An improved design of an air spring with an air damper for self-regulation of the amplitude and frequency of oscillations of the Volzhanin and KavZ bus systems is presented. In the spring, the elongated piston is welded from two serial parts and made of fluoroplastic-4 for operation without lubrication. The check valves are closed with thin elastic tubes; the elastic rod is a wire with a diameter of 3 mm made of spring steel. The operating modes and dynamic elastic characteristics of the air spring are shown. Optimal design parameters were tested at the stand. It is possible to eliminate suspension hydraulic shock absorbers, which simplifies the design, reducing costs and increasing reliability.

1.1 Information about the MAZ-103 bus

Rice. 1. Bus MAZ-103

Brand:………………………………………………………………………………MAZ-103

Manufacturer:……………………… RUE "Minsk Automobile Plant"

Body type:…………………………………………………………………………………bus

Number of doors:………………………………………………………………………………...3

Overall dimensions, mm……………………………………..11985-2500-2838

Outer turning radius, mm……………………………………………11300

Number of seats……………………………………………...24

Maximum speed, km/h………………………………………………………………..…80

Engine………………………………………………………….Deutz BF6M1013EC (E2)

Working volume, l:……………………… ………………………………………………………..7.12

Engine power, kW (hp)………………………………………………………... 174 (237)

Gearbox………………………... Voith Diwa D851.3E (automatic)

Wheels……………………………………………….....disc, 8.25x22.5

2 General view and arrangement of suspension units of the MAZ-103 bus

When analyzing the suspension of the MAZ-103 bus, we select the main elements and present a detailed structure of the units in order to identify the main failures and malfunctions during operation of the MAZ-103 bus.

2.1 Front suspension

Rice. 2. Front suspension design of MAZ-103

1-Cylinder air suspension assembled; 2.3-Nut M30x1.5-6H; 4-Washer 12OT; 8-Bolt M12x1 25-6N; 9-Nut M8-6N; 10-Washer 8T; 12-Bolt M8-6gx50; 13-Cotter pin 1.6x20; 14.18-Coupling; 15-Washer 6; 16-worm clamp; 17-Axis; 19-Traction; 20-Shock absorber; 21-Hub with fist and brakes, right; 22-Front suspension base; 23-Amplifier; 24-Nut; 25-Nut M10-6N; 26-Screw M10-6N; 27-Cotter pin 5x36; 28-Nut M24x2-6N; 32-Transverse thrust; 33- Left hub with fist and brakes; 34-Bulb; 35-Transverse thrust; 37-Bolt M18x1.5-6N; 38-Bolt 3M14x1.5-6gx50; 39-Flange; 41-Bulb; 42-Key 6x9; 43-Finger; 44-Stand; 45-Piston; 46-Buffer; 47-Bulb; 48-Washer 14; 49-Washer 14L; 50-Bolt M14x1.5-6gx50; 51-Rubber-cordan shell; 52-Flange; 53-Bolt M18x1.5-6N; 54-Nut M18x1.5-5N6N.

2.2 Front suspension

Rice. 3. MAZ-103 front suspension design

1-Front axle; 2,3-Support; 4.5-Jet rod; 6-Shock absorber; 7-Air suspension cylinder assembly; 8-Body position regulator; 9-Rod of the regulator; 10-Axis; 11-Bulb; 12-Flange; 13-Lever; 14-Bolt 3M14x1.5x6gx50; 15-Cotter pin; 16-Nut M8-6N; 17-Bolt M8x6gx50; 18-Bolt M8x6gx25; 19-Washer 8T; 20.28-Buffer; 21-Washer; 22-Bolt 3M24x2-6g-60; 23-Cotter pin 1.6x400; 24-Splint 5x36; 25-Nut M30x1.5-6N; 26-Flange; 27-Piston; 29-Bulb; 30-Bolt m14x1.5-6; 31-Washer 14; 32-Washer 14; 33-Rubber cord casing; 35-Right tip; 37-Bolt; 38-Washer; 39-Nut.

2.3 Suspension bar

Rice. 4. Structure of the MAZ-103 suspension rod

1-Head; 2-Bolt M12x1.25-6gx60; 3-Bar; 4.5-Hinge; 6,7,16,18,19-Ring; 8-Rod head; 9-Hinge; 10-Washer 16OT; 11-Bolt M16x1.5-6gx60; 12-Ring 140; 13-Nut M12x1.25-6gx60; 14-Washer 12OT; 15-Pipe; 17-Hinge.

2.4 Rear suspension

Rice. 5. Rear suspension device of MAZ-103

1-Transverse thrust; 2-Beam; 3-Axis locking cylinder; 4-Hub; 5-Brake right; 6-Left brake; 7-Cover; 8-Gasket; 9-Washer; 10-Nut; 11-Bolt M12x1-6gx90; 12,13-Swivel knuckle; 14-Left tropecia lever; 15-Right tropezium lever; 16-Shock absorber; 17,18-Jet rod; 19-Pneumatic cylinder; 20-Flange; 21-Plate; 22,29,30-Nut M32x2-6N; 23-Bolt M24x2-6gx90; 24,25,26,27-Bolt; 28.31-Washer 4; 32,33,34-Washer 16OT; 35-Cotter pin 5x45; 36-Cotter pin 6.3x71.

The comfortable city bus MAZ 103 is used for passenger transportation. Its production began in 1996, but the official year of birth is considered to be 1992, it was then that MAZ signed an agreement with the German company Neoplan, specializing in the production of buses. The need to create local bus production in Belarus was due to the fact that the amount of transport regularly supplied from Hungary began to decrease noticeably, and the wear and tear of the existing fleet was already making itself felt.

Unfortunately, there was not a single enterprise in the country that would produce passenger buses, so MAZ, the largest engineering plant in Belarus, had only one option - to master production on its own. To do this, as part of the signed agreement, Neoplan transferred a license to the Minsk plant to produce the bus.

A year later, in 1993, six new buses were produced, which were practically no different from the base model. However, there was little good in this. Firstly, the cost of the assembled buses was shockingly high - $200,000. In the mid-nineties, not a single enterprise could afford to spend that kind of money on purchasing vehicles. In addition, used Ikarus from neighboring Germany were several times cheaper. Secondly, the bus had many defects, and its service life on Belarusian roads would be very short.

The question "what to do?" I didn’t stand in front of the factory for a long time. The decision to adapt the bus to local operating conditions suggested itself. No sooner said than done. The designers immediately began refining the design of the vehicle and began looking for options for replacing imported elements with more affordable locally produced parts. During the work, the bus was assigned the index MAZ-101. In 1996, the Belarusian plant introduced the first low-floor bus in the country - MAZ 103, which was immediately put into mass production. The price of the updated transport has become almost 2.5 times lower. It was possible to reduce the cost of production due to the fact that the share of imported spare parts for the MAZ 103 was reduced to 10 - 15%.

Comfortable and spacious passenger bus

There is no need to talk about the advantages of the lower sex. Disembarkation and pick-up of passengers is done more quickly and conveniently, and this, in turn, significantly reduces travel time along the route. It must be said that the MAZ designer was unable to fully reproduce the design of the German Neoplan. Due to the fact that the engine had impressive dimensions and was located in the rear of the cabin, the floor there was raised. Stepless entry remains at the front and middle doors, where the floor level reaches 360 mm. Near back door The floor height was increased to 580 mm, which required two steps.

In general, the MAZ 103 bus turned out to be comfortable, roomy and safe and quickly gained popularity not only in its homeland, but also abroad. In addition, the transport was distinguished by good maneuverability, which allowed it to feel more confident in dense city traffic.

The rear axle, which is the drive axle, has a bevel gear offset from the transverse axis and is made according to the classical design. The MAZ-103 is presented in several versions: in addition to the main model, the manufacturer also offers a modification for suburban passenger transportation - MAZ-103S. The differences are in the quantity increased to 45 seating and no back door. Basic model has several configurations, differing in passenger capacity and number of seats. The number of passengers carried is 90 - 100 people, and the number of seats is 21 - 28.

As for the internal structure of the MAZ 103 bus, the arrangement of passenger seats is made according to a three-row design: double on the left side, single on the right. Opposite the middle door there is a spacious storage area. The driver's cabin is quite spacious, with convenient layout of controls. Although the dashboard is a bit angular compared to Western bus models, the information on it is easy to read.

From the cheapest to the most expensive: engine options vary

The technical characteristics of the MAZ 103, along with modern design and a high degree of comfort, were another reason to be proud of the new bus. The very first models of passenger transport were equipped with YaMZ and MMZ engines, but already during operation it became clear that Yaroslavl engines were absolutely not suitable for it. They were not powerful enough, but they were noisy, large, heavy and poorly compatible with the gearbox proposed by the designers.

The engines of the Minsk Motor Plant, with a power of 320 hp, at that time turned out to be the best option and for the first few years of production, all low-floor units were equipped with them. Until 2004, MAZ 103 buses were also equipped with Renault engines. More reliable and powerful (250 hp), they inspired more confidence among drivers.

Currently, MAZ offers several engine options, including Mercedes-Benz (231 hp) and Deutz (237 hp). Units from well-known foreign manufacturers are highly reliable and comply with stricter environmental standards.

If we talk about the gearbox, the bus was initially equipped with a 6-speed transmission of its own production, but its incompatibility with a number of engines forced the designers to look for other options and most buses began to be equipped with a 5-speed Praga gearbox. Recently, MAZ has been offering buses with manual transmission manufactured by ZF or hydromechanical company Voith.

Long-term experience in operating this model has shown that the transport is quite reliable, can handle significant loads, and the possibility of breakdowns is minimized. If repairs are necessary, all spare parts for MAZ 103 buses can be purchased through official dealers plant, fortunately their network is widely developed in our country.

The price of MAZ 103 starts from 4,105 thousand rubles for a new bus.

Photo of MAZ 103 passenger bus

Minsk residents conceived the idea of ​​producing buses back in 1992-1993. Then a license was purchased from the German company Neoplan to produce a low-floor city bus of the 4014 series. However, the released model “did not work” due to the high price and expensive maintenance. To save the situation, it was decided to make cars using Belarusian and Russian components, while maintaining the “Neo-Plan” design and layout. So in 1995, our hero appeared on the assembly line, produced by AMAZ, a bus branch of the Minsk Automobile Plant.

In addition to Belarus and Ukraine, the MAZ-103 is also supplied to Russian cities: St. Petersburg, Yaroslavl (an assembly plant for MAZ buses was also recently established there), Novy Urengoy and so on. This year it was Moscow’s turn, which received 80 new cars. Using their example, we will analyze the design features and first operating experience. Since the bus is low-floor, there are no steps. The height of the footrest above the road is only 335 millimeters, so spacious salon you just enter, rather than climb like a mountain climber. Inside, it’s unusual at first: you drive low, and because of the huge glass area, you feel like a fish in an aquarium, on display for everyone to see.

But passengers seem to like the car. Drivers said that at first many people at stops did not even deliberately board passing buses, waiting for the MAZ-103 to pull up to the stop - they had to try out the new product! The driver is not deprived of attention either. The air-suspended seat has three levels of adjustment, and steering column adjustable in height and angle of inclination. Near the seat is an independent Webasto air heater. The dashboard displays indicators of sensors that monitor the condition of filters and main components of the bus.

In addition, if, for example, the system “detects” a low coolant level or a lack of oil in the power steering, the alarm signal on the panel is duplicated by a buzzer. The electrical wiring runs along the ceiling and is routed to a single switching unit located on the outer wall of the driver's cabin. The design features include a constant “mass”. Only the “plus” is switched off, but at the same time the necessary control units over the machine remain energized. Now about the problems. The first is assembly flaws. The panels in the cabin rattle and squeak, so drivers have to make “noise insulation” themselves, padding the parts with foam rubber. The second problem is electrical. The system itself is quite complex and difficult to understand.

Various relays (also, by the way, MAZ relays) fail: direction indicators, wipers, and so on. Due to moisture ingress, failures of the pneumoelectric brake light sensors and the air pressure indicator also occur. There were also problems with heating the passenger compartment: some buses had a batch of low-quality rubber pipes through which antifreeze leaked. Installing additional clamps eliminated the leak only temporarily. The problem went away after installing better products from another factory supplier. The manufacturer took this nuisance into account and now, for insurance, additionally seals the pipes with sealant. At the request of the customer, MAZ-103 is equipped with MMZ engines, MAN, Mercedes-Benz or Renault.

All buses operating in Moscow are equipped with one type of engine – an in-line Renault diesel engine of the MIDR 06.02.26Y41 series. 6-cylinder engine with turbocharging and intercooler with a displacement of 6.18 liters. develops power of 250 hp. and produces 950 Nm of torque, which is quite enough for a 12-meter colossus gross weight 18 tons. Some engines meet Euro-1 environmental standards, some are equipped with a mechanical injection pump electronically controlled comply with the Euro-2 standard. We open the hood and immediately notice the unusual arrangement of components. Due to the low floor of the cabin, the engine did not fit in the center of the compartment, so the engine and its components were moved to the left side.

As a result, there is a motor shaft in the cabin, which passengers initially mistook for... a toilet, fortunately the dimensions are suitable. On the other hand, although this box eats up part of the rear platform, through a large hatch you can get to the engine without leaving the cabin. The engine radiator is placed almost under the roof, which creates the effect of a water tower: antifreeze will flow into the system under any conditions. Expansion tank, in addition to the main section, it also has a reserve section, where, in case of excessive expansion, excess coolant and steam go, thereby protecting the system from rupture in case of overheating. The engine itself has a fairly high thermal regime - 80-90 o

Interestingly, the radiator fan has hydraulic drive, for which a second oil pump is installed on the engine. For the Germans, this system works without failures, but at MAZ, due to low-quality seals, pressure filters and control valve blocks that set the fan speed began to leak. (By the way, they say that similar valve blocks were previously used on hydraulic transmissions of deployment and control mechanisms for missile systems. And during the Soviet Union, designers would have worked on eliminating the above malfunction in Kolyma...).

Everything would be fine, but the oil gets to the second generator located at the very bottom of the engine compartment (the standard unit is not enough to meet the needs of the electrical system, so the plant additionally installs another generator of the same kind). Minsk residents took note of this and began installing one powerful generator on cars coming off the assembly line, which stands above the engine. Along the way, the designers simplified the fan hydraulic drive system, redesigning it according to German version, thereby eliminating the problem of leaks: instead of a control valve block, an oil pressure regulator was installed with control from a temperature sensor, and a pressure filter was installed in a sealed tank.

In order to reduce the cost of design and simplify maintenance, the engine is equipped with a MAZ exhaust system. So the sound of the engine is appropriate and clearly not “French”. Talking about the engine, it is also impossible not to mention that the car is equipped with automatic fire extinguishers: three of them are in engine compartment, one is above the engine liquid heater. Very useful things, considering that the engine is actually located in the cabin. In general, apart from the above-mentioned malfunctions of the mounted units, there are no comments on the engine itself yet. The engine is reliable, starts well in winter and is quite suitable for use in Russia.

However, repairmen would prefer to see on the car Mercedes-Benz engine, which has already been well studied on the 0325 series buses of the same name, which are produced in Turkey. And although the plant trains fleet mechanics to work with equipment, the French engine is still a new product for Moscow and there is still little experience in operating and repairing this engine in the capital. MAZ vehicles operating in Moscow are equipped with two types of manual transmissions. (The design also provides automatic transmission Voith transmissions). Sixty-six of the 80 cars have a 5-speed Czech gearbox Rgada 5RP4 (MAZ-103-041), the rest have a 6-speed Renault G406 gearbox (MAZ-103-040) with a Valeo clutch. There are no comments yet on the French unit. Several Czech gearboxes already have a problem: while driving, fourth gear spontaneously switches off.

You have to either ride third, or jump from third to fifth. Naturally, such a “ragged” driving style does not add life to the clutch. It is noteworthy that there are practically no such problems on buses operating in Minsk. It is still difficult to say whether the batch of checkpoints arrived in Moscow with a defect or there are some other reasons. Now engineers are working on this drawback and, hopefully, will eliminate it in the future. The bus suspension is pneumatic, with six cylinders. Note that the front suspension is independent, with two wishbones. This design made with the expectation of installing (on request) a system that, after “mooring” to a stop, releases the pressure in the air cylinders on the right or left side, tilting the bus on its side so that it almost lies on the ground, further facilitating access to the cabin.

The suspension has an active operating mode. Using three air valves, you can set several body height positions above the road. And when driving, the system not only maintains a given level, but also prevents the car from falling over in turns, increasing or decreasing the pressure in the airbags. There is a weak link here too. Pneumatic cranes are connected to the suspension arms and, sensing their movements, transfer air from one cylinder to another as needed. These cranes are located in a place that is not the most protected: the two front ones are in the wheel arches, the one rear one is near the bridge. Dirt flying from the wheels penetrates the faucet and its plastic piston begins to jam.

The pressure is not relieved properly and as a result the bus rides with a bias on one side. True, this defect was not widespread and mainly occurred on several buses of early production, where the cranes may not have been finalized yet. After replacing the faulty components with more advanced ones, the problems, as a rule, stopped. The brakes on all wheels are drum brakes, with self-adjusting clearances and ABS. But today this will not surprise anyone. But the fact that the entire pneumatic system is laid along the ceiling is something you don’t see every day and not on every bus! Although air system It has an air dryer and valves for draining condensate under the driver's window. There are similar drain taps on other buses, but on the MAZ they are easiest to use: tilt the panel, remove the caps, press on the washer - and water starts flowing.

When ordered, the bus is equipped with another interesting function aimed at increasing safety: when the driver presses the door open button, the automation simultaneously “locks” the bus parking brake. Steering with a distributor and a separate hydraulic booster, also taken from MAZ trucks. Among the malfunctions on about a dozen cars, squeezing out of the cuffs on the power pump and steering mechanism was noted. Mechanics attribute this to the fact that these machines stood idle for several months before being put into operation for various reasons. At the same time, the lubricant contained in the units exceeded its shelf life and, having thickened, began to squeeze out the seals during operation.

©. Photos taken from publicly available sources.

the new bus starts back in 1992. Then the MAZ plant, known in the world as a manufacturer wide range trucks, had no experience in developing passenger transport. The concluded agreement with the famous German manufacturer Neoplan on cooperation in production allowed the Minsk plant to obtain a production license and the necessary technologies, which significantly reduced the time and cost of development at the initial stage.

This step for the young republic was not in the area of ​​image, and not even in the economic area - its own bus became a vital necessity, since the Hungarian Icarus, which was widespread in the USSR in those years, with the collapse of the CMEA, began to curtail production and supplies to the CIS countries, including and due to the difficult economic situation in the republics of the former USSR, including with currency. Wear and tear quickly put the Ikarus bus fleet out of service. A replacement was required, and it was cost-effective and efficient.

As a result, the largest machine-building plant successfully mastered independent production and already in 1993 the first six Belarusian buses, which were a copy of the base model, rolled off the assembly line. However, the final cost of the assembled buses turned out to be significantly high - about 200 thousand dollars, which made the project unviable, especially since the former CMEA republics sought to sell off their old Ikarus "cheaply". Plus, the service life of the equipment in non-ideal road conditions turned out to be low. And as a result, adaptation to local conditions and local components began.

The result of the work was the launch of the low-floor MAZ 103 bus into serial production in 1996. Thanks to the reduction of imported components to a minimum (up to 10%), the price was more than half lower than competitors, the cost of ownership also decreased, maintainability and service life increased under the operating conditions of Belarus and CIS countries.

It should also be noted that the Maz 103 became the first low-floor bus produced in the CIS countries. It turned out to be roomy, safe and comfortable - meeting international standards, thanks to which it gained popularity outside the Republic of Belarus.

Technical features

Scheme bus chassis made according to the classical design, with a rear drive axle, with a bevel gearbox.

MAZ-103 today is already presented in several modifications - for suburban passenger transportation, with a different number of doors (without a rear door), with a different number of seats, and with different capacities.

Bus seating arrangement MAZ 103 is made according to a three-row design - double on the left and single on the right. Opposite the middle door is a storage area.

Driver's cabin with an ergonomic arrangement of controls, a comfortable seat and an adjustable steering column. Dashboard has no frills, but is made at a modern level and fully meets the goal of reliable and comfortable control.

Historically, the bus began to be equipped with engines from the Minsk Motor Plant with a power of 230 hp. They were too large, heavy, there was not enough power, and the noise was just higher than desired. For these reasons, in the early 2000s, Renault engines were installed on MAZ 103 buses - more reliable and powerful (250 hp), there were also modifications from DEUTZ and Mercedes.

Line power plants

Currently, only engines manufactured by Mercedes-Benz (286 hp or 326 hp) are installed. Aggregates famous manufacturer from Germany are distinguished by a high degree of reliability and efficiency and comply with more stringent environmental standards (Euro-5).

In terms of gearboxes, the bus was initially equipped with a 6-speed gearbox of its own production, but it was not compatible with a number of engines, which forced the designers to look for other options, as a result, most buses began to be equipped with a 5-speed Praga gearbox. Recently, configurations have been offered with a manual transmission manufactured by ZF or an automatic transmission from Voith or Allison.

Long-term operating experience of the model has shown its reliability and efficiency. Low comparative operating costs and cost of spare parts. In addition, spare parts can be ordered through a developed system of official dealers of the plant.

The price of MAZ 103 at the end of 2015 is from 6,500 thousand rubles for a new bus.

Basic elements of the series

• Independent liquid heater 30kW Webasto engine used for preheating engine and interior heating
• Independent air heater driver's cab 2.0-2.2 kW (Webasto or Eberspacher)
• Anti-lock braking system ABS
• Traction control system ASR
• Radio equipment without radio: microphone, amplifier and 4 loudspeakers
• Thermal and noise insulating ceiling coating
• Anti-corrosion treatment of the bottom and hidden cavities
• Folding ramp for wheelchair access
• Equipment and mounting for one wheelchair
• Forced body tilt system "Kniling"
• Driver's seat on air cushion, adjustable, manufactured by MAZ OJSC
• Wear-resistant coating "Grabiol"
• Galvanized sheet on sides and roof
• Stop Request Buttons
• Screw-in towing forks
• Partition separating from the salon workplace driver and dividing the doorway into two parts, without exit to the passenger compartment

Advantages and disadvantages

The advantages of the model include, in addition to the above, high visibility in the driver’s cabin and high maneuverability.

Thanks to the low floor, disembarkation and embarkation of passengers is quick and convenient, and stopping time is reduced.

The disadvantage of the bus is the large dimensions of the engine located in the rear of the cabin, which is why it was not possible to implement a stepless entrance, equally low for all three doors. As a result, the floor height for the rear door was 580 mm, versus 360 mm for the front and middle doors. A 220 mm high step was also created for the rear door.

The rear drive axle of the MAZ-103 (Figure 5.3) is made according to the classical design with a double spaced main gear and a bevel gear offset from the transverse axis of the bridge. It consists of a crankcase, a central bevel gear, planetary wheel gears and shoe brakes.

1 – control plug; 2 – wheel drive cover; 3 – cracker; 4 – emphasis; 5 – drive gear; 6 – carrier; 7 – lock-nut; 8 – hub bearings; 9, 15 – cuffs; 10 – oil catcher; 11 – brake shoe; 12 – spring; 13, 17 – spherical bearing; 14 – front knuckle support; 16 – expansion fist; 18 – rear knuckle support; 19 – oiler; 20 – adjustment lever; 21 – brake chamber bracket; 22 – axle housing; 23 – bevel gearbox; 24 – control valve; 25 – brake shield; 26 – caliper; 27 – pad axis; 28 – bronze bushing; 29 – ABS sensor; 30 – brake drum; 31 – bolt; 32 – axle; 33 – clamp; 34 – axle shaft; 35 – driven gear hub; 36 – screw, 37 – driven gear; 38 – bearing; 39 – satellite; 40 – satellite axis

Drawing5 . 3 – Drive axle MAZ-103

The wheel drive is a planetary gearbox consisting of spur gears with external and internal gearing. Drive gear 5 mounted on axle shaft splines 34. Four satellites 39 on bearings 38 installed in carrier sockets 6. The carrier is rigidly connected to the wheel hub 33. driven gear 37 through the hub 35 rigidly connected to the trunnion 32, the hub is held against axial movement by a nut 36. Axle shaft movement 34 limited to crackers 3 and emphasis 4.

Rear wheel hub 33 mounted on a trunnion 32 on tapered roller bearings 8. Bearing adjustment 8 carried out with a nut 36, which is locked with a lock nut 7 . Cuffs 9 prevent oil from getting from the axle housing to the shoe brakes. Trunnion 32 bolted to the axle housing 31. On the hub bolts 33 brake drum installed 30. Into the wheel drive cover 2 control plug screwed in 1 and an oil drain plug.

Shoe brakes are located between the caliper 26 And brake drum 30. Pads 11 mounted on axes 27 in the caliper 26 on bronze bushings 28 and press against the expansion fist profile 16 tension spring 12. Fist 16 installed in supports 14 And 18 on spherical bearings 13 And 17. At the end of a fist 16 adjusting lever installed 20 , inside which there is a mechanism for automatically maintaining the set gap between the pads 11 and brake drum 30.

Oil catcher 10 serves to collect and discharge outward through a channel in the hub 33 leaked through the cuffs 9 oils Oil can 19 designed for supplying lubricant to the spherical bearings of the expansion knuckle support, for lubrication of the front support bearing 14 expansion knuckle and pad axles 27 Oil nipples and control valves are installed on the brake shield.

Bevel gear 23 located in the axle housing 22 From the left side. It consists of a pair of bevel gears 3 And 17 with circular teeth and differential. The transmission angle is 90°. Drive gear 17 installed in a glass 20 on two tapered roller bearings 18 And 21, which are adjusted using shims 1. The moment to the gear is transmitted through the flange 23. Cuffs 22 designed for flange sealing. driven gear 3 attaches to differential cup 5 bolts 9. Pins 10 designed to limit deformation of differential bearing supports. Inside the differential cups 5 And 13 a bevel differential with two semi-axial gears is placed 14 and four satellites 7 , rotating on the spikes of the cross 6.

Conclusion: During the work, the designs of gear main gears, cross-axle differentials of cars and buses, as well as their axle axles were studied.