How the perforator is arranged and works

A perforator is a must-have tool in the arsenal of any home craftsman. Its interchangeable attachments make it versatile and indispensable. In this article, we will explore the various components of a perforator and provide tips on how to use it properly.

What the perforator consists of

There are controls on the body of the tool, as displayed in the accompanying photo:

To fully comprehend the internal structure of the perforator, it is necessary to disassemble it. Encased within the plastic casing are the following key components:

• Electric motor
• Safety clutch
• "Drunken" bearing
• Flying piston
• Chuck

The perforator works on the principle of converting the rotational motion of the electric motor into a percussive-rotational motion of the nozzles. The electric motor powers the other components of the perforator mechanism. The safety clutch is in place to protect the technicians during operation. The eccentric bearing drives the piston, generating an impact force, while the chuck securely holds the nozzles in place. Now, let’s take a closer look at each of these components.

Electric motor

A motor comprises of two main components, namely the stator and rotor.

The rotor rotates within a constant electromagnetic field generated by the stator windings. Multiple windings are located on the rotor, with their coil leads connected to the armature contacts. One of the windings is energized while power is supplied through the graphite brushes to the armature contacts. By switching the windings, a slip field is created, which in turn rotates the rotor.

Depending on the tool, the electric motor can be arranged horizontally or vertically. Horizontal arrangement is typically found in lightweight perforators, while models with medium and high power are equipped with a vertical motor.

In the latter scenario, a reducer is incorporated into the perforator’s design to alter the direction of rotation, increase torque, and enhance the impact force of the tool.

The start mechanism on the handle controls the operation of the electric component of the perforator when the key is pressed.

Safety clutch

In order to prevent the chuck from rotating in case the working bit gets stuck, perforators are equipped with a safety clutch. This is an essential component as it helps prevent accidents and injuries. Without the use of a safety clutch, the powerful tool could be forcefully ejected from the hands, and the independent rotation of the perforator could easily cause harm to the worker. There are two main types of clutch devices used in perforators: friction clutches and cam clutches.

1. During normal operation of the tool, the disks of the friction clutch are tightly pressed against each other, allowing the rotational force to be transferred to the rest of the mechanism. If the rotation becomes difficult, the disks will slip, preventing overload on the drive.
2. The cam coupling consists of two halves with beveled projections that fit into grooves on the coupling part. These halves are held together by a spring with a specific stiffness. If the striking force surpasses the pressure of the spring, the tabs slide out of the grooves, disengaging the coupling. As a result, a distinct rattling sound occurs, leading to the cam coupling being commonly called a ratchet.

Impact mechanism

The perforators are designed with two types of percussion mechanism:

• electromechanical;
• electropneumatic.

The electropneumatic variant is the most commonly used. The percussion mechanism of the perforator consists of an "intoxicated" (oscillating) bearing and piston.

When the main shaft turns, the rocker bearing moves back and forth, transferring force to the ram of the pneumatic cylinder. Inside the cylinder, the air pushes the piston along with the striker. The operative section of the chuck receives an impact from the striker, causing the drill held in the chuck to strike the material that is being worked on.

Chuck

The design of the perforator chuck allows users to easily replace the nozzle without interrupting their work for extended periods of time. There are two main types of chucks:

The SDS-plus chuck secures the tool shank with two locking balls.

SDS-max chucks fasten tools with alternative shafts to ensure a tighter connection.

What the tool can do

The perforator has several distinct modes of operation:

• Motion with rotation – enables drilling through concrete walls;
• Motion without rotation – for chiseling concrete;
• Rotation without motion – when equipped with a drill bit, it can be used as a regular drill.

Experienced hammer drill users are aware that this tool can also be used for creating hollow spaces in walls for wiring. It is relatively simple to create a conduit in concrete using this tool. Firstly, a series of holes are drilled along the marked lines. Then, the bridges between the holes are broken using a spade or trowel. Although this application of the perforator is unusual, it eliminates the need to purchase additional tools.

The perforator for making rough grooves enables you to achieve a result that is not as perfect as with a slot cutter, however, any imperfections can be concealed with plaster afterwards.

Safety of operation

To ensure your safety while using a perforator, it is important to adhere to certain precautions.

1. Before starting your work, always check the condition of the electrical cord. A damaged plug or insulation can potentially result in an electric shock. Additionally, inspect the housing for any cracks that may pose a safety hazard.
2. Ensure that all replaceable accessories are securely fastened in the chuck. Loose accessories can unexpectedly pop out during operation and cause injuries.
3. Avoid coming into contact with the rotating parts of the tool while drilling. The sharp edges can easily cause harm to your hands or other body parts.
4. Take caution when handling the attachments after completing your work, as they tend to become very hot. It is recommended to avoid touching them with bare hands to prevent burns.

Ensuring the correct utilization of power tools is vital for maintaining good health. It is imperative to adhere to safety protocols and utilize personal protective gear, including gloves, masks or goggles, and specialized work attire.