UNITED   STATES   PATENT   OFFICE


LEONARD W. STORROR, OF SAN FRANCISCO, CALIFORNIA.

INSULATOR.


No. 882,803                     Specification  of Letters Patent.          Patented March 24, 1908.

Application filed January 2, 1906.  Serial No. 294,099.


To all whom it may concern:

Be it known that I, LEONARD W. STORROR, a citizen of the united States, and resident of the city and county of San Francisco, State of California, have invented certain new and useful Improvements in Insulators, of which the following is a specification.

Insulators are subject to leakage over their surfaces.  This leakage is caused by moisture and deposition of foreign substances from the air.  The deposition in time completely coats the surface with a layer of increasing thickness progressively impairing the insulating power of the insulator.  Various devices have been tried to overcome this defect, none of which however have met with any large measure of success.  Oil in cups has been used; but the surface of the oil becomes covered with dust in the same manner as the surface of glass and porcelain.  The wind and capillarity tend to coat the insulator surfaces with the oil placed in the cups, and thus to aid the adhesion of dust and dirt thereto.  Petticoats were added on insulators and continuously multiplied.  Insulators were added to one another.

The object aimed at has been to shed rain and keep dry the under surface of the insulator.  But they all fail to do this, since the wind carries fumes and dust to the underside, and the carbon, creosote, and oil in the smoke which the air carries, attach themselves thereto as well as to the other parts.  Capillarity attracts the moisture of fog and rain into the area of the under surface from the drip edges of insulators, and practice shows that the only good done by multiplying petticoats is, in increasing the distance which the current has to travel from the tie wire to the pin.

My invention protects part of the surface of insulators from the deposition of moisture and foreign substances.  If about the surface of an insulator there remains an unbroken zone of dryness and cleanliness, the insulating property thereof is maintained at a high standard.  It does not matter whether this zone is on the lower surface or on the outside surface of an insulator, so long as it lies between the tie wire and the junction surfaces of the pin and the insulator, its effect in insulating the current will be the same.  The degree of insulation is proportional to the width of the aforesaid zone.

The primary object of my invention is to provide an insulating device capable of resisting the leakage effects of fog, moisture and other substances.

A second object of my invention is to provide an insulating device having means of maintaining a complete zone of dryness and cleanliness around about the space between the tie-wire and the pin.

A third object of my invention is to provide an insulating device having a covering adapted to protect part of the surface thereof from deposition of moisture and other substances.

Other objects will appear in the subjoined description of my invention which is illustrated by the drawing accompanying this specification and forming part hereof.

Said drawing is a vertical central sectional view of my insulating device, showing the pin for supporting the same.

My device is primarily divisible into two parts, an upper 1, and a lower 6.  Both parts are constructed of highly insulating.  Material as glass or porcelain, and are separated from each other by air spaces. It is to be understood, however, that the separation is for constructive reasons only, and that a single device embodying the principle of my two-part insulator, is also contemplated by me.  The pin 5 may be an iron pin, having an insulating or partially insulating screw to support my insulator; or it may be an ordinary wooden pin with or without a covering of highly insulating substance.  Upper part 1 of my device may take any of the forms suitable for an insulator.

The outer petticoat is shown at 2 and the inner petticoat at 3.

The groove for suspending the line wire is shown at 4, but it is to be understood that the wire suspending means may be situated at any other desirable position, as at the top.

That p art of the surface of the insulator which is affected by leakage lies between groove 4 and the pin 5.  Attention is called to the construction of such insulators as shown in part 1 of my device.  They form a class in which, while the petticoats are multiplied, they are always open in straight lines to the outer air; that is to say, that a substantially straight line dropped from the line joining any petticoat to the body of the insulator, would

reach the open air without obstruction. The petticoats merely act to increase the distance between groove 4 and pin 5. Even where a combination of insulators of many petticoats is used, as in some of the recent insulating devices for high tension circuits, the petticoats are all related to the body of the insulator in the manner above described, and separate insulators are similarly related.  The condition will be understood by referring to the drawing and supposing the under part 6 to be absent.  The inside of petticoat 2, both sides of petticoat 3, and their lines of juncture with the body of the insulator, present a free, open, surface to the air; a surface which is reachable by substances moving upwardly in such substantially straight lines.  In other words the surface is practically unprotected from deposition of moisture and dirt carried in the air.

Attention is now directed to the lower part 6 of my device.  As shown in the drawing it comprises a body and flanges or petticoats.  The petticoats are arranged to partially fill the interspaces between the petticoats of upper part 1, but leaving an air space between their respective surfaces the drawing shows the lower part fitted to cooperate with a double petticoat insulator.  Insulators of other shapes would have corresponding 1ower parts, partially filling the interspaces between their petticoats, and partially closing the bell-like opening of the insulator.

By the illustrated device, part of the surface of upper part 1 is kept away from the before described straight line communication with the air.  This part in the drawing is the petticoat 3, the surface of which is protected on two sides by the lower part 6.  The protection consists in making the path of the air from the atmosphere to the part 3 a tortuous one, and of making the air space between the surface of said lower part and the surface of said upper part, as small as the exigencies of construction and operation will allow.

The much desired effect or maintaining a zone of dryness and cleanliness is produced by my device, the said zone being in this case the surface of petticoat 3.  And it is to be understood the more numerous the petticoats and the corresponding flanges of the lower part 6, the more perfect will be the maintenance of the said zone at the less accessible parts of the insulator, and the greater the width thereof.

The operation of my device to maintain the aforesaid zone of dryness and cleanliness is not conjectural; but I have tested it for a time sufficient to cover thickly with a carbon deposit the outer surface of part 1, and to some degree the inner surface of petticoat 2, and that part of the surface of lower part 6 adjacent to petticoat 2, while petticoat 3 remained dry and clean.

The flange or collar 8 is made heavy enough to support lower part 6 on pin 5.  As aforesaid it is best to make lower part 6 of insulating material.  The reason for making it of such material is to lessen leakage effects caused by possible connections between the adjacent surfaces of parts 1 and 6 through dust or cobwebs.  Although part 6 is shown as having its lower surface above the lower surface of upper part 1, I do not confine myself to this exact construction.  Nor do I confine myself to exact conformity between the lines of part 6 and part 1, since a shield partly covering the bell like opening of part 1 will in a measure perform a like function.

Having described my invention what I claim as new and desire to secure by Letters Patent of the United States, is:

In an insulator, a pin having its top frustoconical and threaded for a part of the length of said frustoconical top, a protecting member made of an insulating material and adapted to fit tightly on the frustoconical part of the pin for the entire depth of the said protecting member, said member also having an upwardly projecting flange whose outer surface is a portion of a cone, and a wire-carrying insulating member having internal threads adapted to fit the threads of the pin, said wire-carrying member having a skirt adapted to project down into the space between the flange on the protecting member, said wire-carrying member also having an outer skirt extending below the bottom of the protecting member.

In testimony whereof I have hereunto signed my name in the presence of two witnesses.

 

   LEONARD W. STORROR.

 

Witnesses:

FINLAY COOK,

ALFRED J. HARWOOD.