US2050898A

US2050898A - Electrical insulator

Info

Publication number: US2050898A
Application number: US677113A
Authority: US
Inventors: Howard P Seelye
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-06-22
Filing date: 1933-06-22
Publication date: 1936-08-11
Anticipated expiration: 1953-08-11

Description

Aug. 11, 1936. H. P. SEELYE ELECTRICAL INSULATOR Filed June 22 1955 Patented Aug. 11, 1936 2,050,898

UNITED STATES PATENT OFFICE ELECTRICAL INSULATOR Howard P. Seelye, Royal Oak, Mich.

Application June 22, 1933, Serial No. 677,113

9 Claims. (Cl. 173-321) This invention relates to improvements in elecpu Out Of the insulating p during the trical insulators of the single knob type which twisting movement of installation. form the support for one or more electric wires Anether O j ct of y v on s to s fasten or cables. Such devices are in wide use where the screw in the Porcelain p that the p is electric wiring is supported from cross arms, ve y distributed entirely heroes the base of 5 brackets, posts or the exterior of buildings. The the letter and insures servieeebility 1 t0 the conductors are mounted on such insulators either limit 0f the strength of the porcelain e Which at an intermediate point or the end of a stretch the insulating p is C st ucted. of wire. In either .event the insulators are in A further Obje t O my invention is to provide tended to withstand the stresses imposed by the e fastening between the screw and the insulat- 10 tension of the wiring. The wiring may thus be illg p which by reason of its mode of pp carried ar u d corner or h 1 by th end of tion tends to provide a thoroughly reliable firm its length from the support. In the latter ina e t b w the p stance this condition is referred to as dead other Objects of y inventi0n Will be found ending d th full tension of t length of t to follow from the specific characteristics of the 15 wire is applied to the insulator in a sin le didevice as illustrated in the a p yin drawrection. Insulators of this type must, therefore, in which,

be able to withstand the stress imposed by the e 1 is a side elevation of the insulator; weight and the tension of a line of wire regard- Fig. 2 is a Vertical Section 011 the line 0f less of the direction in which this stress is 20 applied, Fig. 3 is a vertical elevation on the line 3-3 of To meet these situations, insulators must be and of simple, cheap and rugged construction so 4 is a bottom V w P y in ction. I that they can be affixed in position by the line- As illustrating the preferred form and the men without the use of e i l t l or h essential features of my invention, I have shown 25 exertion of undue force. In service the devices y y Of eXemDIe an insulating b b 01 must be inherently capable of withstanding the the like This knob is generally yl d ical in stresses produced. form and has a fiat circular base 6. The upper It is a prime consideration in such insulators portion 7 0f the knob is grooved t0 D Vide tWO that the fastening members such as wood screws, or more heads 8 by which the electrical pa of 30 bolts or the like shall be firmly held by the leakage is increased a d greater ac y P insulating part but at the same time removed Vided di t -W res.

as far as possible from the wire-attaching part The upper end of t b 5 es a Saddle sothat the electrical path of leakage is as great 9 which is also customary for dat g 5 as possible. either the electric wires to be supported or the The best and most commonly used material tie-Wires thereforfor the insulating knobs of this type is porce- A central opening It f s a passageway lain. However, it is not feasible to apply a metransversely through he upp p 1 f he tallic wood screw or other fastening directly to knob and is adapted to receive the electrical the porcelain itself during manufacture since if conductor or Wire and to permit the latter to be 40 the screw is molded in the plastic porcelain and j up to insulator from any direction the latter then fired, the temper of the steel in Wlthout meetmg sharp edges the screw is drawn, the screw is deformed and Thepase 6 of the knob has recess H extend the shrinkage during drying of the porcelain remg axially from} the but not as far sults in separation from the screw. Imbedding ig ifi g ifi g g' 2: #5 5? jg q' 45 s is 25555125; 1 ;ggifi i gg sfii z iz i gi 3; extended or flattened as more clearly illustrated in Figs. 2 and 4. fastening substance may disintegrate and it is The central portion of the recess has an diflicult to design a screw-head which will withlargement of circular cross section fo 50 stand torsion. grooves I2 in the side walls for the purposes of y p v deslgh as here described p t guiding and centering the shank of the screw. the assembly i a mp d cheap manner f This screw has been illustrated as a wood t fastening means in t e i sulating member screw l3 although a machine bolt, lag screw or 5,5; so that there can be no possibility of the screw the like can also be used as circumstances may dictate. The screw i3 is of the type which can be threaded into wood without previously boring a hole. The shank H5 of the screw is generally cylindrical and terminates in a flattened eye 15. This eye l5 conforms closely to the cross-section adopted for the recess M in which latter it is positioned as shown in the drawing. The eye extends near the top of the recess but not in contact therewith so that its ultimate position will be determined by the fastening means.

The fastening means consists of a transverse bolt it. This bolt is in the form of a rod of copper or like material having a flaring head H and a hollow opposite end l8 normally of the same diameter of the bolt it. This bolt serves as a rivet and the end l8 can be swagedor upset to compress the rivet and cause the metal thereof to flow laterally. I

A passageway 59 is provided in a lower portion of the insulating knob 5 and is preferably arranged in a direction perpendicular to the axis of the opening ill. The ends of the passageway B9 are counter-sunk or flared as clearly shown in Fig. 3. The passageway i9 is only large enough to permit insertion of the rivet I5 so that the headil will rest against one opening it and the opposite end it can be flared by swaging or upsetting to engage the opposite opening 2?].

The insulator as above outlined permits the assembly of fastening means to an insulator knob of porcelain or analogous pre-formed material.

In making the insulator the eye 15 of the screw-eye i3 is inserted in the recess l l with the opening of the eye in registry with the transverse passageway lQ.

In the course of this movement the cylindrical shank M is guided and centered by the grooves l2, l2 so that the screw-eye I3 will extend in a direction perpendicular to the plane of the base 6. The rivet i6 is then passed transversely of the passageway l9 and through the eye of the screw-eye. A simple upsetting or swaging operation serves to compress the rivet it so that the end 88 is spread and the rivet prevented from endwise movement. At the same time the metal of the rivet i6 is caused to flow to an extent sufiicient to completely fill the passageway 89 and the eye l5. At the same time the shank M is held by the grooves l2, 112. It follows that the screw cannot rock out of its position perpendicular to the plane of the base 6 and further that the engagement between the eye 85 and the rivet i6 is such as to prevent the screweye 53 from becoming loose or from being pulled out of the knob 5.

Even greater strength may be given this fastening by filling the recess H and the intersecting parts of the screw-eye l3 and rivet it by means of a substance which will anchor the parts together and extend the area of contact with the knob 5. One such means is molten lead which can be poured down around the screw and into the various crevices around it and also around the intersecting cross-pin. This provides a form of cushion and evens or distributes the strain. Other forms of cement or anchoring substances are equally effective.

The knob so assembled may be attached to any convenient support by manual force. The screw it can be started into the wood of the support by a light blow after which the knob forms a convenient handle by which the screw may be twisted and thus drawn up until the base 6 is in contact with the surface of the support.

The heads ll and E8 of the rivet are countersunk beneath the surface of the knob 5 and on a line circumferentially spaced from the ends of bore [9 and may if desired be covered with insulating cement or other material so that the path of leakage is further obstructed. The rivet l6 extending diametrically across the knob provides for the distribution of any strain that may be imposed during the twisting of the knob. At the same time the lateral extension of the recess H to accommodate the eye l5 permits the latter to have an extended bearing in the knob 5 and thus minimize torsional strain. This cushioning effect is even greater when lead or other cement is poured into the recess around the screw-eye andcross-pin as above described.

While I have illustrated the preferred form of the device'for the purpose of example, there are many changes in details and arrangements which are within the scope of the invention defined in the following claims.

What I claim is:

1. In an insulator, an insulating member havan upper transverse wire-receiving opening, a. rectangular recess axially through the base of the member, a lower transverse passageway intersecting the recess, a screw-eye having a flattened eye positioned in the recess and in extended contact with the side walls of the latter, and a member in the passageway passing through the eye of said screw-eye. 2. In an insulator, an insulating member having an upper transverse wire-receiving opening, a rectangular recess axially through the base of the member, a lower transverse passageway intersecting the recess, a screw-eye having a flattened eye positioned in the recess and in extended contact with the side walls of the latter, and a rivet through the passageway and the eye of the screw-eye and upset.

3. In an insulator, an insulating member having an upper transverse wire-receiving opening, a laterally extended recess axially through the base of the member, a lower transverse passageway intersecting the recess, a screw-eye having a flattened eye positioned in the recess and in extended contact with the side walls of the latter, and a member in the passageway, passing through the eye of said screw-eye.

4. In an insulator, an insulating member having an upper transverse wire-receiving opening, an axial recess through the base of the member, guide grooves in said recess, a lower transverse passageway intersecting the recess, a shouldered screw-eye and a member in the passageway and drawing the shoulder of the screw-eye into said guide grooves.

5. In an insulator, an insulating member having an upper transverse wire-receiving opening, an axial recess through the base of the member, a lower transverse passageway intersecting the recess, a screw-eye in the recess and a deformable rivet in the passageway and passing through the eye of said screw-eye.

6. In an insulator, an insulating member having an upper transverse wire-receiving opening, a recess through the base of the member, said recess being oblong in cross-section, a groove extending axially of the member centrally of each long side of said recess, a lower transverse passageway intersecting the recess in the same plane with said grooves, a screw-eye in the recess and a deformable rivet in the passageway 7'5 and passing through the eye of said screw-eye.

7. In an insulator, an insulating member having an axial recess through the base thereof, a transverse passageway intersecting the recess, a screw-eye in the recess, a member passing through said screw-eye, and anchoring means in the recess around said screw-eye and member.

8. In an insulator, an insulating member having an upper transverse wire-receiving opening, a laterally extended recess axially through the base of the member, axial guide grooves in said recess, a lower transverse passageway intersecting the recess centrally thereof, a shouldered screw-eye and a member in the passageway passing centrally through the screw-eye and drawing the sides of the latter into extended torsional contact with the walls of the recess around the said lower transverse passageway.

9. In an insulator, an insulating member having wire holding means, a recess extending axially into the base of the member, said recess having opposed parallel fiat sides, an attaching member insertible into said recess and having one end formed with similar opposed flat sides and means for holding the end of the said member in the recess with the sides of the member in extended contact with the sides of the recess.

HOWARD P. SEELYE.