US1883260A - Suspension clamp - Google Patents

Description

O -18. 1932. w. w. WOODRUFF, 30., ET AL 1,883,260

SUSPENS ION CLAMP Filed Aug. 29, 1927 2 Sheets-Sheet l [III/III l I v I 27. 5 5 a a 5,? W

S 5 w m w mm 0 0 7 Z x WW 0 William W Woodruff'3 wd Raga/2 ATTORNEY Patented Oct. 18, 1932 1,883,260

UNITED STATES PATENT OFFICE WILLIAM W. WOODRUFE, 3D, .01 .SWARTHMORE, AND RALPH JENNER, OF GERMANTOWN, PENNSYLVANIA SUSPENSION CLAMP Application filedjAu-gust 29, 1927. Serial No. 216,146.

Our invention. relates to conductor-supbe varied in proportion, arrangement and porting devices and particularly to suspentexture withoutdeparting from the nature sion clamps for high-voltage transmission and scope of the invention. lines. In suspension clamps for transmission- One object of our invention is to provide line conductors, it has been usual to provide a device of the above-indicated character that channel or other conductor-receiving memshall prevent the imposition of forces on bers with laterally-projecting or disposed adjacent mounting or supporting elements of pivot or other mounting portions, such as the device caused by movement of the line eyes and clevises, for attaching the clamps conductor supported thereby. to insulators.

Another object of our invention is to 'pro- Such a structure, whether it is actually of vide a conductor-supporting device or clamp T-shape in appearance or not, is of T-shape that shall permit oscillations to pass sub in effect, with the part or channel along stantially uninterruptedly through the dewhich the conductor extends constituting vice from one span section of the conductor to the head of the T and the laterally ofiset eye. .1:

another. clevis or other mounting part disposed on Another object of our invention is to prothe leg of the T. vide a conductor clamp that shall substan- When such a structure moves in any directially eliminate crystallization, and the someti-on caused by movement of the conductor, times resultant breaking, of the conductor except in a direction to move the leg of the adjacent to its position of entry to the clamp T directly along its longitudinal axis, there caused by movement of the conductor relaare lateral forces at the outer end of the leg tive to the clamp. of the T which vary in strength in accord- Another object of our invention is to proance with the movement of the conductor,

vide a clamp that shall embody a conductorthe length of the T leg and other factors. 1;. receiving or channel. member, a pivot mount Thus, with the outer end of the leg attached ing element or elements for predetermined to the lower end of a series string of suspenposition relative thereto and mean-s for supsion insulators or to any other structure, porting the element or elements independwhen the conductor oscillates, component ently of, or from a base removed from, the forces of varying frequency and violence are sc portion of the channel member adjacent to transmitted to the insulators, tower or other which the elements are positioned. adjacent parts. This effect sometimes causes Another object of our invention is to prodamage to the insulators and to protective vide a conductor clamp that shall embody devices, such as arcing rings and horns, loosself-releasing clamping means that shall, un- .ening of tower bolts, reactive damage to the s5 der certain conditions, be unaffected but that conductor and other effects, such as strains shall, in response to certain other conditions, in the clamp itself. be affected or permitted to release to alloW Relative to reactive damage to the conducthe conductor to pass therethrough. tor, the clamps are usually provided with Another object of our invention is to pI'O- flared channel ends in an endeavor to reduce 9 vide a clamp that shall be simple and durstrong local or concentrated bending at the able in construction, economical to manufacpositions where the conductor enters and ture and efiective in its operation. leaves the clamp.

With such objects in view, as well as other However, since the conductors are usually advantages which may be incident to the clamped along considerable portions of the utilization of the improvement, the invenlengths thereof, with the above-mentioned tion consists in the parts and combinations T clamp structures, the local bending is only thereof hereinafter set forth and claimed, partially offset by the flared channel ends. with the understanding that the several nec- This is because, with the pivot support latessary elements constituting the same may erally removed from the conductor on the leg of the T, the insulators, tower or other support, by reason of their own inertia and the inertiaof the conductor, oppose free movement of the clamp and there remains a con siderable local bending of the conductor adjacent to the ends of the clamp whether these ends are flared or not.

Also, with the pivot support on the leg of the T, vertical movement of the conductor is necessary to permit the conductor to oscillate.

Further, as set forth in our copending application for a suspension clamp, Serial No. 97,852, filed March 27, 1926, a clamp has been proposed that, under normal line oscillations and the conditions, securely holds the line conductor but that, under abnormal conditions, such as the breaking of the conductor between supporting tov ers, permits the conductor to slip through the clamp. This feature is provided to protect the tower, in sulator and clamp against undue stresses tending to distort, displace and loosen the cooperating parts thereof.

In the device of our copending application, a cam member, that is pivotally mounted on a conductor-receiving member, is directly associated with a supporting or suspension element so that the cam moves therewith in response to ordinary line oscillations or movements, as well as in response to abnormal movement to cause the conductor to slip.

In certain cases, it may be desirable to have the cam move only in response to abnormal movement of the conductor.

In practicing our invention, we provide a conductor-supporting device orclamp in which a conductor-receiving or channel memher and a mounting element or suspension yoke are so relatively movable and related to the conductor as to attain the objects of our invention, as by precluding the institution of lateral forces in the leg of the above-men tioned T, by permitting conductor oscillations to pass substantially uninterruptedly through the clamp and by substantially eliminating the local or concentrated bending of the conductor above referred to. Also, a clamping device is provided that is unaffected by usual vibrations of the line but, that is affected in response to abnormal movement of the conductor, as caused by breaking of the line, to permit the conductor to slide through the clamp.

In order to make the invention more clearly understood, means are shown in the accompanying drawings for carrying the same into practical effect without limitin the improvements in their useful applications to the particular constructions which, forthe purpose of explanation, are made the subject of illustration.

Figure l is a side View, partially in elevation and partially lll section, of a suspei'ision clamp embodying our invention,

Figs. 2 and S are views taken along the lines IIII and IIIIII, respectively, of Fig. 1,

Fig. 4 is a View similar to Fig. 2, of a modified form of our invention,

Fig. 5 is a view, similar structure shown in Fig. gles thereto, and

F i s. 6 and 7 are views, similar to Figs. 2 and 4, of further modified forms of our invention.

Referring to Figs. 1, 2 and 3, the device comprises, in general, a main body or casting in the form of a conductor-receiving or channel member 2 having side walls 3, apertured bosses 4 and recessed portions 5 in the side walls, 8, trunnion 6, and reinforcing webs 7, a liner member 8 for the bottom of the channel in which a conductor or cable 10 rests, a clamping shoe 12 for securing the conductor in position, a liner 1 L, similar to the liner 8, for the clamping surface of the shoe 12, a spring member 15, a cam member 17 and mounting means for all of the above-mentioned parts in the form of a yoke structure 18 that is pivotally associated with the trunnions 6.

The channel member 2 may be of usual form having flared end porti 20 and a portion 21, between the ends 20, that is straight or substantially conforms to the conductor 10 for an appreciable portion of its length to provide effective clamping surfs; l or ween the conductor and the channel member and between the conductor and the clamping shoe 12.

The liners 8 and 14 are preferably of yiel .i able material, such as aluminum, that assist: in gripping the conductor and also, permits it to readily slide or slip through the Cl1 ;1.

The clamping shoe 12 has upwardly-andinwardly curved ends 23 providing not-c or recesses 24 in which the ends of the sprin 15 are received and laterally-extend ci'id projections 25 positioned in the rec es 5.

The ends 23 are also, curved away from the conductor 10, similarly to the ends 20 of the channel member 2, as a precaution against even the slightest crystallization of the conductor adjacent to these ends which, however, in accordance with the main feature of our invention to be hereinafter pointed out, not likely to occur.

The spring 15, preferably of leaf or s 1 steel, is bowed or curved away from the shoe 12 for depression by a cam portion 2'? of the member 17. I

The cam member 17 is pivotally mounted between the bosses 4: on the channel member 2 by a pivot pin 28 that is held in position, as by a cotter pin 29, and further comprises diverging arms 30 fora purpose to be hereinafter set forth.

to Fig. l, of the 4, taken at right an- The trunnions 6, which project outwardly from the channel member 2 at opposite sides thereof, have aligned axes directed substantially through the position occupied by the longitudinal axis of the conductor in the channel.

However, since conductors of slightly varying diameters may be employed with the channel member 2, the axes of the trunnions may be placed at a position to coincide with the axis of one of the conductors or at a position constituting an average or compromise position relative to the slightly varying po sitions of the axes of the different conductors.

Other expedients may, of course, be employed, such as providing a clamp for each conductor of different diameter, with the axes of the trunnions exactly coinciding with the axes of the conductors, or providing adjustable trunnions, it being the spirit and purpose of this invention to have the trunnion axes substantially in a plane of the conductor axis for a purpose to be hereinafter pointed out more at length.

The yoke structure 18 comprises complementary half portions 32 each comprising a bearing portion 33 for one of the trunnions 6, an arm portion 34: and a half socket portion 35 which are separately mountable on the trunnions 6 about a ball-ended pin member 36 and joined by bolt and nut members and 89, respectively. Portions 10 of the halfportions 82, which surround the be t 38, cooperate with the arms 30 of the cam member 17 to operate the latter.

In mounting the conductor in the clamp, the channel member 2 is first placed about the conductor in substantially the relation shown in the drawings and the clamping shoe 12, with the spring on it, placed in the channel on the conductor, with the projections in the recesses or guideways 5.

Next, the cam member 17 is mounted over the spring, between the bosses 4, by the pins 28 and 29.

In so initially mounting the cam member 80, it is turned about the axis of the pin 28 to free the cam portion 27 of the spring 15 which, at this time, is bowed upwardly to its highest position.

Following the aboveanentioned operations, optional methods of clamping the parts may be employed, as by turning the clamping member 80 to the clamping position shown before mounting the yoke structure 18 or by mounting the yoke with the portions 40 between the arms 30 in the unclamped position of the latter and effecting the clamping'action by turning the yoke against one of the arms '30 to the position illustrated in Fig. 1.

In operation, with the pin member 36 con stituting the bottom pin of a series chain or string of suspension insulator units, which is the preferred use of the structure, the parts breaking of the conductor occupy positions substantially as illustrated in Fig. 1.

Grdinarily vibrations or oscillations of the line or conductor 8, between acentsections thereof, cause the channel member 2 and the yoke member 18 to pivot relatively about the axes of the trunnions 6.

Since these axes substantially constitute centers of relative movement between the members 2 and 18 in the center of movement of the conductor 10, there is no undue leverarm movement or lateral-component force transmitted to the yoke 18.

In former devices of this kind, with the trunnions 6 or similar eleinents,ofi center with respect to the conductor 10, either above or below the same, there has been a violent lateral movement of the trunnions 6 against the portions corresponding to the yoke bearing portions 33. The lateral component forces thus instituted have caused strains in the channel body, damage to the insulators and to protective devices, such as arcing rings and horns, and loosening of supporting tower bolts.

Also, since the tower, insulator and offcenter trunnions have opposed free movement of the channel member, as permitted in our device, and, since the conductor is rigidly clamped, there have been node points or points of crystallization of the conductor adjacent to the points of entry and departure of the conductor with respect to the clamp.

The flared ends 14 and 20 are intended to reduce crystallization and concentrated bending forces in the conductor but, with the trunnions 6 ed center with respect to the conductor, the purpose of the flares is only partially accomplished.

In our device, with a wave or oscillation of the conductor approaching the clamp from one side thereof, the clamp will move freely with the wave about the trunnions 6 to permit the wave to pass relatively freely through the clamp without in'iposing appreciable forces on the yoke 18.

Under normal operating condi ions, inc sp cos between the portion to of the yoke 18 and the arms 30 of the cam 18 permit limited free vibration of the channel member 2 with the co ductor and without affecting the clamping forces imposed on the conductor by the shoe 12.

Under abnormal conditions such as the 0 between a cent clan'ips, when the ins to swing through a from its normal vertical position, the portion 410 engages one of the 80 to release the cam portion 27 from the spring 15.

This action releases the clamping force of the shoe 12 on the conductor 10 and permits the latter to slip through the clamp until the side-pulling force on the insulator string is suiiiciently released to permit the latter to oted at a point in the axis of the conductor,

operates with any means for clamping the conductor, such as by the use of U-bolts, J-bolts or any other structure for rigidly or yieldingly clamping the conductor, but it is of particular advantage when employed with the above-described structure whereby the conductor is permitted to slip.

In combination with the center trunnions 6, the feature wherein the portions have lost-motion relation to the arms 30 provides a very effectively operating structure in vhich stresses in, and wear on, the parts are reduced to substantially a minimum and the conductor is protected against damage.

In the above-described structure also, the trunnions (S are shown as constituting integral or homogeneous parts of the channel member 2.

\Vhere the side walls of the cljiannel meniher are thin or where, for any other reason, the forming of the trunnions as integral parts thereof may not be expedient, other methods of mounting the trunnions may be employed, as illustrated in Figs. 4 and 5. The trunnions may also, be mounted in the yoke 18 for cooperation with hearing openings or seats in the channel member 2.

In Figs. 4 and 5, in which corresponding parts are designated by corresponding reference characters, the trunnions 6 constitute parts of a member 42 that is initially formed or manufactured separately from the channel member 2 and subsequently attached thereto by welding or other suitable means.

The member 42 comprises a curved or yoke portion 43 fitted between shoulder portions at the underside of the channel member 2 and constitutes means independent of the channel side walls 8 or having a local base center in the member 2 removed from the trunnions 6 for supporting the latter.

In Figs. 6 and 'Z, in which corresponding parts are also designated by corresponding reference characters, the yoke 18 is constructed as one integrally-Lmited part, instead of being halved or divided, as above described, and the trunnions are supported independently of the channel walls, as in the structure of 4: and 5.

In 6, a relatively thick lower central portion 4-6 is provided on the channel memher 2 and laterally apertured to receive a bolt 47. The bolt 47 supports links 48 and keeper members 50 between which the hearing portions 33 of the yoke 18 are disposed,

the trunnions 6 being partially supported by the links 4 8 and partially supported and maintained in position by the keeper members 50 to which the trunnions are secured. The structure of Fig. 7 is similar to the structure of Fig. 6, with the exception that additional links 52, similar to the links 48, provide additional. strength to the parts. In each of the latter structures, side lugs or shoulders 53, or other suitable means, may be provided on the channel member 2 to prevent the members 48 from turning about the axis of the bolt 47.

By our invention, a clamp is provided that has all of the desirable features of former clamps, such as simplicity and durability, economy of manufacture, ease of assembly facility of installation and other features but that is of materially greater effectiveness in operation, less damaging in its effects on the conductor and other co-operating parts, longer lived and an improvement generally in the service for which it is adapted.

W e claim as our invention:

1. A clamp comprising a conductor-receiving portion, a relatively movable supporting portion therefor and means for clamping the conductor relative to said receiving portion including a cam movable relative to said supporting portion for actuation thereby to release the conductor.

2. A clamp comprising a conductor-receiving channel member, a yoke member pivotally supporting the channel member and means for clamping the conductor in the channel including a member pivotally mounted on the channel member having a clamping cam portion and lost-motion relation to the yoke for operation thereby to release the conductor.

A clamp comprising a conductor-receiving channel member, a yoke member pivotally supporting the channel member, and means for clamping the conductor in the channel including a bowed spring member and a member pivotally mounted on the channel member having cam portion for pressing the spring to clamping position and lostmotion relation to the yoke for operation thereby to release-the spring.

A clamp comprising a conductor-receiving channel member, a yoke member thereabove having free-end bearing portions at opposite sides thereof, trunnions in said hearing portions, links depending from said trunnions, means extending laterally between the channel member and the links, and keeper means on said laterally-entending means for positioning the trunnions.

5. A con ductor-supporting clamp comprising relatively movable clamping members, means including a member for urging said members together and a member normally movable in disengaged relation to said urging member and adaptedto engage the same in response'to predetermined" movement of the conductor to release the latter.

6. A conductor-supporting clamp comprising means to receive the conductor, means including a pivotally-mounted member for clamping; the conductor relative to said receiving means an i a member normally movable in inoporatn'e relation to said clamping means and adapted to operate the same in response to predetermined movement of the conductor to release the latter. 7

7. A conductor-supporting clamp comprising means to receive the conductor, means including a pivotally-mounted member for clamping the conductor relative to said rece ving means and a pivotallymounted member normally movable independently of said clamping means and adapted to operate the same in response to predetermined movement of the conductor to release the latter.

8. A conductor clamp comprising means receive the conductor, a cam for clamping the conductor relative to said means and a member normally movable independently of said cam and adapted to operate the cam in respons to predetermined movement of the conductor to release the conductor.

9. A clamp comprising a conductor-receiving channel member, a cam element pivotally mounted relative to the channel member for clamping the conductor and a clamp-sup porting element pivotally mounted relative to the channel member and movable relative to said cam element, one of said elements having a portion disposed intermediate two portions of the other normally in freely spaced relation thereto for engagement by one of said two portions in response to predeter nincd relative movement of said elements to release the clamping cam.

10. A clamp comprising a conductorreceiving channel member, a cam pivotally mounted between the sides of the channel for clamping the conductor, said cam being of substantially Y-shape, the single lower end of which constitutes the cam clamping portion, and a suspension yoke having its lower free ends pivotally mounted outside the channel 'iember and its upper end constituting supporting means for the clamp, said yoke also having a portion normally disposed between the diverging upper arms of the Y- shaped cam in freely spaced relation thereto for engagement with one of said arms to re lease the cam in response to predetermined ncvement of the conductor.

11. A clamp comprising a suspension yoke of inverted substantially U-shape having mounting means at its cross-connected end and cam-operating means, a conductor-re ceiving channel member pivotally connected between the legs of the U about an axis transverse to the longitudinal channel axis and having side portions projecting upwardly from the sides of the channel, and a clampclamp on one of said members having substantially alined axes transverse to said clamping portions within a space.

of the defined by the outer surfaces cable when the cable is in the clamp, and a suspension yoke including mounting portion and legs at opposite sides of the clamp having pivot elements for cooperation with said first pivot elements, one of the pivot elements at each side of the clamp entirely surrounding its cooperating element for interlocking the clamp and the yoke against separation in any relative position thereof caused by movement of the cable.

13. In combination, a transmission-line clamp comprising means for clamping the line conductor including a conductorreceiving channel member and clamping shoe member having clamping walls for extension along the conductor, trunnions having substantially alined axes extending transversely to said members from one thereof and lispos-ed within a space defined by the adjacent outer limits of the clamping portion of said walls, and a suspension yoke including amounting portion and legs at opposite sides of the clamp having portions thereof entirely surrounding, and constituting pivot bearings for, said trunnions about the pivot axes thereof.

14. The combination with means for supporting a conductor including separate trunnions having aligned axes extending laterally to an axis of said means corresponding to the conductor axis therein substantially in a plane, and at opposite sides of said axis with a portion of said supporting means between them, of means for mounting said supporting means embodying a rigid single- .piece yoke removably associated with said .crunnions.

1 5. A conductor-supporting device com prising a conductor-receiving member, a single-piece, relatively movable yoke member for mounting the same, aligned trunnions extending laterally to said conductor-receiving member at opposite sides thereof and means substantially constituting a second yoke having holding relation to said conductor-receiving member and its free ends connected to the free ends of said first yoke by said trunnions.

16. The combination with means for sup I porting a conductor including a conductor receiving channel member, of means for suspending said member including a yoke, trunnions in the legs of the yoke at opposite sides of the channel having axes extending laterally to the channel axis substantially in a plane thereof, members projecting laterally from the trunnions and substantially constituting continuations of said legs, said projecting members having bolt openings ad jacent to the outer ends thereof, a bolt in said openings, and means for preventing movement of said projecting members about the axis of said bolt.

17. In combination, a conductor-receiving channel member having a transverse opening therethrough below the channel, a singlepiece suspension yoke disposed over said member with the ends of its legs laterally opposite the channel sides, trunnions in said ends having axes extending laterally to the channel axis substantially in a plane there of, link members depending from the trunnions having transverse openings registering with said opening in the channel member, a bolt in said openings, and means for preventing movement of the links about the bolt axis.

18. The combination with means for supporting a conductor including a conductorreceiving channel member, and means for suspending said member including a rigid single-piece yoke member, and separate trunnions associated with the legs of the yoke at opposite sides of the channel extending laterally toward the channel axis substantially in a plane thereof and disposed in fixed relation to one of said members with the channel between them.

' 19. The combination with means for supporting a conductor including a conductorreceiving channel member, of means for suspending said member including a yoke, separate trunnions in the legs of the yoke at opposite sides of the channel with the channel between them and having axes extending transversely to the channel, members projecting laterally from the trunnions, and means for securing said laterally-projecting members to said channel member.

20. The combination with means for supporting a conductor including a conductorreceiving channel member, of means for suspending said member including a rigid single-piece yoke member, a trunnion associated with each side wall of the channel member projecting laterally outwardly therefrom in spaced axially-aligned relation to the other trunnion, supporting means for each of said trunnions connected to the channel member at a position removed laterally from its trunmon.

21. A clamp comprising a conductor receiving portion, a relatively movable supporting portion therefor and means for clamping

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