Line-gripping and spacing device

July 10, 1962

H. J. KLEIN

LINE-GRIPPING AND SPACING DEVICE

Filed Aug. 10, 1959

3,043,902

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United States Patent Office

3,043,902

Patented July 10, 1962

3,043,902 LINE-GRIPPING AND SPACING DEVICE

Harry J. Klein, Box 150, Emporium, Pa.

Filed Aug. 10, 1959, Ser. No. 832,646

Claims. (Cl. 174—146)

This invention relates generally to the field of auxiliary equipment for use with a television or radio reception antenna, and more particularly to a device for spacing a double wire transmission line leading from a television or radio antenna to a receiver.

In localities which are located at a considerable distance from a television or radio transmitter, with intervening. hills or mountains between the receiver and transmitter, reception is often substandard. In order to improve reception . under such conditions it is a common practice to locate the television or radio antenna at some relatively high place in the neighborhood of the receiver, and to run a transmission line from the antenna to the receiver to convey the signal thereto. It is generally considered that in such applications the best type of transmission line, from the standpoint of efficiency and low signal loss, is the double wire open line type which consists of two uninsulated copper wires spaced from each other by a line-spacer which is fabricated of a dielectric material so as not to short circuit the spaced wires.

One previously known type of line-spacing device consists of an integrally molded polyethylene body having at each of the opposed ends thereof a gripper head which is designed to clamp onto one of the spaced wires of the double wire transmission line. Each of the gripper heads consists of a pair of oppositely directed Cshaped hooks. The wire to be clamped thereby is inserted between the C-shaped hooks, after which the linespacer is twisted in the proper direction to make the oppositely directed C-shaped hooks partially encircle the wire from opposite sides. The gripper heads at the opposite ends of the line spacer are arranged so that the direction of rotation which engages one of the gripper heads about one of the transmission wires is opposite to the direction of rotation which engages the other gripper head about the other transmission wire. As a result, when both wires are simultaneously engaged by their respective gripper heads they continuously exert oppositely directed torsional forces upon the line-spacing device so as to keep the wires engaged within the Cshaped hooks of the gripper heads.

The aforesaid type of line-spacing device suffers from at least two serious disadvantages. In order to install such a line-spacing device it is necessary first to engage one of the wires within one of the gripper heads, and then to twist the line-spacing device against the force exerted thereon by the wire already engaged thereby until the line-spacing device is twisted around into the proper position for engagement with the other wire. The twisting of the line-spacing device which is necessary in order to install it usually requires considerable effort, since generally the wires of the transmission line are rather tightly stretched. Furthermore, since the wires of the transmission line continuously exert oppositely directed torsional forces upon the line-spacing device, it will be appreciated that such a device is subjected to continual stress during the entire time that it is in service. When the weather becomes cold enough the thermoplastic polyethylene material of which the device is made has a tendency to become brittle, and when that happens the C-shaped hooks may break off as the result of some unusual pull exerted upon the transmission line wires, or simply as the result of the constant torsional stress to which the line-spacing device is subjected.

Accordingly it is broadly an object of this invention to alleviate one or more of the foregoing difficulties and disadvantages. More specifically, it is within the contemplation of this invention to provide a line-gripping and spacing device which is easily installed without the 5 necessity for exerting any strong twisting force thereon, and which is so designed that it grips the wires of a double wire transmission line without being subjected to constant stress during the period of use.

In accordance with an illustrative embodiment demon10 strating these and other advantageous features and objects of the invention, there is provided a line-gripper which comprises at least one unitary gripper head which is formed of an elastic material and includes a pair of jaws and a fulcrum which integrally joins the jaws and 15 which is deformable to permit an opening and closing pivotal movement of the jaws about the fulcrum. The fulcrum resiliently biases the jaws toward a closed position for gripping an object therebetween. A pair of operating arms are secured to the jaws of the gripper 20 head and extend to the opposite side of the fulcrum from the jaws, so that the jaws open and close inversely to the operating arms. The operating arms are normally spaced apart from each other when the jaws are closed, but are movable toward each other to open the jaws for 25 insertion of the object to be gripped therebetween.

The foregoing brief summary, as well as additional advantageous features inherent in this invention, may best be appreciated by reference to the following detailed description, taken in conjunction with the accompanying 30 drawings, in which:

FIG. 1 is a perspeceive view of an individual linegripping and spacing device in accordance with this invention;

FIG. 2 is a perspective view of the line-gripping and 35 spacing device of FIG. 1 illustrated as it is being compressed into the open position and placed in engagement with a transmission line wire;

FIG. 3 is a progression of side elevational views of the line-gripping and spacing device of FIGS. 1 and 2 40 showing the manner in which this device is easily installed as a spacer between the two wires of a double wire transmission line; and

FIG. 4 is a perspective view of a segment of an elongated extruded body from which individual line-gripping 45 and spacing devices in accordance with this invention may be cut during the manufacture of such devices.

Referring now specifically to the drawings, a linegripping and space device in accordance with this invention comprises a unitary body, generally designated ⁵⁰ 10, which is molded of an elastic material such as polyethylene plastic. By the term “unitary” is meant that the body 10 is molded entirely in one piece. Thus, the various parts of the body 10 of the line-gripping and spacing device of this invention, including a pair of grip³³ per heads 10&lt;z and 10Z&gt; at the opposite ends thereof and a pair of operating arms 10c and lOd therebetween, are all integrally joined and are molded into the gripper body 10 in the manufacture thereof.

Each of the gripper heads 10α and 10Z&gt; is itself a uniθθ tary structure in the sense defined above, and includes jaws 12 and 14 mounted in opposable relation to each other and a fulcrum area 16 therebetween which is molded integrally with both of the jaws 12 and 14 at the base thereof and which thus joins the jaws 12 and 14 together. The jaws ³³ 12 and 14 approach each other closely in the region 18, but are not interconnected at that region and thus are separable from each other to permit a spreading motion of the outer ends of jaws 12 and 14 so as to open the region 18 ₇θ widely for insertion of an object between the jaws 12 and 14. The fulcrum area 16 which joins jaws 12 and 4, because of the elastic material of which the unitary grip3,043,5

Ο per body 10 is molded, is sufficiently deformable to permit the jaws 12 and 14 to pivot thereabout in performing the aforesaid opening movement. Thus, when the jaws 12 and 14 are opened, the fulcrum area 16 is deformed and stressed to permit the oppositely directed 5 opening pivotal movement of the jaws 12 and 14 thereabout. The stress under which the fulcrum area 16 is placed when the jaws 12 and 14 are open causes it to exert a resilient biasing force tending to close the jaws 12 and 14 by moving them through a reverse pivotal 10 movement which brings them back into their normal close relationship in the region 18 and allows the fulcrum area 16 about which the jaws 12 and 14 rotate to return to its normal unstressed and undeformed condition. 15

The above described opening pivotal movement of jaws 12 and 14 serves the purpose of allowing insertion of an object to be gripped thereby between the jaws 12 and 14 through the then more widely opened region 18. FIG. 2 illustrates the gripper heads 10α and 106 20 in their open condition, and also shows a transmission wire 20 which is to be gripped by the lower gripper head 106 and which has been inserted between the jaws 12 and 14 thereof through the widely opened area 18. It will be readily appreciated that subsequent closing of ²⁵the jaws 12 and 14 will allow the latter to encircle the wire 20 so as to clamp thereabout for exerting a grip thereon. Between the region 18 at which the jaws 12 and 14 open and the fulcrum area 16 about which they rotate in performing their opening and closing pivotal ³⁰movement the jaws 12 and 14 are each formed with semicylindrical recesses extending transversely across the confronting faces thereof. These recesses confront each other and thus cooperate to define a cylindrical line seat 22 between the jaws 12 and 14, which, when the jaws ³³12 and 14 are closed has the appearance of a cylindrical through bore extending transversely through the gripper heads 10α and 106 and bounded by the jaws 12 and 14, the fulcrum area 16, and the region 18. The size of the line seat 22 is selected in relation to the diameter of ⁴⁰the wire 20 so that the latter will nest snugly in the line seat 22 without preventing the jaws 12 and 14 from returning to their normal position of close approach in the region 18 when the wire 20 has been inserted and the jaws 12 and 14 have been clamped thereabout.

The operating arms 10 c and 10d serve to hold the gripper heads 10α and 106 in spaced relationship at opposite ends of the gripper body 10 so that a pair of transmission wires 20 gripped by the respective gripper ,heads 10α and 106 may be spaced apart. Each of the operating arms 10c and lOd is joined to each of the gripper heads 10α and 106 at opposite ends of the gripper-body 10, and molded integrally therewith. More specifically, the operating arms are joined to respective 55 jaws of each gripper-head; that is, operating arm 10c joins the jaw 12 of each of the gripper heads 10α and 106, while operating arm 10zf joins the jaws 14 of each of the gripper heads 10α and 106. The operating arms 10c and 10zZ bear a prescribed relationship to the jaws θθ 12 and 14 of each of the gripper heads 10α and 106 as follows: The operating arms 10c and lOd extend to the opposite side of the fulcrum 16 of each of the gripper heads 10α and 106 from the jaws 12 and 14 of that gripper head. Thus, the operating arms 10c and 1(W gg extend inwardly toward the mid-section of the gripper body 10 from the fulcrum 16 of each gripper head, while the jaws 12 and 14 of that gripper head extend outwardly from the fulcrum 16 thereof toward the opposite ends of the gripper body 10. The described ar- γθ rangement wherein the operating arms 10c and lOd join respective jaws 12 and 14 of each gripper head and extend to opposite sides of the fulcrum of each gripper head from the jaws thereof causes the operating arms 10c and lOd to open and close inversely to the jaws 12 75 and 14 of both gripper heads 10a and 106. By the term “open and close inversely” is meant the relationship whereby a closing movement of the operating arms 10c and 10i/ which brings the latter closer together results in an opening movement of the jaws 12 and 14 of both gripper heads 10α and 106 which moves such jaws further apart in the above described opening movement. Conversely, opening movement of the operating arms 10c and lOd in which the latter separate from each other causes the jaws 12 and 14 of both gripper heads 10α and 106 to perform the closing movement described above in which such jaws move closer together. The operating arms 10c and 10rf are bowed outwardly from each other and thus are normally spaced apart near the mid-section of the gripper body 10 when the jaws 12 and 14 of the gripper heads 10α and 106 are closed. The normal or rest condition of the gripper body 10 is illustrated in FIG. 1, where it is seen that the operating arms 10c and 1(W are bowed outwardly and spaced from each other, while the jaws 12 and 14 of both gripper heads 10α and 106 are in the closed position. However, because the gripper body .10 is molded of an elastic material, the operating arms 10c and 10&lt;7 may be flexed toward each other near the mid-section of the gripper body 10 as illustrated in FIG. 2 to cause the jaws 12 and 14 of both gripper heads 10α and 106 to open simultaneously for insertion of wires 20 therebetween.

It will therefore be appreciated that in the operation of the line-gripping and spacing device of this invention it is only necessary when installing the device to squeeze together the operating arms 10c and lOd thereof between the thumb and finger of one hand as illustrated in FIG. 2, and this will result in deformation of the fulcrum areas 16 and opening of the jaws 12 and 14 of both gripper heads 10α and 106 simultaneously. When the device 10 is in this condition, illustrated in FIG. 2, a wire 20 may be easily inserted through the region 18 between the jaws 12 and 14 and seated within the line seat 22. Then the fingers may be relaxed to allow the inherent resiliency of the gripper body 10 to restore the operating arms 10c and 10iZ to their normal spaced apart relationship, and the fulcrum areas 16 of each gripper head 10α and 106 will then go from the deformed and stressed condition assumed by them when the jaws 12 and 14 are opened to the relaxed and undeformed normal condition which causes the jaws 12 and 14 of the gripper heads 10 a and 106 to return to their closed position, thus securely clamping the wire 20 within the line seat 22. It will be seen that no great twisting effort is required to engage either of the gripper heads 10α and 106 about the wire 20, as it is only necessary to squeeze the operating arms 10c and lOrf together, slip the wire 20 in place, and release the operating arms 10c and lOrf.

As a further advantageous feature of this invention it will be appreciated that mounting the gripping and spacing device 10 between two parallel wires 20 of a double wire transmission line is equally simple and effortless. As illustrated in FIG. 3 such installation merely requires that the device 10^: be held initially at an angle to the parallel wires 20 as shown by the solid line representation of the gripping and spacing device 10 in FIG. 3. While the device 10 is held in this slanted position, one of the gripper heads 106 may be engaged about the lower wire 20 in the manner previously described. Then, while the jaws of gripper head 106 are engaged about the lower wire 20 and the operating arms 10c and 10d are still held together, the device 10 may be rotated in the direction indicated by arrow 23 to the position illustrated by the phantom lines of FIG. 3 perpendicular to the parallel wires 20 of the transmission line so that the upper gripper head 10α is brought into clamping relationship to the upper wire 29. The lower wire 20 will then slip into the line seat 22 of gripper head 106 as the device 10 approaches the per3,043,902 pendicular position illustrated by the phantom lines of FIG. 3. When the latter position is reached, both wires 20 will be securely inserted within the line seats 22 of the respective gripper heads 10α and 106, at which point the operating arms 10c and lOrf of the device 10 may be released to spring outwardly from each other, causing the jaws 12 and 14 of both gripper heads 10α and 105 to close and clamp both wires 20 within the line seats 22 thereof. It will be readily appreciated -that this operation can be performed with one hand and with one squeezing and one rotating motion. Therefore installation of the device 10 as a spacer between two parallel wires 20 of a transmission line is a very rapidly and easily performed operation, and it is not necessary to exert any unusual twisting force against the resistance of the tightly strung wires 20.

It is an- additional advantageous feature of the linegripping and spacing device 10 of this invention that it can 'be very cheaply and rapidly manufactured in large quantities by means of an extrusion process. An elongated body of the shape exemplified by the segment 10' thereof illustrated in FIG. 4 may be extruded by well-known techniques in the longitudinal direction illustrated by arrow 24, and subsequently a plurality of individual linegripping and spacing devices 10 may be cut therefrom along planes perpendicular to the direction of extrusion, as indicated by the broken lines between the consecutive spacers 10 in FIG. 4.

The novel teachings of this invention of course have broader application than merely to the field of spacing devices. For example it is contemplated that a device which is used merely for the purpose of gripping a single line 20 for the purpose of clamping the line 20 in position or of suspending an object therefrom, may employ only a single gripper head 10α. In addition, numerous modifications of the operating arms 10c and UM may be made, as for example the latter need not necessarily be modeled integrally with the gripper heads 10α or 106, but may be operatively secured thereto in any other manner.

It will now be appreciated that this invention affords a device for gripping a line, or for gripping and spacing a pair of lines, which may be cheaply and rapidly manufactured, and which is very simple to use and install. In addition this device is not subjected to continuous stress of any kind from the line 20 which it is employed to· grip. Thus, if a device of this nature manufactured of a thermoplastic material such as polyethylene were to· be used under conditions of the severest cold, the increased rigidity of the polyethylene material would not make the gripping device subject to breakage, and indeed would only have the effect of making the jaws thereof clamp more securely and tightly about the lines which it is their function to grip.

The particulars of the foregoing description are provided merely for purposes of illustration and are subject to a considerable latitude of modification without departing from the novel teachings disclosed herein. Accordingly, the scope of this invention is intended to be limited only as defined in the appended claims, which should be accorded a breadth of interpretation consistent with this specification.