US2112053A - Grounding fitting - Google Patents

Description

March 22, 1938. e. c. THOMAS. JR 2,

GROUNDING FITTING Filed Sept. 24, 1955 2 Sheets-Sheet l INVENTOR GEORGE C; THOMAS JR.

Match 8- G. c. THOMAS, JR

GROUNDING FITTING' Filed Sept. 24, 1935 2 Sheets'Sheet 2 w o h EOE INVENTOR GEORGE G.

yMAS JR ATTORNEYS Patented Mar. 22, 1938 UNITED" STATES 2,112,058 GBOUNDING FITTING George C. Thomas, Jr., Westiield, N. 1., assignor to' The Thomas & Betta-Cm, Elizabeth, N. 1., a corporation of New Jersey Application September 24, 1935, Serial No. 41,847

' 1 Claims. -(Cl. 173-273) The invention relates to a grounding fitting by means of which a wire which is connected with electrical apparatus may be grounded tov a me. tallic conductor, such as a water pipe, grounding 5 rod, many other means which is provided for establishing electrical connection with the ground. The invention relates particularly to a grounding fitting in which the wire to be grounded serves as its own hinge pin for the clamping members which grip the grounded electrical conductor. Be-

cause of the fact that the wire to be grounded serves as a hinge-pin, it is firmly pressed into contact with the two clamping members of the grounding fitting and thereby establishes a good 5. electrical contact with both members. Other elements of the invention will be more apparent V a grounded electrical conductor therebetween.

The user may select one of a plurality of positions relatively to a. clamping seat upon a clamping member and thereby adapt the fitting for different sizes of conductors or pipes.

0' Another object of the invention is to construct a grounding fitting in which the wire to be grounded serves as its own hinge pin between the two clamping members forming part of the grounding fitting and in which at least one of the clamping members is provided with a pinrality of hinge bearings so that the one grounding fitting is adapted to clamp various sizes of pipes, rods, and other grounded electrical conductors merely by selecting the hinge bearing best e suited for the size of grounded conductor to'which the fitting is to be clamped.

Another object is to devise a reeniorcing memher for the wire to be grounded at the point where it serves as a hinge pin 1 or the two clamping members of the. grounding fitting and which rceniorcing means also serves as a retaining means for holding the two clamping members of the grounding fitting together prior to the use of the grounding fitting in service.

A'still further object is to construct a grounding fitting in which the wire.to be grounded serves as its own hinge pin for the two clamping members and which fitting is provided with a bearing for the armor surrounding the grounding wire so that the armor also establishes electrical contact with the grounding fitting and is clamped I in position in its bearing upon tightening oi the grounding fitting upon an electrical conductor. It the wire is covered with insulation instead of armor, then the insulation is gripped in the bearing.

Another object of the invention is to devise a grounding fitting having two clamping members, at least one of which carries a plurality of hinge bearings for receiving, as a hinge pin, the wire 10 to be grounded so that the grounding fitting is adapted for various sizes of electrical conductors, and to reeniorce the portion carrying the plurality of hinge bearings, at the point where this portion joins the portion of the clamping member 15 having the clamping seat, with a rib which-extends lengthwise of the clamping member and serves also as a holding means for the head of an operating bolt by which the clamping members are forced together to grip the electrical conductor to which the wire is adapted to be grounded. 20

A further object of the invention is to construct a grounding fitting having an insertable clamping seat by which the grounding fitting is adapted to clamp a smaller size of electrical conductor than 2 that which the grounding fitting is capable of 5 receiving and clamping without the insertable clamping seat.

Other objects of the invention will be more apparent from the following description taken in connection with the accompanying drawings showing the preferred embodiments of the invention, in which:

V Figure 1 is an exploded view of the two clamping members of the grounding fitting preparatory to being assembled upon a grounded metallic conductor which in the illustration is shown as a pipe.

Figure 2 is a side view of the grounding fitting assembled and gripping the grounded pipe. The wire to be grounded is inserted in one of the 40 plurality of hinge bearings provided so that it serves as a hinge pin for the two clamping members.

Figure 3 is a top viewoi the grounding fitting, or as viewed from the left-hand side of Figure 2 45 with a grounded pipe gripped therein and the wire to be grounded serving as a hinge pin between the two clamping members.

Figure 4 is a'view from the other side of the grounding fitting shown in Figure 2, or from the 50 right-hand side of the latter view.

Figure 5 shows the grounding fitting with the wire to be grounded inserted in another of the hinge bearings so that the grounding fitting is adapted to grip a smaller diameter of grounded 55 conductor which is shown as being a smaller diameter of pipe than that shown in Figures 1 through 4. I

Figure 6 shows a clamping seat which is insertable into position over the clamping seat of one of the clamping members of the grounding fitting so that the grounding fitting is capable of gripping a smaller diameter grounded conductor than that which the grounding fitting is otherwise adapted to receive and clamp.

Figure 7 is a front view of the insertable clamping seat of Figure 6.

Figure 8 is a view showing the back of the insertable clamping seat of Figure 6.

Figure 9 is an assembly view of the grounding fitting with the insertable clamping seat of Figure 6 in position in the grounding fitting and gripping a smaller diameter of grounded conductor.

Figure 10 is a cross section through the hinge bearings of the grounding fitting, taken on line Iii-l of Figure 9, and shows how the grounding wire is gripped in the hinge bearings in contact with both clamping members.

Figure 11 is a top view of the grounding fitting of Figure 9 showing the manner in which the insertable clamping seat is secured in position and also showing a section through the hinge bearings with the grounding wire serving as the hinge pin and the grounding wire being strengthened or stiffened by a reenforcing bushing.

Figure 12 is a front view of the reenforcing means or bushing which is insertable over a smaller diameter wire and serves to reenforce the wire as a hinge pin and also serves to retain the two clamping, members together in assembled relation when the grounding fitting is not in use.

Figure 13 is an end view of the reenforcing hinge bushing of Figure 12.

The grounding fitting of the invention provides a simple construction by making the grounding wire serve as its own hinge pin or fulcrum between the two clamping members which grip the grounded electrical conductor to which the wire is to be electrically connected. Grounding fittings generally provide a separate means for securing the grounding wire to the grounding fitting and such separate means is dispensed with in the construction herein. Again, the grounding wire in serving as the hinge pin for the two clamping members of the grounding fitting also establishes direct electrical contact with the two clamping parts of the fitting so that a better electrical ground is established. As a matter of fact, a double grounding path is provided through each clamping member of the fitting. The grounding fitting of the invention also lends itself easily and readily and with a minimum number of parts to grip grounding conductors of many different sizes and shapes.

The grounding fitting includes two clamping members 20 and 2| which are hinged together with the grounding wire W serving as the hinge pin. The clamping member 20 is provided with a clamping seat 22 formed by the angularly disposed faces which carry serrations 23 for biting into the surface of the grounded conductor C, which is shown as a pipe in this figure. The serrations enable the pipe to be more firmly gripped and a better electrical connection is established by the serrations digging through any scale or dirt upon the surface of the conductor. A hinge bearing 24, which is preferably a hole,- is disposed at one end of the clamping member 20. A wire covering bearing 25 in the form of a bushing is provided in substantial alignment with the hinge bearing 24 in order to receive the armor or insulation covering with which the grounding wire may be covered. Many wires, however, are not covered. The wire covering bearing 25 is provided with the clamping member which carries the single hinge bearing which is particularly the clamping member 20 having the single hinge bearing 24-. The other end of the clamping member 20 carries a recess 26, which is preferably a. hole, in order to receive an operating means 21, such 'as the bolt shown in Figure 2.

The other clamping member 2| is also provided with a clamping seat 32 which is again formed preferably by angularly disposed siu'faces. which surfaces carry serrations 33 identical with the serrations 23 carried by the clamping member 20. The clamping member 21 carries at least one extension 34 which preferably extends substantially at right angles to the general plane of the clamping member. Two such extensions are illustrated spaced from each other and it is clear that only one or more than two may be provided if desired. Each extension 34 is provided with a plurality of hinge bearings which are spaced from each other on the extension. The preferred form of each hinge bearing is again a hole, there being three holes 35, 36 and 31 provided in each extension 34. The purpose of these spaced hinge hearings will be discussed more fully hereinafter. The other end of the clamping member 2| carries a recess 38-, which is preferably a hole, to receive the operating means, such as the bolt or screw 21 shown in Figure 2.

The clamping member 2i has a pair of reenforcing ridges 42, one of which extends from or forms a continuation of and merges with each extension 3d and then passes over the back of the clamping member 2! and widens out a spaced distance on either side of the hole 38 for the operating means. These spaced flanges or ridges 42 are spaced apart a distance so that the head 28 of the operating bolt 21 is received therein and retains the bolt against turning. Reenforcing ridges 43 are also provided upon the back of the clamping member 2B, but they do not straddle the hole 28.

The hinge bearing or hole 31 is adapted for clamping a one inch grounded pipe as shown in Figures 1 through 4. The hinge hearing or hole at is intended for three-quarter inch pipe, although a three-quarter inch pipe is shown in Figure as being gripped from the hinge hole 35. The hinge hole 35 is intended for one-half inch pipe. It is evident that the plurality of hinge holes 35, 3E and 31 are adapted to clamp more than one size of pipe so that the three hinge holes provide considerable latitude in the sizes of pipes or rods to be received and clamped between the clamping seats 22 and 32.

The operating means for forcing the clamping members together to grip a grounded conductor preferably includes the bolt or screw 21 having a square head 28, the fiat sides of which are received between the flanges 42 and prevented from turning thereby. An operating nut 45 is received on the bolt or screw 21. This operating means is preferably carried upon the grounding fitting and passes through the bolt holes 26 and 38 in the ends of the respective clamping members 20 and 2|, as previously described. Any other operating means for forcing the clamping members together to grip the grounded conductor is contemplated.

The operation of the grounding fitting will now be described. A ground wire to be electrb 'cally grounded to the metallic conductor is inserted throughthe hinge bearing 24 on the clamping member 20 and through one of-the hinge bearings 35, 36 or 31 on the clamping member 2|. This ground wire forms a hinge pin between the two clamping members which are hingediy secured together thereupon. A metallic conductor, such as the pipe 0, is then positioned between the clamping seats 22 and 32, and the operating bolt 21 is passed through the holes 26 and 38 whereupon tightening of the'opnot essential for hinge bearings.

Some grounding wires, and particularly the smaller sizes of grounding wires. carry an insulation or particularly a spirally wound metallic armor R as shown in Figure 10. A bushing or armor bearing 25 is provided having a bore 49 which is adapted to receive the armor R. Upon tightening of the operating nut M5, the side of the bore 49 grips the armor and establishes electrical connection therewith and also secures the armor within the bushing or sleeve. The bushing 25 also provides a covering for the ragged end of the armor.

In order "to adapt the grounding fitting for even smaller diameters or sizes of pipes, rods or-other metallic conductors, an insertable clamping seat Ellis provided as illustrated in Figures 6, 7 and 8. This insertable c'lampin-gseat has angularly disposed clamping surfaces having serrations 52 for biting into the pipe or rod. This clamping seat W carries means for securing the seat in place'upon one of the clamping members. Any

desirable securing means may be utilized, that illustrated comprising a pair of bendable tabs 53 projecting from the clamping seat, which tabs project beyond the edge of the clamping member 2| so that the tabs may be bent thereovenas illustrated in Figures and 11, to secure the insertable clamping seat in position. The edges 5d of the insertable clamping seat 59 engage a serration 33 on each angular face of the clamping seat 32 and the clamping seat is retained in position against shifting by the serrations. Also the sides 55 01 the insertable clamping seat 50 engage the sides of the clamping member 2| and the insertable clamping seat is additionally supported in position by this engagement. A half inch rod is shown in Figure 9 as being clamped within the grounding fitting utilizing .the insertable clamping seat 50. It is clear that by properly proportioning the insertable clamping seat, smaller diameters of pipes or rods as well as various shapes of pipes and rods may be clamped within the grounding fitting. It is clear also that, if desired, an insertable clamping seat may be used for each of the clamping members 20 and 2!,

If the grounding wire W to be clamped within the hinge bearings Hand 35, 36 or 31 is relatively small, there is some possibility that such small wire may be sheared off if the operating nut 45 is securely tightened. In order to avoid forcing means and the wire are this possibility, a reenforcingmeans 58 is. provided which is also projected through the hinge bearings with thegrounding wire. As illustrated in Figures 12 and 13, this reeniorcing means is preferably tubular or a bushing and collapsible so that under pressure in the hinge bearings, the bushingcontracts or collapses and the grounding wire W is securely anchored within the bushing and the latter and wire are both firmly clamped in the hinge bearings. Good electrical contact is therefore established between the wire W and the clamping members 20 and 2!.

, The collapsible reenforcing means 58, particu; larly illustrated, is tubular and is rendered contractile by a slot or particularly by rolling a fiat plate circularly so that the ends thereof overlap.

' With this. type or collapsible reenforclng means, there is nosubstantial deformation of the reenforcing means, other than circularly, so that the reenforcing means 58 substantially engages the entire circumference of the grounding wire W.'

'I'his'reenforcing means is shown in position in Figures 10 and 11 and under the clamping action of the operating means 21, 45, both the reengripped within the hinge bearings.

The reenforcing means 58, in addition to reenforcing a, smaller diameter grounding wire W, also serves to retain the hinge portions of the clamping members and 2! in hinged relation when in transit or boxed or at any time when the grounding fitting is not in use. The reenforcing member is merely inserted in the hinge bearing it and any one of the hinge bearings 35, 36 or 31 upon the clamping member 2! and this retains the hinge portions of the two clamping members together. Any other type of reenforcing means is contemplated, as well as any other means which is insertable within the hinge bearings in order to retain the hinge portions of the two clamping members 20 andll in assembled relation.

The invention has been illustrated as having two clampingmembers 20 and 21 one of which, namely 20, is provided with a single hinge bearing 24 and the other 2| is provided with a plurality of hinge bearings 35, 36 and 31. It is to be understood that each clamping membermay I be provided with a plurality of hinge bearings and this form is contemplated herein. Again, inthe form particularly illustrated, the relation of clamping seat, hinge and operating means is that of a lever of the second class. It is within the provinceof the invention to position these parts with respect to each other so as to havea relation of levers of the first and third class.

Various modifications will occur to those skilled in the art in the configuration, composition and disposition of the component elements going to make up the invention as a whole, as Well as in to receive a wire to be grounded and the others of which receive the ground wire for conductors of different sizes, at least one hinge bearing upon another clamping member to also receive the grounding wire which wire serves as a hinge pin between the clamping members, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, and operating means to force the clamping members together to grip the metallic conductor between the clamping seats and grip the grounding wire against the hinge bearings in which the grounding wire is received.

2. A grounding fitting for a grounding wire comprising clamping members each having a hinge bearing'to receive a wire to be grounded which wire serves as a pin to hingedly secure the clamping members together, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, operating means to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the hinge bearing, and a. reeniorcing means adapted to be placed in contact with the wire and inserted in the hinge hearings to reenforce the wire and to retain the hinge bearings together.

3. A grounding fitting for a grounding wire comprising clamping members each having a hinge bearing to receive a wire to be grounded which wire serves as a pin to hingedly secure the clamping members together, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, operating means to force the clamping members together to grip a metallic conductor between the seats and grip the grounding wire against the hinge bearings, and a contractile tubular reenforcing means received in the hinge bearings and adapted to receive the grounding wire therein to reenforce the wire and also to retain the clamping members together when not in use.

4. A grounding fitting for a grounding wire comprising clamping members each having a hinge bearing to receive a wire to be grounded which wire serves as a pin to hingedly secure the clamping members together, a receiving bearing for a wire cover carried by one of the clamping members and located in substantial alignment with the hinge bearing, clamping seats upon the clamping members between which a. metallic conductor is adapted to be clamped, and operating means toiorce the clamping members together to grip a metallic conductor between the seats, the grounding wire against the hinge bearing and the wire covering in the cover receiving bearing.

5. A grounding fitting for a grounding wire comprising clamping members, extension means carried by one clamping member and extending substantially at right angles to the general plane thereof, a plurality of spaced hinge holes in the extension means, a hinge hole in the other clamping member which hinge hole and one of those in the extension means are adapted to receive a wire to be grounded which wire serves as a hinge pin between the two clamping members, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, and operating means to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the sides of the hinge holes.

6. A grounding fitting for a groundingwire comprising clamping members, extension means carried by one clamping member and extending substantially at right angles to the general plane thereof, a plurality of spaced hinge holes in the extension means, a hinge hole in the other clamping member which hinge hole and one of those in the extension means are adapted to receive a wire to be grounded which wire serves as a hinge pin between the clamping members, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, reenforcing flange means extending from the extension means as a continuation thereof over the back of the clamping member, and operating means to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the sides 0! the hinge holes.

7. A grounding fitting for a grounding wire comprising clamping members, extension means carried by one clamping member and extending substantially'at right angles to the general plane thereof, a plurality of spaced hinge holes in the extension means, a hinge hole in the other clamp ing member which hinge hole and one of those in the extension means are adapted to receive a wire to be grounded which wire serves as a hinge pin between the clamping members, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped,

openings at the end of each clamping member, a pair of flanges extending from the extension means over the back of the clamping member and one flange passing on each side of the opening upon one clamping member, an operating bolt passing through the openings to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wireagainst the sides of the hinge holes, and a head on the operating bolt received between the flanges to prevent the operating bolt from turning.

8. A grounding fitting for a grounding wire comprising clamping members, a hinge bearing in each clamping member which hinge bearings are adapted to receive a wire to be grounded which wire serves as a pin to hingedly secure the clamping members together, clamping seats upon the clamping members between which a metallic conductor is adapted to be:clamped, openings at the end of each clamping member, a pair of flanges extending over the back of one of the clamping members and one flange passing on each side of the opening in the end of the clamping member, an operating bolt passing through the openings to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the sides of the hinge holes, and a head on the operating bolt received between the flanges to prevent the operating bolt from turning.

9. A grounding fitting for a grounding wire comprising clamping members, a hinge bearing in each clamping member which hinge bearings are adapted to receive a wire to be grounded which wire serves as a pin to hingedly secure the clamping members together, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, an insertable clamping seat received over the clamping seat carried by one of the clamping members, and operating means to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the hinge bearings.

10. A grounding-fitting for a grounding wire comprising'clamping members, a hinge bearing in each clamping member which hinge bearings are adapted to receive a wire to be grounded:

which wire serves as a pin to hingedly secure the two clamping members together, clamping seats upon the clamping members formed with angularly disposed surfaces between which seats a metallic conductor is adapted to be clamped, serrations upon the clamping seats, an insertable clamping seat received over the clamping seat carried by one of the clamping members and the edges thereof engaging the serrations upon the clamping seat to retain the insertable seat in position, and-operating means to force the clampcomprising two clamping members; a hinge bear ing in each clamplngmember which hinge bearings are adapted to receive a wire to be grounded which wire serves as a pin to hingedly secure the twoclamping members together, clamping seats upon the clamping members between which a metallic conductor is adapted to be clamped, serrations upon at least one seat, an insertable clamping seat received over the clamping seat carried by one of the clamping members, edges carried by the insertable seat engaging in the i serrations, tabs carried by the insertable' clamping seat and bendable over the edge of the clamping member, the serrations and tabsanchoring the insertable clamping seat upon the clamping member, and operating means to force the clamping members together to grip a metallic conductor between the clamping seats and grip the grounding wire against the hinge bearings.

GEORGE c. moms, JR.

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