US 3359864 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Dec. 26, .1967 H. H. HAMLIN BARREL ENGINE HAVING FORCED LUBRICATION Filed April 29, 1966 i 2 Sheets-Sheet 1 IN VENTOR. HALLgY H. HAMLIN a M Arr'ys Dec. 26, 1967 HAMUN 3,359,864
BARREL ENGINE HAVING FORCED LUBRICATION Filed April 29, 1966 2 Sheets-Sheet 2 2 -N 58 a U l 6 Fig. C
INV EN TOR. HALLEY H. HAMLIN United States Patent 3,359,864 BARREL ENGINE HAVING FORCED LUBRICATION Halley H. Hamlin, Lyndhurst, Ohio, assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Filed Apr. 29, 1966, Ser. No. 547,080 4 Claims. (Cl. 91-175) The present invention relates to a barrel engine and more particularly to a barrel engine having improved means for lubricating the various internal parts.
A barrel engine is an engine that has a plurality of pistons and cylinder assemblies having their stroke axes parallel to and symmetrically disposed to a power output shaft. The pistons coact with a wobble plate on the output shaft so as to impart rotary motion to the shaft in response to staggered linear reciprocation of pistons in their respective cylinders.
Barrel engines may find application in many fields, both commercial and military, and one important military application for a barrel engine is that of a propulsion unit for naval torpedoes. One heretofore known barrel engine specifically adaptable for use as a prime mover for naval torpedoes is disclosed in the present inventors U.S. Patent 3,151,527, entitled, Barrel Engine, which issued October 6, 1964.
The barrel engine of the above-mentioned patent provides torque balanced contra-rotating propellers for propelling a torpedo through water. Torque balance is required since a lack of it would impose a resisting torque on the torpedo body and cause the torpedo to roll to one side. A permanent inclination of the torpedo is very undesirable as it will interfere with the steering controls. An outer housing and a hollow inner shaft are co axially mounted relative to each other and adapted to establish relative rotation. A fluid pressure inlet, through which hot gas flows, is positioned coaxially wit-h respect to the inner shaft. The motive power assembly includes a plurality of pistons reciprocally mounted in the housing with their stroke axes p'anallel to the axial center of rotation. The motive power assembly is constructed and arranged to translate the fluid pressure into an axial force component. A wobble plate conversion assembly is mounted to the inner shaft for converting the reoiprocatory substantially linear motion of the pistons into rotary motion. The outer housing is rotated in an opposite direction to the inner shaft solely by virtue of the reaction to the rotation of the inner shaft.
Lubrication of the engine of the above-mentioned patent is accomplished by a quantity of lubricant that is contained within the engine casing. By action of the wobble plate and the reciprocating motion of the pistons, the lubricant is rapidly turned and comes into contact with the pistons and other internal parts whereby heat is removed by contact. A vent tube extends radially i'nwardly from the cylindrical wall of the inner shaft to its axial center thereby providing a flow connection between the casing and the interior of the hollow shaft.
As the size of torpedoes become bigger, larger size engines are required which dissipate huge quantities of heat into the engine structure. Accordingly, the lubrication, and resulting cooling, by the splash method is not adequate for the larger size engines. 4 I I The present invention provides improved mechanism and structure for lubricating and cooling a barrel engine. A quantity of lubricating oil is provided in an engine crankcase and is pumped from the crankcake to an external oil cooler. The cooled oil is delivered to a distribution ring and then to a plurality of nozzles that are provided one each in each piston. Each nozzle directs oil against the inner surface of the piston head on which 3,359,864 Patented Dec. 26, 1967 ice it is provided. The oil then leaves each piston through a plurality of openings in the base of each nozzle and passes over the piston rollers thereby lubricating these rotating parts. The oil is then returned to the crankcase and recirculated. The crankcase is maintained at a pressure equal to the pressure of the exhaust by providing an interconnecting vent line between the highest point in the crankcase and a hollow shaft through which gases are exhausted.
It is therefore a general object of the present invention to provide improved lubrication for a barrel engine.
Another object of the present invention is to provide improved means for cooling the pistons of a barrel engine.
Still another object of the present invention is to provide an improved crank-case vent for a barrel engine for equalizing the pressure in the engine crankcase with the pressure in the engine exhaust.
Other objects and advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIGURE 1 is a longitudinal partial sectional view of the aft section of a torpedo;
FIGURE 2 is a partial sectional view of a barrel engine used to propel a torpedo; and
FIGURE 3 is a sectional view taken on line 33 of FIGURE 2 and showing a nozzle.
Referring now to the drawings, and particularly to FIGURE 1, there is shown an aft-section of a torpedo housing 11 in which a barrel engine 12 is st-ationarily mounted and drives a pair of contra-rotating propellers 13 and 14. Hot gas, or other suitable fluid, flows from a combustion chamber into barrel engine 12 where it is distributed to a plurality of cylinders by a rotary valve assembly. The gas drives pistons in the cylinders and the reciprocating motion of the pistons is converted into rotary motion by means of a cam that is attached to and drives a hollow shaft 15. Propeller 13 is provided on the end of hollow shaft 15 and is driven thereby, and a second hollow shaft 16 is concentrically mounted around hollow shaft 15 and is driven in a contra-rotating direction relative to the direction of rotation of hollow shaft 15. Propeller 14 is attached to the outer end of hollow shaft 16.
Referring now to FIGURE 2 of the drawings, hollow shaft 15 is rotatably mounted within engine housing 17 by means of radial bearing 18 and thrust bearing 19. A cam 21 and a spur gear 22 are attached to shaft 15 by key 23 and are rotatable therewith. A rotary valve 24, having an inlet port 25 and an exhaust port 26, is rotatably mounted within housing 17 and is attached to the inner end of hollow shaft 15. Exhaust port 26 communicates with the bore of hollow shaft 15 and exhaust products passing through port 26 pass into hollow shaft 15 and then are expelled into the air, or into the sea.
Six hollow cylinders 27 are positioned in a circular array about the central axis of housing 17, and the central axis of each cylinder is substantially parallel to the central axis of housing 17. A cylinder liner 28 is provided in each cylinder, and each cylinder liner 28 is positioned in the end of the cylinder 27 through which hot gases enter. Each cylinder liner 28 is provided with channels 29 through which a cooling fluid may be circulated. A piston 31 is provided in each cylinder 27 and a first roller 32 is attached to one end of piston 31 by means of a shaft 33. Rollers 32 engage the top surface 34 of cam 21 and a second roller 35 is attached to each piston 31 by means of shaft 36 and engages the bottom surface 37 of cam 21. When hot gases enter into each cylinder 27 through passageway 38, these hot gases move pistons 31 outwardly and rollers 32 apply a driving force against cam 21 thereby causing cam 21 to be rotated. As cam 21 is keyed to hollow shaft 15, rotation of cam 21 causes hollow shaft 15 to be rotated, which, in turn causes gear 22 to be rotated. Gear 22 meshes with gears 41 and 42 which are driven when shaft 15 is rotated. Gear 41, which is attached to shaft 43, drives gear train 44 which rotates shaft 16 in a contra-rotation direction relative to the direction of rotation of shaft 15. Gear 42 is attached to shaft 45 which drives oil pump 46.
A quantity of lubricating oil 47 is provided in crankcase 48 and is circulated by pump 46. Lubricating oil 47 enters pump 46 through passageway 49 and is then pumped through conduit 51 to oil cooler 52. The cooled oil is returned to the engine through conduit 53 and the oil is delivered to distribution annulus 54. Each cylinder wall has an orifice 55 through which the oil passes from distribution annulus 54 into slot 56 formed in each piston. A nozzle 57 is provided in each piston 31 and passageway 59 connects slot 56 and nozzle 57. Nozzle 57 directs oil against the inner surface of the piston head and cools the piston by transferring the heat to the oil. The oil then leaves the piston through a plurality of openings 58 that are provided in the base of nozzle 57, as best shown in FIGURE 3 of the drawings. The oil then passes over rollers 32 and 35 thereby providing lubrication to these elements, and then the oil is returned to crankcase 48 for re-circulation.
A vent pipe 61 is provided to maintain the pressure of the crankcase 48 at a pressure equal to the pressure in the exhaust. As the engine is normally operated wit-h shaft 15 in a horizonal position, vent pipe 61 is located in a high position in the crankcase with its open end as far removed as possible from the moving parts of the engine. By being located in this position, there is very little oil entrainment and the gas content of the crankcase can be withdrawn at a rapid rate by a sudden reduction of pressure in the exhaust, without loss of lubricating oil 47. Vent pipe 61 connects with passageway 62 in the engine cylinder block and orifice 63 in distribution annulus 54 and communicates with an annular space 64 that surrounds hollow shaft 15. A short tube 65 vents hollow shaft 15 to annular space 64. Cooling water is also exhausted into hollow shaft 15 through holes 66 in shaft 15 and serves to cool the exhaust gases. A portion of the water is vaporized and the remaining portion is thrown centrifugally against the inner wall of hollow shaft 15. As tube 65 exends into the center of hollow shaft 15, little, if any, water enters into tube 65.
In operation, hot gases enter rotary valve 24 from sta tionary nozzle 67 and these hot gases are selectively distributed to cylinders 27 when pistons 31 are in an appropriate position to make a stroke. Outward movement of pistons 31 causes cam 21 to be rotated, and as cam 21 is keyed to hollow shaft 15, shaft 15 is rotated and also shaft 16 is rotated in a contra-rotation direction by gear train 44. During the exhaust stroke of each piston 31, exhaust products are expelled from the respective cylinder 27 through passageway 38, exhaust port 26, and into the bore 68 of rotary valve 24 which communicates with the bore of hollow shaft 15. The exhaust products, along with cooling water, is then expelled to the open. Gear 22, which is keyed to shaft 15, provides the drive for oil pump 46 which pumps lubricating oil 47 from crankcase 48 to oil cooler 52. The cooled oil then flows through conduit 53 to distribution annulus 54 from which the cooled oil is distributed to nozzles 57 that are provided within pistons 31, The nozzles direct the cooled oil against the inner surface of the piston heads and cools the pistons. The oil then returns to the crankcase 48 after passing over rollers 32 and 35 and lubricating these rollers.
It can thus be seen that the present invention provides improved lubrication and cooling means for a barrel engine whereby said engine can be driven by gases which are at an extremely high temperature. Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.
What is claimed is:
1. A barrel engine comprising:
a stationary mounted housing,
a hollow shaft rotatably mounted within said housing,
a plurality of cylinder bores in said housing extending in circular array about said hollow shaft with their axes being parallel thereto,
a plurality of pistons slidably disposed one each in each said cylinder bore, each said piston having a hollow hemispherical head thereon,
cam means fixedly attached to said hollow shaft and in engagement with said pistons whereby said hollow shaft is rotated upon slidable motion of said pistons,
a valve rotatably mounted in said housing having an inlet port and an exhaust port, said inlet port selectively providing a passageway between a fluid source and said cylinder bores, and said exhaust port selectively providing a passageway between said cylinder bores and said hollow shaft,
a quantity of lubricating oil in said housing,
an oil distribution annulus within said housing for distributing said quantity of lubricating oil,
a plurality of oil nozzles communicating with said oil distribution annulus, said nozzles being attached one each to each said piston and adaptable for directing said liubricating oil against the inner surface of said hemispherical heads of said pistons, and
means for pumping said lubricating oil from said housing to said distribution annulus.
2. A barrel engine as set forth in claim 1 having means for cooling said quantity of lubricating oil.
3. A barrel engine as set forth in claim 1 having a second hollow shaft concentrically mounted about said first hollow shaft and having means for rotating said second hollow shaft in a contra-rotation direction relative to the direction of rotation of said first hollow shaft.
4. A barrel engine as set forth in claim 1 wherein first and second rollers are rotatably attached to each said piston, said rollers engaging said cams means.
References Cited UNITED STATES PATENTS 1,714,145 5/1929 Sperry 92l92.9 1,808,380 6/1931 Royal 123-4135 1,882,632 10/1932 Jaworowski.
1,896,449 2/ 1933 Kreidler 12358 2,678,536 5/1954 Morgan 91-175 2,776,649 1/ 1957 Fenske.
3,105,415 10/1963 De Muth.
3,151,527 10/1964 Hamlin.
3,151,528 10/1964 Eastman 91l75 3,194,011 7/1965 Chaney.
EDGAR W. GEOGHEGAN, Primary Examiner, PAU E- MASLOUSKY, Examiner.