US1646403A - Lift bridge - Google Patents

Description

Oct' 2.51927' s. HARDESTY ET Ax.

LIFT BRIDGE a Filed' Feb; 17, 1927 2 Sheets-Sheet 2,

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s. HARDESTY ET A1. l

,. LIFT BRIDGE 2 Sheets-Sheet 2 Filed Feb. 1v, 1927 Patented ct. 25, 1927.

Unirse STATES- PATENT oFFicE- u sIioRraIDe-E HAaDEsrY, F L aacHMoNfr, AND WILLIAM G. WILLIAMS, or FLUSHING,

New Yoan, AssIGNoas To WADDELL a HARDESTY, oF NEW YORK, N.v Y., A co- ;PARTNEBSHII ooMPRIsING JOHN A. L. WADDELL AND sHoa'IfRIDeE HARDESTY.

LIFT BRIDGLEQ,A

Application filedvFebruary 17, 192,7,l Serial-N;168,907,-V

The invention aims to provide an improved combination of devices by which power lines are carried to a motor on the moving span and by which the changing stress of the usual counterweight cables is very simply. compensated. Y

The accompanying drawings illustrate an embodiment ofthe invention. o

Fig' 1 is a side elevation of a vertical lift W bridge, party broken away; Fig.- 1a being a detail thereof; l y Fig. 2 is a side ,elevation of part of the apparatus on an enlarged sca-le, the view being taken on the line 2-2 of Fig. 1l;

Fig. a. side'elevation of parts shown in Fig. 2. Y The movable span of the bridge is indicated generally atv1 and the fixed towers at 2. The trusses of the right-hand tower are 2f* broken away at the top to show the parts behind them` more clearly. The weight of the lift span is,,couiiterbalancedfby weights 3 suspended from cables 4 which pass upward over sheaves 5 at the topsA ofthe towers. 25 r1`hey are connected to the counterweights through equalizers 6. Their opposite ends entend downward from the sheaves and are connected `to cross-girders 7 on Vthe ends of the inovingfspan. The span` is lifted and hauledl down by meansA of cables 8A attached to the bottoms andtops of r`the towers, with their bight passing over guide pulleys -9 on the ends of the span and finally over drums 10 at the vcenter which are drivenby suitable motors located in the machinery .house 11 mounted on the top of the span. At the ends of the span are guide shoes 12 which engage suitable vertical guides on the faces ofthe towers. @n the underside at each end of the span are bearing shoes 13 and 14, the former fixed on the pier 15 and the latter being' a rocker pivotally supported on the span so as to allow forilongitudinal movement of expansion. f

Mounted on top ofthe machinery house is rocker 16 in the form of a structural steel bent illustrated in detail in Figs. 2 and 3, supported on hinges 17 at its lower end and carrying' at its upper end circular drums or guides 13. rlhese are provided with spiral grooves shown in Fig. 2 around whichV are wrapped'ropes 19, fixed at one end to a tower and carrying at their opposite ends counterweights 2O below guide sheaves 21 fixed on the tower. As shown in Fig. 1 the left-hand ends of the ropes 19 pass through ysaddles, 22 withv curved bearing faces and arek fastened to supporting blocks 23 on top of the tower. From the saddles 22 th'e ropes 19 leaddownward and wrap around the drums 18 to which they are clamped at one point andare continued around the drum and up tothe guide sheave 21.* Y

kThe power line vor electric conductor 24 is supported `by cleatsor similar devices 25 arranged on the` left-hand portion .of the ropes 19 and passes atits upper end over suitable guides and down alongtheoutside face of the tower as indicated. Before reaching the central drum 18the cable 24 is loosely carried down to the machinery house 11 and into the same. f l

The lift span, counterweights, etc.l are i shown in full linesin the closed position of the bridge and in dotted lines in the open position.` During the operation of the span,

ropes 19 are maintained taut bythe counterweight 20 which alternately falls and rises,

and the bent 16 rocks about its pivot 17 causing the center of guides 18 toniove through the path indicated by the circular dotted line of Fig. 1. Power lines 24, supported by i'opes 19, meanwhile maintain their'connec.-

tionl to the spank with onlyslightchangesof angle at any one point and with a minimum of slackin any of their parts. y'

The vert-ical componentof the pull of the ropes 19Zon the span, acting through bent 16,'

varies from an upward to a downward directioii as. the span rises and passes Athrough a neutral position of no vertical component when'the span isin the half open position. Y

We therefore can constructl counterweight 20 of such weight that these vertical components will balance or compensate for thev unbalanced weight of the main counterweight ropes as they pass from one side to the other of the sheaves 5. The desired compensating effect may be obtained also by` varying' the positions and proportions of the Vseveral parts of the apparatus by which the electrical conductor is carried. And in any case the invention may be advantageously applied to a partial counterbalancing of the variation caused bythe weight of the main counterweight cables, though preferably the parts are designed to secure substantially` complete counterbalancing.

CII

,the motor.

Snot claimed herein, the present application By means of our device therefore we are enabled to dispense with the chains, heavy ropes and other devices commonly used heretofore to balance the variable portion of the main counterweight ropes as well as to maintain direct connection `of the` power lines to the span, without the disadvantages met with in the usev of great hanging loopsv segments l(similar to saddles 22) with straight groovesmaybe used placed one be low the other with their grooves-tangent at their center points.` In either case the ropes are rigidly clamped to the drumor segments at some point of permanent contact fwith it as by clampBOshown in Fig. 3.

Jandvarious other forms offconnection may beiised.

`Saddles 22 on the tower may be dispensed with if swiveled end connections are provided for the attachment ot' ropes `19`to that tower. In the same way ropes 19 may be made in two parts and pivoted end connections to the rocker bent 16 be substituted 'fordrums 18. Y d

f In a co-pending application of Hardesty there is described an arrangementfor balancing thefvariable parts of the main counterweig'ht cables independently of the: scheme ufor vleading the electricalconductors to the motor.; In aseparate application of filliams`,` co-pending herewith,` there is described a scheme Yfor. leading the electrical cables to These separate inventions are being directedto the arrangement bywhich both purposes are accomplished in ayslngle .strii'cture or combinationof parts'- AVarious modificatlons may be made withv l out departing from the invention as defined in the following claims.

Vhatwe claims is:

1. The combination with alift span of a motor carried thereon, a conductor leading from a iixed support to the motor and means for taking up theslack of the conductor as the span moves and 'at the same time coun-` terbalancing loads which vary as the span rises. Y

2. In combination with a lift span carrying a motor, aswinging member carried by 'the span, a conductor leading from a ixed point to the free end of said swinging member and thence to the motor and means attached to the swinging member for swinging the same tomaintain the conductor taut and at the same time to counterbalance loads on the span which vary as it rises.

B. "The combination with a movable span carrying `a motor ot a swinging member carried by said span, a conductor leading from afxed point to the free end of said swinging member and thence to the motor,`

a flexible `connect-ion leading from the swinging member to a ixedpoint of support at theopposite end of tlie'span fromv that which carries the conductor and means for Vtaking up the slack of said flexible connec- "tion and conductor as vthe span rises and for at the `same timecounterbalancing loads on the span vwhich vary as it rises.

4. A `vertical lift bridge span carrying a motor, a swinging member attached thereto7 fixed 'towers at the ends of the span, counterweight,Q for the spancomprising cables leading to overhead pulleys with weights on their free ends7 a cable leading to the swinging member from one tower and from the swinging member over a support on the other tower andv carrying a counterweight `and a conductor leading from one of the towers to the -motor and having its intermediateportion supported by a part of the cable leading to the swinging member. l

`In 'witness whereof, we have hereunto signed our names. i

SHORTRIDGE HARDESTY.

` WVILLIAM G. WILLIAMS.

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