|” February 2014 “|
–> –> –>Main » 2014 » February » 16 » How to choose an electric motor for a wood splitter.
|– voltage: 380 V; power: 5.5 kW; current nom.: 12.9 A; revolutions: 1000 rpm; weight: 71 kg; price 6100 rub.
– voltage: 380 V; power: 5.5 kW; current nom.: 11.7 A; revolutions: 1500 rpm; weight: 67 kg; price 5800 rub.
– voltage: 380 V; power: 5.5 kW; current nom.: 11.0 A; revolutions: 3000 rpm; weight: 36.5 kg; price 5500 rub.
– voltage: 220 V; power: 2.2 or 3 kW; current nom.: 11.0 A; revolutions: 3000 rpm; weight: 30.5 kg; price 3100 rub. – ONLY FOR CIRCULAR SAW 3000 RPM.
– voltage: 220 V; power: 2.2 or 3 kW; current nom.: 11.0 A; revolutions: 1500 rpm; weight: 36.5 kg; price 3250 rub. (low power for a circular)
– voltage: 220 V; power: 2.2 or 3 kW; current nom.: 11.0 A; revolutions: 1000 rpm; weight: 50.5 kg; price 3400 rub. – weak for a circular saw, BUT ONLY FOR A WOOD CUTTER 750-1000 RPM./MIN.
For power 2.2 kW / 3000 rpm. one profile B belt is enough . There is no single-phase 220 V motor more powerful than 3 kW. But the correspondence of 2.2 kW will be with a capacitor with a capacity of 50 microfarads (microfarads).
The calculation is usually as follows: 7 μF per 100 W of motor power – this is in the case of starting a 3-phase motor from a single-phase network. That. 2200: 100 x 7 = 154 microfarads.
The 220 V electric motor has two windings: main and auxiliary. In this case, the phase shift in the second winding occurs due to the capacitor and this capacitor is constantly included in the circuit. Therefore, 50 uF is quite enough and with such a capacitance (better than 30) and an average load, the rotating magnetic field is as close as possible to a circular shape. It is possible to increase the capacitance, but in this case, not a circular, but an arcuate, ellipsoidal magnetic field will appear and one of the windings will overheat. It is possible at the time of start-up to turn on for a short time additional. capacity, but then manually it will be necessary to turn it off after promotion.
For the splitter and circular saw, ONLY a 220 V, 3000 rpm (for circular saw), 750 rpm (for wood splitter), 2.2 kW motor can be used. Not bad for a circular, even for a fairly powerful one. If you put a disk about 300 mm , then the pulleys are optimally 1: 1, if the disk is 250 mm, then approximately 4: 3. Those. to get about 3 thousand rpm on the disk in the first case and 4-4.5 thousand in the second. The AIRE brand motor is single-phase, it must have a box with a phase-shifting capacitor. Therefore, the engine can be directly plugged into 220 V, no special starting measures are required. There must be 4 wires in the terminal box, the connection is usually indicated on the nameplate, often on the back of the terminal box cover.
Circular motor: 3 kW/3000 rpm: – Shaft diameter – 24 mm, height with key 24+3=27 mm, key width 8 mm. Shaft length 50 mm. Shaft to table 90 mm. Weight – 39 kg.
Wood splitter motor: 3 kW/710 rpm: – Shaft diameter – 32 mm, height with key 32+3=35 mm, key width 10 mm. Shaft length 80 mm. Shaft to table 112 mm. Weight – 48 kg.
Three-phase asynchronous squirrel-cage motors for general industrial use are designed to complete electric drives for domestic and industrial use, various mechanisms (machine tools, pumps, gearboxes, fans, hoisting and transport and construction machines, etc.). Differences: – for voltage 380 V (three terminals in the terminal box) and for 220/380 V (six terminals).
Efficiency at 380 V for motors 5.5 kW, 3 kW, 2.2 kW, respectively – 83%; 79%; 76.5%. Loss coefficient, respectively – 0.84 \u003d 4.62 kW; 0.74= actual 2.2 kW; 0.71=1.56 kW.
Current at 380 V for motors 5.5 kW, 3 kW, 2.2 kW, respectively – 13.6A; 7.8A; 6.2A
How to choose the right electric motor?
There are two engines for sale on the counter. Both – 2.2 kW, 3000 rpm, 220V, on legs, size 80 (shaft diameter 22 mm), the price is approximately the same (10% difference in price), produced by different factories. Which one is better to choose?
We recommend paying attention to such an engine parameter as its mode of operation. Look at the engine tags: one engine has a MODE (of operation): S1, the other: S6-40%.
What does it mean?
The operating modes of the electric machine are defined in GOST 183-74.
S6 – intermittent operation mode. A sequence of identical cycles of engine operation, in which each cycle consists of a period of operation with a constant load and an idle period. Moreover, the duration of the load periods should be such that the engine temperature does not reach a steady-state value.
The duration of the load (DL) is indicated in the engine parameters: 25, 20, 40 and 60%. The duration of one cycle is assumed to be 10 minutes (unless otherwise specified separately). The relative duration of the load is determined by the formula PN \u003d N / (N + V) 100, where V is the idle time. Thus: S6-40% means that the engine should run no more than 4 minutes under load, then 6 minutes of idling.
Can an engine labeled S6 be run in S1?
It is possible, but at a lower capacity. For our case, the AIRE 80C2 engine in S6-40% mode will develop a power of 2.2 kW (which is indicated on the tag). But in S1 mode (that is, with constant operation), such an engine will produce up to 1.8 kW (according to the manufacturer’s data). Increasing the load in this mode can lead to overheating of the engine and its failure.
http://instrumentimsk.ru/dvigateli_dlya_sadovoi_tehniki.html – here for the wood splitter you can choose gasoline engines from 5 kW – http://instrumentimsk.ru/Dvigatel_Robin_Subaru_EX21_Premium.html (in the absence of 3-phase electricity or as such completely – in the forest or on the development of firewood) or power plants for engines: http://energo-diesel.ru/generator.html
We use wedge belts with a type A profile (13 (w) x8 (h) mm), for example A-46, 47, 48 with a length of 1168, 1194, 1220 mm, respectively (price from 40 to 180 rubles). There is also type B (17×11 mm), type C (22×14 mm), type D (32×19 mm), type D (40×25 mm) and the smallest type O (10×6 mm).
Geometric dimensions of V-belts ( A – Belt wedge angle, 40° ):
Calculation of engine power for a homemade screw wood splitter
To assemble a wood splitter with your own hands
Requires an engine or walk-behind tractor with at least 3.hp or 2.2 kW.
It’s simple, the higher the engine power, the higher the performance. With good power, you can stab immediately in the middle, and stab tangentially, disassembling in parts.
Video of the operation of a screw (conical) carrot splitter for walk-behind tractors with a 6.5 hp or 4.7 kW engine. For your wood splitter
by hand, you need an engine-motoblock + a mini set of pulleys or sprockets. Or you can immediately buy a kit for assembling a homemade wood splitter.
Horsepower: history and modernity
The idea of measuring engine power “in horses” capable of doing the same work was voiced in 1702 by the English inventor Thomas Avery in the book “A Miner’s Friend”. The term “horsepower” itself was introduced by the Scottish engineer and inventor James Watt.
In Russia, horsepower means the so-called. metric horsepower equal to 735.49875 watts. In Europe, horsepower is 75 kgf m / s – this is the power expended in uniform vertical lifting of a load of 75 kg at a speed of 1 meter per second with standard acceleration of gravity (9.80665 m / s²); in watts this would also be 735.49875. In the UK and US, mechanical horsepower is more commonly used, equal to 745.69988145 watts (that’s 1.01386967887 of metric).
The power of car engines is measured in different units and in different ways. Horsepower is gradually falling into disuse, but in Russia they are needed to calculate the transport tax. Some countries have by now refused to take into account power when calculating taxes and have paid attention to the dimensions of the car; other countries are guided in the same question by kilowatts.
Winter is approaching and for many residents of private houses this means the opening of the firewood season, if there was no time to do it in the spring. Bringing firewood under the yard is not the most difficult thing; splitting them can be considered the most tedious and lengthy. For those who do not like to chop wood with an ax or those who chop them en masse for the purpose of selling, you can make such a machine for yourself.
This is one of the simplest wood splitting machines. It works on the basis of an electric motor that drives a threaded cone, which is popularly called a “carrot”. As the cone climbs into the wood, it expands more and more and eventually the stump splits.
Materials and tools for homemade:
Wood splitter manufacturing process
Step one. We make the frame
If you are thinking of moving your machine, then equip it with wheels. The author adapted wheels with a size of 18 cm, as a result, the height of the machine was 80 cm. Of course, here the height must be selected according to height, the main thing is safety and convenience. We cut pipes and weld the frame.
Step two. Engine, pulleys and cone …
As for the cone, the author bought it, because he could not do it himself. This spare part will not cost too much if you order it from a turner. The thickness of the thinnest part of the cone is 8 mm, and the widest 80 mm.
Step three. Work table