US2657676A - Rotary power machine - Google Patents

Description

G. E. MALLINCKRODT Nov. 3, 1953 ROTARY POWER MACHINE 3 Sheets-Sheet Fi led Sept. 8, 1951 G. E. MALLINCKRODT Nov. 3, 1953 ROTARY POWER MACHINE Filed Sept. 8, 1951 3 Sheets-Sheet 2 G. E. MALLINCKRODT ROTARY POWER MACHINE Nov. 3, 1953 5 SheetsSheet 5 Filed Sept. 8, 1951 Patented Nov. 3, 1953 UNITED STATES PATENT OFFICE ROTARY POWER MACHINE George E. Mallinckrodt, St. Louis, Mo. Application September 8, 1951, Serial No. 245,759

Claims.

This invention relates to rotary power machines, and constitutes an improvement upon constructions such as shown in my copencling United States patent applications, Serial No. 183,846, filed September 8, 1950; and Serial No. 194,599, dated November 8, 1950 (eventuated as Patent No. 2,638,880) both for Rotary Expansion Engine.

Among the several objects of the invention maybe noted the'provision of a rotary expansion engine incorporating a simple starting mechanismoperable without any especially introduced pressure medium such-as air; the provision of apparatus of the class described which permits the engine to be externally cranked by hand or otherwise for starting; and the provision of apparatus of this class which provides not only for starting the engine as stated but serves to maintain the compression ratio and efficiency of the engine at low operating speeds.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts'which will be exemplified in the structures hereinafter described, and the scope of which will be indicated in the following claims.

In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated,

Fig. 1 is an axial section of a rotary engine embodying the invention;

line 2-2 of Fig. 2 is a cross section taken on Fig. 1;

Fig. 3 is a cross section taken on line 33 of Fig. 1;

Fig. 4 is a cross section taken on line i-i of Fig. 1; and,

Fig. 5 is a cross section taken on line 5-5 of Fig. 1.

Similar reference characters indicate corresponding parts throughout the, several views of the drawings.

Referring now more particularly to Fig; 1, there is shown at. I: a cylinder having end. bells 3 and 5 forming a toroidal or annular working chamber 1. The1end'bells'3 and 5 are enclosedby heads 9 and H, respectively, in which are bearings l3 and I5.

Bearing l3 supportsa rotor A andbearing 5.5 supports a rotor B. Rotor A consists of a sleeve l'l- (supported by bearing l3 and anintegr'al cupshapedmember l9.which carries pistons W. and X spaced at 180 in. the working chamber 3. Rotor B consists of a sleeve 2| (supported by bearing l5) and an integral.cup-shapedmember 23 which carriespistons Y and Z spaced at 180 in the working chamber 1. A collar 25 joins the pistons W and X with the cup l9 and a collar 21 joins the pistons Y and Z with the cup 23. A sealing ring 29 is employed between the collars 25 and 27; another sealing ring BI is employed between the collar 25 and the end bell 3; and another sealing ring 33 is employed between the collar 21 and the end bell 5.

At 35 is shown a power shaft carried upon bearings 31 within the cup 19 and upon bearings 39 within the cup 23. Inner sleeve members 4| and 43, attached to the cups l9 and 23, respectively, carry the outer races of the bearings 3'! and 39. Attached respectively to the members it and 33, and hence to rotor A and B, are bevel gears 45 and 51. Bevel pinions 49 are carried on a cross arm 5| attached to the shaft 35. Thus the bevel gears 45, Al, pinions 49 and stud 5| form differential driving gearing between both rotors A and B on the one hand and the shaft 35.

As shown in Fig. 3, the annular working space I has an intake port 53 and an exhaust port 55. An ignition device in the form of a sparkplug is shown at 51. This is located in a recess in a wall of the working chamber 1 so that pistons W, X, Y, and Z may pass it. This plug requires no timer for ignition, being of the continuously operating type. The ignition device may also be constituted by a hot-bulb or like ignition arrangement.

The sleeves I1 and 21 extend out from the heads 9 and II, respectively. The shaft 35 carries extensions 59 and 6! which also extend outward from said respective heads 9 and H, passing through the sleeves I! and 2i. A sealing gland 53 is employed between the sleeve H and extension 59, and another sealing gland is employed between the sleeve 2! and extensional. A flywheel E1 for rotor A is carried on the sleeve I1 and a flywheel 69 for rotor B is carried on the sleeve 2i. These flywheels are identical and a description of one will serve to describe both (in this connection see Fig. l). Each carries two recesses ll inwhich are pinned centrifugally 0P- erated inertia weights E3. The centers of gravity of weights 13 are so located in respect to their pivot pins 15 that the weights tend to move outward when the respective flywheel rotates.

The maximum outward positions are determined by the stop engagements indicated at H. Gradual stop engagement occurs upon deceleration of the respective flywheel. Upon angular acceleration or a flywheel the weights 13 tend to lie back in the recesses H. The moment of inertia of =3 each flywheel E? or 58 (including its weights T3) is greater when the weights '53 are outward than when inward.

Backward rotation of rotors A and B is limited by reverse locking ratchets or clutches is and Si respectively. Both clutches is and iii are the same and the description of one will serve as a description for the other (Fig. 5). Each is constituted by a cylindric sleeve 83 fixed in the respective end bell 3' or ii as the case may be. These sleeves are internally notched as shown at 35 (Fig. 5), providing recessed portions and backstop portions which are adjacently located. The notch s in each sleeve are 180 apart. The two sleeves are so related in their angular positions around the center line of shaft 35 tha u their four notches are in the same plane, where the spring anchoring means 88 and i are at ninety degree intervals when W, X, Y, Z are as shown in Fig. 3 and the springs 87 are of the same length. Each clutch includes a spiral spring band 8'? anchored at one end to the respective sleeve 59 or 23 as the case may be. The anchoring studs for the clutch is are shown at 8 (Fig. 1), while those for clutch 81 are shown at 95 (Fig. 5). For anticlockwise rotation of the flywheels as shown in Fig. l (and from the right in Fig. 1) the spiral springs 8? are wrapped clockwise (Fig. 5).

The description thus far given is of apparatus corresponding basically to what is shown in Patent No. 2,638,880, and is given herein to disclose the background of the present invention (described below). Before giving such descrip tion the operation of the machine thus far de scribed will be given so that the point of departure of the invention from what has before will be apparent. This operation is briefly as follows, assuming that operating as an engine it is under way:

When a previously compressed charge in quadrant I (Fig. 3), is exposed to ignition by the plug, a driving action occurs on piston Z with reaction on piston W. Piston W cannot move backward (clockwise) because of the re verse-locking action of clutch is. Piston Y is compressing a charge against piston W in quadrant IV. A new charge is being drawn in at port 53 in quadrant III by the suction action of driven piston Y. As piston Z moves through quadrant II, exhaust occurs through port 555. This reduces the reaction on piston W so that it may be moved as piston Y compresses against it a previously drawn-in gas charge. As the approach occurs, energy is transferred from rotor B to rotor A through the compression on the charge between pistons Y and W. This decelerates rotor B and its weights is move outward to increase its moment of inertia. As rotor A accelerates, its weights '53 fold back thereby decreasing its moment of inertia. Thus there is assurance that before all of the energy is transferred between rotors piston Y will follow piston W with the compressed charge therebetween until piston W crosses the position of the plug 5 and Y at least moves up to the locked position occupied by W in Fig. 3. Preferably Y will slightly overrun this position.

The pairs of pistons W, X and Y, 2 then become interchanged in positions, the pair W, X then doing the work and Y, Z, providing the reactions for the expansion and suction events. The weights associated with the pistons W and X (rotor A) upon initial acceleration first fold backward then gradually move outward under centrifugal force as the velocity of rotor A increases. Upon the subsequent deceleration of pistons W and X the weights it of rotor A more out and energy is transferred from rotor A to rotor B under such conditions that piston X can take the place of piston Y at the top of Fig. 3. The weights of accelerating rotor B at this time fold back. This is a sufiicient description of oper-- ation to show how it continues. There are two each of power, suction, compression and exhaust events per revolution of shaft The intermittent rotations of rotors A and are transmitted to the shaft 35 through the differential gearing 45, M, 9, 5i. As described in said Patent No. 2,638,880,, it is the property of such gearing that the velocity of shaft 35 will be substantially constant when connected to a device having a substantial moment of iner" such as an electrical generator, flywheel or like.

As indicated by said applications, air-starting devices were practically necessary. This was cause upon external cranking not enough resist-- ance could be obtained from one rotor A or B to cause the other to overtake it sumciently to bring about the succession of suction and compression events which form the conditions precedent to an effective expansion event.

The present invention overcomes the above requirement for air-starting equipment. This is accomplished by connecting the rotors A and B by a resilient torsional connection, which in the present embodiment comprises a coil spring 92%. One end of the spring 83 is anchored at 95 to rotor A and the other end at 9! to rotor B. The spring thus connecting the rotors A and B forms with them a substantially freely oscillating torsional system comprising the spring-coupled rotors. This system when substantially freely oscillating will have a natural torsional period. This is arranged to be equal to the period required for one revolution of the shaft 35 at cranking speed. One half of this torsional period, which is a half. period of oscillation, and which is also the time required for one rotor to advance and displace the other, is equal to the period, required at cranking speed, for the ends of springs ill to traverse successive notches 85. For example, at a cranking speed of approximately R. P. IVL, if the average moment of inertia of each rotor is 0.66 lbs. ft. the coil spring will have a wire 60 inches long between anchors. the wire being 6 mm. in diameter, assuming a modulus of rigidity for the spring material of 8x10 dynes per sq. cm. The number of coils in the spring 93 are dependent upon the diameter required for it to clear the ends of the stud 5!. Starting can be then accomplished by cranking shaft 35 at or about 150 R. P. M. This will cause forward movement to both rotors A and B, assuming they have equal frictional resistances against rotation. Then, whichever clutch spring 8! first moves its trailing end over a notch 35, sets up some increased resistance to movement of its rotor (say rotor A). The other rotor (say rotor 13) will then execute a slight overtaking movement winding the spring 93. The spring force added to that of the compressed charge between the rotor pistons, will dislodge the spring 8'! from the said notch 85 and oscillation will start in the spring connected rotor system. The frequency of this oscillation is such that by the time the end of spring 81 of the rotor B drops into the next respective notch 85, the resulting cranking torque applied to rotor A will be aided by the oscillating force of rotor A. Hence the spring 8! of rotor B is moved from its notch 85 with an added increment offorce. Rotor B in execution of its part oftheoscillation will then add anadditional force to the cranking force for advancing-rotor A when next its drag increases by reason of movement of its spring 87 over its next notch 85. Thusthe compression'force during each successive compression event builds up until conditions are proper for operation which will then automatically set in.

In the case of some designs of the engine it may be that the small amounts of friction or hanging afforded by the ends of springs 81 crossing notches 85 is insufficient to gain a threshold value of force which will instigate the buildup of the desired oscillations. In this event stronger drag-operating devices 99 and IBI are used. Since these are identical in structure, drag device till only will be described (see Figs. 1 and 2). Each of these devices consists of a catch arm H33, pivoted at I to a lug It! on an adjacenthead 9 or II as the case may be. Dog I09 on arm its engages a cam III on the respectively adjacent flywheel 61 or 69 as the case may be. The arm I93 is biased toward the cam by a spring H3 anchored to the arm at H5 and extending to another lug II I on head 9 or I i. Each cam III has oppositely located notches H9 and intermediate lobes IZI. Engagement of lug I09 in a notch H9 results in applying a substantial holding action to the rotor connected with the flywheel in question. This holding action is greater than that afforded by the movements of the'ends of springs 81 over notches 85. However, it is not positive, so that when suflicient force is supplied to the respective rotor its respective cam III can be moved. As the cam II!v advances, the next succeeding lobe I2I will raise the lug I69 and finger I23. If the cam moves fast enough this finger will rise by inertia to a higher position. At I25 is shown a catch mechanism which has a sleeve I21 forming another extension from one of the heads 9 or I I. In this sleeve is catch I29 biased outward by a spring I3! and adapted to be retracted by a pull ring I33. The action between the catch I29 and finger H3 is such that when the lobe l2I rides slowly under the lug I99, catch I29 will not be passed by the finger I23. When I2I rides quickly under the lug IE9 the inertia sends the lever I93 out far enough so that the finger I28 is caught behind the catch I29.

The holding action of the drag-operating devices 89 and I9! is similar to that above described in connection with the clutches I9 and 9! insofar as starting action in concerned. At cranking speeds, the movements of the springconnected rotors will be successively resisted by engagement of lugs I99 in notches IIQ asoscillations build up. At these speeds the lobes I2I do not move fast enough to kick the lever I03 permanently out past catch I29. As soon astheengine fires and increases speed above cranking speed, lever IE3 will be kicked" out sufilciently that finger I23 will be caught outside by catch I29 so that drag devices become inoperative during power operation of the engine. After shutting off the engine it may be prepared for a second start by pulling out the rings, thus releasing the fingers I23 from the catches I29 so that the drag devices 99 and It! become operative.

Not only is the invention useful for starting purposes, but upon reduction in operating speed of the engine the stated oscillations tend to set in, which at the lower speeds adds to the compressive force available during. interchange of momentum between the rotors. This tends to prevent the compression ratio from being redined at very'low speeds, thereby increasing lowspeed efficiencies. The effect sets in automatically'as the speed approaches resonance speed.

It will be understood that although the invention is described in connection with a rotary engine having inertia weights such as and shown in said Patent No. 2,638,880, it is also effective in connection with apparatus without such weights as in said application Serial No. 183,846. It is to be understood that the reverselocking means of clutches I9 and 9| is constituted by the ends of springs 81 bearing upon the radial portions of the notches 85, and that the intermittent drag effects are distinct, being du to the extra force engendered against rotation by dragging springs 8'! over the notches, thus, the intermittent drag effects of the notches are distinct from the reverse locking effects, the former being due to pulling the springs forward out of the notches and the lattter being due to driving the springs back into the notches.

From the above it will be clear that under starting conditions the machine operates in the manner of a compressor, and it is to be understood that the dependent claims cover both rotary expansion engines and compressors employing the elements otherwise set forth in the respective claims.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A rotary machine operative in connection with an expansive and compressive gaseous medium, comprising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, the pistons being operative in connection with said medium, a reverse-locking means between each rotor and the frame, intermittently operative drag means between each rotor and the frame, a differential gear train between each rotor and the shaft, and a coil spring connecting adjacent ends of the rotors and surrounding the differential gear train.

2. Apparatus made according to claim 1, whereineach of said drag means is constituted by a spring -operated detent means between the frame and the rotary part associated with the shaft, and wherein is included means adapted automatically to disconnect the detent means operative only above a predetermined shaft speed.

3. Apparatus made according to claim 2, ineluding-manual means adapted to reconnect said detent means.

i. A rotary machine operative in connection with an expansive and compressive medium, comprising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, a reverse-locking means between each rotor and the frame, said means being positively operative against rearward rotor movement, nonpositively operative and intermittent drag means between each rotor and the frame non-positively operable against forward movement, and sprin means connecting the rotors.

5. A rotary machine operative in connection with an expansive and compressive medium, com prising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, drive means operative between each rotor and the shaf, spring means connecting the rotors, the rotors of the system constituted by the rotors and the spring connection being substantially freely oscillatory relative to one another, non-positive resistance means between the rotors and the frame which means are intermittently operative at a frequency proportional to the shaft speed, the oscillatory system having a half period of oscillation equal to the period between successive operations at a predetermined shaft speed of the resistance means.

6. A rotary machine operative in connection with gaseous medium, comprising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, the pistons being cooperative through said medium, drive means operative between each rotor and the shaft, spring means connecting the rotors, the rotors of the system constituted by the rotors and the spring connection being oscillatory relative to one another when the shaft is turned at a predetermined cranking speed, non-positive resistance means between the respective rotors and the frame which are each intermittently opera tive upon rotation at a frequency which is in proportion to the cranking speed of said shaft, said oscillatory system having a half period of oscillation substantially equal to the period between successive operations of the resistanc means between both rotors and the frame when the shaft turns at said cranking speed.

'7. A rotary machine operative in connection with an expansive and compressive medium, con prising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, a reverse-locking means between each rotor and the frame consisting of a spiral spring anchored to the respective rotor and spiraling backward relative to rotor movement and having a free trailing end, each reverse-locking means also including a backstop on the frame with which said trailing end may reverse lock, non-positive intermittently operative drag means between each rotor and the frame, each dra means being constituted by one of said trailing spring ends and a recessed portion forming one of said backstops, and spring means connecting the rotors.

8. A rotary machine comprising a frame, a pair of rotors, spring means connecting th rotors, reverse locking means between the rotors and the frame, th system constituted by the rotors and the spring means being substantially freely oscillatory as between its rotors according to a certain period as the system turns in one direction, non-positive resistance means between each rotor and the frame each of which non-positive resistance means i intermittently operative according to a period dependent upon the shaft speed when th latter is cranked, the half period of said oscillatory system being equal to the period between intermittent operations of the drag means when the shaft is cranked at a predetermined speed, whereby incipient oscillations of said system may be introduced and their amplitudes increased to effect operation upon cranking of the shaft at said cranking speed.

9. A rotar machine operative in connection with an expansive and compressive medium, comprising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber, positive reverse-locking means between each rotor and the frame, spring means connecting the rotors, differential means connecting the rotors and the shaft whereby each rotor may drive the shaft when the other is reverse locked and whereby when the shaft is cranked the rotors of the system constituted by the rotors and the spring means between them may oscillate, non-positive resistance means between hte rotors and the frame which upon rotation of the shaft are intermittently operative at a frequency proportional to the shaft speed, said. oscillatory system having half period of oscillation equal to the period between successive operations of said resistance at the cranking speed of the shaft.

10, A rotary machine operative in connection with an expansive and compressive medium, comprising a frame, a shaft, an annular chamber connected with the frame, at least one pair of rotors, each rotor having at least one piston in the chamber and at least one weight movable outward upon angular deceleration, reverse-locking means between each rotor and the frame, spring means connecting the rotors, differential gearing connecting the rotors and the shaft whereby each rotor may drive the shaft when the other is reverse locked and whereby when the shaft is cranked the rotors of the system constituted by the rotors and the spring means between them may oscillate, non-positive resistance means between the rotors and the frame which upon rotation of the shaft are intermittently operative at a frequency proportional to the shaft speed, said oscillatory system having a half period of oscillation equal to the period between successive operations of said resistance means.

GEORGE E. MALLINCKRODT.

References Cited in the file of this patent FOREIGN PATENTS Number Country Date 4 9,722 France Nov. 3, 1910 159,372 Great Britain Mar. 3, 1921

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