Abstract: The turbomolecular vacuum pump with active magnetic bearings comprises an enclosure (110) defining a primary vacuum chamber (116), a rotor (120), an electric motor (107), an axial magnetic bearing (103), radial magnetic bearings (101, 102), an axial detector (106), and radial detectors (104, 105). Remote external electric circuits associated with the electric motor (107) and with the axial and radial magnetic bearings (103 and 101, 102) essentially comprise power supply electric circuits (191). Circuits (194) for controlling the axial and radial magnetic bearings (103 and 101, 102) from signals issued by the axial and radial detectors (106 and 104, 105) are embedded in a resin and placed inside the enclosure (110) in the primary vacuum chamber (116). A hermetic leaktight electrical connector (180) and an electric cable (183, 184) providing a connection with the remote external electric circuits (191, 192) each have a number of connection wires that is less than ten.

Abstract: The present invention provides a circuit for monitoring harmonic distortion in the power supply of a synchronous electrical machine with permanent magnet excitation that comprises a rotor without a damper cage, a stator with first, second, and third windings, a frequency converter, and control circuits for controlling the frequency converter.

Abstract: The emergency bearing for a rotary machine having magnetic bearings comprises an emergency landing device including an intermediate element (9) having a large contact area with a stator element (10), the intermediate element (9) being interposed between a bearing member (1, 2, 3) and the stator element (10) fixed to the stator (15) with radial clearance (11, 13) relative to said stator element (10). A damper element (13) acting in the radial direction is interposed between the intermediate element (9) and the stator element (10), and a contact element (14) having very low friction is implemented between the intermediate element (9) and the stator element (10) to reduce friction during rotary movements between these two elements.

Abstract: To eliminate unwanted vibrations caused by synchronous disturbances, such as synchronous disturbances caused by an imbalance, for example, the invention proposes a compensation device for closed loop compensation of a synchronous disturbance in a rotating machine comprising a rotor (64) magnetically suspended by at least one radial magnetic bearing (63) comprising electromagnets (631, 632) driven by amplifiers (61, 62), a radial detector device (633, 634) for sensing the axial position of the rotor, and a closed loop servocontrol circuit connected to said detector device and to said electromagnets and comprising a control circuit (5) for controlling the energization of the electromagnets that supplies a control signal (u) to said amplifiers in response to signals supplied by the detector device to maintain the rotor in a predetermined axial position. The compensation device comprises means (100; 200; 300) for generating a signal for compensating the synchronous disturbance.

Abstract: The rotary machine comprises a rotary shaft (2) supported by first and second radial magnetic bearings (5, 6) that are electrically controlled by a control device (13), said rotary shaft being fitted with an axial abutment device (100) comprising a rotor formed by a disk (101) secured to the rotary shaft (2) and interposed between first and second stators (102, 104) formed annularly around the rotary shaft and each including at least one annular coil (103; 105) controlled electrically by a system for servo-controlling the axial position of the rotary shaft. The stator (104) of the axial abutment device (100) further comprises a secondary induction circuit (106), and the disk (101) secured to the rotary shaft comprises a primary induction circuit (107) so that during rotation of the shaft, electricity is excited in the secondary induction circuit in order to supply energy to the radial magnetic bearings.

Abstract: The active magnetic bearing (1) comprises a stator (2) fitted with electromagnet windings (21) and a first stack of ferromagnetic laminations (22), a rotor (3) fitted with a second stack of ferromagnetic laminations (9), servo-control circuits (10), and position detectors (4, 5, 6). The first stack of ferromagnetic laminations (22) comprises in succession in the axial direction: at least a first sub-set (2a) of laminations (22a) presenting first notches housing electromagnet windings (21); a second sub-set (2b) of laminations (22b) presenting both first notches housing electromagnet windings (21) and second notches housing a radial detector (6); and a third sub-set (2a) of laminations (22a) presenting first notches housing electromagnet windings (21). The first stack of ferromagnetic laminations (22) further comprises fourth and fifth sub-sets (2c) of laminations (22c) at its ends, presenting the same notches as each other and housing respective first and second axial detectors (4, 5).

Abstract: A rotary pump (PP) for taking in a liquid such as a hydrocarbon comprises a pump wheel (1) secured to a rotor (4) which is immersed in a portion of the liquid taken in by the pump. A motor (11) having a stator element (111) mounted in a case (5) and a rotor element (110) mounted on the rotor (4) serves to cause the rotor (4) to rotate about an axis (40). Radial magnetic bearings (7, 8) and axial magnetic bearings (9, 10) support and guide the rotor (4) inside an enclosure (6). A jacket (61) is provided to protect the stator element (111) of the motor (11) from the liquid. The pump is characterized in that the rotor (4) has at least one groove (45, 46) in an outer surface that is covered by the liquid, particularly to reduce the inertial effects due to the liquid.

Abstract: A device for detecting angular position for controlling a synchronous motor with permanent magnet excitation.

Abstract: A device for mounting and driving a tubular spindle (10) has first and second axial-flux radial active magnetic bearings (60, 70) disposed respectively at a first end of the tube (10) and at a second end thereof. Each of the radial active magnetic bearings (60, 70), between which an electric motor (80) is interposed, includes a stator magnetic circuit made up of two subassemblies (61, 62; 71, 72) each of four axial-flux slot-free touching elements distributed around the tube (10). A mechanism is also provided for establishing a reduced pressure, of the order of a few hundreds of Pascals to a few thousands of Pascals, inside the spindle in the air gaps of the radial magnetic bearings (60, 70) and of the electric motor (80).

Abstract: An active magnetic bearing with auto position-detection includes first and second opposing electromagnets disposed on opposite sides of a ferromagnetic body (1) suspended without contract with the electromagnets. The bearing includes inductive type position detectors which are constituted directly by coils (11, 21) of the first and second electromagnets. A mechanism (14; 24) is provided for injecting a sinusoidal current I.sub.0 sin.omega.t of constant amplitude I.sub.0, of angular frequency .omega., and of identical phase, simultaneously to the inputs of power amplifiers (13, 23) powering the coils (11, 21) of the first and second opposing electromagnets in superposition with the main currents from the servo-control circuits (31, 32). Circuits (41 to 44) serve to extract the position information which determines the magnitude of the main current to be applied by the servo-control circuits (31, 32) to the power amplifiers (13, 23) directly from the voltages u.sub.1, u.sub.

Abstract: A vibrator acting in a low frequency vibration domain, for fixing to and applying low frequency vibrations on a frame in a first predetermined direction along an axis X'X.

Abstract: The auxiliary bearing comprises a chromium steel rotor (2) mounted on the rotary shaft (1), a graphite stator (3) mounted on the frame (5) and disposed to face the rotor (2) and to leave clearance relative thereto which is narrower than the air gap in the magnetic bearings which constitute the main supports of the rotary shaft, a network (4) of liquid feed channels opening out into the empty space between the rotor (2) and the stator (3), and selective control means for controlling the supply of liquid through said network of feed channels. The auxiliary bearing may be of the radial clearance type or of the axial clearance type.

Abstract: A combination vibration generator and dampener having magnetic suspension and servo-control along three axes includes a hollow outer body fixed to a structure whose vibration is to be controlled, and an inner body which is essentially spherical in shape and which is inside the hollow outer body. Six active magnetic bearing elements are diametrically disposed in pairs along three orthogonal axes and serve to hold the inner spherical body inside the hollow outer body without direct contact between the inner and outer body. At least three position detectors detect the position of the inner body relative to the hollow outer body while at least one vibration detector device detects vibration forces on the structure whose vibration is to be controlled.

Abstract: The hybrid fluid bearing comprises a fixed body, a tubular part made of a nonmetallic material, mounted inside the body and having an internal bore which defines a cylindrical bearing surface, leaving a small amount of clearance relative to the shaft, which is provided with an annular magnetic circuit constituted by rectified laminations. A fixed magnetic circuit made of laminations defines a series of poles and notches disposed concentrically around the outside of the tubular part, with electromagnetic windings being disposed in the notches around the poles and being fed with electricity from servocontrol loops which receive signals from at least one vibration detector disposed on the fixed body. The cylindrical bearing surface has a series of recesses formed therein, said recesses being distributed around the circumference of the tubular part and being connected to means for feeding them with fluid and for removing fluid therefrom. Sealing means are also provided.

Abstract: The electromagnetic device comprises at least one compensation ring placed in the vicinity of the fluid bearing and mounted relative to the rotor by means of an active radial magnetic bearing whose electromagnet windings are powered as a function firstly of the signals delivered by a position detector for detecting the position of the compensation ring relative to the rotor, and secondly of the signals delivered by at least two vibration detectors disposed on the casing of the machine and having nonparallel sensitivity axes which are perpendicular to the axis of the rotor. The signals delivered by the vibration detectors are applied to a high-gain narrow-band selective feedback circuit whose central frequency is synchronized with a reference frequency fo. The compensation ring is of relatively small mass and serves to exert a rotary compensation force on the rotor via the radial magnetic bearing, which force is equal to the centrifugal force due to the out-of-balance mass of the rotor but which is 180.degree.