Some years in connection with financial crisis of factory and actual cessation of work over automobile governmental ЗИЛом engineers of bureau are in termless administrative holiday. But they have managed to find application of the professionalism, having created firm on repair of automatic transmissions. Through their hands have passed tens marks and hundred models, so a word - to experts.
Whether it is possible, what is called, "on fingers", to explain a principle of work of an automatic transmission?
I will try. Imagine a usual mechanical box with gear wheels of constant gearing - we will tell, such, as at VAZ-2108. In it steams of gear wheels are in the constant contact, thus conducted freely rotate. Including any transfer, you mechanically block a corresponding gear wheel on conducted to a shaft. In an automatic box, speaking in images, about each gear wheel there is a frictional element which at inclusion fixes it on a shaft by means of forces of a friction. And to exclude jerks in transmission at a gear change, on a place of habitual coupling the hydrotransformer rotating in a casing filled with oil is established. Проскальзывание butter layers, first, демпфирует jerks, and secondly, the additional increase in the transfer relation, in a range from 1 to approximately 2 provides. For clearness we considered the elementary двухвальную a box. So are designed "хондовские" "automatic machines". In automatic boxes of the majority of other marks planetary reducers, as a rule, are used.
There is an opinion that for conditions of Russia automatic boxes do not approach...
The American firms have the selector of an automatic box on a wheel, and a scale of the index of its positions – on the panel of devices more often. The pictogramme "D" in a framework designates "overdrive" – an overdrive gear.
It is necessary to search for its sources, most likely, in usual neglect elementary service regulations and in conviction that any, even it is possible to repair the most difficult unit, having in an active only self-confidence and pair of wrenches. As to our roads the suspension bracket much more suffers from them.
What basic advantages and lacks of an automatic transmission in comparison with the mechanical?
The main advantage - in ease of driving that is especially convenient, say, in a city with its stoppers. It is enough to remove a foot from a brake pedal - and the car starts to move. Besides, thanking демпфирующим to properties of the hydrotransformer and absence of rigid mechanical communication between the engine and transmission a resource of the last increases on 20-30 %. A payment for it - higher price and complexity of a design of an automatic box at a little smaller, than at mechanical, a resource and necessity of the qualified service.
What resource of "automatic machine"?
In Europe a traditional place of the selector of "automatic machine" – a floor tunnel.
On the average 150-200 thousand kilometres at competent operation. I mean regular control of level of oil, its replacement together with the filter and "unsportsmanlike" style of driving. The last demands an explanation. At "automatic machine" switching растормаживаются one and затормаживаются other groups of frictional elements. Naturally, the the big capacity is developed by the engine, the more intensively they wear out. For example, at bench tests the automatic box of "the Jeep - of Cheroki" has sustained twelve thousand cycles нагружения, each of which simulated step dispersal with braking at full use of capacity of the engine. It is possible to count up, "automatic machine" how much will suffice "the racer", trying to win each start from a traffic light. At the quiet driver at regular service the box will pass also a half-million of kilometres.
How much with an automatic box dynamic indicators and fuel consumption of the car differ from a variant from the mechanical?
Dynamic indicators and profitability of the car with the automatic machine usually on 5-10 % are worse, than with "mechanics". However, the last does not concern newest "automatic machines": optimisation of computer management does the cars equipped with them even more economically variants with mechanical boxes. Many cars have nowadays compulsory blocking of the transformer - she also allows to lower the expense of gasoline on highway. By the way, some models are equipped by the device interfering transition to the higher transfer if the engine yet has not got warm.
How to estimate a condition of an automatic box at car purchase "from hands"?
As a first approximation it is possible to judge its condition to following signs. In - the first, measured щупом in a box oil level at the working engine should settle down in an admissible range. Deviations in any party can result (if any more have not resulted) in breakages. Secondly, oil should be transparent and, as a rule, red colour. The small suspension well appreciable on a white paper, brown and furthermore black colour of oil testify, at least, to strong deterioration of friction clutches and future repair. Thirdly, it is necessary to glance under the car. Made oily картер boxes - it doesn't matter, short of that it is necessary to add oil continually. Worse if its decrease has not been in due time noticed - with all possible consequences. At last, fourthly, at dispersal automatics should smoothly, without jerks, "touch" all without a transfer exception, up to the higher. If all these conditions are observed, the box in working order and still will serve. In general, as a rule, if to the car more than ten years and its run for two hundred thousand - be ready to repair.
What it is necessary to know to the person who for the first time has sat down for a wheel of the car with an automatic trancemission?
On some models the selector moves in a step groove. It is made for convenience of switching "blindly", to the touch.
To begin with it is necessary to understand designations of modes of its work. Usually their five - six also join they the lever-selector. "Р" - from English "parking" when transmission is separated with the engine, and the target shaft of a box is rigidly blocked. By the way, in order to avoid stopper breakage to include this mode it is possible only by completely motionless car. "R" - "backspacing", a backing. "N" - "neutral" - the same, as "parking", but without blocking of driving wheels." D "or" OD "-" a drive "when the box touches consistently all transfers of a forward course, up to accelerating"overdrive"if that is available. All named modes also are desirable for including by completely braked car. Effective receptions of driving, on film insurgents when the backing in full operation"is stuck"and wheels begin acquaintances with squeal and a smoke to turn in the opposite direction, will reduce life of an automatic box about several minutes. Modes" 3 "," 2 "and" 1 ", sometimes designated by alphabetic symbols, allow to limit a switching range only to corresponding quantity of the lowest transfers. To include them it is possible on the move, for example, in mountains, at towage of the heavy trailer or overcoming a site of bad road. Unique restriction - not to exceed admissible turns of the engine. Selector transfer in position "1" for the speed of 90 km/h, of course, will not give so strong sensations as with "mechanics", but experiences such nevertheless should be avoided.
On some models of cars nearby from the selector there is a small switch with pictogrammes or alphabetic symbols. Most often meeting designations "S", "N", "E", "M" correspond to standard, normal, economic and "mechanical" algorithms of work of "automatic machine". Two first are almost equivalent. Economic allows the engine to work in a range of the least fuel consumption on unit of developed capacity. Near to "Е" the snowflake is sometimes drawn - this mode with moderate enough twisting moment on wheels is good for use in the winter. "The mechanical" range allows to work as the selector, as the lever of the usual, mechanical box equipped with automatic coupling.
Controls of the car with "automatic machine" have one more essential difference: here only two pedals - an accelerator and, unusually wide, brakes. At many drivers using a mechanical box, the most true stereotype of braking was developed steady, though not: by pressing by the right foot a brake left automatically squeezes out coupling. That, having forgotten, not to press both feet on "spacious" pedal of a brake, blocking wheels, at first it is better to hold the left foot more close to a seat.
At the majority of cars with an automatic box the mode "кик даун" when at sharp, to a floor, pressing an accelerator for maintenance of intensive dispersal, there is a compulsory switching on one-two transfers "downwards" is provided. On many modern models such transition occurs at short pressed gas.
What features driving with "automatic machine" has?
Not too it is a lot of them. "Neutral" in usual modes of movement is used seldom enough. For example, moving накатом, the selector is better for leaving in that position in which it was before. Thus the box will pass to higher of the resolved transfers and will provide the minimum braking by the engine. If you slid in a mode "N", the subsequent transition in "D" will force to wait a little with "a gas summer residence" some seconds necessary for an exit of a box on the necessary transfer.
There is an opinion that, standing on a traffic light, it is necessary to pass in "N" as in a mode "D" something there revolves and wears out. Actually it not so, all elements of a box are immobilised, friction clutches the first transfer and only the engine pump empty are clamped, included pumps over oil. Movement in this case begins without proslipping of pairs a friction which enter work only at transition to the second transfer. Transition from a mode "N" in "D" forces them to work once again. On a city trip it is better to exclude the higher transfer, having translated the selector from a range "OD" in "D" or, for lack of "overdrive", from "D" in "3".
It is considered that with "automatic machine" it is heavy to go in the winter. How much обоснованно such opinion?
It not absolutely so. In "regular" modes of enough usual safety measure - softer work as controls. Another matter on a slippery covering, in snow, on sand.
With "mechanics" the moment of the beginning of rotation of wheels and its speed can be supervised precisely enough accelerator and coupling. With "automatic machine" this moment depends only on turns of the engine and to catch it difficult enough. And as resistance of a revolving wheel is less, than motionless, the motor there and then starts it to untwist and the car "is dug in". Thus, as one wheel is usually turned only, because of a hard work the differential can fail. In this case gains knowledge of some receptions. First, it is impossible, by analogy to a mechanical box, to try to "shake" the car is a certain way to ruin a box. Secondly, if be going to move forward, the selector should be in the position corresponding to the most lowest transfer, for example "1". And in - the third, at троганье it is necessary to work as a brake pedal in the same way, as a coupling pedal on the car with a mechanical box. That is, having pressed a brake and having lifted engine turns, smoothly растормаживать wheels, without supposing them раскручивания. By the way, at correctly adjusted brakes this reception plays a role of original blocking of differential.
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