JPH02301607A - Rotary sleeve valve internal combustion engine - Google Patents

Abstract

PURPOSE:To improve efficiency in exhaust cycles by inserting an upper piston which has a spring opposing to a piston connected to a crank shaft into an upper pert of a rotary cylinder valve. CONSTITUTION:A rotary cylinder valve 3 which is rotated by means of a crank shaft 20 is inserted into a cylinder block 1. An intake port 10 and a discharge port arranged on the cylinder block 1 are agreed with an opening 5 formed on the rotary cylinder valve 3 synchronously to engine cycle. A piston 32 con nected to the crank shaft 20 and an upper piston 50 opposing thereto and having a coil spring thereinside are inserted into the rotary cylinder valve 3. In an exhaust cycle, the upper piston 50 is pressed back by the coil spring 60. Gap between the lifting piston 3 and the upper piston 50 is remarkably reduced, so that exhaust gas is discharged from the opening 5 almost completely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to internal combustion engines. More specifically, the present invention relates to a type of rotary sleeve valve internal combustion engine having a rotary sleeve valve mechanism for intake and exhaust of fuel, in which pistons are disposed opposite each other in order to improve exhaust efficiency.

[Prior Art] In an internal combustion engine with a reciprocating piston, a mixed gas of fuel and air is sucked into a cylinder chamber through an intake valve, and after explosive combustion occurs in the cylinder chamber, the combustion gas is discharged through an exhaust valve. Valve mechanisms for supplying and exhausting air are roughly classified into three types: mushroom valve mechanisms, sleeve valve mechanisms, and rotary valve mechanisms. Mushroom valve mechanisms are widely used in internal combustion engines and usually consist of a valve device and a drive device. A valve device includes a cam that controls the opening and closing of the valve, a transmission mechanism that transmits the movement of the cam, and an opening and closing mechanism that converts the movement of the valve into the opening and closing movement of the valve. This drive device is a mechanism that drives the camshaft in synchronization with the rotation of the crankshaft.

The mushroom valve devices currently in use are based on engine performance characteristics,
Several types of mechanisms are used commercially, depending on combustion chamber shape, serviceability, manufacturing cost, etc. They are broadly divided into the side valve type, which is mainly used in general-purpose engines, and the overhead valve type, which is used in automobile engines. Further, drive devices include gear drive, chain drive, and toothed belt drive.

In the sleeve valve mechanism, a sleeve is fitted onto the inner surface of a cylinder, and the sleeve is moved up and down or rotated to open and close intake and exhaust ports.

A rotary valve is a mechanism in which a rotor is provided in a part of an intake/exhaust passage or a combustion chamber, and the rotor is rotated to communicate with an intake/exhaust port. A rotary sleeve valve among sleeve valves opens and closes the intake and exhaust ports by rotating the sleeve.
It is described in Publication No. 5704, etc. These valves using sleeve valves have the following advantages: they have a large valve hole area, so they have good ventilation efficiency for intake and exhaust, the valve mechanism is relatively simple, and there is little noise. Due to the difficulty of maintaining airtightness between the cylinder block and the cylinder block, the difficulty of lubricating the rotating contact surfaces, and friction loss, it is currently not put into practical use except for special purposes.

[Problem to be solved by the invention] The sleeve valve type internal combustion engine described above is a past technology, and the sealing technology at the time of development was insufficient to prevent gas leakage and lubrication technology, making it impossible to increase the compression ratio very much. There was a problem. In addition, sleeve valve internal combustion engines
It is known to have good exhaust efficiency. However, it is not possible to completely exhaust exhaust gas.

An object of the present invention is to provide a structure for a rotary sleeve valve internal combustion engine that improves exhaust efficiency.

Still another object of the present invention is to provide an opposed piston type rotary sleeve valve internal combustion engine in which the sealing effect of the rotary sleeve valve is improved. .

[Means for solving the above problems] In order to solve the above problem, the following measures are taken.

The first means is a sleeve valve internal combustion engine consisting of a cylinder block, a rotary cylinder valve, two opposing pistons, a crankshaft, etc.; a. The cylinder block takes in and discharges mixed gas and exhaust gas; b. The rotary cylinder valve is rotatably supported within the cylinder block and has a cylindrical space at the center, and the rotary cylinder valve has an opening; and d. a gear is provided at one end of the rotary cylinder valve; e. the two pistons are slidably inserted into the rotary cylinder valve facing each other across the opening; and f. one of the pistons. a crankshaft connected to the piston and rotatably provided on the connecting rod; g) the other piston is movably opposed to the one piston with a spring interposed therebetween; h) the crankshaft is provided on the crankshaft; A rotary sleeve valve internal combustion engine comprising a crank gear that meshes with the gear.

A seal ring may be disposed annularly around the opening to seal the suction hole and the exhaust hole.

The other piston may be fixed to the cylinder block so as to allow movement only in the axial direction of the rotary cylinder valve.

The other piston may be fixed to the rotary cylinder valve so as to allow movement of the rotary cylinder valve in an axial direction.

It is preferable that the other piston cannot move beyond a certain distance against the spring.

Furthermore, a water pump or fins may be provided on the outer periphery of the rotary cylinder valve.

[Operation] The starter rotates the crankshaft. When the piston moves toward the bottom dead center, that is, when it moves away from the upper piston, the opening of the rotary cylinder valve coincides with the suction hole, and the mixed gas is sucked through this opening.

At this time, since the crank gear of the crankshaft is driving one end of the rotary cylinder valve, the timing is adjusted so that the opening and the suction hole coincide. The piston moves toward top dead center again, ie approaches the upper piston and compresses the mixed gas.

At this time, the upper piston is slightly moved back by the gas pressure of the compressed gas, compressing the spring.

Immediately before the piston reaches top dead center, the ignition plug ignites the compressed gas mixture, causing it to combust and expand after the piston reaches top dead center. The piston is pushed by the combustion gas and moves, driving the crankshaft. At the same time, the upper piston moves back due to the explosive force, but then returns to its original position. The piston rises again, the opening communicates with the exhaust hole, and exhaust gas is exhausted from the exhaust hole to the outside of the engine. Since there is almost no gap between the piston and the upper piston, most of the exhaust gas is exhausted. Repeat this operation thereafter.

[First example] Embodiments of the present invention will be described below with reference to the drawings.

What is shown in FIG. 1 is an embodiment in which a rotary cylinder valve is provided. The cylinder block 1 is a cylindrical case with a hollow interior, and is made of a casting material that is a common engine material. A crankcase 2 is provided at the lower end of the cylinder block 1. The crankcase 2 has a built-in crankshaft 20. A cylindrical rotary cylinder valve 3 is rotatably inserted into the cylinder block 1.

A bevel gear 4 is integrally connected to one end of the rotary cylinder valve 3. The bevel gear 4 may be made separately from the rotary cylinder valve 3 and then assembled after gear cutting.The rotary cylinder valve 3 has an opening in the center that is oval when viewed from the inside and has a circular outlet. A plurality of blades 6 are integrally provided in the radial direction on the outer periphery of the rotary cylinder valve 3 (Fig. 2).
The vanes 6 correspond to the vanes of a pump for circulating cooling water, and have a lead angle with respect to the rotational axis of the rotary cylinder valve 3.

The cylinder block 1 is provided with an intake hole 10 and an exhaust hole. The opening positions of the suction hole 10 and the exhaust hole are arranged in synchronization with the movement of the opening 5 to match the suction, compression, expansion, and exhaust cycles of the engine. A cavity is formed between the rotary cylinder valve 3 and the cylinder block 1, and this cavity is a cooling chamber 8 for cooling the rotary cylinder valve 3. This cooling chamber 8 is filled with cooling water to cool the outer periphery of the rotary cylinder valve 3.

Further, both ends of the rotary cylinder valve 3 are rotatably supported by bearings. For the bearing, choose a material that is heat resistant and corrosion resistant, and use a bearing that can withstand loads in the thrust direction. The crankshaft 20 has arm portions 22.22 at both ends with a bottle 21 in the center thereof, and the arm portion 22 further has a journal portion 23 eccentric to the bottle 21. The journal portion 23 is supported within the crankcase 2 by a bearing 24.

A crank gear 26 is provided at one end of the crankshaft 20, either integrally or separately. The crank gear 26 is a bevel gear and is engaged with the bevel gear 4 at one end of the rotary cylinder 3, so that it drives the rotary cylinder valve 3. The ratio of the number of teeth between the crank gear 26 and the bevel gear 4 is 1:
It is 2. The crank gear 26 rotates twice, while the bevel gear 4 rotates once.

One end of a connecting rod 30 is rotatably provided in the bin 21 of the crankshaft 20. A piston pin 31 is inserted into the other end of the connecting rod 30, and both ends of the piston pin 31 are fixed to a piston 32. The piston 32 has a structure that has been used in conventionally known four-stroke engines, and a detailed description thereof will be omitted. A pressure ring 33, 33 and an oil ring 34 are fitted into the grooves on the outer periphery of the piston 32, respectively.

The diagrams shown in FIGS. 2(a), (b), (C), and (d) show the seal ring 40 of the opening 5 of the rotary cylinder valve 4.
Shows the structure and shape of. FIG. 2(a) is a sectional view of the opening 5 of the rotary cylinder valve 4 taken in a direction perpendicular to the axis. FIG. 2(b) is a view seen from the direction of the arrow in FIG. 2(a), that is, from the inner hole. FIG. 2(C) is a view seen from the arrow C1 in FIG. 2(a), that is, from the outside. FIG. 2(d) is a sectional view taken along line dd in FIG. 2(C).

As can be understood from the figure, the opening 5 has an elongated inner hole of the rotary cylinder valve 3, and a circular outlet. If the inner hole is made circular, the opening 5 in the direction of movement of the piston 32 becomes larger, resulting in a lower compression ratio. That is, the piston ring 3 of the piston 32
3 is because gas leakage occurs when compressed beyond the opening 5.

At the outer peripheral surface 19 of the rotary cylinder valve 3 and at the opening 5
A seal ring 40 is disposed at a circumferential position. The seal ring 40 has an annular shape and a cylindrical curved surface along the outer circumferential surface 19 of the rotary cylinder valve 4 . A ring groove 41 is formed around the circumference of the opening 5 on the outer peripheral surface 19. A seal ring 40 is inserted into the ring groove 41. The ring groove 41 is the oil supply path 4
It communicates with 2.

On the other hand, the oil ring groove 42 communicates with an oil discharge path 43. The oil supply path 42 and the oil discharge path 43 are provided with holes in the axial direction of the rotary cylinder valve 4.
It communicates with the inside of crankcase 2. The crankcase 2 is filled with engine oil, and the crankshaft 2
0 is always accompanied in this way. Engine oil is supplied to the oil intake port 4 by rotating the rotary cylinder valve 4.
Oil is supplied from 4, and excess oil filling the ring groove 41 is returned to the crankcase 2 through an oil discharge path 43. Note that the oil intake port 44 is oriented in the direction in which the rotary cylinder valve 3 is connected to facilitate the intake of oil (FIG. 3).

On the other hand, the seal ring 40 has a roughly rectangular cross section and has oil through holes 45 at predetermined intervals on the outer periphery. The oil through hole 45 is configured to allow oil to seep out from the bottom surface of the ring groove 41 to the outer surface of the seal ring 40. The oil that seeps out to the surface fills the oil groove provided on the surface of the seal ring 4o. Seal ring 4
Similarly, an oil groove is provided on the bottom surface of o, and the oil is configured to flow between the oil through holes 45.

Further, a wave-shaped leaf spring 46 is inserted between the bottom surface of the ring groove 41 and the bottom surface of the seal ring 40.
The seal ring 4o is always pushed outward. The seal ring 4o is pressed against the inner peripheral wall surface of the rotary cylinder valve 4 to maintain airtightness.

At the top of the rotary cylinder valve 4 is an upper piston 5.
0 is inserted. The upper piston 5° is cylindrical in shape, closed at one end and open at the other end.

A piston ring 51.5 is attached to the outer periphery of the upper piston 50.
1. The oil ring 52 is inserted. The piston rings 51.51 are for maintaining airtightness between the rotary cylinder valve 3 and the upper piston 50.

A plug screw hole 54 is formed in the center of the end surface 53 of the upper piston 50. A spark plug 70 is attached to the plug screw hole 54. A plug storage hole 5 for storing a spark plug 70 is provided in the center of the upper piston 50.
5 is integrally formed. The upper end of the upper piston 50 is
A flange 56 is formed. The flange 56 has a plurality of circular guide holes 57 at equal angular positions. A guide pin 58 is slidably inserted into the guide hole 57 . The upper piston 50 can move while being slidably guided within the guide bin 58.

One end of the guide pin 58 is fixed within the disc plate 59, and the other end is fixed to the disc plate 60. Between the disc plate 59 and the disc plate 60, there is a washer 6.
1 is intervening. This washer 61 is for adjusting the distance between the disc plate 59 and the disc plate 60.

The bolts 62 fasten together the disc plate 60 and the washer 61. The disc plate 59 is fixed to the cylinder block 1 by bolts 63.

A spring receiver 65 is fixed to the center of the disc plate 60 with a bolt through a washer 64. A coil spring 66 is interposed between the spring receiver 65 and the inner end surface 67 of the upper piston 50. Therefore, the upper piston 50 is constantly pushed toward the piston 32 by the compression force of the coil spring 66. The washer 64 is used to adjust the strength of the coil spring 66.

What is shown in FIG. 4 is a developed view showing the shape of the suction hole 10 provided in the cylinder block 1. As shown in FIG. The height of the exhaust hole 15 and the suction hole 10 (as shown in the figure) is approximately the same size as the diameter of the opening 5. On both circumferential sides of the exhaust hole 15 and the suction hole 10, semicircular protrusions 11 having the same diameter as the suction hole 10 protrude. The two semicircular protrusions 11 are connected by a bridge part 12 . This bridge portion 12 is a piece that prevents the seal ring 40 from falling off. First, the exhaust hole (not shown), which has a similar shape and communicates with the suction hole 10 over a semicircumference of the circular opening 5 and has good suction efficiency, has a similar shape and will not be described again.

An engine having one or more structures operates as follows. Either crankshaft 20 is rotationally driven by a starter (not shown). When the piston 32 moves toward the bottom dead center, the opening 5 and the suction hole 10 coincide, and this opening 5
Inhale mixed gas from. Mixed gas A is supplied from a known vaporizer (not shown). The amount of intake air in this intake cycle reaches its maximum amount in the middle of the overlap between the opening 5 and the suction hole 10, decreases as the overlap approaches the end, and when the overlap ends, the intake also ends (FIG. 4).

At this time, since the crank gear 26 of the crankshaft 20 is driving the rotary cylinder valve 3, the timing is adjusted so that the opening 5 and the suction hole 10 coincide. The piston 32 moves toward the top dead center again, that is, compresses the mixed gas A.

This compression also causes the upper piston 50 to move slightly. That is, the coil spring 66 is compressed.

The flange 56 is guided by the bin 58 and the disc play 1-
Distance until it hits the stopper surface 67 of 60! move a lot. This moving distance is determined by a position that is balanced with the spring strength and compression pressure of the coil spring 66. Therefore, the flange 56 of the upper piston 50 has a distance of ! It doesn't necessarily have to move the height, it moves the maximum distance N! It's bamboo. The spring pressure of the coil spring 66 is determined by the compression ratio determined from the efficiency of the engine. Immediately before the piston 32 reaches top dead center, the opening 5 is located at the position of the spark plug 70,
The compressed mixed gas is ignited, and after the piston 32 reaches the top dead center, it is combusted and expanded.

The piston 32 is pushed by the combustion gas and moves, and the connecting rod 3
0. Drive the crankshaft 20 via the bin 21. At this time, at the same time, the upper piston 50 is once compressed by the exploded and combusted gas and compresses the coil spring 66, but the upper piston 50 returns to the position before compression. The exploded and combusted gas applies an averaged force to the piston 32 without pushing the piston 32 suddenly. The piston 32 rises again, the opening 5 and the exhaust hole 15 communicate with each other, and exhaust gas is exhausted from the exhaust hole 15 to the outside of the engine. Since the gap between the upper piston 50 and the piston 32 during this evacuation process is extremely small, the exhaust gas is almost completely exhausted. Repeat this operation thereafter.

[Second Embodiment] The diagram shown in FIG. 5 is a sectional view showing a second embodiment. In the embodiment described above, the upper piston 50 is fixed and rotates relative to the rotary cylinder valve 3. In this second embodiment, the rotary cylinder valve 3 and the upper piston 50 are rotated as one unit. A plate 80 is fixed to the upper part of the cylinder block 1 with bolts 81. A mounting hole 83 is formed in the center of the plate 80. A threaded cylinder 84 having a hollow center and threaded on its outer periphery is inserted into the mounting hole 83 . A lock nut 85.85 is screwed into this threaded cylinder 84, and the plate 80
Fix the threaded cylinder 84 to t). A flange 86 is integrally formed at the lower end of the threaded cylinder 84.

A coil spring 87 and a thrust bearing 88 are interposed between the upper piston 50 and the flange 86. Therefore, the rotary cylinder valve 3 and the upper piston 50 rotate together. The screw tube 84 and the coil spring 87 are fixed to the plate 80 and do not rotate. The spark plug 70 is similar to the conventional one, but rotates together with the upper piston 50. For this reason, the connection joint 89 of the electric wire between the spark plug and the ignition coil
is the provision. In this embodiment, since there is no relative rotation between the upper piston 50 and the rotary cylinder valve 3, it is easy to maintain airtightness between the upper piston 50 and the rotary cylinder valve 3.

[Other Examples] The spark plug 70 of the above-mentioned example has an upper piston 50.
It was to be fixed at The spark plug 70 does not necessarily have to be fixed to the upper piston 50. The sectional view shown in FIG. 6 is an example in which the cylinder pro-7 is provided on the side surface. During the compression stroke cycle, rotary cylinder valve 3
The spark plug 70 is provided in the cylinder block 71 so that the spark plug 70 is located in the opening 5 of the cylinder block 71. This has the effect of simplifying the engine head structure.

7(a) and 7(b) show other embodiments of the rotary cylinder valve 3. In FIG. The rotary cylinder valve 3 of the above embodiment had one seal ring 40. This embodiment is an example in which a seal ring 40 is provided. Since the seal ring 40 is provided in duplicate, the sealing performance is good. Moreover, the oil supply path 42 of this embodiment is
The opening is inclined by θ1 with respect to the central axis of the rotary cylinder valve 3.

The oil entering from the oil intake port 44 rises to the top due to the centrifugal force caused by the rotation of the rotary cylinder valve 3, and after supplying oil to the seal ring 40, the oil enters the oil discharge path 4.
It is discharged from 3. The oil discharge path 43 also forms an angle θ2 opposite to the angle θl with respect to the axis of the rotary cylinder valve 3.
It's only tilted. Therefore, the centrifugal force causes the component force to tilt and discharge becomes smooth. In addition, in this explanation, only the supply of oil to the seal ring 40 has been explained, but oil is similarly supplied to other necessary parts such as the oil ring 52 of the upper piston 50.

The ratio of the number of teeth between the crank gear 26 and the bevel gear 4 of the rotary cylinder valve 3 in the embodiment described above is 1:2. That is, the crank gear 26 rotates twice, while the bevel gear 4 rotates once. Since it is a 4-stroke engine, 4
The rotary cylinder valve 3 rotates once in each cycle. However, the intake hole 10, the exhaust hole, and the spark plug 7
If we place one 0 instead of one on the opposite side 180 degrees, we get 4.
Even if the rotary cylinder valve 3 is rotated at a ratio of 1:1, a 4-cycle engine is still possible.

This can be achieved by changing the fraction ratio of the gears of the rotary cylinder valve 3 and the bevel gear 4, or by interposing another gear to reduce the speed.The rotation speed of the rotary cylinder valve 3, which is difficult to seal with gas, can be achieved Therefore, gas leakage can be reduced compared to the previous embodiment. Further, the rotational friction loss can also be reduced compared to that of the previous embodiment. Note that these techniques are publicly known techniques such as Japanese Patent No. 135563 (1945) and Japanese Utility Model Publication No. 5704/1983.

The seal ring 40 of the opening 5 of the rotary cylinder valve 3 of the above embodiment was provided on the rotary cylinder valve 3 itself. As can be understood from the above explanation, the seal ring 4
0 is for preventing gas leakage between the rotary cylinder block 3 and the cylinder block 1. As long as this function is achieved, the seal ring 4o may be provided in either the cylinder block 1 or the rotary cylinder valve 3, and the shape and number of the seal rings are as follows:
The material is not limited to the embodiments described above, and any known material used in internal combustion engines may be used.

[Effects of the Invention] As detailed above, in the present invention, since the pistons are provided facing each other, the exhaust efficiency in the exhaust cycle is good.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of an opposed piston type rotary sleeve valve internal combustion engine, Fig. 2 (a>, (b), (C))
, (d) is a diagram showing the arrangement of the gas seal mechanism at the opening, Figure 3 is a sectional view of the oil intake port of the rotary cylinder valve, Figure 4' is an exploded view showing the shapes of the exhaust hole and suction hole, 5
The figure is a sectional view showing the second embodiment, FIG. 6 is a sectional view showing another embodiment in which the spark plug is provided on the side, and FIGS.
b) is a diagram showing another embodiment of the rotary cylinder valve.

Claims (1)

[Claims] 1. A cylinder block, a rotary cylinder valve,
In a sleeve valve internal combustion engine consisting of two opposing pistons and a crankshaft, the cylinder block has an intake hole and an exhaust hole for sucking in and discharging mixed gas and exhaust gas, and b. The rotary cylinder valve is rotatably supported within the cylinder block and has a cylindrical space at the center, and c) the rotary cylinder valve has an opening, and d has a gear at one end of the rotary cylinder valve. e. The two pistons are slidably inserted into the rotary cylinder valve facing each other across the opening, and f. The piston is connected to the one piston and rotatably provided on the connecting rod. a crankshaft; g) the other piston is movably opposed to the one piston with a spring interposed therebetween; and h) a crank gear provided on the crankshaft and meshing with the gear. Rotary sleeve valve internal combustion engine. 2. The rotary sleeve valve internal combustion engine according to claim 1, further comprising a seal ring disposed annularly around the opening to seal the intake hole and the exhaust hole. 3. The rotary sleeve valve internal combustion engine according to claim 1 or 2, wherein the other piston is fixed to the cylinder block so as to allow movement only in the axial direction of the rotary cylinder valve. 4. The rotary sleeve valve internal combustion engine according to claim 1 or 2, wherein the other piston is fixed to the rotary cylinder valve so as to allow movement of the rotary cylinder valve in an axial direction. 5. The rotary sleeve valve internal combustion engine according to claim 1, wherein the other piston cannot move beyond a certain distance against the spring. 6. The rotary sleeve valve internal combustion engine according to one of claims 1, 2, 3, 4, and 5, characterized in that a water pump or fins are provided on the outer periphery of the rotary cylinder valve.