US1810053A - Suspension clamp - Google Patents
Suspension clamp Download PDFInfo
- Publication number
- US1810053A US1810053A US234374A US23437427A US1810053A US 1810053 A US1810053 A US 1810053A US 234374 A US234374 A US 234374A US 23437427 A US23437427 A US 23437427A US 1810053 A US1810053 A US 1810053A
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- United States
- Prior art keywords
- conductor
- clamping
- clamp
- ball
- loop
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G7/00—Overhead installations of electric lines or cables
- H02G7/05—Suspension arrangements or devices for electric cables or lines
- H02G7/053—Suspension clamps and clips for electric overhead lines not suspended to a supporting wire
Definitions
- My invention relates to conductor clamps and particularly to suspension clamps for supporting highvoltage transmission-line conductors.
- One object of myinvention is to provide a clamp, of the above-indicated character, that shall materially reduce the mechanical stresses resulting therein and in the adjacent insulator and tower parts, from oscillations of the conductor supported thereby.
- Another object of my invention is to provide a clamp that shall embody substantially universally, relatively movable clamping and supporting elements.
- Another object of my invention is. to provide a conductor clamp that shall so embody a spring clamping element and a ball for holding the spring in clamping condition as to reduce friction between the spring and ball and to permit them to have desirable and effective relative movement without reducing the clamping forces exerted bythe spring.
- Another object of my invention 1s to provide a conductor clamp in which parts shall so universally move about a point on the axis of the conductor, as it would normally extend in similar clamps, as to compensate for vibrations in substantiallv all directions of movement of the conductor.
- Another object of my invention is to provide a clamp embodying parts, normally adapted to be positively heldin clamping relation and to assume relatively loose released relation, that shall be so interlinked as to permit free relative movement of the parts in the clamped condition thereof and to prevent separation of thejparts in the released.
- a further, object of my invention is to provide a clamp that shall be simple and durable in construction, economical to manufactme and effective in its operation.
- clamps such as those embodying U-bolts, J- bolts and the like, for rigidly and permanently holding the conductors in'place.
- the point 1 about which the parts universally move is laterally offset from the conductor axis and the clamp is not adapted to automatically release the conductor under any conditions likely to occur in service.
- Fig. 2 isa view, partially in elevationv and partially in section, taken along the line II-II of Fig. 1;
- Fig. ,3 is a View, similar to Fig. 1, of a modified form of my invention.
- Fig. 4 is a View, similar to Fig. 2, of the structure shown in Fig. 3.
- the clamp comprises, in general, a lower conductor-re- 2 This movement is cenceiving or clamping member 2 for the reception 0 a conductor 3, an upper clamping or shoe member 4 and a supporting or suspension element 5.
- the lower clamping or channel member 2 comprises oppositely disposed aligned flared end portions 7 and an intermediate substantially half-tubular body portion 8 that constitutes a continuation of the end portions 7 and is displaced laterally upwardly from the axes of the portions 7.
- the member 2 also comprises a depending loop portion 9, upwardly projecting side lugs 10 and a cen-, tral seat portion 12.
- the upper clamping shoe or member 4 is provided with flared end portions 14, opposite the end portions 7 of the lower member 2,. a half-tubular body portion 15, substantially conforming to the laterally offset por tion 8 of the lower member 2, side portions 17 of inverted substantially cup-shape telescopically fitted over the lugs 10 of the lower member 2, and lugs or projections 18 for supporting and securing the ends of a leaf spring 20.
- the supporting or suspension element 5 is substantially in the form of a yoke having an upper portion 22 of any suitable form, such as a socket, for attachment to the lower end of a suspension insulator string (not shown), and depending side leg portions 23 having apertured lower end portions 24 for the reception of a block or seat member 25 and a pin 26 that extends through the portions 24 and 25 and is held in position, as by a cotter pin 27.
- the seat member 25 is provided with an arcuate upper seat portion 29 for the reception of a ball-bearing member 30 which may similarly cooperate with an arcuate seat surface on the seat portion 12 or, as shown, the seat portion 12 may be provided with 'an aperture for the reception of a body 32 for rigidly securing the ball member 30 to the seat portion 12.
- the body 32 may be in the form of a screw cooperating between the ball 30 and the seat portion 12 or, as shown, may constitute a body of material welded in position to the ball member 30 and to the seat portion 12, such constructions being merely sug gestive of any suitable means for positioning the bell.
- the spring member 20 supports a cam member 34 having an upper surface 35 that, in the clamping condition of the parts, is spherically curved about the center of the ball 30 and extends along the conductor from each side of its center, in the normal vertical condition of the suspension element 5, for about thirty degrees and for a certain distance lateral to, or about, the conductor
- a second ball member 38 is loosely secured in the upper central portion of the yoke 5, as by overhanging lips 39,- to cooperate with the surface 35 to compress the spring 20 and thereby transmit clamping forces between the clamping members 2 and 4 through the yoke 5.
- the loop portion 9, at the under side. of the under clamping member 2, aermits the above-mentioned universal movement of the clamping members on the block member25 and guards against separation of the clamping members from the suspension element or yoke structure.
- a cam bearing surface 45, on the shoem-emher '4, is provided with a slightly depressed accentuating portion 46 for the normal cen,
- structure 7 llO line breaks or the yoke 5 is otherwise caused to move angularly a sufficient distance about the center of the ball 30.
- the body 32 for securing the ball 30 in position cooperates with the lower clamping member 2 instead of the upper clamping member 4.
- the lower end of the yoke 5 is integral with the side legs 28, and the upper portion 22 is removably secured in position, as by a main pin and a cotter pin 51.
- the portion 22 is fitted between inwardly extending lugs 52, at the upper ends of the side legs 23 of the yoke 53, whereby it may be held rigidly in position, by the single bolt 50.
- clamping members 2 and 4 and associated parts may be moved universally about the center of the ball 30 through limited relative distances, the spaced relation of the lugs 48 to the lug 49 permitting such movement,
- the lug 49 engages one of the lugs 4-8 to move the roller 43 off the surface 45 into one of depressions 54 at the side thereof to release the clamping members and the conductor.
- the clamping efiect depends upon the inherent yieldability of the conductor 23 and play between the other parts but may be augmented or adjusted by the addition of further yieldable means, the omission of play between the parts or other suitable expedient.
- a suspension element having a portion of substantially loop-shape, an elongated conductor receiving element extending through, and supported by, the loop portion in relatively movable relation tom thereof, said conductor-receiving element being arched at its mid portion, and bearing means between said elements beneath, and. adjacent to, the crown of said arched portion.
- a suspension element having a portion of substantially loop-shape, an elongated conductorreceiving element extending through, and supported by, the loop portion inrelatively movable relation thereto, adjacent to the bottomthereof, said conductor-receiving element being arched at its mid portion and having portions projecting from ends of the arch at an angle thereto, and bearing means between said elements within aspace bounded by the arch and a straight'line between said ends.
- a suspension element having a port1on of substan-- tially loop.shape, an elongated conductorreceiving element extending through, and supportedby, the 'loop portion in relatively movable relation thereto, tom thereof, said conductor-receiving element being arched at its mid portion, and substantially ball-and-socket bearing means between said elements beneath, and adjacent to, the crown of said arched portions.
- a suspension element having a portion of substantially loop-shape, an elongated conductor-receiving element through, and'supported by, portion in relatively movable relation thereto, adjacent to the bottom thereof, said conductor-receiving element being arched at its mid portion, bearing means between said elements beneaththe crown of said arched-portion, and an inverted substantially arched portion on said conductor-receiving element and exthereto, adjacent to the botadjacent to the botthe loop tending between points at opposite sides of said bearing means around theunder side of the latter.
- a suspension element having a portion of substantially loop-shape, an elongated conductor-receiving element extending through, and supported by,
- said conductor-receiving element being arched at its mid portion, bearing means between said elements beneath, and adjacent to, the
- conductor-receiving channel elements for normally holding the conductor in predetermined position and responsive to apredetermined movement of the conductor to release the conductor.
- a suspension element havin an upper mounting por tion and a lower portion of substantially loopshape, and an elongated conductor-receiving element extending tl1rough,and supported by, the loop element in relatively movable relation thereto, and an inverted substantially arched portion: on said, conductorereceiving element and extending between points at opposite sides of said suspension loop portion around the under side of the latter.
- an elongated eonductor-receiving member in relatively movable relation thereto about a given point, and means on, and cooperating with, said conductor-receiving member to constitute substantially loop in eccentric relation to said point about said supporting member and having the greater part of its perimeter spaced substantially from said supporting member.
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- Insulators (AREA)
Description
- June 16, 1931. F. H. MILLER 1,810,053
SUSPENSION CLAMP Filed Nov. 19, 1927 2 Sheets-Sheet l INVENTOR Frederic /7i/7/7/e/r B 7 ATTORNEY June 16, 1931. F. H. MILLER 1,810,053
I SUSPENSION CLAMP Filed Nov. 19, 1927 2 Sheets-Sheet. 2
ATTdRNEY Patented June 16, 1931 neura srars arser ea FEEDER/l0 H. MILLER, 0F WILKINSBURG, PENNSYLVANIA, ASSIGNOR T0 WESTING- HOUSE ELECTRIC 6 MANUFACTURING COMPANY, A CORPORATION VANIA 0F PENNSYL- SUSPENSION' CLAMP Application filed November 19,1927. Serial No. 234,374.
My invention relates to conductor clamps and particularly to suspension clamps for supporting highvoltage transmission-line conductors.
One object of myinvention is to provide a clamp, of the above-indicated character, that shall materially reduce the mechanical stresses resulting therein and in the adjacent insulator and tower parts, from oscillations of the conductor supported thereby.
Another object of my invention is to provide a clamp that shall embody substantially universally, relatively movable clamping and supporting elements.
Another object of my invention is. to provide a conductor clamp that shall so embody a spring clamping element and a ball for holding the spring in clamping condition as to reduce friction between the spring and ball and to permit them to have desirable and effective relative movement without reducing the clamping forces exerted bythe spring.
Another object of my invention 1s to provide a conductor clamp in which parts shall so universally move about a point on the axis of the conductor, as it would normally extend in similar clamps, as to compensate for vibrations in substantiallv all directions of movement of the conductor.
Another object of my invention is to provide a clamp embodying parts, normally adapted to be positively heldin clamping relation and to assume relatively loose released relation, that shall be so interlinked as to permit free relative movement of the parts in the clamped condition thereof and to prevent separation of thejparts in the released.
condition thereof.
A further, object of my invention is to provide a clamp that shall be simple and durable in construction, economical to manufactme and effective in its operation.
Heretofore, in high-voltage transmissionline practice, it has been usual to employ clamps, such as those embodying U-bolts, J- bolts and the like, for rigidly and permanently holding the conductors in'place.
It has also been recently suggested to employ clamps known as slip clamps, whereby, in response'to predetermined line conditions,
such as breaking of the conductors, the con ductors are permitted to slip through the clamps to prevent undue stresses in the clamps, insulators and tower parts. I a A clamp of still different type has been suggested in which a limited universal relative movement is permitted between the clamping members and a suspension element therefor.
However, in the latter clamp, the point 1 about which the parts universally move is laterally offset from the conductor axis and the clamp is not adapted to automatically release the conductor under any conditions likely to occur in service.
It is my aim to provide a transmission -line clamp that shall embody certain features of the clamps heretofore employed, but that shall also embody features Which shall render it an improvement thereover, particularly with reference to the above-mentioned clamp in wlnch a certaln universal movementis permltted.
Accordingly, 1n practlclng my invention,
I provide a supporting or suspension ele- Figure 1 of the accompanying drawings is aside view, partially in elevationand par-, tially in section, of a clamp constructed in accordance with my invention; I
Fig. 2 isa view, partially in elevationv and partially in section, taken along the line II-II of Fig. 1;
Fig. ,3 is a View, similar to Fig. 1, of a modified form of my invention; and.
Fig. 4 is a View, similar to Fig. 2, of the structure shown in Fig. 3. I
Referring to Figs. 1 and 2, the clamp comprises, in general, a lower conductor-re- 2 This movement is cenceiving or clamping member 2 for the reception 0 a conductor 3, an upper clamping or shoe member 4 and a supporting or suspension element 5.
The lower clamping or channel member 2 comprises oppositely disposed aligned flared end portions 7 and an intermediate substantially half-tubular body portion 8 that constitutes a continuation of the end portions 7 and is displaced laterally upwardly from the axes of the portions 7. The member 2 also comprises a depending loop portion 9, upwardly projecting side lugs 10 and a cen-, tral seat portion 12.
The upper clamping shoe or member 4 is provided with flared end portions 14, opposite the end portions 7 of the lower member 2,. a half-tubular body portion 15, substantially conforming to the laterally offset por tion 8 of the lower member 2, side portions 17 of inverted substantially cup-shape telescopically fitted over the lugs 10 of the lower member 2, and lugs or projections 18 for supporting and securing the ends of a leaf spring 20.
The supporting or suspension element 5 is substantially in the form of a yoke having an upper portion 22 of any suitable form, such as a socket, for attachment to the lower end of a suspension insulator string (not shown), and depending side leg portions 23 having apertured lower end portions 24 for the reception of a block or seat member 25 and a pin 26 that extends through the portions 24 and 25 and is held in position, as by a cotter pin 27.
The seat member 25 is provided with an arcuate upper seat portion 29 for the reception of a ball-bearing member 30 which may similarly cooperate with an arcuate seat surface on the seat portion 12 or, as shown, the seat portion 12 may be provided with 'an aperture for the reception of a body 32 for rigidly securing the ball member 30 to the seat portion 12. The body 32 may be in the form of a screw cooperating between the ball 30 and the seat portion 12 or, as shown, may constitute a body of material welded in position to the ball member 30 and to the seat portion 12, such constructions being merely sug gestive of any suitable means for positioning the bell. I
The spring member 20 supports a cam member 34 having an upper surface 35 that, in the clamping condition of the parts, is spherically curved about the center of the ball 30 and extends along the conductor from each side of its center, in the normal vertical condition of the suspension element 5, for about thirty degrees and for a certain distance lateral to, or about, the conductor A second ball member 38 is loosely secured in the upper central portion of the yoke 5, as by overhanging lips 39,- to cooperate with the surface 35 to compress the spring 20 and thereby transmit clamping forces between the clamping members 2 and 4 through the yoke 5.
The parts are shown in the normal operating positions which they assume when the line conductor 3 is stationary, under which condition, the ball 38 is at the center of the surface 35 on the cam member 34.
In response to limited torsional or twisting movement of the conductor 3', all of the parts associated with the clamping members 2 and 4, as distinguished from the yoke 5' and its associated parts, move laterally a limited distance in either direction, while the ball 38 remains on the surface 35 to sustain the clamping forces of the spring 20. Also, under normal longitudinal oscillations of the conductor, the ball 30' similarly remains on the surface 35 and rides back and forth'thereon, without diminishing the clamping forces.
However, when, in response to breakage of the conductor orother cause, the yoke memher 5 moves angular-1y relative to the clamping members 2 and 4 a sufiicient distance to the right the ball 38 rides off the surface35 to permit the release of the spring 20 and, consequently, the release of the clamping members 2 and 4 and of the conductor 3.
The loop portion 9, at the under side. of the under clamping member 2, aermits the above-mentioned universal movement of the clamping members on the block member25 and guards against separation of the clamping members from the suspension element or yoke structure.
Referring to the modification of my invention shown in Figs. 3 and 4, in which corresponding parts are designated by corresponding reference characters, the and operation are similar, except that the spring 20 is omit ed and the clampingforces are transmitted directly between the clamping members 2 and 4 through a cam member 40 that is supported by upwardly-projecting side portions 41 of the clamping member 2.
Also, instead of the lugs 10 and the cup portions 17 on the members 2 and 4, respectively, which are provided to prevent longitudinal displacement of the members 2 and 4, accidental disassembly of the clamping members is prevented by a loop portion 42 on the shoe 4, which interlinks a roller or cam portion 43 that is heldin position, at the lower end of the cam member 40, by a pin 44.
A cam bearing surface 45, on the shoem-emher '4, is provided with a slightly depressed accentuating portion 46 for the normal cen,
tral clamping position of the roller 43 which does not normally ride on the surface 45,.
does the ball member 38 on the surface'35- of the above-described structure, but remains stationary under normal line conditions and is only movedout of this position. when the or to the left, as viewed in Fig, 1,
structure 7 llO line breaks or the yoke 5 is otherwise caused to move angularly a sufficient distance about the center of the ball 30.
The above-mentioned operation is permitted by diverging lugs 48 on the cam member which are disposed in spaced relation at opposite sides of a depending centrallug 49'on the portion 22 and are engaged by the lug 49 only under abnormal conditions, as above set forth.
In this form also, the body 32 for securing the ball 30 in position cooperates with the lower clamping member 2 instead of the upper clamping member 4.
Also, instead of the removable block 25 at the lower end of the yoke 5, as in the structure shown in Figs. 1 and 2, the lower end of the yoke 5,'in this form of my invention, is integral with the side legs 28, and the upper portion 22 is removably secured in position, as by a main pin and a cotter pin 51.
The portion 22 is fitted between inwardly extending lugs 52, at the upper ends of the side legs 23 of the yoke 53, whereby it may be held rigidly in position, by the single bolt 50.
Under normal line-operating conditions, the clamping members 2 and 4 and associated parts may be moved universally about the center of the ball 30 through limited relative distances, the spaced relation of the lugs 48 to the lug 49 permitting such movement,
However, when the yoke member 5 moves a suflicient distance, about the center of the ball 30, to the right or to the left, as viewed in Fig. 3, the lug 49 engages one of the lugs 4-8 to move the roller 43 off the surface 45 into one of depressions 54 at the side thereof to release the clamping members and the conductor.
In the form of my invention shown in Figs. 3 and 4, the clamping efiect depends upon the inherent yieldability of the conductor 23 and play between the other parts but may be augmented or adjusted by the addition of further yieldable means, the omission of play between the parts or other suitable expedient.
In both forms of my invention, above set forth, having the center of universal movement substantially on an axis that would be the longitudinal axis clamp having a straight conductor seat, prevents the transmission of lateral-component vibrating stresses in any direction between the clamping members and the yoke. Thus,
, the effects are avoided that usually obtain in ordinary clamps to loosen insulator pins, tower bolts and other parts, and it is contem plated that, in addition to its advantages per se or-within the clamp itself, the use of the invention may result in material economy in tower construction, as well as render the installation more permanent and effective in operation.
While I lar forms of my invention, changes may be of the conductor in a have shown and described particueffected therein without departing from the spirit and scope thereof, as set forth in'the appended claims.
I claim as my invention:
1. In a line-conductorsupport, a suspension element having a portion of substantially loop-shape, an elongated conductor receiving element extending through, and supported by, the loop portion in relatively movable relation tom thereof, said conductor-receiving element being arched at its mid portion, and bearing means between said elements beneath, and. adjacent to, the crown of said arched portion.
2. In a line-conductor support,v a suspension element having a portion of substantially loop-shape, an elongated conductorreceiving element extending through, and supported by, the loop portion inrelatively movable relation thereto, adjacent to the bottomthereof, said conductor-receiving element being arched at its mid portion and having portions projecting from ends of the arch at an angle thereto, and bearing means between said elements within aspace bounded by the arch and a straight'line between said ends.
3. In a line-conductor support, a suspension element having a port1on of substan-- tially loop.shape, an elongated conductorreceiving element extending through, and supportedby, the 'loop portion in relatively movable relation thereto, tom thereof, said conductor-receiving element being arched at its mid portion, and substantially ball-and-socket bearing means between said elements beneath, and adjacent to, the crown of said arched portions.
4. In a line-conductor support, a suspension element having a portion of substantially loop-shape, an elongated conductor-receiving element through, and'supported by, portion in relatively movable relation thereto, adjacent to the bottom thereof, said conductor-receiving element being arched at its mid portion, bearing means between said elements beneaththe crown of said arched-portion, and an inverted substantially arched portion on said conductor-receiving element and exthereto, adjacent to the botadjacent to the botthe loop tending between points at opposite sides of said bearing means around theunder side of the latter. 7
'5. In a line-conductor support, a suspension element having a portion of substantially loop-shape, an elongated conductor-receiving element extending through, and supported by,
the loop portion in relatively movable relation thereto, adjacent to the bottom thereof,
said conductor-receiving element being arched at its mid portion, bearing means between said elements beneath, and adjacent to, the
conductor-receiving channel elements for normally holding the conductor in predetermined position and responsive to apredetermined movement of the conductor to release the conductor.
6. In a line-conductor support, a suspension element havin an upper mounting por tion and a lower portion of substantially loopshape, and an elongated conductor-receiving element extending tl1rough,and supported by, the loop element in relatively movable relation thereto, and an inverted substantially arched portion: on said, conductorereceiving element and extending between points at opposite sides of said suspension loop portion around the under side of the latter.
7. In a line-conductor support, an elongated eonductor-receiving member, a member for supporting the same at an intermediate portion thereof in relatively movable relation thereto about a given point, and means on, and cooperating with, said conductor-receiving member to constitute substantially loop in eccentric relation to said point about said supporting member and having the greater part of its perimeter spaced substantially from said supporting member.
8. In a line-conductor,support, a suspension element of substantially loop-shape, an elongated, conductor-receiving channel element extending through, and supported by, the loop element in relatively movable relation thereto, adjacent to the bottom thereof, in spaced relation to the upright sides of the loop element, said conductor-receiving element being arched at its mid portion and having portions projecting from the ends of the arohat an angle thereto, substantially balland-socket bearing means between said elements Within a space bounded by the arch and a straight line between said ends, and means cooperating between said suspension-loop and conductor-receiving channel elements for normally h oldin the conductor in predetermined position and responsive to a predetermined movement of the conductor to release the conductor. V
In testimony whereof, I havehereunto subscribed my name this 10th day of November,
FREDERIO H. MILLER.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US234374A US1810053A (en) | 1927-11-19 | 1927-11-19 | Suspension clamp |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US234374A US1810053A (en) | 1927-11-19 | 1927-11-19 | Suspension clamp |
Publications (1)
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US1810053A true US1810053A (en) | 1931-06-16 |
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Application Number | Title | Priority Date | Filing Date |
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US234374A Expired - Lifetime US1810053A (en) | 1927-11-19 | 1927-11-19 | Suspension clamp |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2811413A (en) * | 1953-05-20 | 1957-10-29 | Thomas S Mcmillan | Fluorination process |
-
1927
- 1927-11-19 US US234374A patent/US1810053A/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2811413A (en) * | 1953-05-20 | 1957-10-29 | Thomas S Mcmillan | Fluorination process |
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