The ball screw pair of Shenyang Machine Tool Works is the same as other rolling friction transmission parts. As long as the addition of abrasive particles and chemically active substances is avoided, it can be considered that these components are almost working under the condition of wear and tear. However, if stolen goods are dropped on the raceway or dirty lubricating oil is used, it will not only hinder the normal movement of the mixing, but also cause a sharp increase in wear. For ball screw drive pairs with CNC manufacturing errors and preload deformations measured in microns, this kind of wear is particularly sensitive, so it is very necessary to effectively protect, seal and keep the lubricating oil clean.
Usually a felt ring is used to seal the nut. The thickness of the felt ring is 2-3 times the pitch, and the inner hole is made into a threaded shape to make it tightly wrap the lead screw and fit it into the slot at both ends of the nut or sleeve . In addition to the use of soft felt for the sealing ring, oil-resistant rubber or nylon materials can also be used. Since the seal ring and the screw are in direct contact, the dust collection effect is better, but the friction resistance torque of the ball screw pair is also increased. https://cncmachiningservices.cn/In order to avoid this frictional resistance moment, a non-contact labyrinth seal ring made of hard plastic can be used. The inner hole is made into the opposite shape of the screw thread raceway, and a certain gap is left.
For the exposed screw, spiral steel belts, telescopic sleeves, tapered sleeves, and partial protective covers of folding plastic or artificial leather are generally used to prevent dust and abrasive particles from adhering to the surface of the blade screw. These types of protective covers are similar to the protective covers of the guide rail. One end is connected to the end face of the ball nut. The principle is shown in Figure 3.28. https://whatiscasting.com/The protective device and the nut are fixed on the pallet together, and the steel belt in the whole device is composed of parts such as the supporting roller, the tensioning wheel and the steel belt. The two ends of the steel belt are respectively fixed on the outer circular surface of the lead screw. The steel belt in the center of the protection goes around the supporting rollers, and the steel belt is tensioned by springs and tensioning wheels.
When the lead screw rotates, the pallet (or table) moves axially relative to the lead screw. The steel belt of one section of the lead screw is released according to the pitch of the lead screw, and the other section is wound around the steel belt with the same pitch. On the screw. Since the width of the steel strip is exactly equal to the pitch of the screw, https://hotchamberdiecasting.com/the thread groove is tightly sealed. Because the front and back sides of the steel belt are not in contact at all times, the dirt on the outer surface of the steel belt will not be brought to the inner surface, so that the inner surface is kept clean.