CN2583363Y - Piston compensation rotary valve air inlet and exhaust engine - Google Patents

Abstract

A piston compensation rotary valve intake and exhaust engine, which removes the original valve lift type gas distribution mechanism of the engine, and installs a compensation piston in the cylinder head where the gas distribution mechanism was originally installed. There are three through holes on the side and the lower part, which communicate with the intake port, exhaust port and engine combustion chamber respectively; the rotating valve shaft crosses the space where the cylinder head body and the compensation piston intersect the aforementioned three holes, and the sprocket and chain wheel are fixed at the end. The wheel is connected with the transmission mechanism through a small chain, and a vent is dug on the circumference of the rotating valve shaft, and the vent is respectively connected to the combustion chamber, the air inlet and the exhaust port during the rotation of the valve shaft. A small compensation piston is also sleeved at the center of the upper part of the compensation piston. The lower end surface of the small compensation piston is arc-shaped and closely combined with the circumferential surface of the rotary valve shaft. The upper part has an elastic pressing mechanism. The advantages of the patent are that the engine power can be increased, the airtightness of the engine can be increased, the structure can be simplified, the volume can be reduced, the abrasion can be reduced, and the noise can be reduced.

Description

A piston compensation rotary valve intake and exhaust engine

technical field

The utility model belongs to the technical field of engines, in particular to a piston compensating rotary valve intake and exhaust engine for motorcycles.

technical background

Traditional engines have valve trains composed of rocker arms, rocker shafts, valve springs and valves, which have the following disadvantages:

1. The working engine needs to use part of the power to overcome the elastic force of the valve spring to complete the lifting of the valve and realize the gas distribution, so that the engine loses about 15% of power.

2. The generated reciprocating inertial force is large, and the phenomenon of detachment and rebound of the cam profile is prone to occur.

3. The gas pressure and heat load of the engine will cause the instantaneous distortion of the valve seat and the bending pressure of the valve neck and stem, which will reduce the sealing performance and thermal conductivity of the valve.

4. Due to the reciprocating inertial force of the valve spring, the rocker arm, cam profile, small chain and other components will be worn.

5. There are many moving parts in the gas distribution mechanism, and the engine noise is large, such as the noise generated by the valve clearance and the noise generated by the matching clearance of various components.

6. The structure is complex, there are many workpieces, and the assembly of the whole machine is relatively high.

Contents of the invention

The purpose of this utility model is to aim at the above-mentioned deficiencies existing in the existing engine, and to provide a piston compensating rotary valve intake and exhaust engine, which uses a piston compensating rotary valve to replace the original engine valve lifting type gas distribution mechanism, so as to improve the power of the engine and increase the engine capacity. Airtightness, simplified structure, reduced volume, reduced wear and noise.

The technical scheme of the utility model is as follows:

A piston compensated rotary valve intake and exhaust engine comprises a cylinder body, a crank connecting rod mechanism, a piston assembly and a transmission mechanism of a conventional engine. The improvement of the utility model is that: the original valve lifting type gas distribution mechanism of the engine is removed, and a compensation piston is installed in the cylinder head body where the gas distribution mechanism was originally installed. There are three through holes in the lower part of the cylinder head body, which communicate with the intake port and exhaust port on both sides of the cylinder head body and the combustion chamber of the engine; The sprocket is fixed at the bottom, and the sprocket is connected with the transmission mechanism of the engine through a small chain. The rotary valve shaft has a vent hole dug on the circumference corresponding to the intersection position of the aforementioned three holes. Combustion chamber with intake and exhaust ports.

In order to prevent gas crossover between the air inlet and the exhaust port, a small compensation piston is set in the center of the upper part of the compensation piston. It should be greater than the axial length of the air port on the rotary valve shaft, and there is an elastic compression mechanism on the small compensation piston.

The key of the utility model is to use the rotation of the rotary valve shaft to realize the opening and closing of the intake and exhaust passages of the engine, which replaces the original lift-type gas distribution mechanism. The speed ratio of the engine crankshaft to the rotating valve shaft is 2:1. The utility model has the advantages of:

1. It overcomes the shortcomings of the commonly used valve-lifting type gas distribution mechanism engine, such as complex structure, large inertial force, high overall height, many workpieces, and high processing precision requirements. The structure is simplified, the volume is reduced, and the whole machine is shortened, which is convenient for improving processing accuracy and installation.

2. The effective power of the engine is increased: the power of the original engine will be consumed by about 15% on the gas distribution mechanism. The engine of the utility model does not consume engine power due to the adoption of a rotary valve shaft type gas distribution structure. Therefore, the effective power of the engine can be increased by 15%.

3. Good airtightness and thermal conductivity: Overcoming the bending and deformation of the valve seat, valve neck and stem caused by the gas pressure and heat load of the original engine, which reduces the airtightness and thermal conductivity of the valve.

4. Noise reduction: Because the gas distribution of this engine is completed by a rotary valve shaft, the large and small compensation pistons are made around the rotary valve shaft under the action of spring lifting and compression within the tolerance range of parts. Small movements are pulsating parts, so the mechanical noise is relatively small.

The following is a comparison of the technical parameters of the original lifting valve of the engine and the rotary valve shaft type variable valve of the present invention: valve down variable valve Intake valve open before top dead center (°) exhaust valve closed after bottom dead center (°) 1040 644 Maximum opening area ^* 10 ² (mm ² ) 0.89 0.99 Total opening time (°) 230 230 Time face value ^* 10 ³ (mm ² °) Effective time face value (mm ² °) 120102 13399 Actual average static flow coefficient test Volumetric efficiency item Air loss % mesh 0.850.80 0.740.90 Mechanical loss % 100 40

Description of drawings

Fig. 1 is the overall mechanism figure of the utility model;

Fig. 2 is a structural diagram of the gas distribution part of the rotary valve shaft of the utility model;

Fig. 3 is a structural diagram of the utility model rotary valve shaft;

Fig. 4 is the A-A sectional view of Fig. 3;

Fig. 5 is a structural diagram of the compensation piston of the present invention;

Fig. 6 is a working principle diagram of the utility model;

Fig. 7 is the gas distribution phase diagram of the utility model.

Detailed ways

Referring to Fig. 1, the structure of this engine comprises the cylinder block of traditional engine, crank-connecting rod mechanism, piston assembly and transmission mechanism. The engine removes the original valve lift type gas distribution mechanism and replaces it with a rotary valve shaft type gas distribution structure.

Refer to Fig. 2, Fig. 3, Fig. 4 and Fig. 5 for the specific structure of the rotary valve shaft type gas distribution structure. A compensation piston 10 is installed in the cylinder head body 14 where the gas distribution mechanism was originally placed. The compensation piston 9 forms a double piston. The compensating piston 10 has three through holes A, B and C from the inside of the shaft to both sides and the bottom, respectively communicating with the intake port 2 and the exhaust port 13 on both sides of the cylinder head body 14 and the combustion chamber 3 of the engine. The rotary valve shaft 1 traverses the intersecting space between the cylinder head body 14 and the aforementioned three holes of the compensating piston 10 , and at the same time the circumferential surface of the rotary valve shaft 1 is tightly combined with the arc-shaped lower end surface of the small compensating piston 9 . A sprocket 17 is fixed on the end of the rotary valve shaft 1 protruding from the cylinder head body 14 , and the sprocket 19 is connected with the transmission mechanism of the engine by a small chain 20 . The rotary valve shaft 1 is dug with a fan-shaped vent 16 on the circumference corresponding to the intersection position of the aforementioned three holes, and the vent 16 is respectively connected to the combustion chamber 3, the intake port 2 and the exhaust port during the rotation of the rotary valve shaft 1. 13. The circumference of the ventilation opening 16 occupies 130°. In addition, the diameter of the small compensating piston 9 is greater than the axial length L of the vent opening on the rotary valve shaft 1 . In order to ensure the sealing of the combustion chamber when the engine is working and to prevent gas phase channeling between the intake port and the exhaust port, the compensation piston 10 is provided with an elastic lifting mechanism, and the small compensation piston 9 is provided with an elastic compression mechanism. The elastic lifting mechanism on the compensating piston 10 is made up of a lever 15, two groups of screws and a tension spring 11. The two ends of the lever 15 are fixed to the cylinder head body 14 by a group of screws 17A, and the other group of screws 17B passes through the lever 15 and the tension spring 11. The compensation piston 10 is connected, and the tension spring 11 is sheathed between the lever 15 and the nut. The elastic pressing mechanism of little compensation piston 9 is made of tension spring 12 and screw 18, and screw 18 is fixed on the lever 15, and tension spring 12 is contained in screw 18 between the groove that little compensation piston 9 tops go out. In this way, the tension spring 11 at the upper end of the compensating piston 10 is supported by the lever 15 to move the compensating piston 10 upwards to reach the zero clearance fit between the lower edge of the compensating piston 10 and the rotary valve shaft 1 to produce soft friction and ensure the sealing of the combustion chamber when the engine is working. Simultaneously, the small compensating piston 9 is pressed down by the support of the tension spring 12 and the lever 15, cutting off the air inlet 2 and the air outlet 13. In addition, in order to prevent air leakage between the inner wall of the compensation piston 10 and the outer circle of the small compensation piston 9, a piston ring 8 is provided, and piston rings 5 and 6 are provided to prevent air leakage in the combustion chamber. The exhaust port is provided with a piston ring 7. In addition, a spark plug 4 is also installed on the upper part of the combustion chamber 3 .

The working principle and gas distribution phase of the above gas distribution structure are shown in Figure 6 and Figure 7. The compression stroke is a, the power stroke is b, the exhaust stroke is c, and the intake stroke is d. The position of the point is set at 0°, because the rotational speed ratio of the crankshaft and the rotary valve shaft is 2:1, the crankshaft runs from 0° to 180°, the piston reaches the bottom dead center, and the rotary valve shaft rotates 90° to align with the exhaust port. The crankshaft runs from 180° to 360° from the piston to the top dead center, and the rotary valve shaft runs from 90° to 180°, so that the exhaust port is connected to the top port of the combustion chamber and then cut off. The crankshaft runs from a position of 360° to a position of 540°. The rotary valve shaft runs from 180° to 270° and cuts off after the top port of the combustion chamber communicates with the air inlet. The crankshaft runs from a position of 540° to 720° (ie 0°) when the piston reaches the top dead center to complete compression, and the rotary valve shaft runs from 270° to a position of 360°.

Claims (8)

1, a kind of piston compensated rotating valve intake and exhaust engine, comprise cylinder block, connecting rod, piston assembly and driving mechanism, it is characterized in that removing the original distribution device of motor, a compensating piston (10) is installed in the cylinder head body (14) of former arrangement distribution device, compensating piston (10) is provided with the elasticity lifting gear, compensating piston (10) has three through holes (A, B, C) to both sides and bottom in axle, communicate with the firing chamber (3) of suction port (2), relief opening (13) and the motor of cylinder head body (14) both sides respectively; Rotary valve shaft (1) passes across the crossing space of cylinder head body (14) and aforementioned three holes of compensating piston (10), end fixed chain wheels (19), sprocket wheel links to each other with the driving mechanism of motor by gimmal (20), rotary valve shaft (1) has dug a ventilating hole (16) on the circumference corresponding with aforementioned three hole intersection location, this ventilating hole is difference conducting firing chamber and suction port and relief opening in the rotary valve shaft rotary course.

2, piston compensated rotating valve intake and exhaust engine according to claim 1, it is characterized in that in compensating piston (10), also being with a little compensating piston (9), the lower end surface of little compensating piston (9) is curved, combine closely with the circumferential surface of rotary valve shaft (1), the diameter of little compensating piston (9) should be greater than the axial length L of the ventilating hole (16) on the rotary valve shaft (1), and little compensating piston (9) is gone up flexible hold-down mechanism.

3 piston compensated rotating valve intake and exhaust engines according to claim 1 and 2, it is 130 ° that the circumference that it is characterized in that the ventilating hole (16) on the rotary valve shaft (1) occupies amplitude.

4, piston compensated rotating valve intake and exhaust engine according to claim 1 and 2 is characterized in that three holes (A, B, C) should equate with the width K of ventilating hole (16) with the diameter of rotary valve shaft (1) contacting point.

5, piston compensated rotating valve intake and exhaust engine according to claim 1 and 2 is characterized in that all being equipped with piston ring on compensating piston (10) and the little compensating piston (9).

6, piston compensated rotating valve intake and exhaust engine according to claim 1 and 2, it is characterized in that the elasticity lifting gear on the compensating piston (10) is made up of a lever (15), two groups of screws (17A, 17B) and tension spring (11), lever (15) two ends are fixing by one group of screw (17A) and cylinder head body (14), another group screw (17B) passes lever (15) and is connected with compensating piston (10), and between lever (15) and nut overcoat tension spring (11).

7, piston compensated rotating valve intake and exhaust engine according to claim 6, the elastic compression mechanism that it is characterized in that little compensating piston (9) is made of tension spring (12) and screw (18), screw (18) is fixed on the lever (15), and tension spring (12) is loaded between the groove that screw leaves in little compensating piston top.

8,, it is characterized in that the ventilating hole (16) on the rotary valve shaft (1) is fan-shaped according to claim 1,2 or 7 described piston compensated rotating valve intake and exhaust engines.

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