It is difficult to imagine a modern set of repair and construction equipment without such an important tool as a rotary hammer. The principle of its operation is based on the functions of a conventional electric drill, which are expanded by reciprocating capabilities. They are responsible for a special mechanism that converts the rotational motion of the shaft into shock. If you need to repair the punch, it is most often this unit that fails, because it is subjected to increased loads.
Punch Design Features
The shock function in the electric hammer provides a special pneumomechanical unit. However, there are models of punchers in which a mechanical or electrical system is responsible for the impact. It should be noted that these tools are inferior in accuracy and performance to electric rotary hammers with a pneumatic impact formation system.
The design of perforators has its own characteristics, one of which is the use of especially durable drills instead of conventional drills. Due to its special shape, the drill is able to withstand more significant longitudinal loads than a drill drill with a percussion mechanism. The drill does not have a sharp cutting edge on the working end - it is replaced by a carbide tip. Meanwhile, the drill design provides for spiral longitudinal grooves, similar to the grooves of conventional drills. However, they are intended for the removal of crushed waste material during hole drilling. For this, the drill punch performs, in addition to the reciprocating, also rotational movements around its own longitudinal axis, which also contribute to the straightness and alignment of the drill in the material.
The chuck and shank of the drill are designed in such a way that it is not fixed rigidly, but has some freedom of longitudinal movement. This is done in order to prevent the loss of kinetic energy of the impact to disperse the cartridge, increase productivity and reduce the level of vibration of the hammer.
Strong pollination is one of the main causes of tool breakage, and the cartridge, in addition to a heavy load, also takes up the bulk of the dust. In order to repair the perforator cartridge does not turn into a chronic problem, it must be periodically cleaned of dust and dirt. Washings with gasoline or cleaning with compressed air are recommended . After cleaning, all elements of the cartridge should be re-lubricated.
Punch Reducer
The gearbox transmits torque from the engine to the hammer mechanism of the punch. It is a set of cylindrical, bevel and worm gears. The speed of rotation of the cartridge and the number of strokes are changed using electronic controllers. There are also models equipped with a two-speed gearbox.
The gearbox must be lubricated periodically, and grease is recommended for this. They are refueled when assembling, servicing or repairing the perforator gearbox.
The main causes of breakdowns
As already mentioned, one of the main causes of breakdowns of most sites of the hammer drill is heavy dusting. For example, the cooling of a collector engine is done by a fan, which together with air delivers dust particles to the engine. As a result of the friction of these particles on the armature and stator, these mechanisms wear out quickly.
If the tool does not turn on, one of the reasons may be damage to the winding, then punch repair is inevitable - you will have to tackle the stator and the armature.
Frequent breakdowns are also associated with the mechanical components of rotary hammers. Most models are equipped with mechanisms for switching operating modes (rotation, battle, rotation with battle). If at least one of these functions has stopped working, the switch is most likely to blame. To eliminate the breakdown, disassembling the tool will be required.
Do-it-yourself punch repair: is it worth the risk?
Most users are convinced of the inappropriateness of repairing cheap models of rotary hammers. This skepticism is explained by the imperfection of the design of inexpensive, as a rule, Chinese models. But if some minor detail breaks down, this does not mean that you should immediately run to the store for a new tool. Currently, you can easily purchase all kinds of spare parts for any models of rotary hammers.
Another reason for the reluctance to do punch repairs with your own hands is the fear of not understanding the complex mechanism. Of course, such concerns are justified. After all, if the user does not perfectly know the device of the punch, he will not be able to make repairs on his own. In this case, of course, it makes sense to contact a specialized workshop. Be that as it may, do not rush to put an end to your tool, because any repair will be cheaper than a new hammer drill.
Disassembly procedure
If you still decide to repair the punch yourself, then the disassembly of the tool should be done in the following order:
- Carefully remove the shift lever.
- Disconnect the rubber cap.
- Disassemble the cartridge: remove the brushes, unscrew the screws and disconnect the housing.
- Inspect, clean parts, replace faulty elements (brushes, bearings, gears, anchor, etc.), lubricate all friction units (SHRUS lubricants are not recommended).
The tool is assembled in the reverse order.
Symptoms of Failure
But how do you understand that a hammer drill repair is required? Of course, the simplest sign is the inability to turn on the tool. However, you should not ignore any other, even minor changes in the operation of the device. This, for example, may be changes in sounds at idle or during operation, sparks from a motor, smoke, smell of burning, jerking of working bodies, sudden periodic stops, etc. symptoms. All this indicates problems that need to be addressed immediately to avoid global breakdowns and costly repairs.