Two-cylinder range extender

Abstract

The two-cylinder range extender comprises an engine and an electric generator, the electric generator comprises an electric generator shell, a rotor assembly and a stator assembly, the rotor assembly is in key connection with the end of a crankshaft of the engine through a connecting shaft, the stator assembly is located outside the rotor assembly, and the electric generator shell is arranged on the stator assembly in a hot sleeving mode and fixedly connected with the engine. The engine is a two-cylinder engine, a mounting cavity is formed in a cylinder cover in the engine, the mounting cavity corresponds to and communicates with a combustion chamber of the engine, a pre-combustion connecting piece is installed in the mounting cavity in a pressed mode, a spark plug can be installed in the pre-combustion connecting piece, and the spark plug is installed in the pre-combustion connecting piece in a threaded mode and can form a pre-combustion cavity. The pre-combustion cavity is communicated with the combustion chamber in the engine, the efficiency of the engine is greatly improved and the oil consumption is reduced by adopting the pre-combustion cavity in the cylinder cover, the engine adopts a two-cylinder layout and is connected with the generator in a direct connection mode, the size is greatly reduced compared with that of a traditional product, and the cost is easier to control.

Description

Technical Field

[0001] The invention relates to the technical field of automobile machinery manufacturing, and in particular to a two-cylinder range extender. Background Art

[0002] The country vigorously develops new energy vehicles to promote China's transition from a large automobile country to a powerful automobile country. On the other hand, in order to respond to climate change, promote green development and attach great importance to energy conservation and emission reduction, electric vehicles have been vigorously promoted by the national environmental protection department for their zero emissions and low energy consumption.

[0003] Electric vehicles are equipped with on-board batteries to power the drive motor to drive the vehicle. On-board batteries are expensive, have limited power, and have a short driving range. They need to be frequently charged by external power sources, and their use conditions for long-term continuous driving are limited. If a range extender is installed in the car to charge the electric vehicle battery, the vehicle's driving range will be increased, which will not only reduce the dependence of the on-board battery on fixed charging piles, but also reduce the psychological burden on users when using the car.

[0004] The range extender products currently on the market have the following technical problems:

[0005] (1) The range extenders on the market are generally modified based on traditional engines, and are upgraded and remodeled. The overall structure has not been thoroughly improved, resulting in low efficiency and high fuel consumption;

[0006] (2) The range extenders on the market generally adopt a three-cylinder or four-cylinder layout, and a torque damper is provided between the engine crankshaft and the generator shaft, which makes the range extender longer, has large volume, and complex structure, making it impossible to carry it in small vehicles, and increases the cost. At the same time, the installation method is cumbersome and the assembly efficiency is low;

[0007] It can be seen that there is an urgent need to improve the range extender to solve the above-mentioned technical problems. Summary of the invention

[0008] In view of the above-mentioned technical problems existing in the existing range extenders, the purpose of the present invention is to provide a two-cylinder range extender, which greatly improves the efficiency of the engine and reduces fuel consumption by adopting pre-combustion chamber technology in the cylinder head. The engine adopts a two-cylinder layout and the engine and the generator are directly connected. The volume is greatly reduced compared with traditional products, the cost is easier to control, and it can well solve the problems existing in the prior art.

[0009] In order to achieve the above-mentioned object, the two-cylinder range extender provided by the present invention comprises an engine and a generator, wherein the generator comprises a generator housing, a rotor assembly, and a stator assembly, wherein the rotor assembly is key-connected to the end of the crankshaft of the engine via a connecting shaft, and the stator assembly is located outside the rotor assembly, wherein the generator housing is shrink-fitted to the stator assembly and fixedly connected to the engine, and the engine is a two-cylinder engine;

[0010] A mounting cavity is provided in the cylinder head of the engine, and the mounting cavity corresponds to and is connected to the combustion chamber of the engine, and a pre-combustion connecting piece is press-fitted in the mounting cavity, in which a spark plug can be installed, and the spark plug is threadedly installed in the pre-combustion connecting piece and can form a pre-combustion cavity, which is connected to the combustion chamber of the engine.

[0011] Furthermore, the engine comprises a cylinder block, a cylinder head, an oil pan, a crankshaft, and a shaft sleeve;

[0012] The top of the cylinder block is provided with two cylinder holes, the cylinder head is connected to the top of the cylinder block and defines a combustion chamber with the cylinder holes on the cylinder block, the oil pan is connected to the bottom of the cylinder block and forms a crankcase with the cylinder block, the crankcase is used to accommodate a crankshaft and engine oil, the crankshaft is fixed in the crankcase and extends from one side, the sleeve is fixedly connected to the end of the crankshaft, and the crankshaft is keyed to the connecting shaft through the sleeve.

[0013] Furthermore, a spline groove structure is provided at the end of the sleeve, and a spline structure corresponding to the spline groove structure is provided at the front end of the connecting shaft.

[0014] Furthermore, the pre-combustion connecting piece is press-fitted into the installation cavity by interference fit.

[0015] Furthermore, the pre-ignition connecting piece is a hollow tube structure with one end closed and the other end open. The inner surface of the pre-ignition connecting piece is provided with an internal thread, and the outer surface of the spark plug is provided with an external thread corresponding to the internal thread. The spark plug passes through the opening at one end of the pre-ignition connecting piece and is threadedly connected to the pre-ignition connecting piece. The spark plug can close the open end of the pre-ignition connecting piece and form a combustion cavity with the closed end of the pre-ignition connecting piece.

[0016] Furthermore, the pre-combustion cavity is a spherical structure.

[0017] Furthermore, a plurality of small holes are provided at the end of the pre-combustion cavity, and the pre-combustion cavity is connected with the combustion chamber through the plurality of small holes.

[0018] Compared with the prior art, the two-cylinder range extender provided by the present invention has the following beneficial effects:

[0019] (1) The range extender product provided by the present invention adopts a two-cylinder layout, which is much smaller in volume than traditional products, solving the problem that it cannot be installed in small vehicles;

[0020] (2) The range extender product provided by the present invention is a newly developed product, which adds pre-combustion chamber technology, and effectively controls fuel consumption and emissions;

[0021] (3) The engine design of the range extender product provided by the present invention takes into account the matching of the generator and the engine. The engine and the generator are designed with a direct connection structure, which is compact and small in size, easy to assemble, and fully utilizes the performance advantages of the range extender. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] Figure 1 This is a schematic structural diagram of the two-cylinder range extender provided by the present invention. Figure 2 This is a schematic cross-sectional structural diagram of a pre-combustion connector in a two-cylinder range extender provided by the present invention.

[0024] Illustration Description:

[0025] Engine 100, generator 200;

[0026] Cylinder block 110 , cylinder bore 111 , cylinder head 120 , mounting cavity 121 , oil pan 130 , crankshaft 140 , sleeve 150 , combustion chamber 160 , pre-combustion connector 170 , pre-combustion cavity 171 , spark plug 180 , generator housing 210 , rotor assembly 220 , stator assembly 230 , connecting shaft 240 . DETAILED DESCRIPTION

[0027] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0028] See also Figure 1 , which is a schematic structural diagram of a two-cylinder range extender provided by the present invention.

[0029] As can be seen from the figure, the two-cylinder range extender provided by the present invention includes two components: an engine 100 and a generator 200.

[0030] The two-cylinder range extender provided by the present invention is applied to new energy vehicles, and the engine 100 drives the generator 200 to rotate, so that the generator 200 generates electricity and continuously outputs electric energy to the battery in the new energy vehicle.

[0031] The generator 200 includes a generator housing 210, a rotor assembly 220, and a stator assembly 230. The rotor assembly 220 is key-connected to the crankshaft end of the engine 100 via a connecting shaft 240. The stator assembly 230 is located outside the rotor assembly 220. The generator housing 210 is heat-shrink-fitted onto the stator assembly 230 and fixedly connected to the engine 100.

[0032] Thus, the crankshaft 140 of the engine 100 drives the rotor assembly 220 of the generator 200 to rotate via the connecting shaft 240;

[0033] The engine 100 in this solution is a two-cylinder engine;

[0034] A mounting cavity 121 is provided in the cylinder head 120 in the engine 100, and the mounting cavity 121 corresponds to and is connected to the combustion chamber 160 of the engine 100, and a pre-ignition connecting piece 170 is pressurized in the mounting cavity 121, and the pre-ignition connecting piece 170 can be used for installing a spark plug 180 therein. The spark plug 180 is threadedly installed in the pre-ignition connecting piece 170 and can form a pre-ignition cavity 190, which is connected to the combustion chamber 160 in the engine 100.

[0035] Compared with a series of problems caused by the existing range extender using a three-cylinder or four-cylinder engine and a torque damper between the engine crankshaft and the generator shaft, the range extender provided by this solution uses a two-cylinder engine and the engine 100 and the generator 200 are directly connected, so that the length of the range extender becomes very small, the cost is reduced, and the installation method is simple, which improves the assembly efficiency.

[0036] Compared with the existing range extender that is a modification of the traditional engine, this solution is designed entirely for range extension purposes. A pre-combustion cavity is added in the cylinder head. The pre-combustion cavity can accelerate the combustion speed of the combustion chamber, reduce heat dissipation losses, suppress knock, increase the range extender's heat-to-work conversion efficiency, and improve fuel economy.

[0037] Specifically, the engine 100 includes a cylinder block 110 , a cylinder head 120 , an oil pan 130 , a crankshaft 140 , and a sleeve 150 ;

[0038] Two cylinder holes 111 are provided on the top of the cylinder block 110. The cylinder head 120 is connected to the top of the cylinder block 110 and defines a combustion chamber 160 with the cylinder holes 111 on the cylinder block 110.

[0039] The oil pan 130 is connected to the bottom of the cylinder block 110 and forms a crankcase with the cylinder block 110 , and the crankcase is used to contain a crankshaft 140 and engine oil;

[0040] The crankshaft 140 is fixed in the crankcase and extends from one side, the sleeve 150 is fixedly connected to the end of the crankshaft 140, and the crankshaft 140 is key-connected to the connecting shaft 240 through the sleeve 150;

[0041] In this solution, the sleeve 150 is preferably fixedly connected to the crankshaft 140 by bolts.

[0042] Furthermore, a spline groove structure is provided at the end of the sleeve 150, and a spline structure corresponding to the spline groove structure is provided at the front end of the connecting shaft 240. The connecting shaft 240 is inserted into the sleeve 150, and the spline structure cooperates with the spline groove structure to achieve circumferential fixation to transmit motion and torque.

[0043] Furthermore, the connecting shaft 240 and the shaft sleeve 150 are interference fit, so that the two are axially fixed.

[0044] Compared with traditional range extender products, the range extender product provided by the present invention has a reduced number of cylinders and adopts a dual-cylinder layout. The advantage of this is that by reducing the number of cylinders, the overall length dimension of the range extender becomes smaller, and the volume of the whole machine also becomes smaller, providing more space for vehicle layout.

[0045] As the number of cylinders decreases, the number of parts in each cylinder body decreases accordingly. For example, the piston, connecting rod and other parts are also eliminated. The overall weight becomes lighter, the number of parts is reduced, and the overall cost has a price advantage over the traditional range extender. While the number of cylinders is reduced, the advantage over the traditional range extender is that the weight of the entire range extender becomes lighter, which also has a positive effect on reducing the fuel consumption of the entire vehicle.

[0046] In order to further improve the fuel economy and emission level of the engine 100, a mounting cavity 121 corresponding to the combustion chamber 160 is provided on the cylinder head 120. The mounting cavity 121 is located above the combustion chamber 160 and communicates with the combustion chamber 160, and a pre-combustion connector 170 can be installed therein;

[0047] Furthermore, the pre-ignition connecting piece 170 is press-fitted into the installation cavity 121 by interference fit.

[0048] like Figure 2 The pre-ignition connector 170 is a hollow tube structure with one end closed and the other end open. The inner surface of the pre-ignition connector 170 is provided with an internal thread, and the outer surface of the spark plug 180 is provided with an external thread corresponding to the internal thread. The spark plug 180 passes through the opening at one end of the pre-ignition connector 170 and is threadedly connected to the pre-ignition connector 170. The spark plug 180 can close the open end of the pre-ignition connector 170 and form a combustion cavity 171 with the closed end of the pre-ignition connector 170.

[0049] The pre-combustion cavity 171 is a spherical structure;

[0050] The spherical structure at the end of the pre-combustion cavity 171 is provided with a plurality of small holes, and the pre-combustion cavity 171 is connected with the combustion chamber 160 through the plurality of small holes;

[0051] The mixed gas in the combustion chamber 160 is pressed into the pre-combustion cavity 171 so that the spark plug 180 ignites the mixed gas, and the ignited flame is ejected from the small hole to ignite the combustible mixed gas in the combustion chamber 160. Multiple ignition positions in the combustion chamber 160 can make the mixed gas burn faster and more completely to improve fuel economy and power.

[0052] In practice, the air-fuel mixture is injected or delivered into the combustion chamber 160 and during the compression stroke of the engine cycle, as the piston passes through the cylinder bore 111, the compressed air-fuel mixture is delivered through the small hole into the pre-combustion cavity 171. The spark plug 180 then ignites the air-fuel mixture in the pre-combustion cavity 171, producing sustained combustion very quickly and a flame front that expands rapidly and efficiently throughout the pre-combustion cavity 171.

[0053] The rapid ignition of the pre-combustion cavity 171 causes continuous combustion, allowing the engine 100 to use an increased compression ratio by consuming air-fuel before detonation or pre-ignition begins, which can speed up the combustion rate, reduce heat dissipation losses, while suppressing detonation, increasing the range extender's heat-to-work conversion efficiency, and improving fuel economy.

[0054] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A two-cylinder range extender, characterized in that: It includes an engine and a generator, wherein the generator includes a generator housing, a rotor assembly, and a stator assembly, wherein the rotor assembly is key-connected to the end of the crankshaft of the engine through a connecting shaft, and the stator assembly is located outside the rotor assembly, wherein the generator housing is shrink-fitted to the stator assembly and fixedly connected to the engine, and the engine is a two-cylinder engine; A mounting cavity is provided in the cylinder head of the engine, and the mounting cavity corresponds to and is connected to the combustion chamber of the engine, and a pre-combustion connecting piece is press-fitted in the mounting cavity, in which a spark plug can be installed, and the spark plug is threadedly installed in the pre-combustion connecting piece and can form a pre-combustion cavity, which is connected to the combustion chamber of the engine.

2. The two-cylinder range extender according to claim 1, characterized in that: The engine comprises a cylinder block, a cylinder head, an oil pan, a crankshaft and a shaft sleeve; The top of the cylinder block is provided with two cylinder holes, the cylinder head is connected to the top of the cylinder block and defines a combustion chamber with the cylinder holes on the cylinder block, the oil pan is connected to the bottom of the cylinder block and forms a crankcase with the cylinder block, the crankcase is used to accommodate a crankshaft and engine oil, the crankshaft is fixed in the crankcase and extends from one side, the sleeve is fixedly connected to the end of the crankshaft, and the crankshaft is keyed to the connecting shaft through the sleeve.

3. The two-cylinder range extender according to claim 2, characterized in that: The end of the shaft sleeve is provided with a spline groove structure, and the front end of the connecting shaft is provided with a spline structure corresponding to the spline groove structure.

4. The two-cylinder range extender according to claim 1, characterized in that: The pre-ignition connecting piece is interference-fitted with the installation cavity and is press-fitted in the installation cavity.

5. The two-cylinder range extender according to claim 1, characterized in that: The pre-ignition connecting piece is a hollow tube structure with one end closed and the other end open. The inner surface of the pre-ignition connecting piece is provided with an internal thread, and the outer surface of the spark plug is provided with an external thread corresponding to the internal thread. The spark plug passes through the opening at one end of the pre-ignition connecting piece and is threadedly connected to the pre-ignition connecting piece. The spark plug can close the open end of the pre-ignition connecting piece and form a combustion cavity with the closed end of the pre-ignition connecting piece.

6. The two-cylinder range extender according to claim 1, characterized in that: The pre-combustion cavity is a spherical structure.

7. The two-cylinder range extender according to claim 1, characterized in that: A plurality of small holes are arranged at the end of the pre-combustion cavity, and the pre-combustion cavity is connected with the combustion chamber through the plurality of small holes.

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