The construction principle of the electric hammer drill

<p>(1) Structure and principle: The electric hammer drill is composed of a drill bit, a chuck, a roller, an adjustment sleeve, a transmission system (including an electric gas turning device, an impact piston, a hammer body, a mechanical overload protection device and various speed change gears), a motor, The shell, control switch and working state control valve (stop) are composed. The motor provides rotating energy, and part of the energy drives the piston to make a complex movement of the column through the variable speed gear, crank wheel, and connecting rod. It cooperates with the impact piston to produce a high-pressure air cushion that changes periodically, and drives the impact piston to make the complex impact hammer body. The movement drives the drill bit to impact; the other part of the rotating energy drives the chuck and the drill bit to rotate through the overload protection device, the fence change ring and so on. The working form of the tool is controlled by the gear lever, and the gear gear clutch and the action of the impact piston can be adjusted by turning the gear lever, so that the tool can complete single-rotation transmission, single-stroke and rotation plus impact.</p><p><br></p><p>(2) Operation and use: select the applicable drilling rig and drill bit according to the internal customer, and ensure that the drill bit is complete, the tool performance is good, and the power supply is consistent with the tool specification. Ensure that the quality of the lubrication and cooling sleeves is up to standard. Make sure that the drill bit and chuck are free of impurities and dust. Apply a small amount of grease to the shank of the drill bit and insert it into the hole of the front cover. The specific model is according to the instruction manual of the tool, and the gripper is turned to fasten the drill bit on the drill rig. Move the lever to the selected gear. Put the top of the drill bit into the drilling or gouge position, lightly press, hold firmly, stand firm, and turn on the control switch. The hammer drill only needs to be pressed a little, and the chips can be discharged freely without pushing hard. Especially in the drilling and crushing operations, the use of machine weight work without heavy pressure. </p><p><br></p><p>(3) Specifications and selection: There are many types of <a href="https://www.worksitetool.com/cordless-impact-drill.html" rel="noopener noreferrer" target="_blank">electric hammer drills</a>, among which imported equipment has better performance, but the price is higher. When choosing, it should be based on the size of the workload and the ability to self-drain. Under normal circumstances, the technical performance of the electric hammer changes according to the input power, that is, the greater the power, the stronger the drilling and drilling capabilities, and the corresponding increase in weight. Therefore, comprehensive consideration should be taken when selecting. In addition, it is better to make the processing capacity of the tool slightly larger than the work requirements. In general, the tool should be operated in the state of 80%-90% of the processing limit to avoid the tool running at full load for a long time and reduce the service life. </p><p><br></p><p>(4) Selection of drill bits and chisels: There are many types of drills and chisels that can be equipped with electric hammer drills. Tungsten carbide cement drills, tungsten carbide cross drills, sharp chisels, dry chisels, and gouges are often used. Tungsten carbide cement drills are mainly used for drilling of various strength grades of concrete. The most commonly used specifications are drill holes with diameters of 5 to 38. Tungsten carbide cross drills are mainly used for drilling of various bricks and slightly lower strength concrete. The processing aperture is large, and the power of the tool is also large. The usual specifications are 30 to 80 holes in diameter. Sharp chisels are usually used for crushing, dry chisels are used for roughing, and trench chisels are used for slotting. Hollow drills are used less frequently and can be used to drill large holes. Their specifications are 40-125mm.</p>