CN100434668C - A crankshaftless internal combustion engine - Google Patents

Abstract

A crankshaftless internal combustion engine relates to the field of gas power and belongs to a multi-cylinder internal combustion engine. The invention provides a new type of internal combustion engine, eight cylinders are evenly arranged around the gas distribution cam in an annular manner, the pistons of the cylinders directly act on the output cam, and the power is output from the output cam through the output shaft. The internal-combustion engine removes the connecting rod and crankshaft in the traditional internal-combustion engine, and the eight cylinders fully balance the forces on the output cam. The intake and exhaust valves of all cylinders are centrally controlled by two cams. The axis of the camshaft coincides with the axis of the output shaft, and the gas distribution timing is realized through the synchronous belt transmission mechanism, and the transmission ratio between the camshaft and the output shaft is relatively large. This kind of internal combustion engine has the characteristics of compact structure, stable operation of the whole machine, low noise, high power, and can realize high torque and low speed output.

Description

A crankshaftless internal combustion engine

technical field

The invention relates to the field of gas power, and belongs to a multi-cylinder internal combustion engine.

technical background

Most of the existing internal combustion engines are reciprocating piston internal combustion engines, which are divided into two strokes and four strokes. The linear motion of the cylinder piston is converted into rotary motion output by the slider crank mechanism. Due to the existence of the crank and connecting rod mechanism, the existing internal combustion engine has the disadvantages of long transmission chain, large impact, large vibration, and large noise. A two-stroke internal combustion engine can complete a working cycle during one revolution of the crankshaft, but part of the fresh combustible gas is discharged during the exhaust process, which is less economical than a four-stroke internal combustion engine. It discharges more dirt and pollutes the environment. The crankshaft of a four-stroke internal combustion engine rotates two weeks to complete a work cycle. Under the same volume and rotating speed, the theoretical power of a four-stroke internal combustion engine is 1/2 of that of a two-stroke internal combustion engine.

Movable gear transmission is a new type of transmission with superior performance, which has the advantages of large transmission ratio, strong bearing capacity and high efficiency. It is mainly composed of shock wave device, movable tooth frame, movable tooth and wave wheel, and all components are in the same plane. The movable tooth is in high contact with the shock wave device and the wave wheel, and the movable tooth pushes the wave wheel for continuous rotational motion under the action of the shock wave device to realize the conversion of motion. The push rod movable tooth transmission is a typical type of movable tooth transmission. The push rod movable tooth makes a reciprocating linear motion in the movable tooth frame to push the wave wheel to rotate.

If the movable tooth transmission technology is introduced into the internal combustion engine, the shortcoming of the poor economy of the two-stroke internal combustion engine can be overcome, and the shortcoming of the low power of the four-stroke internal combustion engine can be overcome.

Contents of the invention

The purpose of the present invention is to introduce the superior push rod movable gear transmission technology into the internal combustion engine, thereby providing a new internal combustion engine with compact structure, stable operation, low noise, low speed and high power.

The technical scheme of the present invention: convert the push rod movable tooth in the push rod movable tooth transmission into the cylinder piston of the internal combustion engine; convert the shock wave device in the movable tooth transmission into the gas distribution cam of the internal combustion engine; convert the push rod movable The wave wheel in the tooth transmission is transformed into an output cam; the eight cylinders are arranged in a ring around the gas distribution cam to realize the centralized control of gas distribution; the arrangement of the camshaft of the traditional internal combustion engine is changed so that the axes of the camshaft and the output shaft coincide; the internal combustion engine The valve timing control of the engine is realized by the synchronous belt transmission mechanism.

Description of drawings

Figure 1 Schematic diagram of internal combustion engine without crankshaft

Figure 2 Schematic diagram of internal combustion engine without crankshaft

Figure 3 The output cam keeps in contact with the roller under the action of the cylinder spring

Figure 4 Schematic diagram of cylinder structure

Figure 5 intake valve control cam

Figure 6 Exhaust valve control cam

Among the figure: 1, frame, 2, output shaft, 3, output cam, 4, roller, 5, piston, 6, cylinder, 7, end cover, 8, exhaust valve, 9, exhaust cam, 10, Synchronous pulley, 11, valve camshaft, 12, synchronous belt, 13, intake cam, 14, intake valve, 15, pulley shaft, 16, bearing

Specific embodiments of the invention

The working principle of this internal combustion engine is as shown in Figure 1, and eight cylinders (6) are fixed. Among them, the pistons in the I and V cylinders are at the top dead center position, the ignition plug is ignited, the gas burns and expands to push the pistons to do work, and the work stroke starts, the piston (5) starts to move and pushes the output cam (3) through the roller (4) Rotate clockwise, the output cam and the output shaft are fixedly connected together, so that the output shaft rotates clockwise; the pistons in cylinders II and VI are at the bottom dead center position, and the pistons are pushed by the output cam to discharge the gas out of the cylinder. The stroke starts; the pistons in cylinders III and VII are at the top dead center position, and the pistons move to the bottom dead center under the action of the output cam, the volume of the cylinder increases, and the suction stroke starts; the pistons in cylinders IV and VIII are at the bottom dead center Point position, the piston moves to the top dead center under the action of the output cam, the volume of the cylinder decreases, the gas in the cylinder is pressurized, and the compression stroke begins. When the output cam turns over 45°, cylinders IV and VIII are in the state of starting the power stroke, cylinders I and V are in the state of starting the exhaust stroke, cylinders II and VI are in the state of starting the suction stroke, and cylinders III and VII are in the state of starting the exhaust stroke. The number cylinder is at the beginning of the compression stroke. Such a cycle goes round and round, and the output shaft can rotate stably all the time.

From the above, it can be seen that at any one moment, among the eight cylinders, two cylinders are in the power stroke, two cylinders are in the exhaust stroke, two cylinders are in the suction stroke, and two cylinders are in the compression stroke. The working state of the two cylinders with a phase difference of 180° is exactly the same. The comprehensive effect of each piston on the output cam is only the effect of force couple, not force, so the internal combustion engine works smoothly, with low noise and small vibration impact.

The structure of this internal combustion engine is shown in Figure 2, and the end cover (7) is fixed on the frame (1), and eight cylinders (6) are fixed on the end cover (7), and the piston (5) in the cylinder is equipped with a roller The roller (4), the roller (4) is in contact with the output cam (3), the output cam (3) is fixedly connected with the output shaft (2), and the output shaft (2) is supported on the frame (1) by two rolling bearings. superior. Two gas distribution cams (9, 13) are fixed on the gas distribution camshaft (11), and one end of the gas distribution camshaft (11) is supported on the output shaft (2), and the other end is supported on the end cover (7). The output shaft transmits power to the valve camshaft (11) through four timing belt pulleys (10), two timing belts (12) and a pulley shaft (15), so as to realize the valve timing.

There are two ways to connect the piston and the output cam: the first way is shown in Figure 1, the piston roller is installed in the annular groove on the output cam to ensure the contact between the piston roller and the output cam. The second method is shown in Figure 3. The piston contacts the inner contour of the output cam through the roller. In order to ensure that the roller is always in contact with the output cam, a cylinder spring should be installed in the guide cylinder.

The structure of the cylinder is shown in Figure 4. It is composed of two cylinders, one large and one small, connected in series. The small cylinder is the combustion chamber, where the work of gas expansion is completed; the large cylinder is the guide cylinder, which guides the movement of the piston. As a result, the guide cylinder mainly bears the positive pressure exerted by the piston on the cylinder wall, and the positive pressure exerted by the piston on the combustion cylinder is relatively small. This structure is beneficial to reduce the wear and tear of the combustion cylinder and improve its service life. The cylinder piston is composed of two pistons, one large and one small, and a piston rod. When the cylinder piston moves in the cylinder, the gas volume between the large and small pistons will change. Therefore, several vent holes should be opened on the large piston to facilitate gas flow. This structure is also conducive to the heat dissipation of the small piston. In order to prevent the piston from rotating around the axis of the cylinder and the phenomenon that the piston roller is out of contact with the output cam, the cross-sectional shape of the pilot cylinder is a rounded rectangle.

The eight cylinders of the internal combustion engine have sixteen valve valves in total, which are centrally controlled by two valve cams, the intake cam controls eight intake valves, and the exhaust cam controls eight exhaust valves. The opening and closing conditions of each valve are shown in Table 1. The shapes of the intake cam and the exhaust cam are exactly the same, they are all fixed on the cam frame, and the phase difference between the two is only 45°, and their shapes are shown in Figure 5 and Figure 6. Table 1 Valve opening and closing situation table

inhale compression work Exhaust Intake valve open close close close exhaust valve close close close open

It can be seen from Fig. 5 that the gas distribution cam rotates once, and the cylinder piston completes two cycles. It can be seen from Figure 1 that every time the piston completes a working cycle, the output cam turns two teeth. Therefore, for every revolution of the valve cam, the output cam turns four teeth. The number of teeth of the output cam is generally a multiple of 4. In Figure 1, the output cam has 12 teeth in total, so the transmission ratio between the output shaft and the valve camshaft is 1:3. If the number of teeth of the output wheel is 16 teeth, the The transmission ratio is 1:4. The transmission ratio between the crankshaft and the camshaft of a traditional four-stroke internal combustion engine is 1:1. It can be seen that, compared with the traditional internal combustion engine, this internal combustion engine can realize low-speed output and has the function of a reducer.

It can be seen from Figure 1 that the distance between the stress point of the output cam and its center of rotation is relatively large, so the force exerted by the piston on it can generate a relatively large output torque.

The contour curve of the output cam is generally a spline curve, which is simple for processing and manufacturing, and a combination of simple lines, such as a combination of arcs and straight lines, can also be used. The profile curve of the output cam is completely symmetrical, so that the internal combustion engine can run both forward and reverse, and its direction of rotation is determined by the starting direction.

It can be seen from the above analysis that the working states of the two cylinders with a phase difference of 180° are exactly the same. The comprehensive effect of each piston on the output cam is only the action of a force couple, and there is no action of force, so the output cam can rotate stably. Due to the large radius of the output cams and their solid connection with the output shaft, they have a large moment of inertia. When the positional relationship between the output cam and the cylinder is shown in Figure 1, it is at the dead point, and the output cam can pass through the dead point by inertial force.

For the oil pumping system, the timing system under ignition, the lubricating system and the cooling system not involved in the present invention, it can be realized by directly borrowing the mature technology of the existing internal combustion engine.

Claims (7)

1, a kind of crankless internal-combustion engines, this internal-combustion engine is mainly by frame (1), output shaft (2), output cam (3), roller (4), piston (5), cylinder (6), end cap (7), exhaust valve (8), exhaust cam (9), synchronous pulley (10), distribution cam axle (11), be with synchronously (12), intake cam (13), intake valve (14), belt shaft (15), bearing (16) is formed, it is characterized in that: cancelled connecting rod and the bent axle in the traditional combustion engine, eight cylinders are evenly arranged in around the valve cam, cylinder piston acts directly on the output cam, the rotation of promotion output cam, output cam and output shaft fixed connection are realized kinetic energy output together; The complete machine running steadily; The axis of distribution cam axle and the dead in line of output shaft; The valve timing of cylinder is realized by synchronous belt drive mechanism; Can realize low speed, high pulling torque output.

2, internal-combustion engine according to claim 1, it is characterized in that: cylinder piston acts directly on the output cam, the rotation of promotion output cam, output cam and output shaft fixed connection are together, thereby with kinetic energy output, do not have the bent axle and the connecting rod of traditional combustion engine in this internal-combustion engine, each piston is to the active force complete equilibrium of output cam, complete machine running balance, impact, vibration, noise are all less.

3, internal-combustion engine according to claim 1 is characterized in that: output shaft is bearing on the frame, and distribution cam axle one end bearing is on output shaft, and the other end is bearing on the end cap, and the axis of distribution cam axle and the axis of output shaft are point-blank.

4, internal-combustion engine according to claim 1 is characterized in that: eight cylinders are evenly arranged in around two valve cams, and eight intake valves are controlled by a cam, and eight exhaust valves are by another cam control.

5, internal-combustion engine according to claim 1 is characterized in that: valve timing is realized that by synchronous belt drive mechanism output shaft transmits motion on the distribution cam axle by four synchronous pulleys, two synchronous bands and a belt shaft.

6, internal-combustion engine according to claim 1 is characterized in that: the rotating ratio of distribution cam axle and output shaft is 3 or bigger, compares with traditional combustion engine, can realize the output shaft low-speed running.

7, internal-combustion engine according to claim 1 is characterized in that: the force bearing point of output cam and the distance of its gyration center are bigger, and piston can produce bigger torque to the active force of output cam.

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