CZ35538U1 - Engine with lossless lubrication system - Google Patents

Description

Engine with lossless lubrication system

Field of technology

The technical solution concerns a two-stroke engine equipped with a set of elements enabling its lossless lubrication.

State of the art

Solutions are known which cause lossy engine lubrication, where oil is mixed into petrol in a conventional two-stroke engine or in more modern supercharged Achates two-stroke engines with counter-rotating pistons. Their disadvantage compared to the technical solution proposed here is the need for turbocharging, higher production complexity, the need for a multi-cylinder concept, which requires at least 3 cylinders to run, and also the unsuitability of use on smaller and lighter vehicles.

The essence of the technical solution

The essence of the technical solution is a two-stroke engine with lossless lubrication, which does not have to be equipped with supercharging. The new lubrication system according to this technical solution makes it possible to use the space under the pistons to suck air into the engine and at the same time to pressurize the oil sump, which will allow the oil to be transported to the engine without the use of a pump. This lubrication system allows much lower oil degradation by flue gases. The version of the engine with counter-rotating pistons has higher efficiency and lower fuel consumption compared to modern four-stroke engines and is simpler to manufacture.

The engine lubrication system according to this technical solution includes the use of the following elements, which are described below.

The piston rings which pass through the channels in the cylinder must have anti-rotation locks, ie wiper and sealing. So that their joint is in a place where it will not pass through the channels in the cylinder by the movement of the piston.

The sealing ring is above the wiper ring (not shown in the drawings).

The cylinder has a layer of nickel or similar surface treatment on the surface. It is suitable to provide the piston with a surface treatment reducing friction, so that there are no large friction losses at the outlets of the channels. These points are not lubricated and may be 0.06 mm smaller in diameter than the lubricated points on the piston. Unlubricated to smaller diameter points on the piston begin 1 to 2 millimeters behind the oblique grooves 22.

The crankshafts are interconnected by four gears. The ones directly on the crankshaft are smaller and should have internal shock absorption. The two middle wheels are larger, which allows for slow gearing, with one of them driving the transmission via a clutch.

The engine is single-cylinder with two pistons. The multi-cylinder solution is more complicated with regard to the location of the channels in the axis of the piston pin. It is advantageous if the motor is supra-square with an ideal bore of approx. 80 mm. The stroke of each piston is 90 mm. The engine is designed as a low speed for maximum efficiency.

Longer overflow channels protrude from the crankshaft space at the top, as the exhaust ducts must be avoided, the ducts j being two on either side of the cylinder and j being narrow in order to avoid a large loss of overpressure. All channels are paired. Long overflow channels open into

- 1 CZ 35538 UI of short overflow channels of the second crankcase. And they then enter the cylinder in the axis of the piston pin. One piston controls (overlaps) the overflow channels, the other the exhaust channels.

The coolant is fed to the cylinder on the side where the exhaust ducts are located and discharged on the other side where the overflow ducts are.

Disadvantages of such a lubricated engine include the higher weight of the pistons due to their large length. However, their inertial force is hampered by compression pressures below and above the piston. The disadvantage is the greater production complexity.

On the contrary, the advantage is the high efficiency of the engine. Thanks to the design with counter-rotating pistons, the working time is twice as long, which is reflected in excellent thermal efficiency. The performance of one cylinder is comparable to a four-stroke four-cylinder with twice the cylinder capacity, while achieving half the fuel consumption.

Description of details of the technical solution, which are not shown in the drawings:

The most widespread way of driving cars so far, the four-stroke engine, will have a harder time dealing with increasingly stringent emission standards in the future. The solution may be an engine with counter-rotating pistons, which is currently being developed by several manufacturers. Their engines are usually supercharged three-cylinder, which are not very suitable for smaller and cheaper vehicles.

In order to achieve the highest possible overpressure, the free space around the crankshafts must be kept to a minimum. The crankshaft is round with drilled balancing holes clogged with cork or other suitable lightweight material. This solution also reduces the swirl of the intake air.

The weight of the crankshafts should be higher so that the engine idling speed can be reduced even at a higher compression ratio. Its optimum value, calculated from the stroke of both pistons with the channels closed, is 1:11. Too high a compression ratio will allow the engine to work with a leaner mixture, but the engine then has to wash its own compressions at low speeds and the engine runs coarser, which is undesirable for a single cylinder.

It is not necessary to equip the motor with balancing shafts. Its solution itself eliminates vibrations.

The two-stroke non-supercharged engine with counter-rotating pistons with a new lossless lubrication system is suitable for driving motor vehicles.

The engine according to this technical solution equipped with the lubrication system described here does not require supercharging, it is smaller, simpler and, most importantly, significantly more economical than the existing four-stroke four-cylinder.

The essence of this technical solution therefore lies in the fact that the engine is provided with the lossless lubrication system proposed here, which is characterized by a new way of draining oil from the piston by a drain pump, the presence of an overpressure oil sump and oil distribution to the engine by this overpressure. Furthermore, this system comprises oil grooves and channels in the pistons, the function of which is evident from the accompanying drawings, which also include the engine itself (see Fig. 1).

The present technical solution makes it possible to build a two-stroke engine with counter-rotating pistons with lossless lubrication, the efficiency of which, if properly designed, will be the highest among current internal combustion engines. By combining this drive with an auxiliary electric drive, which would solve journeys in municipalities, convoys, parking and the like, fuel consumption is further reduced.

Description of the function of individual elements of the device:

• Overpressure oil sump 1:

The overpressure in the oil sump ensures that the oil is transported to the engine. An oil pump is not necessary.

- 2 GB 35538 UI • Discharge channels 2 with oil line to the engine:

Through the pipe from the bottom of the tank, the oil is pushed through the center of the crankshaft into the drilled channels in the flywheels, into the center of the main connecting rod pins and further through the drilled hole in the connecting rods into the grooves in the connecting rod, and finally through the drilled channels in the piston into the lubrication grooves on the piston. The rotation of the crankshafts increases the lubrication pressure compared to the pressure in the oil sump.

• Oil filter 3:

Mounted from the outside under the upper edge of the oil pan.

• Check valve 4:

It contributes to faster transport of oil to the engine immediately after starting the engine and prevents aeration of the collection pump when the engine is switched off.

• Oil pan pressure hose 5:

These can be hydraulic hoses and can return even a small amount of oil to the bath in the event of increased engine wear. They enter the oil bath at its highest point above the oil level.

• Check valves 6:

They are low-resistance, ie with a soft spring, they prevent the pressure in the oil pan from pulsating during start-up and low engine speeds, thus contributing to more efficient lubrication. In one of them, a small hole with a diameter of 1 mm is drilled to equalize the pressure between the tub and the spaces under the pistons when the engine is switched off, which prevents possible oil penetration into the channels in the cylinder when the engine is switched off.

• Wiper rings 7:

They wipe the oil into the lubrication groove 23 below each other - this groove is not milled around the entire circumference of the piston, but only on the most loaded surfaces - perpendicular to the piston axis - so as not to interfere with the channels in the cylinder. This prevents oil from entering the combustion chamber. All ducts (overflow and exhaust) open into the cylinder from the side - in the axis of the pin. The sloping groove 22 prevents oil from penetrating the channels from the side. The piston ring has an anti-rotation lock designed so that its joint does not pass through the channels.

• Slip rings 8:

Prevents oil from penetrating under the piston.

• Oil collecting grooves 9 in the cylinder:

They discharge the oil from the collecting drain groove 19 on the piston to the collecting oil pump 13. There are two circumferential oil channels to each piston in the cylinder. They are placed at an angle 1800 to each other at the location of the collecting drain groove 19 on the piston, from which they suck up the oil by moving the piston along its entire length.

• Reed suction valve 10:

The engine air intake flap is on both crankcases. One overflow channel is long and the other short. One piston controls the overflow channel. Second piston exhaust duct.

• Fuel injection nozzle 11:

It injects before the top dead center well in advance of the spark plug spark. The fuel can be bioethanol or gasoline. The injection should be high pressure.

• Spark plug 12.

• Collecting oil pump 13:

It draws oil from the four drain channels in the cylinders and pushes it into the oil pan through the oil filter. This entire lubrication circuit works independently and is separated from other oil fillings.

• Upper eye 14 of the connecting rod:

- 3 CZ 35538 UI

The lubrication grooves in the upper connecting rod eye are milled to lubricate the piston pin while draining the oil further into the piston through the grooves 20.

• Sealing rings 15:

The sealing ring is made of a heat-resistant, non-flammable material between the connecting rod and the smooth counter-surface 21 on the piston. There must be a minimum clearance.

• Drilled hole 16 in the center of the connecting rod:

The optimal diameter of the drilled hole in the center of the connecting rod is 7 mm. The hole does not have to be drilled, it can be created by another production method.

• Piston 17.

• Drilled lubrication channels 18:

There are a total of four on the piston. They point from the lubrication grooves 20 in the piston to the lubrication groove 23 under the wiper ring. They are drilled in the inner piston struts.

• Manhole 19:

The groove above the lower slip ring perpendicular to the axis of the pin serves to drain the oil into the slip groove 9 in the cylinder with which it overlaps. On the piston j, two are milled perpendicular to the center of the groove 30 above the collecting ring, into which the oil engages and discharges from it into the collecting groove 9 in the cylinder. The groove does not interfere with the groove 23 under the wiper ring. The distance of the groove 23 under the wiper ring 8 from the lower slip ring is longer than the stroke of the piston, so that the slip groove 9 in the cylinder does not get too close to the groove 23 under the wiper ring at the bottom dead center.

• Lubrication groove 20 in the piston in the direction of the pin axis:

Its length does not exceed the length of the piston pin - the pin is then blinded at the side wall of the piston by a cover, which never reaches the level of the channels with its entire surface.

• Straight smooth counter-surface 21 of the sealing ring in the connecting rod eye:

It fits snugly against the side of the connecting rod eye with the sealing ring 15.

• Oblique groove 22 on the piston surface:

A shallow groove (1 mm) with a special wiper tip shape is guided obliquely along the piston wall from the upper wiper ring to the lower slip groove above the slip ring. Their wiper tip draws oil away from the channels in the cylinder. The grooves are guided outside the overflow and exhaust ducts and do not interfere with the movement of the pistons - they do not overlap. There are four oblique grooves on the piston extending from the wiper ring 7 to the groove 30 above the slip ring. From this ring 7 they do not point downwards perpendicularly, but slightly obliquely. Their shape (shown in Fig. 4c) prevents oil from entering the channels in the cylinder. This is also aided by the vacuum in these grooves, formed by the oil sump.

• Lubrication groove 23 under the wiper ring:

There are two lubrication grooves under the wiper ring on each piston. Each occupies almost 1/3 of the section of the piston circle. The oblique grooves 22 on the piston do not intersect with them. There are no more grooves on the side of the piston at the point of blinding of the piston pin. The overflow and exhaust ducts lead into the cylinder there.

• Plugs for 24 drilled lubrication channels: Used to blind the drilled lubrication holes.

• Sealing sleeve 25:

The sealing sleeve is placed between the connecting rod side and the crankshaft.

- 4 EN 35538 UI • Drilled holes 26 in the center of the main connecting rod:

They are mostly directed towards the piston. In the connecting rod bearing, the lubrication grooves are in the direction of the pin axis only if it is sliding. There is only a minimum clearance between the connecting rod and the crankshaft, and opposing grooves are milled from the side of the connecting rod, which pour oil from the sleeve 25 towards the pin while the engine is running. The connecting rod can also be mounted on the crankshaft by two rows of rollers. So as not to interfere with the bore 16 in the center of the connecting rod and the bores 26 in the pin. The crankshaft axis does not intersect with the cylinder axis, but passes by approx. 9 mm (with a piston stroke of 90 mm). This is because the expansion reduces the angle of the connecting rod relative to the piston. This reduces the lateral pressure of the piston on the cylinder wall and thus increases the engine torque. With a horizontally mounted engine, the crankshafts should rotate in such a direction that the piston is pushed toward the top of the cylinder during expansion and the compression to the bottom of the cylinder when compressed.

• Grooves 27 along the pin:

The grooves along the piston pin drain oil from the connecting rod eye into the drilled channels 18. The grooves in the piston and the connecting rod must be flush with each other at the top and bottom of the piston and the contact surfaces of the grooves have chamfered edges so that the channels do not close .

• Groove 30 above the slip ring:

The shape resembles a groove under the wiper ring - mirror-image. Drains the oil from the sloping grooves into the collecting drain 19.

Clarification of drawings

Giant. 1 shows a section of an engine showing the distribution of oil through a pressurized oil sump;

Giant. 2 shows a part of the engine with drilled lubrication channels and drilled holes in the center of the main connecting rod;

Giant. 3 shows an engine piston in section with oil distribution;

Giant. 4a shows the oil distribution inside the piston and the grooves on the piston surface;

Giant. 4b shows the outlet of the channel into the lubrication groove under the wiper ring;

Giant. 4c shows the shape of an oblique groove on the surface of the piston in cross section;

Giant. 4d shows the oil drain channel from the cylinder.

Examples of technical solutions

Example 1

Engine with a lossless lubrication system, comprising one cylinder and two pistons, which includes:

- an overpressure oil sump 1 to ensure the transport of oil to the engine by means of an overpressure;

- oil discharge channels 2 to the engine, which are connected to the sump 1 and pass into the center of the crankshaft and further into the flywheels and the center of the main connecting rod pins;

- non-return valves 6 provided with a soft spring to achieve low resistance and to prevent pressure pulsation in the oil sump, where at least one flap 6 comprises a 1 mm diameter hole serving to equalize the pressure between the sump and the spaces under the pistons when the engine is switched off;

- oil collecting grooves 9 in the cylinder for draining oil from the collecting drain groove 19 on the piston to the collecting oil pump 13;

- a collecting oil pump 13 for pumping oil from the collecting grooves 9;

- sealing rings 15 made of heat-resistant, non-flammable material and placed between the connecting rod and the smooth counter-surface 21 on the piston;

a hole 16 in the center of the connecting rod, the diameter of which is preferably 7 mm;

drilled lubrication channels 18, where each piston comprises exactly four channels, these channels 18 extending from the lubrication grooves 20 in the piston to the lubrication groove 23 below the wiper ring and being drilled in the inner struts of the pistons 17;

- 5 CZ 35538 UI

- a collecting gutter 19 formed above the lower collecting ring perpendicular to the axis of the pin serving to drain the oil into the collecting groove 9 in the cylinder with which it overlaps, two grooves 19 being milled perpendicular to the center of the groove 30 above the collecting ring. they engage and discharge oil from it into the collecting groove 9 in the cylinder, the groove not interfering with the groove 23 under the wiper ring and the distance of the groove 23 under the wiper ring 8 from the lower collecting ring being longer than the stroke of the piston;

- lubrication grooves 20 in the piston in the direction of the axis of the pin, the length of which does not exceed the length of the piston pin, which is blinded at the side wall of the piston 17 by a cover which does not reach the channel level with its entire surface;

- inclined grooves 22 on the surface of the piston in the form of a wiper tip and guided obliquely along the wall of the piston 17 from the upper wiper ring to the lower collecting groove above the slip ring, the wiper tip being shaped to draw oil away from the channels in the cylinder and the grooves 2 the overflow and exhaust ducts do not interfere with or overlap by the movement of the pistons, there being four oblique grooves on one piston extending from the wiper ring 7 to the groove 30 above the slip ring and not downwards perpendicularly but slightly obliquely from this ring 7;

- lubrication grooves 23 under the wiper ring, where on each piston 17 there are two lubrication grooves under the wiper ring and each occupies almost 1/3 of the section of the piston ring 17, the oblique grooves 22 on the piston not intersecting with them;

- drilled holes 26 in the center of the main connecting rod pin, the axis of the crankshafts not intersecting with the axis of the cylinder, but passing to achieve a reduction in the lateral pressure of the piston on the cylinder wall;

- grooves 27 along the piston pin for draining oil from the connecting rod eye into the drilled channels 18, the grooves 27 in the piston and the connecting rod being flush with each other at the upper and lower dead ends of the piston 17 and the contact surfaces of the grooves 27 having chamfered edges so they do not close the channels against the piston 17;

- grooves 30 above the collecting ring for draining oil from the oblique grooves into the collecting drain groove 19.

Example 2

A variant of an engine provided with a lossless lubrication system according to Example 1, wherein the engine is a two-stroke single-cylinder and a single-piston engine with a higher cylinder volume for driving various machines.

Industrial applicability

The technical solution of a two-stroke engine equipped with a lossless lubrication system is industrially applicable especially for the propulsion of vehicles and machines.

Claims (1)

PROTECTION REQUIREMENTS A lossless lubrication system comprising one cylinder and two pistons, characterized in that the lossless lubrication system consists of passing oil from an overpressure oil sump (1) through discharge channels (2) and through connecting rods (16) to the upper eye ( 14) a connecting rod, where it further enters the piston (17) and cylinders, being further discharged by means of collecting circumferential grooves (19) on the piston and collecting grooves (9) in the cylinder to the collecting oil pump (13) and through the oil filter and non-return valve (4) enters back into the pressure vessel (1), the engine comprising: an overpressure oil sump (1) for transporting oil to the engine by overpressure; oil discharge lines (2) to the engine, which are connected to the sump (1) and pass into the center of the crankshaft and further into the flywheels and the center of the main connecting rod pins; non-return valves (6) provided with a soft spring to achieve low resistance and to prevent pressure pulsation in the oil sump, wherein the at least one flap (6) comprises a 1 mm diameter hole for equalizing the pressure between the sump and the spaces under the pistons when the engine is switched off; oil collecting grooves (9) in the cylinder for draining oil from the collecting drain groove (19) on the piston to the collecting oil pump (13); a collecting oil pump (13) for pumping oil from the collecting groove (9); sealing rings (15) made of heat-resistant, non-flammable material and placed between the connecting rod and the smooth counter-surface (21) on the piston; a hole (16) in the center of the connecting rod, the diameter of which is preferably 7 mm; drilled lubrication channels (18), where each piston contains exactly four channels, these channels (18) leading from the lubrication grooves (20) in the piston to the lubrication groove (23) under the wiper ring and being drilled in the inner struts of the pistons (17) ; a collecting gutter (19) formed above the lower collecting ring perpendicular to the axis of the pin serving to drain the oil into the collecting groove (9) in the cylinder with which it overlaps, two grooves (19) being milled perpendicular to the center of the groove on the piston (17) (30) above the slip ring into which the oil engages and discharges into the slip groove (9) in the cylinder, the groove not interfering with the groove (23) under the wiper ring and the distance of the groove (23) under the wiper ring (8) from the lower slip rings longer than piston stroke; lubrication grooves (20) in the piston in the direction of the axis of the pin, the length of which does not exceed the length of the piston pin, which is blinded at the side wall of the piston (17) by a cover which does not reach the channel level with its entire surface; oblique grooves (22) on the surface of the piston in the form of a wiper tip and extending obliquely along the piston wall (17) from the upper wiper ring to the lower collecting groove above the slip ring, the wiper tip being shaped to draw oil away from the channels in the cylinder and the groove ( 22) are led outside the overflow and exhaust ducts and do not interfere with or overlap by the movement of the pistons, while on one piston there are four oblique grooves leading from the wiper ring (7) to the groove (30) above the slip ring and do not point from this ring (7) down perpendicular but slightly oblique; lubrication grooves (23) under the wiper ring, where on each piston (17) there are two lubrication grooves under the wiper ring and each occupies almost 1/3 of the section of the piston ring (17), the oblique grooves (22) on the piston not intersecting them; Drilled holes (26) in the center of the main connecting rod pin, the crankshaft axis not intersecting with the cylinder axis, but passing to reduce the lateral pressure of the piston on the cylinder wall; grooves (27) along the piston pin for draining oil from the connecting rod eye to the drilled channels (18), 5 wherein the grooves (27) in both the piston and the connecting rod are in the upper and lower dead ends of the piston (17) facing each other in the plane and contact surfaces of the grooves (27). ) have chamfered edges so that the channels do not close together by turning the connecting rod against the piston (17); grooves (30) above the collecting ring for draining oil from the oblique grooves into the collecting groove (19).