US2436729A - Construction of internal-combustion engines - Google Patents

Description

E. P. PAXMAN 2,436,729 CONSTRUCTION OF IVNTERNAL-COMBUSTIQN EG'INES y' I Feb. 24, 194s.

Filed June' 2 6, 1944 6 Sheets-sheet 1 www i E nventear.

Feb. 24, v194s. E.' P. PMMAN- ,2,436,729

CONSTRUCTION OF INTE'RNAL-COMBUSTION ENGINES` Filed June` 26, 1944 6 lSlLleecs-Sheec 2 I FV/S ' v eInventor Attorney s Feb. 24, 1948. f E. P. PAXMAN 436,729

CONSTRUCTION OF INTERNAL-CGMBUSTION EGINES Feb. 24, 194. E. P. PAXMAN CONSTRUCTION 0F INTERNAL-COMBUSTION ENGINES Filed June 26', 1944 e sheets-sheet 4 E. P. PAXMAN CONSTRUCTION OF INTERNAL-COMBUSTION ENGINES Reb. 24A 1948.

Filed June 26.1944

[n ventor 'mmv om A Horney Patented Feb. 24, 1948 UNITED STATES PATENT OFFICE TION ENGINES Edward Philip Paxman, Colchester, England Application June 26, 1944, Serial No. 542,174 In Great Britain March 10, 1943 This invention relates to multi-cylinder internal combustion engines and more particularly tothe Diesel type, and has for its object to provide improvements in the design of such engines in order to simplify and expedite manufacture and assembly.

In the production of engines of the kind above indicated it has been common practice to form each cylinder block as a single casting but owing to the necessity for providing supports for the cylinder liners, mounting for the cam shaft and accessory parts and water cooling spaces, the joint face between cylinder block and crank case is irregular and requires a number of separate and often complex and diicult operations to machine its co-operating surfaces. Further complex and accurate machining is necessary to secure exact alignment between various components often involving diiicult and slow procedure.

In a prior Pat, No. 2,429,105, granted October 14, 1947, a mode of construction has been de- A scribed designed to avoid the difficulties described in the preceding paragraph in the manufacture of internal combustion engines of the kind Wherein two banks of cylinders are arranged in mutually inclined positions on a common crank case, and the present invention provides an extension of the said prior invention to the construction of vertical engines.

With a view to extending the utility of the prior invention the present .invention provides for the unitary components therein described to be employed in engines of the vertical type, thereby enabling engines for -dierent purposes to be simply and expeditiously constructed from standard units While the specialised machining and alignment work is reduced to the minimum.

According to the invention a multi-cylinder internal combustion engine of the vertical type is provided including a crank case having plane uninterrupted joint faces formed thereon, cylinder blocks adapted to be bolted in position thereon, a cam box assembly also adapted to be bolted in position in said crank case and cylinder head 3 Claims. (Cl. 12S-195) units having plane uninterrupted joint faces central joint face, cylinder blocks adapted to be mounted on said central joint face, a cam box adapted to be mounted on the side joint face and cylinder head units adapted to be mounted on the cylinder blocks, said cylinder blocks, cam box and cylinder head units all being formed as sub-assemblies prior to the assembly of the engine and all joint faces being formed each with its component parts lying in a common plane.

Reference will now be made to the accompanying drawings which illustrate an example of a construction according to the invention, and in which:

Fig. 1 is a cross sectional elevation taken through a six-cylinder engine,

Fig. 2 is a side elevation of a cylinder block for the engine shown in Fig. 1,

Fig. 3 is a sectional elevation of the cylinder block taken on the line C-C, Fig. 2,

Fig. 4 is a sectional plan of the cylinder block shown in Figs. 2 and 3,

Fig. 5 is a sectional plan of the cylinder head unit for the engine shown in Fig. 1, and

Fig. 6 is a cross sectional elevation of the cylinder head unit taken on the line D-D of Fig. 5.

In the construction illustrated, the'engine is formed with cylinder blocks (shown in detail in Figs. 2 to 4) each comprising three cylinders shown in Fig. 2, an individual cylinder being indicated at 3 in Fig. 1. By dividing the cylinders into separate blocks in this manner, the Weight' to be shifted for each successive machining operation to be performed and the size of machine required arel considerably less than under former practice. The base of each cylinder block is formed by a number of surfaces all lying in one plane indicated at 4 in Fig. 1, which renders the machining of such surfaces to form the component parts of a common joint face adapted to co-operate with a similarly formed joint face on the crank case, a simple operation requiring no intermediate changes in position during the machining operation. The upper surfaces of each cylinder block also lie in one plane indicated `at 5 in Fig. 1, so that a single machining operation forms them into the component parts of a common joint face on which seats the joint face of the cylinder head unit 6.

To enable the two adjacent cylinder blocks to be connected, each is formed with apertured lugs l and 2 at its ends (see Figs, 2 and 3) which lie side by side on assembly and are connected by bolts passed through the apertures l. The lugs are formed at each end of the cylinder block so that any block is capable of use for either end of an engine and does not require to be specially formed. In the recesses between the cylinders, bosses 8 are formed through which pass bolts 9 whose lower ends engage recesses l formed in the upper part of a crank case Ii whereby the cylinder blocks as complete assemblies are secured in their operative positions upon the ,said crank case. Fig. 4 is a sectional plan of Xthe .cylinder block and shows it to .be formed as a single casting with interconnected water jackets l 2 having water supply connections I3 and I4. The cooling water circulates from the jackets l2 through ports 62 and passages "63 into the water spaces 6A! of the cylinder head units 6. From these units the water leaves by Water outlet manifolds 65 which may ,also be utilised to cool the exhaust manifold 65 audits branches.

Figure 4 also shows the positions of the 'bosses 8 which, being disposed in the recesses Ibetween the individual cylinders 3, cause no projections beyond .the main outer walls of theV cylinder block.

The crank .case il .consists of .a .single casting., and Reform-comprises essentially four 'longitudinalgirders indicated at i5, IF, ifi and le in Fig. .1.. These giilders 'are connected at intervals in the length .of the crank ,case ,by a number of webs having substantially radialstrengthening .ribs le, said webs lying in planes at .right angles to the axis ,of the .crank shaft .2t and .being .reinforced by additional ribs 2i at the base to .take the forces d ue to the combustion in the .cylinder .and to ,the reciprocal-,mg and rotating masses of the pistons, rods, bearings and crank shaft. The .said reinforcements .include 1011s bolts 22 which extend completely through .the base .of .the crank .case from Side -to side. The 4base of the crank case is recessed at 23 to receive intermediate bearing elements 2s which support .the under side of .the crank shaft and through `the .bolts ..22 also pass. The gil-ders ,I .and le Vat the top of .the crank case are machined to form .a joint face at 2 5 (on which the ioint faces e of the .cylinder blocks seat, and the oi-nt face 2.5 is formed with apertures ,i2- 6 through which proiect the cylinder liners 2t andthe connecting rods ,2.3 `ci .the pistons 29. E [he upper surface of the ggirder It is also formed with la face at 3D lying all in one plane and inclined downwardly andoutwardly from the centraljoint f ace 25.

.In engines of the general character to which the present invention applies it has been the common practceto form a camshaft housing integral with the `main casi-ig tot casting.. This practice not oniy possesses the disadvantage that a heavy .and unwieidy casting is necessary, but it provides complexities in machining and assembly which add greatly to the .time occupied .in construction .and assembly amd necessitates large proportion of skilled labour to carry @et 'the Operations 116.065" Sary.

one arrangement above .described whereby .a iointiace te is formed .at ione side of the vcylinders provides a clear surf-.ace upon the crank @case which is ntiiised for the disposition of a cam box 31 which 4extends completely ralong the top of the crank case and at .one side thereof. This pain box, which is constructed and` arranged prefer.- ably as described in .the'prior Patent No. 2,429,106, granted October 14, 194']J ,contains the cam shaft and rockers, and mounted .upon its cover are the fuel pumps, timing gear Vand governors.. This assembly after completion independently is placed in position upon the joint face 3c 4on the crank ease, and is held in .position by studs 32 which pass Jthrough the cover 3e of the cam box .and

cam shaft bearings intermediate with studs which serve to retain the coverl in place. This cover with the components mounted upon it can be removed to allow complete access to be obtained to the cam shaft without disturbing other parts of the engine` The arrangement permits of an overhang of the cam box at one end of the engine and it eonly vneeds aligning at ,one end Where the timing .gear is situated. The above described disposition of the cam box and the parts carried iby it is facilitated by the arrangement of the ...cylinder .blQQlS whose walls are without substantial projections, the heads of the bolts 9 for xing the cylinder blocks to the crank case being conveniently arranged within recesses as already described.

'To enabie the crank case to be formed as above described, specific relative proportions between the :height of the crank case at its outer sides and of the individual cylinders are necessary. For this purpose the .height of veach cylinder A.9, is reduced only .to such an extent .that .the water cooling space l2 extending .substantially to .the point .of junction with .the ,crank case provides water cooling for the A.piston pressure rings at ,the bottom of the piston stroke. The reduction of cylinder length vinvolves vthe use of the cylinder liner 2.7 which yprojects a certain distance into the crank case Aas shown in Fig. 1 :and which may be reinforced near ,its v:outer end, for example, by a clamping ring ,34 to prevent damage .to the liner ..2.1 if struck .by the connecting rod ,28 .during assembly or dismantling operations.

To enable connecting .rods and pistons to be removed when necessary the ,Sides of the .crank case are vprovided with-openings normally .covered by doors .3.5 andthe vertical height .of these .openngswhich .must vbe suiicieni', to enable a piston and connecting rod :to be inserted or withdrawn, determines the minimum height between the upper and lower girder components .I5 and l1 or `I6 and i3 .at each side of the crank case .and the positions -of them.

Each cylinder block is provided with a cylinder head `unit 46 which is formed -independently as .a subassembly .complete with valves., valve-.actus ating gear, air cleaners, combustion chambers, injectors and other accessories vin readiness for at tachment to .the cylinder block by seating upon the joint face 5. Fig. 5 shows .a plan of one of the cylinder head units .and includes .bolts 36 by which this unit is secured in position on the cylinder block, these bolts engaging screw-threaded sockets formed in the top face of the cylinder block. Two .kof these .bolts are also shown in elevation 6. Fig. 5 also .shows the ai-r inlets 31, inlet valve spaces 38, .combustion chamber .39, injector socket 46, exhaust valve spaces 4I and exhaust passages 42. The .cylinder head unit is further illustrated in Fig. 1 which includes the air cleaners 43, one of the exhaust valves ,44 and a passage i5 through which passes one of the valve `actuating push rods 10 operated from the cam .box 3l. At 4.6 is one of the tubular sockets shown .also in ligl 6 through which -pass the securing bolts 36,

The engine assembly is completed by a valve cover unit .which contains the valve rockersd and their accessory parts and has a lower Vjoint face indicated at 33a, Fig. 1, the vsurfaces of which lie all in one plane .and which is adapted to seat on a corresponding joint face formed `on the upper part of the `cylinder head unit t,

A iur-ther simplification .in manufacture ,is

eifected by avoiding the necessity for accurate alignment between the apertures in the cam box 3i and the cylinder head unit 6 through which pass the push rods 10. These apertures are made sufficiently large to allow free passage and angular displacement of the push rods, and each pair of apertures in the cam box and cylinder head respectively is connected by a iexible sleeve 49 constructed according to prior Pat. No. 2,397,882, granted April 2, 1946, and adapted to be sprung into position after the main components of the engine have been assembled.

Engines constructed as above described possess the advantage that they can be manufactured with the minimum of difliculty. The crank case H, which is the largest component, can be machined to form the joint faces `and bored to receive the crank shaft bearings by straight line operations which do not involve any changes in position of the crank case during machining which would require heavy machinery. The remaining components, namely, the cylinder blocks, cylinder head units and valve cover units are relatively small, and consequently easy to manipulate, but the reduction in the number of consecutive machining operations due to the employment of joint faces whose components lie all in one plane, and the elimination of aligning operations requiring skilled labour on assembly, greatly reduce the time occupied in the completion of an engine.

In assembling an engine as above described many of the component units employed, such as cylinder blocks, cylinder head units and cam box, can be of the same design as those described in said prior Pat. No. 2,429,105.

I claim:

1. An internal combustion engine of the type having a row of cylinders disposed vertically above a crank shaft, comprising a crank case constituted by a plurality of interconnected longitudinal girders having thereon a joint face situated centrally of the width of the crank case and lying in a horizontal plane and a second joint face at one side of said centrally situated joint face and lying in an inclined plane,

cylinder blocks adapted to be mounted on said centrally situated joint face, a cam box adapted to be mounted on said second joint face, and cylinder head units adapted to be mounted on the cylinder blocks, said cylinder blocks, cam box and cylinder head units all being formed as sub-assemblies prior to the assembly of the engine, and all joint faces between the crank case, cylinder blocks and cylinder head units being formed each with its component parts lying in a. common horizontal plane.

2. An internal combustion engine as dened in claim 1, including valve cover units adapted to be mounted onthe respective cylinder head units and having joint faces each formed with its component parts lying in a common horizon tal plane, said cylinder blocks, cylinder head units and valve cover units comprising sub-assemblies superimposed one upon another and on said horizontal centrally situated joint face on said crank case.

3. An internal combustion engine as dened in claim l, wherein said girders comprise a pair of members extending along the upper portion of said crank case, and said centrally situated joint face is formed on the upper surfaces of said girder members and said second joint face is formed at the outer side of one of said girder members.

EDWARD PHILIP PAXMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,007,842 Belknap Nov. 7, 1911 1,332,964 Vincent Mar. 9, 1920 1,404,550 Setz Jan. 24, 1922 1,416,348 Guy May 16, 1922 1,720,625 Chorlton July 9, 1929 1,900,587 Schutzniedrig Mar. 7, 1933 2,018,612 Good et al. Oct. 22, 1935 2,030,995 Loeler Feb. 18, 1936

Images