# Ultrahigh Vacuum Non-Coaxial Linear-Motion Feedthroughs

• E. A. Deulin
• V. P. Mikhailov
• Yu. V. Panfilov
• R. A. Nevshupa
Chapter
Part of the Fluid Mechanics and Its Applications book series (FMIA, volume 91)

## Abstract

Analysis of linear-motion feedthrough schemes (see Figure 4.2, Chapter 4) shows that sliding speed (V parameter) in kinematic pairs of feedthrough can vary from the maximum value corresponding to the traditional nut-screw couple to zero. The sliding speed variation from maximum value to minimum value leads to a great variation in the design schemes of the feedthroughs. In general, it makes the design of feedthroughs more complex.

One of the ways to decrease sliding speed is the use of bellows sealing elements. These elements directly transmit linear motion fromthe atmosphere into the vacuum chamber. Let us consider the mechanisms of linear motion which correspond to the upper line of Figure 4.2. In the mechanisms of this group, there is no friction in vacuum (Vc = 0). The simplest design of the mechanism consists of one bar sealed with a bellows [1]. The maximum length of the travel depends on allowable strain (stress) in the bellows [1] which can be determined from the following equation:
$$\Delta L = \frac{{\left[ \sigma \right] \cdot n \cdot (1 - \mu )^2 \cdot R_B^2 }} {{E \cdot h \cdot .k_{2B} }}$$
where [σ] is the allowable strain in the bellows; n is the number of crimps; μ is the Poisson coefficient; RB is the internal radius of the bellows; k2B is the coefficient which depends on the goffer depth.

## Keywords

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

## References

1. 1.
Khrunichev Y.A., Deulin E.A., Amosova E.P., Design and Calculation of Vacuum Rotary-Motion Feedthroughs, BMSTU, Moscow, 1977, 56 pp. [in Russian]. Google Scholar
2. 2.
Mednikov M.I., Vacuum Motion Feedthroughs, Machinostroenie, Moscow, 1974, 184 pp. [in Russian]. Google Scholar
3. 3.
Alexandrova A.T., New Methods of Motion Generation and Transformation in Vacuum, High School, Moscow, 1979, 69 pp. [in Russian]. Google Scholar
4. 4.
Novoselov B.V., Bushenin D.V., Mechanical Transmission of Servo-Drive Design (Methodic Recommendations), Vladimir, 1980, 174 pp. [in Russian].Google Scholar
5. 5.
Pinegin S.V., Contact Strength and Rolling Resistance, Machinostroenie, Moscow, 1969, 243 pp. [in Russian]. Google Scholar
6. 6.
Bushenin D.V., Method of rotation movement transformation into linear movement, Soviet Patent No. 271980, 1970 [in Russian].Google Scholar
7. 7.
8. 8.
Demande de Brevet d’Invention No. 7510525. Perfectionnements aux dispositifs de commande, notament de commande etanche d’un mouvement de translation par un mouvement de rotation, Roges Louis Elysel Germain. Date de depot 28 mars 1975.Google Scholar
9. 9.
Bushenin D.V., Non-Coaxial Nut-Screw Drives (Method of Design and Usage), Vladimir, 1974, 104 pp. [in Russian].Google Scholar
10. 10.
Marusov V.A., Mechanisms for linear travel automation in vacuum equipement, Automation of linear travel problems in electronics, in BMSTY Proceedings, Moscow, 1980, Vol. 334, pp. 119–129 [in Russian].Google Scholar
11. 11.
Bushenin D.V., E.A. Deulin E.A., et al., Screw Mechanisms Design (Methodic Recommendation), Vladimir, 1979, 128 pp. [in Russian].Google Scholar

## Authors and Affiliations

• E. A. Deulin
• 1
Email author
• V. P. Mikhailov
• 1
• Yu. V. Panfilov
• 1
• R. A. Nevshupa
• 1
1. 1.Bauman Moscow State Technical UniversityMoskvaRussia