Scavenging plug capable of improving power of two-stroke small gasoline engine

Abstract

The utility model belongs to the technical field of engines, and relates to a scavenging plug capable of improving the power of a two-stroke small gasoline engine, the scavenging plug is embedded in an air outlet of a crankcase and comprises a plug body, a left cantilever and a right cantilever, the left cantilever and the right cantilever are arranged on the two sides of the plug body, and the plug body abuts against the upper end face and the lower end face of the air outlet. The left cantilever and the right cantilever abut against the left end face and the right end face of the air outlet respectively, and the plug body divides the air outlet into a left channel and a right channel which correspond to the left scavenging duct and the right scavenging duct respectively. According to the scavenging plug capable of improving the power of the two-stroke small gasoline engine, the internal volume of a crankcase can be reduced, the working power can be improved, and a scavenging channel can be smoother.

Description

Technical Field

[0001] The utility model belongs to the technical field of engines and relates to a scavenging plug which can improve the power of a small two-stroke gasoline engine. Background Art

[0002] A two-stroke small gasoline engine is different from a four-stroke gasoline engine. Its crankshaft scavenges the cylinder air intake every time it rotates one circle, so the cylinder burns and does work every time the crankshaft rotates one circle.

[0003] Due to the limitation of processing technology, most two-stroke small gasoline engines have a lot of extra space inside the crankcase. The existence of this space is meaningless to the rotation of the crankshaft. However, the existence of extra space will affect the power of the two-stroke small gasoline engine: 1. This extra space will weaken the scavenging efficiency of the crankcase, resulting in limited combustible mixture provided to the cylinder for each stroke of the crankshaft, and it is difficult to increase the engine power. 2. It will cause the combustible mixture to form turbulence before being squeezed into the cylinder scavenging passage (just like the extra space temporarily "retains" the combustible mixture that should have entered the cylinder immediately), and the airflow cannot be efficiently introduced into the cylinder. Utility Model Content

[0004] The utility model aims at the deficiencies of the prior art and provides a scavenging plug which can improve the power of a two-stroke small gasoline engine, can reduce the internal volume of a crankcase, improve the working power, and can make the scavenging passage smoother.

[0005] In order to solve the above technical problems, the purpose of the utility model is achieved through the following technical solutions:

[0006] A scavenging plug capable of improving the power of a small two-stroke gasoline engine, the scavenging plug being embedded in the air outlet of a crankcase, comprising a plug body and a left cantilever and a right cantilever arranged on both sides of the plug body, the plug body abutting against the upper and lower end surfaces of the air outlet, the left cantilever and the right cantilever respectively abutting against the left and right end surfaces of the air outlet, and the plug body dividing the air outlet into a left channel and a right channel corresponding to a left scavenging passage and a right scavenging passage respectively.

[0007] In the above-mentioned scavenging plug capable of improving the power of a two-stroke small gasoline engine, the scavenging plug is made of elastic material, and the plug body, the left cantilever and the right cantilever are interference fit with the air outlet through their elastic deformation. Further, the scavenging plug is preferably made of a material with slight compressive elasticity.

[0008] In the above-mentioned scavenging plug capable of improving the power of a small two-stroke gasoline engine, preferably, the scavenging plug is made of nylon PA6, and the plug body, the left cantilever and the right cantilever are integrally injection molded.

[0009] In the above-mentioned scavenging plug capable of improving the power of a two-stroke small gasoline engine, the cross-sectional areas of the left channel and the right channel are adapted to the minimum cross-sectional areas of the left scavenging passage and the right scavenging passage of the cylinder. In the present utility model, the cross-sectional areas of the left channel and the right channel are adapted to the minimum cross-sectional areas of the left scavenging passage and the right scavenging passage of the cylinder, which means that the cross-sectional areas of the left channel and the right channel will not form an "airflow bottleneck" of the left scavenging passage and the right scavenging passage. Generally speaking, the cross-sectional areas of the left channel and the right channel are equivalent to or slightly larger than the minimum cross-sectional areas of the left scavenging passage and the right scavenging passage of the cylinder.

[0010] In the above-mentioned scavenging plug capable of improving the power of a two-stroke small gasoline engine, the crankcase includes a left crankcase and a right crankcase, the scavenging plug is arranged symmetrically on the left and right sides, and the outer contour of the plug body is adapted to the contour of the interface between the left crankcase and the right crankcase. In the present utility model, the outer contour of the plug body is adapted to the contour of the interface between the left crankcase and the right crankcase, which means that the outer contour of the plug body is equivalent to or has a small interference with the contour of the interface between the left crankcase and the right crankcase.

[0011] In the above-mentioned scavenging plug capable of improving the power of a small two-stroke gasoline engine, the ratio of the width of the plug body to the width of the air outlet is 1:4-1:3.

[0012] In the above-mentioned scavenging plug capable of improving the power of a small two-stroke gasoline engine, a circular arc transition angle (R angle) is provided at the connection between the left cantilever, the right cantilever and the plug body.

[0013] In the above-mentioned scavenging plug capable of improving the power of a small two-stroke gasoline engine, the left cantilever and the right cantilever are connected to the middle of the front end of the plug body, and the cross-section of the left cantilever and the right cantilever is elliptical, and the long axis thereof is arranged along the flow direction of the gas.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The utility model provides a scavenging plug that can improve the power of a two-stroke small gasoline engine. By arranging a scavenging plug at the outlet of the crankcase, the originally spacious outlet of the crankcase is divided into two left and right channels, which can reduce the volume of the crankcase, improve the scavenging efficiency of the crankcase, and directly increase the intake volume of each stroke of the cylinder combustion chamber, thereby improving the power of the engine. At the same time, the two channels of the utility model correspond to two scavenging passages, respectively, further ensuring the smoothness of the scavenging passage and preventing the combustible mixed gas from forming turbulence. Therefore, the scavenging plug of the two-stroke small gasoline engine power provided by the utility model can reduce the internal volume of the crankcase, improve the working power, and make the scavenging passage smoother. Moreover, the scavenging plug of the utility model has a simple structure and does not require accessories during installation, which is very convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a three-dimensional diagram of the utility model;

[0017] Figure 2 It is a cross-sectional view of the utility model;

[0018] Figure 3 It is a three-dimensional diagram of the scavenging plug of the utility model;

[0019] Figure 4 This is a front view of the scavenging plug of the utility model;

[0020] Figure 5 It is a side view of the scavenging plug of the utility model;

[0021] Figure numerals: 1. scavenging plug; 11. plug body; 12. left cantilever; 13. right cantilever; 14. arc transition angle; 2. crankcase; 21. air outlet; 22. left channel; 23. right channel; 24. left crankcase; 25. right crankcase; 3. cylinder; 31. left scavenging duct; 32. right scavenging duct. DETAILED DESCRIPTION

[0022] The present invention will be further described below with reference to the accompanying drawings. Figure 1-5 :

[0023] A scavenging plug 1 capable of improving the power of a two-stroke small gasoline engine, the scavenging plug 1 is embedded in an air outlet 21 of a crankcase 2, and comprises a plug body 11 and a left cantilever 12 and a right cantilever 13 arranged on both sides of the plug body 11, the plug body 11 abuts against the upper and lower end surfaces of the air outlet 21, the left cantilever 12 and the right cantilever 13 respectively abut against the left and right end surfaces of the air outlet 21, and the plug body 11 divides the air outlet 21 into a left channel 22 and a right channel 23 corresponding to a left scavenging passage 31 and a right scavenging passage 32 respectively.

[0024] Compare with Figure 1 During operation, the crankshaft of the crankcase 2 rotates to squeeze the air into the cylinder 3 to scavenge the air. The combustible mixture is divided into two air flows by the scavenge plug 1, and enters the left scavenge passage 31 and the right scavenge passage 32 of the crankcase 2 through the left channel 22 and the right channel 23 respectively, and then enters the left scavenge passage 31 and the right scavenge passage 32 of the cylinder 3 to complete the scavenging.

[0025] The scavenging plug 1 is made of elastic material, and the plug body 11, the left cantilever 12 and the right cantilever 13 are interference fit with the gas outlet 21 through their elastic deformation. Further, the scavenging plug 1 is preferably made of a material with slight compression elasticity.

[0026] In this embodiment, the scavenging plug 1 is made of nylon PA6, and the plug body 11, the left cantilever 12 and the right cantilever 13 are integrally injection molded. The scavenging plug 1 made of nylon PA6 has good strength and toughness, and has slight compression elasticity, and can be well pressed into and encapsulated inside the crankcase 2.

[0027] The cross-sectional areas of the left channel 22 and the right channel 23 are adapted to the minimum cross-sectional areas of the left scavenging passage 31 and the right scavenging passage 32 of the cylinder 3. In the present embodiment, the cross-sectional areas of the left channel 22 and the right channel 23 are slightly larger than the minimum cross-sectional areas of the left scavenging passage 31 and the right scavenging passage 32 of the cylinder 3. By limiting the cross-sectional areas of the left channel 22 and the right channel 23, the "airflow bottleneck" is avoided in the channel. Of course, the channel cannot be designed too large, otherwise it will not play a role in improving the scavenging efficiency. Therefore, the cross-sectional areas of the left channel 22 and the right channel 23 need to be adapted to the minimum cross-sectional areas of the left scavenging passage 31 and the right scavenging passage 32 of the cylinder 3.

[0028] Compare with Figure 2 The crankcase 2 includes a left crankcase 24 and a right crankcase 25, the scavenging plug 1 is symmetrically arranged, and the outer contour of the plug body 11 is adapted to the contour of the interface between the left crankcase 24 and the right crankcase 25. Specifically, the outer contour of the plug body 11 is equivalent to the contour of the interface between the left crankcase 24 and the right crankcase 25, or there may be a small interference, and the plug body 11 is extruded and assembled during installation.

[0029] Compare with Figure 4 In this embodiment, the width of the plug body 11 needs to be moderate. If it is too wide, the cross-sectional area of ​​the left and right scavenging ports will be reduced, hindering the air intake. If it is too narrow, not only the reliability of the accessories is poor and easy to loosen, but it also does not help much in reducing the volume of the crankcase 2, and the improvement of the scavenging efficiency is also general. Taking all factors into consideration, the ratio of the width of the plug body 11 to the width of the outlet port 21 is 1:4-1:3.

[0030] Compare with Figure 3 A circular arc transition angle 14 (R angle) is provided at the connection between the left cantilever 12, the right cantilever 13 and the plug body 11. By setting a larger R angle, it can be ensured that the cantilever is not easy to break.

[0031] Compare with Figure 4 The left cantilever 12 and the right cantilever 13 are connected to the middle of the front end of the plug body 11. The cross-section of the left cantilever 12 and the right cantilever 13 is elliptical, and the long axis thereof is arranged along the flow direction of the gas. In addition, the cross-sectional area of ​​the cantilever should also be moderate. The cross-sectional area of ​​the cantilever should not be too large, which will hinder the combustible mixture from entering the cylinder 3, nor should it be too small, which will easily break and be unreliable to install.

[0032] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A scavenging plug capable of increasing the power of a small two-stroke gasoline engine, characterized in that: The scavenging plug (1) is embedded in the air outlet (21) of the crankcase (2), and comprises a plug body (11) and a left cantilever (12) and a right cantilever (13) arranged on both sides of the plug body (11); the plug body (11) abuts against the upper and lower end surfaces of the air outlet (21); the left cantilever (12) and the right cantilever (13) respectively abut against the left and right end surfaces of the air outlet (21); the plug body (11) divides the air outlet (21) into a left channel (22) and a right channel (23) corresponding to the left scavenging passage (31) and the right scavenging passage (32), respectively.

2. A scavenging plug capable of improving the power of a two-stroke small gasoline engine according to claim 1, characterized in that: The scavenging plug (1) is made of elastic material, and the plug body (11), the left cantilever (12) and the right cantilever (13) are interference-fitted with the air outlet (21) through their elastic deformation.

3. A scavenging plug capable of improving the power of a two-stroke small gasoline engine according to claim 2, characterized in that: The scavenging plug (1) is made of nylon PA6, and the plug body (11), the left cantilever (12) and the right cantilever (13) are integrally injection-molded.

4. A scavenging plug capable of improving the power of a two-stroke small gasoline engine according to claim 1, characterized in that: The cross-sectional areas of the left channel (22) and the right channel (23) are adapted to the minimum cross-sectional areas of the left scavenging channel (31) and the right scavenging channel (32) of the cylinder (3).

5. A scavenging plug capable of improving the power of a small two-stroke gasoline engine according to claim 1, characterized in that: The crankcase (2) comprises a left crankcase (24) and a right crankcase (25), the scavenging plug (1) is arranged symmetrically on the left and right sides, and the outer contour of the plug body (11) is adapted to the contour of the interface between the left crankcase (24) and the right crankcase (25).

6. A scavenging plug capable of improving the power of a small two-stroke gasoline engine according to claim 1, characterized in that: The ratio of the width of the plug body (11) to the width of the air outlet (21) is 1:4-1:

3.

7. A scavenging plug capable of improving the power of a two-stroke small gasoline engine according to claim 1, characterized in that: The connection between the left cantilever (12), the right cantilever (13) and the plug body (11) is provided with an arc transition angle (14).

8. A scavenging plug capable of improving the power of a two-stroke small gasoline engine according to claim 1, characterized in that: The left cantilever (12) and the right cantilever (13) are connected to the middle of the front end of the plug body (11); the cross-sections of the left cantilever (12) and the right cantilever (13) are elliptical, and their major axes are arranged along the flow direction of the gas.

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