| 摘要 |
<p>An improved getter pump, particularly suitable for use in a vacuum device wherein it is necessary to minimize the volume taken up by the on-site pump and the heating power it requires, includes, around a known assembly of getter elements (1) mounted on a sheath (20) which houses a heating member (2), a plurality of tubular metallic shields (7, 8, 9) coaxial with one another and with said heating member, preferably in the number of three. Said tubular shields are secured at one closed end thereof to a base support (6), and at the other end they communicate with the space to be evacuated through two metallic nets (17, 18) at the two innermost shields (7) and (8), whereas the outermost shields (if they are more than two) of larger diameter are free at said end. The outermost net (18) is preferably more close-meshed and formed by thinner metallic wire with respect to the inner net (17). <IMAGE></p> |
