To all whom it may concern:

Be it known that I, RICHARD H. STERLING, a citizen of the United States, residing at Pittsfield, Berkshire county, Massachusetts, have invented certain new and useful Improvements in Insulators, of which the following is a full, clear, and exact description.

My invention relates to pole-line insulators or insulators for supporting electrical conductors which are exposed to the weather, and has for its object to produce a more efficient device and 6ne with which arcs are not so liable to form as with those now in use.

My invention is particularly useful where very high potentials are used, in which case, particularly in wet weather, there is with the ordinary insulator great danger of an arc forming around the insulator and between the line and the supporting-pin.  This danger is largely due to the fact that in the ordinary insulator the moisture or rain collects and falls in drops or small streams, by which, as is well known, a much larger amount of electricity is carried than would be by a single stream of a quantity equal to the combined drops or streams.  The potential of the air around the pin is accordingly raised and as a consequence arcing to the pin is facilitated.  Moreover, drops or small streams from an insulator when charged with electricity are attracted toward the pin on which the insulator is supported and are also easily blown toward it by the wind.  I have therefore made insulators with gutters which collect the water and discharge it in large streams at definite points, and in order to still further lessen the danger I preferably add spouts which shall deliver the water at a greater distance from the supporting-pins.

The following is a description of an insulator embodying my invention, reference being had to the accompanying drawings, in which--

Figure 1 is a view partly in elevation and partly in section.  Fig. 2 is a plan view, and Fig. 3 is a front view of the upper part.

Referring more particularly to the drawings, A is a hat-shaped insulator, of porcelain or other suitable non-conducting material, mounted upon the pin B and consisting of a petticoat C and a top piece D, connected together by cement poured into grooves E.  The top piece has a knob or crown F, with the I groove G,

through which the conductor passes and in which it is secured.  About the edge of the part D is a gutter formed by the sloping sides or rim and the flange H, in which the water collects and from which it flows through the opening I in line with the electric conductor.  The sloping sides are substantially those of a cone having a base of any suitable shape and so flattened that the pitch of the surface down which the water flows is not too steep.  In my preferred form the cone is flattened, so as to make the radius of its circular base greater than its height. In order to carry the discharge still farther from the pin, I provide a spout J.  There would be some disadvantage mechanically, both in the manufacture of the insulator and in transporting and shipping the same, in having a spout always projecting at right angles to the gutter.  I therefore make the spout separate end attachable, forming a groove K therein, in which fits a corresponding portion of the gutter-flange at the opening I, as shown.  The two parts can then be shipped separately, the spouts being attached when desired, a waterproof cement being used to make a tight joint.

It will be seen that with insulators embodying my invention the water is not permitted to drop or run off at many points, but is collected and discharged at definite points, so as to interfere with the insulating function as little as possible.

What I claim is--

1. An insulator having an upper surface in the form of a flattened cone and a substantially vertical flange about its edge forming a gutter for collecting and discharging the Water from said surface.

2. An insulator having an upwardly-projecting flange about its edge forming a gutter and means for discharging collected water said means extending a distance from said flange.

3. An insulator having on its upper surface at its edge a gutter and a detachable spout leading from said gutter, substantially as described.

      Signed March 10, 1900.

     RICHARD H. STERLING.

Witnesses:

CHARLES E. DORR,

JOHN F. KELLY.