US2149591A - Crankless diesel engine - Google Patents

Description

-March 7, 1939. F. J. FETTE 2,149,591

CRANKLESS DlESEL ENGINE Filed Oct. 7, 1935 3 Sheets-Sheet 1 INVENTOR. 7 2 7 fiM/VK J FfTTf,

( 44. 63 BY W my My. m i v ATTORNEYS.

March 7, 1939. F. J. FETTE 2,149,591

CRANKLESS DIESEL ENGINE Filed 001.. 7, 1935 3 Sheets-Sheet 2 INVENT OR. fie/41w: J FETIE,

. ATTORNEYX March 7, 1939. F FETTE 2,149,591

CRANKLESS DIESEL ENGINE Filed Oct. '7, 1935 3 Sheets-Sheet 3 /Z Q23) E7 V 2 j 2 2 :4 s 32 4 47 IN VENTOR.

ATTORNEY.

Patented Mar. 7, 1939 UNITED STATES 3 Claims.

My invention relates to internal. combustion engines and more especially to engines of that character in which the motive force is trans mitted by means of a piston element bearing against an endless cam track in such a way that the reciprocating motion of the piston is transformed into a rotary motion.

It has been proposed to utilize this principle in internal combustion engines wherein the endless cam track is stationary and the cylinder rotates. one object of my invention is to simplify and increase the eniciency of engines operating upon the principle above explained by providing the cylinder as the stationary structure and providing the endless cam track as a part of the rotary structure.

My invention also relates to engines of the Diesel type; that is, engines in which a body of air is compressed to such a high degree that its temperatureis raised sufficiently to ignite the fuel, usually a heavy fuel oil, which is injected into the highly compressed air at or slightly after the instant of greatest compression.

My invention also relates to engines of the two-stroke cycle type and a further object is to provide the highly compressed air by means of simple construction permitted by utilizing the same cam track for operating a plunger in an air-compression cylinder forming part of the stationary structure along with the power cylinder.

Afurther object of my invention is to provide for governing the amount of each fuel injection. 7

Other objects will appear in the course of the following description illustrated by the accompanying drawings in which:

Fig. 1 is a front elevation of an engine embodying my invention;

Fig. 2 is a side elevation of the same;

Fig. 3 is a vertical cross-section on the line 3-3 of Fig. 2 on an enlarged scale showing the detailed constrution of the governor;

Fig. 4 is a horizontal section of the governor on the line 4-4 of Fig. 3;

Fig. 5 is a vertical front-to-rear section on the line 5-5 of Fig. 1; I I

Fig. 6 is a vertical cross-section on the line 6-6 of Fi 5;

Fig. 7 is a partial horizontal section on the line 1-1 of Fig. 5.

In the example of my invention disclosed herein a base i has a pair of transversely spaced pedestals 2 near its front end which pedestals are joined by a transverse portion 3 intermediate of their height. This base has near its rear end midway of its width a pedestal 4 in the top of which is a bearing 5 for the horizontal main shaft 6.

The stationary cylinder structure comprises the diametrically opposed power cylinders l which are continuous with each other at the center of the structure, and the air-compres-- sion cylinders 8 which are aligned on the center of the structure at right angles to the power cylinders 1 with inner closed ends formed by portions of the walls of the power cylinders.

This cylinder structure is supported on the pair of front pedestals 2; having brackets 9 fixed to the tops of the respective pedestals by screws Ill, as best seen in Figs. 1 and 2, and also having the bottom front part of the structure secured to the transverse junction portion 3 by screws II. The cylinder structure thus extends backward from the pedestals 2; and it is so positioned that the center lines of the two pairs of cylinders l and 8 cross on the projected center line of the main shaft 5 which has its front end portion turning in a bearing [2 projecting rearwardly from the stationary cylinder structure.

The endless cam structure comprises a rim l3 mounted on the front of the rim portion of a disk M which has a hub l5 secured to the shaft 6 by a key I6 between the two bearings 5 and I2. The rim l3 has the inwardly projected annular rear flange l1; and an annular flange member I8 is fixed to the front of the rim l3 and projects inwardly leaving a space between it and the rear flange H. The inner edges of these flange portions I1 and I8 are circular and concentric with the shaft 6; and the cylinders l and 8 are so proportioned that they merely have a suitable clearance between them and these inner flange edges. These flange members I! and l 8 have formed in their inner mutually facing sides the endless cam grooves l9 and 20 respectively. The power pistons 2| in the power cylinders l havestems 22 and the air-compression plungers 23 in the compression cylinders 8 have stems 24; these stems 22 and 24 projecting through the outer ends of the respective cylinders into the space between the flange members I! and IS with transverse pins 25 and 26 respectively journaled in their outer end portions with 50 projections from their opposite sides on which are fixed rollers 2'5 and 28 respectively which bear in the cam grooves 19 and 28. The power cylinders l have guides 22a for the piston stems 22, and the air cylinders 8 have guides 24a for the plunger stems 24, extending out betwen the flange members i! and I8.

The cam grooves l9 and 20 of the flange memhers I! and 58 are of an elliptical shape, modified in that opposite portions 29 on the minor axis curve slightly inwardly and then outwardly symmetrically to this minor axis; the remainder of the extent being made up of circular arcs 30 continuous with these inwardly curved portions 29 and symmetrical to the major axis. It will be understood that the major and minor axes cross on the projected center line of the shaft 6 where the center lines of the cylinders cross as before explained; and that the cam grooves l9 and 23 have their above-described formations coinciding so that both groovesreceive the respective rollers 21 and 28 accurately at all points throughout their extents.

The stationary cylinder structure includes a water jacket 3! which surrounds the four cylinports for admission of air and fuel and for exhaust of the combustion gases.

Each air-compression cylinder 8 has one of the above air ports 32 and one of the power cylinders 1 has one of the above air ports 33. The compression cylinder ports 32 are at the inner ends of the respective cylinders 8 and the power cylinder port 33 is so located that it will be uncovered by the power piston 2i only when this piston is at the outer end of its stroke. The ports 32 and the port 33 are connected by a U-shaped conduit 34 on the front of the front water jacket wall. An air chamber 35 has a connection 36 to this conduit; and a check valve 31 is arranged to admit air to the chamber 35 but prevent escape of air therefrom.

The exhaust port 33 formed through one of the extensions above mentioned leads from the other power cylinder at such a location that it is uncovered by the other power piston 2! only when this piston is at the outer end of its stroke. An exhaust pipe 39 leads from this port 38 at the front and it will be understood that it may be connected to any suitable means for disposing of the exhaust gases. in through the remaining-one of the above-mentioned extensions at the center of the cylinder structure; at which point it willbe unobstructed by the power pistons 2| when these pistons are at the inner ends of their strokes with a clearance between them which forms the space wherein occurs the combustion of the fuel admitted from the pipe 40. r we The rim I3 is secured to the disk.l4 and the front flange structure I8 is secured to the rim l3 by transverse bolts 4!. It will be seen that this rotor structure forms the fly wheelof the engine. When the rollers 21 of the power pistons 2! are at the innermost points of the inwardly curvedportions 23 of the cam grooves l9 and 23 the power pistons 2i will be at the inner ends of their strokes. The compression pistons will be at the outer ends of their strokes at this time with their rollers 28 on the major axis of he cam groove formation. It may be considered how that the power pistons 2i have compressed a body of air between them and that fuel is injected through the pipe 48 to be ignited by the heat of the compressed air. The

The fuel inlet pipe 45) leads' momentum of the fly wheel structure will have carried the innermost points of the portions 29 slightly past the rollers 27 so that these rollers will be bearing on outwardly receding portions of the outer walls of the cam grooves and will thus impart further rotative force to the fly wheel structure throughout a quarter revolution until the power piston rollers 2i reach the major axis. Until this time the air inlet port 33 and exhaust port 38 will be covered and closed by the power pistons 2| which have the usual sealing rings 42; and the compression plungers 23 will be moved inwardly as the cam rotates the points of its major axis away from these rollers and brings to them the inwardly curved parts 29. Thus during an expansion stroke of the power pistons the compression pistons will be given a compression stroke which will compress a charge of air in the spaces at the inner ends of the compression cylinders 8 and in the ports 32, conduit 34, connection 36 and air chamber 35. This air chamber is provided to sufiiciently enlarge this space to avoid excessive compression of this charge of air; it being understood that this air is compressed only sufficiently to enable it to readily enter the power cylinders as the air inlet port 33 is uncovered. This will occur just as the compression is completed; and as the exhaust port 38 also is uncovered at this instant the gases of combustion will escape therethrough by expansion and also under the action of the incoming charge of fresh air through ports 33.

The momentum of the fly wheel structure now will continue the rotation so that the rollers 28 of the compression pistons 23 will be acted upon by the inner walls of the cam grooves where they curve outwardly from the minor axis in the cam portions 29 the cams continuing to withdraw the plungers 23 for the next quarter revolution until the major axis portions of the cams have reached the rollers 28. Very soon after this action commences the power piston 1 will have covered the power cylinder air inlet port 33 and the suction now created will open the check valve 31 so that atmospheric air is drawn into the air-compression cylinders during this quarter revolution. At the beginning of the next quarter the air-compression pistons 23 will cover the ports 32 and the check valve 31 will close under the increased pressure and another cycle will begin with compression of air; the power pistons having their expansion stroke after admission and ignition of fuel as previously described.

The fuel inlet pipe 40 leads from the fuel pump '43 which is located on the front of the rear pedestal 4; the pipe 40 curvingto one side of the fly wheel and front pedestal structures to extend up along the front of the engine to its cylinder entrance at the center of the front. As here shown the fuel pump 43 comprises a vertical cylinder in which fits a plunger 44 below which a pipe 45 leads down to a horizontal valve chamber 46 from the front end of which the pipe 43 leads to the cylinders. A pipe 4'! leads into the rear end of this chamber 43; being understood to lead from a suitable fuel supply device not shown. The check valves 48 and 49 open forwardly in the chamber 43; the valve 48 between pipe 41 and pipe 45 and the valve 49 between pipe 45 and pipe 40; so that valve 48 opens and valve 49 closes as plunger 44 rises to draw fuel into the cylinder 43 and pipe 45. Then, as plunger 44 descends, rear valve 48 closes and front valve 49' opens and admits the fuel to the power cylinders. The plunger 44 has an upwardly extended stem 50, on the upper end of whichris the fork A helical spring 52surroun-ds the stem 50 between the cylinder 53. and the fork 5i and forces the plunger 44 upwardly. Guides 53 extending forwardly from the rear pedestal 45 straddle the fork 5| and this fork has journaled in it a roller 54.

The hub I5 of the fly wheel structure previously described has a hollow cylindrical rearward extension 55 concentric with the shaft 5; and the roller 54 bears upward against the exterior of this extension by the pressure of the spring 52. Inside this hollow extension 55 a ring 55 is mounted to turn on the shaft 9 and has opposite extended segments 51 as best seen in Figs. 3 and 4 which have respective rearwardly projected cam ribs 58 which are eccentric to the shaft 5. These ribs 58 support cam blocks 59 which are mounted to slide radially in the shell of the hollow extension 55 at opposite sides thereof and have slots in which the cam ribs 58 fit snugly but slidably. These ribs 58 being eccentric, aturning of their supporting ring 56 on the shaft 6 relative to the hub extension 58 which is fixed on the shaft results in sliding the cam blocks 59 inwardly or outwardly. Weight members 59 are located at opposite sides of the hub i 5 each with one end pivoted to the hub at 6! from which the weight member curves around the hub. Therother end of each weight member has a fork 62 through which extends a respective rod 63 with a roller 64 bear-. ing on the outer surface of the fork 52. The rods 63 extend through openings in the shell of the hollow extension 55 and have their inner ends pivoted to the ring 55 at 54. Each rod has a helical spring 65 surrounding it between a shoulder 66 on the'rod and a bushing nut 9! threaded in the opening of the shell around the rod 63. By screwing this bushing nut 61 inward or outward the spring 65 may be more or less compressed to more or less resist the outward swinging of the respective weight 59 under centrifugal action. The parts are so proportioned that when the weights 69 are at their innermost positions the springs 65 acting through the rods 53 are permitted to rotate the ring 55 so that the cam ribs 58 project the cam blocks 59 farthest outward. Increase of speed and consequent outward swinging of the weights 59 pulling outward on the rods 53 results in rotation of the ring 55 so that the cam ribs 58 draw the cam blocks 59 inward.

The roller 54 on the fuel pump plunger stem being in the path of the cam blocks 59 is engaged by these cam blocks which force the plunger 54 downward to inject fuel into the cylinders. The degree of downward stroke of the plunger 55 will be greater or less accordingly as the cam blocks 59 are more or less extended. Thus increased speed of the engine decreases the amount of fuel supply so that the speed of the engine may be governed within close limits which will be determined by adjustment of the pressure of the springs 95 by adjusting the bushing nuts El. Also the supply of fuel to the pump 53 may be varied by adjusting the valve 59 in the supply pipe 57; this valve 53 serving as a throttle to vary the speed of the engine and the governor serving to keep the speed uniform in any degree permitted by the adjustment of the throttle 58.

It will be understood that the cam blocks 59 are located on a diameter through the center of the shaft 6 which is close to coincidence with a diameter through the innermost portions 29 of the cam grooves of the fiy wheel structure as may be understood by comparing the position of the cam block 59 in Fig. 2 with the position of the cam groovein Fig. 6; considering that the rotation 'is inthe direction of the arrow in Fig. 6. Thus a cam block 59 will actuate the pump plunger M twice in each revolutionwhen each power piston will be at the inner end of its stroke under simplified by avoidance of packed relatively movable parts. This also is true ofthe connections 99 for the water jacket 3i partially shown in Fig. 6 and understood to lead to a suitable water supply.

It will be understood that modifications may occur in the construction and operation of my improved engine; and therefore I am not limited to the precise disclosure herein, but what I claim as new and desire to secure by Letters Patent is:

1. In a rotary engine, a cam, a power cylinder, two opposed pistons in said cylinder having a combustion space in the cylinder between them, the cylinder having inlet and exhaust ports uncovered by outward movement of the pistons, two air compression cylinders each with a piston therein, the cam being mounted for rotation, means operatively engaging the cam with both power pistons and both compression pistons at intervals of ninety degrees of the cycle, the cam being of a configuration to produce two inward and two outward movements of the compression pistons during each revolution, the actuation to compress air occurring during the power stroke of the power pistons, the air compression cylinders communicating with the inlet port to deliver air under pressure for scavenging longitudinally of the power cylinder when the power pistons reach the end of their stroke, and means to supply fuel to the combustion space between the power pistons.

2. An internal combustion engine having a fixed power cylinder provided with inlet and outlet ports, twopistons reciprocating oppositely within said cylinder and adapted to uncover said ports near their point of greatest distance from each other, a cam member rotatable on an axis at right angles to said cylinder and carrying a cam symmetrical with respect to its axis of rotation, means on each power piston engaging said cam to cause rotation of said cam member I on outward movement of the pistons, air compression cylinders communicating with said inlet port and each having a piston therein provided with means engaging the said cam at substantially ninety degrees of its cycle from its engagement with a power piston for actuating said compression pistons, and means actuated by the rotary cam member to force fuel into the power cylinder between the power pistons, the arrangement being such that when the ports of the power cylinder are open, air compressed by the compression pistons will pass longitudinally of the combustion space of the power cylinder to scavenge products of combustion, the air remaining after the closing of the ports will be compressed by the power cylinders, and fuel will cylinders, a cam upon the cam member sym} metrical with respect to its axis of rotation, means on the outer end of each piston in operative engagement with said cam, the shape of the cam and the engagements of the pistons therewith being such as to cause equal and opposite inward movement of the air compression pistons during equal and opposite outward movement of the power pistons for one-fourth of a revolution of the cam member, followed by equal and opposite outward movement of the air compression pistons during equal and opposite inward movement of the power pistons for the next one-v fourth of a revolution of the cam member, the power cylinder having an inlet port for compressed air uncovered by one of the power pistons near its limit of outward travel, and an outlet port for products of combustion uncovered by the other power piston near its limit of outward travel, both air compression cylinders communieating with said inlet port whereby when the power pistons reach their outer limit of travel, air from the compression cylinders will enter the inlet port to scavenge the power cylinder toward the outlet port, and means for supplying fuel to the combustion space in the cylinder between the power pistons.

FRANK J. FETTE.

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