US664391A

US664391A - Turbine water-wheel.

Info

Publication number: US664391A
Application number: US1789A
Authority: US
Inventors: Francis Ellicott
Original assignee: Individual
Current assignee: Individual
Priority date: 1899-09-13
Filing date: 1900-01-17
Publication date: 1900-12-25
Anticipated expiration: 1917-12-25

Description

nu 0 m 5 Z N m e D d e t n e t a P.

F" m 4 6 6 0 N TURBINE WATER WHEEL.

(Application filed Jan. 17, 1900.)

2 Sheatg-Shaet I.

(No Model.)

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- rm! uomus PETERS co., wasmmzrou, 9' c.

No. 664,39l. Patented Dec. 25, 1900. F. ELLICOTT.

TURBINE WATER WHEEL.

(Application filed Jam 17, I900.)

2 Sheets-Sheet 2.

(No Modal.)

44 EanciSEZZiGofl THE NORRIS r'srsns co., wAsmNc-mrv, n. c

NITED STATES PATENT Futon.

. FRANCIS ELLIOOTT, OF BALTIMQRE, MARYLAND.

==r'u RB'INE WATER-WH EEL.-

SPECIFICATION forming part of Letters Patent No. 664,391, dated December 25, 1900. Original application filed September 13, 1899, Serial No. 730,383. Divided and this application filed January 1'], 1900. Serial lie-1,789.

To all whom it may concern.- Be it known that I, FRANCIS ELLICOTT, citizen of the United States of America, and a resident of Baltimore city, in the State of Maryland, have invented certain new and useful Improvements in Turbine Water-Wheels,

of which the following is a specification.

My invention relates to a turbine waterwheel and the peculiar construction of the buckets of the runner and the proportion of these buckets to the inlets; and the object of my invention is to secure high efficiency at any head and any quantity of water. 1

' This application is a division of anapplication filed by me September 13, 1899, Serial No. 730,383.

In the drawings similar characters indicate the same parts in all figures.

Figurelisanexternalelevation of the wheelcasing, partially insection, showing inlets and runner. Fig. 2 is a vertical elevation of the runner removed from the casing. Fig. 3 is a rear view of one of the buckets. Fig. at is a front end View of one of the buckets. is a section of (meet the buckets through the line to a: of Fig. 4. Fig. 6 is a section of the same bucket through the line y y of Fig. 4;. Fig. 7 is a diagram showingthe angle of curvav Fig. 9 is .a front face view of the bucket, and Fig. 10 is a bottom view of the bucket.

Referring to Fig. 1, 1 is a case surrounding therunner and shaft; I

2 2 are water-inlets through the walls of the casing, introduced at an angle so that the inner edge of each inlet shall be approximately tangent to the peripheryof therunner-z'. a,

to a circle described by the external edge of.

the buckets as they revolve. The outer wall of each inlet is tangent to a somewhat smaller circle. e

3 is a cylindrical gate fitting closely into the wheel-casing and suitably connected to a mechanism by which it is raised and lowered to cover more or less of the mouths of the inlets, and thus admit a greater or less quantity of water to the runner. In the vertical side of the inlets 2 2 are grooves 4 4, opposite each other, and in practice I generally employ several sets of these grooves, which are on the same plane, at right angles to the axis of the Fig. 5

Fig. 8 is (Np model.)

runner in all inlets. In these grooves are inthat a higher efficiency can be secured with thesame runner when the water entering the wheel through the inlets is divided and confined on the exterior of the gate than when it is not so confined. opened one-third of the height of the inlet and no dividing-plate be used, the eddy currents. on the exterior of the gate will to some extent destroy the efliciency ofthe water passing through that part of the inlet which is left open by the gate. If the open area of the inlet is circumscribed by the introduction of a dividingplate and the entering water be given more positive direction by-the rigidwalls of the inlet,' which converge directly to the mouth of the portion of the inlet which is open, the impact of the water upon the runner will be more effective and a greater amount of power will be developed. Hence while the water is low and the wheel is running at about one-third gate a higher efficiency can be obtained by the introduction of the dividing-plate such as is shown in this figure. The same is true when the wheel is running with the gate two-thirds open and a second plate is used. If the wheel be constructed to use the average water at full gate, the best results are accomplifiled by locating the groovesin positions corresponding to the proportion'ed decline of the supply, and then shifting the plates from one position to another as the supply fluctuates. The plates, therefore, are made removable, so, that one set of plates-may be used for the wheel, and

they may be. pemoved from one position to another as thd-quantity of water available for the purpose of the'wheel varies, .and this may be done with ease and facility, besides which the presence of a plate in the center of the inlet decreases the area and also acts to catch leaves or other solid matter in .thewater, and thus obstruct the inlet. The grooved inlets and removable plates If the gate be 1898, Serial NO. 680,14t2.

r 6 is a toe mounted on a cross-bar at the" lower end of the casing. 7 is a socket fitting upon it. p i

8 isa main driving-shaft having a flange'i). 10 is a conical hub keyed upon the main driving-shaft 8 and resting upon the flange 9. The hub is conical in form on its exterior andcurved inward, as shown in Fig. 2. To

the surface of the hub 10 is secured a series of buckets 11 ll 11 in the relative positions shown in Fig. 2. The bucket itself is shown in detail in Figs. 3 to 10. The position shown in Fig. 4, which is a frontend view, is the same as the view of the bucket at the center of the runner as it appears in Fig. 2. The bucket has a straight front edge which is parallel to'the axis of the runner and paral-' lel to the interior of the, cylindrical gate; It is sheared on its front edge, as shown in Figs. 5 and 6, so as to present a sharp edge and the least possible resistance to the water entering the inlet when the bucket is opposite the inlet. I The upper portion of the bottom of the bucket--that is to say, of the portion with which the water entering the inlet makes contact when the gate is first opened by lowering is convex. The convexsurfacereferred tois marked 12 in Figs. 4 and 9. It will-also be noticed that the area of the bucket at that point is small and itgradually enlarges toward the lower end of the bucket. The portion of the bottom of the bucket marked 13 in Fig. 4 is concave, and there the. area is much larger than at the point 12. The extreme end of the bucket is bent away from the direction of travel of the runner, and

the end of the bucket is curved almost at a right angle to form an outlet between the curved end and the back of the next following bhcket. i v Refhrring to the diagram Fig. 7, lines a and c d intersect one another at e and are each tangent to the circle 9. fis a circle having the same center as g and a radius equal to that of the runner, while 9 is a circle of calculated radius to which the lines a b and c d are tangent. The radius of gis such as to give to a b and c d the desired angle at e.. a b will represent the inclination of the upper portion eh the bottom of the bucket, as

shown in section in Fig. 5, and c (1 will rep-- resent the inclination of the portion of the. The

made to increase in asomewhat greater ratio than the area of the'inlet -that is to say, the portion of the bottom ofv the bucket opposite a corresponding portion of the inlet above a horizontal plane is greater than the area of the inletand this area increases in a con-- stantly-increasing ratio until the jnaxi num area of the bottom of the bucket is reached.

In the diagram Fig. 7, a I) represent the inclination of the convex surface, and it will will be. perceived that the line a 1) makes, witha tangent to the, circle f at e, an acute angle, which will cause the water to flow toward-thcangle and theedge of the bucket.

The "conical form of the hub serves at this point tocontract the bucket, soils to form a. pocket somewhat proportiuhal in size to the ai'nount of water being admitted. The down- 'ward incline of thebottom-below allows a free escape for the water after it has expended its initial force in impact. Thelower por- I tion of the bucket l3is concave and of much larger area than the upper part, required by the" fact that as the gate'opeus the quantity of-water admitted increases and must be provided for.

The-differences of angle upon which the bottom of the bucket is constructed, as shown in diagram Fig. 7, have been found to be important in order that the maximum efficiency ofa small quantity of water may be secured when the gate is open only about one-third,

in consequence of the water being low. A

maximum efliciency is secured by directing the impact of the inlet-jet at the extreme edge of the bucket. The angle of that portion of the bucket which the water strikes when the gate is nearly closed is therefore made an acute anglewith the tangent to the circle at the outlet, and the water is therefore thrown toward the periphery of the runner and the edge of the bucket, and the full leverage of the radius of the runner is employed. As the inlet is enlarged the quantity of water entering is too great to be utilized in the contracted portion of the bucket, and it is necessary, therefore, to give the bucket a greater. area and also to give discharge direction to the current. This is accomplished by providing thelower part of the bucket with the pocket 13, the curve of which continues to-the discharge end ofthe bucket. As the water enters the upper partof the inlet it will strike upon the concave hub and be deflected downward and outward, and it is desirable to'interpose into the path of this current a resisting-surface. Hence the angle of the bottom of the bucket is changed from the position shown by the lines or b to the position shown by the lines a d, and the. impact of the current as it is deflected fromv the oonical hub outward against the-bottom p the bucket will be availed of to rotate the runner. This action produces-an expenditure of the power of the water in impact and reaction. at the greatestdistance from the axis of the runner, and thereby produces t diliifihect elii- 'right angles to the edge. If they wereextended to a complete right angle, the highest efficiency would result if other elements were in proper relation but 'I have found that a certain law. must be obeyed in construction to secure the highest efficiency. Each bucket being turned at a right angle and curved at its lower end when they are placed on the igo ' opening out of which the water has to flow inlet.

conical hub, there will be a certain area between the bottom of one bucket and the back of the next-that is, the area of the dischargewhen escaping from the runner must be maintained at a certain relation to the area of inlet in order to get the best result. If the area of outlet be less thanthe area of inlet, the inlet-water will be retarded and the chiciency of the wheel will be lowered.

' I have found by calculation and experimentthat the highest efficiency is secured when the lower ends of the buckets are tu rned almost to a right angle and the area ofthe outlet is somewhat greater than :the area of If the wheel be constructed with this relation of area of outlet to inlet at full gate, a lower efficiency will be secured at less than full gate. 1 The efficiency may be raised, however, by readjusting thedividing-plates of the-inlet, so as to make the inlet'a complete one, having. parallel top and bottom for the amount of water. available for the wheel, and

when the water is constant by removing one set of buckets and replacing them by another set the outlets of which bear. the best relation to the inlets.- 'As the areaof outlet is increased in proportion to inlet the amount of water which will pass'through the wheel, and consequently the horse-power of the wheel under constant head, will beincreased; but the efficiency will be lowered. By reducing the diameter of the hubat the lower end to the diameter of the shaft and widening the buckets correspondingly I can increase the area of outlet, which will permit a correspending increase of inlet, and thus acco|n-- cylindrical gate.

the upper portion or inclined at an acute an-' bythe end of the bucketatth-epointot the 1 dial plane-of plish a maximum water capacity and maximum horse-power for a 'givensized wheel. My form of'bucket, therefore, may be stated as being one the exterior edge of which is parallel tothe axis of the runner and to the The bottom is convex at gle with the tangent to the circledescribed edge of the bucket. It is concave at. the

lower portion, or the bottom maybe located at an obtuse angle to; the tangent to the cire cle described by the edge-0f the bucket, and

the bottom is bent at the-lower end in an op posite direction to the moti'onof the runner and trough-shaped at its lowcrwend, the indirection away from the Having described my invention, what I claim, and desire to secure by Letters Patent, 1s r 1'. In a turbine water-wheel, the combination of a casing having water-inlets, a gate and a runner, the runner being provided with a series of buckets, having their outer edges practically straight and parallel to the axis of the runner, the upper portions of their bottoms being convex, the .lower portion concave, and their lower concave ends turned in adirection opposite to the motion of the runner, substantially as described. f

2, In a turbine water-wheel, the combination of a casing having water-inlets, a cylinder gate and runner, the runnerbeing formed with a concave conical hub and a series of buckets attached to the exterior surface of thehub, the outer edges of the bucket being practically straight and parallel to the axis of the runner, the upper portion of their hottoms being-convex, the lower-portionsj'being concave, and their lower concave ends being turned in, a direction opposite the tiq f the runner.-' l

I 3. In a turbine water-wheel, the c01nbinatibn of a casing having water-inlets, a gate and a runner, the runner being provided with a series of buckets havingtheir outer edges practically straight and parallel to the axis of the runner, the upperp'ortions of the bottoms of the ,buckets being convex, the lower por tions concave, and the lower concave end turnedjin a direction almost a'right angle oproe posite to. the direction of the motion of the runner, and 'havingan outlet area slightly greater than the inlet,area, as and for the.

purpose specified. 1 a 4. In a turbine water-wheel the combinaa series of buckets having theig' outer edges practically straight and parallel to the axis of the runner and their bottoms convex at the upper part and concave atthe lower part, these; parts being oppositely inclined to a rathe wheel, substantially as de scribed.

' 5. 'In a turbine water-wheel the combination of a'casing and a water-inlet, a descending cylindrical gate, and a-runnenthe-run- IQS tion of a casing having water-inlets, a gate, Y and a runner, the runner being provided with ner being provided with a series of buckets having their outer edges-practically straight and parallel to the axis'of therunnenthe upper portions of their bottoms being convex, the' lower portions concave, these portions being oppositely inclined to a radial plane of the wheel and having their lowerconcave end turned in a direction oppositeto the motion of the runner. substantially as described.-

Signed byme at Baltimore city State of Maryland, this 12'th day of January, 1900. i FRANCIS ELLICOTT-.- Witnesses:

' CHARLES H. MILLIKIN,

W. W. POWELL.