RU2516767C1 - Plunger-free four-cylinder engine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed engine comprises housing, two pairs of opposed cylinders and two sets of pistons. Magnetically permeable insert is arranged between said cylinders. Every piston set is composed of a single assembly with two ends and cylindrical hollow housing. Said magnetically permeable insert is arranged at mid part of the latter. Inside of said housing permanent segment-shape magnets are arranged. Engine housing has the clearance between magnetically permeable cylindrical insert and internal magnetically permeable cylindrical insert At least one excitation coil is fitted there outside. Piston sets are displaced in opposite directions by timing gear. Said timing gear is composed by bell crank. Proposed engine comprises control unit. Pressure gage is fitted in every cylinder electrically connected with control unit.

EFFECT: lower vibration, higher power output.

3 cl, 4 dwg

Description

The invention relates to internal combustion engines, specifically to free piston engines.

Known free piston engine according to the USSR AS No. 985365, MKI 5 F02B 71/04, publ. 12.30.82, containing a diesel internal combustion engine, a linear generator and a fuel supply system. The engine is a cylinder with end combustion chambers, in the area of which there are intake and exhaust valves. Inside the cylinder there are pistons connected by a jumper (rod).

The generator consists of a stator, an armature and excitation and load relieving systems. The stator is made in the form of stator windings and field windings. These windings are mounted on the outer surface of the cylinder. The anchor is made in the form of current collector and field windings, which are laid inside the pistons and connected to each other in series. The excitation system is made in the form of connecting excitation terminals, and the load shedding system is made in the form of load shedding terminals.

The fuel supply system is a nozzle located in the end parts of the cylinder and designed to supply fuel to the combustion chamber.

The energy conversion process is divided into two main cycles: the first cycle is the conversion of energy from the chemical energy of the fuel into the mechanical energy of the movement of the pistons, and the second - the mechanical energy of the movement of the pistons is converted into electrical energy. The first cycle is the workflow of a two-stroke diesel engine, and the second, in turn, is divided into two stages. At the first stage, by crossing the winding of the first piston of the magnetic field created by the first stator winding (field winding), a magnetic field is excited in the first piston. At the second stage, the formation and removal of electricity occurs, and the winding of the first piston plays the role of the field winding for the second piston.

Using the principle of electromagnets in both parts of the linear generator allows you to get a high power magnetic field and, as a result, minimize the size of the installation.

However, the known device has the following disadvantages. When the device is operating, the movement of one piston is used to excite a magnetic field in another. This leads to the loss of the working process of the first piston to produce energy for current collection. Incomplete use of a two-stroke diesel engine workflow to generate energy for current collection is the cause of low efficiency. In addition, from overheating of the windings to a temperature of 500-600 ° C, their magnetic properties are reduced, which also reduces the efficiency of the motor.

Known free piston engine according to the USSR AS No. 1733650, MKI 5 F02B 71/04, publ. 05/15/92 g, consisting of a diesel internal combustion engine, a linear generator, a fuel supply system and a cooling system.

This engine comprises a cylinder with exhaust valves in the end parts of the engine and a purge window in the central part of the engine. Inside the sleeve is a piston with a rod.

The generator consists of a stator, an armature, an excitation system and a load lifting system. The stator is made in the form of windings mounted on the outer surface of the cylinder. An anchor is a winding laid inside a piston. The excitation system is made of brushes and excitation wires. Brushes are located inside the piston. They are the first part of the sliding contact of the excitation system with the armature winding. The second part of the sliding contact is the excitation current receiving plate located on the armature winding. The plate is connected to the terminals of the armature winding. The excitation supply wires are located in the stock.

The fuel supply system includes two nozzles located in the opposed parts of the cylinder. The cooling system consists of two water nozzles, also located in the opposite parts of the cylinder.

Energy conversion is carried out in the same way as in the above engine, and consists of two cycles: the first cycle is the conversion of energy from the chemical energy of the fuel into the mechanical energy of the movement of the pistons, the second - the mechanical energy of the movement of the pistons is converted into electrical energy. The first cycle is a two-stroke diesel engine workflow. The second cycle, unlike the above engine, consists of one stage and represents the working process of a linear generator with direct excitation. The exception of one stage is achieved thanks to the direct excitation system, the wires of which pass through the rod.

The principle of operation of the cooling system is that when a certain temperature of the exhaust gases is reached (600-800 ° C), coolant is supplied to the combustion chamber through special water nozzles, which, evaporating and mixing with the exhaust gases, forms a cooling medium that cools the combustion chamber . The cooling system reduces the temperature of the exhaust gases to 100-200 ° C. But the temperature of the cooled exhaust gases is still lower than the temperature of the piston and armature winding, because first, the exhaust gases are cooled, and then they remove the excess heat from the piston and winding. Because of this, the temperature of the piston and windings decreases only to 250-300 ° C.

The advantage of this engine is an increase in efficiency due to the full use of the working process of a two-stroke engine for the production of electricity for current collection. In addition, the efficiency is increased by reducing the magnetic field loss due to a decrease in the temperature of the windings (in particular the armature windings).

However, the known device has the following disadvantages. The lack of direct contact of the cooling medium with the armature winding located inside the piston leads to insufficient cooling of the winding. The temperature of the winding is reduced only to 250-300 ° C. In this case, the loss of the electromagnetic field on copper windings is 50% greater than the loss of the electromagnetic field at a temperature of 20 ° C.

In addition, the supply of coolant to the combustion chamber leads to sharp changes in temperature, and, as a result, to fluctuations in the magnetic field and the strength of the generated current, which also affects the reduction of efficiency.

Known free piston engine according to the patent of Russian Federation No. 2186231, IPC F02B 71/04, publ. 02/27/2002, the prototype.

This engine contains a diesel internal combustion engine made of a cylinder with nozzles, inside of which there is a piston with a rod, a linear generator made of stator windings located on the cylinder, from an armature winding located on the piston and in contact with an excitation system consisting of brushes with excitation supply wires, a load-lifting system and a cooling system, two additional shut-off rings of the cooling system fixed to the rod and cooling tubes connected to it are additionally introduced into it with an internal piston chamber, while the armature winding is located on the piston rod, each cut-off ring is installed between the winding and the end parts of the piston, and the brushes are installed in the cylinder body.

Disadvantages - low efficiency due to the lack of a system for timely opening and closing of valves and low reliability due to the use of windings and current collectors in explosive atmospheres: oil vapor with fuel. In addition, the GTE launch system has not been developed.

Objectives of the invention: reducing vibration loads and increasing engine power.

The solution of these problems was achieved in a four-cylinder free-piston engine containing an engine block, two pairs of opposed cylinders and two piston groups, in accordance with the invention a magnetically permeable insert is installed between the cylinders, each piston group is made as a single unit with two ends and a cylindrical hollow body, in the middle part of which an internal magnetically permeable cylindrical insert is made, and permanent magnets of a segmented shape are radially mounted inside, to rpus engine is configured to define a gap between a magnetically permeable cylindrical inner insert and a magnetically permeable cylindrical insert, it is installed at least one field winding, and the movement of the piston in opposite directions groups provided matching mechanism. The coordination mechanism can be made in the form of a two-shouldered lever. A four-cylinder free-piston engine may contain a control unit, and in each cylinder a pressure sensor is installed connected by electrical communication with the control unit.

The invention is illustrated in figure 1 ... 4, where:

- figure 1 presents a diagram of the engine,

- figure 2 shows a diagram of a piston group and a pair of opposed cylinders,

- figure 3 shows a section aa,

- figure 4 shows the electrical circuit of the engine.

Free piston engine (figure 1) contains a motor housing 1, two pairs of opposed cylinders 2 ... 5 and two piston groups 6 and 7. A magnetically permeable insert 8 is installed between the cylinders 2 ... 5. The shape of the insert 8 is rectangular or rectangular with rounded corners. In this case, the piston groups 6 and 7 are made in the form of a single unit with two ends 9 and 10 and a cylindrical hollow body 11, in the middle part of which an internal magneto-permeable insert 12 is installed and permanent magnets 13 are radially mounted. The motor housing 1 is made with the formation of a cavity 14 between the magneto-permeable insert 8 and an inner cylindrical insert of magnetically permeable material. The material of magnetically permeable inserts 8 and 12 is titanium, stainless steel, polymer, composite material and other materials permeable to magnetic fields. The motor housing 1 is connected to the cylinders 2 ... 5 by flanges 15. Outside relative to the magnetically permeable insert 8, at least one field winding 16. is installed. Field winding 16 is an integral part of a linear electric generator.

On both sides of the piston group 6 has compression and oil scraper rings, respectively 17 and 18 (figure 2).

A feature of the proposed four-cylinder free-piston engine is that it synchronizes the operation of the piston groups in such a way that the piston groups move in opposite directions. The synchronization of the movement of several pistons in the internal combustion engine is widely used and carried out by a crankshaft. In free piston engines, the crankshaft is absent, and synchronizing the operation of piston groups is a difficult technical task.

The synchronization mechanism 19 (figure 1 ... 3) is made in the form of a two-shouldered lever 20 mounted on an axis 21 passing through an opening 22 made in the middle part of this lever. At the ends of the two shoulders of the lever 20, open rectangular grooves 23 are made through which the fingers 24 are installed, installed in the piston groups 6 and 7 for press fit in the inner housings 25 of the piston groups 6 and 7 (Fig. 3).

In addition, the engine contains intake manifolds 26 and a common intake manifold 27, as well as exhaust manifolds 28 and a common exhaust manifold 29. Fuel injectors 30 and an intake valve 31 with an actuator 32 are installed in the intake manifolds 26. Exhaust valves 33 s are installed in the exhaust manifolds 28. drives 34. In each cylinder 2 ... 5 there is an electric candle 35.

The engine may contain a control unit 36, and in each cylinder 2 ... 5 there is a pressure sensor 37 connected by electrical connection 38 to the control unit 36. The engine may include a piston position sensor 39 installed on each cylinder 2 ... 5 connected by electrical connection 38 to the block control 36 (figure 4).

The field winding 16 is connected by electric wires 40 to a switch 41. The switch 41 by electric wires 40 is connected to a battery 42 and an electric motor 43.

On the engine casing 1, a filling hole 44 is made, connected by an oil pipe 45 containing a valve 46 with an oil tank 47.

The engine fuel system comprises a fuel tank 48 to which a fuel line 49 is connected, comprising a fuel pump 50 connected to the fuel nozzles 30. An electrical diagram of the engine is shown in FIG. 3 and 4.

The operation of the free piston engine (figure 1 ... 4) is as follows.

To start the engine, the voltage from the battery 42 through the switch 41 is supplied to the common field winding 16. In this case, the linear generator operates as a motor. At the same time, the control unit 36 includes a fuel pump 50 and fuel from the fuel tank 48 is supplied to the fuel nozzles 30. Then, the inlet valve 31 of one of the cylinders 3 is opened by applying a signal from the control unit 36 to the actuator 32 and the fuel-air mixture enters the cavity of one of the cylinders 2 or 3. During the operation of the free piston engine (FIGS. 1 ... 4), each stroke of the piston group 6 is a working stroke for one of the cylinders 2 ... 5, while for the opposite part this stroke is a compression process. Upon reaching the necessary degree of compression detected by the pressure sensor 37 and / or the piston position sensor 39, the control unit 36 supplies voltage to the electric candle 35. The piston group 6 makes a stroke. The piston group 7 moves in the opposite direction due to the synchronization mechanism 19. Then, the exhaust valve 33 is opened by issuing a command from the control unit 36 to the actuator 34. An exhaust occurs.

Then a similar cycle is repeated in other cylinders 3 ... 5.

The temperature of the piston group 6 and 7 due to their contact with hot exhaust gases, will be at the maximum mode no more than 500-600 ° C.

When the engine stops, the linear generator switches back to engine mode and the fuel supply is turned off (not shown). In this case, in order to counteract the movement of the piston, the stop current supplied to the linear electric generator can provide movement of the piston group 6 in the direction opposite to the actual direction of motion of the piston group 6 for emergency braking.

Because during the operation of the free piston engine, the temperature in the field winding 16 of the linear electric generator, which is located outside the cylinders 2 ... 5, is approximately +10 - + 20 ° C, then the magnetic field losses in the copper windings for heating are reduced in comparison with the magnetic field losses in prototype 30-50%. Reducing losses leads to increased efficiency of the free piston engine. The absence of current collectors leads to increased fire safety, and the absence of windings in the high temperature zone increases the reliability of the engine.

The synchronization mechanism reduces vibration loads due to the opposite movement of the piston groups and increases the engine power due to a sharper change in the magnetic flux through the excitation winding.

A reliable lubrication system allows you to increase the life of the engine before overhaul, reduce wear of the rubbing parts and prevent overheating.

The electronic control system allows you to fully automate the process of ignition and opening and closing the drain and exhaust valves and adjust their opening and closing, depending on the engine operating mode.

Improving the environmental friendliness of the engine, as the vehicle in densely populated areas can move with the free piston engine off on the battery.

The use of pressure sensors and piston positions on both cylinders allows not only to open and close the intake and exhaust valves and supply voltage to the electric candles in a timely manner, but also to control the emergency situation and, if necessary, automatically turn off the engine.

The invention allows to expand the range of production of free piston engines with one or two or more blocks based on one developed and brought module.

Claims (3)

1. Four-cylinder free-piston engine containing an engine casing, two pairs of opposed cylinders and two piston groups, characterized in that a magnetically permeable insert is installed between the cylinders, each piston group is made as a single unit with two ends and a cylindrical hollow body, in the middle of which an internal magnetically-permeable cylindrical insert is made, and permanent magnets of a segmental shape are radially mounted inside, the engine housing is formed with the formation of a gap ra between magnetically permeable cylindrical inner insert and a magnetically permeable cylindrical insert, it is installed at least one field winding, and the movement of the piston in opposite directions groups provided matching mechanism. 2. The four-cylinder free-piston engine according to claim 1, characterized in that the matching mechanism is made in the form of a two-shouldered lever. 3. The four-cylinder free-piston engine according to claim 1 or 2, characterized in that it contains a control unit, and in each cylinder there is a pressure sensor connected by electrical communication with the control unit.

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