What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Existing wood screws are composed of a threaded portion with a tapered angle and arranged along a tapered stem and a screw head. The head of the screw can be a countersunk head, hemispherical, or other shapes, and the head of the screw has a groove that fits with the tool, a word groove, and a concave cross groove. The taper angle of existing wood screws is either 45 degrees or 60 degrees, and the front end of the taper angle is a pointed point formed by a rotating thread. The existing wood screws have the following three deficiencies in use. Because the taper angle is 45 degrees or 60 degrees, and the thread angle is 71 degrees, the resistance when entering the material is relatively large, so the existing wood screws are manually screwed. It is difficult to screw in, especially when it is used for hardwood materials, and it often happens that the groove of the screw head is screwed out; A large lateral moment will be formed when the screw is screwed, which is prone to the problem of deviation from the position; in addition, because the existing screw is tapered, it will be subjected to both radial force and axial force when entering the material, and its stress state It is more complicated, so it is easy to cause the cracked wood material to burst, and even cause the material to have longitudinal cracks and be unusable.
In view of the above situation, the technical problem to be solved by Guangdong Yueluo Hardware Industry Co., Ltd. is to provide a self-expanding semi-solid installation rivet, the purpose is to solve the existing connection between plastic shells, lightweight plates, insulating materials, circuit boards, or any other In the case of thin, light-weight materials, the grip and bonding force of the rivet itself on the mounting surface is weaker than that of the rivets that are screwed and installed by manual operation. The rivet structure needs to be improved and strengthened when the material is installed.
Existing bolt pairs usually include bolts, nuts and washers, and their specific structures and usage methods are traditionally known and common in life. They will not be described in detail here. You can find relevant bolt pairs by searching for bolt pairs on the Internet. Information picture, the structure of the ordinary bolt pair has basically no structural improvement since it was used as a fastener. The production requirements of ordinary bolt pairs are the basic material, structural strength, and accuracy requirements, while the tightening and anti-loosening requirements The requirements of the effect are basically to achieve the problem of tightening and anti-loosening by using elastic washers, anti-loosening washers or using double nuts.
There are many types of T-bolts used with pre-embedded chutes, which are used for the connection of external components of pre-embedded chutes embedded in segments, U-beams, building concrete, etc. The fixing of the chute on the forming die. When producing segments and U-shaped beams, the embedded chute is fixed on the forming mold by T-bolts. During the concrete pouring process, the tightening nut is easily covered by concrete. In this way, the concrete on the fastening nut should be removed, but it is difficult to remove the concrete, which will cause inconvenience to the disassembly of the forming mold after the production of the segment and the U-shaped beam.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
