US2335327A - Wicket - Google Patents

Description

Nov. 30, 1943.

C. M. WELLONS WICKET Filed NOV. 10, 1941 4 shams-sheet 1 l fallin Chan-les M. Ue/lons Ill. Il

Nov. 30, 1943.v c. M. WELLQNSy WICKET Filed Nov. lO, 1941 I 4 Sheets-Sheet 2 p/f E rndlL-En a Nawal Y fr L A w 7.. 1 4 2 ad A .n d 001 7.

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WICKET Filed Nov. 1o, 1,941 4 sheets-sheet 4 "char/s M. wer/ons Patented Nov. 30, 1943 WIOKET Charles M. Wellons, Bellevue, Pa. Application November 10, 1941, Serial No. 418,492

(Cl. lil-27) ('Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) Claims.

The invention described herein may be manuiactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a method and means for operating wicket dams and particularly to an improved wicket for use with such dams, adapted to be raised or lowered by mechanical power.

Wicket dams, in present practice, are operated by means of a maneuver boat which travels along the raised section of the dam and raises or lowers the wickets successively. The wickets are raised or ltripped by the pull on a wire line supplied by a steam hoisting engine mounted on the boat. The operator, by means of a long-handled hook, must hook the line to the butt of the wicket when raising or to the head when lowering the dam. The manual operations require a considerable degree of skill with wickets of the height used on the existing dams. With greater wicket heights and consequently greater depth of water and higher velocity, these operations become impracticable. Operation by maneuver boat involves considerable risk to the operating personnel under favorable conditions, and is particularly hazardous in 'damp weather or when heavy ice has formed on the pools. 'I'his invention provides a means for operating wickets by mechanical means from a gallery within the dam, thus eliminating the manual labor and risk as well as the limitation in the height of wickets due to operating difliculties.

The operation of my improved wicket mechanism will be clear from a consideration of the following description taken in conjunction with the accompanying drawings in which- Fig. 1 is a longitudinal section showing the raising device mounted in the mass of the dam in relation to the wicket;

Fig. 2 shows a downstream view of the wicket with the raised portion of the plunger indicated by dotted lines;

Fig. 3 is a downstream view showing the link of the wicket;

Fig. 4 is a view partly in cross-section of a preferred form of construction of the plunger and guide;

Fig. 5 is a mechanism chart showing successive posi-tions of the wicket horse and link in process of raising or lowering;

Fig. 6 is a longitudinal section showing the tripping device mounted in relation to the wicket and the mass structure of the dam;

Fig. 7 is a downstream view showing the link and crank of the trip mechanism mounted in relation to the wicket;

Fig. 8 shows an alternate mechanism for actuating the plunger, utilizing a worm gear and screw; Fig. 9 is `a horizontal view, partly in crosssection, showing the worm and worm wheel indicated in Fig. 8;

Fig. 10 shows another alternate device for operating the plunger, utilizing spur gearing;

Fig. 11 is a view at righ-t angles to the device shown in Fig. l0 illustrating the relations of the gears; and

Figs. 12, 13 and 14 illustrate three methods of operating wicket dams using power operated wickets and show the relation of the gates and wickets at various stages.

Referring to Figs. 1, 2 and 3, numeral represents the wicket to which the horse 2 and link 3 are connected by means of pivot pins 4D and 4l. The other ends are attached to the mass of the dam structure by means of pivot pins I6 and 43. The apparatus as thus described is similar in its principle of operation to the wicket gate described in Patent No. 1,120,787, granted to G. B. Bebout, December 15, 1914.

When the resultant of the water pressure on the face of the wicket falls a suicient distance below the horse hinge 4, the wicket remains'in the raised position. When the position ofthe resultant rises because of a rise in the level of head water or tail water or both, or when the differential between the two levels is suiiiciently reduced, the wicket falls.

From Fig. 5 it will be evident that certain points in the body of the wicket I follow along lines that do not deviate widely from a straight line as the wicket is raised or lowered. Such a point is represented in this ligure by letter A. The letter B represents the hinge 4, and the letter C the pin 4|.

In order to utilize a simple rod and plunger mechanism, the plunger 5 is placed in the mass of the dam and arranged to move in a straight line approximating the path of the selected point A. A roller 6 is mounted on the wicket atvthe selected point with its axis normal to the plane of motion and forms a bearing surface wherebyV its rim may make contact with the top of the plunger 5 throughout the line of travel.

Referring to Figs. 1 and 4, it will be seen that the plunger 5 operates in a chamber l that is inclosed in the mass of the dam below the still level. It is actuated by hydraulic pressure applied within the chamber. A removable guide 8 secured to the top of the chamber serves to guide the plunger 5 and to contain the packing 9 and a wiper I0. When it is desired to raise the wicket, pressure is admitted to the chamber l through inlet valve Il. Tov lower the plunger 5, the outlet vvalve I2 is operated while the inlet valve Il remains closed. The weight of the plunger to gether with the pressure of the tail water on its head effects the downward movement. Ordinarily, the plunger would be lowered after the wicket has been raised and the pool level 'estab-V which may be used in conjunction with the device described above and which serves to trip the l wicket when the pool levels are below the tripping stage. In the operation of such dams,.it is some` times desirable or necessary to draw waterfrom the storage retained by the wickets or to lower the' head water level. I'he wicket, as described above, will not fall until the tail water or head water has risen to the tripping stage. To trip the wicket at lowered stages, some additional means are needed.

In the preferred form, this embodiment of the invention -consists of the wicket I, the horse 2, and link 3, which are identical as described before. A linkage mechanism consisting of a link I3 is attached to the wicket I by the pins I4 and I5 at a point above the horse hinge 4. A bell crank I'l is mounted to rotate about its center upon the pin I6, and connected to the link I3 by means of the pin 22, all being arranged so that the link I3 is substantially parallel to the horse 2. A roller i3 is mounted upon the lower arm of the bell crank I'I and acts as a bearing surface. A plunger I9 operates in a chamber 2E] constructed within the foundation structure, the said plunger being capable of movement in a line more or less tangential to the arc of movement of the roller I8. A removable guide 2| secured to the top of the chamber 23 serves to guide the plunger and contain the packing and wiper.

When fluid pressure is admitted to the chamber 20 through the inlet valve 23, the plunger I9 is forced upward, causing the link I 3 to exert a force upon the wicket at its `point of connection at I4. This force'produces a moment about the horse hinge 4 which overcomes the opposing moment of the water load about the same point and causes the wicket to fall.

In cases where hydraulic power is not readily available, it may be desirable to usev the alternative form illustrated in Figs. 8 and 9 for raising or lowering the plunger 5. In these figures, the lower end of the plunger 5 is provided with a threaded portion 24. A ring gear 25 is provided with internal threads 32 adapted to coact with the threaded portion 24 of the plunger 5. The circumference of the gear 25 is toothed to coact with worm gear 23 which is turned in bearings Z'I from the power source 28. A guide member 29 is rigidly attached to the lowerrnost end of the plunger 5 vand is provided with slots adapted to slide in guides 3!) lplaced in the casing 3! and prevent rotation of the plunger 5. Counterclockwise rotation transmitted to the worm gear 2G causes a clockwise rotation of the ring gear 25 which causes an upward movement of the plunger 5 through the cooperation of threaded surfaces 25 and32. To lower the plunger 5, a reverse rotation is imparted to the worm gear 26. v

A second alternative form of raising or lowering the plunger 5 is illustrated in Figs. 10 and 1l.

In these figures, the lower end of the plunger 5 is provided with a rack portion 33. A shaft 34 is mounted for rotation in bearings 35 and carries rigidly attached thereto spur gears 36 and 3l. Spur gear 3B is adapted to drive the rack v33 while spur gear 31 is adapted to be driven by Spur gear 38, which in turn, is driven by the power source 39. A clockwise rotation impartedto the spur gear 38 impartsa counterclockwise rotation to spurgears 35 and 31. This rotation of spur gear 36 imparts an upward motion to the plunger 5 through the rack 33. To lower the plunger 5, a reverse rotation is imparted to the spur gear 33.

It appears obvious that either of the arrangements illustrated in Figs. 8 or 10 is equally well adapted to operate the tripping plunger i3.

v The obj ect of using power operated high wickets is to provide a navigable pass in a navigation dam with a lift that is greater than is practicable for ping stage.

wickets of the type now used.

Wickets are held in the raised position by the force of the water against the upstream face. 'I'.he moment of this force opposes the tripping moment due to the weight of the wicket and determines whether the wicket will stand or fall.

The moment exerted by the water load is determined by the net head acting on the wicket and by the arm of its application about the horse hinge il. Tripping may therefore result from reduction of either the moment arm, or the force, or the reduction of both together.

Three basic conditions of pool stage will cause tripping.- rIhese are rise of the upper pool, rise of the lower pool, and loss of stage differential between the upper and lower pools. The rst two raise the position 0i the resultant of the water pressure and reduce the moment arm while the latter will cause tripping irrespective of the position resultant.

These considerations make possible several plans for the construction of darns with navigable passes composed of high lift wickets. Three plans are shown on Figs. 12;, 13 and 14. The relative merits of these plans are dependent on a number of considerations in respect to design and operationv of the darn and control of the river.

Pla-ns based upon rise of the pool above the top of the wicketsy involve such objections that theyare not considered. However, overtopping at high stages insures a positive tripping moment since under this condition the head acts with the weight to throw the wicket.

In all plans, it is proposed to provide suihcient controlled weir area to pass the flow of the trip- For this purpose, gates 35 are preferred. Where the width of river available does not permit the use of sufficient gated area without `encroachment on the width needed for the navigable pass, power tripped wickets are proposed to make up the necessary controlled area.

It isv important that the pool storage be released gradually, For relatively long and deep pools, this is more important than for the presentV dams. Sudden release of the storage above l the natural stage corresponding to the tripping stage would cause a sudden rise below and would cause excessive current above and below the lock.

Referring to Fig. 12, when there is no iiow, the gates i5 are kept closed and the wickets raised, as shown in IE6.. But sometime before the normal tripping stage is reached, the plungers 5 are raised. As the flow starts, the gates i5 are gradually raised and the conditions of the pools are as shown in Fig. 12b. Upon an increase in flow greater than can be handled by the gates 35, the plungers 5 are lowered successively as shown in Fig. 12c allowing the wickets` i to fall, gradually increasing the discharge area until the pools are about equalized, after which the remainder of the pass can be opened without delay. The effect on the pools would be substantially the same as in the present method of operation of wicket dams except for the greater volume of storageto be released.

Referring to Fig. 13, the lower pool with no flow is shown in Fig. 13a. Under these conditions, the gates l5 would be kept down and the wickets I raised. At a iiow less than ythe tripping stage, the gates d are gradually raised and water flows into the lower pool raising the level of that stage as shown in Fig. 13b. The wickets are constructed so that successive groups automatically trip at successively higher levels of the lower pool. As the iiow increases, the rst group of wickets will fall lowering the upper pool and raising the lower pool as shown in Fig. 13e. Further rise trips the second group and so on until the last group of wickets falls from loss of head as shown in Fig. 13d.

In Fig. 14, sufficient control of area is provided to pass the tripping stage with a small head, say about two feet. The wicket mechanism is proportioned so that the moment of its weight will overcome the moment of the water load at this head. The condition of the dam with normal pools at no flow is shown in Fig. 14a. With the flow less than the normal tripping stage, the gates 45 are gradually raised as shown in Fig. 14h. As the flow approaches the tripping stage, the gates are raised to a suicient height to draw down the upper pool and raise the lower pool as shown in Fig. 14e. As the differential between the upper and lower stages decreases, the wickets fall for lack of supporting head as shown in Fig. 14d. If at any time the head should be made too great to allow the wickets to fall at the tripping stage, the further rise in the level would decrease the arm of its moment and insure tripping at a somewhat higher stage.

This plan has the advantage of disposing of the bulk of the storage in the pool before the tripping stage is reached, thus avoiding the possbility of an objectionable Wave in the river. In addition, it permits the use of wickets that have a high degree of stability as long as they are retaining the pool and not excessively overtopped. The plungers would be used only for raising the dam and would remain protected at all other times. Except for raising ,the pass wickets, operation would be confined to the controlled weir.

While I have described my invention in conjunction with a preferred embodiment of my invention, it is to be understood that I do not wish to be limited to the particular arrangements and assemblies shown since obvious modifications within the scope of my invention will suggest themselves to one skilled in the art.

Having described my invention what I claim as new and wish to secure by Letters Patent is:

1. In a dam, the combination of a self-tripping wicket mounted upon a sill structure, said wicket comprising a body member, a link pivoted adjacent the lower end of said body member, the other end of said link being pivoted to said sill structure, and a brace having one end pivotally attached to said sill and the other end pivotally attached adjacent to and below the center of said body member, a bearing surface on said wicket and a power-operated plunger substantially inclosed within said sill structure and arranged to have a substantially vertical movement whereby a force may be exerted upon said bearing surface to raise said wicket, said plunger being free to be withdrawn leaving said wicket in its raised selftripping position.

2. A mechanism for raising self-tripping wickets mounted upon a sill structure, said wicket comprising a body member, a link pivoted adjacent the lower end of said body member, the other end of said link being pivoted to said sill structure, and a brace having one end pivotally attached to said sill and the other end pivotally attached adjacent to and below the center of said body member, said mechanism comprising a cylinder, a separable power-operated plunger in said cylinder, said plunger having a substantially vertical reciprocating movement, and a bearing surface on said wicket arranged to contact said plunger, said bearing surface having a substantially vertical path as said wicket is raised.

3. In a dam, a self-tripping wicket mounted upon a fixed sill structure, said wicket comprising .a body member, a link pivoted adjacent the lower end of said body member, the other end of said link being pivoted to said sill structure, and a brace having one end pivotally attached to said sill and the other end pivotally attached adjacent to and below the center of said body member, a cylinder embedded in said sill structure and substantially flush with the surface thereof, a separable power-operated plunger arranged for vertical reciprocating movement within said cylinder, said plunger being entirely within said cylinder at its lowermost position and extending substantially above said sill structure at its highest position, and a bearing surface on said wicket arranged to be contacted by said plunger, said bearing surface placed on said Wicket at a point having a substantially vertical path as said wicket is raised.

4. In a dam the level of which is to be regulated, the combination of a self-tripping wicket mounted upon a sill structure, said wicket including a body member, a link pivoted adjacent the lower end of said body member, the other end of said link being pivoted to said sill structure, and a brace having one end pivotally attached adjacent to and below the center of said body member, the other end of said brace being pivotally attached to said sill structure, said link and brace being disposed in such a manner that in the absence of any external force said body member will remain in its raised position until the level of the impounded water passes a predetermined depth, a bearing on said body member at a point which follows a substantially vertical path as said body member is raised or falls, a power-'actuated piston within said sill structure, the upper end of said piston coacting with but unattached to said bearing to raise said wicket whereby said wicket may be held against the hydrostatic forces tending to trip the wicket or left in self-tripping position.

5, The combination according to claim 4 including, in addition, a second link pivotally attached to said body member at a point above said brace and below the center of said body member, the other end of said last-mentioned link being pivotally attached to one arm of a bell crank, said bell crank being pivotally attached to said sill, and a second power-actuated plunger within said sill structure arranged to engage a bearing on the other arm of said bell crank, said lastmentioned link and crank being disposed in such a manner that when said crank bearing is raised by said second plunger the hydrostatic forces tending to maintain said wicket in its raised position will be overcome and said wicket will fall.

CHARLES M. WELLONS.

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