US2106006A

US2106006A - Cable supporting device

Info

Publication number: US2106006A
Application number: US92756A
Authority: US
Inventors: Charles H Klein
Original assignee: National Telephone Supply Co
Current assignee: National Telephone Supply Co
Priority date: 1936-07-27
Filing date: 1936-07-27
Publication date: 1938-01-18
Anticipated expiration: 1955-01-18

Description

Jan. 18, 1938.

C. H. KLEIN CABLE SUPPORT-INC: DEVICE Filed July 27, 1936 INVENTOR.

Patented Jan. 18, 1938 UNITED STATES PATENT QFFIQE.

The National Telephone Supply Company,

Cleveland, Ohio, a corporation of Ohio Application July 27, 1936, Serial No. 92,756

3 Claims.

This invention relates, as indicated, to cable supporting devices, but has reference more particularly to a device for suspending electrical transmission cables from a messenger strand which is firmly attached to poles placed at intervals along a transmission line.

It has heretofore been the practice to support aerial telephone, telegraph or power transmission cables by means of circular rings of a diameter l0 considerably in excess of the cable diameter, such rings being supported by yoke-shaped devices which are secured to the messenger strand at spaced intervals.

It has been observed that cables suspended in this manner have, after varying periods of time,

shown signs of wear, such as cutting and cracking where supported by the first rings on each side of the poles to which the messenger strand is attached. The cutting or abrasion of the :9 sheath of the cable is caused by the swing and twisting or torquing of the free hanging cable supported in rings, which near the pole, are not free to swing or torque. This sets up a relative sliding movement between the rings and cable resulting in wear of the softer cable by the harder surface of the ring. This of course permits the entrance of moisture into the cable with resultant circuit troubles.

It has been further determined that the abrasion and cutting is aggravated by the fact that the rings are rather sharply curved in their lower or supporting portions so that the cable, in its rolling action, can not roll up the side of the ring, due to action of gravity, and therefore rolls against the side of the ring in its attempt to climb, thus setting up an abrasive action, which is aggravated by the dust which is normally deposited on the cable and rings in field construction.

This invention has as its primary object the provision of a cable-supporting device for cables of the character described, through the use of which cutting and abrasion of the cable sheath, incidental to the lateral, longitudinal and twisting movements, is reduced to a minimum.

To the accomplishment of the foregoing and related ends, the invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawing and the following description setting forth in detail certain structure embodying the inventign, such disclosed structure constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawing:

Fig. 1 is a side elevation of a fragment of a cable and the supporting means therefor; Fig. 2 is a view of the cable supporting device as viewed from the right of Fig. 1; Fig. 3 is a View of the end of the yoke opposite to that shown in Fig. 2; and Fig. 4 is a top plan View of the yoke.

Referring more particularly to the drawing, there is disclosed a messenger strand I, which is firmly attached to poles (not shown) spaced at different intervals along the transmission line. Secured to this strand at suitably spaced intervals are yokes 2 having ends adapted to tightly grip the messenger strand, these yokes being similar to that described in Gherardi Patent No.

1,336,558. The bar 3 of the yoke is bent upwardly intermediate its ends as at 4 for a purpose which will be presently described.

Mounted on the bar 3 of the yoke is a hanger 5 for supporting the cable 6. One end of the cable supporting hanger 5 is attached to the bar by means of a substantially closed loop 1, in the form of an eye, whereas the other end of the hanger is attached to the bar by means of a pigtail eye 8, so that it can be snapped on to the bar after the closed eye 6 has been threaded onto the bar.

The yoke 2 may be made of round or fiat wire and the hanger 5 is preferably made of wire of generally rectangular cross-section, the wire in each case being galvanized after forming to increase its resistance tocorrosion. The hanger is of somewhat pear-shaped contour, and that portion 9 of the hanger which lies immediately below the cable and is subtended by the angle included within lines l0, I0 is in the form of an arc having as its center the axis ll about which the hanger swings during the lateral swinging movements of the cable.

Due to this construction of the hanger 5, the cable in its lateral swinging movement will not move in the hanger but the cable and hanger will move as a unit around the axis II, which is at the top of the cross bar 3 of the yoke. If the cable is subject to torque without swinging action, it will roll along the bottom of the hanger Without change in its altitude, but the hanger will move from side to side about the above mentioned axis of the yoke cross bar. Also, when the cable moves longitudinally due to temperature changes or to vibrations set up by heavy traffic on highways or railways, the hanger will slide on its aforementioned yoke cross bar and so reduce longitudinal movement between cable and hanger.

Although I have described these features sepiii arately, it is understood that they hold true if more than one action takes place at one and the same time. Moreover, the curvature of the side portions [2 of the hanger adjoining the ends of the portion 9 is relatively sharp as compared with the curvature of a circular hanger of a size comparable to the present hanger, but the curvature is such that cables of both the minimum and maximum diameter carried by the hanger will make instant, whole line contact with the cable when any abnormal swinging movements of the ring occur, such as are sufficient to cause the cable to engage these side portions. In this way, the cable .will be prevented from riding up on such side portions to any extent and the abrasive effects thereof avoided. The portion 9 of the hanger may be of any desired length, but in practice, it has been found that this portion of the hanger need not exceed in length the diameter of the cable which is to be supported by the hangers.

The kink or bend 4 in the cross-bar of the yoke serves to prevent the ends of the hanger from being drawn together and the hanger collapsing when the cable is drawn through the hanger. In the absence ofa stop member as formed by the bend A, the ends of the hanger might be drawn together along the yoke cross-bar, eventually making contact and resulting in a distortion of the hanger which will not permit free passage of the cable.

It may be further noted that if the yoke crossbar is of circular cross-section and the eyes 'i' and 8 only slightly larger in diameter than the cross-bar, the bar would act like a shaft in its bearings, which bearings, if not lubricated, would create enough friction to partially offset the ad vantages resulting from the above described features. Obviously such bearings cannot be lubricated in practice. I therefore make the top portions of the eyes I and 3 substantially flat so that the hanger will roll on the yoke bar in the same manner that the cable rolls on the bottom of the hangers. The bar engaging portions of the eyes are, as shown in Fig. 2, actually in the form of arcs of circles struck from substantially the center of the cable-supporting portion 9 of the hanger.

It is thus seen that a cable supporting hanger has been provided, through the use of which abrasion and cutting of the cable is reduced to a minimum.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the structure herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:-

1. A device of the character described comprising a cable supporting hanger having a lower portion of substantial length in the form :otan are having as its center the axis about which said hanger swings incidental to swinging movements of the cable supported thereby.

2. A device of the character described comprising a cable supporting hanger having a lower part of substantial length in the form of an are having as its center the axis about which said hanger swings incidental to swinging movements of the cable supported thereby and adjoining. portions of relatively sharp curvature which is substantially the curvature of the cable carried in the hanger. v

3. A device of the character described comprising a cable supporting hanger having a lower portion in the form of an arc the center of which lies in the axis about which said hanger swings during swinging movement of the cable supported thereby, said portion being of a length approximating the diameter of the cable to be supported by said hanger.

CHARLES H. KLEIN.