US 2324903 A
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July 20, 1943. R. BECKMAN ELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan. 28, 1939 3 Sheets-Sheet 1 r INVENTOR ATTORNEY July 20, 1943. R. BECKMAN ELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan. 28, 1939 5 Sheets-Sheet 2 54 W fiv2-\ xd I v 40 a 4 Q WM,
INVENTOR ATTORNEY July 20,1943. R. BECKIIVIAN 2,324,903
ELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan. 28, 1939 3 Sheets-Sheet 3 INVENTOR 6 J3 moi/524M ATTORNEY Patented July 20, 1943 ELASTIC FLUID LJMPRESSOR OR MOTOR Richard Beckman, New York, N. Y.,'assignor of one-half to Otto Gries, New York, N. Y.
Application January 28, 1939, Serial No. 253,252 4 Claims. (01. 230-152) This invention relates to rotary devices whereby elastic fluid, such as air, may be compressed and conversely the device may be driven as a motor by means of compressed elastic fluid.
One of the main objects of the invention is to provide a device of the character described which shall have. the losses of power in operation, greatly reduced.
Another of the main objects of the invention is to provide a. device of the character described wherein the wear of parts shall be reduced to a minimum.
A further object of the invention is to provide the mounting on the rotor of the radially movable vanes.
A further object of the invention is to provide in apparatus of the character described, a rotor having end heads serving as lateral guides for the vanes and preventing lateral friction of the rotor against the end heads of the stationary housing.
A further object of the invention is to provide improved means for insuring the forcing of the rotor vanes outwardly into contact with the surrounding cylindrical wall.
A further object of the invention is to provide a rotor mounted by stub shafts or trunnions at its ends instead of having a shaft extending entirely through the rotor as formerly.
A further object of the invention is to provide a freely rotatable cylinder encircling the rotor vanes, and. against which the vanes bear, whereby the friction and wear of the parts is greatly decreased.
A further object of the invention is to provide freely rotatable rings as bearings for mounting upon the stationary casing, the cylinder encircling the vanes as above referred to.
A further object of the invention is to provide fluid pressure means for forcing the vanes from the centre outwardly whereby undesirable bores or recesses in the rotor are made unnecessary.
A further object of the invention is to supply oil to the vane bearings by introducing it into the interior of the rotor hub.
A further object of the invention is to supply fluid pressure to the interior of the rotor hub, for forcing the vanes outwardly.
Other and ancillary objects of the invention will appear hereinafter.
In the accompanying drawings which illustrate the invention- Fig. 1 is a section on the line |l of Fig. 3;
Fig. 2 is a section on the line 22 of Fig. 1;
Fig. 3 is an end elevation of the device viewed from the left hand of Fig. 1;
Fig. 4 is a fragmentary section on the line 44 of Fig. 2 showing the manner of securing the end head of the rotor;
Fig. 5 is a fragmentary section on the line 55 of Fig. 2 showing the manner of mounting the roller bearing for a vane;
Fig. 6 is a fragmentary section on the line II of Fig. 3 but showing a modified form of floating bearing rings for the floating cylinder surrounding the rotor vanes; and
Fig. 7 is a diagram showing the fluid control when the device is operated as a motor.
Referring to the drawings, the apparatus is a compressor (or conversely a motor) of the rotary type wherein a rotor eccentrically mounted within a casing has vanes carried by the rotor which are forced outwardly against the surrounding walls.
As shown in the drawings, and referring first to Figs. 1 to 5 inclusive, the casing of the apparatus comprises a casing including the cylindrical portion 8 to which are secured the end heads 2 and 3. Within the casing is mounted a freely rotating cylinder 4, the ends of which fit into recesses in the end heads 2 and 3, and this cylinder d is supported at one end from the body of the casing by means'of a series 5 of overlying rings or bands, and the other end of the rotor is supported from the casing by means of a series of overlying rings or bands 5'. Both sets of bands extend entirely about the cylinder 5 and support nated construction, and in the instance illustrated bands 6 and i, each with an offset flange I 8, are provided on each side of the band 5, acting to prevent the latter from coming into wearing contact either with the end head 9 of the casing, or with the shoulder in upon the cylindrical part of the casing; and an additional band H is shown;-the entire assembly constituting a very easy-running bearing structure. The clearance l2 may be oil-filled to aid lubrication and to carry ofi the heat of operation.
Thus, wall friction is greatly reduced and higher speeds can be attained than with existing rotary vane compressors. Since the auxiliary cylinder 4 is to be regarded as a rotor, and is floating, preferably, th vanes V extending from the rotor proper, which is designated generally by the reference character R, will rotate the auxiliary rotor 4, by their pressure exerted against the saute, at approximately the same speed, and thus again diminish friction between the vanes, allowing great speed and displacements per time unit.
From the foregoing it will be understood that it is not necessary to provide for positive driving of the auxiliary rotor, but it is not intended to exclude the possibility of such actuation where found desirable and suitable.
In pursuance of a general object of the inventionto reduce friotionthe vaned rotor R is provided with certain novel features, as follows:
(1) It is provided with end heads l3 and I4, which rotate with it and serve as lateral guides for the vanes V preventing lateral friction of the rotor against the stationary end heads l5 and I6 of the casing, between which and the rotor head there may desirably be a slight clearance as indicated at H; these rotor heads are preferably formed as radial flanges upon hollow stub shafts or trunnions l8 and I9 which take the place of the usual shaft running through the vaned rotor; and in this novel structure a ball-bearing, as 20, is provided, for each trunnion, and fitted in suitable bosses 2i, 22 carried by the casing end heads l5 and I6; 2. known form of stufling box G is shown at one end of the rotor'and a packing ring 23 at the other end.
The hub 24 is provided with an axial bore 25 to which lubricant may be introduced through a, nozzle 26 screwed at 21 into the boss 2| and a conduit 28 is provided to place the cavity 29 of the boss in communication with the high-pressure side of the device so that a plenum of pressure may be maintained in the bore 25, tending to drive lubricant through ducts 30 which pierce the hub for that purpose communicating individually with the inner ends of the vane slots as shown at 3| in Fig. 2. Thus lubricant can be fed to the vanes V under pressure and at the same time, in pursuance of another object of the invention, the vanes are biased to their outer working position.
(2) Each vane has a head 33 which fits snugly in its slot 33 and the shanks 34 are reduced in diameter as at 35 to diminish friction; for the same purpose the wall of each vane slot is enlarged as at 36 to afford clearance, and at this region each of the spokes 31 of the rotor has an enlargement 38 in which is formed a recess 3'9 that serves as a bearing for an anti-friction member 40 shown as a hollow roller in the instances illustrated but which may be of any suitable form.
(3) The vane slots 33 are not disposed in true radial alignment with the axis of rotation, but each is formed at an angle to the radius which intersects the centre line of the slot at the mouth thereof, so that each vane is inclined, as illustrated clearly in Fig. 2, preferably with its outer end 34 ahead of the head 32. By this arrangement the invention prevents edging of the vanes at the in-stroke, since a certain thrust is exerted upon each vane, backwards of the theoretical centre line of the vane, as well as backwards of the direction of rotation of the rotor. It will be observed also that the rollers 40 aid to take up the sidewise component of the thrust. The rotor may be secured to its end heads, as by screws 4|, tapped into flanges 42 (see Fig. 4).
Suitable provision may be madefor cooling the structure as by conventional ribs 43, also by water jackets (not shown) wherever desired.
In Fig. 3 the inlet is shown at 44 and the outlet at 45, thes positions being optional, of course, and variable to suit the exigencies of particular installations, as are other structural features of the casing.
From the foregoing disclosure, it will be understood readily that substantial advantages are obtained in addition to those already noted, and among which may be mentioned the following:
(a) Volumetric efiiciency is very much higher than with any other compressor, due to the complete displacement and the absence of waste space.
(1)) pressures at all speeds are uniform.
(c) vibrationless and noiseless operation is secured.
(d) not only is friction greatly reduced, but abrasive action is virtually eliminated, owing to the exclusion of dust, which in conventional vanetype compressors, piles up ahead of the vanes at their contacting ends.
(e) the rotor end-covers form a lateral seal being recessed into the housing covers.
(I) wear and tear of the vanes is compensated automatically and a perfect seal maintained at all times.
When the device is'operated as a motor the source of fluid pressure would be connected to the outlet 45 but the vanes V must be in extended position when the power is applied. Accordingly a control device should be employed whereby the pressure would be first applied to the inner ends of the vanes, forcing them into extended position in the manner as described above and the pressure then applied to the opening 45 (outlet when operating as compressor). Such a control is schematically shown in Fig. 7. In that figure the pipe 50 connects the cylinder 5| with the chamber at the inner ends of the vanes V, while a pipe 52 connects the cylinder with the opening 45. Also a pipe 53 from a source of motive fluid pressure, connects with the cylinder 5|. When the piston 54 which slides in the cylinder, and may be moved by the hand piston rod 55, is in the position as shown in the draw-' ings, the fluid pressure of pipe 53 is cut off from both pipes '50 and 52. As the piston is slid to the right (Fig. 7) however, the end of the pipe 50 is first uncovered whereupon the vanes are forced into extended (outward radially) position and then as the piston is moved further to the right the pipe 52 is uncovered and motive pressure is supplied to the motor. Obviously the power may be shut 01f by returning the piston to its original position.
While the invention has been illustrated in what is considered its best application, it may have other embodiments without departing from its spirit and is not, therefore, limited to' the structures shown in the drawings.
What I claim is:
1. A fluid-pressure device comprising in combination a main cylinder casing, an eccentric rotor piston with reciprocating vanes rotatably mounted in said casing, fluid-pressure chambers between said vanes and an auxiliary cylindrical rotor concentrically mounted in said casing and surrounding said vanes and the fluid-pressure chambers therebetween and a series of bearing rings at each end of said rotor through which said cylindrical rotor is mounted upon said casing, said cylindrical rotor being freely rotatable, the bearing rings of each series being arranged one outside the other, the outer ring of the said series bearing against the said casing and the inner ring of said series bearing against said cylindrical rotor, said bearing rings each having a cross section greater axially than radially of said rotor and said rings bearing upon'one another, said casing or said rotor for the greater portion of their extent axially of said rotor,'said rings being slidable upon, and freely rotatable with relation to each other and to said cylindrical rotor and to said casing and to said vanes, and intakeand discharge means for said chambers.
2. A fluid-pressure device having the features claimed in claim '1 in which at least one of the said bearing rings has a radial flange interposed between another of the rings and a wall of said casing.
3. A fluidpressure device comprising in combination a stationary main cylinder casing, an eccentric rotor piston with reciprocating vanes, rotatably mounted in said casing, said eccentric rotor piston having a hub and radial slots for said vanes, each of said vanes having an inner head having-a snug slide fit in its vane slot and a shank of less thickness, the opening of said slot being of a larger cross sectional area than the vane for a substantial distance inward from the mouth of the slot, said slots having a recessed wall portion, an anti-friction member for each vane mounted rotatably in said recessed portion 4. A fluid-pressure device comprising in comprising in combination a stationary main cylinder casing, an eccentric rotor piston with reciprocating vanes, rotatably mounted in said casing, said eccentric rotor piston having a hub and radial slots for said vanes, each of said vanes having an inner head having a snug slide fit in its vane slot and a shank of less thickness, the opening of said slot being of a larger cross sectional area than the vane tor a substantial distance inward from the mouth of the slot, said slots having a recessed wall portion, an anti-friction roller for each vane mounted rotatably in said recessed portion of the slot wall, said roller being disposed in the slot wall which drives the vane, means for forcing the vanes outwardly by elastic fluid-pressure and fluid inlet and outlet ports RICHARD BECKMAN.