What The Screwdriver Consists Of
In each mechanism, the main function is performed by the motor. The screwdriver is no exception. It is the DC motor that is used in the hand screwdriver. It converts DC electrical energy into mechanical.
A screwdriver motor is a hollow cylindrical object, inside which there are magnets and a rotor mounted on special brass supports. It is a steel cylinder with longitudinal grooves around the circumference. A wire with a high magnetic permeability coefficient is laid in these grooves. The armature winding is a closed system of conductors. Through an equal number of turns, the rotor winding comes out to the collector, which is a cylindrical structure of copper segments isolated by a layered mineral.
Screwdriver motor brushes are made of carbon and graphite, which provides sliding contact with the rotating collector. The purpose of the brushes is to transfer electric current from the stator to the rotor. The voltage is supplied exclusively to the brushes, and the direction of rotation of the motor directly depends on its polarity.
To securely fix the brushes on the collector, a pressure device in the form of spring-loaded plates is used. Such a mechanism provides a clear correspondence of structural elements to their place, but at the same time leaves freedom of movement along the vertical. It maximizes the life of the motor as a whole.
This knowledge will be needed when performing maintenance and repair of the screwdriver. As a rule, the windings are the weak point in the motor, so you need to monitor the operation of the tool, especially when using it at extreme loads.
Power supply to the instrument
The supply of DC voltage to the electric motor of the screwdriver is carried out from a 220 volt network or using a rechargeable battery. It is produced in a small and compact design. This is necessary to reduce the weight of the hand tool and ensure ease of operation. The feeding device consists of several galvanic cells.
The rechargeable batteries are combined into one body and represent a single whole. The supply voltage, depending on the scope of the screwdriver, may be different. For household equipment, it is 9 volts, and for professional models it can reach 18 volts. The power of the power tool is directly proportional to the amount of applied voltage.
Using the information about the device mechanisms of the tool, a person will be able to repair the screwdriver himself, saving time and money.
Screwdriver, drill-screwdriver, screwdriver, electric screwdriver hand-held power tools or pneumatic tools with adjustable torque and / or screwing depth, designed for tightening and unscrewing screws, self-tapping screws, screws, dowels and other types of fasteners, as well as drilling holes (with a cam chuck or when using drills with a hex shank). An electric screwdriver operates from a battery or from an external power source (mains, generator), a pneumatic screwdriver from a compressor or a reservoir of compressed gas (usually air).
What the screwdriver consists of
The cordless screwdriver is not just a tool necessary for construction and repair, but also an irreplaceable assistant in everyday life. The device allows you to twist and tighten self-tapping screws, drill holes and perform other installation work in various hard-to-reach places. It does not require a cable and electrical network nearby, because it runs on battery power. With a cordless screwdriver, you can perform small household and other work efficiently and quickly.
The cordless screwdriver is a highly functional tool. It is used in everyday life and professional activities. These are construction, automotive, mechanical engineering, assembly production and other industries. It is used by residents of city apartments and owners of country houses when performing various construction and repair work. For example, finishing specialists use it to fix drywall and other finishing materials, furniture assemblers assemble cabinets, sofas and much more.
- Tightening screws, bolts, self-tapping screws, screws and other fasteners.
- Tightening dowels and anchors during installation work.
- Removal of screws, bolts, self-tapping screws, screws, dowels, anchors and other fasteners.
- Drilling metal.
- Drilling wood.
- Threading in Structures.
The cordless screwdriver is perfect for working in hard-to-reach places, as well as where there is no power supply. The screwdriver can significantly reduce labor costs and time. Depending on the needs and goals set, a screwdriver is selected. For example, most household models screw screws up to 5 mm. With a good screwdriver, you can work with self-tapping screws up to 10-12 mm. This also applies to the drilling operation: the maximum diameter of the drills used must be taken into account.
Rotation adjustment clutch
In order to prevent the thread from breaking off a part of the screw and breaking the tool itself due to overload, a rotation adjustment clutch is provided in the design of the screwdriver. It consists of a stopper, washer, threaded sleeve and spring. The device is connected to the parts of the cartridge. When a force in excess of the nominal occurs, the load is transmitted through the spring to the cylindrical rods of the cartridge, and they act on the sleeve. As a result, the ratchet is triggered and the chuck stops.
Screwdriver with screw-in depth adjustment
Commonly referred to as a drywall screwdriver. Has a screwing depth adjuster. Single speed hand tool. May have a torque regulator clutch (extremely rare). Not equipped with a jaw chuck. Drills with a hex shank must be used for drilling. May have a self-tapping device. Can be electrically powered or battery operated.
Varieties of chucks for a screwdriver.
When working with the tool, attachments for screws or drills are used. The standard shank of the bits is made in the form of a hexagon. A cartridge is intended for attaching the attachments and transmitting rotational motion to them. It is installed on the threaded end of the spindle and is secured against loosening with a screw.
The most common three-jaw, self-centering, self-locking chuck. Inside it, a hexagonal recess is made for installing the nozzle shank. It is fastened between the cams by rotating the clutch. The design of the coupling includes a retainer that allows you to clamp the nozzle without turning the spindle.
Battery and its characteristics
A battery is simply indispensable. It serves to supply a DC supply voltage to the motor. The battery is also installed in a small size. This allows you to significantly reduce its weight for ease of use. It is such a device at once several connected power supply elements, which are connected in series.
At the same time, they are all united in a single corpus, so they appear to a person as a single whole. The range of supply voltages for a screwdriver can be very diverse. It starts at 9 volts for home appliances, and can go as high as 18 volts for high-powered professional devices. Here you can put forward a direct pattern. The higher the supply voltage, the more powerful the screwdriver itself will be.
So, now everyone knows about what constituent parts a screwdriver consists of. As you can see, they are all quite simple. Knowing the device of the screwdriver, you can always draw conclusions about how it can be repaired. A person who has a strong theoretical base can always apply it in practice. Do-it-yourself screwdriver repair will always save a lot of money.
The screwdriver is an essential and indispensable tool in the home. With it, you can easily fix the drywall sheet during finishing work, unscrew or unscrew the screw, and also drill a small hole. And assembling cabinet furniture without a screwdriver is completely inconvenient.
The screwdriver is used both for industrial purposes and at home. Therefore, the choice of a screwdriver must be carried out depending on the purpose.
Choosing a screwdriver for home
If you are planning minor household repairs, then you can easily choose a screwdriver for your home. You can easily get by with a conventional model, where all the necessary functionality is already available, and such a screwdriver weighs much less than a professional model. With prolonged work, your hand will not get tired of excess weight.
If your repair promises to drag on, where you will have to screw or mount something on a daily basis, then your choice should lean towards a professional expensive model.
What the screwdriver consists of
Every man should have in his arsenal such a device as a screwdriver. It allows you to perform a wide variety of repair and construction work. However, with all the popularity of the screwdriver, not everyone knows about its device. In fact, there are not many elements installed here. The device of the screwdriver is as follows: planetary gear, DC motor, load limiter, battery, speed control button. This is where the list of devices ends. In fact, there may be more of them, but the standard equipment always includes only these five types.
Diagram of a cordless screwdriver device.
The tool is turned on by pressing the screwdriver button located on its handle. This push-button switch is combined with a voltage regulator, with different pressing forces, a different voltage is supplied to the electric motor, which is provided by a wide-pulse regulator. In the area where the button is installed there is also a lever for the direction of rotation. This switch allows you to change the polarity of the supplied signal, which provides a reverse rotation. The electric motor is started through a sufficiently powerful transistor, the opening process of which is controlled by a PWM generator.
The electrical signal is supplied directly to the motor rotor through a manifold. Graphite brushes of a certain size are used to ensure electrical contact.
It is this node that is the main one for a screwdriver. Execution is mostly standard. A DC motor is a cylinder with magnets in a circle. The anchor of this motor is held on special supports, which are most often made of brass. The motor windings, which are made of a material with a high magnetic permeability, are placed in the slots of this armature. The material of the armature body itself is steel. Through an equal number of turns, the winding has an outlet to the collector plates. Engine brushes, which are mostly made of graphite and metal, touch the surface of the armature in its tail.
Types of chucks for a screwdriver.
In order for the fixation to be reliable, the brushes must be pressed. They have a special mechanism. For clamping, spring-loaded plates are used. They allow structural elements not to leave their rightful place, but at the same time they can move along their vertical axis. This significantly reduces wear on the mechanism. If you look at the circuit of the constant motor, you can find that the voltage is supplied exclusively to the brushes themselves. In this case, the direction of rotation of the motor directly depends on the polarity of the applied voltage.
Naturally, this is a primitive device, but this knowledge is quite enough to carry out regular motor repairs. Most often, the windings fail in it. They can simply burn out from overloads, so you need to always make sure that the equipment does not work to its limit.
The mechanical part of the tool, designed for attaching attachments and transmitting rotary motion to them. Usually mounted on the threaded part of the spindle. Can be fixed with a screw, clamp or ratchet. Quality models have a retainer that allows you to clamp the drill or bit without additional scrolling.
Almost all modern screwdrivers in the professional and amateur segment are equipped with a three-jaw self-clamping chuck with self-centering. This allows you to quickly change attachments, securely attach them for long and intense work. There is a hexagonal hole inside the chuck for fixing the bit shank. Usually fastening occurs between all three cams by slightly rotating the coupling.
To install the nozzle, you need to grab the lower clutch, start turning the upper one, this allows the cams to unclench. To speed up the process, you can fix the nozzle by holding the upper sleeve and pressing the start button for clamping, reverse for unclamping.
Detailed screwdriver device: diagrams and
The screwdriver is a versatile tool that can be used for a wide range of tasks. Allows you to drill holes of different diameters, screw in fastening tools, and install and dismantle building elements. Outwardly, this is a small device weighing from 0.5 to 2 kg. It consists of a housing, an electric motor and a gearbox. It can also have additional functions, for example, an adjustment of the rotation speed, a locking mechanism and even a flashlight. To choose a quality model, you should take into account the purpose of the work, as well as the main technical characteristics.
- Electric motor
- Planetary reductor
- Rotation adjustment clutch
- Spindle speed adjustment
- Power supply and its characteristics
The small-sized motor of the collector type is the main part of the tool. The mains-powered screwdrivers are equipped with a two-phase AC electric motor, starting through a starting capacitor. Rechargeable models operate on a permanent power source. The main elements of the electric motor:
- A cylinder made of solid steel, inside it contains magnetic elements;
- The anchor part is fixed on brass supports;
- Windings from a material susceptible to a magnetic field are laid in the grooves;
- Through an equal number of turns of the winding there is an exit to the collector plates;
- Brushes made of graphite or other durable metal are attached to the tail of the armature.
For secure fixation, the brushes are pressed with a spring-loaded plate. This allows the integrity of the structure to be maintained as well as movement along the vertical axis. It is the brushes that wear out most often and need regular replacement.
Outside of the device with a contact handle.
The screwdriver body can have several types:
- Pistol. Used only in budget models of the screwdriver. The rotating shaft is directly attached to the chuck. Convenient for household purposes, copes with screwing. The main disadvantage is the high heating rate, as well as the need for pressure during operation due to low power.
- T-shaped. Outwardly, it resembles a pistol-shaped screwdriver, but the handle is shifted to the center. This ergonomics allows for comfort during extended work. It can be equipped with an electric motor of different power. Found application in compact models.
- Classic drill. common in professional models. It has a characteristic bulge in which there is a mechanism for transmitting force to the chuck through the gearbox. The movement of the bit is smooth, often with the ability to adjust the speed. An additional handle is desirable, since the weight of the tool can exceed 2 kg.
When choosing a screwdriver body, you should pay attention to the quality of materials of manufacture. It is advisable to choose models made of dense plastic with metal inserts and rubberized elements in the contact parts. The handle should lie comfortably in the hand, not cause discomfort. It is recommended that the power button, reverse button, and speed and power controls are easily accessible to your fingers. You shouldn’t buy a model with obvious backlash of any moving parts.
Regardless of the equipment of the model, it is always in a separate case, made of plastic or metal. The main elements of the screwdriver gearbox:
- Sun gear;
- Ring gear;
- 1-2 carriers.
The main part is an annular gear that has a cylindrical shape. Small teeth are located along its circumference, along which the satellites move. They are usually mounted on strong carrier pins with a sun gear in the center of the first row.
The movable shaft is inserted into the gearbox with the help of magnetic contacts, during operation it makes rotational movements. A two-stage gearbox always contains a second carrier. Given the complexity of the job, it can move faster or slower than the tool motor shaft torque.
Rotation adjustment clutch
It ensures that the movement stops at the end of work, for example, at the moment of complete screwing.
Such a mechanism eliminates the breakdown of the screw thread, overheating of the engine from overload. Consists of a stopper, washer and spring, threaded (adjusting) sleeve.
The adjustment clutch is integrated into a single mechanism with the chuck. At maximum tension, the spring transfers the load to the pins of the threaded sleeve, which stops the cartridge case. Then the rotational force stops. Depending on the design features of the screwdriver, the coupling is represented by 5-25 steps of adjustment.