Posted in Useful articles
As a matter of fact, the "scene" is not quite the correct name; in professional literature it is called a thrust for the gearbox control drive. Some novice drivers who have not studied the structure of the car too carefully in a driving school call the lever itself, which switches gears and which is located in the gap between the driver and passenger seats, to be the backstage. You can even read about it on the Internet on not very professional sites.
In fact, the rocker is not even a detail, but a whole structural unit, consisting of several components, which is designed to connect the speed-shifting lever to the rod that is connected directly to the gearbox. It is located under the floor of the car, sometimes even under the bottom, not far from cardan shaft.
The backstage strength resource, determined by manufacturers, is very high and reaches hundreds of thousands of kilometers for some models. However, in the list of failures transmission unit backstage wear does not take last place. If you do not pay attention to the deterioration in the performance of the backstage, problems with the controllability of the machine may soon begin.
Causes accelerated wear, as a rule, act external factors– road dirt or dust that has entered the mechanism, water and corrosion caused by high humidity, as well as untimely lubrication of the moving elements of the backstage. As you can see, the lack of care and Maintenance adversely affects even such simple structural elements as an ordinary backstage.
Backstage device
First of all, you should know that the backstage in different models and brands of cars can be arranged differently, since each company develops its own layout and its own design of many elements, including manual transmission. Yet general principle the actions for all backstage are approximately the same, and having familiarized yourself with the device of one backstage, it is easy to understand how another one works on a different car model.
The backstage in any car usually consists of:
- gearshift lever;
- attached to the thrust lever;
- fork and corresponding finger;
- leak-preemptive transmission fluid gland;
- latch.
It is conditionally possible to classify a cable, a spring and a housing as parts of the backstage. All these parts, connected into a single mechanism, allow you to shift gears in the gearbox, controlling this process from the passenger compartment by means of a lever. The gears are switched strictly in the regulated positions provided for by the design of the gearbox.
How to determine the malfunction of the backstage mechanism
Despite the fact that, according to everyone, the wings are quite robust design and does not require frequent repairs, yet from time to time breakdowns occur in it. Especially it concerns car brands, known for their low quality workmanship and assembly of parts. However, even the German automotive industry, which is considered exemplary in terms of the quality level of automotive equipment production, sometimes allows for the presence of not very reliable backstage, especially in older models with high level wear.
How to understand that the link is faulty, and its operation can lead to an accident? Signs of wear or breakage of the backstage are quite clear. You need to worry and rush to a car service if:
- significantly increased the backlash of the lever that switches speeds;
- gears are switched either with difficulty and interference, or with slipping;
- when shifting one or more gears, a crunch, rattle and other strange sounds are heard;
- gear shifting does not work as it should: when you try to select one gear, another one is engaged, some of the gears cannot be engaged at all, etc.
The occurrence of lever play at first does not bother many drivers, since this defect does not affect the functioning of the car. Quite high prices for maintenance in car services serve as an “argument” in favor of continuing to drive with a faulty backstage: since the car drives and remains controlled, why spend money on diagnosing or repairing it?
But over time, the situation worsens, and at one far from perfect moment, a car in a difficult situation loses control and gets into an accident. The consequences can be different, up to the most severe, when neither the car nor the health can be returned. You should always remember this and respond to the slightest malfunction in the backstage of the car by immediately contacting a specialized service site in Moscow or adjusting the backstage on your own.
How to adjust the yoke?
You can try to adjust the car backstage on their own. Often, it is in the wings that the cause of malfunctions in the operation of the gearbox or clutch lies, and after the defect is eliminated, the state of the machine returns to normal.
- With the engine off, set the lever to first gear. We start the engine and drive to the overpass for repair work.
- We fix the car, preventing an accidental exit: we put it on the handbrake, we put chocks under the wheels.
- Turn off the engine, leave the box in first gear. Then move the gear lever as far to the left as possible. We leave the salon, move under the bottom of the car and tighten the backstage clamp. Sometimes, for a full-fledged adjustment, a displacement of only a few millimeters relative to the driveshaft is enough to restore the gearbox and lever linkage to work.
If the problem does not want to leave your car, contact a specialized service - the masters working there have vast experience in troubleshooting automotive backstage and the MPP as a whole.
3 There is noise in ? The specialists of the car service "Manual transmission repair" will diagnose and fix the breakdown on your car with a guarantee and in a short time.
The mechanical transmission of a car is designed to change the torque and transfer it from the engine to the wheels. It disconnects the engine from the drive wheels of the machine. Let's explain what a manual gearbox consists of - how it works.
The mechanical "box" consists of:- crankcase;
- primary, secondary and intermediate shafts with gears;
- additional shaft and gear reversing;
- synchronizers;
- gear shift mechanism with locking and blocking devices;
- shift lever.
Scheme of work: 1 - input shaft; 2 - switching lever; 3 - switching mechanism; 4 - secondary shaft; 5 - drain plug; 6 - intermediate shaft; 7 - crankcase.
The crankcase contains the main parts of the transmission. It is attached to the clutch housing, which is attached to the engine. Because during operation, the gears are tested heavy loads they should be well lubricated. Therefore, the crankcase is half its volume filled with gear oil.
The shafts rotate in bearings mounted in the crankcase. They have sets of gears with different number teeth.
Synchronizers are necessary for smooth, silent and shockless gear shifting by equalizing the angular velocities of rotating gears.
Switch mechanism serves to change gears in the box and is controlled by the driver using a lever from the passenger compartment. At the same time, the locking device does not allow two gears to be switched on simultaneously, and the blocking device keeps them from being switched off spontaneously.
gearbox requirements
- Ensuring the best traction and fuel-economic properties
- high efficiency
- ease of control
- Shockless switching and quiet operation
- the impossibility of simultaneously engaging two gears or reverse when moving forward
- reliable retention of gears in the engaged position
- simplicity of design and small cost, small size and weight
- ease of maintenance and repair
Ease of control depends on the method of gear shifting and the type of drive. Gears are shifted using moving gears, gear couplings, synchronizers, friction or electromagnetic devices. For shockless switching, synchronizers are installed, which complicate the design, and also increase the size and weight of the transmission. That's why most widespread received those in which top gears they are switched by synchronizers, and the lower ones by gear couplings.
How do gears work?
Let's look at an example of how the torque value (speed) changes in different gears.
a) Gear ratio of one pair of gears
Take two gears and count the number of teeth. The first gear has 20 teeth, and the second 40. So with two revolutions of the first gear, the second will make only one revolution ( gear ratio equals 2).
b) Gear ratio of two gears
On the image b) the first gear (“A”) has 20 teeth, the second (“B”) has 40, the third (“C”) has 20, the fourth (“G”) has 40. Further, simple arithmetic. The input shaft and gear "A" rotate at a speed of 2000 rpm. Gear "B" rotates 2 times slower, i.e. it has 1000 rpm, and since gears "B" and "C" are fixed on the same shaft, then the third gear makes 1000 rpm. Then gear "G" will rotate even 2 times slower - 500 rpm. From the engine to the input shaft comes - 2000 rpm, and comes out - 500 rpm. On the intermediate shaft at this time - 1000 rpm.
IN this example the gear ratio of the first pair of gears is two, the second pair of gears is also two. The total gear ratio of this scheme is 2x2=4. That is, the number of revolutions on the secondary shaft decreases by 4 times, compared with the primary. Please note that if we disengage gears "B" and "G", then the secondary shaft will not rotate. At the same time, the transmission of torque to the driving wheels of the car is also stopped, which corresponds to neutral gear.
Reverse gear, i.e. rotation output shaft On the other side, is provided by an additional, fourth shaft with a reverse gear. An additional shaft is needed to get odd number pairs of gears, then the torque changes direction: 
Power-on torque transmission scheme reverse gear:
1 - input shaft; 2 - gear input shaft; 3 - intermediate shaft; 4 - gear and reverse gear shaft; 5 - secondary shaft.
gear ratios
Since there is a large set of gears in the "box", by engaging different pairs, we have the opportunity to change the general gear ratio. Let's look at the gear ratios:| Transfers | VAZ 2105 | VAZ 2109 |
| I | 3,67 | 3,636 |
| II | 2,10 | 1,95 |
| III | 1,36 | 1,357 |
| IV | 1,00 | 0,941 |
| V | 0,82 | 0,784 |
| R(Reverse) | 3,53 | 3,53 |
Such numbers are obtained by dividing the number of teeth of one gear by the divisible number of teeth of the second and further along the chain. If the gear ratio is equal to one (1.00), then this means that the secondary shaft rotates with the same angular velocity as primary. A gear in which the speed of rotation of the shafts is equalized is usually called - straight. As a rule, this is the fourth. The fifth (or highest) has a gear ratio less than one. It is needed for driving on the highway with minimal engine speeds.
First and reverse gear are the most “strong”. It is not difficult for the engine to turn the wheels, but the car in this case moves slowly. And when driving uphill in the "nimble" fifth and fourth gears, the motor does not have enough strength. Therefore, you have to switch to lower, but "strong" gears.
First gear is required to start moving so that the engine can move a heavy machine. Further, by increasing the speed and making some margin of inertia, you can switch to the second gear, more "weak", but more "fast", then to the third and so on. The usual driving mode - in fourth (in the city) or fifth (on the highway) - they are the fastest and most economical.
What are the faults?
Usually they appear as a result of rough work with the shift lever. If the driver constantly "pulls" the lever, i.e. transfers it from one gear to another with a quick, sharp movement - this will lead to a repair. With this handling of the lever, the switching mechanism or synchronizers will definitely fail.The shift lever shifts in a calm, smooth motion, with micro-pauses in the neutral position for the synchronizers to work, protecting the gears from breakage. With proper handling and periodic oil changes in the "box", it will not break until the end of its service life.
Noise during operation, which depends mainly on the type of gears installed, is significantly reduced when replacing spur gears with helical gears. Correct work also depends on the service on time.
Attending lessons driving skills, you probably remember how much time was devoted to studying the structure of the machine. Basic knowledge is certainly necessary, but in an attempt to fit the course in a short time frame, instructors often forget about, at first glance, not so important issues. Far from everyone can understand the type, functionality and understand the design of such a component as a backstage in a gearbox, due to ignorance of its very existence. Let's try to deal with this device in more detail.
What is a rocker in a gearbox
To begin with, you should figure out what a backstage is, what its functional importance is and why a backstage is needed in a gearbox. Answering the first question, it should be clarified that the exact technical name sounds like "gearbox control rod". In the mistaken assumption of many, it is often referred to as a gear lever. However, rocker gear is a multi-part structure functional purpose which is the linkage of the switch lever with the rod leading to the gearbox.
From this statement it follows that the design of the spare part in itself is sufficient complex mechanism, and the link itself in the gearbox performs the connecting function of the lever with the gearbox. IN modern cars this part is placed under the bottom (close enough to cardan shaft), and in older cars it can be seen directly under the gearbox itself.
Like any other device, the rocker in a manual transmission tends to wear out. The margin of safety of the entire mechanism is often determined by these smallest details, which means that a malfunction of at least one of the components leads to a loss of initial performance. Breakdowns are most often associated with a long service life, hits additional elements into the system (dust, moisture), or insufficient care for the gearbox itself.
A visual diagram of the components of the backstage mechanism: 1 - nut for fastening the base plate; 2 – draft of a drive of management of a transmission; 3 - manhole cover gasket; 4 – a cover of the hatch of the lever of a gear change; 5 – the handle of the gear lever; 6 - gearshift lever; 7 – a cover of the lever of a gear change; 8 - sealing case; 9 - screw securing the hatch cover; 10 - rear support; 11 – the case of the lever of a gear change; 12 – the lower case of the lever of a gear change; 13 - fastening nuts back support; 14 - rear support washer; 15 - nut; 16 - spacer ring; 17 - retaining ring; 18 - body of the ball bearing; 19 – a spring of the lever of a gear change; 20 - ball bearing slider; 21 - nuts for fastening the body of the ball joint; 22 - protective cover; 23 – a tip of draft; 24 - support plate; 25 - gearbox.
Mechanism device
With the current of time automotive manufacturers fundamentally change the features of the checkpoint own machines. New types are constantly emerging robotic boxes gear, special activity enjoy . The progress of the manual transmission also does not stand still, and this desire for modernization often creates a real problem for auto technicians and those who like to delve into their own car.
Thanks to this wide choice available manual transmissions, the design of the backstage itself in the gearbox is subject to constant modification. In order to simplify the task, we use the generalized indicative type of the considered device.
The main components that make up the backstage of the checkpoint:
- gear lever
- Traction gear
- fork + fork finger
- Gland retainer
In addition, conditionally, the backstage includes such components as: a cable, a spring and the body itself (or base). The folded, tuned operation of these parts allows you to switch speed modes in the positions previously assigned to the gearbox.
Backstage symptoms
Despite the excellent reliability of this design, like any other part of a complex working mechanism (during operation, the backstage is subjected to constant physical influences, both from the driver and from the car itself), it requires constant prevention and careful maintenance. Otherwise, undesirable consequences can often occur, leading to breakdowns and problems. Let's analyze the most likely of them:
- looseness of the gear shift knob (lever play has increased);
- difficulty shifting gears (the lever is tight, “crunches” when changing position);
- inability to turn on (for example, turn on 6th gear);
- erroneous switching (instead of the 3rd, the 5th is switched on, etc.).
Unlike the last three, the first problem (backlash) does not affect the shift speed, and generally does not affect the operation of the gearbox. However, what now only causes discomfort can “grow” into serious problems. Delaying repairs in such situations does not lead to anything good, and an unexpected breakdown can happen at the most inopportune moment.
Self adjusting backstage
A common mistake of all novice motorists is to understand their own problem. The slightest malfunction of the gearbox, they associate with global problems and are preparing for a complete replacement of the system. However, it often happens that small interventions, namely the correct and professional adjustment of the backstage, is the necessary solution to eliminate the problem that has arisen.
To begin with, you should start by adjusting (tuning) the drive used. It must be carried out after making sure that it works. At the first speed, we drive onto an overpass, or an elevation of a similar type. If you experience switching problems (described earlier), try necessary actions with the engine off.
Being on handbrake, after substituting the counter-recoils, we begin the preliminary adjustment. With the engine turned off, but the gears not turned off, we shift the lever to the left to the maximum possible position. We tighten the clamp under the car. It often happens that only a few millimeters in relation to the cardan shaft are enough for the necessary displacement.
Another option for the prevention and prevention of problems is to remove foreign elements from the mechanism (moisture, dust, dirt) and lubricate the parts. The rocker in the gearbox, like any other part, requires lubrication. But how to lubricate the backstage? There are no special preferences. Suitable regular lubrication For car parts. The main thing is not to overdo it.
Sometimes a motorist is faced with the question of why the gearshift lever is dangling, but before answering it, you should clearly understand what it is given element Checkpoint, its device and what functions it performs.
Gear lever handle, or what is the design of the system?
feature of all mechanical boxes shifting is the need for manual action on the lever. It can be assumed that it is he who performs essential function in definition speed limit your movement. So, without it, management vehicle becomes simply impossible. The principle of operation of the lever is quite simple: by tilting in the longitudinal and transverse directions, you set it to a position that corresponds to a certain speed.
The gear lever handle is connected to the synchronizer by means of a fork, the position of which conveys information about the number of the selected speed. gearboxes so that the generated engine power allows you to move the car with set speed. In the case when the position of the lever corresponds to the neutral gear, it is held by springs. The shift pattern is often depicted on the head of the lever.
Where is the gear lever positioned?
The location of the gearshift levers can be both on the floor and under the steering wheel. And despite the fact that the latter is considered more convenient to use, nevertheless, in most cases, auto manufacturers prefer the first option. This is due to some disadvantages of the steering column arrangement, including: low speed and clarity, the likelihood of incomplete gear engagement, the rods wear out much faster, sometimes jamming is possible, as well as “knocking out” the gear.
But at the same time, in both versions, the device of the gear lever remains the same. Differences can only be in length, and if earlier it could reach even 30 cm, today manufacturers are striving to make it as small as possible, eliminating too big move gear lever. Therefore, with a floor arrangement, nothing will change significantly in the design, but there will be noticeably less breakdowns.
Squeaking gear lever and other problems
From the foregoing, it is clear that this part is one of the most important in the whole, and if it fails, then driving such a vehicle becomes life-threatening. The most common reasons why such an emergency can occur are either mechanical damage or the consequences of incorrect operation. Here are a few breakdowns that you can easily find yourself.
You should know that the gear lever knob should move freely, without jamming. In the event that there are difficulties in carrying out this action, most likely the spherical washer has failed or spherical bearing. They need to be replaced urgently. The creaking of the gear lever also indicates a malfunction. If it happens spontaneous shutdown, which means that you should definitely check the spring, it is quite possible that it simply jumped off.
How to repair the gear lever?
In any case, whatever happens repair of the gear lever involves the replacement of failed parts, and without it complete withdrawal it would be impossible to do so. For this purpose, the plastic protective plate is dismantled and the hinge cage is released. Then you need to put aside jet thrust and remove the entire lever. But in order to free access to all the plastic bushings and the axle, it is imperative to remove the cover for the gear lever.
Check how the axle moves. If it is free, then it is necessary to change all the bushings, and do not forget to lubricate new parts with special grease before installing them.
To replace the spring, it must be pulled out, and for this you need to dismantle the retaining ring and the hinge with the lever. In the case when it is impossible to do without replacing the ball joint, carefully spread the spherical washer with your fingers and remove the worn part. At the same time, when installing a new one, lubricate it.
Traction same change as follows. At the bottom of the car there is a clamp, you should loosen its tightening. Next, you need to disconnect it from the hinges and, by unscrewing the fastening nut, you can freely pull out the rod. Installation of a new one is carried out in reverse order. Thus, replacing all damaged elements with new ones, you can drive safely. At the same time, do not forget that periodically it is necessary to adjust the gear lever.
