JP2008038885A - Scotch yoke type gasoline engine with compression chambers - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-cycle internal-combustion engine having a combustion efficiency to the same degree as a four-cycle engine despite its two-cycle construction. <P>SOLUTION: Compression chambers are provided on both sides of each cylinder, and a crank pin formed at a yoke works with an offset angle of 0°-60° or 120°-180° with respect to the yoke moving direction, and a rotary bearing means to rotate freely is installed in the sliding part at the tip of the crank pin abutting on a long hole. The head of each piston is provided with a compression chamber having communication to the cylinder, and when one side of a two-head piston moves in the direction of increasing the volume of the compression chambers, it compresses the air in the two compression chambers, whereby one of the compression chambers serves evacuating the compression chamber after combustion while the other compression chamber supplies the mixture gas formed by mixing the fuel fed through a fuel supply passage with the air to the evacuated combustion chamber before the next combustion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a scotch yoke type gasoline engine having a compression chamber that provides the combustion efficiency of a four-cycle engine in two cycles by using a double-head piston with a center misalignment and interlocking the compression chamber with a time difference.

  Conventionally, in a Scotch yoke engine, the fuel supplied into the cylinder is compressed as the piston rises and becomes high pressure, and is ignited at the top dead center of the piston. The crankshaft is a mechanism for converting a linear motion into a rotational motion and giving a large rotational force to the output shaft.

  The piston side pressure reducing mechanism described in Patent Document 1 uses a scotch yoke mechanism, and the connecting rod connected to the piston is restrained so as to reciprocate on the cylinder axis without swinging. A crank pin of the crankshaft is slidably engaged with a long groove formed in a direction perpendicular to the cylinder axis at the large end of the rod. According to this scotch yoke mechanism, the connecting rod always reciprocates on the cylinder axis, thereby preventing the piston side pressure from being generated.

  The Scotch yoke engine described in Patent Document 2 includes a yoke, and a first piston and a second piston are attached to the yoke. The first piston and the second piston are provided so as to be capable of reciprocating with respect to a first cylinder and a second cylinder provided in parallel to each other at opposing positions. The first piston and the second piston are arranged at positions that are orthogonal to the reciprocating direction of each piston and relatively offset in a direction orthogonal to the axial direction of the crankshaft.

Patent Document 3 has a yoke provided with four pistons, and the crankshaft rotates as the yoke reciprocates. Further, the balancer shaft of the balancer rotates with the rotation of the crankshaft, and the inertial force accompanying the movement of the yoke is canceled by the centrifugal force of the balance weight attached to the balancer shaft and the counterweight provided on the yoke. . Further, an engine is disclosed in which the separation distance between the first balance weight and the first yoke matches the separation distance between the second balance weight and the second yoke, and cancels out the moment applied to the crankshaft.
Japanese Examined Patent Publication No. 63-56408 Patent Publication 2004-316576 Patent Publication 2005-61301

  In the above Patent Documents 1 to 3, all the yokes are moving at right angles to the reciprocating direction of the piston, dead points are generated at both ends of the groove, and the combustion efficiency is reduced when a two-cycle engine is used.

  The problem to be solved is to provide a reciprocating engine having an improved combustion efficiency equivalent to that of a cycle engine and engine output equivalent to that of a two-cycle engine by improving a Scotch yoke type engine with less mechanical loss.

The present invention includes a cylinder head having an ignition means at a head, a compression chamber having a communication path between an air valve and the cylinder head, a compression chamber having a communication path between an air valve, a fuel supply port, and the cylinder head, A compression chamber is a double-headed piston type scotch that reciprocates in each cylinder by connecting two pistons with a combustion chamber member composing a main chamber communicated through the communication passage and one common yoke. In the scotch yoke type gasoline engine equipped with a yoke mechanism,
The crank pin formed on the yoke has an offset angle of 0 ° to 60 ° or 120 ° to 180 ° with respect to the direction of movement of the yoke, and rotates on the sliding portion that contacts the elongated hole at the tip of the crank pin. A free rotation bearing means is provided, and a compression chamber constituting a part of the main chamber is formed in the piston head of the piston, and when one of the double-headed pistons moves in the direction of expanding the volume of the compression chamber. Two compression chambers compress the air, one of the compression chambers is exhausted from the compression chamber after combustion, and the other compression chamber is the fuel and air supplied from the fuel supply path. The mixed gas mixture was supplied to an exhausted compression chamber before the next combustion.

  In the present invention, at the top dead center of the piston, the shaft portion at the other end of the connecting rod attached to the circular body is pivotally supported so as to be positioned in the downward rotation direction of the piston in the circular body. Since the rotating bearing means arranged at the corners and the tip of the crankpin makes a smooth movement even when the moving direction of the crankpin is changed, the explosive force of the combustion chamber on the piston upper surface immediately becomes the rotational force of the output shaft, and the internal combustion engine In addition to increasing the torque force of the engine and improving fuel efficiency, it has a unique effect of obtaining a stable output at low engine speed.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings. In the following description, components having the same function are denoted by the same reference numerals, and repeated description thereof is omitted.

  The present invention is based on a reciprocating engine composed of only one misaligned double-headed piston, and FIG. 1 shows a cross-sectional view of the misaligned double-headed piston. The center line 4 of the first connecting rod 3 that supports the first piston 2 and the center line 7 of the second connecting rod 6 that supports the second piston 5 are separated by a distance X. Further, the locus extension line 10 of the crankpin 9 that reciprocates in the yoke 8 has an offset angle θ in the reciprocating direction of each piston, and this offset angle θ is preferably 30 ° to 60 °.

  FIG. 2 shows a state where the double-headed double-headed piston of the present invention is fitted to the crankshaft. The crank pin 9 slides along the groove while fitting into the yoke groove 8a.

  FIG. 3 is a cross-sectional view of the yoke 8 and the crankpin 9 cut in the crankshaft direction. A rotary bearing means 9 a is provided at the tip of the crank pin 9. As the rotary bearing means 9a, a rotary bearing, a fluororesin, a fluid bearing or the like can be considered. As a function of the rotary bearing means 9a, the crank pin 9 has a supporting function of smoothing the direction change in the sliding motion in the yoke groove 8a.

  FIG. 4 is a front view seen from the crankshaft 12 when the misaligned double-headed pistons 2 and 5 of the present invention are incorporated in the cylinders 10 and 11. The crank pin 9 is fitted in the groove 9 a of the yoke 8 and is slidable between the crank plates 13 and 14 provided on the crank shaft 12.

  FIG. 5 is a cross-sectional view of the compression chambers 15 and 19 provided on the left and right sides of the cylinder 10 and the cylinder 10. The compression chamber 15 is provided with a first intake valve 16 that is in contact with the cylinder 10, a first exhaust valve 17, and a first intake valve that communicates with outside air introduction means.

  The compression chamber 19 is provided with a second intake valve 20, a second exhaust valve 21, and a second intake valve and a fuel injection valve 22 that communicate with the outside air introduction means.

  For the above-mentioned various valves, conventional valves can also be used, but in a cylindrical case with a tunnel-shaped hole, it has a diameter slightly smaller than the diameter of this long hole, and has a hole that communicates the outer diameter and the inner diameter. By passing the pipe and rotating the pipe, when the hole of the case and the hole of the pipe coincide with each other, air or fuel flowing through the pipe is jetted into the case.

  6 (a) to 6 (e) show an example of a two-cycle operation in which the misaligned double-headed piston of the present invention uses the first and second compression chambers of FIG. As an operation, a cycle of (a) → (b) → (c) → (d) → (e) → (a) is repeated. At this time, in the piston on the opposite side (not shown), the cycle of (c) → (d) → (e) → (a) → (b) → (c) is repeated.

  In the following, the exhaust valve 25 is opened only in FIG. 6 (d), and is closed except in (d).

  First, in FIG. 6A, the first piston 2 has reached the top dead center, the first intake valve 16, the first exhaust valve 17, and the first intake valve 18 of the first compression chamber 15 are closed. The second intake valve 20, the second exhaust valve 21, the second intake valve 22, and the fuel injection valve 23 of the two compression chambers 19 are all closed.

  When the spark plug 24 is ignited, the air-fuel mixture compressed in the first cylinder 10 is ignited and explosion occurs. A pressing force is applied to the first piston 2, and at the same time, the second piston 5 is pushed up in the second cylinder 11.

  Next, in FIG. 6B, the air below the first piston in the first cylinder 10 is compressed and flows into the first compression chamber 15 from the first suction valve 16 and at the same time from the second suction valve 20 to the second compression. It also flows into the chamber 19 by compression. At this time, the first exhaust valve 17 and the first intake valve 18 in the first compression chamber 15 are sealed. The second exhaust valve 21 and the second intake valve 23 in the second compression chamber 19 are also sealed.

  Further, in FIG. 6C, the first cylinder 10 approaches the bottom dead center, and the first suction valve 16 of the first compression chamber 15 and the second suction valve 20 of the second compression chamber 19 are closed. At this time, the first exhaust valve 17 and the first intake valve 18 in the first compression chamber 15 are sealed. The second exhaust valve 21 and the second intake valve 23 in the second compression chamber 19 are also sealed.

  In the above, in the second cylinder 11, the second piston 5 approaches top dead center, and the compression rate reaches the highest point.

  Next, in FIG. 6D, the first piston 2 starts to rise in the first cylinder 10 and at the same time, the first exhaust valve 25 is opened to enter the exhaust process. Thereafter, the first exhaust valve 17 of the first compression chamber is released, and the compressed air that has been compressed in the first compression chamber 10 flows into the first cylinder 10, so that dirty air in the explosion is compressed air. It is exhausted out of the cylinder rapidly by forced exhaust.

  In the above, the 2nd piston 5 in the 2nd cylinder 11 descends, and air compresses and flows into the compression chamber of the 2nd piston lower part with air.

  Further, in FIG. 6 (e), the exhaust valve 17 of the first compression chamber 15 is closed and the exhaust valve 21 of the second compression chamber 19 is opened, so that the air that has been hermetically compressed in the second compression chamber. And a fuel mixture flows into the first cylinder 10.

  When the air-fuel mixture is stored in the first cylinder 10, the first intake valve 18 and the first exhaust valve 17 are simultaneously closed in the first compression chamber 15, so that the first intake valve 18 is opened. External air is sucked into the compression chamber 15.

  In the second compression chamber 19, the second intake valve 20 and the second discharge valve 21 are also closed, and at the same time, the second intake valve 22 is opened, so that external air is sucked into the second compression chamber 19. .

  The above is the principle of operation of a two-cylinder engine using a single misaligned double-headed piston, but a four-cylinder engine can be constructed by orthogonally crossing two misaligned double-headed pistons. Since the difference in the positions of these cylinder core lines is only the offset value X in FIG. 1, the engine is much shorter in the length direction of the crankshaft than the conventional in-line four-cylinder engine or V-shaped four-cylinder engine. For example, it is suitable for applications such as hybrid engines.

  Moreover, a 6-cylinder engine can be formed by configuring three pairs of misaligned double-headed pistons at different angles by 60 °.

  Further, an 8-cylinder engine can be configured by arranging two sets of 4-cylinder engines in which two misaligned double-headed pistons are orthogonal to each other in series and providing a clutch mechanism therebetween. This 8-cylinder engine uses the clutch mechanism to connect the clutch to drive all 8 cylinders when horsepower is needed, and to release the clutch mechanism when less horsepower is needed, thereby driving economically as a 4-cylinder engine. It becomes possible to do.

  The engine according to the present invention has a single-headed piston configuration, a configuration in which two or more cross-shaped configurations arranged orthogonally are connected, a configuration in which a plurality of double-headed pistons are arranged horizontally, and a configuration tailored to the application and vehicle design. It is possible, and since there is no rotating element like the conventional connecting rod and the conventional valve pinching angle becomes 0, the connecting rod storage part is downsized and the entire engine is downsized. For example, it is used for a hybrid engine etc. Can contribute to energy saving in the automobile industry.

Longitudinal front view of the centered double-headed piston of the present invention Figure 1 with cylinder and drive shaft attached Cross section of drive shaft and connecting rod Cross section of two cylinder engine The figure which attached the 1st and 2nd compression chamber to the 1st cylinder (A) to (e) Operation explanatory diagram of a two-cylinder engine

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Centerless double-headed piston, 2 ... 1st piston, 3 ... 1st connecting rod, 4 ... Core wire of 1st connecting rod, 5 ... 2nd piston, 6 ... 2nd connecting rod, 7 ... Core wire of 2nd connecting rod, 8 ... Yoke 9 ... Crank pin, 9a ... Yoke groove, 10 ... First cylinder,
DESCRIPTION OF SYMBOLS 11 ... 2nd cylinder, 12 ... Crankshaft, 13 ... Crankpin baseplate, 14 ... Crankpin baseplate, 15 ... 1st compression chamber, 16 ... 1st intake valve, 17 ... 1st discharge valve, 18 ... 1st intake valve , 19 ... second compression chamber, 20 ... second intake valve, 21 ... second discharge valve, 22 ... second intake valve, 23 ... fuel injection valve, 24 ... ignition plug, 25 ... exhaust valve.

Claims (1)

A cylinder head having an ignition means at the head, a compression chamber having a communication path between an air valve and the cylinder head, a compression chamber having a communication path between the air valve, a fuel supply port, and the cylinder head, and the compression chamber Combustion chamber members composing a main chamber communicated through the communication passage and two pistons are connected by one common yoke, and the piston has a double-headed piston type scotch yoke mechanism that reciprocates in each cylinder. In the scotch yoke type gasoline engine
The crank pin formed on the yoke has an offset angle of 0 ° to 60 ° or 120 ° to 180 ° with respect to the direction of movement of the yoke, and rotates on the sliding portion that contacts the elongated hole at the tip of the crank pin. A free rotation bearing means is provided, and a compression chamber constituting a part of the main chamber is formed in the piston head of the piston, and when one of the double-headed pistons moves in the direction of expanding the volume of the compression chamber Two compression chambers compress the air, one of the compression chambers is exhausted from the compression chamber after combustion, and the other compression chamber is the fuel and air supplied from the fuel supply path. A scotch yoke type gasoline engine having a compression chamber, wherein the mixed gas mixture is supplied to an exhausted compression chamber before the next combustion.

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