JPH08178010A - Motion converter and reciprocating engine - Google Patents

Abstract

PURPOSE: To efficiently convert the reciprocating motion into the rotating motion and obtain a high output at low fuel consumption by providing a reciprocating member and a rotatable cylindrical member, and forming endless spiral grooves on the peripheral face of the cylindrical member to be coupled with part of the reciprocating member. CONSTITUTION: A V-type two-cylinder engine is formed at the bank angle of 90 deg., an inner hole 18 closed at the upper end and opened at the lower end is formed concentrically with a cylinder on a piston 12 reciprocated in the stroke chamber 14 of each cylinder, and a cylindrical shaft 20 is slidably inserted into the inner hole 18. A pair of crossing spiral grooves 22, 24 are formed on the outer periphery of the shaft 20. Bosses 26, 28 fixed to the piston 12 and integrally lowered when the piston 12 is lowered are coupled with a pair of spiral grooves 22, 24, the shaft 20 is rotated CCW, and the rotation is transmitted to a straight shaft 34 via the meshing of bevel gears 30, 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion converting device for converting reciprocating motion into rotary motion, and vice versa. The former motion conversion device is particularly suitably applied as a reciprocating engine used as a power source for various transportation facilities and industrial machines. In addition, the latter motion conversion device can be applied to, for example, an air compressor or a pump that uses a motor as a drive source.

[0002]

2. Description of the Related Art A typical example of a motion conversion device that converts reciprocating motion into rotary motion to obtain power is an internal combustion engine that uses gasoline or light oil as fuel. Today, reciprocating engines are the mainstream of such internal combustion engines. Reciprocating engines are roughly classified into gasoline engines that use gasoline as fuel and diesel engines that use light oil as fuel. Used as a source. In these reciprocating engines, an air-fuel mixture of fuel and air is ignited in a compressed state to explosively combust, and the expansion pressure accompanying this is converted into a reciprocating motion of a piston to obtain power.

In a four-cycle engine, which is a typical automobile engine, for example, the piston makes two reciprocations during four strokes of intake, compression, explosion and exhaust, as is well known. That is, when the piston descends with the intake valve open to the combustion chamber formed at the top of the cylinder open, a negative pressure is created in the cylinder, and the mixture of gasoline and air is drawn into the combustion chamber through the intake valve. After that (intake stroke), the intake valve is closed, and the piston turns upward to compress the air-fuel mixture in the combustion chamber (compression stroke). When the piston reaches the top dead center, it is ignited through the spark plug to explosively burn the air-fuel mixture, and the expansion pressure at that time pushes down the piston (explosion stroke). The piston turns up again after reaching the bottom dead center, but at this time, the exhaust valve is opened to discharge the combustion exhaust gas to the outside of the cylinder (exhaust stroke). Reciprocating motion of the piston is obtained by repeating the above four strokes. Then, the reciprocating motion of the piston is converted into rotary motion via the connecting rod and the crankshaft connected to the lower end of the piston, and power for rotating the drive wheels of the automobile is obtained.

[0004]

As described above, in the conventional reciprocating engine, the connecting rod and the crankshaft are generally used to convert the reciprocating motion of the piston into the rotary motion.
The reciprocating motion of the piston, which reciprocates twice during the explosive and exhaust strokes, is converted through the connecting rod and the crankshaft to obtain a rotary motion of two revolutions. Therefore, in order to obtain a high rotation speed, it is necessary to reciprocate the piston at a speed corresponding thereto, which increases fuel consumption. That is, from the viewpoint of resource saving, it is earnestly desired to develop an engine that can obtain high output with low fuel consumption.

In addition, the crankshaft is required to have strength and rigidity to withstand a large load associated with the reciprocating motion of the piston acting through the connecting rod, and to achieve balanced and smooth high speed rotation. Various characteristics are required. From these viewpoints, the crankshaft is generally manufactured as an integrally molded product by forging, but the manufacturing cost increases due to its extremely complicated shape, which is one of the factors that increase the manufacturing cost of the entire engine. .

Furthermore, the length of the crank arm that bulges radially outward from the center of rotation of the crankshaft requires half the piston stroke from top dead center to bottom dead center in the piston reciprocating motion. Therefore, if the piston stroke is lengthened in order to increase the displacement, the crank arm lengthens proportionately. It is desired to design the engine as compact as possible in order to secure the space of the passenger part of the passenger car and the cargo bed part of the freight car,
For this reason, a multi-cylinder engine is arranged in a V-type or in a vertical arrangement, but the problem of lengthening the engine due to the use of a crankshaft has not yet been solved.

[0007]

Therefore, the present invention provides a motion conversion device for converting reciprocating motion into rotary motion, or conversely converting rotary motion into reciprocating motion, based on a novel idea completely different from the prior art. The purpose is to do. In particular, with regard to the device for converting the piston reciprocating motion into the rotary motion in the reciprocating engine, it is proposed to break away from the conventional concept that is composed of the connecting rod and the crankshaft and to construct it based on a completely new idea. is there.

That is, the present invention comprises a member that reciprocates,
A cylindrical member, which cannot move in the reciprocating direction of the reciprocating member but is rotatably supported by itself, is formed on the circumferential surface of the cylindrical member to fit a part of the reciprocating member. And an endless spiral groove for converting the reciprocating motion of the reciprocating member into a rotary motion of the cylindrical member through fitting of a part of the reciprocating member and the endless spiral groove. It is a motion conversion device.

Further, according to the present invention, the rotating member, the reciprocating member capable of reciprocating in the direction of the rotating shaft of the rotating member, and the endless member formed on the circumferential surface of the rotating member so as to fit a part of the reciprocating member. And a spiral groove, and converts the rotary motion of the rotary member into the reciprocal motion of the reciprocating member through the fitting of the reciprocating member and the endless spiral groove.

Further, the reciprocating engine according to the present invention is
A cylinder having a combustion chamber in the upper portion, a piston that reciprocates in the cylinder chamber due to fuel combustion in the combustion chamber,
A cylindrical shaft member that is accommodated in the inner hole of the piston and is rotatable relative to the cylinder; a protruding member that is integrally provided on either the piston or the cylindrical shaft member; An endless spiral groove formed on the other side of the shaft member to which a protruding member can be fitted, and the reciprocating motion of the piston is rotated by the fitting of the protruding member and the endless spiral groove to the rotation of the cylindrical shaft member. A reciprocating engine characterized by being configured to be converted into motion.

A multi-cylinder reciprocating engine is provided by providing a plurality of single-cylinder engines having the above-mentioned structure to make them multi-cylinder.

According to one preferred configuration example in this case,
A cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and a first gear that rotates integrally with the cylindrical member is fixed to each of the lower ends thereof. And the first in each single cylinder engine
A second gear that meshes with each of the gears is fixed to the straight shaft, and the rotation of the cylindrical member in each single-cylinder engine is transmitted to the straight shaft.

Each single-cylinder engine may be arranged radially with respect to the axial direction of the straight shaft, or
It may be arranged around the straight shaft in parallel with the axial direction.

According to another preferred mode of the multi-cylinder reciprocating engine of the present invention, the cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and its lower end. A first gear that rotates integrally with the cylindrical member is fixed to each of the
The second gear is fixed to the first straight shaft by the second gear.
Is meshed with the third gear fixed to the second straight shaft, and thus the first straight shaft and the second straight shaft can simultaneously rotate in opposite directions. To be done.

According to still another preferred aspect of the multi-cylinder reciprocating engine of the present invention, the cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and at the lower end thereof. A first gear that rotates integrally with the cylindrical member is fixed, and in the first group of a plurality of single-cylinder engines, the first gear is fixed to the first straight shaft. The first straight shaft is rotated in one direction by meshing with the second gear, and in the remaining second group of the plurality of single cylinder engines, the first gear is fixed to the second straight shaft. It is configured to mesh with a gear and rotate the second straight shaft in a direction opposite to that of the first straight shaft.

[0016]

The operation of the motion converting mechanism in the reciprocating engine according to the present invention will be described with reference to FIG. The rotating shaft 1 is arranged in a lower portion inside a cylinder (not shown). The rotary shaft 1 is rotatably inserted in a center hole of a piston (not shown).

On the outer peripheral surface of the rotary shaft 1, a pair of spiral grooves 2 and 3 are engraved as shown. One spiral groove 2
Starts from the upper end point a, passes through the point b intersecting with the other spiral groove 3, passes through the intermediate point c, and then gradually descends on the outer peripheral surface on the opposite side of the rotary shaft 1 at the intermediate point d. After crossing the other spiral groove 3, it further descends to reach the lower end point e, then turns to ascends, passes through a point e intersecting the other spiral groove 3, passes through the intermediate point c again, and then on the opposite side. It gradually rises on the outer peripheral surface, intersects with the other spiral groove 3 at its intermediate point g, then further rises, and returns to the upper end point a. That is, the spiral groove 2 makes one revolution on the outer peripheral surface of the rotary shaft 1 while reaching the lower end point e through the upper end points a to b, c, d, and the lower end points e to f, c ,. Similarly, it makes one revolution on the outer peripheral surface of the rotary shaft 1 before returning to the upper end point a through each point g.

The other spiral groove 3 is 1 with respect to the above spiral groove 2.
It is formed at a position shifted by 80 degrees, and the top point h,
The intersection g on the opposite outer peripheral surface, the intermediate point i, the intersection f, the lower end point j, the intersection d on the opposite outer peripheral surface, the intermediate point i, and the intersection b are passed in this order to return to the point h. In this spiral groove 3 as well, it makes one revolution on the outer peripheral surface of the rotating shaft 1 from the upper end point h to the lower end point j, and makes one revolution on the outer peripheral surface of the rotating shaft 1 before returning from the lower end point j to the upper end point h. Rotate.

A pair of bosses 4 and 5 projecting into the spiral grooves 2 and 3 are arranged so as to face each other. These bosses 4 and 5 reciprocate up and down together with the piston, and when the piston is at the top dead center, the boss 4 projects into the upper end point a of the spiral groove 2 and the boss 5 projects into the upper end point h of the spiral groove 3. ing. When the piston descends from this state and reaches an intermediate point between the top dead center and the bottom dead center, the boss 4 moves from the point a to the point c via the point c while being guided by the spiral groove 2. The boss 5 is guided by the spiral groove 3 and moves from the point h to the point i via the point g. By the downward movement of the bosses 4 and 5, the rotary shaft 1 rotates 180 degrees counterclockwise in the drawing. When the piston subsequently descends and reaches the bottom dead center, the boss 4 moves in the spiral groove 2 from the point c to the lower end point e via the point d, and the boss 5 moves in the spiral groove 3 from the point i to the point f. To the lower end point j, and by the downward movement of the bosses 4 and 5, the rotary shaft 1 further rotates counterclockwise by 180 degrees. That is, the rotating shaft 1 makes one rotation while the piston descends from the top dead center to the bottom dead center. Similarly, the rotating shaft makes one rotation while the piston rises from the bottom dead center to the top dead center.

As described above, the reciprocating motion of the piston is converted into the rotary motion of the rotary shaft, and the desired rotary motion can be obtained without using the crankshaft. The spiral grooved shaft and the protruding member (boss) fitted in the spiral groove required for the present invention can be easily processed and manufactured by a known method.

It will be understood from FIG. 1 that the present invention can also function as a motion conversion device for converting rotary motion into reciprocating motion. That is, when the shaft 1 is rotated by a motor (not shown) or the like, the pistons integrated with the bosses 4 and 5 reciprocate due to the fitting between the bosses 4 and 5 and the spiral grooves 2 and 3.

[0022]

FIG. 2 shows an embodiment in which the present invention is applied to a V type two cylinder engine. In this embodiment, the cylinders 10 and 10a are arranged in a V shape with a bank angle of 90 degrees.

Since the cylinders 10 and 10a have substantially the same structure, the structure of the cylinder 10 will be described below. Inside the cylinder 10, a stroke chamber 14 for accommodating the piston 12 and allowing a reciprocating motion of a predetermined stroke, and a combustion chamber 16 at the top are provided. Although the combustion chamber 16 is shown as a substantially hemispherical type combustion chamber in this example, the combustion chamber 16 is not limited to this, and is configured as a multi-spherical type, wedge type, pentaroof type combustion chamber or the like. May be.

The combustion chamber 16 is communicated with an intake manifold for sucking a mixture of gasoline and air and an exhaust manifold for exhausting combustion exhaust gas. Further, the intake manifold and the exhaust manifold are respectively intake and exhaust. An intake valve and an exhaust valve for controlling the above are arranged, but since these respective members are publicly known, no particular explanation is required,
Therefore, the illustration is omitted.

The piston 12 reciprocates in the stroke chamber 14 of the cylinder 10 in the axial direction. That is, as described above, it reciprocates twice during four strokes of intake, compression, explosion, and exhaust. In FIG. 2, the piston 12 in the cylinder 10 is shown at top dead center, and in this state, the piston 12a in the other cylinder 10a is located at bottom dead center.

An inner hole 18 having an upper end closed and an opened lower end is formed concentrically with the cylinder 10 in the piston 12, and a cylindrical shaft 20 can be accommodated in the inner hole 18. The shaft 20 is the cylinder 10.
Is immovable in the axial direction, and axial movement restricting means (not shown) for this purpose is provided. Also, shaft 2
0 is rotatable with respect to the piston 12, and the inner surface of the inner hole 18 slidingly contacting the shaft 20 and the inner surface of the bottom opening 11 of the cylinder 10 allow relative rotation of lubricating oil, bearings, white metal, or the like smoothly. Means (not shown) for doing so are provided.

A pair of spiral grooves 22 and 24 intersecting with each other are engraved on the outer peripheral surface of the shaft 20. The pair of spiral grooves 22, 24 are shown as being substantially the same as the spiral grooves 2, 3 in the example of FIG. 1 described above. That is, the spiral groove 22 goes around the outer peripheral surface of the shaft 20 from the upper end point 22 a to the lower end point 22 b, and the lower end point 22
By the time it returns from b to the upper end point 22a, the outer peripheral surface of the shaft 20 makes another round in the same direction. Similarly, the spiral groove 24 extends from the upper end point 24a to the lower end point 24b of the shaft 20.
The outer peripheral surface of the shaft 20 is rotated once, and the outer peripheral surface of the shaft 20 is rotated once again in the same direction before returning from the lower end point 24b to the upper end point 24a.

On the bottom surface portion 13 of the piston 12, bosses 26 and 28 projecting toward the inner hole 18 are arranged opposite to each other at intervals of 180 degrees. The bosses 26 and 28 are fitted into the spiral grooves 22 and 24 in a non-separable manner. When the piston 12 is located at the top dead center shown in the figure, the boss 26 moves into the spiral groove 22.
Is fitted to the upper end point 22 a of the spiral groove 24, and the boss 28 is fitted to the upper end point 24 a of the spiral groove 24. The bosses 26 and 28 are fixed to the piston bottom portion 13, and therefore the piston 1
It reciprocates in the stroke chamber 14 of the cylinder 10 together with 2.

The shaft 20 is a bottom opening 1 of the cylinder 10.
1, and a bevel gear 30 is fixed to the lower end thereof. Bevel gear 30 meshes with bevel gear 32 fixed to straight shaft 34, and transmits the rotation of shaft 20 to straight shaft 34 to rotate it.

As is apparent from the above construction, the piston 12 moves from the top dead center position shown in FIG.
When descending inside, the bosses 26, 28 that are fixedly attached to the piston 12 and integrally descend are formed in the spiral groove 22 of the shaft 20,
Since the shafts 20 are fitted to the shafts 24,
Is rotated counterclockwise in the figure. Since the spiral grooves 22 and 24 make one round around the outer peripheral surface of the shaft 20 from the upper end points 22a and 24a to the lower end points 22b and 24b, the piston 12 moves downward from the top dead center position to the bottom dead center position. In the meantime, the shaft 20 makes one rotation. Similarly, the spiral grooves 22 and 24 move from the lower end points 22b and 24b to the upper end point 22.
Since the outer peripheral surface of the shaft 20 is rotated once before returning to a and 24a, the shaft 20 makes one rotation while the piston 12 moves upward from the bottom dead center to the top dead center.

Therefore, in the four-cycle engine, the shaft 20 makes four revolutions with respect to the piston 12 that reciprocates twice during a series of intake, compression, explosion and exhaust strokes.
The rotation of the shaft 20 is transmitted to the straight shaft 34 via the bevel gears 30 and 32, and the straight shaft 34 is rotated at a rotation speed according to the speed ratio between these bevel gears. For example, when the bevel gear 30 that is a drive gear has 20 teeth and the bevel gear 32 that is a driven gear has 10 teeth, the speed ratio is 2, and the piston 12 is used in a series of strokes of intake, compression, explosion, and exhaust. The straight shaft 34 makes eight revolutions during two round trips.

The same operation as described above is performed for the other cylinder 10a, the reciprocating motion of the piston 12a in the stroke chamber 14a is converted into the rotational motion of the shaft 20a, and the bevel gears 30a and 32 are meshed with each other. The straight shaft 34 is rotated through.

A flywheel 36 is further fixed to the straight shaft 34. As in the conventional engine, a starter gear (not shown) is meshed with the outer periphery of the flywheel 36, and a starter motor (not shown) is provided.
The engine can be started by.

Since the piston 12 reciprocates only in its axial direction, it is necessary to provide means for preventing its rotational movement. When the piston rotates, it becomes difficult or impossible to transfer the movement of the piston to the grooved shaft 20.

As shown in FIG. 3, when the piston 12 has an elliptical cross-sectional shape, the rotation of the piston 12 in the cylinder 10 can be prevented and the interference with the rotation of the shaft 20 can be prevented.

The rotation of the straight shaft 34 depends on the number of turns of the spiral grooves 22 and 24 and the gear ratio between the bevel gears 30 and 32. Therefore, with proper selection of these, the reciprocating engine can be designed to produce maximum output with minimum fuel consumption.

Many of the parts and elements used in reciprocating engines of conventional design can also be used in the present invention. Further, as for many related devices including a cooling mechanism, a lubrication device, an electric system, an exhaust system, etc., the same devices as those in the related art can be used. Furthermore, in the reciprocating engine of the present invention, it is not necessary to use a crankshaft that requires high-precision machining, and this can be replaced with a straight shaft having a simple structure. These greatly reduce the manufacturing cost of the reciprocating engine of the present invention.

When the reciprocating engine is used as a power source for an automobile or the like, a multi-cylinder reciprocating engine is generally used to obtain a high output by integrating outputs from a plurality of cylinders. According to the present invention having the basic structure described above, it is possible to provide various novel designs for the multi-cylinder reciprocating engine.

FIG. 2 shows an example of the structure of the V-type two-cylinder engine as described above. The two cylinders 10 and 10a in this configuration example are radially arranged with respect to the axial direction of the straight shaft 34 that receives the transmission of the engine output.
They are arranged in bank angles of degrees.

Similarly, three cylinders 10, 10a, 10
FIG. 4 shows a configuration example in which b is arranged in a T shape at a bank angle of 90 degrees. In FIG. 4, cylinders 10a and 10b
Are horizontally opposed to each other, but may be arranged in a V-shape with an appropriate bank angle between them. The structure and operation of the cylinder 10b are the same as those of the cylinders 10 and 1 described above.
The description is omitted because it is substantially the same as 0a.

Although not shown, four cylinders may be arranged radially in the X-type or + -type with respect to the axial direction of the straight shaft to form a four-cylinder engine.

Further, as described above, a plurality of sets may be arranged with an arrangement configuration of a plurality of cylinders radially arranged with respect to the axial direction of the straight shaft, with a required interval in the axial direction of the straight shaft. It is possible. For example, a compact 6-cylinder engine can be obtained by arranging two sets of the T-type 3-cylinder engine shown in FIG. 4 at intervals in the axial direction of the straight shaft. Similarly, by arranging two sets of X-type or + -type four-cylinder engines-straight shafts at intervals in the axial direction,
A compact 8-cylinder engine can be obtained.

FIGS. 5 and 6 show a multi-cylinder reciprocating engine having a different design. Such a cylinder arrangement is not possible with the prior art.
In this embodiment, four cylinders 40a to 40d are arranged around the straight shaft 50 in parallel with the axial direction thereof. The cylinders 40a to 40d have substantially the same configuration and operation as the cylinders 10 and 10a described above. In each shaft, the grooved shafts 42a to 42d are rotated by the reciprocating motion of the pistons 44a to 44d. Gears 46a to 46d are fixed to the lower ends of the grooved shafts 42a to 42d, respectively, and these gears are all meshed with the gear 48 fixed to the straight shaft 50. A flywheel 52 is further fixed to the straight shaft 50. It will be appreciated that a four-cylinder engine designed in this way is extremely compact, especially in its radial dimension about the straight shaft 50. The rotation of the straight shaft 50 depends on the gear ratio between the gears 46a-46d and 48 and the shaft 4
It depends on the combination with the number of turns of the groove formed in 2a to 42d.

FIG. 7 shows a multi-cylinder reciprocating engine of yet another design. This embodiment is configured so that the first shaft 52a and the second shaft 52b can be simultaneously rotated in opposite directions. Flywheels 64a and 64b are fixed to the first and second shafts 52a and 52b, respectively. The construction and operation of the cylinders 54a to 54f used in this embodiment are substantially the same as those of the cylinders 10 and 10a described above, and the bevel gears 58a to 58a to the lower ends of the grooved shafts 56a to 56f housed therein, respectively. 58f is fixed.

Of these bevel gears, bevel gears 58a and 58b mesh with a first bevel gear 60a fixed to the first shaft 52a, and bevel gears 58e and 58f are fixed to the second shaft 52b. 1 bevel gear 62a meshes, and bevel gears 58c and 58d are the first shaft 52a.
Second bevel gear 60b and second shaft 52 fixed to the
It meshes with both the second bevel gears 62b fixed to b.

With the above configuration, in the embodiment shown in FIG.
The first shaft 52a is rotated in the direction of the arrow by the reciprocating motion of the pistons in the four cylinders 54a to 54d, and the second shaft 52b is rotated in the rotating direction of the first shaft 52a by the reciprocating motion of the pistons in the four cylinders 54c to 54f. Rotate in the direction of the arrow shown, which is the opposite direction. In other words, although this engine is a 6-cylinder engine, the two shafts 52a and 52b are respectively 4
It is rotationally driven by a cylinder engine, and a 4-cylinder engine is 2
It is possible to give the same engine output as the one equipped. It is particularly preferable to use the engine having such a design by mounting it on a high performance sports type car or a four-wheel drive vehicle.

FIG. 8 shows an air compressor as an application example of a motion converting device for converting rotary motion into reciprocating motion.
The air compressor 66 uses an electric motor 68 as a power source, and a shaft 72 with a groove is connected to an output shaft 68 a of the air compressor 66 via a reduction gear 70. A piston 74 having an oval cross section (see FIG. 3) is reciprocally housed in an oval cross section piston chamber 76 of a cylinder 78.
The grooved shaft 72 is accommodated in the inner hole 80 of the piston 74 so as to be relatively movable. As will be understood from the description made with reference to FIG. 1, the rotation of the motor 68 is reduced by the reduction gear 70 at a predetermined reduction ratio, and then transmitted to the grooved shaft 72, so that the protrusion member of the piston 74 (not shown). )
And the spiral groove 82 of the shaft 72 are fitted to reciprocate the piston 74 in the chamber 76. Therefore,
The air sucked from the intake port 84 when the piston 74 moves leftward in the drawing is exhausted from the exhaust port 86 when the piston 74 moves rightward in the drawing. A plurality of cylinders 78 may be connected to one motor 68 via an arbitrary gear device.

[0048]

According to the present invention, reciprocal motion can be converted into rotary motion, and conversely, rotary motion can be converted into reciprocal motion.

The present invention is particularly preferably applied to a reciprocating engine used as a power source for automobiles and the like, and is adopted as a mechanism for converting the reciprocating motion of a piston into a rotary motion instead of the conventional connecting rod and crankshaft. can do.

According to the present invention, by appropriately selecting the rotational speed of the spiral groove and the gear ratio, it is possible to freely obtain the rotational speed of the straight shaft in a wide range with respect to the reciprocating motion of the piston. High output can be generated with fuel efficiency.

The reciprocating engine of the present invention uses an engine block having the same shape and structure as the existing engine, and the cooling engine, the lubrication system, the electric system, the exhaust system and the like can be the same as the existing engine. Therefore, the existing equipment can be used for engine processing and assembly, and it is excellent in economic efficiency.

Furthermore, since the crankshaft manufactured by using special forged steel and requiring a high degree of processing and assembly technology is not required, and a straight shaft that can be manufactured at low cost can be replaced, the manufacturing cost of the engine as a whole can be reduced. Significantly reduced.

Further, the miniaturization of the engine is achieved, and it is possible to increase the space for passenger and freight loading. For example, when a V-type 8-cylinder engine is designed based on the technical idea of the present invention, its axial dimension can be reduced to the same extent as that of an in-line 4-cylinder engine, which is significantly smaller than a conventional multi-cylinder engine. Can be achieved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the operating principle of the present invention.

FIG. 2 is a sectional view showing a schematic configuration of a V-type 2-cylinder reciprocating engine according to an embodiment of the present invention.

3 is a cross-sectional view taken along the line III-III of one cylinder in the engine of FIG.

FIG. 4 is a sectional view showing a schematic configuration of a T-type three-cylinder reciprocating engine according to another embodiment of the present invention.

FIG. 5 is a sectional view showing a schematic configuration of a four-cylinder reciprocating engine according to still another embodiment of the present invention.

6 is a cross-sectional view taken along the line VI-VI in FIG.

FIG. 7 is a sectional view showing a schematic configuration of a 6-cylinder reciprocating engine according to still another embodiment of the present invention, in which two shafts are simultaneously rotated in opposite directions.

FIG. 8 is a sectional view showing a schematic configuration of an air compressor according to still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotary shaft 2, 3 spiral groove 4, 5 boss 10 cylinder 12 piston 18 inner hole 20 shaft 22, 24 spiral groove 26, 28 boss 30 bevel gear 32 bevel gear 34 straight shaft

Claims (9)

[Claims] 1. A reciprocating member, a cylindrical member which cannot move in the reciprocating direction of the reciprocating member but is rotatably supported by itself, and a part of the reciprocating member. In order to fit, the endless spiral groove formed on the circumferential surface of the cylindrical member, and the reciprocating member through the fitting of a part of the reciprocating member and the endless spiral groove. A motion conversion device, which converts reciprocating motion into rotational motion of the cylindrical member. 2. A rotating member, a reciprocating member capable of reciprocating in a rotating shaft direction of the rotating member, and an endless member formed on a circumferential surface of the rotating member to fit a part of the reciprocating member. A motion converting device comprising a spiral groove, and converting the rotary motion of the rotating member into the reciprocating motion of the reciprocating member through the fitting of the reciprocating member and the endless spiral groove. . 3. A cylinder having a combustion chamber in the upper portion, a piston that reciprocates in the cylinder chamber due to fuel combustion in the combustion chamber, and a piston that is accommodated in an inner hole of the piston and is supported relative to the cylinder. A rotatable cylindrical shaft member, and a protruding member integrally provided on either the piston or the cylindrical shaft member,
An endless spiral groove formed on the other side of the piston or the cylindrical shaft member and capable of fitting the protruding member, and the piston is formed by fitting the protruding member and the endless spiral groove. A reciprocating engine configured to convert the reciprocating motion of the above into a rotary motion of the cylindrical shaft member. 4. The reciprocating engine according to claim 3, wherein a plurality of single-cylinder engines having the structure according to claim 3 are provided to form a multi-cylinder engine. 5. The cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and has a lower end that rotates integrally with the cylindrical member. One gear is fixed, and a second gear that meshes with each of the first gears in each single-cylinder engine is fixed to a straight shaft, and rotation of the cylindrical member in each single-cylinder engine is performed. Is transmitted to the straight shaft. The reciprocating engine according to claim 4, wherein 6. The reciprocating engine according to claim 4, wherein the single-cylinder engines are arranged radially in the axial direction of the straight shaft. 7. The reciprocating engine according to claim 4, wherein the single-cylinder engines are arranged around the straight shaft in parallel with the axial direction of the straight shaft. 8. The cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and has a lower end that rotates integrally with the cylindrical member. A first gear is fixed, and the first gear meshes with a second gear fixed to the first straight shaft and a third gear fixed to the second straight shaft. The reciprocating engine according to claim 4, wherein the first straight shaft and the second straight shaft can be simultaneously rotated in opposite directions. 9. The cylindrical member in each of the plurality of single-cylinder engines extends downward through the bottom surface of the cylinder, and has a lower end that rotates integrally with the cylindrical member. A first gear is fixed, and in the first group of the plurality of single-cylinder engines, the first gear meshes with a second gear fixed to a first straight shaft to form the first gear. Rotating the straight shaft in one direction so that in the remaining second group of the plurality of single cylinder engines, the first gear is the second
The third straight shaft is engaged with a third gear to rotate the second straight shaft in a direction opposite to that of the first straight shaft. Reciprocating engine.