Abstract: A turbomachinery includes a labyrinth seal (2) to prevent unstable vibration of a rotor formed by dividing the seal into segments (7) in a circumferential direction and combining the segments (7) whose comb teeth (5) differ in height. The labyrinth seal (2) preferably includes two kinds of segments (7) whose comb teeth (5) differ in height for each kind of segment, and the segments (7a) of the greater comb tooth height are arranged in a certain reference direction on a cross section right-angled to a rotational axis, and in a direction opposite to the reference direction, and the segments (7b) of the smaller comb tooth height are arranged in a direction right-angled to the reference direction, and in a direction opposite to that right-angled to the reference direction.

Abstract: A labyrinth seal is provided that can suppress the occurrence of an unequal pressure pattern in the seal, suppress unstable vibration of a rotating shaft and ensure sealing performance. The labyrinth seal includes a seal ring 13 and a plurality of seal fins 11. Ring-like cavities 12 are defined on the outer circumference of the rotating shaft 2 with the seal ring 13 and the seal fins 11. The ring-like cavities 12 suppress a leakage flow LS moving along the outer circumference of the rotating shaft 2. Void portions 14 are each provided on the outer circumferential side of the cavity 12 in the seal ring 13 so as to extend in the circumferential direction of the rotating shaft 2 and communicate with the cavity 12 at circumferential intervals to temporarily relieve a leakage flow from inside the cavity in the circumferential direction.

Abstract: Disclosed herein is a turbomachinery including a labyrinth seal easy to fabricate and adapted to prevent unstable vibration of a rotor. A turbomachinery according to this invention includes a labyrinth seal 2 formed by dividing the seal into segments 7 in a circumferential direction and combining the segments 7 whose comb teeth 5 differ in height. The labyrinth seal 2 preferably includes two kinds of segments 7 whose comb teeth 5 differ in height for each kind of segment, and the segments 7a of the greater comb tooth height are arranged in a certain reference direction on a cross section right-angled to a rotational axis, and in a direction opposite to the reference direction, and the segments 7b of the smaller comb tool height are arranged in a direction right-angled to the reference direction, and in a direction opposite to that right-angled to the reference direction.

Abstract: The vibration and noise excited by the electromagnetic exciting force in the radial direction of an electric motor are suppressed. In an electric motor 100, a rotor 1 is divided into four rotor pieces 3, 4, 5, and 6 for an axial length of 2L of one group of the rotor core, and for example, the four rotor pieces 3, 4, 5, and 6 are ideally 0.29L, 0.71L, 0.71L, and 0.29L in axial length in the axial direction, and permanent magnets 2 of the rotor pieces 3, 4, 5, and 6 are arranged in the circumferential direction so that the phase differences of the electrical angle are 0, ?, 0, and ?. Further, when an effect is obtained even if the ideal axial length is changed, the tolerance of the aforementioned axial length is ±0.1L.

Abstract: The vibration and noise excited by the electromagnetic exciting force in the radial direction of an electric motor are suppressed. In an electric motor 100, a rotor 1 is divided into four rotor pieces 3, 4, 5, and 6 for an axial length of 2L of one group of the rotor core, and for example, the four rotor pieces 3, 4, 5, and 6 are ideally 0.29L, 0.71L, 0.71L, and 0.29L in axial length in the axial direction, and permanent magnets 2 of the rotor pieces 3, 4, 5, and 6 are arranged in the circumferential direction so that the phase differences of the electrical angle are 0, ?, 0, and ?. Further, when an effect is obtained even if the ideal axial length is changed, the tolerance of the aforementioned axial length is ±0.1L.

Abstract: In a fluidal machine with an impeller rotating to urge a fluid radially outwardly by a centrifugal force, a vane guiding the fluid discharged from the impeller, a vane member which includes a front end of the vane facing to the impeller so that the fluid discharged from the impeller strikes against the front end and which is prevented from contacting the atmosphere, and a casing surrounding the vane member and contacting the atmosphere, the vane member is discrete from the casing, a vibration propagation between the vane member and the casing is prevented or restrained, and a vibration of a pipe extending from the casing is absorbed.

Abstract: In a fluidal machine with an impeller rotating to urge a fluid radially outwardly by a centrifugal force, a vane guiding the fluid discharged from the impeller, a vane member which includes a front end of the vane facing to the impeller so that the fluid discharged from the impeller strikes against the front end and which is prevented from contacting the atmosphere, and a casing surrounding the vane member and contacting the atmosphere, the vane member is discrete from the casing, a vibration propagation between the vane member and the casing is prevented or restrained, and a vibration of a pipe extending from the casing is absorbed.

Abstract: In a fluidal machine with an impeller rotating to urge a fluid radially outwardly by a centrifugal force, a vane guiding the fluid discharged from the impeller, a vane member which includes a front end of the vane facing to the impeller so that the fluid discharged from the impeller strikes against the front end and which is prevented from contacting the atmosphere, and a casing surrounding the vane member and contacting the atmosphere, the vane member is discrete from the casing, a vibration propagation between the vane member and the casing is prevented or restrained, and a vibration of a pipe extending from the casing is absorbed.

Abstract: A band pass filter multiplies an input waveform with first trigonometric functions at a plurality of frequencies and then filters the products. Furthermore, with that filtering step, the products are multiplied, or their phase is changed by a predetermined value, and the results are multiplied by the inverse of the trigonometric functions.The sum of this, for all frequencies, generated a filtered output waveform. Where the input waveform has two components, the corresponding outputs can be obtained from the read and imaginary components of the output waveform. In practice the trigonometric functions are produced by sine and cosine components at each frequency. In this way a band pass filter device is formed which is suitable for use in the control system of an apparatus which must be controlled continuously, such as a control system for a rotor.

Abstract: In an electromagnetic bearing control apparatus for suppressing vibratory rotational motion of a rotor, a selective extraction unit is provided in servo-circuits which control currents being supplied to electromagnetic coils in accordance with x and y-component signals of radial displacement of the rotor such that the rotor is held in a predetermined radial position, and x and y-component signals delivered out of the selective extraction unit are crossed and inputted to the servo-circuits so as to be added in opposite polarities to processed x and y-component signals of radial displacement.

Abstract: The present invention reduces the resonance amplitude of the rotational frequency-synchronous unbalance vibration of a rotor supported by an electromagnetic bearing.To this end, the invention disposes an X-direction control servo circuit and a Y-direction control servo circuit each of which detects the deviation of the rotor from a desired position in the radial direction thereof and controls the rotor so as to be held at the desired position on the basis of the detection signal, and a tracking filter which is synchronous with the rotational frequency. Outputs from the filter are crossed to supply the Y-direction control servo circuit with the X-directional output and to supply the X-direction control servo circuit with the Y-directional output signal.

Abstract: An axial thrust balancing system including a sleeve for balancing an axial thrust applied to a rotary shaft and a bush defining therebetween a clearance having arranged therein at least one pressure chamber for dividing the clearance into a plurality of smaller clearances. The axial division of the clearance reduced the ratio of the axial length of the clearance to the diameter of the sleeve and stabilizes the bearing characteristics of a film of fluid in the clearance, thereby inhibiting the generation of a self-excited vibration of the shaft up to a high rotation velocity.