US 3521613 A
Abstract available in
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Description (OCR text may contain errors)
July 28, .1970
Filed Sept. 17, 1968 A. CELL] ENGINE WITH DIE-CAST STATIC PARTS 6 Sheets-Sheet 1 lZZ INVENTOR.
ALDO CEL.l- I BY ATTORNEYS July 28, 1970 A. CELL! ENGINE WITH DIE-CAST STATIC PARTS 6 Sheets$heet 2 Filed Sept. 17, 1968 INVENTOR.
ALDO CELLI ATTORNEYS July 28, 1970 A. CELLI ENGINE WITH DIE-CAST STATIC PARTS 6 Sheets-Sheet 5 Filed Sept. 17, 1968 6 6 7 7 w m R. l 011 I 1 TL 11 1 NL a 2 1! 1 We m m c 7 V I O l I H w l O n mm A 8 1 L e I 5 AG 0/ O z o 5 o 0 X #:H k i x o a I J m I- I I e 8 w v w a 1 T:
@m da ATTORNEYS July 28, 1970 CE ENGINE WITH DIE-CAST STATIC PARTS 6 Sheets-Sheet 4.
Filed Sept. 17, 1968 INVENTOR.
' A L DO C E LL ATTORNEYS July 28, 1970 A. CELLI ENGINE WITH DIE-CAST STATIC PARTS 6 Sheets-Sheet 5 Filed Sept. 17, 1968 INVENTOR.
ALDO CELLI ATTORNEYS United States Patent 3,521,613 ENGINE WITH DIE-CAST STATIC PARTS Aldo Celli, 601 Fisher Bldg., Detroit, Mich. 48202 Filed Sept. 17, 1968, Ser. No. 760,160 Int. Cl. F02f 7/00; F01] 1/00 US. Cl. 123195 20 Claims ABSTRACT OF THE DISCLOSURE An internal combustion engine of the liquid-cooled type wherein the static parts of the engine are designed to be made as die castings. The engine includes a crankcase with water jacketed cylinder castings individually mounted thereon. The valve timing mechanism is enclosed in a cast housing supported above the cylinders on a pair of brackets extending upwardly from the opposite ends of the crankcase. The interior of the crankcase is formed with a plurality of partition walls centrally apertured to receive bearing discs in which the crankshaft is journalled. The bearing discs are clamped in position in the partition walls by bolts extending transversely through the crankcase to impart rigidity to the entire crankcase assembly.
This invention relates to an internal combustion engine and more particularly to the design and arrangement of the static parts of a liquid-cooled, four-cycle, internal combustion engine.
Present day practice in the automotive industry in the manufacture of liquid-cooled, four-cycle engines involves the fabrication of many of the static parts of the engine as castings made from sand molds, shell molds or permanent molds. The use of such castings, particularly sand mold castings, results in an engine which is relatively heavy and which, because of the necessarily relatively slow production rate and the extensive machinin required on such castings, renders such engines unnecessarily costly.
It has been recognized that such engines can be made lighter and less costly if the static parts can be die cast. Die-cast engine blocks have been produced with some degree of success but their use has not been widespread, particularly in the automotive industry, because, unless the industry can convert entirely to die casting of all the static parts of an engine, a partial conversion to die-cast parts for the engine is not economically justified.
It is an object of this invention to provide a liquidcooled, four-cycle engine of light weight and which can be manufactured economically.
More specifically, the invention has for its object the provision of a liquid-cooled, four-cycle engine the static parts of which are designed and arranged so that they can be die cast.
Other features and objects of the present invention will become apparent from the following description and drawings in which:
FIG. 1 is a vertical sectional view of an engine according to the present invention taken generally along the line 11 in FIG. 4 and with parts broken away.
FIG. 2 is a sectional view along the line 22 in FIG. 1.
FIG. 3 is a sectional view along the line 3-3 in FIG. 1.
FIG. 4 is a longitudinal sectional view of the engine taken generally along the line 4-4 in FIG. 1.
FIG. 5 is a sectional view along the line 5-5 in FIG. 4.
FIG. 6 is a front end view of the engine with parts broken away.
FIG. 7 is a sectional view taken generally along the line 77 in FIG. 6.
FIG. 8 is a sectional view taken generally along the line 88 in FIG. 7.
FIG. 9 is a sectional view along the line 9-9 in FIG. 8.
3,521 ,613 Patented July 28, 1970 i CC FIG. 10 is a sectional view along the line 10--10 in FIG. 3.
FIG. 11 is a sectional view generally along the line 11-11 in FIG. 1.
Referring first to FIG. 1, the engine includes a crankcase 10 formed as a die casting and having two rows of cylinder extensions 12 cast integrally with the top wall thereof. The two rows of extensions 12 are inclined at a narrow V and are staggered as shown in FIG. 11. On the upper face of each cylinder extension 12 there is secured a die-cast cylinder 14. Cylinders 14 have inner linings 16 cast bonded to the cylindrical wall 18 thereof. Each cylinder 14 is piloted in its respective cylinder extension 12 by the extended liner 16 and is mounted on the crankcase by studs 20 threaded into lugs 22 (FIG. 11) over the ends of which nuts 24 are threaded. Within the bore formed by each liner 16 there is arranged a piston 26 which is connected by a connecting rod 28 to a crankshaft 30 journalled in crankcase 10.
Each cylinder casting 14 is formed with a top wall or head 32 adjacent its upper end and each head 32 is formed with an inlet port 34, an outlet port 36 and a combustion chamber recess 38. Around each inlet port 34 there is integrally cast an inlet pipe 40 adapted for connection with an inlet manifold 42. Around each outlet port 36 there is integrally cast an outlet pipe 44 adapted for connection with an exhaust manifold 46. Each cylinder casting 14 is surrounded by a cap casting 48 which is spaced from the side wall 18 of cylinder 14 and forms a water jacket chamber 50 around each cylinder. Cap casting 48 is press fitted at its lower end over a shoulder 52 adjacent the lower end of casting 14 and is press fitted at its upper end over a shoulder 54 formed on a circular flange 56 cast integrally with cylinder 14 above the head 32. Suitable seals are provided for rendering these joints liquid tight. Each cylinder 14 is also formed with a recessed boss 58 adapted for reception of an ignition device such as a spark plug 60. Each inlet manifold 42 accommodates a fuel injector 61 for admitting fuel to the combustion chamber of each cylinder. In place of fuel injectors one or more carburetors may be employed.
Inlet and exhaust ports 34, 36, respectively, are controlled by valves 62 the stems of which extend upwardly through sleeves 64 press fitted into bosses '66 which are cast integrally with cylinder castings 1-4. The valve guide bosses 66 protrude upwardly from flange 56 and extend through openings 68 in the lower die-cast section 70 of a valve train housing 72. Oil leakage through openings 68 is prevented by rubber boots 69. Valve train housing 72 also has a die-cast upper section 74 which is secured to the lower section 70 by studs 76. A gasket 78 is provided between the adjoining faces of sections 70 and 74 of the valve train housing to prevent leakage of oil from the housing. Upper section 74 of housing 72 is formed with bearing sockets 80 at opposite ends and at the center thereof (FIG. 7) in which a camshaft 82 is journalled. In a more or less conventional manner the cam lobes 84 on camshaft 82 are adapted when rotated to engage rocker arms 86 to actuate valves 62. One end of each rocker arm 86 is engaged by a hydraulic backlash adjuster 88- which urges the rocker arm against the cam lobe 84.
Referring now to FIGS. 4, 8 and 11, crankcase 10 has upright brackets 90, 92 cast integrally therewith at the front and rear ends, respectively, thereof. Brackets 90, 92 extend upwardly to a level above top walls 56 of cylinders 14. The lower section 70 of valve train housing 72 is seated at its opposite ends on brackets 90, 92 and is secured thereto by the two pairs of studs 76 at the opposite ends of valve train housing 72. The pair of studs 76 at the central portion of housing 72 merely serve to secure the upper section 74 of housing 72 on the lower section 70 whereas the studs 76 at the opposite ends of the housing (FIG. 7) serve to secure the housing as a whole on brackets 90, 92 and to secure the upper section 74 on the lower section 7 The upper section 74 of housing 72 is formed with flanged opening 93 for receiving a breather cap 94.
Referring now to FIGS. 1, 4 and 8, crankcase is generally rectangularly shaped and has a top wall 95 and side walls 96. An oil pan 98 closes the bottom open side of crankcase 10. The front end of crankcase 10 is fashioned with a circular opening 100 closed by a cover plate 102. The rear end of crankcase 10 is formed with a circular flywheel housing 104 which is centrally apertured as at 106. Internally crankcase 10 is formed with a plurality of transverse partitions 108 which are centrally apertured as at 110 to receive bearing discs 112. Each bearing disc 112 comprises two half sections 114, 116 which, when secured together as by studs 118, form a main bearing 120 within which the bearing portions 122 of crankshaft 30 are seated. The disc sections 114, 116 are arranged on the bearing portions 122 of crankcase 30 before the crankshaft is inserted in crankcase 10' through the opening 100 in the front wall thereof. Each partition 108 includes a pair of spaced side walls which extend transversely of the crankcase from the side walls 96 thereof to the annular boss 128 which defines the circular opening 110 in each partition. Boss 128 at the bottom side of opening 110 is formed as a sleeve 130 which is radially slotted as at 132. A plurality of bolts 134 extend transversely through the side walls 96 of the crankcase between the walls 124 of each partition 108 and each sleeve 130. When the nuts 136 on the ends of bolts 134 are tightened, each bearing disc 112 is firmly clamped within the circular boss 128 on partitions 108 and extreme rigidity is imparted to the crankcase as a whole. For the purpose of locating each bearing disc 112 in its proper rotative position within the apertures 110 dowel pins 138 are provided. Thus the crankshaft is solidly supported in crankcase 10 at each of its bearing portions 122 by the cross walls on partitions 108. The spaces between partitions 108 accommodate the counterweights 140 on the crankshaft and the connecting rods 28.
A flywheel 142 is secured to the rear end of crankshaft 30 as by screws 144. The flywheel has a series of permanent magnets 14 6 mounted thereon to form an alternator. Starting of the engine is accomplished by means of a conventional starter 148 (FIGS. 7 and 11) which is mounted on crankcase 10 and flywheel housing 104.
On the front end of crankshaft 30 exteriorly of cover plate 102 there is keyed a pulley 150* engaged by a timing belt 152 and a second pulley 154 engaged by a belt 156. Belt 156 is also trained around a pulley 158 mounted on a cooling fan 1 60. The shaft 162 on which fan is mounted also drives an impeller 164 of a water pump 166. Timing belt 152 extends around a pulley 168 (FIGS. 4 and 7) at the front end of camshaft 82. Timing belt 152 also extends around a third pulley 170 (FIG. 6) which drives a shaft 172. Shaft 172 in turn drives suitable gearing 174 (FIG. 8) for providing a drive to distributor 176, an oil pump 178 and a fuel injection pump 180 (FIGS. 7 and 8), all of which are supported on a side wall of crankcase 10 by a mounting plate 181. The pulleys around which timing belt 152 is trained and water pump 166 are shielded by a cover 182.
Water pump 166 has an inlet duct 184 and an outlet port 186. A pair of branch conduits 188 formed in front bracket 90 extend from outlet port 186 downwardly toward each side of crankcase 10 as shown in FIG. 6 and communicate with cored passageways 190 extending along each side of crankcase 10. As shown in FIG. 1, each cylinder extension 12 formed integrally with the top wall of crankcase 10 has a vertical passageway 192 therein which at its lower end communicates with passageway 194 at the lower end of cylinder casting 14. Passageway 194 communicates with the water jacket chamber 50. As the water is directed upwardly between cylinder casting 14 and cylinder cap casting 48 the cylinder is cooled and the water is directed outwardly of water jacket chamber 50 through an outlet spout 196 formed integrally with cap casting 48. The outlet spouts 196 are connected by hoses 198 to water manifold tubes 200 extending along each side of the engine (FIG. 6). The water manifold tubes 200 connect with a thermostat 202 at the front of the engine which directs the Water either to a radiator (not shown) through an outlet 204 or back to the water pump through a bypass 206. The outlet of the radiator is connected by a hose 208 with the inlet duct 184 of water pipe 166.
Oil pump 178 has an inlet passageway 210 which communicates with a cored passageway 212 in crankcase 10. A conduit 214 extends from screened intake member 216 in oil pan 98 to passageway 212 for supplying oil to the pump. The outlet passageway 218 of pump 178 extends to a cored passageway 220 extending longitudinally along one side of crankcase 10. Branch passageways 222 are designed for supplying oil to bearing discs 112 which in turn, through suitable passageways in the crankshaft, direct oil to the bearings of the crankshaft. Another branch conduit 224 (FIG. 8) extends to a vertical passageway 226 formed in end brack 92 on which the rear end of the valve train housing 72 is supported. At its upper end passageway 226 registers with a longitudinally extending passageway 228 in the lower section 70 of housing 72. Suitable branch passageways communicate with the longitudinally extending passageway 228 for supplying oil to the backlash adjusters 88 and the bearings of camshaft 82. Oil is drained from housing 72 down to the crankcase through a discharge passageway 230 (FIGS. 4 and 11) which is formed in end bracket 90 on which the front end of valve train housing 72 is supported.
The advantages of the above described engine construction are apparent. It will be observed that all the static parts of the engine are ideally suited for die casting. These cast parts, particularly cylinder castings 14 which are the most intricate, are not formed with undercuts and, accordingly, permit straight withdrawal of the metallic cores of the dies. Since the parts can be die cast, the section thickness required to accommodate the stresses encountered are reduced, thus saving on metal costs and making the engine substantially lighter.
Further metal savings are obtained by staggering the cylinders in the two rows as illustrated in FIG. 11, thus shortening the camshaft and the crankshaft and as a result shortening the entire engine. The individual cylinder construction improves heat dissipation due to both liquid cooling of the cylinders and also heat dissipation by radiation from around the entire periphery of each cylinder. The individual cylinder construction minimizes the cost of casting and tooling and also the cost of rejections since only faulty casting represents only one cylinder as distinguished from a cylinder :block containing six cylinders as in the case of a sand casting. The cost of machining the casting is also reduced because of the precision casting techniques involved in die casting and the resultant minimum stop removal required.
The lack of undercut surfaces and blind holes and bores in the castings has the further advantage of enabling impregnation and treatment for other types of surface protection easy to accomplish and to control.
The engine as described herein also has the advantage of eliminating the need for many closely controlled tolerances. Valve train housing 72 is completely isolated from the individual cylinders 14. The manufacturing tolerances at the joint faces of brackets 90, 92 and lower housing section 70 can be relatively large because this will not affect timing. Dimensional variations will be accomodated by the backlash hydraulic valve adjusters 88. The crankshaft-camshaft center line distance is not critical because a slight variation in this distance results only in slightly different inclinations of the rocker arms 86 and this will not affect timing of the engine. Timing of the engine is likewise not affected by a slight variation in the angular disposition of the cylinder axes because the lack of exact coincidence of valve stem center lines and the center of curvature of the rocker arm tips does not appreciably affect valve timing. At most this will cause only a slight variation in rocker arm lever ratios which might produce a slight difference in the valve opening but will not affect valve timing. Manufacturing tolerances of the cylinders, crankcase or the valve train will not affect valve timing because the holes in which the valve stem guides 64 are press fitted will be drilled and reamed in bosses 66 after temporary assembly of the cylinders on the crankcase and and temporary assembly of the valve train housing 72 on brackets 90, 92. This temporary assembly assures exact positioning of the valves relative to the tips of the rocker arms 86 in final assembly of the engine.
1. A liquid-cooled internal combustion engine comprising a crankcase casting having a top wall, a plurality of individual cylinder-forming castings secured to said top Wall, e"ach cylinder casting having a generally cylindrical side .wall and a top wall, said top wall having an intake port and an exhaust port therein, ducts extending upwardly from said intake and exhaust ports, said cylinder casting also having a wall-forming flange spaced above said top wall and connected to said top wall by said ducts and a cylinder cap casting surrounding said cylinder casting, said cylinder cap casting having a side wall spaced radially outwardly from the side wall of the cylinder casting and extending upwardly beyond the top wall of the cylinder casting, means forming a sealed connection between the lower end portion of the cap casting and the lower portion of the cylinder casting and means forming a sealed connection between the upper end portion of the cap casting and said wall-forming flange whereby to form a cooling chamber surrounding the side wall and top wall of each cylinder.
2. An engine as called for in claim 1 wherein said intake and exhaust ports extend upwardly beyond said wallforming flange.
3. An engine as called for in claim 1 including a pair of hollow bosses formed on said wall-forming flange and aligned axially one with said intake port and the other with said exhaust port, valves controlling each of said ports and having stems projecting upwardly through and slideably guided in said hollow bosses.
4. An engine as called for in claim 1 wherein the top wall of said crankcase casting is formed with a plurality of cylindrical extensions projecting upwardly from said top wall, said cylinder castings being mounted on the upper ends of said extensions, a cylinder lining extending axially within each extension and its associated cylinder casting and a piston arranged for reciprocation in said liner.
5. An engine as called for in claim 1 including means forming a coolant passageway extending along each side of the crankcase, each of said cylinder castings having a passageway in the lower portion therein establishing com- .munication between said coolant passageways and the coolant chambers surrounding each cylinder.
6. An engine as called for in claim 5 wherein each cylinder cap casting has a coolant outlet adjacent its upper end.
7. An engine as called for in claim 1 wherein said cylinder castings are arranged on the crankcase in two staggered rows with the axes of the cylinders in one row inclined to the axes of the cylinders in the other row to provide a V arrangement of cylinders.
8. An engine as called for in claim 7 wherein each of said cylinder and cap castings is spaced from the adjacent cylinder and cap castings so that the entire circumferential extent of each cylinder is exposed to the surrounding atmosphere to assist in heat dissipation.
9. An engine as called for in claim 1 including a valve train housing removably supported on said crankcase above said cylinders and independently of said cylinder and cylinder cap castings, valves controlling said intake and exhaust ports of each cylinder, said valves having stems projecting upwardly through said top wall and into said valve train housing, a camshaft journalled in said valve train housing and a rocker arm assembly in said valve train housing operatively interconnecting the stems of said valves and said camshaft.
'10. An engine as called for in claim 9 including a pair of hollow bosses on said wall-forming flange of each cylinder casting and aligned axially one with the intake port and the other with the exhaust port, said valve stems being slideably guided for reciprocation in said bosses.
11. An engine as called for in claim 9 including a support bracket extending upwardly from each'end of the crankcase, said valve train housing being mounted on the upper ends of said support brackets.
12. An engine as called for in claim 9 wherein said valve train housing comprises an upper section and a lower section which are separable, said upper section having a plurality of bearing sockets formed therein and spaced lengthwise thereof, said cam shaft being journalled in said bearing sockets.
13. A liquid-cooled internal combustion engine comprising a crankcase casting having side walls and a top wall, a plurality of individual cylinder-forming castings mounted on the top wall of the crankcase, each cylinder casting having an intake port and an exhaust port and conduits extending upwardly from said ports, a valve train housing supported on said crankcase independently of said cylinder castings, valves controlling said intake and exhaust ports, said valves having stems projecting upwardly from said cylinder castings and into said valve train housing and means within said valve train housing for operating said valves.
14. A liquid-cooled internal combustion engine comprising a crankcase casting having side walls and a top wall, said top wall having a plurality of openings therein, a plurality of individual cylinder-forming castings secured on said top wall one over each of said openings, said crankcase having a purality of transverse partition walls extending between the side walls thereof, eachof said partition walls having a central opening therein, a split bearing disc removably retained in each of said central openings, a crankshaft having main bearing portions journalled in said bearing discs, said crankshafts having cranks thereon, a piston mounted in each cylinder casting for reciprocation and connecting rods connecting each piston with the cranks on the crankshaft.
15. An engine as called for in claim 14 wherein said crankshaft has counterweights thereon extending radially from the axis of rotation of the crankshaft, each of said central openings having a radius at least as large as the radial extent of said counterweights.
16. An engine as called for in claim 15 wherein the crankcase has an end wall provided with an opening sufficient in size to accommodate axial insertion of the crankshaft with the bearing discs mounted thereon.
17. An engine as called for in claim 15 wherein each partition wall has a slot therein extending from the lower edge portion of the wall to the periphery of the central opening therein and means for drawing the edges of said slots toward each other to clamp the bearing discs in said central openings.
18. An engine as called for in claim 17 wherein said last-mentioned means comprise bolts extending between the side walls of the crankcase at each of said partitions.
19. An engine as called for in claim 18 wherein each partition wall comprises a pair of spaced side walls extending inwardly from the side walls of the crankcase and connected by an annular boss extending around the periphery of said central opening.
20. An engine as called for in claim 19 wherein said bolts are disposed between said spaced partition side walls.
References Cited UNITED STATES PATENTS Freyn 92-149 Dolza 92-147 Dolza 123-195 Sampietro et a1. 92-147 Kolbe et a1. 123-4182 WENDELL E. BURNS, Primary Examiner U.S. Cl. X.R.
Herschrnann 123-195 10 92-147, 161, 261; 123-41.81, 9O