Two-stroke heavy oil aviation piston engine

Abstract

The invention discloses a two-stroke heavy oil aviation piston engine, and belongs to the technical field of unmanned aerial vehicle engines, the two-stroke heavy oil aviation piston engine comprises an engine body, a spark plug, an exhaust pipe, a fuel oil supply system, a crank connecting rod mechanism, two pistons and an auxiliary heating system, the engine body is composed of a crankcase and two piston cylinders, and the two piston cylinders are horizontally and oppositely distributed on the two sides of the crankcase; the two sides of the crankcase are connected with the short output shaft and the long output shaft in a penetrating and coupling mode, and a rotating cavity opposite to the crankshaft connecting disc is formed in the crankcase. The opposed crankshaft connecting disc is provided with two crank throws in an opposed 180-degree working phase, and the structure of the opposed crankshaft connecting disc without a central shaft neck can reduce the centrifugal force of rotation and improve the operation stability; the crank throw is connected with the piston through a connecting rod, and the joint can rotate; the two pistons are respectively positioned in the two piston cylinders; and the auxiliary heating system is dispersedly arranged on the engine body, consists of a temperature switch and a heating rod, and is used for heating the purified oil-gas mixture provided by the fuel oil supply system.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle engines, and in particular to a two-stroke heavy oil aviation piston engine, which is a lightweight and efficient two-stroke piston engine designed for unmanned aerial vehicle applications. Background Art

[0002] With the rapid development and widespread application of UAV technology, higher requirements are placed on the performance of aircraft engines. Although traditional two-stroke piston engines have advantages such as simple structure and stable power output, their application in the field of UAVs is often limited by their heavy materials and complex structures. Especially in today's pursuit of lightweight and high efficiency, how to reduce engine weight and improve fuel efficiency has become an urgent problem to be solved.

[0003] Currently, most drone engines on the market are made of complex and heavy materials, which results in a relatively large overall engine weight, affecting the drone's load capacity and endurance. At the same time, the traditional crankshaft design has disadvantages such as large centrifugal force during rotation, obvious vibration, and large mass, which further reduces the stability and life of the engine.

[0004] In summary, a two-stroke heavy oil aviation piston engine made of lightweight materials and adopting a centerless crankshaft-piston opposed structure has been developed, which is of great significance for improving the overall performance of the UAV power system. Summary of the invention

[0005] The purpose of the present invention is to solve the problems existing in the above-mentioned UAV engine technology field and to provide a two-stroke heavy oil aviation piston engine, aiming to solve the problems existing in traditional engines and improve the overall performance of the UAV power system through the optimized design of materials and structures.

[0006] A two-stroke heavy oil aviation piston engine, characterized in that: two piston cylinders 3 are horizontally arranged on both sides of a crankcase 2, and a crank-connecting rod mechanism 8 passes through the crankcase 2;

[0007] The crank-connecting rod mechanism 8 is composed of a short output shaft 80, a crank pin 81, a crankshaft connecting rod 82, a crankshaft connecting plate 83, a long output shaft 84 and a connecting rod 85. The short output shaft 80 is fixedly connected to the crankshaft connecting plate 83, the crankshaft connecting plate 83 is fixedly connected to the crank pin 81, the crankshaft connecting plate 83 is fixedly connected to the crankshaft connecting rod 82, and the long output shaft 84 is fixedly connected to the crankshaft connecting plate 83; the short output shaft 80 passes through the short shaft shaft hole 244 and is connected to the lower crankcase 24. The shaft 81 passes through the long shaft shaft hole 227 and is connected to the crankcase 22; the crankshaft connecting plate 83, the crank pin 81 and the crankshaft connecting rod 82 constitute a crank, and the crankshaft connecting plate 83, the crank pin 81 and the crankshaft connecting rod 82 constitute a crank, and the working phases of the two cranks differ by 180°. The connecting rods 85 on both sides are rotatably connected to the cranks on both sides through the shaft holes on one side of the connecting rod big end 832; the connecting rod 85 is rotatably connected to the piston pin shaft 92 through the shaft hole on one side of the connecting rod small end 831.

[0008] The crankcase 2 is provided with a heating rod 5 and a temperature switch 23 .

[0009] The cylinder body of the piston cylinder 3 is also provided with a heating rod (5) and a temperature switch 23.

[0010] The inner wall of the crankcase 2 is chrome-plated, and the piston (9) is made of forged aluminum alloy material.

[0011] The fuel supply system 7 is composed of an air intake box 71, a polyamide resin tube I72, a nut 73, a clamping ring 74, a carburetor 75, a polyamide resin tube II76, and an air filter 77, wherein the inner walls of the polyamide resin tube I72 and the polyamide resin tube II76 are provided with internal threads, the air intake box 71 is connected to the polyamide resin intake pipe I72 by threaded fastening, the air inlet of the carburetor 75 is connected to the resin intake pipe I72 by a nut 73 and a clamping ring 74, the carburetor 75 is connected to the polyamide resin tube II76 by threaded fastening, and the air filter box 77 is connected to the polyamide resin tube II76 by a nut 73 and a clamping ring 74.

[0012] In summary, the two-stroke heavy oil aviation piston engine provided by the present invention has the following beneficial effects and advantages:

[0013] The fuel supply system of the present invention can provide a clean oil-gas mixture for the engine. The pipe material used in the system is polyamide resin, which has the characteristics of oil resistance and light weight, which can effectively reduce the overall weight of the engine and increase its service life.

[0014] In order to improve the strength of the crankcase and achieve lightness, the inner wall of the crankcase is chrome-plated for strengthening, and the crankcase is processed and manufactured using lightweight aluminum alloy material to achieve lightness.

[0015] The fuel used in the present invention is aviation heavy oil, which has high kinematic viscosity and surface tension, and poor atomization effect in low temperature environment. In addition, the saturated vapor pressure of heavy oil is lower than that of gasoline, but its boiling point is higher, and its evaporation performance is poor. The above characteristics will be extremely obvious in low temperature environment. Therefore, multiple heating rods are provided on the crankcase and the piston cylinders on both sides, and a total temperature switch is provided to control the heating. When working, the oil-gas mixture is heated to optimize the performance of the engine cold start.

[0016] When working, the centrifugal force and vibration of the crankshaft of the engine are large, so the center-less journal structure is adopted to reduce the centrifugal force of the crankshaft when working and increase the stability of the crankshaft. At the same time, the structure of the center-less journal crankshaft components in the present invention is separable, and each component can be processed separately, which improves the accuracy of the crankshaft and reduces the processing cost.

[0017] The opposed crankshaft connecting plate structure of the crank-connecting rod mechanism in the present invention has a central main journal compared to the traditional crankshaft, which plays a role in power transmission and balance, but it is often large in mass, resulting in an increase in the overall mass of the engine. By removing the central main journal and using a crankshaft connecting rod made of lightweight materials, the mass of the crankshaft can be effectively reduced, effectively achieving overall lightweighting of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a two-stroke heavy oil aviation piston engine of the present invention;

[0019] Figure 2 It is a cross-sectional view A of the internal structure of a two-stroke heavy oil aviation piston engine of the present invention;

[0020] Figure 3 It is a cross-sectional view B of the internal structure of a two-stroke heavy oil aviation piston engine of the present invention;

[0021] Figure 4 It is a schematic diagram of the specific structure of a fuel supply system of a two-stroke heavy oil aviation piston engine of the present invention;

[0022] Figure 5 It is a schematic diagram of the crankcase connection structure of a two-stroke heavy oil aviation piston engine of the present invention;

[0023] Figure 6 It is a schematic diagram of a crank-connecting rod mechanism of a two-stroke heavy oil aviation piston engine of the present invention;

[0024] Figure 7 A is a three-dimensional structural schematic diagram of an upper crankcase of a two-stroke heavy oil aviation piston engine of the present invention;

[0025] Figure 8This is a three-dimensional structural schematic diagram B of an upper crankcase of a two-stroke heavy oil aviation piston engine of the present invention;

[0026] Fig. 9 It is a schematic diagram of the vertical upper structure of the lower crankcase of a two-stroke heavy oil aviation piston engine of the present invention;

[0027] Fig.10 It is a schematic diagram of the specific structure of a piston cylinder of a two-stroke heavy oil aviation piston engine of the present invention;

[0028] Fig.11 It is a top view of the external structure of a piston cylinder of a two-stroke heavy oil aviation piston engine of the present invention;

[0029] Fig.12 It is a schematic diagram of the specific structure of a piston head of a two-stroke heavy oil aviation piston engine of the present invention;

[0030] Fig.13 The present invention is a schematic diagram of the specific structure of a connecting rod of a crank-connecting rod mechanism of a two-stroke heavy oil aviation piston engine.

[0031] In the attached picture:

[0032] 1. Engine body;

[0033] 2. Crankcase; 21. Bolts; 22. Upper crankcase; 23. Temperature switch; 24. Lower crankcase; 25. Heating rod; 221. Upper and lower bolt holes Ⅰ; 222. Temperature switch slot; 223. Side bolt hole Ⅱ; 224. Oil inlet Ⅰ; 225. Positioning slot; 226. Heating rod hole Ⅰ; 227. Long shaft hole; 242. Positioning column; 243. Oil inlet Ⅱ; 244. Short shaft hole;

[0034] 3. Piston cylinder; 31. Inlet hole Ⅰ; 32. Exhaust hole; 33. Combustion chamber; 34. Cylinder head; 35. Inlet hole Ⅱ; 36. Inlet hole Ⅲ; 38. Heating rod hole Ⅱ;

[0035] 4. Spark plug; 6. Exhaust pipe;

[0036] 7. Fuel supply system; 71. Air intake box; 72. Polyamide resin pipe I; 73. Nut; 74. Clamping ring; 75. Carburetor; 76. Polyamide resin pipe II; 77. Air filter box;

[0037] 8. Crank-connecting rod mechanism; 80. Short output shaft; 81 Crank pin; 82. Crankshaft connecting rod; 83. Crankshaft connecting plate; 84. Long output shaft; 85. Connecting rod; 831. Small end of connecting rod; 832. Big end of connecting rod;

[0038] 9. Piston; Piston head 90; 91. Piston ring; 92. Piston pin; 93. Pin limiting ring 941. Ring groove I; 942. Ring groove II; 943. Pin hole. DETAILED DESCRIPTION

[0039] The following will be combined with the attached Figure 1-13 The advantages, purposes and features of the present invention are described more clearly and completely in the following specific implementation modes. It should be noted that the embodiments described below are only a part of all the embodiments of the present invention, but not all the embodiments.

[0040] Example 1

[0041] A two-stroke heavy oil aviation piston engine in the present invention comprises: an engine body 1, a spark plug 4, an exhaust pipe 6, a fuel supply system 7, a crank connecting rod mechanism 8, two pistons 9 and an auxiliary heating system, wherein: the exhaust pipe 6 and the fuel supply system 7 are fixedly connected to the engine body 1;

[0042] The engine body 1 includes a crankcase 2, two piston cylinders 3 and fastening parts. The two piston cylinders 3 are horizontally oppositely distributed on both sides of the crankcase 2. The crankcase 2 and the piston cylinders 3 are fastened with bolts through the side bolt holes II223 structure; the auxiliary heating system is dispersed on the crankcase 2 and the piston cylinders 3 on both sides.

[0043] The auxiliary heating system includes: a temperature switch 23 and a heating rod 25 . The temperature switch 23 can control the heating of the heating rod 25 .

[0044] The crankcase 2 comprises: an upper crankcase 22, a lower crankcase 24 and a bolt 21. The upper crankcase 22 and the lower crankcase 24 are both provided with four corresponding upper and lower bolt holes I221 and are fastened together by the bolts 21. The internal space formed by the two is provided with a crank-connecting rod mechanism 8; the oil inlet I224 on the upper crankcase 22 and the oil inlet II243 on the lower crankcase 24 together constitute the total oil inlet of the crankcase 2;

[0045] The upper crankcase 22 is also provided with a positioning groove 225, a temperature switch groove 222, four heating rod holes I226 and a long shaft hole 227; the lower crankcase 24 is also provided with a positioning column 242, four heating rod holes I226 and a short shaft hole 244; the positioning groove 225 and the positioning column 242 play a limiting role in the fixed connection between the upper crankcase 22 and the lower crankcase 24, the temperature switch 23 is fixed to the temperature switch groove 222 by a flat head screw, and the eight heating rod holes I226 are fastened to the heating rod 25 by threads.

[0046] An exhaust port 32 is provided on one side of the piston cylinder 3, and the exhaust pipe 6 is fastened to the exhaust port 32 by bolts. The two pistons 9 move in the axial direction of the two piston cylinders 3 respectively. The piston cylinder 3 and the cylinder head 34 form a combustion chamber 33, and the spark plug 4 is fixedly connected to the spark plug hole on the top of the cylinder head 34 by threads; the piston cylinder 3 is also provided with an intake hole Ⅰ31, an intake hole Ⅱ35, an intake hole Ⅲ36 and 6 heating rod holes Ⅱ38, so the two piston cylinders 3 on both sides have a total of 12 heating rod holes Ⅰ226 that are fastened to the heating rod 25 by threads.

[0047] The crank-connecting rod mechanism 8 comprises: a short output shaft 80, a crank pin 81, a crankshaft connecting rod 82, a crankshaft connecting plate 83, a long output shaft 84 and a connecting rod 85, wherein: the short output shaft 80 is fixedly connected to the crankshaft connecting plate 83, the crankshaft connecting plate 83 is fixedly connected to the crankshaft pin 81, the crankshaft connecting plate 83 is fixedly connected to the crankshaft connecting rod 82, and the long output shaft 84 is fixedly connected to the crankshaft connecting plate 83; the short output shaft 80 passes through the short shaft shaft hole 244 and is axially connected to the lower crankcase 24; the long output shaft 84 is fixedly connected to the crankshaft connecting plate 83; The output shaft 81 passes through the long shaft shaft hole 227 and is connected to the crankcase 22; the crankshaft connecting plate 83, the crank pin 81 and the crankshaft connecting rod 82 constitute a crank, and the crankshaft connecting plate 83, the crank pin 81 and the crankshaft connecting rod 82 constitute a crank, and the working phases of the two cranks differ by 180°. The connecting rods 85 on both sides are rotatably connected to the cranks on both sides through the shaft holes on one side of the connecting rod big end 832; the connecting rod 85 is rotatably connected to the piston pin shaft 92 through the shaft hole on one side of the connecting rod small end 831.

[0048] The piston 9 includes: a piston head 90, a piston ring 91, a piston pin 92, and a pin limit ring 93, wherein the piston head 90 is provided with a ring groove Ⅰ941, a ring groove Ⅱ942, and a pin hole 943, and the piston ring 91 is fixed in the ring groove Ⅱ942 at the upper end of the piston 9; the piston pin 92 is fixed to the inside of the piston head 90 through the ring grooves Ⅰ941 and the pin hole 943 on both sides by the pin limit ring 93, and the ring groove Ⅰ941 is arranged inside the pin hole 943.

[0049] The fuel supply system 7 comprises: an air intake box 71, a polyamide resin pipe I 72, a nut 73, a clamping ring 74, a carburetor 75, a polyamide resin pipe II 76, and an air filter 77, wherein: the polyamide resin pipe I 72 is a bent pipe, the polyamide resin pipe II 76 is a straight pipe, and the inner wall thereof is provided with an internal thread, the air intake box 71 is connected to the outer side of the polyamide resin air intake pipe I 72 by threaded fastening, the air inlet of the carburetor (75) is connected to the inner side of the resin air intake pipe I 72 by a nut 73 and a clamping ring 74, the carburetor 75 is connected to the outer side of the polyamide resin pipe II 76 by threaded fastening, and the air filter box 77 is connected to the inner side of the polyamide resin pipe II 76 by a nut 73 and a clamping ring 74 and the polyamide resin air intake pipe I 72.

[0050] In actual manufacturing, the inner wall of the crankcase 2 is chrome-plated, and the piston 9 is made of forged aluminum alloy.

[0051] The present invention provides a two-stroke heavy oil aviation piston engine, the working principle of which is as follows:

[0052] During operation, in the fuel supply system 7, the air is first filtered through the air intake box 71, and then the air passes through the carburetor 75 to form an oil-gas mixture, and finally the oil-gas mixture is filtered for a second time through the air filter box 77 to obtain a relatively clean oil-gas mixture; the pipe material used in the present invention is polyamide resin, which has the characteristics of oil resistance and light weight, which can effectively reduce the overall weight of the engine and increase its service life.

[0053] When working, the centrifugal force and vibration of the crankshaft of the engine are large, so the center-less journal structure is adopted to reduce the centrifugal force of the crankshaft when working and increase the stability of the crankshaft. At the same time, the structure of the center-less journal crankshaft components in the present invention is separable, and each component can be processed separately, which improves the accuracy of the crankshaft and reduces the processing cost.

[0054] When working, the fuel used by this engine is aviation heavy oil. Heavy oil has high kinematic viscosity and surface tension, and poor atomization effect in low temperature environment. In addition, the saturated vapor pressure of heavy oil is lower than that of gasoline and its boiling point is higher, and its evaporation performance is poor. The above characteristics will be extremely obvious in low temperature environment. Therefore, multiple heating rods 25 are provided on the crankcase 2 and the piston cylinders 3 on both sides, and a total temperature switch 23 is provided to control heating. When working, the oil-gas mixture is heated to optimize the performance of engine cold start.

[0055] In actual use, in order to improve the strength of the crankcase 2 and achieve lightweight, chrome plating is mainly performed on the inner wall of the crankcase 2 to achieve strengthening, and aluminum alloy lightweight material is used for the crankcase 2 to achieve lightweight; the piston head 90 is manufactured by a casting process using lightweight aluminum alloy.

[0056] During operation, the oil and gas compounds in the combustion chamber 33 are ignited by the spark plug 4, and the oil and gas compounds are burned to expand the gas in the combustion chamber 33 to drive the two pistons 9 to reciprocate in the two piston cylinders 3; two crankshafts are provided on the opposing crankshaft connecting plates 82 with opposing working phases of 180°, and two connecting rods 83 are respectively provided between the two crankshafts and the two pistons 9. Therefore, under the reciprocating motion of the two pistons 9, the crankshaft connecting plates 82 will be driven to rotate in a circle through the two connecting rods 83, thereby driving the short output shaft 80 and the long output shaft 81 integrally connected thereto to rotate, thereby outputting a torque.

Claims

1. A two-stroke heavy oil aviation piston engine, characterized in that: Two piston cylinders (3) are horizontally arranged on both sides of the crankcase (2), and a crank-connecting rod mechanism (8) passes through the crankcase (2); The crank-connecting rod mechanism (8) is composed of a short output shaft (80), a crank pin (81), a crankshaft connecting rod (82), a crankshaft connecting plate (83), a long output shaft (84) and a connecting rod (85); the short output shaft (80) is fixedly connected to the crankshaft connecting plate (83), the crankshaft connecting plate (83) is fixedly connected to the crank pin (81), the crankshaft connecting plate (83) is fixedly connected to the crankshaft connecting rod (82), and the long output shaft (84) is fixedly connected to the crankshaft connecting plate (83); the short output shaft (80) passes through the short shaft shaft hole (244) and is axially connected to the lower crankcase (24); The long output shaft (81) passes through the long shaft shaft hole (227) and is connected to the crankcase (22); the crankshaft connecting plate (83), the crank pin (81) and the crankshaft connecting rod (82) form a crank, and the crankshaft connecting plate (83), the crank pin (81) and the crankshaft connecting rod (82) form a crank, and the working phases of the two cranks differ by 180 degrees. The connecting rods (85) on both sides are rotatably connected to the cranks on both sides through the shaft holes on one side of the connecting rod big end (832); the connecting rod (85) is rotatably connected to the piston pin shaft (92) through the shaft hole on one side of the connecting rod small end (831).

2. A two-stroke heavy oil aviation piston engine according to claim 1, characterized in that: The crankcase (2) is provided with a plurality of heating rods (5) and a temperature switch (23) on its body.

3. A two-stroke heavy oil aviation piston engine according to claim 1, characterized in that: A heating rod (5) and a temperature switch (23) are also provided on the cylinder body of the piston cylinder (3).

4. The two-stroke heavy oil aviation piston engine according to claim 1, 2 or 3, characterized in that: The inner wall of the crankcase (2) is chrome-plated, and the piston (9) is made of forged aluminum alloy material.

5. The two-stroke heavy oil aviation piston engine according to claim 4, characterized in that: The fuel supply system (7) is composed of an air intake box (71), a polyamide resin pipe I (72), a nut (73), a clamping ring (74), a carburetor (75), a polyamide resin pipe II (76), and an air filter (77), wherein the inner walls of the polyamide resin pipe I (72) and the polyamide resin pipe II (76) are provided with internal threads, the air intake box (71) is connected to the polyamide resin air intake pipe I (72) by threaded fastening, the air inlet of the carburetor (75) is connected to the resin air intake pipe I (72) by a nut (73) and a clamping ring (74), the carburetor (75) is connected to the polyamide resin pipe II (76) by threaded fastening, and the air filter box (77) is connected to the polyamide resin pipe II (76) by a nut (73) and a clamping ring (74) and the polyamide resin air intake pipe I (72).

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