Ignition timing structure of two-stroke multi-cylinder aero-engine

Abstract

According to the ignition timing structure of the two-stroke multi-cylinder aero-engine, the aero-engine is provided with a magnetor, the magnetor is composed of a magnetic steel rotor and a pair of magnetic electrodes, the magnetic steel rotor is installed on a crankshaft, and the pair of magnetic electrodes are symmetrically installed on the two sides of the magnetic steel rotor; the magnetic steel rotor is in a disc shape, a pair of permanent magnets is symmetrically embedded in the outer circle face of the magnetic steel rotor, and N poles and S poles of the permanent magnets are arranged in the clockwise direction. The magnetic electrode is composed of a silicon steel sheet and a coil, the silicon steel sheet is in an n shape and is provided with a short left supporting leg and a long right supporting leg, and the coil is fixed to the left supporting leg and points to the circle center of the magnetic steel rotor. When the ignition advance angle is adjusted, the left edge of the right supporting leg is aligned with the right edge of the N pole of the permanent magnet, and the right edge of the left supporting leg is close to the left edge of the N pole of the permanent magnet. According to the ignition timing structure, timing marks do not need to be carved on parts, the influence of part machining errors on ignition timing is eliminated, and the accuracy and stability of ignition timing are improved.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and in particular to an ignition timing structure of a two-stroke multi-cylinder aeroengine. Background Art

[0002] A two-stroke aircraft engine has multiple cylinders arranged in opposition. When working, the piston in each cylinder requires a magnetic motor to provide ignition timing.

[0003] See attached Figure 1 . The existing magnetic motor 1 is mainly composed of a magnetic steel rotor 11 and a stator disk 9. The stator disk 9 is installed on the crankcase, and the magnetic steel rotor is installed on the crankshaft. Permanent magnets are installed in the magnetic motor rotor 11, and a protruding trigger block 115 is provided on the edge of the magnetic steel rotor 11. Two types of coils are installed on the stator disk 9, one is a power generation coil 91 located in the inner cavity of the magnetic motor rotor, which is used to cut magnetic lines of force to generate electricity; the other is an induction coil 92 located on the outside of the magnetic steel rotor. When the magnetic steel rotor 11 rotates with the crankshaft, the trigger block 115 approaches the induction coil 92, and an ignition signal is generated in the induction coil 92.

[0004] During operation, the piston must ignite the mixed oil and gas in the cylinder in advance through the spark plug before reaching the top dead center. In order to facilitate the determination of the ignition advance angle and the ignition time, a timing mark is provided on the edge of the magnetic steel rotor, and a timing scale line is provided on the crankcase. When the piston is at the top dead center, the timing mark is aligned with the timing scale line. However, this ignition timing method is only applicable to single-cylinder engines, not to multi-cylinder two-stroke aircraft engines, and the accuracy of the ignition timing is largely limited by the processing accuracy of parts such as the magneto, crankshaft connecting rod, and piston. If a certain part is out of tolerance, even if the timing mark is aligned with the timing scale line, the ignition timing is inaccurate. It is known that the ignition timing has a significant impact on the combustion and work of the mixed oil and gas in the cylinder. Too early ignition or too late ignition will affect the output power of the engine. Summary of the invention

[0005] In order to overcome the deficiencies in the background technology, the present invention discloses an ignition timing structure of a two-stroke multi-cylinder aircraft engine, the purpose of which is:

[0006] 1. Suitable for adjusting the ignition timing of multi-cylinder aircraft engines;

[0007] 2. Eliminate the influence of component processing errors on ignition timing and improve the accuracy of ignition timing.

[0008] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0009] An ignition timing structure for a two-stroke multi-cylinder aircraft engine, the aircraft engine having a magneto, the magneto consisting of a magnetic steel rotor and a pair of magnetic electrodes, the magnetic steel rotor being mounted on a crankshaft, the pair of magnetic electrodes being symmetrically mounted on both sides of the magnetic steel rotor; the magnetic steel rotor being disc-shaped, a pair of permanent magnets being symmetrically embedded on the outer circumferential surface of the magnetic steel rotor, the N pole and the S pole of the permanent magnet being arranged in a clockwise direction; the magnetic electrode consisting of a silicon steel sheet and a coil, the silicon steel sheet being η-shaped, having a shorter left leg and a longer right leg, the coil being fixed on the left leg and pointing to the center of the magnetic steel rotor; when adjusting the ignition advance angle, the left edge of the right leg is aligned with the right edge of the permanent magnet's N pole, and the right edge of the left leg is close to the left edge of the permanent magnet's N pole.

[0010] To further improve the technical solution, a hub is installed on the crankshaft, a connecting disk is provided on the hub, and a plurality of rivet holes are evenly distributed along the circumference of the connecting disk; an arc-shaped connecting hole corresponding to the connecting hole is provided on the magnetic steel rotor, and the magnetic steel rotor is installed on the connecting disk with an adjustable angle by rivets.

[0011] To further improve the technical solution, an external spline is provided on the output shaft of the crankshaft, an internal spline is provided in the propeller hub, and the propeller hub is installed on the output shaft of the crankshaft through the spline structure.

[0012] To further improve the technical solution, a fixing plate is installed on the crankcase of the aircraft engine, and a plurality of threaded holes are arranged on the fixing plate; a plurality of long holes are arranged on the silicon steel sheet, and a pair of magnetic electrodes are adjustably mounted on the fixing plate by bolts.

[0013] After implementing the above technical solution, compared with the background technology, the beneficial effects produced by the present invention are:

[0014] 1. This ignition timing structure is suitable for two-cylinder, four-cylinder, eight-cylinder and other two-stroke aircraft engines. Only the timing of one cylinder needs to be adjusted to achieve the timing adjustment of all cylinders;

[0015] 2. This timing structure does not require the engraving of timing marks on parts, eliminating the influence of machining errors of parts such as magneto, crankshaft, connecting rod, piston, etc. on ignition timing, thus improving the accuracy and stability of ignition timing;

[0016] 3. The coil can generate electricity and provide ignition signals for the spark plugs on any cylinder, without the need for pairing;

[0017] 4. This ignition timing structure reduces the magnetic gap, improves the power generation efficiency of the coil and the strength of the ignition signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Attached Figure 1 Shown is a schematic diagram of the structure of an existing magnetic motor.

[0019] Attached Figure 2Shown is a perspective view of a horizontally opposed two-stroke aircraft engine.

[0020] Attached Figure 3 Shown is a front view of a horizontally opposed two-stroke aircraft engine.

[0021] Attached Figure 4 Shown is a schematic diagram of the position of the piston before the crankshaft rotates.

[0022] Attached Figure 5 Shown is a schematic diagram of the structure of a magnetic motor.

[0023] Attached Figure 6 Shown is a schematic diagram of the installation structure of the magnetic motor on the fixed plate and the hub.

[0024] Attached Figure 7 The attached Figure 2 Enlarged view of point P in the middle.

[0025] Attached Figure 8 Shown is a schematic diagram of the magnetic steel rotor and magnetic electrode timing.

[0026] Attached Fig. 9 The diagram shows the position of the piston after the crankshaft rotates 180°.

[0027] In the attached drawings: 1. magnetic motor; 11. magnetic steel rotor; 111. disk body; 112. permanent magnet; 113. arc-shaped connecting hole; 114. weight reduction structure; 115. trigger block; 12. magnetic electrode; 121. silicon steel sheet; 1211. left leg; 1212. right leg; 122. coil; 2. dial indicator; 3. hub; 31. connecting disk; 32. rivet hole; 33. internal spline; 4. bolt; 5. fixing plate; 6. crankshaft; 61. connecting rod; 62. piston; 7. cylinder; 8. crankcase; 9. stator disk; 91. generating coil; 92. induction coil. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. It should be noted that in the description of the present invention, the terms "front", "rear", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal connection of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0029] See attached Figure 2 and attached Figure 3 . Figure 2 and attached Figure 3 It can be seen that a horizontally opposed two-stroke aircraft engine has four cylinders 7, which are horizontally opposed. The cylinder diameter is 66 mm and the stroke of the piston is 40 mm.

[0030] See attached Figure 4 . Accordingly, the crankshaft 6 located in the crankcase 8 has four connecting rods 61, and a piston 62 is installed at the small end of the connecting rod 61. When the two pistons 62 on the left are at the top dead center, the two pistons 62 on the right are at the bottom dead center. In order to detect whether the piston 62 reaches the ignition advance angle, an external thread is provided on the sleeve rod of the dial gauge 2, and the dial gauge 2 is screwed into the spark plug hole of the 1# cylinder 7, and the probe of the dial gauge 2 is against the top of the piston 62. The crankshaft 6 also has two output shafts, and an external spline is provided on one of the output shafts.

[0031] See attached Figure 2 , Attachment Figure 3 , Attachment Figure 5 The magnetic motor 1 is composed of a magnetic steel rotor 11 and a pair of magnetic electrodes 12 . The magnetic steel rotor 11 is mounted on the crankshaft 6 , and the pair of magnetic electrodes 12 are symmetrically mounted on both sides of the magnetic steel rotor 11 .

[0032] The magnetic steel rotor 11 has a disc-shaped disk body 111, and the material of the disk body 111 is aluminum alloy. A pair of permanent magnets 112 are symmetrically embedded on the outer circumferential surface of the disk body 111 with the axis of the disk body 111 as the center, and the N pole and S pole of the permanent magnet 112 are arranged in a clockwise direction. Eight arc-shaped connecting holes 113 are evenly distributed along the circumference of the magnetic steel rotor 11, and the arc-shaped connecting holes 113 are centered on the axis of the disk body 111. In addition, a weight reduction structure 114 is symmetrically arranged on the magnetic steel rotor 11.

[0033] The magnetic electrode 12 is composed of a silicon steel sheet 121 and a coil 122. The silicon steel sheet 121 is η-shaped, with a shorter left leg 1211 and a longer right leg 1212. The left leg 1211 is parallel to the right leg 1212. The coil 122 is fixed on the left leg 1211 and points to the center of the magnetic steel rotor 11.

[0034] See attached Figure 6 A fixing plate 5 is mounted on the crankcase 8, and four threaded holes are arranged on the fixing plate 5. The fixing plate 5 is used to mount a pair of magnetic electrodes 12. Two elongated holes arranged along the radial direction of the magnetic steel rotor 11 are arranged on the silicon steel sheet 121. The pair of magnetic electrodes 12 are mounted on the fixing plate 5 by bolts 4. The installation distance of the magnetic electrodes 12 relative to the magnetic steel rotor 11 can be adjusted through the elongated holes.

[0035] The hub 3 is mounted on the crankshaft 6, and an internal spline 33 is provided in the hub 3. The hub 3 is mounted on the output shaft of the crankshaft 6 through the spline structure. A connecting disk 31 is provided on the hub 3, and eight rivet holes 32 are evenly distributed along the circumference of the connecting disk 31. The eight rivet holes 32 are arc holes with the axis of the hub 3 as the center. The magnetic steel rotor 11 is coaxially mounted on the connecting disk 31, and rivets are inserted into the arc connecting hole 113 of the magnetic steel rotor 11 and the arc hole of the connecting disk 31 to fix the magnetic steel rotor 11 on the hub 3, so that the installation angle of the magnetic steel rotor 11 on the hub 3 can be adjusted. Since the hub 3 is mounted on the crankshaft 6 through the spline structure, the installation angle is also the installation angle of the magnetic steel rotor 11 on the crankshaft 6.

[0036] Before adjusting the ignition timing, first determine the ignition advance angle of the crankshaft. Figure 4 , put the dial gauge 2 into the spark plug hole of the 1# cylinder 7 of the aircraft engine, rotate the crankshaft 6 clockwise to make the piston 62 at the top dead center, and adjust the dial gauge 2 to zero. Then rotate the crankshaft 6 counterclockwise until the dial gauge 2 needle rotates counterclockwise to a certain value. It is worth noting that this value is calculated in reverse based on the ignition advance angle set by the aircraft engine. In this embodiment, the dial gauge needle rotates counterclockwise to 3.3mm.

[0037] See attached Figure 7Then adjust the installation angle of the magnetic steel rotor 11 on the crankshaft 6 so that the left edge of the right leg 1212 is aligned with the right edge of the permanent magnet 112N pole, and the right edge of the left leg 1211 is close to the left edge of the permanent magnet 112N pole. Finally, use rivets to fix the magnetic steel rotor 11 on the hub 3 to complete the ignition timing of the piston 62 in the 1# cylinder 7.

[0038] See attached Figure 8 . When the piston 62 in the 1# cylinder 7 moves upward and is 3.3 mm away from the top dead center, the crankshaft 6 is in the position of the ignition advance angle. At this time, the magnetic steel rotor 11 is rotated to align the right edge of the permanent magnet's N pole with the left edge of the right leg 1212, and the left edge of the permanent magnet's N pole is close to the right edge of the left leg 1211. At this time, the magnetic field strength at the left leg 1211 suddenly increases, and a stronger ignition signal is generated in the coil 122, and the spark plug on the 1# cylinder begins to ignite in advance. Since the piston movement in the 1# cylinder is symmetrical with the piston movement in the 2# cylinder, the coil can be connected to the spark plugs on the 1# cylinder and the 2# cylinder to ignite the spark plugs on the 1# cylinder and the 2# cylinder at the same time.

[0039] See attached Fig. 9 After the crankshaft 6 rotates 180° clockwise, the pistons 62 in the 3# cylinder and the 4# cylinder move upward and are 3.3mm away from the top dead center. At this time, the permanent magnet 112 on the magnetic steel rotor 11 turns to the other magnetic electrode 12 opposite, and the coil 122 of the magnetic electrode 12 is connected to the spark plugs on the 3# cylinder and the 4# cylinder. When the left edge of the right leg 1212 is aligned with the right edge of the permanent magnet 112N pole, and the left edge of the permanent magnet 112N pole is close to the right edge of the left leg 1211, the spark plugs on the 3# cylinder and the 4# cylinder ignite at the same time.

[0040] In fact, every time the crankshaft rotates 180°, the spark plugs on the four cylinders ignite at the same time, but the ignition does not work for the two cylinders where the piston is at the bottom dead center. The advantage of this design is that the ignition signal generated by the coil can make the spark plug on any cylinder generate sparks after being pressurized by the high-voltage package, and there is no need for pairing.

[0041] Again refer to the attached Figure 1. The existing magnetic steel rotor 11 is clamped with a magnet, and a protruding trigger block 115 is provided on the edge of the magnetic steel rotor 11. The ignition principle is: when the trigger block 115 is not close to the induction coil 92, the magnetic steel rotor 11 has a relatively weak magnetic field strength, and the induction coil 92 induces a lower electrical signal at this time. When the trigger block 115 approaches the induction coil 92, the gap between the induction coil 92 and the magnetic steel rotor 11 suddenly becomes smaller, and the magnetic field strength suddenly increases, and the induction coil 92 can induce a higher electrical signal, thereby forming an ignition signal. Since the difference between the higher electrical signal and the lower electrical signal is small, the ignition signal is not obvious, and the engine may not ignite.

[0042] Compared to the attached Figure 1 In the magnetic motor, the magnetic steel rotor 11 of the present invention is not provided with a trigger block. The long strip hole and the bolt 4 can make the magnetic electrode 12 closer to the magnetic steel rotor 11, thereby reducing the magnetic gap and improving the power generation efficiency of the coil 122 and the strength of the ignition signal. More importantly, the coil of the present invention can both generate electricity and generate an ignition signal. Since the disk 111 does not have magnetic conductivity, when the permanent magnet 112 is not close to the coil 122, the coil 122 basically will not induce an electrical signal. When the permanent magnet 112 is close to the coil 122, the coil 122 can induce a very high electrical signal. Since the signal difference is obvious, an obvious ignition signal can be formed to ensure smooth ignition of the engine.

[0043] This timing structure is applicable to two-stroke aircraft engines such as two-cylinder, four-cylinder, and eight-cylinder engines. The timing of all cylinders can be adjusted by adjusting the timing of only one cylinder. More importantly, this timing structure does not require timing marks to be engraved on parts, eliminates the influence of machining errors of parts such as magneto 1, crankshaft 6, connecting rod 61, piston 62 on ignition timing, and improves the accuracy and stability of ignition timing.

[0044] Although the embodiments of the present invention have been shown and described, it is understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. An ignition timing structure for a two-stroke multi-cylinder aircraft engine, the aircraft engine having a magneto, characterized in that: The magnetic motor consists of a magnetic steel rotor and a pair of magnetic electrodes. The magnetic steel rotor is installed on the crankshaft, and the pair of magnetic electrodes are symmetrically installed on both sides of the magnetic steel rotor. The magnetic steel rotor is disc-shaped, and a pair of permanent magnets are symmetrically embedded on the outer circumferential surface of the magnetic steel rotor, and the N pole and S pole of the permanent magnet are arranged in a clockwise direction; the magnetic electrode is composed of a silicon steel sheet and a coil. The silicon steel sheet is η-shaped, with a shorter left leg and a longer right leg. The coil is fixed on the left leg and points to the center of the magnetic steel rotor. When adjusting the ignition advance angle, the left edge of the right leg is aligned with the right edge of the permanent magnet's N pole, and the right edge of the left leg is close to the left edge of the permanent magnet's N pole.

2. The ignition timing structure of a two-stroke multi-cylinder aircraft engine as claimed in claim 1, characterized in that: A hub is installed on the crankshaft, a connecting plate is provided on the hub, and a plurality of rivet holes are evenly distributed along the circumference of the connecting plate; an arc-shaped connecting hole corresponding to the connecting hole is provided on the magnetic steel rotor, and the magnetic steel rotor is installed on the connecting plate with an adjustable angle through rivets.

3. The ignition timing structure of a two-stroke multi-cylinder aircraft engine as claimed in claim 2, characterized in that: An external spline is arranged on the output shaft of the crankshaft, an internal spline is arranged in the propeller hub, and the propeller hub is installed on the output shaft of the crankshaft through a spline structure.

4. The ignition timing structure of a two-stroke multi-cylinder aircraft engine according to claim 1, characterized in that: A fixing plate is installed on the crankcase of the aircraft engine, and a plurality of threaded holes are arranged on the fixing plate; a plurality of long strip holes are arranged on the silicon steel sheet, and a pair of magnetic electrodes are adjustably mounted on the fixing plate through bolts.

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