Gearboxes for walk-behind tractors - device, types and independent production. What role does the gearbox for the walk-behind tractor play in the operation of the unit? Homemade gearbox for walk-behind tractor

Modern walk-behind tractors consist of a minimum number of elements to make the equipment as easy to operate as possible. One of the most interesting topics among the owners of agricultural machines are gearboxes. Farmers are often debating what kind of oil to use to run a machine, or even how to make a device themselves.

Walk-behind tractor gearbox - device and functions

A gearbox, or, as it is also called, a converter is a mechanism that serves to process torque with its further transfer to the walk-behind tractor shafts. The mechanical transmissions of the machine are responsible for managing this process. In fact, the gearbox is that element of technology, the quality of parts and assembly of which determines the service life of walk-behind tractors. Therefore, the gearbox, coupled with the engine, is an integral part of the machine. When buying, the requirements for it are no less than for the walk-behind tractor as a whole.

Types of converters and their properties

After the increase in demand for gardening equipment, it became necessary to optimize various mechanisms for various purposes. This did not pass by and converters.

Types of mechanisms for the possibility of disassembly and reassembly

Depending on the ability to disassemble and repair the device, the converters are divided into:

Not collapsible converters - are installed on budget cars. Their production is cheap, since parts of low quality are used for production. The service life of such mechanisms is 1-2 seasons. Any malfunction in such a gearbox leads to its complete replacement.
Collapsible structures - mounted on expensive equipment. They are of high quality and are able to last for several seasons without a single breakdown. In the event of a malfunction, such gearboxes can be disassembled and the broken part replaced.

Types of gearboxes by purpose

Depending on the area where the device is used, the converters are divided into the following types:

As a rule, such a gearbox is equipped with a reverse function, which makes it possible to use the reverse gear of the equipment.

Self-manufacturing of a gearbox is just about complicated

Each of these types of converters has its drawbacks. Therefore, in order to repair the walk-behind tractor gearbox as little as possible, some farmers prefer to equip their equipment with home-made converters. Do-it-yourself construction often turns out to be of better quality and more reliable. For work you will need:

Phillips and flat screwdrivers;
Hacksaw for working with metal;
pliers;
Vise;
Welding machine.

First you need to weld the body. To do this, you can use stainless steel plates. To work, you will also need gears and shafts. They can be "borrowed" from the Friendship chainsaw. In this case, a hole will need to be drilled inside one of the tool shafts. On the opposite side of the gearbox, it is necessary to install a second shaft, and after it - bearings and a cage. The output shaft of the device is attached to the pulley. After that, the finished device should be placed in a previously welded case and pour engine oil inside.

The made converter is connected according to the same principle as the standard gearbox. Pay attention to the position of each gear. The elements should not be skewed, and their teeth should have perfectly even ends without kinks and other deformations.

At the end, you will need to test the converter. We advise you not to load it immediately after creation. To begin with, stretch the wound-up walk-behind tractor along the ground - let the elements of the converter connect and establish interaction. Only then can the equipment be used for its intended purpose.

A gearbox for a walk-behind tractor is equipment that converts and transfers torque generated from mechanical gears and makes the machine work.

It is the quality of the gearbox that determines the service life of the walk-behind tractor and the quality of its work.

What are the types of mechanisms

The motor block gearbox can be of several types.

Angle mechanisms

Equipment of this type is known for its high efficiency, and ensures that the transmission is mated to the engine. The angular gearbox for a walk-behind tractor, the price of which is at the optimal level, can be modified by the owner of the walk-behind tractor, which will significantly increase the power of the element.

The main components of the mechanism are:

generator housing;
flange;
flange fastening;
key and washer made of steel;
pulley mount;
a pulley having a V-belt type of transmission;
rotary shaft;
flange bearing, etc.

You can make such mechanisms yourself, with minimal knowledge and skills.

Gear and reduction gearboxes

The reduction gear is used to reduce the number of revolutions and increase power.

Such types of equipment are the most modern and reliable, as they are additionally equipped with a special cooling system that uses air in its work. Machines can withstand any type of load and perform many different functions. Even large-scale potato beds are not an obstacle to mechanisms.

Gear reducers have a fairly simple structure. Their transmission acts as a transmitter between the engine and the wheels. The advantages of the mechanism include reliability and ease of use.

Reverse gear

The reducer clutch is placed between the bevel type gears, which are freely placed on the main shaft. All this is called a reversal scheme, which is not very complex.

The main advantage of the equipment is the ability to reverse. Among the shortcomings of the mechanism, it is worth noting its low productivity and the impossibility of obtaining high speeds.

How to create a gearbox for a walk-behind tractor engine with your own hands?

The gearbox for the walk-behind tractor, the photo of which can be found on the site, is quite simple to make. This applies to the angular type of equipment, which has found wide application.

You can make a mechanism from ready-made samples that are taken from Dnepr or Ural motorcycles.

To work, you need to acquire the following equipment:

caliper and ruler;
straight and oblique screwdrivers;
saw blade for metal;
wire cutters and pliers;
vise and hammers;
rubber gaskets and other tools that may be needed in the process.

The device of the walk-behind tractor gearbox begins with the preparation of the body. In its capacity, as a rule, a 2-inch fitting square is used. The case can also be made by hand by welding metal plates. Very often, for this purpose, the factory shaft of the Ural generator is used and finalized properly.

The gears necessary for the gearbox can be taken from the Druzhba 4 chainsaw. At one gear shaft, you need to cut off the end switch and drill a hole of the required diameter in it.
The second gear shaft, complete with bearings and a cage, must be mounted in the housing of the future mechanism from the opposite side. On the output shaft, the master needs to fit a pulley that will provide rotation using a V-belt drive.

Fan bearings are attached to the hood ramp by welding.

What is the best gear oil to use?

The oil in the walk-behind tractor gearbox is the key to high-quality and reliable operation of the equipment. Choosing the appropriate option, you should first study the instructions. It is very important to consider the conditions in which the equipment will be used, as well as the loads that it will have to withstand. One of the most popular brands of oil is MOTUL, which is used by owners of walk-behind tractors almost throughout the country.

Reducer to walk-behind tractor price: what does it depend on?

The following factors affect the cost of the gearbox:

the number of functions performed by the walk-behind tractor;
quality and reliability of the device;
manufacturer;
power;
the possibility of reverse;
design features and much more.

As you can see, the gearbox of a walk-behind tractor is a rather complex design, without which the operation of the gearbox is simply impossible. Having a certain set of skills and abilities, you can make the equipment yourself. For those who do not have the right talent, the modern market offers a wide range of quality models at a variety of prices.

One of the most important elements of the walk-behind tractor is the drive. If you need to purchase a gearbox for a walk-behind tractor, then you should know that the service life of the entire unit will depend on its reliability. The gearbox for a walk-behind tractor, (made by oneself), is designed to convert and transmit the torque that it receives from mechanical gears and makes agricultural machinery work.

How to make a gearbox for a walk-behind tractor with your own hands

Between the worm and chain gearboxes for a walk-behind tractor there are differences in several important characteristics: gear ratio, efficiency, number of shafts and gears, angular speeds and power.

What are the gearboxes for a walk-behind tractor

Non-collapsible gearboxes are usually installed on cheap walk-behind tractors. The design of such a unit is not particularly reliable. It also has a short lifespan. In addition, it is impossible to carry out repairs or disassembly-assembly. In the manufacture of such units, low-quality metal and non-sleeved parts are used. In order to understand why it is impossible to use the gearbox for a long time, you need to familiarize yourself with its diagram.

It is customary to install collapsible gearboxes on expensive walk-behind tractors. Thanks to this, it is possible to disassemble the walk-behind tractor gearbox and carry out maintenance. They repair the gearbox of the walk-behind tractor to increase its service life, if high-quality spare parts are used when replacing faulty elements.

It is imperative to regularly diagnose the gearbox in order to repair the necessary unit in time. Regular lubrication of the gearbox should also be carried out, which will allow the unit to be used much longer.
Most often, a gearbox for a walk-behind tractor is used so that a high angular velocity is converted into a low one. The input shaft has a high speed and the output shaft has a low speed.

To avoid unexpected breakdowns, it is necessary to carry out regular maintenance, which will allow you to work successfully on an agricultural machine. If the change in angular velocity occurs in steps, the gearbox is called a gearbox, but if the change occurs steplessly, it is called a variator.

Homemade angular gearbox for walk-behind tractor

You can make a walk-behind tractor yourself. To do this, it will be necessary to calculate the rated power (Pn); Pn \u003d Pe (hp) x FS, as a result of which the correct type of angle is determined for the bevel gear. Torque and RPM are also calculated.

You also need to determine the operating conditions for a home-made gearbox for a walk-behind tractor, which includes: radial and axial load on the ends of the shafts, minimum and maximum temperatures, determination of environmental conditions, intermittent or non-intermittent operating cycle, type of lubricant.

After determining the technical parameters, you can begin to assemble the angular gearbox.
To do this, it is necessary for the angle gearbox to select a housing.

For example, you can use the factory one, from the Ural or Dnepr motorcycle. Then, based on the diameter of the gearbox housing, we make the gear shaft bearing housing from steel. Here we use the appropriate size drill and caliper. Then, in accordance with the intended dimensions, we select the gear shaft bearings (2 pcs).

We install a steel flange on the reverse side of the gearbox. It will have a steel washer and a flanged bearing inside. Using several screws, we fasten the steel flange to the generator housing. Before that, we select the driven gear shaft, steel key and drive gear. All nodes are connected to the transmission mechanism and the shaft of the rotary generator. The V-belt pulley is located on the transmission mechanism and is attached to the driven gear shaft with a nut and spring washer.
To assemble a homemade angle gearbox, you will need the following tools: a caliper and a ruler, a straight and Phillips screwdriver, metal drills, files and metal files, wire cutters and pliers, rubber gaskets, a vice and a hammer.

Angle gearbox for walk-behind tractor

The angular gearbox is widely used in motorcycle technology: in the automotive industry, modified cultivators, industry. When installing an angular reduction gear on walk-behind tractors, under heavy loads, they achieve more efficient operation.

This type of gearbox is usually used to connect the engine to a transmission designed for a chain. The angular gearbox for a walk-behind tractor is made from existing samples, similar ones are installed on Dnepr or Ural motorcycles. Then you will need to modify the gearbox.

The main elements of the angular gearbox

The components of the bevel gear are: generator housing, flange bearing, rotary shaft, steel washer, steel flange, bevel drive gear, bevel gear housing, steel key, pinion shaft bearings (2 pcs), driven gear shaft, bearing steel housing pinion shaft, pulley mount, V-belt pulley, flange mount.

Motoblocks with a gear reducer and a reduction gear for a motoblock

A reduction gear for a walk-behind tractor, in common people a creeper, is installed on modern diesel and gasoline air-cooled walk-behind tractors. Thanks to this, the user can use the walk-behind tractor on especially heavy soils for plowing and digging potatoes. The reduction gear helps with wheel slip when there is not enough own power.

Motoblocks with gear reducer

To understand what a gear reducer is, consider the structure of the transmission. It transmits torque from the engine to the wheels, and changes the speed and direction of the walk-behind tractor. The transmission consists of a gearbox, differential, gearbox and clutch. Transmission units are gear, chain, belt, or a combination of one or the other.
Gear transmission consists of bevel and cylindrical gears (gear reducer). It is used on some models of machines and heavy walk-behind tractors. The figure shows the gear transmission of the Ugra NMB-1 walk-behind tractor, which uses a gear reducer.

Reverse gear for walk-behind tractor

In the reverse gear, reversing is carried out according to the following scheme: between the opposite bevel gears, which sit freely on the drive shaft, there is a clutch.

She, being in extreme positions, clings to the splines on these gears. Therefore, when the clutch engages, the direction of rotation of the gear changes. The gears must be of the helical type. The clutch drive mechanism is a traditional fork or cam.

A lot has been said about the benefits of a walk-behind tractor in the subsidiary farm. If funds allow, they buy it. If you want to save money, make your own.

At first glance, this is a complex technical device that can only be made in the factory. In fact, a home-made walk-behind tractor with a gearbox from Ant is quite common in the yards of homegrown farmers.

If you understand the design, and have an elementary set of a locksmith in the house:

welding machine;
Bulgarian;
drilling tool.

then you can build a self-propelled iron horse literally from pasture materials. To do this, you need to understand how the design works.

Motoblock device. Basic structural elements

Frame or bed. An engine, a system for transmitting torque to the wheels, a suspension and a traction device for attachments are mounted on it;
Power unit. Its power can be small, from 5 to 10 horsepower. Engines from mopeds, motorcycles, compressors and even chainsaws are used;
Suspension. Usually primitive. Consists of homemade wheels or ready-made from agricultural machinery. Sometimes automobile or motorcycle ones are used. Can be axial or portal;
Gearbox for motoblock. One of the most important parts of the design. Designed to reduce the speed of the drive shaft with a simultaneous linear increase in torque. Quite often, a gearbox from a car or scooter is used as a gearbox.

However, the best option would be a homemade gearbox. It does not need to be paired with a power plant, since the calculation is made for specific tasks, and you are not limited to a ready-made technical solution.

How to make a gearbox for a walk-behind tractor with your own hands

First you need to decide on the parameters of the power plant. The technical specifications indicate the number of revolutions of the crankshaft. This is the first value that is needed for calculations. This figure is not constant, with the addition of "gas" the speed increases. Idle speed + 10% is taken as the base value.

For example, your engine idle speed + 10% is 600 rpm. The required wheel axle revolutions for a speed of 3 km/h are 200 rpm. Accordingly, your gearbox for a walk-behind tractor must have a gear ratio of 3: 1.

The idea of how to make a homemade gearbox for a walk-behind tractor was taken from the Modeler-Constructor magazine, the design of the unit was redesigned in accordance with the following requirements: exclude chain transmission from the transmission design, ensure the lowest possible center of gravity. Since the necessary gearbox was missing, the transmission was made from spare parts of gears for the engine of the Elektron scooter.

Motoblock: 1 - engine; 2 - casing; 3 - gas tank; 4 - ignition coil; 5 - switch; 6 - pin for fixing the angle of inclination of the working body (not shown conventionally in the top view); 7 - bolt M16; 8 - axis of attachment of the working body; 9 - working body (plow); 10 - holder; 11 - frame; 12 - carrier with control handles; 13 - wheel with lugs.

We make a homemade gearbox for a walk-behind tractor

To make a home-made gearbox for a walk-behind tractor, parts were taken from the V-150 M engine: crankcase, gears, chain sprockets, as well as an additional gearbox shaft. The crankcase must be cut into two halves and the kickstarter, gearshift mechanism and crank chamber removed from it. At the exit point of the kickstarter, it is required to install a plug and weld it using argon welding.

In the left half of the crankcase we install the bearing box of the right running wheel of the walk-behind tractor. A spare crankcase of the same engine is used as an axle box.

As the left cover, a part of the crankcase of the V-150 M engine is also used, which is supplemented with one part - a duralumin bushing. The sleeve is pressed into the crank chamber and has a hole corresponding to the diameter of the engine output shaft shank.

Chassis of a walk-behind tractor

1 - right wheel;
2 – left wheel;
3 – a gear wheel of the first transfer;
4 - drive shaft;
5- reducer;
6 - drive gear;
7 - bushing;
8 - locking screw;
9 - housing of the drive shaft;
10 - box flange;
11 - nut and bolt M8;
12 - slotted sleeve;
13 - shaft;
14 - nuts M14;
15 - washer;
16 - stuffing box;
17.18 - bearings;
19 - engine.

Walk-behind tractor drive shaft

1,2 - cantilever parts of the shaft (from the secondary shafts of V-150 M gears);
3 - gear wheel (from the gear of the first gear V-150M);
4 - front part of the shaft (bar d22 mm);
5 - cut off shoulder.

The motor and gearbox are fixed relative to each other by means of an M10 screw.

How to make a homemade walk-behind tractor with an ant gearbox

A two-stage chain gearbox is designed to reduce the rotation speed and increase the torque transmitted from the output shaft of the power unit of the walk-behind tractor to wheels or cutters.

Chain reducer drawing

1 - body made of channel No. 20); 2 - cover from Art. sheet s5); 3 - gasket made of oil and petrol resistant technical plate) 4 - drive sprocket of the second stage (z = 11, t = 19.05); 5-key; 6 - bearing 206 (2 pcs.); 7- compensation sleeve; 8 - shaft; 9 - nut M22x1.5 with a spring washer; 10 - stuffing box; 11 - remote bushing with keyway; 12-eccentric bearing housing (St3, 2 pcs.); 13 - M8 screw with spring washer (30 pcs.);

14 - driven sprocket of the second stage (z = 25, t = 19.05); 15- bearing 3008 (2 pcs.); 16 - bearing housing; 17 - sealing sleeve; 18 - left axle shaft; 19-oil drain plug (M10 screw); 20 - the bottom of the hull from Art. sheet s4); 21 - oil filler plug (Ml0 screw); 22.23 - oil seals (2 pcs.); 24 - right axle shaft; 25 - fixing screws M6 (8 pcs.); 26 - M8 bolt; 27 - chain t = 19.05; 28 - driven sprocket of the first stage (z = 57, t = 12.7); 29 - remote bushing

The first stage of the gearbox includes two sprockets with 17 and 57 teeth, respectively, with a pitch of 12.75 mm. The 17-tooth drive sprocket sits on the output shaft of the power unit, the driven sprocket sits on the outer flange of the second stage input shaft.

The second stage of the gearbox is reinforced and made with an 11-tooth drive sprocket and a 25-tooth driven sprocket, the tooth pitch is 19.05 mm. Since during the operation of the walk-behind tractor the second stage is located close to the cultivated soil, it is protected from dust by a closed crankcase, which is directly connected by welding to the crossbars, and the crankcase is connected to the spars by welding through steel spacers.

A strut is welded between the crankcase and the cross member for reliability. The crankcase is welded from two channels No. 2 with shelves, which are reduced in length to 35 mm. In the lower parts of the walls of the channels have the shape of a semicircle, instead of cut shelves, the bottom is welded from a steel sheet of 4 mm, which is curved along the walls of the channels in the form of a semi-cylinder. From above, the crankcase is closed with a cover with a gasket made of oil and petrol resistant technical plate.

Two coaxial holes d = 100 mm are made in both walls for bearing housings. Around each of them, six other threaded holes with M8 thread are evenly made, the purpose of which is to fasten the housings to the crankcase. The lower bearings of the semi-axes have conventional housings, the upper bearings of the shaft have eccentric housings. By turning them around the axis by at least 15 °, the chain tension of the second gear stage is adjusted in steps.

The shaft of the second stage of the gearbox is mounted in two ball bearings 206. By means of two spacer bushings, the drive sprocket is fixed exactly in the middle between the inner walls of the crankcase and is connected to the shaft by means of a parallel key. A large driven sprocket sits on the centering boss of the right axle shaft, fixed with six M8 bolts between the opposite flanges of the axle shafts. The lower part of the large driven sprocket and part of the chain are constantly immersed in oil.

The moving chain, when the motoblock engine is running, transfers oil to the upper part of the crankcase - thus lubricating the rubbing parts of the second stage is organized. To prevent oil leakage, stuffing box seals are provided in the bearing housings. A rigid flange connection of the axle shafts forms a single shaft mounted in two 308 ball bearings.