UNITED   STATES   PATENT   OFFICE


JOHN W. BOCH, OF EAST LIVERPOOL, OHIO, ASSIGNOR TO THE R. THOMAS & SONS COMPANY, OF THE SAME PLACE.

HIGH-POTENTIAL INSULATOR.


SPECIFICATION forming part of Letters Patent No. 601195, dated March 22, 1898.

Application filed February 1, 1898, Serial No. 668,770.  (No Model.)


To all whom it may concern:

Be it known that I, JOHN W. BOCH, a citizen of the United States of America, residing in East Liverpool, Columbiana County, State of Ohio, have invented an Improved High-Potential Insulator, of which the following is a specification.

The object of my invention is to produce a strong and effective insulator for high-potential electric-transmission lines, and one which will not only offer high resistance to leakage of current through the body of the insulator, but also will prevent arcing of the current from the edges of the petticoats of the insulator during wet weather, and more particularly to the metal pin which binds the insulator to the supporting-arm.  This object I attain by mounting the petticoat-body of the insulator upon an insulating-post, preferably of the same material as the body, and which passes down through an opening in the wooden cross-arm or support, the metal fastening-pin being secured in the post.

In the accompanying drawings, Figure 1 is a vertical sectional view of one form of my high-potential insulator, and Fig. 2 is a corresponding view of a modification.

I prefer to use porcelain in the construction of my insulator, both for the body of the insulator and for the tubular post; but glass or other suitable like or equivalent material may be used for either or both parts.  I prefer to make the petticoat-body in two or more parts.  In the drawings I have shown two petticoats B B', each petticoat part being like an inverted bowl, with the smaller one nested into the larger one.  At the top of the outer bowl there is a head b with a central cross-notch b' for the electric conductor and side grooves d for the wire by which the conductor is to be held down.  The central part A of the body of the insulator constitutes in this case a third part of the insulator. These three parts, if of porcelain, may be secured together either during the process of vitrification or in the glazing (if that is done separately from the vitrifaction) in order to make in effect a single homogeneous piece.  I prefer the method described in my application Serial No.  656,155, whereby the parts become united with layers of glaze between the conductor and pin; but the parts may be secured together in other ways, as by sulfur or other cement after they have been separately vitrified and glazed, if of porcelain, or molded, if of glass.

In the construction shown in Fig. 1 the tubular supporting-post P is shown as made in one with the central part A of the body of the insulator.  The tubular post may, however, be made separate from the body parts, as illustrated in Fig. 2, where the central body part A' is shown as having a central opening a (screw-threaded in this instance) for the insertion of the upper end of the supporting post P'.  This supporting-post and central part may be secured together by any suitable means as, for instance, by glaze in the course of manufacture, if the parts are to be of porcelain, or after manufacture by sulfur cement or otherwise.  The post may be made out of two molded tubes p p’, one fitted within the other and secured together by an intervening tubular layer of glaze, as indicated at g in Fig. 1.

In any construction described the supporting post P or P' is at its lower end adapted to enter an opening made in the wooden or other cross-arm C (shown by dotted lines) and an annular shoulder s is formed on the post to rest on the cross-arm and form a point of support.

The vertical opening in the support P or P' is of a diameter suitable to receive the iron or other metal securing-pin R, which is indicated by dotted lines and which extends up into the post to any desired height and is secured by a suitable cementing composition.  A nut n and a washer w (indicated by dotted lines) complete the means for securing the whole in place on the cross-arm.  In Fig. 1 the securing-pin is shown as having a polygonal head, while in Fig. 2 the pin is shown as notched to get a hold in the cement.

In the described construction it will be seen that the pin R is so well protected by the tubular post which sheaths it and passes down through the cross-arm that leakage of current or arcing across from the edges of the petticoat to the pin (liable to occur on high-potential circuits of present construction) is here obviated.  The exposed end of the pin and its nut and washer on the under side of the cross-arm are too far away from the conductor in the notch b to give trouble.

I claim as my invention--

1. A high-potential petticoat insulator having a vertical tubular post of porcelain or equivalent material, secured to and supporting the petticoats of the insulator and having its lower end adapted to fit into an opening in the cross-arm and a metal fastening-pin in the said tubular post, substantially as described.

2. A high-potential insulator having a supporting ost made in one with a part of the body of the insulator, said supporting ost having its lower end adapted to fit into an opening in the cross-arm, with a fastening-pin secured in the post, substantially as described.

 3. A high-potential porcelain insulator formed of parts united together and comprising a body part with one or more petticoats and a supporting-post all of porcelain united together the lower end of the supporting-post being adapted to fit into an opening in the cross-arm to receive a securing-pin from the under side, substantially as described.

4. A high-potential porcelain insulator formed of parts united by intermediate layers of glaze and comprising a body part with one or more petticoats and a supporting-post whose lower end is adapted to fit into an opening in the cross-arm to receive a securing-pin from the under side, substantially as described.

5. A high-potential porcelain insulator having a supporting-post made of two tubes, one fitted within the other with an intermediate tubular layer of glaze, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

      JOHN W. BOCH.

 

Witnesses:

      L. M. THOMAS,

      JOHN TAYLOR.