CN114483358A

CN114483358A - Thermodynamic single cylinder engine

Info

Publication number: CN114483358A
Application number: CN202111673359.1A
Authority: CN
Inventors: 张继杨; 王静秋; 姚聪; 蔡文新; 潘理杰
Original assignee: Dongfeng Motor Group Co Ltd
Current assignee: Dongfeng Motor Group Co Ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-05-13
Anticipated expiration: 2041-12-31
Also published as: CN114483358B

Abstract

The invention discloses a thermodynamic single cylinder engine, which solves the technical problems that the conventional single cylinder engine is high in test cost, is only suitable for development of a new engine type and cannot be suitable for technical upgrading of a mass-production engine type. The thermodynamic single cylinder engine provided by the invention is obtained by mass production based on the improvement of a machine type, and the cylinder body is suitable for mass production of the cylinder body of a multi-cylinder engine, and the structure of the cylinder body is not required to be improved. The cylinder head is formed by a cylinder head and a cover plate, wherein the cylinder head has all functional structures of the engine head. According to the test requirements, the cylinder cover can adopt a single-cylinder cover, a double-cylinder cover, a three-cylinder cover and the like. The cover plate is used for closing other cylinders of a cylinder body of the multi-cylinder engine. The thermodynamic single-cylinder machine formed by the method has the advantages of rapidness, low cost, easiness in adjustment and the like of the thermodynamic single-cylinder machine, and the optimal technical effects of cost, period, test effect and the like of the thermodynamic single-cylinder machine can be finally realized by utilizing the existing prototype boundary and test tooling of a mass-production multi-cylinder machine.

Description

Thermodynamic single cylinder engine

Technical Field

The application belongs to the technical field of engines, and particularly relates to a thermodynamic single cylinder engine.

Background

As national emission and fuel consumption regulations continue to tighten and in response to the rapid demands of the automotive market, the cycle of engine development and technology upgrade continues to be compressed. The performance development of the traditional engine is generally to make various combustion system optimization schemes, a large number of tests and comparisons are carried out on an engine test bed, and the final configuration scheme of the engine is determined according to test results. The method has high development cost and long period, and is often difficult to obtain an ideal optimal configuration scheme in the prediction stage of a new product scheme, and the reliability and the accuracy of the prediction scheme are low. The single-cylinder testing machine has the same structure and working principle as the multi-cylinder machine, and the single-cylinder machine has low manufacturing and testing cost and is easy to adjust; therefore, the single-cylinder engine development and research has very important significance for reducing the development cost of the engine, shortening the development period and carrying out high-performance product research.

The existing single cylinder engine is to trial-manufacture a whole set of special parts for the single cylinder engine according to the definition of the part technology, a special bench test tool needs to be prepared, and the subsequent test needs to be carried out on a special thermodynamic single cylinder engine bench. Therefore, the single-cylinder engine test in the prior art needs to invest in large parts, work trial-manufacturing cost and a special test bench, is only suitable for development of all new models, and cannot be suitable for technical upgrading of mass-production models.

Disclosure of Invention

In order to solve the technical problems, the invention provides a thermodynamic single cylinder machine, which can adopt a test bed of the existing mass production machine type, and reduce the research and development cost.

The technical scheme adopted for realizing the purpose of the invention is that the thermodynamic single cylinder engine comprises:

the cylinder body is provided with at least two cylinder barrels;

the cylinder cover is connected to the cylinder block and covers the first cylinder barrel of the cylinder block;

the cover plate is connected to the cylinder body and covers other cylinder barrels of the cylinder body;

the crankshaft system comprises a crankshaft, functional pistons, at least one balance piston and connecting rods, the number of the connecting rods is the same as that of the cylinder barrels, the crankshaft is rotatably installed in the cylinder block, the functional pistons are hinged to the crankshaft through the connection and movably arranged in the first cylinder barrel, the balance pistons are hinged to the crankshaft through the connection and movably arranged in the other cylinder barrels, and the balance pistons are provided with through vent holes.

Optionally, the cylinder cover and the cover plate are arranged side by side along the arrangement direction of the cylinder barrels, the butt ends of the cylinder cover and the cover plate are respectively provided with a first butt joint structure and a second butt joint structure which are matched with each other, the cylinder cover and the cover plate are positioned through the first butt joint structure and the second butt joint structure, and the cylinder cover and the cover plate are connected and fixed through a threaded fastener.

Optionally, the first butt joint structure and the second butt joint structure are both provided with pin holes, and positioning pins are inserted into the pin holes;

or, the first butt joint structure is provided with a positioning hole, the second butt joint structure is correspondingly provided with a positioning column, and the positioning column is inserted into the positioning hole.

Optionally, the first butt joint structure is a step structure, and the second butt joint structure is an inverted step structure; the step structure is in clearance fit with the butt joint surface of the inverted step structure; a chamfer is arranged at the edge and/or the surface layer of the step structure and the corner of the side surface; a chamfer is arranged at the edge and/or the folded angle between the surface layer and the side surface of the inverted ladder structure;

the positioning pin/positioning column is in clearance fit with the pin hole/positioning hole; the length of the positioning pin/positioning column is smaller than the total depth of the pin hole/positioning hole.

Optionally, the gap between the step structure and the surface layer of the inverted step structure is 0.2-0.4 mm; the side gap between the step structure and the inverted step structure is 0.2-0.5 mm; and an aluminum repairing agent is filled in a gap between the butt joint end of the cylinder cover and the butt joint end of the cover plate.

Optionally, a connecting side plate is arranged at the butt joint end of the cover plate, and the cylinder cover is fixedly connected with the connecting side plate through the threaded fastener; the end face of the connecting side plate protrudes out of the end face of the butt joint end of the cover plate;

the cover plate is provided with convex ridges extending along the arrangement direction of the cylinder barrels, and the connecting side plate is connected with the convex ridges; and more than 3 leveling threaded holes for mounting leveling bolts are formed in the end face, far away from the assembly sealing surface, of each raised ridge.

Optionally, a cylinder body lubricating oil path is arranged in the cylinder body; and a second inlet oil duct, a middle oil duct and a camshaft lubricating oil path which are sequentially communicated are arranged in the cylinder cover, and the second inlet oil duct is communicated with the cylinder body lubricating oil path.

Optionally, the second inlet oil passage has a horizontal direction projection component and a vertical direction projection component; the included angle between the axis of the second inlet oil duct and the vertical direction is 30-60 degrees;

the outer end of the second inlet oil passage is positioned on the bottom surface of the cylinder cover, and a transfer hole is formed in the outer end of the second inlet oil passage; the switching hole is a waist-shaped hole; the depth of the transfer hole is 5 mm-8 mm.

Optionally, a camshaft and a camshaft support for mounting the camshaft are arranged on the top of the cylinder head, and the camshaft lubricating oil path is arranged in the camshaft support and the camshaft; the camshaft lubrication oil passage includes:

the air inlet and exhaust side through oil passage is intersected with the middle oil passage structure;

the circulating oil path of the intake variable valve timing system, the hollow oil path of the intake camshaft and the oil supply inclined hole of the intake cam shaft neck are communicated in sequence;

the exhaust variable valve timing system comprises an exhaust variable valve timing system circulating oil path, an exhaust camshaft hollow oil path and an exhaust cam shaft neck oil supply inclined hole which are communicated in sequence;

wherein the intake variable valve timing system circulation oil passage and the exhaust variable valve timing system circulation oil passage are communicated through the intake and exhaust side through oil passage.

Optionally, a cylinder water jacket is arranged in the cylinder block; the cylinder cover is internally provided with a water inlet, a water outlet and a water jacket cavity which are communicated, and the water inlet and the water outlet are positioned at the bottom of the cylinder cover and are respectively communicated with the water jacket cavity and the cylinder body water jacket.

Optionally, a combustion chamber top cover is arranged in the cylinder head, and the water jacket chamber is arranged around the periphery of the combustion chamber top cover; the water inlet is close to the exhaust side of the cylinder head; the water outlet is close to the air inlet side of the cylinder cover;

the number of the water inlets and the water outlets is more than one; the water inlet and the water outlet are arc-shaped strip-shaped holes; the inner diameters of the water inlet and the water outlet are different.

Optionally, an inward-recessed flow guide groove is formed in the top surface of the balance piston, and the vent hole is communicated with the flow guide groove; the flow guide groove is a conical groove, the flow guide groove extends from the center of the top surface of the balance piston to the edge, and the vent hole is located at the tip end of the conical groove.

Optionally, the diameter of the outer circle of the balance piston is the same as that of the functional piston; the balance piston and the functional piston have equal mass.

Optionally, the thermodynamic single cylinder engine further includes:

and cylinder gaskets arranged between the cylinder block and the cylinder head and between the cylinder block and the cover plate to seal assembly sealing surfaces of the cylinder block, the cylinder head and the cover plate.

Optionally, the cylinder head is provided with an oil injector, a spark plug and a cylinder pressure sensor, the oil injector, the spark plug and the cylinder pressure sensor all extend into the combustion chamber, and the oil injector and the spark plug are arranged at an angle;

a concave pit is formed in the center of the top surface of the functional piston, and the axes of the fuel injector, the spark plug and the functional piston penetrate through the concave pit; and the oil injection port of the oil injector is close to the edge of the concave pit.

According to the technical scheme, the thermodynamic single cylinder engine is obtained by improving based on a mass production machine type, the cylinder body of a multi-cylinder engine is continuously produced in mass production, and the structure of the cylinder body does not need to be improved. The cylinder head is formed by a cylinder head and a cover plate, wherein the cylinder head has all functional structures of the engine head. According to the test requirements, the cylinder cover can adopt a single-cylinder cover, a double-cylinder cover, a three-cylinder cover and the like. The cover plate is used for closing other cylinders of a cylinder body of the multi-cylinder engine. The thermodynamic single-cylinder machine formed by the method has the advantages of rapidness, low cost, easiness in adjustment and the like of the thermodynamic single-cylinder machine, and the optimal technical effects of cost, period, test effect and the like of the thermodynamic single-cylinder machine can be finally realized by utilizing the existing prototype boundary and test tooling of a mass-production multi-cylinder machine.

Drawings

Fig. 1 is a schematic structural diagram of a thermodynamic single cylinder engine in an embodiment of the invention.

Fig. 2 is an assembly structure view of a cylinder block and a cylinder head in the thermodynamic single cylinder engine of fig. 1.

FIG. 3 is a schematic diagram of the structure of the cylinder head assembly of the thermodynamic single cylinder engine of FIG. 1.

Fig. 4 is a schematic structural view of a cylinder head in the cylinder head assembly of fig. 3.

Fig. 5 is a cross-sectional view of a first docking structure in the cylinder head of fig. 4.

Fig. 6 is a schematic structural view of a cover plate in the cylinder head assembly of fig. 3.

Fig. 7 is a cross-sectional view of a second mating structure in the cover plate of fig. 6.

Fig. 8 is a cross-sectional view of the cylinder head assembly of fig. 3 with the first and second mating structures in an assembled state.

Fig. 9 is a schematic structural view of a leveling process of the cylinder head assembly of fig. 3.

Fig. 10 is a front view of fig. 9.

Fig. 11 is a cross-sectional view of an oil passage of a cylinder head in the cylinder head assembly of fig. 3.

Fig. 12 is a diagram showing an oil passage structure of a lubricating system of a cylinder head in the cylinder head assembly of fig. 3.

Fig. 13 is a schematic view of the bottom surface of the cylinder head in the cylinder head assembly of fig. 3.

Fig. 14 is a schematic structural view of a water jacket in the cylinder head of fig. 13.

Fig. 15 is a schematic structural view of the water jacket of fig. 14 from another perspective.

Fig. 16 is a schematic structural diagram of a crankshaft system in the thermodynamic single cylinder engine of fig. 1.

FIG. 17 is a schematic diagram of a functional piston in the crankshaft system of FIG. 16.

Fig. 18 is an assembled structural view of a functional piston, an injector and a spark plug in the thermodynamic single cylinder engine of fig. 1.

Description of reference numerals:

1000-thermodynamic single cylinder engine; 1100-cylinder head.

100-cylinder cover, 101-assembly sealing surface of the cylinder cover, 110-step structure, 111-upper edge of the step structure, 112-bevel of surface layer and side surface, 113-lower edge of the step structure; 120-a first inlet gallery; 130-intermediate oil ducts; 140-a second inlet gallery; 150-camshaft lubricating oil path, 151-intake and exhaust side through oil path, 152-intake variable valve timing system circulating oil path, 153-intake camshaft hollow oil path, 154-intake cam shaft neck oil supply inclined hole, 155-exhaust variable valve timing system circulating oil path, 156-exhaust camshaft hollow oil path, 157-exhaust cam shaft neck oil supply inclined hole; 160-oil return hole; 171-plug; 181-water inlet, 182-water outlet; 190-combustion chamber top cover.

200-cover plate, 201-assembly sealing surface of cover plate, 210-connecting side plate, 211-fixing threaded hole, 220-raised ridge, 221-leveling threaded hole, 222-threaded hole, 230-inverted ladder structure, 231-pin hole, 232-upper edge of inverted ladder structure, 233-lower edge of inverted ladder structure.

300-a cylinder block; 310-cylinder lubricating oil path; 320-a cylinder barrel; 400-a generator; 500-air conditioning compressor; 600-a cooling system; 700-lubrication system.

1-a stud; 2-a nut; 3-positioning pins; 4-aluminum healant; 5-storing the glue and chamfering; 6-clearance; 7-leveling bolts; 14-a transfer hole; 15-cylinder cover water jacket.

20-crankshaft system, 21-crankshaft, 22-functional piston, 221-pit, 23-connecting rod, 24-balance piston, 25-vent hole, 26-diversion groove.

30-a fuel injector; 40-a spark plug; 50-cylinder pressure sensor; 60-combustion chamber.

Detailed Description

In order to make the present application more clearly understood by those skilled in the art to which the present application pertains, the following detailed description of the present application is made with reference to the accompanying drawings by way of specific embodiments.

In the related technology, a whole set of special parts for the single cylinder engine are trial-manufactured according to the definition of the part technology, a special bench test tool needs to be prepared, and the subsequent test needs to be carried out on a special thermodynamic single cylinder engine bench. For the technical upgrading of mass-produced models, the improvement of local systems such as a combustion system and the like is mainly related, other structures and systems continue to use the original models, and if the single-cylinder engine is input, parts and boundaries of the original models cannot be greatly utilized, so that the problems of high part test cost and long test preparation period exist. And the difference of the single-cylinder engine and the multi-cylinder engine on cooling and lubricating systems causes certain difference of test precision. Therefore, the technology upgrading of the existing mass production model is lack of test tools and difficult to upgrade.

In order to solve the problems of the related art, the embodiment of the application provides the thermodynamic single-cylinder machine, parts, boundaries and a test bed of the existing mass production machine type can be adopted, and the thermodynamic single-cylinder machine not only serves as a single-cylinder testing machine, but also can be used for technical upgrading of mass production machine types.

The technical scheme of the application is defined in detail by combining the following specific embodiments:

the present embodiment provides a single thermodynamic cylinder machine 1000, and referring to fig. 1 and fig. 2, the single thermodynamic cylinder machine 1000 includes a cylinder block 300, a cylinder head assembly 1100 and a crankshaft system 20, in order to ensure the sealing performance of the cylinder block 300 and the cylinder head assembly 1100, a cylinder gasket is generally disposed between the cylinder block 300 and the cylinder head assembly 1100, and the cylinder gasket seals the assembly sealing surface of the cylinder block 300 and the cylinder head assembly 1100. Crankshaft system 20 is mounted to cylinder block 300 and operates within cylinder block 300 in a conventional manner as disclosed in the prior art, and the details of which are not described herein. The thermodynamic single cylinder engine 1000 is an improvement of a mass production multi-cylinder engine, i.e., the cylinder head assembly 1100 can be adapted to a cylinder block of a two-cylinder engine, a cylinder block of a three-cylinder engine, a cylinder block of a four-cylinder engine, or a multi-cylinder engine of other cylinder numbers.

Referring to fig. 1, the thermodynamic single cylinder engine 1000 further includes necessary accessories such as a generator 400, an air conditioner compressor 500, a cooling system 600, a lubricating system 700, and the like, wherein the cooling system 600 mainly includes a water pump, a radiator, and the like, and is used for realizing circulation of coolant in the engine and cooling the cylinder block 300 and the cylinder head assembly 1100. The lubricating system 700 mainly includes an oil pump, an oil cooler, an oil filter, and the like, and is used to realize circulation of oil in the engine and lubricate each kinematic pair of the engine. The accessories are conventional configurations of engine systems, and the present embodiment is not modified, and details thereof are disclosed in the related art and will not be described herein.

In the present embodiment, a mass production four-cylinder engine is modified into a thermodynamic single cylinder engine 1000 by way of example, the cylinder block 300 is a mass production four-cylinder engine cylinder block 300, that is, four cylinders are disposed in the cylinder block 300, and the four cylinders are sequentially arranged along a set direction, the structure of the cylinder block 300 in the present embodiment is not modified, and specific contents may refer to related disclosures in the prior art and will not be described herein. The cylinder head assembly 1100 includes two parts, i.e., a single cylinder head 100 and a cover plate 200, the single cylinder head 100 covers a first cylinder (first cylinder for short) of the four-cylinder block 300, and the cover plate 200 covers other cylinders, i.e., a second cylinder, a third cylinder, and a fourth cylinder, of the four-cylinder block 300.

Referring to fig. 2 and 3, the cylinder head assembly 1100 mainly includes two parts, namely a cylinder head 100 and a cover plate 200, the cylinder head 100 and the cover plate 200 are arranged side by side along the arrangement direction of the cylinders of the cylinder block and are respectively used for covering different cylinders of the cylinder block, and the cylinder head 100 and the cover plate 200 are respectively provided with a cylinder head bolt through hole for connecting and fixing with the cylinder block through bolts.

In order to meet the assembly sealing requirement of the cylinder head assembly 1100, a first butt joint structure and a second butt joint structure which are matched with each other are respectively arranged at the butt joint end of the cylinder head 100 and the butt joint end of the cover plate 200, the cylinder head 100 and the cover plate 200 are positioned through the first butt joint structure and the second butt joint structure, and the first butt joint structure and the second butt joint structure are used for realizing the assembly positioning of the cylinder head 100 and the cover plate 200. The cylinder head 100 and the cover plate 200 are fastened and fixed by a screw fastener, and the screw fastener for fastening and fixing may be provided in the butt structure or in another position of the cylinder head 100 and the cover plate 200. First butt joint structure and second butt joint structure can adopt location structure such as tooth meshing, mortise and tenon joint, step location, and specific structural style this application does not do the restriction.

According to the novel engine system, the cylinder head and the cylinder block of the mass-production multi-cylinder engine are assembled by using the mass-production cylinder gasket, and the structure of the cylinder head is different from that of the cylinder head of the mass-production multi-cylinder engine, so that the problems that the fastening connection and the sealing between the cylinder head and the multi-cylinder block become the reliability of the novel engine system, and if the cylinder gasket is sealed and fails, the cooling liquid in the water jacket of the cylinder block leaks to the oil pan to cause oil-water mixing are solved. In the cylinder head assembly 1000 of the embodiment, the abutting ends of the cylinder head 100 and the cover plate 200 are respectively provided with a first abutting structure and a second abutting structure which are matched with each other, the cylinder head 100 and the cover plate 200 are positioned through the first abutting structure and the second abutting structure, the cylinder head 100 and the cover plate 200 are connected and fixed through the threaded fasteners, and the cylinder head 100 and the cover plate 200 form a united body through the positioning and the fixed connection of the cylinder head 100 and the cover plate 200, and the assembly sealing surface meets the flatness requirement and can be well sealed with the cylinder block.

Referring to fig. 4 to 8 in particular, in the present embodiment, the first docking structure and the second docking structure employ a pin positioning structure. Specifically, the pin holes 231 can be formed in the first butt joint structure and the second butt joint structure, and the positioning pins 3 are inserted into the two communicated pin holes 231, so that positioning is achieved. In other embodiments, a positioning hole may be disposed on the first docking structure or the second docking structure, a positioning post is correspondingly disposed on the second docking structure or the first docking structure, and the positioning post is inserted into the positioning hole during assembly, so as to achieve positioning.

In order to simplify the structure, the first butt joint structure and the second butt joint structure adopt a step positioning structure. Referring to fig. 5 and 7, the first docking structure is a step structure 110, the second docking structure is an inverted step structure 230, that is, the second docking structure is an inverted step structure, the step height of the step structure 110 is 10mm ± 1mm, and the step width is 9.5mm ± 0.5 mm. In this embodiment, the step structure 110 and the inverted step structure 230 are both provided with pin holes 231, and the number of the pin holes 231 is 2-4.

In order to ensure good working condition of the engine, the cylinder body and the cylinder cover need to be ensured to have excellent sealing performance. In order to improve the sealing performance, in this embodiment, the step structure 110 is in clearance fit with the abutting surface (including the step surface layer and the step side surface) of the inverted step structure 230, and the gap 6 is sealed by a filler. Specifically, the surface layer gap between the step structure 110 and the inverted step structure 230 is 0.2-0.4 mm; the side gap 6 between the step structure 110 and the inverted step structure 230 is 0.2-0.5 mm, and the gap 6 can ensure smooth filling of fillers and avoid the reduction of the connection strength between the cylinder cover 100 and the cover plate 200 caused by the overlarge gap. By adding the filler into the gap 6, the good sealing of the joint surface of the first joint structure and the second joint structure can be realized, the filler can be a material commonly used in the sealing field, and the aluminum repairing agent 4 is adopted in the embodiment.

Since there is a flow resistance at the edges and corners of the steps, in order to facilitate the filling operation of the filler and store the filler as much as possible, in this embodiment, a chamfer is provided at the edges and/or corners of the surface layer and the side surface of the stepped structure 110, and a chamfer is provided at the edges and/or corners of the surface layer and the side surface of the inverted stepped structure 230. The chamfer can be an oblique angle chamfer or a circular arc chamfer, and the application is not limited. Specifically, in this embodiment, a 1mm × 45 ° chamfer is provided at the upper edge 111 of the stepped structure 110 and the corner 112 between the surface layer and the side surface, and a 1.5mm × 30 ° chamfer is provided at the lower edge 113 (close to the assembly sealing surface) of the stepped structure 110; the upper edge 232 of the inverted step structure 230 is provided with a 1.25mm x 45 ° chamfer, and the lower edge 233 (near the assembly sealing surface) is provided with a 1.5mm x 30 ° chamfer.

To further improve the sealing performance, in some embodiments, the length of the positioning pin 3/positioning post may be set to be smaller than the total depth of the pin hole 231/positioning hole, so that at least one end of the positioning pin 3/positioning post is embedded in the pin hole 231/positioning hole, and the gap between the pin shaft and the hole can be sealed by the filler.

In order to ensure the structural strength of the first and second docking structures, in this embodiment, the cylinder head 100 and the cover plate 200 are connected and fixed by a threaded fastener, and the threaded fastener for connecting and fixing the cylinder head 100 and the cover plate 200 is disposed at other positions of the cylinder head 100 and the cover plate 200. Referring to fig. 3, 4 and 6 in particular, the butt end of the cover plate 200 is provided with a connection side plate 210, and the cylinder head 100 is fixedly connected to the connection side plate 210 by a threaded fastener, which may be a screw, a bolt, a stud bolt or other fasteners. In order to further improve the sealing effect, the end face of the connecting side plate 210 protrudes from the end face of the butt end of the cover plate 200, that is, the end face of the connecting side plate 210 close to the cylinder head 100 protrudes from the step side face of the outermost end of the cover plate 200, so that a stable gap is maintained between the step side face of the outermost end of the cover plate 200 and the step side face of the corresponding position of the cylinder head 100, and fillers are contained.

In order to improve the structural strength of the connecting side plate 210, the upper surface of the cover plate 200 is provided with a convex ridge 220 extending along the arrangement direction of the cylinder barrels, the connecting side plate 210 is connected to the end of the convex ridge 220, the convex ridge 220 strengthens the connecting side plate 210 on one hand, on the other hand, the convex ridge 220 can also be used as the installation foundation of external structural members, for example, more than 3 leveling bolts 7 are arranged on the end surface of the convex ridge 220 away from the assembly sealing surface, and the leveling bolts 7 can level the cylinder head 100 and the cover plate 200 during assembly, thereby ensuring the flatness of the assembly sealing surface of the cylinder head assembly 1100. The end face of the ridge 220 remote from the mating sealing surface is provided with a threaded hole 222 for mounting other accessories of the engine.

Referring to fig. 6, in the present embodiment, two convex ridges 220 are disposed on the upper surface of the cover plate 200, and the two convex ridges 220 extend along the arrangement direction of the cylinder and are symmetrically distributed. Two ridges 220 are respectively provided with 2 leveling threaded holes 221, the 2 leveling threaded holes 221 have a larger distance, the distance is larger than 100mm, for example 115mm, and the larger distance ensures the flatness of the cover plate 200 and the bottom surface of the cylinder cover 100 in the leveling process. The two ridges 220 are also provided with 3 threaded holes 222 for mounting other accessories of the engine.

Since the cylinder head assembly 1100 is assembled by the cylinder head 100 and the cover plate 200 in this embodiment, it is necessary to ensure that the assembly sealing surface of the cylinder head 100 and the cover plate 200 has good flatness, and the cylinder head assembly 1100 of this embodiment is assembled by specifically adopting the following assembly method. Referring to fig. 9 and 10, the assembly method specifically includes the steps of:

s1: the cylinder head 100 and the cover plate 200 are fixed with the cylinder block 300 to pre-position the cylinder head 100 and the cover plate 200.

Taking the single cylinder head 100 as an example, the single cylinder head 100 and the cover plate 200 are respectively assembled to the cylinder block 300, the single cylinder head 100 is mounted to the first cylinder at the front end of the cylinder block 300, and the cover plate 200 is mounted behind the cylinder head 100. Specifically, because the butt ends of the cylinder cover 100 and the cover plate 200 are respectively provided with the step structure 110 and the inverted step structure 230, the step structure 110 and the inverted step structure 230 are matched during assembly, the cylinder cover bolt through holes in the cylinder cover 100 and the cover plate 200 are matched with the axis of the cylinder cover bolt hole in the cylinder block 300, 10 cylinder cover 100 bolts respectively penetrate through the cylinder cover bolt through holes in the cylinder cover 100 and the cover plate 200, the cylinder cover 100 bolts are screwed in a cross screwing sequence from inside to outside, and the pre-positioning of the single-cylinder cover 100 and the cover plate 200 is realized by screwing the cylinder cover 100 bolts.

S2: according to the pin hole 231 of the cover plate 200, the circle center position of the pin hole 231 of the cylinder cover 100 is determined, the circle center point is marked, the pin hole 231 of the cylinder cover 100 is machined according to the circle center point, and the deviation between the center line of the pin hole 231 of the cylinder cover 100 and the center line of the pin hole 231 of the cover plate 200 is ensured to be less than 0.10 mm.

Specifically, two pin holes 231 are machined in advance in the inverted stepped structure 230 of the cover plate 200, the position of the center of a circle of the pin holes 231 on the stepped structure 110 of the cylinder head 100 is determined by means of horizontal and vertical scribing lines by using the relative positions of the two pin holes 231 on the step of the cover plate 200, and a central punch is used for punching a central point at the intersection of the horizontal and vertical scribing lines, wherein the central point is the center of the circle.

Drilling according to the determined center point

The small hole of the measuring device detects the gross error offset from the center of the bottom hole to the reference surface by using a caliper, the positions of the bottom hole and the ideal center are calculated by actual measurement,if the excessive loss is not more than 0.10mm, the drill bit can be compensated by properly increasing the top angle of the drill bit and weakening the automatic centering function during reaming and properly pushing the workpiece in the positive direction to gradually increase the diameter of the drill bit. If the excessive loss is larger than 0.10mm, the two side walls of the bottom hole can be trimmed by using a mixed round file, the trimmed parts are in smooth transition connection with the circular arc of the bottom hole, and finally the deviation of the center lines of the pin holes 231 on the cylinder cover 100 and the cover plate 200 is ensured to be smaller than 0.10 mm. The punching and drilling operations must adopt a vertical drill orientation, i.e. the tool is ensured to be vertically downward and perpendicular to the upper surface of the cylinder cover.

S3: according to the fixing threaded hole 211 on the connecting side plate 210 of the cover plate 200, the circle center position of the threaded hole of the cylinder cover 100 is determined and the circle center point is marked, the threaded hole of the cylinder cover 100 is processed according to the circle center point, and the deviation between the threaded hole of the cylinder cover 100 and the center line of the fixing threaded hole 211 of the cover plate 200 is ensured to be less than 0.10 mm.

Specifically, two fixing threaded holes 211 are processed in advance on the two connecting side plates 210 of the cover plate 200, the circle center position of the threaded hole of the cylinder head 100 is determined by the same method as that in step S2, the circle center point is marked, the threaded hole is formed by drilling, reaming, tapping and other processes, and the deviation between the axis of the threaded hole and the axis of the fixing threaded hole 211 on the connecting side plate 210 of the cover plate 200 is required to be less than 0.10 mm.

S4: the positioning pins 3 are inserted into the pin holes 231 of the cylinder head 100 and the pin holes 231 of the cover plate 200, and threaded fasteners are screwed into the threaded holes of the cylinder head 100 and the threaded holes of the cover plate 200 to form a united body of the cylinder head 100 and the cover plate 200, and the united body is removed from the cylinder block 300.

Specifically, S41: a positioning pin 3 is inserted into a positioning pin 3 hole 231 of the cover plate 200 fixed to the cylinder block 300 and corresponding to the cylinder head 100; in the embodiment, a threaded fastener is screwed into a fixing threaded hole 211 of a connecting side plate 210 of the cover plate 200 and a threaded hole corresponding to the cylinder head 100, the threaded fastener adopts a flat-end asymmetric stud 1 with the thread specification of M6 multiplied by 1, the short end of the stud 1 is screwed into the threaded hole, then a nut 2 is screwed into the long end of the stud 1 and pre-tightened, the pre-tightening torque is 10 +/-1 N.m, and the cylinder head 100 and the cover plate 200 are fixedly connected through the stud 1 and the nut 2 to form a combined body. By adopting the combined fastening mode of the stud 1 and the nut 2, the stud 1 can be used for prepositioning between the cylinder cover and the cover plate 200 before pre-tightening, and frequent disassembly is convenient when each combined surface is leveled subsequently.

S42: bolts of the cylinder head 100 are disassembled from the outside to the inside in a crossing manner, and the cylinder head 100 and the head plate 200 are combined together from the cylinder block 300.

S5: leveling bolts 7 are mounted on the head plate 200, the assembly is placed on a plane with the assembly sealing surface facing upward, and the screwing amount of each leveling bolt 7 and/or threaded fastener is adjusted with the assembly sealing surface 101 of the cylinder head 100 as a horizontal reference, so that the horizontal inclination amount of the assembly sealing surface 201 of the head plate 200 is less than 0.04 mm.

Specifically, the leveling bolt 7 is screwed into the top leveling screw hole 221 of the cover plate 200, and the top surface of the cylinder head 100 is pressed downward against the inspection tool table surface a, as shown in fig. 9 and 10. And adjusting the screwing amount of each leveling bolt 7, measuring the integral flatness of the assembly sealing surface 201 of the cover plate 200 and the assembly sealing surface 101 of the cylinder cover 100 by using a level gauge, and when the inclination amount of the level gauge is less than 0.04mm, determining that the cover plate 200 and the bottom surface of the cylinder cover are horizontal. If the diameter is more than 0.04mm, the requirement of leveling the bottom surfaces of the cover plate 200 and the single-cylinder cover 100 is met by adjusting the stud bolts 1 of the cover plate 200 and the cylinder cover 100, so that the subsequent sealing of a cylinder gasket is facilitated.

S6: the gap 6 between the abutting end of the cylinder head 100 and the abutting end of the cover plate 200 is filled with the aluminum repair filler 4, and the cylinder head 100 and the cover plate 200 are bonded and fixed after the aluminum repair filler 4 is cured, thereby forming a cylinder head assembly 1100.

Specifically, the combined body posture in the step S5 is maintained, that is, the bottom surfaces of the cover plate 200 and the single-cylinder head 100 face upward, the aluminum repairing agent 4 is uniformly coated on the glue storage chamfer 5 formed by the step edge chamfer at the joint of the cover plate 200 and the bottom surface of the cylinder head 100 along the air intake and exhaust direction, the aluminum repairing agent 4 is in a liquid state and can be diffused along with the step gap 6 at the joint of the cover plate 200 and the single-cylinder head 100, and the gap between the cover plate 200 and the cylinder head 100 is ensured to be filled with the aluminum repairing agent 4.

And (3) smoothing the aluminum repairing agent 4 at the bottom surface glue storage chamfer 5 by using a scraper, standing the sample for 60 minutes, polishing the bottom surface glue storage chamfer 5 by using fine sand paper after the aluminum repairing agent 4 is completely cured, and checking the unevenness between the local part of the glue storage chamfer 5 and the bottom surface by using a knife edge ruler to ensure that the small unevenness is less than 0.02 mm. After the aluminum repairing agent 4 is completely cured, the bonding capability is strong, and the assembly gap reserved between the cover plate 200 and the cylinder cover 100 due to the machining precision is filled. The aluminum repairing agent 4 and the stud 1 are jointly connected with the cover plate 200 and the cylinder cover 100, so that the cover plate 200 and the cylinder cover 100 are fixedly connected into a whole, the structural strength is good, and the assembly sealing surface of the united body has high flatness. After the bottom surface finishing step, the water pressure and the oil pressure on the cylinder gasket can be guaranteed to be blocked in an assembly state, and the sealing of the cylinder gasket is guaranteed.

According to the air intake and exhaust directions of the cylinder head and the axial direction of the engine crankshaft/camshaft, six directions of the cylinder head can be respectively defined as: front end a, rear end b, intake side c, exhaust side d, bottom surface and top surface. Wherein: front and rear ends refer to opposite sides of the cylinder head in the crankshaft/camshaft axial direction, the "front end" specifically refers to the side near the first cylinder, and the "rear end" specifically refers to the side near the last cylinder; the air inlet side and the air outlet side refer to two opposite sides close to an air inlet valve and an air outlet valve, the air inlet side specifically refers to one side close to an air inlet valve, and the air outlet side specifically refers to one side close to an air outlet valve; the top surface and the bottom surface refer to two opposite sides of the cylinder head in the piston moving direction (vertical engine, piston moving direction is generally vertical direction), the bottom surface is the side close to the cylinder block, the flatness of the side is high, so that the engine has good sealing performance, the top surface is the opposite side of the bottom surface, such as the cylinder head structure of the camshaft mounted on the cylinder head, and the top surface is the side close to the camshaft of the cylinder head. The "front end", "rear end", "intake side", "exhaust side", "top surface", and "bottom surface" in the present embodiment may all refer to the explanations mentioned above.

The cylinder head 100 is a box-shaped part with a complicated structure, and is formed with an intake valve seat hole, an exhaust valve seat hole, a valve guide hole, a mounting hole for mounting the ignition plug 40, and a mounting hole for mounting the fuel injector 30, and the cylinder head 100 is cast with a cooling water jacket, an intake and exhaust passage, and a combustion chamber therein, and if a camshaft is mounted on the cylinder head 100, a camshaft mounting seat and a lubricating oil passage are formed in the cylinder head 100. Referring specifically to fig. 11 and 12, in the present embodiment, the cylinder head 100 is provided therein with the second inlet oil passage 140 and the intermediate oil passage 130 communicating with each other. A block lubrication oil passage 310 is provided in the single cylinder block, and the second inlet oil passage 140 communicates with the block lubrication oil passage 310.

The opening of the second inlet oil passage 140 is located on the bottom surface of the cylinder head 100, and in order to facilitate the communication between the cylinder head 100 and the cylinder block lubrication system, a transfer hole 14 is provided in the opening of the second inlet oil passage 140, the transfer hole 14 may be directly cast or machined, the cross-sectional area of the transfer hole 14 should be larger than the cross-sectional area of the second inlet oil passage 140, and the transfer hole 14 completely covers the second inlet oil passage 140.

The position of the transfer hole 14 needs to be opposite to the position of the oil hole on the upper surface of the cylinder block, and therefore the position of the transfer hole 14 is generally spaced from the axial direction of the intermediate oil passage 130, so that the second inlet oil passage 140 is in an inclined structure. The specific second inlet oil passage 140 has a horizontal direction projected component and a vertical direction projected component, that is, the second inlet oil passage 140 is inclined with respect to both the horizontal direction and the vertical direction. Wherein, the included angle between the axis of the second inlet oil passage 140 and the vertical direction is 30 ° to 60 °, for example, 35 °, 41 °, 45 °, 48 °, 53 °, 57 °, and the like.

In order to facilitate the oil path butt joint, referring to fig. 12, in this embodiment, the adapting hole 14 is a kidney-shaped hole, and the shape of the kidney-shaped hole enables the assembly seal of the cylinder cover and the cylinder body to have a certain fault-tolerant capability, so that the difficulty in arranging the oil path can be reduced. The depth of the through hole 14 is 5mm to 8mm, for example, 5.2mm, 5.7mm, 6.5mm, 7.5mm, etc. The waist-shaped transfer hole 14 has a certain volume, so that the pressure fluctuation of engine oil at the cylinder cover part can be reduced, and a certain buffer effect is realized on the pressure of an oil channel at the cylinder cover part.

In order to facilitate oil drainage, in the embodiment, the rear end of the cylinder head 100 is provided with an oil return hole 160 communicated with an oil cavity inside the cylinder head 100, and a pipe joint is installed in the oil return hole 160 and communicated with a test bench lubricating system to ensure the circulation of engine oil.

A camshaft lubrication oil passage 150 is provided in the camshaft support, and referring to fig. 12, the camshaft lubrication oil passage 150 intersects the intermediate oil passage structure 12, so that the intermediate oil passage 130 communicates with the camshaft lubrication oil passage 150 after the intermediate oil passage structure 12 is machined into the intermediate oil passage 130. The camshaft lubricating oil path 150 includes an intake side lubricating oil path, an exhaust side lubricating oil path, and an intake and exhaust side through oil passage 151, and the intake side lubricating oil path and the exhaust side lubricating oil path are communicated through the intake and exhaust side through oil passage 151, and are integrally of a symmetrical structure, thereby ensuring that the intake and exhaust side lubricating oil pressures are the same. The intake and exhaust side through oil passage 151 intersects with the intermediate oil passage structure 12, so that after the intermediate oil passage structure 12 is machined into the intermediate oil passage 130, the intermediate oil passage 130 communicates with the camshaft lubricating oil passage 150.

Specifically, the intake side lubricating oil path includes an intake variable valve timing system circulation oil path 152, an intake camshaft hollow oil path 153, and an intake cam journal oil supply inclined hole 154, which are sequentially communicated. The exhaust side lubrication oil passage includes an exhaust variable valve timing system circulation oil passage 155, an exhaust camshaft hollow oil passage 156, and an exhaust cam journal oil supply inclined hole 157, which are sequentially communicated. The intake variable valve timing system oil circulation passage 152 and the exhaust variable valve timing system oil circulation passage 155 are communicated with each other via the intake and exhaust side oil through passage 151. The intake variable valve timing system circulation oil passage 152 and the exhaust variable valve timing system circulation oil passage 155 communicate with the intake side cam journal oil groove and the exhaust side cam journal oil groove, respectively.

After being pressurized by the oil pump, engine oil firstly passes through the main oil gallery of the cylinder body to lubricate the main bearing neck of the crankshaft and provide oil pressure for the timing chain tensioner, a tensioning guide plate is ensured to be always attached to a timing chain, a piston is cooled through a piston cooling nozzle, and the rest part of the engine oil passes through the waist-shaped switching hole 14 in the bottom surface of the cylinder cover and enters the main oil gallery of the cylinder cover 100. Referring to fig. 12, an intake-exhaust side through oil passage 151 is disposed at the bottom of the camshaft support, the oil passage is communicated with an oil groove of a cam journal, and is used for lubricating the cam journal and supplying oil to a VVT system (variable valve timing system) to ensure accurate control of a valve timing of the VVT system, and after lubricating the cam journal, lubricating fluid enters an oil passage inside the camshaft, namely an intake camshaft hollow oil passage 153/an exhaust camshaft hollow oil passage 156, lubricates other cam journals, is finally discharged from an intake cam journal oil supply inclined hole 154/an exhaust cam journal oil supply inclined hole 157, is discharged to a cylinder head oil chamber through a cam journal gap, is discharged through an oil return hole 160 disposed at the rear end of the cylinder head 100, and flows back to a rack lubrication system, thereby realizing circulation of lubricating fluid (e.g., engine oil).

Referring to fig. 13 to 15, a water inlet 181, a water outlet 182 and a water jacket chamber are provided in the cylinder head 100 in communication; the water inlet 181 and the water outlet 182 are both machined, and the water inlet 181 and the water outlet 182 are specifically located at the bottom of the cylinder head 100 and respectively communicate the water jacket chamber with the cylinder water jacket.

The novel thermodynamic single cylinder engine 1000 composed of a single cylinder cover and a mass-produced cylinder block is an integral cooling system, namely, after being pressurized by an engine water pump, coolant firstly passes through the air inlet side of a cylinder block water jacket, is guided to the air outlet side of the cylinder block water jacket through a coolant partition plate, and enters the air outlet side of the cylinder block 100 water jacket 15 through a water inlet 181 on the bottom surface of the cylinder cover. Referring to fig. 14 and 15, under the pressure of the cooling system, the coolant passes through the air inlet side of the water jacket 15 of the cylinder head 100 and enters the water jacket on the air inlet side of the cylinder block through the water outlet 182 on the bottom surface of the air inlet side of the cylinder head 100, then is discharged to the engine body, is guided to the radiator through the cooling pipeline and finally returns to the water pump, and the circulation of the coolant in the engine system is realized.

In this embodiment, a water inlet 181 is required to be disposed on the exhaust side and a water outlet 182 is required to be disposed on the intake side in the region where the cylinder head bottom surface and the cylinder body top surface water jacket are combined. In the specific embodiment, a groove is formed in a region where the cylinder head bottom surface and the cylinder head top surface water jacket are combined and communicated with the cylinder head water jacket 15, the number of the water inlets 181 and the water outlets 182 is not limited to one, and for example, a plurality of water inlets 181 and a plurality of water outlets 182 may be formed at intervals in the circumferential direction. The shapes of the water inlet 181 and the water outlet 182 are not limited to holes or grooves, and are determined according to the shape of the water jacket of the cylinder. Referring to fig. 14, in this embodiment, the water inlet 181 and the water outlet 182 are both arc-shaped strip-shaped holes, and the inner diameters of the water inlet 181 and the water outlet 182 are different.

Referring specifically to fig. 16 and 18, in the present embodiment, the crankshaft system 20 includes a crankshaft 21, a functional piston 22, at least one balance piston 24, and connecting rods 23 with the same number as that of the cylinder barrels, a plurality of connecting rods necks are disposed on the crankshaft 21 at intervals, the plurality of connecting rods 23 are respectively hinged to the connecting rods necks, the functional piston 22 is disposed in the cylinder barrel 320 covered by the cylinder head 100 and is hinged to one of the connecting rods 23, and the functional piston 22 is used for driving the crankshaft 21 to rotate; each balance piston 24 is disposed in the other cylinder, and is hinged to the other connecting rods 23, and when the crankshaft 21 rotates, the balance pistons 24 are driven by the connecting rods 23 to ascend and descend along the inner wall of the cylinder 320.

Specifically, the crankshaft system 20 is provided with a crankshaft 21, a connecting rod 23 and a functional piston 22, wherein the functional piston 22 is hinged with the connecting rod 23; in the engine thermo-mechanical test, the functional piston 22 is disposed in the cylinder 320 of the cylinder block 300, the cylinder head assembly 40 is disposed on the top of the cylinder block, and the combustion chamber 60 is formed between the functional piston 22, the cylinder head assembly 40 and the inner wall of the cylinder 320, as shown in fig. 18. During the test, the fuel is burnt in the combustion chamber 60, and drives the functional piston 22 to lift in the cylinder, the functional piston 22 can drive the crankshaft 21 to rotate when moving up and down in the cylinder, so as to ensure the operation of the front end of the engine and the wheel system and the power output of the flywheel end of the engine during the test, because the crankshaft system 20 is also provided with at least one balance piston 24, each balance piston 24 is arranged in the cylinder of the cylinder, when the crankshaft 21 rotates, the balance piston 24 is driven to lift in the cylinder, the balance piston 24 is provided with a through vent hole 25, the vent hole 25 can effectively balance the internal and external air pressure of the balance piston 24, ensure the balance operation of the balance piston 24 in the cylinder, reduce the pumping loss generated by the functional piston in the intake stroke and the exhaust stroke, so as to reduce the test error, and can effectively simplify the structure of the crankshaft 21 while ensuring the balance rotation of the crankshaft, reducing the failure rate of crankshaft 21. Since the inner diameters of the cylinders in a multi-cylinder engine are substantially the same, the outer diameter of the balance piston 2 is the same as the outer diameter of the functional piston 22 and is matched to the diameter of the cylinder in order to match the cylinders of the multi-cylinder engine.

The upper end surface of the top of the piston is provided with a guide groove 26 which is formed by sinking downwards, and the vent hole 25 is positioned on the groove wall of the guide groove 26. Specifically, the diversion trench 26 may facilitate diversion of the oil such that the oil quickly flows back into the oil pan from the vent hole 25. The guide groove 26 extends from the center of the upper end surface of the piston crown to the edge of the piston crown. Specifically, the arrangement can enable the oil flowing to the upper end face of the top of the piston to quickly flow back into the oil pan from the vent hole 25, and errors generated in the experimental process are reduced. In this embodiment, the guiding groove 26 is a tapered groove, and the vent hole is located at the tip of the tapered groove. Specifically, the conical groove may facilitate the flow of the engine oil and the flow of the gas in the stroke chamber during upward movement of the balance piston 24. More specifically, the guiding groove 26 is a conical groove, and the vent 25 is located in the center of the conical groove. The maximum included angle between the conical groove generatrices is 115-125 degrees. Specifically, the conical groove at the angle can guide the engine oil conveniently, and meanwhile, damage to the piston pin 121 and other parts caused by machining of the conical groove can be effectively avoided.

In this embodiment, the balance piston 24 and the functional piston 22 have the same mass. Specifically, because the top of the balance piston 24 is provided with the vent hole 25 and the diversion trench 26, the arrangement of the vent hole 25 and the diversion trench 26 will reduce the mass of the balance piston 24, and in order to ensure that the mass of the balance piston 24 is the same as that of the functional piston, and in order to reduce errors generated in the experimental process, the mass of the balance piston 24 needs to be kept consistent with the arrangement of the diameter, the height, the stroke and the like of the functional piston, so that the density of the balance piston 24 in the balance cylinder 10 can be made greater than that of the functional piston, and the balance piston is balanced according to the processing amount of the diversion trench 26, and through the arrangement, the mass of the balance piston 24 can be made the same as that of the functional piston under the condition that the shapes of the balance piston 24 and the functional piston are kept consistent. The weight of the crank connecting rod 13 mechanism of each cylinder is never close, the balance of reciprocating inertia force and moment borne by the crankshaft 21 is ensured, and the problems of NVH (noise vibration harshness) and reliability such as large vibration of an engine, eccentric wear of a bearing bush and the like are avoided. In practice, the volume of the balance piston 24 is measured by digital-to-analog measurement with the volume and mass of the function piston known, the density of the balance piston 24 can be obtained with the same mass of the function piston 22 and the balance piston 24 in the cylinder, and the corresponding material is sought according to the density of the balance piston 24. In this embodiment, the thickness of the non-assembly portion of the balance piston 24 may also be increased to increase the mass of the balance piston 24, so as to achieve the technical effect of keeping the mass of the functional piston 22 consistent with that of the balance piston 24.

The thermodynamic single-cylinder engine 1000 is started by compression ignition, the mixed gas in the cylinder is ignited by the spark plug 40 to induce the partial combustion of the mixed gas in the combustion chamber 60, and the heat and the pressure released by the combusted partial mixed gas compress and heat the mixed gas in other areas of the combustion chamber 60, so that all the mixed gas in the combustion chamber 60 can self-ignite quickly. In order to realize the "compression ignition", referring to fig. 17, the top surface of the functional piston 22 in the present embodiment is provided with a concave pit 221, and the concave pit 221 serves as an ignition area of the mixture. The axis of the functional piston 22 passes through the recess 221, that is, the recess 221 is located at the center of the top surface of the functional piston 22, and the axis of the functional piston 22 is coaxial with the central axis of the recess 221, or is located near the center of the ignition region recess 221. The axes of the injector 30 and the ignition plug 40 are both passed through the recess so that the injection port of the injector 30 and the electrode of the ignition plug 40 are both opposed to the recess 221.

Referring specifically to fig. 18, the fuel injector 30 and the spark plug 40 are both disposed on the cylinder head 100 and extend into the combustion chamber 60. The injector 30 and the spark plug 40 are arranged at an angle, specifically, an included angle of 10 to 15 degrees is formed between the axial direction of the injector 30 and the axial direction of the spark plug 40, and in the embodiment, the included angle of the axis of the injector 30 and the axis of the spark plug 40 is 13 degrees. The fuel injector 30 is arranged in a central mode, and the injection pressure is not lower than 350 bar. The oil spray opening of the oil sprayer 30 is close to the edge of the concave pit 221, and preferably the axis of the oil sprayer 30 is tangent to the edge at the opening of the concave pit 221. By arranging the oil injection port of the oil injector 30 close to the edge of the pit 221, the fuel sprayed by the oil injector 30 contacts the pit wall of the pit 221, and the pit wall can guide the mixed gas to regularly flow along the pit wall surface of the ignition area to form regular tumble. The oil mist sprayed from the oil sprayer 30 is sprayed into the pit of the ignition region accurately, guided by the wall surface of the pit of the ignition region, and continuously mixed with fresh air to form a mixed gas with high tumble strength, and distributed near the spark plug 40, the mixed gas distributed near the electrode of the spark plug 40 of the ignition region is ignited rapidly under the discharge of the electrode and has high heat energy, and is diffused rapidly in the combustion chamber, and other local lean-burn mixed gas is compressed and heated to reach the self-ignition point for combustion.

Referring specifically to fig. 18, in the present embodiment, a cylinder pressure sensor 50 is further mounted on the cylinder head 100, and the cylinder pressure sensor 50 extends into the combustion chamber 60. By providing the cylinder pressure sensor 50 in the combustion chamber 60 to monitor the change in the in-cylinder pressure and performing closed-loop control, strong knocking of the engine is not caused, and the engine can be operated smoothly. By setting the ignition area and realizing local ignition, the lean-burn mixed gas in the combustion chamber 60 can be stably induced to generate spontaneous combustion in a transient state, and the combustion stability is ensured.

Through the above embodiment, the present application has the following beneficial effects or advantages:

1) the application provides a thermodynamics single cylinder engine 1000, solves and uses the thermodynamics single cylinder head 100 to build the hookup and the sealed problem that the thermodynamics engine that forms based on volume production multi-cylinder engine cylinder body relates to, has improved this kind of reliability of quick improved generation thermodynamics single cylinder engine 1000 to a low-cost development idea of low-cost thermodynamics engine cylinder head is provided.

2) The application provides a thermodynamics

single cylinder engine

1000, 1100 is constituteed to the cylinder head through at cylinder head 100 rear end stair structure 110 and apron 200 fall under the stair structure 230 location fit state, set up locating pin 3 and realize the accurate location of air intake and exhaust direction to pass through stud 1 and nut 2's combination fastening at cylinder head rear end face and apron 200 front end and realize the fastening of fore-and-aft direction, the restriction of above-mentioned two kinds of directions has promoted the joint strength between cylinder head 100 and the apron 200.

3) According to the thermodynamic single cylinder engine 1000 provided by the application, the top surface edge and the bottom surface edge of the step structure 110 at the rear end of the cylinder cover 100 in the cylinder cover assembly 1100 are provided with the glue storage chamfers 5, are matched with the glue storage chamfers 5 arranged on the edge of the front end surface section of the inverted step structure 230 of the cover plate 200 and the edge of the bottom plane, and are bonded and locked through the aluminum repairing agent 4, so that the direct connection strength of the cylinder cover 100 and the cover plate 200 is increased, and the assembly gap between the cylinder cover 100 and the cover plate 200 is filled; compared with silica gel, the aluminum repairing agent 4 can resist the pressure of the cooling liquid of the engine water jacket after being cured, and the sealing capability of the cylinder cover and the cover plate 200 is improved.

4) According to the thermodynamic single cylinder engine 1000 provided by the application, the cylinder cover assembly 1100 is provided with the leveling threaded holes 221 respectively on the convex ridges 220 of the cover plate 200, the span of the leveling threaded holes 221 is made as large as possible, and the cover plate 200 and the bottom surface of the cylinder cover can realize high integral flatness through adjustment and support of the leveling bolts 7, so that the subsequent metal repairing agent coating process is facilitated, and finally the cover plate 200 and the cylinder cover are fastened and connected.

5) The thermodynamic single cylinder engine 1000 provided by the application is after the cylinder head 100 and the cover plate 200 are fixed on the cylinder block 300 as required, the positioning pin 3 hole 231 preprocessed through the inverted step structure 230 of the cover plate 200 is punched and drilled step by step on the step structure 110 of the cylinder head 100, and is connected through the positioning pin 3, so that the accurate positioning of the cylinder head 100 and the cover plate 200 in the air intake and exhaust directions is ensured.

6) The application provides a thermodynamics single cylinder machine 1000 adopts single cylinder head 100 and the novel thermodynamics engine system that volume production multi-cylinder machine border combination formed, both possesses thermodynamics single cylinder machine 1000's advantages such as quick, with low costs, easily adjustment, available volume production multi-cylinder machine's current model machine border and experimental frock again, finally realizes the optimal effect of its cost, each side such as cycle and experimental effect to can be used for the optimization upgrading of volume production multi-cylinder machine combustion system.

7) The application provides a thermodynamics single cylinder engine 1000, be by single cylinder head 100 with the novel thermodynamics engine system that the combination of volume production multi-cylinder engine formed, follow the assembly with the volume production cylinder head gasket between single cylinder head 100 and the volume production cylinder head 300, avoid the cylinder head gasket to seal inefficacy, coolant liquid in the cylinder head 300 water jacket leaks and leads to the problem of oil-water mixture in the oil pan, solve fastening hookup and sealed problem between single cylinder head 100 and the multi-cylinder body from this, improve this thermodynamics engine's reliability.

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A thermodynamic single cylinder engine, comprising:

the cylinder body is provided with at least two cylinder barrels;

2. The thermodynamic single cylinder engine as claimed in claim 1, wherein: the cylinder cover and the cover plate are arranged side by side along the arrangement direction of the cylinder barrels, the butt joint ends of the cylinder cover and the cover plate are respectively provided with a first butt joint structure and a second butt joint structure which are matched with each other, the cylinder cover and the cover plate are positioned through the first butt joint structure and the second butt joint structure, and the cylinder cover and the cover plate are fixedly connected through threaded fasteners.

3. The thermodynamic single cylinder engine as claimed in claim 2, wherein: pin holes are formed in the first butt joint structure and the second butt joint structure, and positioning pins are inserted into the pin holes;

4. The thermodynamic single cylinder engine as claimed in claim 3, wherein: the first butt joint structure is of a step structure, and the second butt joint structure is of an inverted step structure; the step structure is in clearance fit with the butt joint surface of the inverted step structure; a chamfer is arranged at the edge of the step structure and/or the corner between the surface layer and the side surface; a chamfer is arranged at the edge of the inverted ladder structure and/or the folding angle between the surface layer and the side surface;

5. The thermodynamic single cylinder engine as claimed in claim 4, wherein: the surface layer gap between the step structure and the inverted step structure is 0.2-0.4 mm; the side gap between the step structure and the inverted step structure is 0.2-0.5 mm; and an aluminum repairing agent is filled in a gap between the butt joint end of the cylinder cover and the butt joint end of the cover plate.

6. The thermodynamic single cylinder engine as claimed in claim 2, wherein: the butt joint end of the cover plate is provided with a connecting side plate, and the cylinder cover is fixedly connected with the connecting side plate through the threaded fastener; the end face of the connecting side plate protrudes out of the end face of the butt joint end of the cover plate;

the cover plate is provided with convex ridges extending along the arrangement direction of the cylinder barrels, and the connecting side plate is connected to the convex ridges; and more than 3 leveling threaded holes for mounting leveling bolts are formed in the end face, far away from the assembly sealing surface, of each raised ridge.

7. The thermodynamic single cylinder engine as claimed in any one of claims 1 to 6, wherein: a cylinder body lubricating oil path is arranged in the cylinder body; and a second inlet oil duct, a middle oil duct and a camshaft lubricating oil path which are sequentially communicated are arranged in the cylinder cover, and the second inlet oil duct is communicated with the cylinder body lubricating oil path.

8. The thermodynamic single cylinder engine as claimed in claim 7, wherein: the second inlet oil passage has a horizontal direction projection component and a vertical direction projection component; the included angle between the axis of the second inlet oil duct and the vertical direction is 30-60 degrees;

the outer end of the second inlet oil passage is positioned on the bottom surface of the cylinder cover, and a transfer hole is formed in the outer end of the second inlet oil passage; the transfer hole is a waist-shaped hole; the depth of the transfer hole is 5 mm-8 mm.

9. The thermodynamic single cylinder engine as claimed in claim 7, wherein: the top of the cylinder cover is provided with a camshaft and a camshaft support used for mounting the camshaft, and the camshaft lubricating oil path is arranged in the camshaft support and the camshaft; the camshaft lubrication oil passage includes:

the air inlet and outlet side through oil channel is intersected with the middle oil channel structure;

10. The thermodynamic single cylinder engine as claimed in any one of claims 1 to 6, wherein: a cylinder body water jacket is arranged in the cylinder body; the cylinder cover is internally provided with a water inlet, a water outlet and a water jacket cavity which are communicated, and the water inlet and the water outlet are positioned at the bottom of the cylinder cover and are respectively communicated with the water jacket cavity and the cylinder body water jacket.

11. The thermodynamic single cylinder engine as claimed in claim 10, wherein: a combustion chamber top cover is arranged in the cylinder cover, and the water jacket chamber is arranged around the periphery of the combustion chamber top cover; the water inlet is close to the exhaust side of the cylinder head; the water outlet is close to the air inlet side of the cylinder cover;

the number of the water inlets and the number of the water outlets are more than one; the water inlet and the water outlet are arc-shaped strip-shaped holes; the inner diameters of the water inlet and the water outlet are different.

12. The thermodynamic single cylinder engine as claimed in any one of claims 1 to 6, wherein: the top surface of the balance piston is provided with an inward-sunken flow guide groove, and the vent hole is communicated with the flow guide groove; the flow guide groove is a conical groove, the flow guide groove extends from the center of the top surface of the balance piston to the edge, and the vent hole is located at the tip end of the conical groove.

13. The thermodynamic single cylinder engine as claimed in claim 12, wherein: the diameter of the excircle of the balance piston is the same as that of the functional piston; the balance piston and the functional piston have equal mass.

14. The thermodynamic single cylinder engine as claimed in any one of claims 1 to 6, wherein: the thermodynamic single cylinder engine further comprises:

and cylinder gaskets which are provided between the cylinder block and the cylinder head and between the cylinder block and the head plate to seal the assembly sealing surfaces of the cylinder block and the cylinder head and the head plate.

15. The thermodynamic single cylinder engine as claimed in any one of claims 1 to 6, wherein: the cylinder cover is provided with an oil injector, a spark plug and a cylinder pressure sensor, the oil injector, the spark plug and the cylinder pressure sensor all extend into the combustion chamber, and the oil injector and the spark plug are arranged at an angle;