What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
In CN203807560, nails and bolts are used to connect the plates, but the heads of the nails and the bolts are enlarged ends that are wider than the rods, and the heads of the nails and the bolts cannot penetrate into the interior of the door body, so in terms of appearance, the more More nails and bolts will leave more spots on the surface of the door that are not suitable for the door itself. In the prior art, the treatment method for these spots is generally to paint with paint, which can only make the door panel consistent with the head of the nail and the bolt in color, but cannot change the shape of the head of the nail and the bolt, and the appearance is still good. Obvious spots were noticed, which made the door panels connected by nails and bolts to the panels, which could not be used as door panels for household doors.
Blind rivets (blind rivets) --------- rivet body (rivet body) mandrel (rivet stem or rivet mandrel). It is a type of rivet for single-sided riveting, but it must be riveted with a special tool - a rivet gun (manual, electric, pneumatic). When riveting, the rivet core is pulled by a special rivet gun to expand the rivet body and play a riveting role. This type of rivet is especially suitable for riveting occasions where it is inconvenient to use ordinary rivets (riveting from both sides), so it is widely used in construction, automobiles , ships, aircraft, machinery, electrical appliances, furniture and other products. Among them, the open-type oblate head blind rivets are the most widely used, the countersunk head blind rivets are suitable for riveting occasions where the surface needs to be smooth, and the closed blind rivets are suitable for riveting occasions that require high load and certain sealing performance.
A double-nut self-locking fastener includes bolts, nuts, nuts, and elastic gaskets that can produce plastic deformation under pressure; the nut and the bolt are connected by threads, and one end of the nut is provided with an external thread; There is an inner thread in one end, and the inner thread of the nut and the outer thread of the nut constitute a thread pair; the other end of the nut is provided with a through hole, and the bolt passes through the through hole of the nut; when the nut and the nut are installed and tightened, the elastic gasket is located in the nut. between the bolt and the nut; a notch for cutting off the thread is arranged on the circumference of the bolt thread; the direction of the notch is parallel to the axial direction of the bolt.
The elastic cylindrical pin, also known as the spring pin, is a headless hollow cylindrical body, which is slotted in the axial direction and chamfered at both ends. It is used for positioning, connection and fixation between parts. The outer diameter of the spring pin is usually slightly larger than the mounting hole. The deformation force generated by the elastic cylindrical pin to be restored to its original state by extrusion ensures the clamping effect of the elastic cylindrical pin. But just because of its clamping effect, it will play a big obstacle to the disassembly of the elastic cylindrical pin. When in use, the open end is extended out of the through hole on the pin shaft, and the open end is flared and separated to prevent the elastic cylindrical pin from sliding off the pin shaft to realize the function of preventing backlash. At present, the disassembly method of the elastic cylindrical pin usually uses a punching machine to remove the cylindrical pin, which easily destroys the equipment installed on the cylindrical pin, and the disassembled elastic cylindrical pin cannot be used again due to damage. One method is to insert the mounting pin with the clearance fit of the mandrel, punch the pin behind the mandrel to clamp the bottom of the cylindrical pin, and then pull out the cylindrical pin, which can only be used when the elastic mounting pin is installed in the through hole, and because it is necessary Applying force to the mandrel increases the difficulty of disassembly and increases the work intensity of the installer. Three methods are done by the installer using two needle nose pliers. Specifically, first use needle-nose pliers to clamp the ends of both sides of the elastic cylindrical pin, and then apply an inward force to the needle-nose pliers, so that both sides of the elastic cylindrical pin rotate in the same direction until the opening becomes smaller, and then Pull it out to remove it successfully. The defects of these existing methods are obvious. The shape of the disassembled elastic cylindrical pin is either unusable or the deformation of the cylindrical pin after disassembly is not uniform, which seriously affects the performance of the elastic cylindrical pin, resulting in waste and increased cost; The method is purely manual work, and sometimes it takes several repetitions to remove the elastic cylindrical pin. Due to the different installation positions of the elastic cylindrical pin, it sometimes increases the difficulty of disassembly, and it is difficult to remove the needle-nose pliers effectively. The pliers are difficult to construct, and the elastic cylindrical pins are easily damaged. If there are too many elastic cylindrical pins to be disassembled, the existing methods are often difficult to meet the needs, which not only consumes a lot of time and physical strength of the installer, but also makes it difficult to ensure the quality.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
