When manufacturing carpentry construction products in factory conditions and performing carpentry and carpentry work in construction site conditions, manual electric tools and machines are widely used: electric circular saws, electric planers, electric drills, hand-held milling machines for chain boring, electric screwdrivers, electric wrenches, mobile planing machines and parquet sanding.
According to the principle of operation of cutting tools, manual electric machines do not differ from corresponding stationary machines. The advantage of electrified machines is their portability, ease and ability to perform various operations (cutting, planing, drilling, deepening and grinding) in any conditions. Therefore, they are widely used in assembly workshops when assembling and fitting doors and windows in their boxes, when installing windows and doors in buildings, when making arches, lattices, hangers and formwork in construction conditions, for planing and sanding parquet floors. the processing of products with electric machines does not completely exclude manual carpentry tools, since after cutting and planing wood with rotary blades, waves, scratches and other irregularities remain, which can be removed with a manual scraper or sandpaper.
The productivity of manual electric machines is several times higher than the productivity of manual carpentry tools. For example, the productivity of a circular saw is 4 to 10 times higher than the productivity of a hand saw
Circular electric saws are used for longitudinal and transverse cutting of planks, beams and other elements, for cutting plugs and other types of connections. The circular saw blade can have a right and left position, which makes this saw universal. In fig. 1 showed the circular saw I-78.
Figure 1: Universal electric saw type I-78
The electric band saw, which is used for cutting straight and curved elements of smaller dimensions, for cutting tongues and grooves, has not found much use at all.
Electric planers are used for planing boards, floors and other sawn timber. The productivity of an electric planer is 5 - 10 times higher than the productivity of manual planing. The working part of the electric planer is a rotary head with knives, which gets a rotary start from the electric motor. Electric planers brand I-24 and I-25 use an electric motor with an external rotor, which is also a rotating head with knives, on which four knives are fixed. The planer brand I-24 has a planing width of 100 mm, and the planer brand I-25 - 60 mm.
Electric planer I-24 (fig. 2) consists of a solid - strong frame; a motor is fixed in it, on the rotor of which an aluminum drum is threaded, on which there are four knives. The thickness of the removable cover is regulated by lowering the front table, using the adjustment screw. The rotating head with knives is closed with a protective cover.
Picture 2: Electric planer
This planer can be used as a table planer for planing and therefore there are 4 legs on the protective cover, so that it can be fixed on the base. The existing guide is used for planing the elements at an angle. The electric planer has a manual brake.
Electric drill type 1-27 with drive from an asynchronous three-phase electric motor is used for. drilling holes with a diameter of up to 26 mm and a depth of up to 1000 mm. For drilling holes with a diameter of up to 52 mm, a strong electric drill type SA-27 is used with an adjustment device that can be used to drill at an angle of 45o.
Hand boring machine is used for making rectangular grooves and tongues in construction site conditions. The cutting tool of this machine is an endless milling chain, which consists of individual joints connected by rivets. The productivity of a manual electric boring machine is up to 10 times higher than the productivity of manual work without a machine. Also worthy of attention is the type I-1 electric dredging machine.
Electric wrenches and electric screwdrivers are used for screwing and unscrewing screws, bolts, nuts, etc. In fig. 3 shows an electric key type TKO.
Figure 3: Electric screwdriver type TKO
The parquet planing machine 0 - 1 (fig. 4) is used for planing the surfaces of parquet floors.
Picture 4: Parquet planing machine 0 - 1
The rotor of a short-circuited electric motor, in the form of a drum, on which three planing knives are fixed, serves as the rotating head with knives of the parquet planing machine. Due to the high torque, the machine can remove wood chips up to 3 mm thick, which gives it an advantage over other parquet planing machines with a personal electric motor and a special rotating head with knives, which can remove wood chips up to 1,5 mm thick. With a cutting angle of 90o this machine can be used for fine planing. This machine moves using two front and two rear rollers.
For sanding parquet floors, a parquet sanding machine 0 - 8 is used (fig. 5).
Picture 5: Parquet sanding machine 0 - 8
Before putting the machine into operation, the safety of fixing the rotating parts, the direction of rotation of the sanding cylinder, the attachment of the sanding cloth, and the grounding of the machine must be checked. The machine should be put into operation with the sanding cylinder raised.
Grinding should be done in parallel strokes with overlapping of adjacent strokes by 30 to 35 mm, so that no marks remain on the overlaps. The machine can be turned while moving with the cylinder lowered. During the first pass, an additional load is placed on the machine, so that the ironing cylinder fits snugly against the surface to be sanded.
At the end of the work, the cylinder should be lifted; turn off the electric motor; disconnect it from the power supply and collect the electric conductor in the compartment designated for this purpose, carefully clean the machine from dust and carry out a preventive inspection of the machine.
When using hand-held electrified machines, labor protection regulations and sanitary regulations for manufacturing companies should be strictly followed.