CN109854367B - Single-cylinder free piston engine and working method thereof - Google Patents

Abstract

The application relates to the technical field of engines, in particular to a single-cylinder free piston engine and a working method thereof, wherein the single-cylinder free piston engine comprises: the device comprises a cylinder body, a motor shell, a base, a piston motion assembly and a coil; the motor shell is connected with the cylinder body, and the coil is positioned on the inner wall of the motor shell; a channel is arranged in the cylinder body and is communicated with the inside of the motor shell to form a movement cavity; the piston movement assembly comprises a guide shaft, a piston, a permanent magnet and a spring; the guide shaft is positioned in the motor shell, the permanent magnet is connected with the piston, and the piston is sleeved on the guide shaft; the piston can drive the permanent magnet to reciprocate in the motion cavity along the guide shaft, and the magnetic induction line of the cutting coil generates electricity; the spring is used for reversely pushing the piston to realize reciprocating motion; an air inlet valve is arranged on the base, and air enters a channel of the cylinder body to be mixed with oil gas and burnt, so that the piston is driven to reciprocate.

Description

Single-cylinder free piston engine and working method thereof

Technical Field

The application relates to the technical field of engines, in particular to a single-cylinder free piston engine and a working method thereof.

Background

At present, new energy power is a future development trend, and the common new energy power in the current market mainly comprises pure electric power and oil-electricity mixture, so that the pure electric vehicle has the advantages of strong power, quietness, small vibration, energy saving, long mileage endurance and the like due to the fact that the pure electric vehicle is limited by the endurance mileage, the power assembly is large in size and heavy in mass, and the problems of low thermal efficiency and the like of the traditional internal combustion engine still exist.

Disclosure of Invention

The application aims to provide a single-cylinder free piston engine and a working method thereof, which are used for solving the technical problems of large volume, heavy weight and low thermal efficiency of a power mixing assembly taking oil-electricity mixing as new energy power in the prior art.

The application provides a single cylinder free piston engine, comprising: the device comprises a cylinder body, a motor shell, a base, a piston motion assembly and a coil;

The motor comprises a motor shell, a cylinder body, a coil, a base, a motor and a coil, wherein the base is arranged at one end of the motor shell, the other end of the motor shell is connected with the cylinder body, and the coil is positioned on the inner wall of the motor shell; a channel is arranged in the cylinder body and is communicated with the inside of the motor shell to form a movement cavity;

The piston motion assembly comprises a guide shaft, a piston, a permanent magnet and a spring; the guide shaft is positioned in the motor shell, and one end of the guide shaft is connected with the base; the permanent magnet is connected with the piston, and the piston is sleeved on the guide shaft; the piston can drive the permanent magnet to reciprocate in the motion cavity along the axial direction of the guide shaft and is used for cutting the magnetic induction line of the coil; the spring is also sleeved on the guide shaft, one end of the spring is connected with the base, and the other end of the spring is connected with the piston through a spring seat;

The base is provided with an air inlet valve, the cylinder body is provided with an air inlet channel, and the air inlet valve is communicated with the air inlet channel through the movement cavity.

Further, a cylinder cover is arranged at one end of the cylinder body, which is far away from the motor shell, and an oil sprayer and a spark plug are embedded on the cylinder cover;

the fuel injector is used for injecting fuel into the passage, and the spark plug is used for igniting a mixture of oil and air placed in the passage.

Further, an exhaust passage is further arranged on the cylinder body, one end of the exhaust passage is communicated with a passage of the cylinder body, and the other end of the exhaust passage is communicated with the outside.

Further, the air inlet valve is a one-way valve.

Further, the piston is of a stepped shaft structure, one end of the piston is a head part, and the other end of the piston is a tail part; the head can extend into the engine cylinder;

the head of the piston is provided with a wedge-shaped structure for generating vortex flow of gas in the engine cylinder.

Further, an inner hole is formed in the piston along the axial direction of the piston, the inner hole penetrates through the tail of the piston, and the piston is sleeved on the guide shaft through the inner hole;

The piston is of a peach-shaped cam-shaped structure with the cross section of the guide shaft, and the piston is matched with the guide shaft.

Further, a sensor is arranged at the position, close to the tail part of the piston, of the guide shaft, and signal teeth are arranged on the piston.

Further, the signal teeth comprise top dead center signal teeth and bottom dead center signal teeth, the top dead center signal teeth are arranged at the head part of the piston, and the bottom dead center signal teeth are arranged between the head part and the tail part of the piston;

The number of the top dead center signal teeth is one, the number of the bottom dead center signal teeth is two, and the connecting line of the positions of the top dead center signal teeth and the two bottom dead center signal teeth is parallel to the axis of the piston.

Further, the piston is provided with a vent hole, and the vent hole is communicated with the inner hole; the number of the vent holes is a plurality of, and the vent holes are uniformly arranged along the circumferential direction of the piston.

The application also provides a working method of the single-cylinder free piston engine, which comprises the following steps:

The one-way valve opens the air intake, and the air enters the channel of the cylinder body through the gap between the permanent magnet and the coil assembly and the inside of the engine shell;

Simultaneously, the coil of the engine is reversely electrified, so that a magnetic field opposite to the permanent magnet is generated by the coil, the permanent magnet and the piston are pushed to move along the guide axial base end under the repulsive force of the reverse magnetic field, the spring is compressed, and the piston reaches the first position; a sensor in the piston detects a bottom dead center position signal and controls an oil injector to inject oil into a channel of the cylinder body;

The compressed spring generates pushing force to the permanent magnet and the piston to push the permanent magnet and the piston to move along the guide axial cylinder end, and the piston reaches a second position; the sensor in the piston detects a top dead center position signal, the igniter is controlled to ignite, gas and oil in the channel are combusted, generated smoke pushes the permanent magnet and the piston to move along the guide axial base end again, the spring is compressed, the piston reaches a first position, and the oil injector injects oil; the compression pushes the permanent magnet and the piston to move along the guide axial cylinder end again, the piston reaches a second position, and the igniter ignites;

The permanent magnet and the piston reciprocate between the first position and the second position, the oil spraying and ignition processes are repeated, and the permanent magnet cuts the magnetic induction line of the coil to generate electricity, so that continuous electricity generation is realized.

Compared with the prior art, the application has the beneficial effects that:

the application provides a single cylinder free piston engine, comprising: the device comprises a cylinder body, a motor shell, a base, a piston motion assembly and a coil; one end of the motor shell is provided with a base, and the base and the motor shell can be connected through screws; the other end of the motor shell is connected with the cylinder body, and the coil is positioned on the inner wall of the motor shell; a channel is arranged in the cylinder body and is communicated with the inside of the motor shell to form a movement cavity, and the piston assembly is positioned in the movement space and can move along the axial direction of the movement cavity so as to cut the magnetic induction line of the coil; the direct current generator is integrated outside the motor shell, so that the permanent magnet can generate electricity when the magnetic induction wire is cut.

The piston motion assembly comprises a guide shaft, a piston, a permanent magnet and a spring, wherein the guide shaft is arranged along the axial direction of the motion cavity, the piston is fixedly connected with the permanent magnet, and the piston is sleeved on the guide shaft to drive the permanent magnet to move along the guide shaft; the guide shaft plays a guide role in the movement of the piston and the permanent magnet, so that the piston can reciprocate between the cylinder body channel and the motor shell along the fixed direction, the situations of offset and the like can not occur, and the magnetic induction line cutting process is more stable. And a spring is arranged between the piston and the base and is used for pushing the piston to make the piston reciprocate.

In addition, an air inlet valve is further arranged on the base, an air inlet channel is formed in the cylinder body and is communicated with the movement cavity, so that air entering the motor shell through the air inlet valve enters the air inlet channel of the cylinder body through a gap between the coil and the permanent magnet, then enters the channel of the cylinder body from the air inlet channel of the cylinder body, the channel of the cylinder body serves as a combustion chamber, and air is mixed with air injection and ignited to burn in the combustion chamber, and the piston is given with driving force, so that the piston can reciprocate.

The single-cylinder free piston engine of the embodiment of the application has the following specific working processes: the air inlet valve is opened for air inlet, and the air enters the channel of the cylinder body through the gap between the permanent magnet and the coil assembly and the inside of the engine shell; the coil of the engine is reversely electrified, so that a magnetic field opposite to the permanent magnet is generated by the coil, the permanent magnet and the piston are pushed to move along the guide axial base end under the repulsive force of the reverse magnetic field, the spring is compressed, and the piston reaches a first position; the fuel injector injects fuel into a channel of the cylinder body; the compressed spring generates pushing force to the permanent magnet and the piston to push the permanent magnet and the piston to move along the guide axial cylinder end, and the piston reaches a second position; igniting the igniter, burning gas and oil in the combustion chamber, pushing the permanent magnet and the piston to move along the guide axial base end again by generated smoke, compressing the spring, enabling the piston to reach a first position, and injecting oil by the oil injector; the compression pushes the permanent magnet and the piston to move along the guide axial cylinder end again, the piston reaches a second position, and the igniter ignites; the permanent magnet and the piston reciprocate between the first position and the second position, the oil spraying and ignition processes are repeated, and the permanent magnet cuts the magnetic induction line of the coil to generate electricity, so that continuous electricity generation is realized.

In conclusion, the single-cylinder free piston engine disclosed by the application adopts a mature and simple two-stroke working principle, has the advantages of small volume, light weight, high mechanical efficiency, small energy conversion loss, low self-starting and vibration, low maintenance cost and the like, and effectively improves the endurance mileage of the whole vehicle driving motor.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present application, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the overall structure of a single cylinder free piston engine according to an embodiment of the present application;

Fig. 2 is a schematic diagram of an internal structure of a single cylinder free piston engine (a schematic diagram of a piston in a second position) when the single cylinder free piston engine according to an embodiment of the present application is in operation;

FIG. 3 is a schematic view of the internal structure of a single cylinder free piston engine according to an embodiment of the present application (the piston is in a first position and a second position);

fig. 4 is a schematic diagram of an internal structure of a single cylinder free piston engine (a schematic diagram of a piston in a first position) when the single cylinder free piston engine according to an embodiment of the present application is in operation;

FIG. 5 is a schematic diagram of the positional relationship and structure of a piston and a guide shaft of a single cylinder free piston engine according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a piston of a single cylinder free piston engine according to an embodiment of the present application in a first view;

FIG. 7 is a schematic diagram of a piston of a single cylinder free piston engine according to an embodiment of the present application in a second view;

FIG. 8 is a schematic diagram of a guide shaft of a single cylinder free piston engine according to an embodiment of the present application;

Fig. 9 is a schematic structural view of a piston of a single cylinder free piston engine according to an embodiment of the present application in a third perspective.

Reference numerals:

1-piston, 101-piston head, 102-piston tail, 103-inner hole, 104-wedge structure, 105-vent, 106-top dead center signal tooth, 107-bottom dead center signal tooth, 2-guide shaft, 201-sensor, 3-permanent magnet, 4-spring, 5-coil, 6-motor housing, 7-base, 701-air inlet valve, 8-cylinder, 801-air inlet channel, 802-exhaust channel, 803-cylinder head, 804-fuel injector, 805-spark plug, 806-stiffener, 807-channel, 9-direct current generator.

Detailed Description

The following description of the embodiments of the present application will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the application are shown.

The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the application, as presented in the figures, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application.

All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

A single cylinder free piston engine and method of operation thereof according to some embodiments of the present application are described below with reference to fig. 1-9.

Referring to fig. 1 to 4, an embodiment of the present application provides a single cylinder free piston engine comprising: a cylinder 8, a motor housing 6, a base 7, a piston motion assembly and a coil 5;

Wherein, one end of the motor shell 6 is provided with a base 7, the other end of the motor shell 6 is connected with a cylinder body 8, and the coil 5 is positioned on the inner wall of the motor shell 6; a channel 807 is arranged in the cylinder 8, and the channel 807 is communicated with the inside of the motor housing 6 to form a movement cavity;

the piston motion assembly comprises a guide shaft 2, a piston 1, a permanent magnet 3 and a spring 4; the guide shaft 2 is positioned in the motor shell 6, and one end of the guide shaft 2 is connected with the base 7; the permanent magnet 3 is connected with the piston 1, and the piston 1 is sleeved on the guide shaft 2; the piston 1 can drive the permanent magnet 3 to reciprocate in the motion cavity along the axial direction of the guide shaft 2 and is used for cutting the magnetic induction line of the coil 5; the spring 4 is also sleeved on the guide shaft 2, one end of the spring 4 is connected with the base 7, and the other end of the spring 4 is connected with the piston 1 through the spring 4 base;

An air inlet valve 701 is arranged on the base 7, an air inlet channel 801 is arranged on the cylinder body 8, and the air inlet valve 701 is communicated with the air inlet channel 801 through a movement cavity.

The application provides a single cylinder free piston engine, comprising: a cylinder 8, a motor housing 6, a base 7, a piston motion assembly and a coil 5; one end of the motor shell 6 is provided with a base 7, and the base 7 and the motor shell 6 can be connected through screws; the other end of the motor shell 6 is connected with a cylinder body 8, and the coil 5 is positioned on the inner wall of the motor shell 6; a channel 807 is arranged in the cylinder 8, the channel 807 is communicated with the inside of the motor housing 6 to form a movement cavity, and the piston 1 component is positioned in the movement space and can move along the axial direction of the movement cavity, so that the magnetic induction line of the coil 5 is cut; the dc generator 9 is integrated outside the motor housing 6, so that the permanent magnet 3 can generate electricity when cutting the induction lines.

Specifically, the piston motion assembly comprises a guide shaft 2, a piston 1, a permanent magnet 3 and a spring 4, wherein the guide shaft 2 is arranged along the axial direction of the motion cavity, the piston 1 is fixedly connected with the permanent magnet 3, and the piston 1 is sleeved on the guide shaft 2 to drive the permanent magnet to move along the guide shaft 2; the guide shaft 2 plays a role in guiding the movement of the piston 1 and the permanent magnet 3, so that the piston 1 can reciprocate between the channel 807 of the cylinder 8 and the motor housing 6 along a fixed direction, no offset and the like occur, and the magnetic induction line cutting process is more stable. And a spring 4 is arranged between the piston 1 and the base 7, and the spring 4 is used for pushing the piston 1 to make the piston reciprocate.

In addition, an air inlet valve 701 is further arranged on the base 7, an air inlet channel 801 is formed on the cylinder body 8, the air inlet channel 801 is communicated with the movement cavity, therefore, air entering the motor housing 6 through the air inlet valve 701 enters the air inlet channel 801 of the cylinder body 8 through a gap between the coil 5 and the permanent magnet 3, and then enters a channel 807 of the cylinder body 8 from the air inlet channel 801 of the cylinder body 8, the channel 807 of the cylinder body 8 serves as a combustion chamber, air is mixed with air injection and ignited to burn in the channel 807, and accordingly pushing force is given to the piston 1, and the piston 1 can reciprocate.

The single-cylinder free piston engine of the embodiment of the application has the following specific working processes: the air inlet valve 701 opens the air inlet, and the air enters the channel 807 of the cylinder 8 through the gap between the interior of the engine shell and the permanent magnet 3 and the coil 5 group; referring to fig. 2, the coil 5 of the engine is reversely electrified, so that the coil 5 generates a magnetic field opposite to the permanent magnet 3, the permanent magnet 3 and the piston 1 are pushed to move towards the end of the base 7 along the guide shaft 2 under the repulsive force of the reverse magnetic field, the spring 4 is compressed, and the piston 1 reaches the first position; referring to fig. 3 and 4, the fuel injector 804 injects fuel into the passage 807 of the cylinder 8; the compressed spring 4 generates pushing force to the permanent magnet 3 and the piston 1, the permanent magnet 3 and the piston 1 are pushed to move towards the end of the cylinder body 8 along the guide shaft 2, and the piston 1 reaches a second position; igniting the igniter, burning gas and oil in the combustion chamber, pushing the permanent magnet 3 and the piston 1 to move towards the end of the base 7 along the guide shaft 2 again by generated smoke, compressing the spring 4, enabling the piston 1 to reach the first position, and injecting oil by the oil injector 804; the compressed spring 4 pushes the permanent magnet 3 and the piston 1 to move towards the end of the cylinder body 8 along the guide shaft 2 again, the piston 1 reaches the second position, and the igniter ignites; the permanent magnet 3 and the piston 1 reciprocate between the first position and the second position, the oil injection and ignition processes are repeated, and the permanent magnet 3 cuts the magnetic induction line of the coil 5 to generate electricity, so that continuous electricity generation is realized.

In conclusion, the single-cylinder free piston engine disclosed by the application adopts a mature and simple two-stroke working principle, has the advantages of small volume, light weight, high mechanical efficiency, small energy conversion loss, low self-starting and vibration, low maintenance cost and the like, and effectively improves the endurance mileage of the whole vehicle driving motor.

In one embodiment of the present application, preferably, as shown in fig. 1 to 4, a cylinder cover 803 is disposed at one end of the cylinder body 8 away from the motor housing 6, and an oil injector 804 and an ignition plug 805 are embedded on the cylinder cover 803;

an injector 804 is used to inject fuel into the passage 807 and a spark plug 805 is used to ignite a mixture of oil and air disposed in the passage 807.

In this embodiment, cylinder block 8 is provided with a cylinder head 803 at the end remote from motor housing 6, and cylinder head 803 is arranged such that cylinder block 8 passage 807 is closed, i.e. cylinder block 8 passage 807 and cylinder head 803 together enclose a combustion chamber in which oil and gas are mixed and combusted. The cylinder cover 803 is embedded with an oil sprayer 804 and a spark plug 805, oil mist is sprayed into the combustion chamber through the oil sprayer 804, and the oil mist is mixed with air entering the combustion chamber and is ignited through the spark plug 805, so that the generated instant explosion force pushes the piston 1 to move in a direction away from the cylinder body 8.

Preferably, the cylinder 8 is connected to the housing of the direct current generator 9 by four bolts, and the base 7 is connected to the housing of the direct current generator 9 by four bolts.

In one embodiment of the present application, preferably, referring to fig. 2 to 4, an exhaust passage 802 is further provided on the cylinder block 8, one end of the exhaust passage 802 communicates with a passage 807 of the cylinder block 8, and the other end of the exhaust passage 802 communicates with the outside.

In this embodiment, an exhaust passage 802 is further disposed on the cylinder 8, one end of the exhaust passage 802 is communicated with a channel 807 of the cylinder 8, and the other end of the exhaust passage 802 is communicated with the outside, so that on one hand, exhaust gas after combustion in the channel 807 can be discharged through the exhaust passage 802, so as to realize continuous oil-gas mixing and combustion process in the channel 807; on the other hand, the gas in the passage 807 of the cylinder 8 can enter the inside of the cylinder 8 through the exhaust passage 802, thereby being able to cool the cylinder 8. Therefore, the cylinder body 8 of the single-cylinder free piston engine is integrated with the air inlet channel 801 and the air outlet channel 802, so that the full combustion of oil gas in the channel 807 can be ensured, and the air cooling of the engine can be realized.

Preferably, the air inlet end of the exhaust passage 802 is close to the permanent magnet 3, the outlet end of the exhaust passage 802 is far away from the permanent magnet 3, and the reinforcing ribs 806 are arranged outside the cylinder body 8, so that the air cooling can be effectively realized in the engine from which air is introduced, the direction of the exhaust passage 802 is far away from the permanent magnet 3, and the reinforcing ribs 806 adopt temperature field heat dissipation arrangement.

Therefore, the single-cylinder free piston engine has the advantages of small volume, high integration, effective and reliable strength, heat dissipation function and no need of structures such as a cooling water jacket, a main oil duct structure and the like.

In one embodiment of the present application, preferably, the intake valve 701 is a one-way valve, as shown in fig. 2-4.

In this embodiment, air enters the motor housing 6 through the air inlet valve 701, enters the air inlet channel 801 of the cylinder 8 through the gap between the permanent magnet 3 and the coil 5, and enters the channel 807 of the cylinder 8 through the air inlet channel 801 to be mixed with oil gas and burned. The air inlet valve 701 is a one-way valve, which can effectively avoid air backflow of the piston 1 in the reciprocating motion process, and ensure the working reliability of the single-cylinder free piston engine.

The inner cavity of the single-cylinder free piston engine is closed, the air inlet one-way valve is the only air inlet, the negative pressure one-way valve in the cavity is opened, and the positive pressure one-way valve in the cavity is closed. Specifically, referring to fig. 2, when the piston 1 is compressed and moves up to the top dead center, that is, when the piston 1 is located at the second position, the cavity is under negative pressure, and the check valve opens the intake; referring to fig. 3 and4, when the piston 1 is working down, the air in the cavity starts to be compressed to positive pressure, and the check valve is closed. In the process, fresh air at the tail part can pass through a gap between the permanent magnet 3 and the coil 5, so that the cooling effect is achieved. When the piston 1 descends to the air inlet, positive pressure air in the cavity is extruded into the combustion chamber, and short negative pressure starts to enter from the one-way valve due to the siphon effect of exhaust. The piston 1 moves upwards to pass through the air inlet, negative pressure is generated again in the cavity, air starts to enter from the one-way valve, the reciprocating circulation is performed in this way, the permanent magnet 3 and the coil 5 are cooled by continuous fresh air, and the exhaust direction is far away from the permanent magnet 3. And, in this process, the working stroke exhaust gas (heat) is guided to the engine head, and the heat is away from the dc generator 9 to contribute to the power generation efficiency.

Preferably, the single cylinder free piston engine further comprises an air flow sensor 201, the air flow sensor 201 being connected to the air intake valve 701 (not shown in the figure), the air flow sensor 201 being adapted to detect the intake opening of the air intake valve 701 and the end of the intake.

In one embodiment of the present application, preferably, as shown in fig. 5 to 7 and 9, the piston 1 has a stepped shaft-like structure with one end being a head and the other end being a tail; the head can extend into the engine block 8;

the head 101 of the piston is provided with a wedge structure 104 for swirling the gas in the engine block 8.

In this embodiment, the piston 1 has a stepped shaft-like structure, one end of which is a head portion and one end of which is a tail portion, the head portion of which faces the engine block 8, and the head portion of which can extend into the engine block 8; the tail 102 of the piston faces away from the engine cylinder 8, the axial direction of the piston 1 is consistent with the direction of a channel 807 of the engine cylinder 8, and the piston 1 can extend into the cylinder 8 and then move away from the cylinder 8 in a reciprocating manner under the action of combustion smoke in the cylinder 8. The permanent magnet 3 is sleeved outside one end of the piston 1 close to the tail part and fixedly connected with the piston 1, and the permanent magnet 3 abuts against the step part of the piston 1, so that the installation boundary of the permanent magnet 3 is limited.

Referring to fig. 9, the head 101 of the piston is provided with a wedge structure 104, and the head of the piston 1 can extend into the engine cylinder 8 during the reciprocating motion process of the piston 1, so that when the head of the piston 1 extends into the engine cylinder 8, the wedge structure 104 at the end of the piston can guide the gas entering the cylinder and generate vortex in the cylinder 8, thereby improving the speed of especially mixing in the cylinder 8, meeting the requirement of the oil-gas mixing speed, and further improving the combustion efficiency.

In one embodiment of the present application, as shown in fig. 7 and 8, preferably, an inner hole 103 is provided in the piston 1 along the axial direction thereof, the inner hole 103 penetrates through the tail 102 of the piston, and the piston 1 is sleeved on the guide shaft 2 through the inner hole 103;

the inner hole 103 of the piston 1 and the section of the guide shaft 2 are of peach-shaped cam structures, and the inner hole 103 of the piston 1 is matched with the guide shaft 2.

In this embodiment, an inner bore 103 is provided in the piston 1 in its axial direction, the inner bore 103 extending through the tail 102 of the piston; one end of the guide shaft 2 is fixed with the base 7, the other end of the guide shaft 2 extends into the inner hole 103 through the tail 102 of the piston, the axial direction of the guide shaft 2 and the axial direction of the piston 1 are on the same straight line, the guide shaft 2 can play a guide role on the movement of the piston 1, and the piston 1 can reciprocate along the axial direction of the fixed guide shaft 2.

In order to avoid the piston 1 from rotating around the guide shaft 2 in the process of reciprocating motion, the inner hole 103 of the piston 1 is in a peach-shaped cam shape along the section perpendicular to the axis of the inner hole 103; the guide shaft 2 has a peach-shaped cam-shaped structure in a section perpendicular to the axis, and the inner hole 103 of the piston 1 is matched with the shape and the size of the guide shaft 2. Because the diameters from the center to the edge of the peach-shaped cam-shaped structure are different, the piston 1 cannot rotate in the reciprocating motion process, and therefore the permanent magnet 3 can be driven to cut the magnetic induction line more stably to generate electricity.

In one embodiment of the application, preferably, as shown in fig. 2 to 4, the guide shaft 2 is provided with a sensor 201 near the tail of the piston 1, and the piston 1 is provided with signal teeth.

In this embodiment, in order to clearly determine the position of the piston 1 during movement and thus to better control the injection and ignition timing, the single cylinder free engine piston 1 of the present application is embedded with a sensor 201 on the guide shaft 2, the position of the sensor 201 being at the end of the guide shaft 2 remote from the base 7, i.e. the end of the guide shaft 2 near the tail of the piston 1 when the head 101 of the piston extends into the engine block 8. The piston 1 is correspondingly provided with signal teeth, and the signal teeth can provide position signals for the sensor 201 of the piston 1 in the process of reciprocating the piston 1 along the guide shaft 2, and after knowing the position signals, the air inlet time, the oil injection time and the ignition time of the engine can be controlled more accurately.

Specifically, the sensor 201 is a position sensor, and the sensor 201 is embedded on the guide shaft 2, so that the structure is simplified without bolt installation, the stability of the obtained signal is better, the service life is longer, and the sensor is suitable for a free piston type internal combustion engine.

Preferably, the signal teeth are rectangular holes, namely rectangular through holes are formed in the piston 1, and the sensor 201 detects the positions of the rectangular holes in the moving process of the piston 1, so that the positions of the piston 1 are judged, and basis is provided for oil injection and ignition.

In one embodiment of the present application, preferably, as shown in fig. 2 to 4 and 6, the signal teeth include top dead center signal teeth 106 and bottom dead center signal teeth 107, the top dead center signal teeth 106 are disposed at the head 101 of the piston, and the bottom dead center signal teeth 107 are disposed between the head 101 and the tail of the piston;

The number of the top dead center signal teeth 106 is one, the number of the bottom dead center signal teeth 107 is two, and the line connecting the positions of the top dead center signal teeth 106 and the two bottom dead center signal teeth 107 is parallel to the axis of the piston 1.

In this embodiment, according to the reciprocating motion locus of the piston 1, the top dead center signal teeth 106 and the bottom dead center signal teeth 107 are provided on the piston 1; the top dead center signal tooth 106 is a first rectangular hole, which is correspondingly located at the head 101 of the piston, when the sensor 201 detects a pulse signal at the top dead center, that is, the position of the piston 1 is known to be the second position, at this time, the head 101 of the piston stretches into the engine cylinder 8, the head 101 of the piston corresponds to the position of the sensor 201 of the guide shaft 2, and at this time, the sensor 201 recognizes ignition.

The bottom dead center signal teeth 107 are second rectangular holes, the number of the second rectangular holes is at least two, the second rectangular holes are correspondingly positioned in the middle of the piston 1, when the sensor 201 detects pulse signals corresponding to the number of the second rectangular holes at the bottom dead center, the position of the piston 1 is known to be the first position, the head 101 of the piston stretches out of the cylinder 8, the tail 102 of the piston is close to the shell of the engine, the spring 4 is compressed, and the sensor 201 recognizes that the piston 1 is finished in working.

When the piston 1 moves in the opposite direction to the position close to the cylinder 8 under the action of the spring 4, the sensor 201 receives a plurality of pulse signals again, and at this time, the sensor 201 recognizes the oil injection signal and delays oil injection.

The piston 1 continues to move until the sensor 201 detects a pulse signal again at the top dead center, namely, the position of the piston 1 is known to be a second position, and ignition is identified; the above-described process is repeated to complete the continuous detection and identification process of the sensor 201.

Therefore, the single cylinder free engine piston 1 of the present application can accurately determine the ignition timing by providing the position sensor. While conventional internal combustion engine ignition is based on a crankshaft position sensor and a camshaft position sensor to confirm ignition timing, free piston 1 engine has no crankshaft rotation mechanism, no valve mechanism, and conventional crankshaft position sensor arrangement scheme cannot be adopted for ignition, if ignition timing cannot be accurately confirmed, single cylinder piston 1 can strike cylinder head 803. In the application, the sensor 201 is embedded in the guide shaft 2, and the rectangular hole is correspondingly formed in the piston 1, so that the sensor 201 can effectively identify the position of the top dead center of the piston 1, and provides a basis for oil injection ignition.

Preferably, as shown in fig. 7, the number of bottom dead center signal teeth 107 is two, and the sensor 201 can detect two continuous pulse signals at the bottom dead center of the piston 1, so as to identify that the working is finished; when the piston 1 is operating in reverse, the sensor 201 can again detect two successive pulse signals, identifying the injection signal. By providing two rectangular holes at the bottom dead center signal teeth 107, it is distinguished from the top dead center signal, thereby more accurately determining the positional information of the piston 1 and controlling ignition.

In addition, the connecting line of the positions of the top dead center signal tooth 106 and the two bottom dead center signal teeth 107 is parallel to the axis of the piston 1, that is, the length, width and height dimensions of each rectangular hole on the long axis of the piston 1 are consistent, but the arrangement positions are different, and the accuracy of the signal detection of the sensor 201 can be ensured because the piston 1 does not rotate in the process of reciprocating motion.

In one embodiment of the present application, preferably, referring to fig. 6 and 7, a vent hole 105 is formed on the piston 1, and the vent hole 105 is communicated with the inner hole 103; the number of the vent holes 105 is plural, and the plurality of vent holes 105 are uniformly provided in the circumferential direction of the piston 1.

In this embodiment, the piston 1 is provided with the vent hole 105, and the vent hole 105 is communicated with the inner hole 103 of the piston 1, so as to balance the air pressure inside and outside the piston 1, avoid the plunger effect generated in the piston 1 during the reciprocating motion of the piston 1, and increase unnecessary oil consumption, thereby improving the thermal efficiency of the engine.

Preferably, the piston 1 is provided with a plurality of vent holes 105, the vent holes 105 are uniformly distributed along the circumferential direction of the piston 1, and the effect of balancing the internal and external air pressure of the piston 1 is better.

Still more preferably, the number of the vent holes 105 is 8, and 8 vent holes 105 are located at the middle position of the piston 1.

The embodiment of the application also provides a working method of the single-cylinder free piston engine, which is shown in fig. 2 to 4 and comprises the following steps:

Step 100, opening air inlet through a one-way valve, wherein the air enters a channel 807 of the cylinder body 8 through gaps inside the engine shell and between the permanent magnet 3 and the coil 5;

Step 200, reversely electrifying a coil 5 of an engine, so that the coil 5 generates a magnetic field opposite to the permanent magnet 3, pushing the permanent magnet 3 and the piston 1 to move towards the end of the base 7 along the guide shaft 2 under the repulsive force of the reverse magnetic field, compressing a spring 4, and enabling the piston 1 to reach a first position; the sensor 201 in the piston 1 detects the bottom dead center position signal and controls the oil injector 804 to inject oil into the channel 807 of the cylinder 8;

Step 300, the compressed spring 4 generates pushing force to the permanent magnet 3 and the piston 1, the permanent magnet 3 and the piston 1 are pushed to move towards the end of the cylinder body 8 along the guide shaft 2, and the piston 1 reaches a second position; the sensor 201 in the piston 1 detects a top dead center position signal, the igniter is controlled to ignite, gas and oil in the channel 807 are combusted, generated smoke pushes the permanent magnet 3 and the piston 1 to move towards the end of the base 7 along the guide shaft 2 again, the spring 4 is compressed, the piston 1 reaches a first position, and the fuel injector 804 injects fuel; the compressed spring 4 pushes the permanent magnet 3 and the piston 1 to move towards the end of the cylinder body 8 along the guide shaft 2 again, the piston 1 reaches the second position, and the igniter ignites;

Step 400, the permanent magnet 3 and the piston 1 reciprocate between the first position and the second position, the oil injection and ignition processes are repeated, and the permanent magnet 3 cuts the coil 5 to magnetically induce the line to generate electricity, so that continuous electricity generation is realized.

In summary, the single cylinder free piston engine of the present application has the following advantages:

1. The self-starting, the compression working is carried out through the magnetic fields opposite to the magnetic field bodies and the magnetic fields repel each other, the variable intercept spring 4 is stressed in the working stroke, and the variable intercept spring 4 provides a reaction force to push the piston 1 to move upwards to carry out the compression working condition at the end of the working stroke, so that the piston is reciprocated;

2. The design of a crankshaft connecting rod mechanism is canceled, a piston 1 assembly is arranged, wherein the piston 1 is designed by adopting a long shaft, the long shaft is in a ladder shape, the tail part of the long shaft is provided with a base 7, the base 7 and a ladder-structure shaft are used for fixing the permanent magnet 3 groups, and the long shaft of the piston 1 is provided with a vent 105, so that the plunger effect generated in the reciprocating motion of the piston 1 can be avoided;

3. the peach-shaped cam guide shaft 2 can ensure that the piston 1 does not rotate in the reciprocating process;

4. The air is fed from a one-way valve at the bottom of the engine (naturally aspirated), and after passing through the one-way valve, the air passes through a gap generated by the permanent magnet 3 and the coil 5 and is finally extruded into a combustion chamber in the compression process (the one-way valve is closed), and the temperature of the piston 1 is reduced by continuously feeding fresh air into the permanent magnet 3 and the coil 5; the engine cylinder body 8 is integrated with the air inlet channel 801 and the air outlet channel 802, and the periphery of the engine cylinder body is provided with a reinforcing rib 806 structure, so that the reinforcing rib 806 has strong heat dissipation capacity, the air cooling of the engine can be realized, the fuel consumption is reduced, and the heat efficiency is improved; no lubricating oil is used for lubrication, so that the fuel consumption is reduced;

5. the integrated direct current generator 9 cuts the magnetic induction line to generate electricity;

6. and the direct injection in the cylinder reduces the oil consumption and improves the heat efficiency.

Therefore, the single-cylinder free piston engine adopts the mature and simple two-stroke working principle, has the advantages of unique and ingenious air inlet design, small volume, light weight, high mechanical efficiency, small energy conversion loss, self-starting, no need of lubricating oil for cooling and lubrication, small vibration, low maintenance cost and the like, and effectively improves the endurance mileage of the whole vehicle driving motor.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims (4)

1. A single cylinder free piston engine comprising: the device comprises a cylinder body, a motor shell, a base, a piston motion assembly and a coil;

The motor comprises a motor shell, a cylinder body, a coil, a base, a motor and a coil, wherein the base is arranged at one end of the motor shell, the other end of the motor shell is connected with the cylinder body, and the coil is positioned on the inner wall of the motor shell; a channel is arranged in the cylinder body and is communicated with the inside of the motor shell to form a movement cavity;

The piston motion assembly comprises a guide shaft, a piston, a permanent magnet and a spring; the guide shaft is positioned in the motor shell, and one end of the guide shaft is connected with the base; the permanent magnet is connected with the piston, and the piston is sleeved on the guide shaft; the piston can drive the permanent magnet to reciprocate in the motion cavity along the axial direction of the guide shaft and is used for cutting the magnetic induction line of the coil; the spring is also sleeved on the guide shaft, one end of the spring is connected with the base, and the other end of the spring is connected with the piston through a spring seat;

An air inlet valve is arranged on the base, the air inlet valve is a one-way valve, an air inlet channel is arranged on the cylinder body, the air inlet valve is communicated with the air inlet channel through the motion cavity, so that air entering the motor shell through the air inlet valve under the negative pressure action of the motion cavity enters the air inlet channel of the cylinder body through a gap between the coil and the permanent magnet, and then enters the channel of the cylinder body from the air inlet channel of the cylinder body, and the channel is used as a combustion chamber;

An exhaust passage is further arranged on the cylinder body, one end of the exhaust passage is communicated with a passage of the cylinder body, and the other end of the exhaust passage is communicated with the outside;

The piston is of a stepped shaft structure, one end of the piston is a head part, and the other end of the piston is a tail part; the head can extend into the engine cylinder;

the head of the piston is provided with a wedge-shaped structure for enabling gas in the engine cylinder body to generate vortex;

The position of the guide shaft, which is close to the tail part of the piston, is provided with a sensor, and the piston is provided with signal teeth;

The signal teeth comprise top dead center signal teeth and bottom dead center signal teeth, the top dead center signal teeth are arranged at the tail part of the piston, and the bottom dead center signal teeth are arranged between the head part and the tail part of the piston;

the number of the top dead center signal teeth is one, the number of the bottom dead center signal teeth is two, and the connecting line of the positions of the top dead center signal teeth and the two bottom dead center signal teeth is parallel to the axis of the piston;

An inner hole is formed in the piston along the axial direction of the piston, the inner hole penetrates through the tail of the piston, the piston is sleeved on the guide shaft through the inner hole, a vent hole is formed in the piston, and the vent hole is communicated with the inner hole; the number of the vent holes is a plurality of, and the vent holes are uniformly arranged along the circumferential direction of the piston.

2. The single cylinder free piston engine of claim 1 wherein a cylinder head is provided at an end of the cylinder body remote from the motor housing, the cylinder head having an injector and spark plug embedded therein;

the fuel injector is used for injecting fuel into the passage, and the spark plug is used for igniting a mixture of oil and air placed in the passage.

3. The single cylinder free piston engine of claim 1 wherein,

The piston is of a peach-shaped cam-shaped structure with the cross section of the guide shaft, and the piston is matched with the guide shaft.

4. A method of operating a single cylinder free piston engine according to any one of claims 1-3, comprising the steps of:

The one-way valve opens the air intake, and the air enters the channel of the cylinder body through the gap between the permanent magnet and the coil assembly and the inside of the engine shell;

Simultaneously, the coil of the engine is reversely electrified, so that a magnetic field opposite to the permanent magnet is generated by the coil, the permanent magnet and the piston are pushed to move along the guide axial base end under the repulsive force of the reverse magnetic field, the spring is compressed, and the piston reaches the first position; a sensor in the piston detects a bottom dead center position signal and controls an oil injector to inject oil into a channel of the cylinder body;

The compressed spring generates pushing force to the permanent magnet and the piston to push the permanent magnet and the piston to move along the guide axial cylinder end, and the piston reaches a second position; the sensor in the piston detects a top dead center position signal, the igniter is controlled to ignite, gas and oil in the channel are combusted, generated smoke pushes the permanent magnet and the piston to move along the guide axial base end again, the spring is compressed, the piston reaches a first position, and the oil injector injects oil; the compression pushes the permanent magnet and the piston to move along the guide axial cylinder end again, the piston reaches a second position, and the igniter ignites;

The permanent magnet and the piston reciprocate between the first position and the second position, the oil spraying and ignition processes are repeated, and the permanent magnet cuts the magnetic induction line of the coil to generate electricity, so that continuous electricity generation is realized.