5.3.3. Gas-distributing mechanism
The engine has two paths: inlet and final.
Inlet path
The inlet path consists of the inlet pipe cast from aluminum alloy. The inlet pipe through paronitovy laying by five hairpins fastens to a head of the block of cylinders on the right.
From above in a middle part of an inlet pipe there is a platform to which through laying on four hairpins of M8 the carburetor fastens.
From below under the carburetor the inlet pipe has a shirt for its heating. The shirt is closed by the cover cast from aluminum alloy and fixed to an inlet pipe through laying by five bolts of M6. Two unions for a supply and removal of liquid of heating are screwed in a cover.
Heating of an inlet pipe is carried out by cooling liquid which is brought from a shirt of the block of cylinders and is taken away in the pump of cooling liquid through rubber hoses.
On the vertical platform the valve of recirculation of the fulfilled gases is fixed in a middle part of an inlet pipe through laying on two hairpins. Will screw the thermal vacuum switch in a wall of a shirt of an inlet pipe.
Besides, two unions for selection of depression to the sensor of absolute pressure and to the vacuum amplifier of brakes are screwed in an inlet pipe.
Final collector
The final collector is cast from cast iron and through four steel laying by eight hairpins fastens to a head of the block of cylinders at the left.
For improvement of cleaning of cylinders of the engine of the fulfilled gases and increase in its power indicators branch pipes of a final collector from the first and fourth, and also from the second and third cylinders are in pairs connected among themselves.
Will screw the union for a supply of a part of the fulfilled gases to the recirculation valve in a final collector.
Camshafts
Camshafts are cast from cast iron. The engine has two camshafts: for inlet and final valves. Profiles of cams of camshafts identical. For achievement of high wear resistance the working surface of cams is bleached to high hardness when casting the camshaft.
Each shaft has five basic necks. The first neck has diameter of 42 mm, the others — 35 mm. Shaft rotate in the support formed by an aluminum head and aluminum covers, chiseled assembled.
Cams on width are displaced on 1 mm concerning an axis of hydraulic pushers that during the operation of the engine gives to a pusher rotary motion. As a result of it wear of an end face of a pusher and opening under a pusher decreases and does it uniform.
Each camshaft refrains from axial movements by the persistent steel thermostrengthened or plastic flange which enters bore of a cover of a forward support and a pro-point on a forward basic neck of the camshaft. Camshafts provide the following phases of gas distribution: inlet valves open with an advancing on 14 ° before arrival of the piston to VMT, are closed with delay on 46 ° after arrival of the piston to NMT, final valves open with an advancing 46 ° before arrival of the piston to NMT and are closed with delay on 14 ° after arrival of the piston to VMT. The specified phases of gas distribution are valid at the correct installation of the drive of camshafts. Height of raising of valves — 9 mm.
Drive of camshafts
Fig. 4.118. Drive of camshafts: 1 — an asterisk of a bent shaft; 2 — a gidronatyazhitel of the lower chain; 3 — a shumoizolirushchy rubber washer; 4 — a stopper; 5 — a boot of a gidronatyazhitel of the lower chain; 6 — the lower chain; 7 — the conducted asterisk of an intermediate shaft; 8 — the leading asterisk of an intermediate shaft; 9 — a boot of a gidronatyazhitel of the top chain; 10 — a gidronatyazhitel of the top chain; 11 — the top chain; 12 — an adjusting tag on an asterisk; 13 — an adjusting pin; 14 — an asterisk of the camshaft of inlet valves; 15 — the top uspokoitel of a chain; 16 — an asterisk of the camshaft of final valves; 17 — the top plane of a head of the block of cylinders; 18 — an average uspokoitel of a chain; 19 — the lower uspokoitel of a chain; 20 — a chain cover; Ml and Sq.m — adjusting tags on the block of cylinders
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The drive of camshafts (fig. 4.118) — chain, two-level. The first step — from a bent shaft on an intermediate shaft, the second step — from an intermediate shaft on camshafts.
The driving chain of the first step (lower) has 70 links, the second step (top) — 90 links. The chain is vtulochny, two-row with a step of 9,525 mm.
On cranked to a shaft there is an asterisk 1 of high-strength cast iron with 23 teeths. On intermediate to a shaft there is a conducted asterisk 7 first steps also from high-strength cast iron with 38 teeths and the leading steel asterisk 8 second steps with 19 teeths. On camshafts asterisks 14 and 16 of high-strength cast iron with 23 teeths are established. The asterisk on distributive to a shaft is established on a forward flange and an adjusting pin and fastens the central bolt of M 12u1,25. Camshafts rotate twice more slowly than cranked.
At end faces of an asterisk of a cranked shaft, the conducted asterisk of an intermediate shaft and asterisks of camshafts there are adjusting tags serving for the correct installation of camshafts and providing the set gas distribution phases.
The tension of each chain (lower 6 and top 11) is made automatically — gidronatyazhitel 2 and 10. Are established to Gidronatyazhiteli in the chiseled openings: lower — in a cover of a chain 20, top — in a head of the block of cylinders — are also closed by the aluminum covers fixed on a cover of a chain and to a head of cylinders by two bolts of M8 through paronitovy laying.
The case of a gidronatyazhitel through a noise-insulating rubber washer 3 rests against a cover, and the plunger through a boot affects a non-working branch of a chain. Besides, in a cover there is an opening with a conic carving K 1/8", closed by a stopper 4 through which the gidronatyazhitel "is discharged".
Boots are made of plastic with a curvilinear working surface and with steel basic platforms on which press plungers of gidronatyazhitel.
Boots 5 and 9 are established konsolno on the axes screwed in a forward end face of the block of cylinders.
Working branches of chains pass through the uspokoitel 15, 18 and 19 made of plastic and fixed by two bolts of M8 everyone: lower 19 — at a forward end face of the block of cylinders, top 15 and average 18 — at a forward end face of a head of the block of cylinders.
Gidronatyazhitel
Fig. 4.119. Gidronatyazhitel assembled: 1 — the valve assembled; 2 — a locking ring; 3 — a plunger; 4 — the case; 5 — a spring; 6 — a lock ring
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Gidronatyazhitel (fig. 4.119) — steel, is executed in the form of plunger couple consisting of the case 4 and a plunger 3. In a plunger the spring 5 which is compressed by the valve 1 case with an external carving in which the backpressure ball valve is located is established. The case 4 and a plunger 3 are connected among themselves via the ratchet device consisting of a locking ring 2, ring flutes in the case and flutes of a special profile on a plunger. Gidronatyazhitel is established on the engine in the "loaded" state when the plunger 3 keeps in the case 4 by means of a lock ring 6.
In working order the gidronatyazhitel "is discharged" when the lock ring 6 is brought out of a flute in the case and does not hold a plunger.
Gidronatyazhitel works as follows. Under the influence of a spring 5 and pressure of the oil arriving from the oil highway the plunger 3 presses a chain boot, and through it — a chain. In process of an extract of a chain and wear of a boot the plunger moves forward from the case 4, moving a locking ring 2 ratchet devices from one flute of the case in another. At change of high-speed power setting and emergence of blows from a chain on a boot the plunger 3 moves back, squeezing a spring 5; at the same time the ball valve is closed and there is an additional damping at the expense of an oil overflowing through a gap between a plunger and the case.
Reverse motion of a plunger is limited to flute width on a plunger.
Intermediate shaft
Fig. 4.120. Intermediate shaft: 1 — a bolt; 2 — a lock plate; 3 — the leading asterisk; 4 — the conducted asterisk; 5 — the forward plug of a shaft; 6 — an intermediate shaft; 7 — a pipe of an intermediate shaft; 8 — the conducted gear wheel of the drive of the oil pump; 9 — a nut; 10 — the leading gear wheel of the drive of the oil pump; 11 — the back plug of a shaft; 12 — the block of cylinders; 13 — a flange of an intermediate shaft; 14 — a pin
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The intermediate shaft (fig. 4.120) — steel, two-basic, is established in inflows of the block of cylinders, on the right. An external surface of a shaft of an uglerodoazotirovan on depth of 0,2 — 0,7 mm and a termoobrabotan.
The intermediate shaft rotates in the plugs pressed in openings in inflows of the block of cylinders. Forward 5 and back 11th plugs steel-aluminum.
The intermediate shaft refrains from axial movements by a steel flange 13 which is located between an end face of a forward neck of a shaft and a nave of the conducted asterisk 4 with a gap of 0,05 — 0,2 mm and is fixed by two bolts of M8 to a forward end face of the block of cylinders.
The axial gap is provided with a difference of the sizes between ledge length on a shaft and flange thickness. For increase in wear resistance the flange is tempered, and for improvement extra earnings face surfaces of a flange of a shlifovana and a fosfatirovana.
On a forward cylindrical ledge of a shaft the conducted asterisk 4 is established. The leading asterisk is established by the 3rd cylindrical ledge in an opening of the conducted asterisk 4, and its angular situation is fixed by the pin 14 pressed in a nave of the conducted asterisk 4. Both asterisks "напроход" fasten two bolts 1 (M8) to an intermediate shaft. Bolts kontritsya by bending on their side of corners of a lock plate 2.
On a shaft of an intermediate shaft by means of a spline and a nut 9 the leading kosozuby gear wheel of the 10th drive of the oil pump is fixed.
The free surface of an intermediate shaft (between basic necks) is hermetically closed by the thin-walled steel pipe 7 pressed in inflows of the block of cylinders.
Fig. 4.121. Drive of valves: 1 — the inlet valve; 2 — a head of cylinders; 3 — the camshaft of inlet valves; 4 — a plate of valve springs; 5 — an oil scraper cap; 6 — an external spring of the valve; 7 — the camshaft of final valves; 8 — a hydropusher; 9 — a valve cracker; 10 — the final valve; 11 — an internal spring of the valve; 12 — a basic washer of springs of the valve
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Valves are given from camshafts directly through hydraulic pushers of 8 (fig. 4.121) for which the directing openings in a head of the block of cylinders are executed.
The drive of valves is closed from above by the cover cast from aluminum alloy with the labyrinth maslootrazhatel fixed from the inside with three maslootvodyashchy rubber tubes. The cover of valves through rubber laying and rubber a sealant of candle wells fastens to a head of the block of cylinders eight bolts with a diameter of 8 mm.
From above on a cover of valves the cover of a maslozalivny opening and two coils of ignition are established.
Valves
Valves are manufactured from heat resisting staly: the inlet valve — from chromosiliceous, final is manufactured of hromonikelmargantsovisty steel and nitrated. On a working facet of the final valve heat-resistant chromonickel alloy is built in addition up.
Diameter of a core of valves — 8 mm. The plate of the inlet valve has diameter of 37 mm, and final — 31,5 mm. A corner of a working facet of both valves — 45 ° 30'. On the end of a core of the valve pro-points for crackers of the 9th plate of 4 springs of the valve are executed. Plates of springs of valves and crackers are made of low-carbonaceous steel and subjected to superficial nitrocementation.
On each valve about two springs are established: external 6 with the right navivka and internal 11 — with left. Springs are made of thermally processed high-strength wire and subjected to bead-blasting processing. Under springs the basic steel washer 12 is established. Valves 1 and 10 work in the directing plugs manufactured of gray cast iron. The internal opening of plugs is finally processed after their press fitting in a head. Plugs of valves are supplied with the lock rings interfering spontaneous movement of plugs in a head.
For reduction of amount of the oil passing through gaps between the plug and a core of the valve by the top ends of all plugs of a napressovana the oil scraper caps 5 made of oilproof rubber.
Details of the valvate mechanism: valves, springs, plates, crackers, basic washers and oil scraper caps — are interchanged with similar details of the engine of the VAZ-2108 car.
Hydropusher
Fig. 4.122. Hydropusher: 1 — the directing compensator plug; 2 — the hydropusher case; 3 — a lock ring; 4 — the compensator case; 5 — the compensator piston; 6 — the backpressure ball valve; 7 — a spring
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The hydropusher — steel, its case 2 (fig. 4.122) is executed in the form of a cylindrical glass in which the compensator with the return ball the valve is placed. On the external surface of the case the flute and an opening for an oil supply in a pusher are executed from the highway in a head of cylinders. For increase in wear resistance an external surface and an end face of the case of a pusher of a nitrotsementirovana.
Hydropushers are established in the openings with a diameter of 35 mm chiseled in a head of cylinders between end faces of valves and cams of camshafts.
The compensator is placed in the directing plug 1 installed and welded in the hydropusher case and is kept by a lock ring 3. The compensator consists of the piston 5 leaning from within on a bottom of the case of a hydropusher, the case 4 which leans on a valve end face. Between the piston and the case of the compensator the spring 7 which is moving apart them and by that choosing the arising gap is established. At the same time the spring 7 presses a cap of the backpressure ball valve 6 placed in the piston. The backpressure ball valve passes oil from a hydropusher case cavity in a cavity of the compensator and locks this cavity when pressing a cam of the camshaft the hydropusher case.
The hydropusher as follows works: when pressing a cam of the camshaft an end face of the case of a gidrotodkatel 2 (opening of the valve) the ball valve 6 is closed, locking the oil which is in the compensator; at the same time oil becomes a working body through which the effort and the movement from a cam to the valve is transmitted.
At the same time a part of oil flows through a gap in plunger pair of the compensator in a cavity of the case of a hydropusher and the piston 5 is a little moved into the compensator 4 case.
When closing the valve when the effort from a hydropusher is removed, the spring of the 7th compensator presses the piston 5 and the case 2 hydropushers to a cylindrical part of a cam ("nape"), choosing a gap, at the same time the ball valve 6 in the compensator opens, letting in oil then the cycle is repeated a compensator cavity.
Hydropushers automatically provide bezzazorny contact of cams of camshafts with valves, compensating iznosa of the interfaced details: cams, end faces of the case of a hydropusher, case of the compensator, valve, facets of saddles and plates of valves.
On long not working cold engine emergence of knock of hydropushers which has to disappear in process of warming up of the engine up to the working temperature (80 — 105 °C) is possible.
If after 30 min. after launch of the engine the knock does not disappear, it is necessary to check supply of oil to a hydropusher or to replace a faulty hydropusher.