Abstract: A clamp for a male terminal of a power source, the terminal including a frustoconical body projecting out of a base surface that is part of the source against which a greatest diameter of the terminal rests, may include: at least one ring-shaped first portion, with an open section of its circumference, the at least one first portion having a first diameter such that a predetermined radial clearance exists when the at least one first portion axially fits upon the frustoconical body, the at least one first portion also having two jaws which axially project out of the circumference of the at least one first portion, the jaws being in opposed, spaced-apart relationship; and a clamping device which acts on the jaws and is configured to move the first jaws toward each other to tighten the at least one first portion around the frustoconical body with elimination of the clearance.

Abstract: A clamp for a male terminal of a power source, consisting of a frustoconical body projecting out of a base surface that is part of the source against which it rests with its greatest diameter. The clamp comprises at least one first ring-shaped portion with an open section of its circumference. Said first ring-shaped portion has such a diameter that a predetermined radial clearance exists when it axially fits upon said frustoconical body, and also has two jaws which axially project out of its circumference and are located at the ends of the open section of the circumference. The jaws are in opposed, spaced-apart relationship and a device is adapted to cause them to move toward each other to clamp the ring-shaped portion around the frustoconical body, by eliminating the radial clearance.

Abstract: A rotary vacuum pump, for instance a vane pump, has at least one circumferential groove (6) between facing side surfaces of the rotor (2) and of the rotor guide (3) for receiving a lubricating and sealing fluid. The circumferential groove (6) is a partial annular groove, which has an angular extension of less than 360° and has at least one interruption enabling creating a hydrodynamic fluid bearing in a region opposite a discharge region of the pump (1; 101; 121; 201), over the whole axial extension of the facing surfaces. A method of lubricating a rotary vacuum pump is also provided.

Abstract: A rotary vacuum pump, for instance a vane pump, has at least one circumferential groove (6) between facing side surfaces of the rotor (2) and of the rotor guide (3) for receiving a lubricating and sealing fluid. The circumferential groove (6) is a partial annular groove, which has an angular extension of less than 360° and has at least one interruption enabling creating a hydrodynamic fluid bearing in a region opposite a discharge region of the pump (1; 101; 121; 201), over the whole axial extension of the facing surfaces. A method of lubricating a rotary vacuum pump is also provided.

Abstract: A rotary vacuum pump comprises, between the rotor (2) and a driving motor, a control unit (1; 101) for operatively connecting the pump and the motor only in the periods in which the pump operation is required or desired.

Abstract: A rotary vacuum pump comprises, between the rotor (2) and a driving motor, a control unit (1; 101) for operatively connecting the pump and the motor only in the periods in which the pump operation is required or desired.