1. Drill chuck

      Drill chuck is the main accessory of electric drill tools, accounting for 10% - 15% of the cost of electric drill. The development and production of common key drill chuck and light and hand tight drill chuck have also achieved remarkable results.

      An important indicator of hand tight and self tight drill chuck is that the output torque of drill chuck can be more than 90% of its input torque.

      High end drill chucks are mainly used in professional electric tools and bench drills with high requirements. The demand for high-performance self-locking drill chucks and heavy wrench drill chucks is increasing. The high-performance self-locking drill chuck has the characteristics of high precision, high technology content, high added value and high efficiency. It is mainly matched with the impact electric drill of more than 850W and 24V DC in professional electric tools.

      As the quality and performance of electric tools are improving, it is required that drilling operations can be carried out reliably under vibration and impact conditions. Therefore, the matching drill chuck is required to have a locking function to ensure that the tools such as the drill bit held by the electric drill in use are not loose. The global demand for self-locking drill chucks is estimated to be about 19 million by 2010.

      2. Features of high-end drill chuck

      Hand tight and self tight drill chucks have advanced performance. The characteristics of drill chucks include:

      The collet shell is made of engineering plastics, which is light in weight and conducive to environmental protection; There are also metal chucks with high strength and rigidity; The coaxiality of the collet is very high, ensuring the machining accuracy; The top of the collet is equipped with a hexagon head, which is very easy to install, fasten and disassemble the collet   

      The top of the chuck is provided with a rotary dust boot, which can prevent dust and sundries from being embedded into the chuck during operation and can be used by the operator to support the chuck to make it work more stably; The gripper is specially hardened and has extremely high strength. When the drilling force is too large, the drill rotates in the gripper, but the gripper will not be damaged

      The collet has the function of clamping force signal. When the drill bit is clamped or working, when the clamping force reaches a certain value, the clamping head makes a "click" sound, which tells the user that the drill bit has been completely clamped, and the tool can be used safely. With the increase of the clamping force, the drill can make three "clicks", corresponding to three different clamping forces. The drill can be used safely under any of the three clamping forces.

      This kind of clamping force signal can make the drill chuck work in the best clamping force and safe state, and can greatly extend the life of the chuck. Moreover, the clamping force signal can give users a very good feeling, making it extremely easy to judge whether the chuck has reached the optimal clamping force and safe state, thus avoiding the accidents of insufficient clamping force, bit slipping and excessive clamping force damaging the bit.

      The collet is also provided with a dust hole, which can leak the dust and sundries embedded in the collet during the working process, thus ensuring the operability of the tool and extending the service life of the collet and the drill bit.

      Standard system of electric tools, a standard system combining comprehensive standardization and hierarchical structure with products as the leader and safety standards and electromagnetic compatibility standards as the main body, electromagnetic compatibility standards, technical management standards, product standards, parts and accessories standards, process standards and relevant standards.

      (1) Electromagnetic compatibility standard

      Electromagnetic compatibility refers to the ability of products to work normally in their electromagnetic environment without causing unbearable electromagnetic interference to anything in the environment.

      International: The European 89/336/EEC Electromagnetic Compatibility Directive came into force on January 1, 1996, implementing the licensing system and conducting EMC certification.

      China: GB4343-1995 Measuring Methods and Allowable Values of Radio Characteristics of Electric and Electric Heating Appliances, Electric Tools and Similar Electrical Appliances for Household and Similar Purposes.

      (2) Safety series standards

      The safety series standards for electric tools are the key implementation projects of the mechanical industry standards and the basis for the safety certification and product quality supervision and spot check of electric tools. As of September 2001, 77 enterprises, more than 300 electric tools and accessories products have passed the certification and obtained the "Great Wall" mark. The output of certified products accounts for more than 90% of the total output of the industry.

      (3) GB3883 Safety of Hand held Electric Tools series of national standards. It consists of 18 items and 27 sub categories of product requirements and general safety requirements.

      (4) IEC745 standard of International Electrotechnical Commission.