Linear Motion: Ball Screws
116Pages

NTN-SNR LINEAR MOTION: NTN BALL SCREWS

NTN-SNR THE STRENGTH OF A GROUP We are one of the largest bearing manufacturers in the world in conjunction with the Japanese company NTN. NTN-SNR has been established in the linear technology market since 1985 and strives to offer a complete and competitive product range. This position allows us to provide our customers with a high level of added value regarding service, quality and product variety. Our sales support and applications engineers are always on hand to offer you optimal support. Our sales and application engineers are always available. The consulting and planning service is...

SNR Ball Screws are universal machine elements that meet the constantly growing demands on the automation of assembly and manufacturing processes. NTN - SNR produces one of the widest product ranges of Ball Screws. SNR Ball Screws are used in many different applications, such as: • Machine tools • Packaging and printing machines • Special and general engineering • Aircraft construction • Automation and assembly lines • Wood and paper industry • Semiconductor industry • Medical engineering • and such more Advantages: • Wide range of rolled, whirled and ground Ball Screws • Different nut...

Content 1.______ Ball Screw basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.______ System technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1_________ Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2_________ Used standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3_________ Intended use. . . . . . . . . . . . ....

5.______ SNR Ball Screws. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1_________ Versions and options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.1_______ Nut types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2_______ Main parameter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.3_______ Correction factors for load...

Ball Screw basics Design principles of Ball Screws Ball screw drives are among the most important drive elements for mechanical engineering in linear technology. These drive units consist of a threaded spindle with end machining for the bearings, the ball screw nut with balls, a ball deflection system and sealing elements as well as the bearing units (Figure 1.1). 1 Drive journal 2 Bearing unit (floating or fixed bearing), here fixed bearing 3 Threaded shaft 5 Bearing unit (floating or fixed bearing), here floating Figure 1.1____ Construction of a Ball Screw drive Ball screw drives are used...

Depending on the diameter, pitch and ball size, the threaded spindles can be manufactured as single or multi threaded spindles as well as with right or left-hand helix. The dimensions shown in Figure 1.3 are important for the designation and technical design of Ball Screws Figure 1.3____ Design measures of Ball Screws The size specification of a ball screw is usually made up of the nominal diameter and pitch, although the nominal diameter cannot always be measured directly on the threaded spindle, depending on the manufacturing process. Manufacturing processes of Ball Screw shafts Ball...

1.2.2 Whirling Whirling is a machine cutting process with geometrical defined cutting edges 1 . In this process, the very fast, eccentric rotational movement (nwz) of the tool 2 is superimposed on a slow rotation (nws) and feed movement (v1) of the threaded spindle 3 (Figure 1.5). The whirling tool 2 is inclined by the angle α. Depending on the whirling machine used, hardened and non-hardened shafts can be used as the raw material. It is a very flexible manufacturing process with which single-threaded spindles can be manufactured in almost all combinations of spindle diameter, pitch, ball...

1.3 Features 1.3.1 Efficiency Due to the use of rolling balls as transmission elements between the threaded spindle and the nut, Ball Screws are characterized by a very high degree of efficiency. Compared to trapezoidal spindles, the drive torque can be reduced by up to 75%. For this reason, ball screws can convert not only rotary movements into linear movements (Figure 1.7), but also linear movements into rotary movements (Figure 1.8). Ball Screw µ=0,01 Trapezodial Screw µ=0,1 Figure 1.7____ Efficiency when converting rotary to linear movement Ball Screw µ=0,01 Trapezodial Screw µ=0,1...

Typical design typs of Ball Screw nuts are flange nuts (Figure 1.9), cylindrical (Figure 1.10) and screw-in nuts (Figure 1.11). Figure 1.9 ___ Flange type nut Depending on the size and series, flange nuts, but also partly cylindrical nuts, can be designed as single nuts (Figure 1.12), single nuts with pitch offset (Figure 1.13) or double nuts (Figure 1.14). Figure 1.12 ___ Single flange type nut Figure 1.13___ ingle flange type nut wit S pitch offset Figure 1.14 ___ Double flange type nut Depending on the installation space, flange type nuts can be designed in three flange types (Figure...

Ball deflection types The balls in Ball Screws move in one or more closed ball circuits. The power transmission takes place in the loaded area in which the balls are in contact with the nut and the threaded spindle. The total number of revolutions of the balls around the threaded spindle in the loaded area indicates the number of revolutions. The balls are unloaded in the ball deflection. The balls can be deflected in different ways. The ball deflections are divided into internal and external deflections as well as single and multiple deflections. Internal deflection The most common...