WO1987003039A1

WO1987003039A1 - Two stroke diesel engine having complex piston

Info

Publication number: WO1987003039A1
Application number: PCT/KR1987/000001
Authority: WO
Inventors: Dong Myung Kim
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-01-13
Filing date: 1987-01-13
Publication date: 1987-05-21
Anticipated expiration: 1988-07-13
Also published as: KR870007352A; KR890002659B1

Abstract

A unconventional displacement two stroke diesel engine for the improvement of two stroke diesel engine in the respects of lighter weight, smaller size and lower production cost by reducing the number of engine parts by means of giving complex functions (air precompressing, combustion, cooling) to the complex piston (P), which have two pairs of pistons of differential diameters (pistons for combustion chamber (1)(1') and pistons for air precompressing (3)(3')) as a united body, and, which is to be reciprocated in horizontally opposed engine body (E).

Description

DESCRIPTION

TWO_STRO E_DIESEL_E GINE_HAyiNG_COMPLE

TECHNICAL FIELD

This invention is related a unconventional displacement two stroke diesel engine having horizontally opposed combustion system.

BACKGROUND ART

The rational characteristics for judging the quality of an internal combustion engine driven by reciprocating pistons are as follows: 1. lighter weight 2. smaller size 3. lower cost 4. better fuel economy 5. simplicity of operation and control 6. flexibility

(ability to operate over a wide range of speed-road combinations) (Refer. : "The Internal Combustion Engine in Theory and Practice, Volume 2" by Charles Fayette Taylor, 1968, P575-578).

Therefore, in order to develope an engine which meets above char- acteri sties, it will be desirable to reduce the weight and the number of engine parts on the condition that engine-composing keeps perfect performing of engine functions. That is, kinetic energy which is gen¬ erated in the combustion chamber in engine is to be consumed a little during being transmitted to the transmission gear part by circumferen- tial connected parts, and because the surplus kinetic energy except for the energy consumed here is to be used as the power of engine, reducing the friction of engine parts will be the important condition for reducing thermal loss and will also reduce production cost by reducing the number of engine parts. To this aim, various types of piston engine have been developed from long time ago, and, if they couldn't improve the required charac¬ teristics as above, the utilization of that engine would be impossible because of inferior effectiveness and economization. By way of exception, in the case of diesel engine, though it could not be successful in improving in the respects of lighter weight, and smaller size, commercial utilization has been realized by the evaluation of its economization as to fuel consumption. In the case of the diesel engine, increasing power per weight of an engine has been pointed out as a improving point, therefore increasing horse power per unit weight has been the aim for improving.

DISCLOSURE OF INVENTION

This invention is about making to operate an engine by means of complex piston(P) which is composed of two pair of pistons having differential diameter displaying complex functions as a united body. (Refer. Fig. 1) To be more particular, the connecting-rod of conven¬ tional engine can be omitted by means of inducing to rotate crank- shaft by a pair of pistons for the combustion chamber(l)(l'). That is, by the supporter which has the rotation part at the center of it, combining two pairs of pistons as a united piston in order to reduce the bulk of engine, and to improve the performance of diesel engine. This invention has been developed in pursuit of the improvement ^• of the conventional two stroke diesel engine by the reason of preced¬ ing explanation. That is, making diesel engine lighter by means of utilizing the merit of a compact two stroke diesel engine. But there are technical difficulties to do so. Those difficulties are the over-heating problem and inferior changing efficiency of intake air and exhaust in comparison with the four stroke diesel engine. That is why four stroke diesel engines have been made much more than two stroke diesel engines. Therefore excellent functions of cooling and improving the changing efficiency of intake air and exhaust and reduc¬ ing the number of engine parts have been desirable factors for improv- ing by engine makers. On the other hand,- nowadays the application of new ceramic material to diesel engine has been studied actively. Thermal efficiency of ceramic diesel engine is to be improved by the reason of heat resisting and adiabatic combustion effect which can use heat loss by compulsory cooling for the transformation to the kinetic energy of piston. But in that case, the temperature of the inside wall of combustion chamber is to be about 1,000°C, therefore, counterplan for that problem is to be needed because lubricant can be burned in result of the high temperature of the combustion chamber, and it can bring an obstacle to the smooth operation of engine. The purpose of this invention is making a two stroke diesel engine having high power in comparison with engine weight by means of reducing the number of engine parts. To be more particular about this purpose, omitting or minimizing of the external cooling system 5 by means of the cooling air according to the operation of piston can be done.

Another purpose of this invention is to contribute to simplifica¬ tion of engine by means of utilizing kinetic energy of one side piston which is in power stroke to the compression force of the other side LO of piston directly. The major technical measures of this invention are as follows:

(A) Making pistons for combustion chamber(l)(l' ) to reciprocate horizontally as a united body.

(B) Substituting supporter(5)(5' ) for connecting-rod which rotates 15 . the crank-shaft(CS) , and transmitting the kinetic energy of reciprocating to the rotating force by means of connecting the crank-shaft(CS) to the center of the supporter.

(C) Inducing for air precompressing by means of the piston for air precompression(3)(3') which is attached to the piston for

20 combustion chamber(l)(l' ) and performing air surpply and cooling function to the combustion chamber.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a drawing of the complex piston.

Fig. 2 is a drawing of the disassembled of Fig. 1 and slider and 25 bearings.

Fig. 3 is a drawing of the slider and bearings.

Fig. 4 is a sectional drawing of the engine by this invention.

Fig. 5 is a horizontal sectional drawing of Fig. 4.

Fig. 6 is a A-A¹ line sectional drawing of Fig. 4.

30 Fig. 7 is a sectional drawing of air intake tube.

Fig. 8 is a B-B' line sectional drawing of the cutting surface of Fig. 4. 4 -

Fig. 9 is a enlarged sectional drawing of the circumference of slider by this invention.

Fig.10 is a enlarged sectional drawing of the circumference of slider by this invention. Fig.11 is a examplary drawing of another applicated engine by this invention.

Fig.12 is a horizontal sectional drawing of Fig. 11.

Fig.13 is a explanatory drawing of the operation by this invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Further, this invention could be understandable by detailed explanation of practical examples for best mode in connection with appended drawings. Fig. 1 and Fig. 2 are assembled and disassembled drawings of complex piston. As shown in drawings, there are sever.al piston rings(2)(2') around the pistons for combustion chamber(l)(l' ) , and the inside part of pistons for combustion chamber(l)(l') , the expanded pistons for air precompression(3)(3' ) and the piston rings (4)(4') are installed. These pistons(l)(l')(3)(3') are connected to the flat supporter(5)(5'), and its' connection surface is to be formed like stairs. As shown in Fig. 2, piston bodys on both side are arranged as an opposed type, and are to be assembled by jnnecting bolts(7)(7'), and semicircular type bearing(8)(8') are to be kept at the center part of supporter(5)(5'), that is, on inside of the slider holder hole(6), and slider(S) is to be inserted to that hole.

As shown in Fig. 3, slider(S) has its' round contact surface on its' both sides, and, the slider is composed of two sliders' com- ponents(9)(9')which are joined by joint bolts(10)(10' ) , and center of it, there are two inserted crank-pin bearings(12)(12'), and the inner part of slider(S), there is oil (lubricant) pathways(13)(13')(14)(14') with a type of hole or groove. And, Crank-pin bearings(12)(12') have three oil grooves(OA)(OB) (OC), and the oil groove(OA) is divided. And, there are oil pathways (13)(13^l)(14)(14* ) which are connected with above-stated-oil grooves (0A)(0B)(0C) , between the inside contact surface of slider(S) and the out side contact surfaces of slider(S). And, there are two kinds of oil pathways which are the inner part of slider(S), and the first are the oil pathways(14)(14' ) connected between oil groove(OA) and long 5 groove, (a part of oil pathways(14)(14' )) and the second are the oil pathway(13)(13' ) which form "V" type connected to oil grooves(OB)(OC) . (See Fig. 9, 10)

And the purpose of the first is to send oil to the pistons for combustion chamber(l)(l' ) and the pistons for air pracompression

ID. (3)(3' ) , and the second is to lubricate for slider(S) and slider beaπ^'ngs(8)(8').

As shown in Fig. 4, complex piston(P) is installed in the inner part of engine body(E). This engine body(E) is to be formed horizon¬ tally opposed, and bolted by connecting bolts(17)(17' ) with engine

15 blocks(15)(15') which is joined to the same combustion-chamber(F)(F' ). And for the air supply of cylinders(C)(C) , there are several air intake holes(18)(18' ) , and there are air supply rooms(19)(19' ) in circumference of cylinders(C)(C) (See the drawing of cutting surface of the air supply room in Fig.8). This kind of air supply method is

20 well known, and air swirl which is beneficial for mixing of intake air and fuel can be formed.

And there is an oil groove (21 or 21') in inside wall of cylin¬ der, and also there is an oil exhaust hole (20 or 20') which exhausts oil from the oil groove. And there is an air-precompression room

25 (22 or 22') for the operation of the pistons for air-precompression, and at this place, the air-precompressing pipe (23 or 23') which is connected to air tank(T) and check valve (29a or 29a') are installed. (See Fig. 4, 13).

And the intake port which is connected to intake manifold(27) is

30 to be installed at this air-precompression room (22 or 22') and here, another check valve(29)(29') is to be installed. (See Fig. 6, 7)

As shown, there is an -oil groove (21 or 21') in inside wall of the air-precompression room (22 or 22'), and also an oil exhaust hole(24 or 24') is to be connected with this oil groove. (21 or 21')

35 Combustion chamber (F or F') is to be installed at the head part of the both sides, exhaust valve (25 or 25') which is operated by cam (omitted in drawings) and fuel injection nozzle (26 or 26') are to be installed there. (See Fig. 5)

Fig. 4 is the vertical cross-sectional view which contains complex piston(P) of this invention, and Fig. 5 is the horizontal cross-sectional view, and these drawings show the oil supply pathway to the piston for air precompression(3 or 3') and the piston for combustion-chamber(l or 1') through slider(9)(9') and supporter (5)(5') from crank-pin(CR) .

Fig. 6 is the A-A' line cross-sectional view of Fig. 4, and this drawing shows the location of crank-shaft(CS) and supporter(5') and flange of engine body(E), intake manifold(27), throttle valve(28) and air tank(T).

Fig. 7 is the cross sectional view of air intake system. The intake air is absorbed from the open check valve (29 or 29') which is operated by the pressure (or vacuam) of the air precompression room (22 or 22').

Fig. 9 is the cross sectional view of the circumference of slider(S), and it shows the vertical cutting surface which is centered in oil groove(OA) of the crank-pin bearing in Fig. 3. As shown in the drawing, each one of the crank-pin bearings (12)(12') has its' own oil groove. And when the oil groove meets the oil hole of the crank-pin(CR), oil is to be furnished.

And oil pathwa (14 or 14') is connected between the oil groove (OA) and the long groove (a part of oil pathway(14)(14')) of sliders' contact surface, and by the movement of slider(S), oil pathway (14 or 14') is to be connect to oil pathway (5a or 5a') periodically.

Fig. ^"10 shows the cutting surface which is centered in oil groove(OC) of crank-pin bearing (12 or 12'), and oil groove(0B or OC) has its's own oil pathway from the center hollow of crank-pin (See the crank-pin of Fig. 5, Fig. 12). And this "V" type oil pathway (13 or 13') can supply oil between slider(S) and slider bearing (8 or 8') when there is oil pressure in the hollow of crank-pin(CR) .

Fig. 11 and 12 are the cross-sectional views of another practical example which changes the methods of intake and exhaust, and the com- bustion chamber is located in the head of piston for combustion chamber(l or 1') . According to this type, the method of scavenging is the same kind as M.A.N.Co. so, the loop scavenging is to be formed in the cylinder, and air intake port (30 or 30') is to be located inside the exhaust port. According to Fig. 11, the form of the combustion chamber which is installed at the head of the piston for combustion chamber(l or 1') looks half-oval type and in the case of horizontal cutting,, it looks half-semicular type as shown Fig. 12. Therefore, air swirl is to be generated by air concentration to the combustion chamber(31 or31') in compression stroke. Fig.13 shows the operation of air intake and exhaust. This drawing shows also the operation of compressor by this invention. And it also shows the possibility of control of the air compression of air tank(T) by throttle valve(28). And the major operations of the above mentioned invention are the transformation of reciprocating movement of piston to rotation without connecting rod, air supply, lubricating operation, and to be more particular, it is to be as follows:

A. Operation of Movement Transformation by Piston Stroke

Because one pair of the pistons for combustion chamber (1)(1') are to be composed to be opposed as a united body, it operates contrarily by the observation at the crank-shaft(CS). That is, when one side cylinder is compressed by complex piston (P), the other side cylinder will be expanded, and the compres¬ sion process of one side cylinder is to be done from scavenging stroke to compression stroke, and the expansion process of the other side cylinder is to be done from explosion stroke to scavenging stroke (See Fig. 13 (A)(B)).

And when complex piston(P) reciprocate horizontally, slider(S) which is inserted in slider holder hole (6) of suppor- ter (5 or 5') will be reciprocating up and down. And the rota¬ tion of crank-shaft(CS) is to be made by the reciprocal action of these parts. Rotary power of crank-shaft is to be generated after top dead center(T.D.C). Explosion energy which is recieved by complex piston(P) is to be transformed into the rotary power of crank-shaft, and a part of that energy is to be used for the compression power of the other side combustion-chamber, so smooth rotation can be made with the minimum weight of flywheel.

Operation of Air Supply and Cooling

According to the reciprocating of the complex piston, the piston for air precompression inhales air into the air precom- pression room(22)(22') which is in the engine block, and on the contrary, in the case of another side of the air precompression room, compressed air is to be sent to air tank(T) . And this operation is to be done by check valves(29)(29')(29a)(29a'). In the case of Fig. 13 (A), the reduction of air pressure of left air precompression room(22) leads the opening of check valve(29) which is to be opened inside according to the movement of complex piston(P) from left to right, on the contrary, check valve(29a) which is to be opened to air tank(T) is to be closed, so, air movement is to be "air intake tube →- throttle valve(28)→- check valve(29) →-air precompression room(22)". On the contrary_: the increasing of the air pressure of air precompression room (22') which is on the opposite side leads the closing of cheak valve(29') which is to be opened inside, and, on the contrary, it leads the opening of check valve(29a'), so air movement is to be "air precompression room(22') →- check valve(29a') →-air tank(T)", therefore, compression air is to be stored in the air tank.

Fig. 13(B) is about the case in which complex piston(P) move from right to left, and its operation is contrary to the case of the above-mentioned. And, in the case of Fig. 13(A), air is to be sent to air tank(T) through the check valve(29a') and in the case of(B), air is to be sent to air tank(T) through the check valve(29a), therefore air is furnished in e ery stroke.

And the air stored in air tank(T) is to be sent when the air intake hole(18)(18' ) is opened to cylinder by the piston for combustion chamber(l)(l' ) as the result of complex pistons' (P) reciprocating, and, a part of intake air is to be used for the expulsion of the burnt gases, and the surplus air is to be used for the cooling of the cylinder(C)(C ).

And, in the case of the engine which is shown in Fig. 4,5, air swirl is to be generated as shown in Fig. 8 (In the case of this invention, the diameter of the piston for air precompres¬ sion, capacity and pressure of the air tank(T), and the quantity of air supply is to be selected by designing of engine).

Operation of Lubrication

The lubrication system of this invention is to be operated to send oil compulsorily from the oil pump to the hallow of crank-pin preferentially, and then to send to the contact surface of the pistons for combustion chamber(l)(l') and the pistons for air precompression(3)(3' ) with cylinder wall secon¬ darily, and than to exhaust. As shown- in Fig. 5, Fig. 12, there are three oil holes in crank-pin, and one of them is to be connected with oil groove (OA) which is made to divide into two on the inside of crank pin-bearing(12)(12') , and two of them as shown in Fig. 10 are . to be connected to oil groove(OB) and oil groove(OC) which are not divided on the inside of crank pin bearings(12)(12' ) . According to the operation, by the rotation of crank-pin as Fig.9, the place of contact surface is to be changed, so the center oil hole on the surface of crank-pin(CR) is to be connected to the divided oil groove(OA) periodically, therefore, periodically oil is to be sent to the oil pathway(14)(14' ) in slider(S) compulsorily.

To be more particular about the timing, if crank pin(CR) runs in the direction of the arrow shown in the drawing, the time will correspond to the bottom dead center(B.D.C) of the left cylinder, and the top dead center of the right cylinder because the slider is at the center of slider holder hole(6). At this time, the sending of oil from "the center hallow of crank pin(CR) →- the crank pin oil pathway →- the upper oil groove of divided oil groove(OA) →- oil pathway(14') →- oil pathway(5a' )" is to be just before its' stop, (in the case of Fig. 9, oil has been sent during rotating about 140°) and oil sending is to be kept at stop until the oil pathway of the crank pin meets the upper oil groove(OA) of divided oil groove(OA). That is, during the explosion stroke of the right cylinder, oil supply to the wall of cylinder is to be stopped, and oil is to be scraped down to the oil groove(21') by oil ring(la')(5b') for collecting and exhaust operation, and the left side oil system has the same operation. Therefore, the circulation of lubricant to the left and right cylinders and air precompression rooms' cylinder is to be done by the complex piston(P) and oil is to be furnished to cylinders' wal1 when complex piston(P) goes into the cylinder (C)(C) and oil is to be scraped down from the cylinder's wall when complex piston(P) moves back from the cylinders by the oil rings(la)(la')(5b)(5b').

The period of oil pathways' (5a¹) contacting with the long^* groove(14') of slider(s) and the period of crank-pin pathways' contacting with upper oil groove of divided oil groove(OA) are to be controlled by the length of long groove(14') and the occupied rotation angle for contact.

As the above-mentioned, this invention makes the performing of complex functions of the generation of kinetic energy, air supply, cooling, lubrication, and in addition, the inertia force of the complex piston(P) can be utilized for the air compressing force of the other side cylinder when one side piston for combus¬ tion chamber(l) adds rotation force to the crank-shaft(CS) , therefore, the weight of flywheel is to be minimized. And as a result of complex pistons' moving, air is to be precompressed by the piston for air precompression(3)(3' ) , and periodically air supply and scavenging are to be performed, therefore, the effective and compulsory air circulation of a great quantity has the function of cooling for the circumference of the combus¬ tion chamber (F)(F') and this function of cooling can be utilized for the reduction of temperature of ceramic engines combustion chamber.

Claims

1. Two stroke diesel engine having complex piston(P), which is specialized by composing to insert complex piston(P), which have slider(S) that is inserted and slider holder hole(6) at the center of supporter(5)(5' ) which is connected to the expanded pistons for air precompression(3)(3' ) which is inside of the pistons for combustion chamber(l)(l') to make as a united body of a pair of pistons for combustion chamber(l)(l'), to the inner part of engine body(E) which have horizontally-installed cyl i nders (C)(C) at the both sides and air precompression rooms

(22) (22') backside of cyl i nders (C)(C ) and air supply room (19) (19') for the purpose of precompressed air is to be sent compulsorily to cyl i nders (C) (C ) through it.

2. Two stroke diesel engine having complex piston according to claim 1, which has the stair-type supporter for the possibility of being assembled and disassembled, and which has attached semicircular type bearings(8)(8' ) inside its' slider holder hole (6), which is contacted with the slider's(9)(9' ) contact surface.

3. Two stroke diesel engine having complex piston according to claim 1, which has the round surface of its' slider and which is divided into two parts for the possibility of being assembled and disassembled, and having the crank-pin bearing(12)(12' ) which is attached to the inside wall of the center part of the slider(S) .

4. Two stroke diesel engine having complex piston according to claim 1, which is made by joining the engine blocks (15) (15' ) of the engine body(E) that has two same cylinders(C)(C ) for the possibility of being assembled and disassembled, and which has combustion chamber(F)(F' ) that is equipped with exhaust valve (25) (25') and fuel injection nozzle(26)(26' ) at the head part. 5. Two stroke diesel engine having complex piston according to claim 1, which is composed to send compulsorily compressed air by air precompression room(22)(22') through compressed air tube(23)(23') to air tank(T) that is attached to engine body(E), and which is composed to supply the compressed air from the air

_.supply room(19)(19' ) when complex piston(P) opens the air supply hole(18).

6. Two stroke diesel engine having complex piston, according to claim 3, which has slider(S), having penetrated oil pathway (14) (14') from the inscribed surface to the center of both sides, and forming the leading grooves for oil whose directions are contrary at the outside surface of both sides.

7. Two stroke diesel engine having complex piston according to

^• claim 4, which is the installed long groove(0A)(0B)(0C) which is seperated or united for. the oil circulation at the inside wall of crank-pin bearing which is attached to inside of slider(S).

8. Two stroke diesel engine having complex piston according to claim 1 or 4, which is composed to lubricate both of inside walls of cylinder(C)(C) and inside walls of air precompression room(22)(22') by the divided sending of oil at oil pathway

(5a)(5a') to the piston for combustion chamber(l)(l') and the piston for air precompression(3)(3') from center hallow of crank-shaft(CS) through the oil hole of crank-pin and crank-pin bearing(12)(12') and the oil pathway of the slider(S) and se i- circular type bearing(8)(8' ) .

9. Two stroke diesel engine having complex piston according to claim 6, which is installed semicircular type long groove(31) (31'), instead of abolition of the head part(H)(H') of engine body(E), and which is inducing the air swirl of the compulsory intake air from air tank(T), at the same time, forming com¬ bustion chamber(F)(F').