TWI729166B - Cylinder structure of internal combustion engine - Google Patents

Abstract

A cylinder structure of an internal combustion engine includes a cylinder body and two side covers. The cylinder body is die-casting and has a combustion chamber surrounded by an outer ring wall and a cylinder head, and an air inlet located on both sides of the combustion chamber And an exhaust port and two scavenging units arranged alternately with the intake port and the exhaust port. The scavenging unit has a first scavenging port and a second scavenging port. The exhaust port is adjacent to the combustion chamber and has a high height At the air inlet, the height position of the first scavenging port and the second scavenging port are defined between the air inlet and the air outlet. The side covers are respectively covered on the outside of the scavenging unit to close the scavenging port, and a scavenging air channel is formed between the outer ring wall and the outer ring wall. When the scavenging operation is performed, the exhaust gas is brought in from the first scavenging port and passes through the scavenging air. The passage is then discharged from the second scavenging port toward the exhaust port.

Description

Cylinder structure of internal combustion engine

This creation is about a kind of cylinder, especially a kind of cylinder structure for manufacturing a simple and fast internal combustion engine.

As shown in Figure 7, it is an existing two-stroke internal combustion engine, which includes a cylinder 1, a crankcase 2 located at the bottom of the cylinder 1, a piston 3 located inside the cylinder 1, and a crankshaft located inside the crankcase 2. 201. A connecting rod 4 connected between the crankshaft 201 and the piston 3, and a spark plug 5 arranged at the top of the cylinder 1, the cylinder 1 having a combustion chamber 6 located inside, and located on the side wall of the cylinder 1 body An air intake 7, an exhaust 8 and a scavenging port 9. After the internal combustion engine is in the gas exchange phase, it will enter the scavenging phase. At this time, the crankshaft 201 drives the connecting rod 4 to displace the piston 3 downward to open the scavenging port 9. At this time, the exhaust gas is pushed in and passed through the scavenging port 9 The exhaust port 8 is discharged to the outside to complete the scavenging operation.

Since the internal combustion engine must have scavenging operation to remove the exhaust gas trapped in the crankcase, the arrangement of the intake port, exhaust port, and scavenging port is the most difficult in the production of cylinders. Moreover, the conventional cylinder In order to meet the need of scavenging efficiency, the scavenging port is designed to be a winding and complex structure inside the body, which makes it impossible to directly cut and shape with processing tools. Because of this, the previous cylinders are cast in sand casting (or gravity casting). ), in order to obtain castings with the above-mentioned structure, a special manufacturing method of precision dewaxing must be used to form a scavenging port structure integrally formed with the cylinder body. However, this method is only suitable for small batch production, which also leads to the failure of the cylinder The production speed is slow, the output is small, it is not economical, and the relative manufacturing cost is also increased, which is bound to be passed on to consumers, which is not conducive to maintaining product competitiveness.

The cylinder structure of the internal combustion engine in this creation is formed by directly forming a hollow scavenging port on the cylinder body during die-casting, and the side cover is used to cover the scavenging port on the outside of the cylinder body to form a serpentine scavenging port. Air flow channel to achieve the advantages of rapid manufacturing and increased output.

The cylinder structure of the internal combustion engine created by this invention is made by die-casting, which is easy to manufacture and low in cost, and overcomes the problems of slow process speed and high cost caused by the dewaxing of the cylinder body in the past.

In addition, for the cylinder structure of the internal combustion engine of the present invention, the cylinder head can be made by integral molding combined with the cylinder body. In addition, it can also be combined separately after die-casting, which has the advantages of easy and fast manufacturing.

Therefore, the cylinder structure of an internal combustion engine proposed in this creation includes a cylinder body and two side covers. The cylinder body is die-casting and has a combustion chamber surrounded by an outer ring wall and a cylinder head, an intake port and an exhaust port located on both sides of the combustion chamber, and a side edge of the combustion chamber And there are two scavenging units arranged alternately with the air intake and exhaust ports. The scavenging unit has a first scavenging port and a second scavenging port. The exhaust port is adjacent to the combustion chamber and is higher than the height of the scavenging unit. The air inlet, the height position of the first scavenging port and the second scavenging port of the aforementioned scavenging unit is bounded between the air inlet and the air outlet. The side covers are respectively covered on the outside of the scavenging unit to close the first scavenging port and the second scavenging port, and a scavenging air passage is formed between the side cover and the outer ring wall. When the internal combustion engine performs scavenging operation, the exhaust gas It is brought in from the first scavenging port, passing through the scavenging air passage, and then discharged from the second scavenging port toward the exhaust port.

According to the above-mentioned cylinder structure of the internal combustion engine according to the present invention, the scavenging unit further has an open groove and a rib transversely connected to the middle section of the open groove, and the first rib is formed between the two sides of the rib and the open groove. For the scavenging port and the second scavenging port, the thickness of the rib is smaller than the groove depth of the open groove, and the inner side of the rib is flush with an inner peripheral wall of the combustion chamber.

According to the above-mentioned cylinder structure of the internal combustion engine according to the present invention, the first scavenging port is adjacent to the bottom of the cylinder body and the height is not lower than the intake port, and the second scavenging port is adjacent to the combustion chamber and has a high height. At the air inlet, lower than the air outlet.

According to the above-mentioned cylinder structure of the internal combustion engine of the present invention, each side cover has a first embedding portion provided on the edge of the cover, and the cylinder body further has two second embedding portions provided on the outside of the scavenging units Part, the first embedding part of the side cover corresponds to the second embedding part, and is fixed by an airtight material, so that the side cover is combined with the cylinder body.

According to the above-mentioned cylinder structure of the internal combustion engine in this creation, the airtight material is anaerobic curing acrylate.

According to the above-mentioned cylinder structure of the internal combustion engine according to the present invention, the first engaging portion of the side cover is a convex portion, and the second engaging portion of the cylinder body is a concave portion.

According to the above-mentioned cylinder structure of the internal combustion engine in this creation, the cylinder body further has a plurality of radiating fins arranged on an outer peripheral wall.

According to the above-mentioned cylinder structure of the internal combustion engine in this creation, the cylinder body is made of aluminum die-casting.

According to the above-mentioned cylinder structure of the internal combustion engine in this creation, the aforementioned side cover is made of aluminum die-casting.

According to the above-mentioned cylinder structure of the internal combustion engine in this creation, a spark plug inlet and a throttle inlet are further provided on the cylinder head of the cylinder body.

According to the above-mentioned cylinder structure of the internal combustion engine according to the present invention, the cylinder head of the cylinder body is integrally formed and joined to the top of the cylinder body.

According to the above, compared with the existing internal combustion engine cylinders must be matched with the dewaxing manufacturing method, the scavenging ports can be made on the cylinder body, so the production is slow and the output is low. The cylinder structure of the internal combustion engine in this creation is formed by die-casting. In this way, a hollow scavenging port is directly formed on the cylinder body, and then the side cover is embedded on the outside of the scavenging port, and the scavenging air passage formed in the cylinder body allows the internal combustion engine to perform scavenging operations and overcomes In the past, the cylinder body was difficult to manufacture and other problems. Therefore, the cylinder structure of the internal combustion engine of the invention not only has the advantages of easy and fast manufacturing, but also has a relatively higher output, so it has the advantages and effects of reducing manufacturing costs.

100‧‧‧Cylinder

10‧‧‧Cylinder body

11‧‧‧Outer Ring Wall

111‧‧‧Combustion chamber

112‧‧‧Inner wall

113‧‧‧peripheral wall

12‧‧‧Air inlet

13‧‧‧Exhaust port

14‧‧‧Second embedding part

15‧‧‧Heat sink

20‧‧‧Cylinder head

21‧‧‧ Spark plug entrance

22‧‧‧Throttle valve inlet

30‧‧‧Side cover

31‧‧‧The first embedding part

40‧‧‧Scavenge unit

41‧‧‧First scavenging port

42‧‧‧Second scavenging port

43‧‧‧Open slot

44‧‧‧ Ribs

441‧‧‧Inside

45‧‧‧Sweeping air duct

50‧‧‧Piston

60‧‧‧Crankcase

61‧‧‧Crankshaft

62‧‧‧Connecting rod

200‧‧‧Cylinder

W1‧‧‧Thickness

W2‧‧‧Groove depth

Figure 1 is a perspective view of a preferred embodiment of the cylinder structure of an internal combustion engine.

Figure 2 is a perspective view of the cylinder structure of the internal combustion engine.

Figure 3 is a side view of the cylinder structure of the internal combustion engine.

Figure 4 is a cross-sectional view of the cylinder structure of the internal combustion engine.

Figure 5 is another cross-sectional view of the cylinder structure of the internal combustion engine.

Figure 6 is a combined cross-sectional view of the cylinder head and the cylinder body in a two-stage structure.

Figure 7 is a schematic diagram of the combination of a conventional two-stroke internal combustion engine.

In a preferred embodiment of the cylinder structure of the internal combustion engine of the invention, the cylinder 100 is provided with a piston 50, the bottom of the cylinder 100 is connected to a crankcase 60, and the crankcase 60 is provided with a crankshaft 61 and a crankshaft 61 and The connecting rod 62 between the pistons 50 drives the piston 50 to perform up and down displacement actions, as shown in FIG. 4.

As shown in FIGS. 1 to 4, the cylinder 100 of this invention includes a cylinder body 10, a cylinder head 20, and two side covers 30. The cylinder body 10 is made of aluminum die-casting and has a combustion chamber 111 (see Figure 5) surrounded by an outer ring wall 11 and the cylinder head 20, and a combustion chamber 111 on both sides of the combustion chamber 111. The intake port 12 and an exhaust port 13, and a second scavenging unit 40 located on the side of the combustion chamber 111 and alternately arranged with the intake port 12 and the exhaust port 13. The aforementioned scavenging unit 40 has a first scavenging unit 40 The air port 41 and a second scavenging port 42, the exhaust port 13 is adjacent to the combustion chamber 111 and is higher than the intake port 12. The height of the first scavenging port 41 and the second scavenging port 42 of the aforementioned scavenging unit 40 The location is between the air inlet 12 and the air outlet 13. In addition, the aforementioned scavenging unit 40 further has an open groove 43 and a rib 44 transversely connected to the middle section of the open groove 43. The first scavenging port 41 and the rib 44 are formed between both sides of the rib 44 and the open groove 43. For the second scavenging port 42, the thickness W1 of the rib 44 is less than the depth W2 of the open groove 43, and the inner side 441 of the rib 44 is flush with an inner peripheral wall 112 of the combustion chamber 111 (as shown in Figures 2 and 5) Shown).

Referring to Figures 1 and 5, the aforementioned side cover 30 presents an outwardly convex bulge, and is respectively covered on the outside of each scavenging unit 40 to close the first scavenging port 41 and the second scavenging port 42, and to A scavenging air passage 45 that is roughly inverted U-shaped is formed between the outer ring walls 11. When the internal combustion engine performs scavenging operations, exhaust gas is brought in from the first scavenging port 41, and then passes through the scavenging air passage 43 from the second scavenging port. 42 is discharged toward the exhaust port 13 outward. In this embodiment, each side cover 30 has a first embedding portion 31 provided on the edge of the cover, and the cylinder body 10 further has two second embedding portions 14 provided on the outside of the scavenging units 40, The first embedding portion 31 of the side cover 30 corresponds to the second embedding portion 14 and is fixed by an airtight material 32 so that the side cover 30 is bonded to the cylinder body 10. In this case, the airtight material 32 is anaerobic curing acrylate. In FIG. 5, the first engaging portion 31 of the side cover 30 is a convex portion, and the second engaging portion 14 of the cylinder body 10 is a concave portion.

It is worth mentioning that, as shown in Figures 1 and 5, the cylinder body 10 further has a plurality of radiating fins 15 arranged on an outer peripheral wall 113 to both perform heat dissipation.

Further, the first scavenging port 41 of the scavenging unit 40 is adjacent to the bottom of the cylinder body 10, and the height is not lower than the intake port 12. The aforementioned second scavenging port 42 is adjacent to the combustion chamber 111, and The height is higher than the intake port 12 and lower than the exhaust port 13.

Secondly, the cylinder head 20 is further provided with a spark plug inlet 21 and a throttle valve inlet 22 for installing a spark plug and a throttle valve respectively (not shown in the figure). In Figures 1 and 4, the cylinder head 20 is integrally formed on the top of the cylinder body 10 by die-casting, so as to achieve simple and rapid manufacturing. In addition, as shown in Figure 6, the cylinder body 10 and the cylinder head 20 of the cylinder 200 are made of aluminum die-casting respectively, and then the cylinder head 20 is bonded to the top of the cylinder body 10 by airtight material. Therefore, it is easy to manufacture and quick to manufacture.

As mentioned above, compared with the existing internal combustion engine cylinders, the dewaxing manufacturing method must be used to make the scavenging ports on the cylinder body, resulting in slow manufacturing and low output. The cylinder structure of the internal combustion engine in this creation is formed by die-casting. , A hollow scavenging port (that is, the aforementioned first scavenging port 41, second scavenging port 42) is directly formed on the cylinder body 10, and then the side cover 30 is used to insert and cover the outer side of the scavenging port, so that the cylinder body 10 The outer surface is airtight, and the scavenging air passage 45 formed in the cylinder body 10 by the cooperation of the inner groove of the side cover 30 and the scavenging port allows the internal combustion engine to perform scavenging operations. Therefore, the scavenging air passage in this creation 45 does not need to be made by dewaxing method, and overcomes the problems of difficult manufacturing of the cylinder body in the past.

Therefore, the cylinder structure of the internal combustion engine in this invention is used to manufacture the cylinder body 10 and the side cover 30 separately by die casting, and then fix the side cover 30 with the gluing method. It is not only easy and fast to manufacture, but also the output can be relatively improved, so it has both The advantages and effects of reducing manufacturing costs. Secondly, since each side cover 30 is formed with an outward convex bulge, a relatively wide scavenging air passage 45 is naturally formed between the bulging structure and the first scavenging port 41 and the second scavenging port 42 to enlarge the flow passage space. , And then provide the smoothness of the scavenging operation and improve the scavenging efficiency.

In addition, since the operation process of the internal combustion engine is not the focus of this case, it is not explained in detail in this creation, and its operation mode is the same as that of the previous internal combustion engine, so I will not repeat it.

The above is only a preferred embodiment of this creation, and should not be used to limit the scope of implementation of this creation, that is to say, all simple equivalent changes and modifications made according to the scope of patent application and implementation methods of this creation are all Should still be within the scope of this creation patent.

100‧‧‧Cylinder

10‧‧‧Cylinder body

11‧‧‧Outer Ring Wall

12‧‧‧Air inlet

13‧‧‧Exhaust port

14‧‧‧Second embedding part

15‧‧‧Heat sink

20‧‧‧Cylinder head

21‧‧‧ Spark plug entrance

30‧‧‧Side cover

31‧‧‧The first embedding part

40‧‧‧Scavenge unit

41‧‧‧First scavenging port

42‧‧‧Second scavenging port

43‧‧‧Open slot

44‧‧‧ Ribs

Claims (10)

A cylinder structure of an internal combustion engine, including: a cylinder body, which is die-casted, has a combustion chamber surrounded by an outer ring wall and a cylinder head, an intake port and an exhaust located on both sides of the combustion chamber And two scavenging units located on the side of the combustion chamber and alternately arranged with the intake and exhaust ports. The scavenging unit has a first scavenging port and a second scavenging port, and the exhaust port is adjacent to In the combustion chamber and the height is higher than the intake port, the first scavenging port and the second scavenging port of the scavenging unit are located between the intake port and the exhaust port. The scavenging unit further has a An open groove, a rib transversely connected to the middle section of the open groove, the first scavenging port and the second scavenging port are formed between the two sides of the rib and the open groove, and the thickness of the rib is smaller than the groove depth of the open groove , And the inner side of the rib is flush with an inner peripheral wall of the combustion chamber; and two side covers are respectively covered on the outer side of the scavenging unit to close the first scavenging port and the second scavenging port, and A scavenging air passage is formed between the outer ring walls. When the internal combustion engine performs scavenging operation, exhaust gas is taken in from the first scavenging port, and then discharged from the second scavenging port toward the exhaust port through the scavenging air passage. The cylinder structure of an internal combustion engine according to claim 1, wherein the first scavenging port is adjacent to the bottom of the cylinder body and the height is not lower than the intake port, and the second scavenging port is adjacent to the combustion chamber , And the height is higher than the intake port and lower than the exhaust port. The cylinder structure of an internal combustion engine according to claim 1, wherein each of the side covers has a first engagement portion provided on the edge of the cover, and the cylinder body further has two outer sides of the scavenging units The second embedding portion corresponds to the second embedding portion of the side cover and is fixed by an airtight material so that the side cover is combined with the cylinder body. The cylinder structure of an internal combustion engine according to claim 3, wherein the airtight material is anaerobic curing acrylate. The cylinder structure of an internal combustion engine according to claim 3, wherein the first engagement portion of the side cover is The convex part, the second embedding part of the cylinder body is a concave part. The cylinder structure of an internal combustion engine according to claim 1, wherein the cylinder body further has a plurality of radiating fins arranged on an outer peripheral wall. The cylinder structure of an internal combustion engine according to claim 1, wherein the cylinder body is made of aluminum die-casting. The cylinder structure of an internal combustion engine according to claim 1, wherein the side cover is made of aluminum die-casting. The cylinder structure of an internal combustion engine according to claim 1, wherein the cylinder head of the cylinder body is further provided with a spark plug inlet and a throttle valve inlet. The cylinder structure of the internal combustion engine according to claim 1, wherein the cylinder head of the cylinder body is integrally formed and joined to the top of the cylinder body.

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