US709316A - System of erecting and adjusting bridge suspension-cables. - Google Patents

Description

Patented Sept. 16,- I902.

r .w. J, GLOVER'. SYSTEM QF EBECTING A ND ADJUSTING BRIDGE SUSPENSION .CABLES.

(A umion filed. A i. 29, 1962.

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UNITED STATES Trice,

WILLIAM JOHN GLOVER, OF ST. HELENS, ENGLAND.

SYSTEM OF ERECTING AND ADJUSTING BRIDGE SUSPENSION-CABLES.

SPECIFICATION forming part of Letters Patent No. 709,316, dated September 16, 190.2.

. Application filed April 29, 1902. Serial No. 105,135. (No model.)

To all whom it nut/y concern.-

Be it known that LWILLIAM JOHN GLovER, engineer, a subject of the King of Great Britain, residing in St. Helens, in the county of Lancaster, England, (whose full postal addressis Liverpool road, St. I-Ielens, aforesaid,) have invented certain new and useful Improvements in Systems of Erecting and Adjusting Bridge Suspension-Cables, (for which application has been made in England under No. 20,739, dated October 16, 1901,) of which the following is a specification.

This invention has for its object a system of erecting and adjusting bridge suspensioncables in such manner as, first, it will not interfere with the traffic beneath; secondly, there will be no occasion to send people along the cables to remove the suspension-clips, and, thirdly, so that the cables already laid shall not be frayed or endangered by the laying of another alongside of them.

In the accompanying drawings, Figure l is a front view illustrating my system for erecting and adjusting bridge Suspender-cables;

Fig. 2, a plan; Fig. 3, side and end views of the two forms of clamp.

I first carry a temporary cable A or traveler across from one terminal suspension-tower B to the other C by boats or other means and pass it over pulleys D, placed about four feet above each saddle E. This temporary cable is then brought down under a guide-pulley F at one end or pier c to a back pulley G, thence several times around a pulley H, worked by a winch I, thence over a second back pulley J, and then undera guide-pulley K to a second pulleyL, arranged about four feet above the saddle E, in line with the first D, thence across the space to be bridged to a similar pulley M, above the other saddle, thence down the tower for some distance to a tension-sheave N and back again to a pulley O on the same shaft as M, thence around guide-pulleys P and back pulleys Q to the other end or pier b. The two ends of the temporary cable A are now spliced and it becomes an endless rope, the slack being taken up when the splicinghas been effected by the winch S. There may be one or two tensionsheaves, if required. These tension-sheaves are drawn down by a block-tackle R, connected with the winch S. a The steam-winch I is now started slowly. At the same time the slack is taken up by the tension-blocks R and subsidiary winch S, tension being applied until-the temporary cable or traveler is sufficiently taut and any superfluous rope is caught up and all strained up. When it is found to run smoothly, a drum containing the first suspender-cable is placed in position and the cable end. secured to the temporary cable or traveler A by means of clamps U, Fig. 3, at a point just above the pulley P. These clamps U are formed of cheeks which grip both the suspender-cable and the traveler A, bolts 25 being employed to fasten the two cheeks together. In the case of a thousandfeet-span bridge, which I expect shortly to lay, the cables, (the travelerA and permanent one,) will be secured together at intervals of about thirty yards by preference with these clamps firmly attached to both cables. The steam-winch now slowly travels the traveler A, pulling the Suspender-cable upward, and as the leading clamp with its suspenderoable approaches the pulley D over saddle E the cable is attached by similar clamps to the forward side of the saddle and clamp on rear side removed. As the traveler hauls up the cable additional running-clamps V are fixed after passing the saddle every twenty yards or so. These clamps V are also formed with a pair of cheeks; but they are so arranged that they are clamped tight to the traveler A only, the permanent cable T passing freely through a hole W, bell-mouthed on each side and of a larger diameter than the cable. As the traveler A arrives at the opposite saddle the first or fixed clamp U is. removed and again refixed after passing the saddle, and the cable is carried down until the prepared end with attachment comes off the drum, this end being secured at X in a bridge-piece by straining-screws. The fixed clamps are kept on and the traveler A is slackened by means of tension-sheave R and WlDGll S until the correct deflection of the permanent cable T is obtained. It is now securely held in position on the saddles by suitable caps and screws. The first fixed clamp and any others which are still fastened are now removed, and the anchor-block and adj listing-screw sleeve are put on and passed into place with the assistance of the power from the steamwinch. When the permanent cable T is finally fixed to the correct deflection and fixed clamps removed, travelerA draws the remaining free clamps V to the saddle, where they are removed, leaving the suspender-cable T free. placing another cable in position in like manner. Itwill also be seen that as the traveler is an endless cable passing twice over the space to be bridged if two of the permanent cables be started from opposite ends they can both be drawn over at same time by the two sides of the temporary cable. The clamps in order to avoid fraying the cables already laid have all their surfaces rounded, and the heads and nuts of the bolts i, clamping the two halves together, are in depressions and do not project beyond the surface of the clamps. The clamps are by preference of brass or copper, so as to lessen the chance of injuring the cable. It is obvious that it is not absolutely necessary to have an endless cable. It could be arranged for the winch to wind up a single length of cable.

Among the advantages of the system are that instead of the permanent cable T hanging slack and being drawn up at heavy strain to its correct deflection it is placed in position first above its correct deflection, and therefore is easily lowered down into position, while at the same time any chance of interfering with the traffic below is avoided. As the clamps V, too, are loose on the permanent cable and can be drawn by the traveler to one pier or the other to be removed, there is no occasion for the very dangerous plan at present adopted of sending men across the place to be bridged in cradles to detach the clamps orclampingdevices,while the arrangement of my clamps is such that there is no chance of injuring the cable.

I declare that what I claim is 1. An apparatus for erecting and adjusting bridge suspension-cables,comprising a length of temporary cable passing over the space to be bridged from one pier to the other, pulleys on the piers and on the suspension-towers over which said temporary cable runs, clamping devices for attaching one end of the suspender-cable to the temporary one, means The traveler A can now be used for.

for driving said cable so that it will act as a traveler and haul the suspender-cable from one pier to the other, and devices for straining up and slacking said temporary cable, whereby the suspender-cable is first placed in position above its correct deflection and can afterward be lowered into position, while at same time any chance of interfering with traffic below is avoided.

2. For erecting and adjusting bridge suspender-cables, a temporary endless cable or traveler passing twice over the space to be bridged, pulleys on the piers and suspensiontowers over which the temporary cable can run smoothly, a winch for driving said cable so that it will act as a traveler to draw the permanent cable over from one end, or from opposite ends at the same time, and tensionsheaves and a subsidiary winch for straining up any superfluous cable and making it taut, and for slackening said temporary cable so as to secure any desired deflection.

3. In apparatus for erecting and adjusting bridge suspender cables, the combination with the traveler of a clamp for securing the suspender-cable thereto, consisting of a pair of cheeks adapted to grip both the cable and the traveler and bolts for binding the two cheeks together, the heads and nuts being in depressions in the cheeks so as not to project beyond the surface of the clamps.

4. In apparatus for erecting and adjusting bridge suspender cables, the combination with the traveler of clamps V for hanging the suspender-cable (at intervals of twenty yards or so) from the traveler, each consisting of a pair of cheeks adapted to grip the traveler only but loose on the permanent cable so that they can be drawn by the traveler to one pier or the other to be removed, whereby there is no'occasion for sendinga man across the place to be bridged in cradles to detach the said clamps.

In witness whereof I have hereunto signed my name, this 18th day of April, 1902, in the presence of two subscribing witnesses.

WILLIAM JOHN GLOVER.

\Vitnesses:

G. O. DYMOND, F. P. EVANS.

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