent excessive opening of the bellows, any suitable form of stop may be employed. That illustrated in the drawing comprises a housing member 35 which surrounds the bellows 30 and limits the upward movement of the plunger 32.

I claim:

1. The combination with a conductor of a support for said conductor, a weighted member adjacent said conductor but spaced therefrom, means other than said conductor for supporting said member, and energy absorbing means held by said weighted member and connected with said conductor for resisting vibration of said conductor relative to said member.

2. The combination with a conductor of a support for said conductor, a weighted member spaced from said support, means for holding said weighted member in position to permit vibration of said conductor relative to said member, and frictional contact members secured to said conductor and member respectively and having frictional engagement with each other to resist vibration of said conductor and to absorb energy producing such vibration.

3. The combination with a conductor of a support for said conductor, an arm projecting from said support, a member carried by said arm at a point spaced from said support and having movable frictional connection with said conductor for resisting vibration of said conductor, and a dielectric covering for a portion of said member forming a flux control for reducing the tendency to discharge from said member.

4. The combination with a conductor of means comprising an insulator for supporting said con ductor, an arm projecting from said supporting means along said conductor, an insulating cover carried by the end of said arm and yielding connection between said conductor and arm for dampening vibrations of said conductor.

5. The combination with a conductor of means comprising an insulator for supporting said conductor, an arm carried by said supporting means and extending along said conductor, a sleeve fixed to said conductor, friction plates carried by said arm and sleeve respectively, an insulator disposed over the end of said arm, and adjustable, resilient means for regulating frictional contact between said friction plates.

6. In combination a conductor, a support for said conductor, a bracing member carried by said support and a contact device secured to said conductor to move therewith and having yielding I frictional connection with said bracing member substantially at the point of maximum movement of said contact device and at a point spaced from the point of support of said conductor.

7. The combination with a conductor, of a stabilizer for said conductor, disposed adjacent thereto a bellows connecting said conductor with said stabilizer and having a restricted passage thereto, said bellows having frictional connection 180 at one side thereof to permit relative movement between said conductor and stabilizer of greater amplitude than the range of movement of said bellows.

8. The combination with a conductor, of a 136 stabilizer for said conductor disposed adjacent said conductor, a dampening device for said con ductor' comprising an energy absorbing member connected between said conductor and stabilizer and providing for a comparatively small range of 140 movement of said conductor relative to said stabilizer, and a resistance connection holding said energy absorbing member in place between said conductor and stabilizer and providing for relative movement between said conductor and 145 stabilizer in excess of that provided by said energy absorbing member.

ARTHUR O. AUSTIN.