As one of the screws, self-tapping screws can directly drill holes on the plate to be fixed by themselves and lock them together with the plate to be fixed. They are easy to use and have a good fixing effect, so they are widely used. However, in the prior art, when the screw is perforated on the plate to be fixed, it is prone to skew, which affects the fixing effect and also reduces the aesthetics. To sum up, how to overcome the above-mentioned defects of the screw fixing method in the prior art is a technical problem to be solved urgently by those skilled in the art.
In the prior art, spring pads are fixed to the seat pan or to the height adjuster tube. However, in the absence of a seat pan, additional components are required to secure the spring pads to prevent movement of the spring pads in the longitudinal direction of the vehicle. FIG. 1 shows such a seat spring pad 2 , which is fixed to the seat pad 1 by means of additional fixing parts 4 . Additional weight is added due to the use of additional fixing parts and a separate step is required in the assembly process to connect the fixing parts to the spring pads. During use, there may be noise between the spring cushion and the seat cushion
GB bolts are generally divided into two types: GB30 bolts and GB21 bolts. The difference is that the hexagonal head of GB30 is larger than that of GB21. The materials are all used: Q235. The grade is 4.8, the hardness is weak, and it is used for parts with low hardness requirements and infrequent activities, which are called ordinary bolts. The most typical use: machinery, construction, fixing, fastening.
The main function of the spring washer is to prevent the nut from loosening. It is also known that: the existing spring washer is a ring made of spring steel, and then a gap is cut in the diameter direction on the ring, and the heads on both sides of the gap are cut. The material of the part is turned to two different sides of the ring to form a pawl, and the purpose of preventing loosening is achieved by the fit between the pawl and the nut on the surface and the workpiece. Obviously, only one pawl is used to achieve the purpose of preventing loosening. Since the braking force generated by one pawl is limited, there are defects of poor braking effect and poor anti-loosening effect.
Length conversion The length of the American screw must be converted to be the metric mm size. Conversion formula: (Length Code / 32) x 25.40 = metric length mm B-3,B-4,B-5 : The marking method is the same as the metric system.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: thin button bolts, GB93b, semi-circular bolts with pads, square gaskets for curtain walls and other products, we can provide you with suitable fastener solutions for you Program.