US1448893A - Pelton-wheel turbine - Google Patents

Description

Mar. 2o, 1923. 1,448,893

. E. WIKI PELTON WHEEL TURBINE Filed Feb. 1l, 1919 ATTORNEY Mar. 20, w23.. 1,443,893

E. WIKI PELTON WHEEL TURBINE @72- BY OQ@ ATTORNEY Cri Fatented Mar. 20, i923.

UNEFFD STATES EDWARD XVIKI, OF LUCERNE, SWITZERLAND.

PELTON-`WHEEL TUB/EINE.

Application filed February 11, 1919. Serial No. 276,286.

To all Iwhom t 'may con-cera:

Be it known that LFnwxnn lV 1in, citizen of the Republic of Switzerland, residing in Lucerne, Canton ot Lucerne, Republic of' Switzerland, have invented a certain new and useful Improvement in Felton-lflheel Turbines, of which the following is atrue and exact description, reference being 'had to the accompanying drawings, which form a part thereo'l. f

My invention relates to free jet turbines ot' the Felton wheel type, and has for its object to provide a construction whereby the loss of power, commonly experienced in such wheels owing to the duty imposed upon the buckets of preventing the loss of the iinpelling fluid in a radial direction is avoided, and at the same time the radial escape of the impelling liuid is efl'ectually prevented. Generally speaking, my invention consists in so forming the buckets, and the casing enclosing them, that there will be no lateral retaining walls either formed on the buckets or by the casing which will prevent the free lateral escape oll the impclling fluid from the buckets, and in providing a satisfactory retaining wall fitting closely to the peripheral edges of the buckets withoutactually coming in contact therewith, and whereby the radial escape of the impelling fluid from the buckets is prevented during the period when it is acting on the buckets.

Reference being now had to the drawings in which my invention is illustrated and in which Figure il is a sidel elevation of the turbine wheel embodying my invention, taken gener.- ally on the line l-l of Figure 2, with the jet nozzle shown in section.

Figure 2 is a cross section on the line 2-2 of Figure l.

Figure 3 is a cross section through a bucket on the line 3 3 of Figure 1.

Figure l is a plan view showing the stationary retaining wall of Figure l, taken as on the section 4.--4 of Figure l, and with the flow ot the water jet indicated thereon, and

Figure 5 is a diagrammatic sectional View illustrating a modification.

A is the pit or well over which the turbine wheel is erected, B, B are supports for the shaft bearing, (l the shaft, D the casing, and E the center ot' the turbine wheel, F, F, etc. are the buckets attached to the wheel center, which, as shown in Figs. l, 2 and 3,

have the usual form of two cylindrical surfaces F, F meeting at an apex F2 and secure-d to the bucket walls by a shank F 3. The buckets are formed without any exterior retaining walls, their outer edges, indicated at F4, having the same outline as the sectional view Fig. 3, said outer edges being turned or ground so that they will coincide with the outline of the cylinder. The inner edges of the buckets are formed with an overhang, as indicated at F5, to prevent the escape of the impelling fluid from the bucket toward the center-of the wheel. The double curvature of the buckets is of importance because the impelling jet striking ron the inner edge of both curves follows the curvature of the bucket in both directions, balancing the thrust on the wheel anl flowtowards the outer edges of the bucket where, in my construction, all of the water leaves the bucket. Gr indicates the nozzle through which the impelling jet, indicated at G, is driven against the buckets of the wheel. H indicates the stationary retaining wall, which, as shown, is supported on or formed as a part of the casing H2, supported on beams 1,1, extending across the pit. The forward edge of this retaining wall is cut away as indicated at H to permit the free entrance of the jet Gr against the buckets without coming in contact with the edge or" the retaining wall H.

ln the modified form of my improved turbine, shown in Fig. 5, I have indicated a structure in which the bucket walls may be cast with the wheel center, and in which the wheel center is provided with a peripheral flange indicated at FA, which with ren gard to the buckets ,indicated at FF, takes the place of and is the equivalent of the overhanging top Harige F5 of the buckets F. ln this construction the retaining wall HH extends all the way around the bucket wheel, the upper portion of it forming a part of the wheel casing.

It will be obvious that owing to the entire absence of exterior retaining walls in my buckets they exert and can exert no power in deflecting the impelling fluid in a direction toward the center of the wheel and that in this waya considerable loss of power is avoided, which loss is incurred in constructions where the bucket wheels are formed with outer retaining walls. At the same time the escape of the impelling 'fluid radially is efectually prevented by the retaining wall HH, which holds the impelling fluid in the buckets against all tendency to radially escape until it has performed the full duty of the bucket and escapes from the sides of the bucket as is: indicated in Fig. 4.

I am aware that in prior designs for water wheels in which side walls are provided to prevent the lateral escape of water from the buckets a wall has been provided to prevent the escape of water from the ends of the buckets until they have moved 4 a certain distance beyond the nozzle. In such designs, however, the water, after imparting a certain amount of its energy to the wheel, is carried with it as a load and finally leaves the buckets with a high velocity, the energy indicated by which velocity is lost as an impelling force. I am also aware that buckets of the general character used by me are old in the lart and are used without side walls but such bucket wheels as heretofore used have not been combined with an end retaining wall such as I show at II and in their use a considerable percentage of water can and does escape over the ends of the buckets before it hasimparted its energy to the wheel. By my construction I have, I believe, for the lfirst time provided for the utilization of the fullenergy of the `iet as an impelling force and avoided the constructive'features of prior wheels which brought about aloss of energy.

Having now described my invention,

what I claim as new and desire to secureby Letters Patent, is:

l. In a free jet turbine of the Pelton wheel type, a buckety wheel having its buckets formed with two curves extending from the center to the edges of the buckets and concave to the jet nozzle, in combination with a casing formedto permit the free escape of fluid over the edges of the buckets,

a jet nozzle arranged to direct impelling fluid against the inner edges of the. concave faces of the buckets, and a stationary fluid retaining wall fitting closely to the unattached ends of the buckets, so as to prevent the escape of fiuid from the buckets otherwise than from the free edges thereof.

2. In a free jet turbine of the Pelton wheel type, a bucket wheel having its buckets formed with two curves extending from the center to the edges of the buckets and concave to the jet nozzle, in combination with a casing formed to permit the free escape of fluid over the edges of the buckets, a jet nozzle arranged to direct impelling fluid against the inner edges of the concave faces of the buckets, and a short stationary fluid retaining wall fitting closely to the unattached ends of the buckets, over an arc immediately in front of the jet nozzle, so as to prevent 'the escape ofl fluid from the buckets otherwise than from the free edges thereof.

3. In a freev jet turbine of the Pelton wheel type, a bucket wheel having buckets curved concavely to the vjet nozzle and arranged with respect to said nozzle so that the jet will strike the receiving edge of the buckets and flow over their concave faces to the other or delivery edges, in combination with a casing formed topermit `the free escape of the fluid over the delivery edges of the buckets, a kjet'nozzle arranged to direct impelling fluid against the receiv ing edges of the buckets' and a stationary fluid retaining wall fitting closely to the outer unattached ends of the buckets so as to prevent the escape of fluid lfrom the buckets otherwise than from the delivery edges thereof.

EDWARDv WIKI.

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