- Aug 23, 2018 -
Electric hammers are a type of electric drill used to drill holes in concrete, slabs, brick walls and stone. This article mainly introduces the structure of the hammer.
The electric hammer is composed of an electric motor, a gear reducer, a crank link impact mechanism, a rotating brazing mechanism, an overload protection device, a power switch, and a power connection device.
The rotary motion of the motor is meshed by the shaft shaft gear, and the eccentric link impact mechanism and the straight bevel gear pair are respectively driven to obtain the required impact work and torque.
The impact motion is driven by the rotation of the motor through the gear to drive the eccentric link mechanism, so that the compression piston reciprocates in the cylinder liner, and an air cushion is generated between the compression piston and the impact piston. Because the impact piston synchronously reciprocates with the compression piston, the tail of the drill pipe is hammered, so that the construction drills the hole. Due to the formation of the air cushion, it also acts as a cushioning force when the whole machine is forced to rebound.
The turning motion is driven by the motor to drive a pair of straight bevel gears, so that the cylinder liner rotates together with the hexagonal sleeve through the load protection device, and transmits torque to the drill pipe. In this way, a combined motion of the impact belt rotation is formed simultaneously with the impact mechanism. The impact is dominant, the rotation is auxiliary, and the hammer is turned again, so that the construction drill advances and gradually becomes the required round hole.
Springs, steel balls, bowl washers, etc. form an overload protection device. When the resistance torque exceeds a certain range (16 ram, 18 mm electric hammer is 15 to 25 N·m, 22 mm, 24 mm electric hammer is 20 to 35 N·m), the torque transmitting sleeve is extruded through its six semicircular recessed holes. The ball causes the steel ball to pop out radially, and the spring is compressed by the bowl-shaped washer to a certain distance, and the sleeve is disengaged from the cylinder liner. At this time, although the motor is rotating, the drill pipe has not rotated. This can be because the concrete is soft and hard, the unevenness is loose or the drill pipe is stuck due to improper use, the operator is sprained and the motor is burned.
The electric hammer is designed with a drill card, which is a device for quick disassembly and assembly of the drill pipe. When loading the hammer bit, simply plug the drill pipe into the hole and the roller can be retracted. At this point, the drill sleeve is automatically reset by the spring, and the roller is pushed into the small diameter of the drill rod to clamp the drill rod. When removing the hammer bit, pull the bit back and pull the rod out.
The electric hammer is designed and manufactured into a class II electric hammer. Additional insulation for the sub-stator, large-size electric hammer (26mmll2 [upper)) Since the motor casing is made of aluminum alloy die-casting, the structure of the insulating bushing is provided in the outer casing and the stator core, and the small-sized electric rust (such as 18 ram or less) A plastic housing structure is used. The additional insulation of the rotor is made of a shaft insulation structure.
The electric hammer's power switch uses a shock-resistant, hand-operated self-locking reset switch.
The soft cable of the electric hammer power cord is made of rubber cable, and the power plug is compression-molded with the rubber sheath soft cable, which is a non-reconnectable power plug.
The drill bit is a working tool for impacting electric drills and electric hammers. The drill bit for impact drill is called "impact drill"; the drill bit for electric hammer is called. Electric hammer drill. The two are collectively referred to as construction drills.
The cutting edges of the construction drills are made of high quality carbide inserts. For impact drilling, tungsten-cobalt-based hard alloys such as YG8 and tungsten-cobalt-based hard alloys such as YG11 for electric hammer drilling. For the drill body material, the impact drill is made of 45 steel or other steel of the same performance. The heat treatment hardness of the handle is not lower than HRC35; for the 40Cr steel for electric hammer drilling, the heat treatment hardness of the handle is not lower than HRC40.