US2081611A - Turbine - Google Patents

Description

E. WESTMA-N 2,081,611

TURBINE Filed. Jam. 15, 1936 -4 Sheets-Sheet 1 v as E. WESTMAN TURBINE Filed Jan. 15, 1936-" 4 Sheets-Sheet 3 E. WESTMAN May 25, 1937.

TURBINE I,

4 Sheets-Sheet 4 Filed Jan. 15, 1936 Patented May 25, 1937 Nl'lEl) STATES PATENT OFFICE TURBINE Emil Westman,

Excelsior, Minn,

assignor of 5 Claims.

My present invention relates to turbines and more particularly to steam-actuated turbines of the impulse-reaction type, and generally stated, has for its object to simplify the construction and increase the efficiency generally of turbines.

Steam turbines of the prior art quite generally comprise a casing, a rotating barrel or drum therein, vanes on the drum, and co-operating fixed or relatively fixed vanes on the interior of the casing. In these prior arrangements there is very considerable clearance between the fixed vanes of the casing and the moving vanes of the barrel and between the drum and the casing and, as a result, much of the high pressure steam passes the turbine without direct action on the moving vanes. With the old arrangement, therefore, there has been a waste of steam energy due to the fact that all of the steam (or other motive fluid for that matter) is not so confined and directed as to act with maximum efficiency on the moving vanes, and hence, upon the. rotor.

My invention very greatly modifies the above noted older structure and provides an arrangement wherein all of the steam or motive fluid delivered into the casing is caused to act directly upon the moving vanes of the rotor; and where the motive fluid is an expansible fluid, such as steam, the steam will act on the moving vanes, first, by impulse or impact; second, by reaction; and third, more or less by expansion. In this way high efficiency is obtained and no steam is permitted to pass without direct action on the moving vanes.

As a highly important feature my invention provides a reversible turbine wherein the reverse action is obtained, not by adjustments of the vanes, but by a reversely oblique arrangement of concentric series of inner and outer vanes on the rotor; by co-operating concentric rows of nozzle passages in a nozzle plate; and co-operating series of concentric ports in a rotatively adjustable valve plate.

The valve plate works in rotative contact with the nozzle plate so that there is no escape of steam or motive fluid between the two; and the rotor and its vanes work in such close face to face contact with the nozzle plate that there is no chance of escape of steam or motive fiuid between the two and all of the steam or motive fluid is caused to directly act upon the moving vanes of the rotor.

The novel features above outlined will more fully appear in connection with the drawings which illustrate a simple form of the turbine,

, wherein but one disc-like vane-equipped rotor is provided and wherein like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is an elevation looking at what is here considered as the front side of the turbine;

Fig. 2 is a view corresponding to Fig. 1 but with some parts sectioned, some parts broken away, and with the front head of the casing and outside attached parts removed;

Fig. 3 is a vertical section taken through the turbine on the line 33 of Fig. 1

Fig. 4 is a section on the same line as Fig. 3, but with parts broken away and with the interior mechanism of the turbine removed from the casing;

Fig. 5 is a fragmentary section taken on the line 5-5 of Fig. 3;

Fig. 6 is a fragmentary section taken on the line 6--6 of Fig. 3;

Fig. '7 is a face view'of the disc-like rotor, the vanes thereof being indicated partly in full and partly by dotted lines;

Fig. 8 is a section taken on the curved line 8-8 of Fig. 2;

Fig. 9 is a section taken on the curved line 9-9 of Fig. 2;

Fig. 10 is an enlarged fragmentary elevation showing a portion of the vane-equipped rotor;

Figs. 11, 12, 13, and 14 are fragmentary views in section taken respectively on the lines I|-l I,

l2|2, 13-43, and I4--|4 of Fig. 10;

Fig. 15 is a perspective showing one of the impelling vanes removed from the rotor;

Fig. 16 is a view in elevation, with some parts broken away, looking at the outer face of the valve plate; and

Figs. 1'7, 18, 19, and 20 are views corresponding to Fig. 16 but illustrating different positions of the valve plate.

As will most clearly appear by inspection of Figs. 1, 3, and 4, the casing of the turbine here illustrated is made up of an internally cylindrical member 2| and heads 22 and 23, which ele ments are connected with steam-tight joints and are secured together by machine screws 24. The cylindrical member 21 is formed with anchoring lugs 25 and with steam admission and exhaust ports 26 and 21, see particularly Figs. 1, 2, and 4, and which ports are formed with laterally projecting bosses to which, respectively, steam admission and exhaust pipes 28 and 29 are coupled, a fine mesh wire screen 30, as shown, being interposed between steam pipe 28' and ports 26, as best shown in Fig. 2. Steam pipe 28 is shown as provided with suitable valve 3i by means of which the supply of steam maybe turned on or cut off. 32 indicates a normally closed oil cup which, in the particular structure illustrated, leads to the port 26. Cylinder 2i is formed with an internal annular flange 33 to which, as will presently appear, a nozzle plate of novel construction is applied.

Head 22 is provided with a long axial sleeve 34 best shown in Fig. 3; and head 23 is provided with an axially projecting hub-like sleeve 35. Head 22, as shown, is further provided with a segmental internal flange 35, the minor purpose of which will hereinafter appear.

Mounted in the sleeve 34 is a bearing bushing 31 that is free for axial adjustments but is held against rotation in said sleeve by a key 38, see particularly Figs. 3 and 5. When bushing 31 has been properly adjusted, it may be locked against axial movements by suitable means such as a screw 39, shown in Fig. 5, and which screw works through the sleeve 34 and is adapted to be tightened against said key. Axial adjustments of the bushing 3'! when screw 39 is loosened is arranged to be accomplished by a cap nut 40 that has threaded engagement with the outer end of said bushing and is swivelled to the outer end of the sleeve 34 by means of screws 4! that work with threaded engagement through the outer end of the sleeve 34 with their inner ends engaged with an annular groove 42 cut in the exterior of the telescoped portion of the cap nut 40, see Figs. 3 and 6.

The numeral 43 indicates a grease cup, the threaded delivery stem of which is screwed into a hole in the top of the sleeve 34 and is adapted to deliver grease to theexterior of the bushing 31 through a grease passage 44 formed in the latter.

A nozzle plate of disc-like form and of novel construction is secured to the internal flange 43 of the cylinder 21, and as the turbine illustrated is a reversible turbine, this nozzle plate is preferably made up of concentric rings 45 and 46. The outer ring 45 is. shown as directly secured to the flange 33 by screws 41 and the inner ring 46 is shown as secured to the outer ring by screws 48. -By reference to Fig. 3 it will be noted that the ring 45 is flanged and set against the flange 33 and that the inner ring 46 is flanged and set into the outer ring 45, so that the lefthand faces of the two rings 45 and 45, as viewed in Fig. 3, are flush and present a perfectly flat continuous surface. Also it will be noted that the right-hand faces of the rings 45 and 46 are flush with each other and with the right-hand face of the flange 33 so that they present a perfectly flat continuous right-hand face. The flush and flat face arrangement of said elements 45 and 45 is of the utmost importance, as will presently appear.

Attention is now directed particularly to Figs. 2, 3, 8, and 9. The outer ring 45 of the nozzle plate is provided with a plurality of circumferentially spaced nozzle passages 45a of which, as shown, there are eight; and the ring 45 is provided with circumferentially spaced nozzle passages 46a of which, as shown, there are eight. As best illustrated in Figs. 8 and 9, the nozzle passages 45a and 46a are oblique in opposite directions, that is, the passages 45 are oblique for delivery of steam in a counterclockwise direction, and the passages 45 are oblique for the delivery of steam in a clockwise direction in respect to Figs. 1 and 2.

The rotor-of this motor is in the form of a fiat faced disc or plate 49 that rotates between the flange 3t and the nozzle plate made up of.

the rings 45 and 46 and works close to and nearly but preferably not quite in actual contact with the adjacent face of the said nozzle plate. This rotor is secured to the inner end of a power shaft 55 that extends through and is journaled in the bushing 31 and cap 40.

Attention is now particularly directed to Figs. 3 and '7 to 15, inclusive, which illustrate the peculiar and novel structure of the rotor. Before describing the elements of this rotor in detail, it may be stated that the same is provided with an outer concentric row of vanes (sometimes because of their concave structure called buckets) and with a similar but reversely ar ranged inner series of vanes, the outer vanes being arranged to run past and receive the steam blasts from the. nozzle passages 45a, and the outer vanes to run past and receive the steam blasts from the reversely directed nozzle passages 45a. This reverse arrangement of the nozzle passages and of the vanes provides a reversible turbine, that is, a turbine in which the rotor is adapted to be rotated in either direction at will simply by directing the steam or motive fluid through one or the other of the reversely inclined or oblique nozzle passages.

The rotor here employed involves, per se, novel features of construction. As best shown in Fig. 10, this rotor in addition to the vanes, includes three concentric elements, to wit: a hub flange 5|, an outer ring 52, and an intermediate ring 53, all of which elements are of the same width and are aligned so that their side surfaces will lie in the same planes. The vanes themselves are of peculiar and novel construction and have concavo-convex body portions 54, rectangular outer end heads 55 and half width base ends 56. The heads 55 of the outer row of vanes are assembled in aligned contact against the interior of the outer ring 52, while the heads of the inner vanes are likewise assembled against the inner surface of the intermediate ring 53. The ring 53 is notched to receive the reduced ends 56 of the outer series of vanes, and the hub flange 5| is likewise notched to receive the inner ends 56 of the inner row or series of vanes.

By reference to Figs. 11-12 and Figs. 13-14, it will be seen that the vanes are assembled in reverse order in the inner and outer series, the arrangement, therefore, being such that the nozzle passages 450. will discharge into the concave sides of the upper series of vanes, and the nozzle passages 450, will discharge in a reverse direction into the concave faces of the inner vanes. Also, it is highly important to note that the heads and inner ends and concave body portions of the vanes are of the same width as the rotor elements 5!, 52, and 53, so that the complete rotor has a common maximum transverse width, and the vanes, as well as the concentric elements 5|, 52, and 53 will run nearly but not quite in complete contact with the adjacent face of the nozzle plate, thereby preventing the escape of steam or motive fluid, except against the vanes.

The next and highly important element of this turbine is the valve plate, which, as preferably designed, is in the form of a disc 5'! having a concave hub 58 journaled on an axial hub 59 of the nozzle plate, see particularly Fig. 3. The flat right-hand face of this valve plate, as viewed in Fig. 3, works in close axial contact with the adjacent flat face of the nozzle plate and, as shown, it is spring-pressed into this engagement by a coiled spring seated in the inner end of a rock shaft 6|, the enlarged inner end or head of which is shown as provided with diametrically opposite dowel pins 62 that engage seats in the hub 58.

The head on the inner end of shaft 61 limits its outward movement so that spring 60 finds a base of reaction for pressing the valve plate against the nozzle plate. The reduced end of shaft 6| works through a suitable thrust bearing 63 mounted in the hub 35 of head plate 23. As a means for oscillating the shaft 6| and hence the valve plate, a flanged collar 64 is shown as rigidly secured to the outer end of said shaft -6l, and this collar is pinned or otherwise secured to a sleeve 65 journaled on a reduced portion of the hub 35. To sleeve 65 is secured an operating handle or lever 66 which carries a pointer 61 that works over a graduated indicator plate 68 secured to the hub 35. Obviously, the dowel pins 62 cause the valve plate to be oscillated with the shaft 6| and hence with the lever 66.

I will now consider the novel arrangement of controlling ports in the oscillatory valve plate. For co-operation with the outer circular series of nozzle passages 45a of the nozzle plate, the valve plate 5'! is provided with a circumferentially extended row of ports 10d, and 16b; and for cooperation with the inner annular series of nozzle passages 46a, said valve plate is provided with an inner concentric row of circumferentially spaced ports Na and Mb.

The relative arrangement of said ports just noted can best be made clear by following the different positions of the valve plate illustrated in Figs. 16 to 20, inclusive. Fig. 16 shows the valve plate in normal position, that is, with all the ports closed and the turbine idle, in which position the lever 66 will stand in the neutral position best shown in Fig. 1. When lever 66 is moved toward the left in respect to Fig. 1, until its pointer 61 is aligned with the left-hand numeral 4 on the indicator plate 68, the valve plate will be then set as shown in Fig. 17 and the four ports 160. will then be opened, and this will start rotation of the rotor in a counter-clockwise direction in respect to Figs. 1, 2 and 16 to 20, inclusive. If higher speed or greater power is required, the lever 66 is moved farther toward the left until its indicator 6'! is aligned with the left-hand numeral 8 on the indicator strip 68; and this movement of the valve plate will close the ports 10a, but will open up the eight ports 10b, thereby giving the increased power and speed by the additional or more rapid supply of steam or motive fluid. This last noted position of the valve plate is indicated-in Fig. 18.

For reverse direction of rotation of the rotor, lever 66 will be moved first toward the right until its pointer 6! is aligned with the right-hand numeral 4 on the indicator plate 68, and this will position the valve plate as shown in Fig. 10, thereby opening up the four ports 1la. This will start the rotation of the rotor in the clockwise direction in respect to the drawings noted. When still greater speed or power is required for the rotation in the clockwise direction, lever 66 will be moved toward the right until its pointer 61 is aligned with the right-hand numeral 8 on the indicator plate 68, and this will set the valve plate in the position shown in Fig. 20, thereby closing the ports 1 la and opening up the eight ports 'Hb.

As already pointed out, in the zero position of lever 66 and normal or initial position of the valve plate, all of the valve ports will be closed. It is also evident that in all of the positions of the valve plate for rotation of the rotor in one direction, the ports of the valve plate for rotation in the opposite direction, will remain closed. Attention is also further called to the fact that the ports 10a of the outer series, and the ports Fl la, of the inner series are so positioned that only four thereof at any one time will be brought into registration with co-operating nozzle passages 45a or 46a, but that the ports 10b of the outer series and the ports 1 lbof the inner series are so positioned that eight thereof at any one time can be brought into registration with the co-operating 8 nozzle passages. Of course, the number of the said nozzle passages can be varied, in which case the ports in the valve plate would have to be correspondingly varied.

The arrangement illustrated and described has, in practice, been found highly efficient both for obtaining variable power and variable speed. In practice, the rotor of the turbine in which the invention is incorporated, has been driven at a speed as high as thirty-five thousand revolutions per minute.

Means for setting the rotor for rotation nearly but preferably not quite in actual contact with the adjacent face of the nozzle plate has already been described. It will further be understood that under tension applied between the valve plate and the nozzle plate by the spring 60, friction will hold the valve plate and lever 66 in any position in which they may be set against accidental movements. The flange 36 serves to direct the exhaust from the outer series of vanes circumferentially to the exhaust port 21 and prevents the setting up of eddy currents or crosscurrents that might impede exhaust. The exhaust from the outer series of vanes passes around the exterior of the segmental flange 35, while the exhaust from the inner series of vanes is directed to the exhaust port by the interior of said flange.

The rotor itself involves novel features of construction already described, but in respect to which the following comments may be helpful. The vanes or buckets 54 may be made either by casting, machining or otherwise, but they may be advantageously and cheaply produced in accurate form by means of the steel die casting radial direction is completely equalized and the shaft will be pressure-centered in respect to its journal, thereby very materially and, in fact, almost entirely eliminating friction and wear on the bearing.

The inner surface of the inner ring 53 should be made from five to eight thousandths of an inch less in diameter than the diameter of the exterior of the inner vanes, when the temperature of the metal elements is the same, and then said ring 53 should be heated and expanded for insertion around the ends of the inner vanes and then allowed tocontract onto the vanes, very firmly uniting the elements and making, in effect, almost an integral structure. Substantially the same statement is true in respect to the manner of application of the outer ring 52 around the outer ends of the outer vanes. In the process of construction, the faces of the rotor thus constructed and particularly the nozzle plate-engaging or co-operating face, should be accurately machined to a perfectlyflat surface or to a surface that will exactly correspond to the adjacent surface of the nozzle plate.

In the drawings I have illustrated and in the specification have described a turbine having a single rotor, but it will be understood in practice that the number of rotors may be increased, and that the various details of construction disclosed and claimed are capable of various modifications in their construction and arrangement of parts within the scope of the invention herein disclosed and claimed. The manner of making the .rotor reversible by the novel arrangement of vanes on the rotor, nozzle passages in the nozzle plate or element, and ports in the valve plate or element, is considered broadly new and is herein broadly claimed.

It will be noted that the rotor, the nozzle plate and the valve plate are described as having smooth fiat surfaces, but it will be understood that these surfaces may deviate from true planes as long as they are true surfaces of rotation, such, for example, as would be produced by a cutting tool moving outward on a straight or substantially straight line; and hence that the expression herein used in the specification and the claims, to wit: "true flat surfaces is used in a liberal sense to include such surfaces of rotation as will permit the rotor to move substantially or nearly in contact with the adjacent face of the nozzle plate, and the valve plate to move in contact with the adjacent face of said nozzle plate.

What I claim is:

1. A turbine comprising a casing having. admission and exhaust ports and between said ports, a flat-faced nozzle plate equipped with nozzle passages, a rotor having circumferentially spaced vanes, and a flat surface, arranged to run substantially in contact with the adjacent face of said nozzle plate, a port-equipped valve plate having a surface engageable with said fiat face of said nozzle plate, said rotor having a shaft extended through one side of said casing, a manually adjustable thrust-resisting shaft journaled in and extended through the other side of said casing, and clutch elements on the inner end of said last noted shaft and on said valve plate, connecting the two for common rotary adjustments.

2. The structure defined in claim 1 in further combination with a spring interposed between the clutch-acting elements of said thrust-resisting shaft and valve plate, pressure seating said valve plate against said nozzle plate.

3. The structure defined in claim 1 in which said rotor is provided with concentric circumferentially reversely arranged vanes, said nozzle plate is provided with circumferentially reversely oblique concentric series of nozzle passages, and said valve plate is provided with concentric series of ports, whereby the rotor may be pressure driven in reverse directions by adjustment of said valve plate.

4. The structure defined in claim 1 in which said casing is provided with removable head plates, one of which is removable with said rotor, and the other of which is removable with said thrust shaft.

5. A turbine comprising a casing having admission and exhaust ports and provided with detachable head plates at its opposite sides, a rotor within said casing having a shaft extended through and journaled in one of said head plates, a thrust shaft journaled in and extended through the other head plate, a nozzle plate secured Within said casing and having circumferentially spaced nozzle passages, a rotor having circumferentially spaced vanes, and a flat face arranged to run substantially in contact with the adjacent face of said nozzle plate, a portequipped valve plate having a surface engageable with the flat face of said nozzle plate, means connecting said valve plate and said thrust shaft for common rotary adjustments therewith, and means for imparting oscillatory adjustments to said thrust shaft and hence to said valve plate.

EMIL WESTMAN.

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