55results about How to "Avoid abnormal vibration" patented technology

The moment of inertia and the eccentric load are measured in rotating a drum at 100 rpm, and the decision critical value is decided according to the moment of inertia and the eccentric load(S31-S42). The motor is controlled to accelerate within the range of 140 to 220 rpm less than the resonance point of about 250 rpm, and the value is measured according to fluctuation of acceleration(S43-S47). The large vibration is decided, and the emergency stop is performed in case of the value from the acceleration fluctuation to be over the critical value(S48). Acceleration is changed by adding uneven load to the bearing in rotating while reducing eccentric load, and the critical value is decided accurately according to the moment of inertia and the eccentric load.

The invention provides a washing machine for an electric detection for the weight unbalance owing to deflection of the washings to one side or the like, wherein the abnormal vibration of the longitudinal shaking is detected by a first detection mechanism and a second detection mechanism and the abnormal vibration of the transverse shaking in the high speed rotation is detected by a third detection mechanism. The first detection mechanism determines whether a washing dewatering tank has the unbalance by comparing a difference of the rotation speed at a prescribed interval and a prescribed threshold when the rotation speed of a motor is increased to a low speed superior target rotation speed. The second detection mechanism determines whether the washing dewatering tank has the unbalance by comparing a difference between a duty ratio reduction and the reference duty ratio reduction and the threshold, wherein the duty ratio is used for maintaining the low speed superior target rotation speed. In the third detection mechanism, the change of the duty ratio in the high speed rotation is observed and threshold is switched based on the reference duty ratio so as to stop control of the motor.

A washing machine and a control method thereof sensing an unbalance condition occurring during a spin-dry cycle. The washing machine includes a controller controlling a speed of a motor in accordance with a weight of laundry contained in a rotating tub, upon wrapping the laundry at an initial stage of the spin-dry cycle. A gradient of the motor speed in a laundry wrapping process is determined, depending on the weight of the laundry. Accordingly, to greatly reduce a time prior to a main spin-dry process is possible, while preventing abnormal vibrations from being generated when a rotating speed of the rotating tub reaches a speed, at which resonance occurs.

A vehicle brake apparatus capable of preventing abnormal vibration due to thickness variations in a disc rotor includes a motor drive unit configured to control the motor which presses the brake pad against the disc rotor, a brake pressure detection unit for detecting a braking pressure for pressing the brake pad, and a wheel speed sensor for detecting a rotation speed of the disc rotor. If an amount of variation in the detection values detected by the brake pressure detection unit during one rotation of the disc rotor exceeds a variation amount determination threshold value and a detection value variation frequency has a correlation with the rotation speed of the disc rotor and the detection value variation frequency exceeds a variation frequency determination threshold value, the motor drive unit controls the motor in inverted phase to the variation in the detection values.

The invention discloses a method and device for weighing clothes in a washing machine, and relates to the technical field of washing machines. The method comprises the steps that when a motor rotates, the transient angle of flow of the motor is calculated; according to the transient angle of flow of the motor and a characteristic curve of motor power signals, transient power consumed by the motor is calculated; integral summation is carried out on the transient power consumed by the motor, and work of the motor on clothes is obtained; according to the corresponding relation of the magnitude of the work and the weights of clothes, the clothes weight corresponding to the work which is done to the clothes by the motor is searched for. The clothes in the washing machine can be weighed through software, extra hardware detection circuits are not needed, and product cost reduction is facilitated.

The invention relates to the technical field of clothes washing, in particular to a drainage abnormity detection control method for a washing device, and a washing device, and aims to solve the problem that an existing washing device cannot accurately determine whether drainage is abnormal or not. For this purpose, the drainage abnormality detection control method comprises the following steps: under the condition that the washing device executes drainage operation, acquiring the drainage speed of the washing device; and determining whether the washing device is abnormal or not according to the drainage speed. The washing device comprises a control device used for executing the drainage abnormity detection control method. According to the invention, whether the washing device is abnormal or not is determined accurately according to the drainage speed, and the dewatering of the washing device is prevented due to abnormal drainage, the abnormal vibration caused by dewatering in the washing device is avoided, the probability of abnormal vibration of the washing device is reduced, and the use experience of the user is improved.

The invention aims to provide a centrifugal refrigerator having high pressure head specification. The centrifugal refrigerator can avoid surge, and the capacity of the refrigerator can be reduced to the load capacity on the equipment side during low pressure head. The centrifugal refrigerator comprises a measuring unit, an economizer steam valve (7) and a control device (20), wherein the measuring unit is used for measuring the pressure difference between a condenser (4) and an evaporator (5); the economizer steam valve (7) is arranged on a flow path (11) and used for opening and closing the flow path (11), and the flow path (11) is used for communicating an economizer (6) with the middle part of multiple compression stages of a multi-stage centrifugal compressor (TC); the control device (20) controls the opening of a guide vane which is used for adjusting the flow of suction facing the multi-stage centrifugal compressor (TC), and controls the lower limit of opening of the guide vane variably on the basis of the relationship between the preset pressure difference of the condenser (4) and the evaporator (5) and the lower limit of opening of the guide vane according to the pressure difference measured by the measuring unit.

The invention discloses a washing machine and a method for balancing clothing, wherein in the dewatering procedure of the washing machine, at least two clothing balancing modes are set according to the water absorption rate eta of the clothing to be washed. In addition, the method for balancing the clothing comprises the following steps: S1, acquiring the non-immersed weight m and immersed weight n of the clothing to be washed, and deriving the water absorption rate eta of the clothing to be washed; S2, calling the clothing balancing mode corresponding to the absorption rate eta, and executing the clothing balancing mode; and S3, after the clothing balancing mode ends, performing high-speed spinning dewatering in an inner cylinder. Through the above technical scheme, the condition that the clothing is concentratedly accumulated in a certain position in the inner cylinder when dewatered and forms imbalance which causes the consequence that the whole outer cylinder generates abnormal vibration and noise is avoided, and simultaneously, because clothing balancing is completed before high-speed dewatering, power consumption in the process of dewatering of the washing machine is saved, convenience is brought to users and the user experience is further improved.

Provided is a technique which can prevent abnormal vibrations from occurring on a resonator and apply, to a cutting edge, vibrations with the magnitude of amplitude thereof adjusted in the direction of width of the edge, thereby cutting an object of interest with high accuracy. The resonator (21) with a grip portion grasped with clamp means (28) is supported by a support means (24), thereby preventing abnormal vibrations from occurring on the resonator (21). The resonator (21) has at least one elongated hole (26b) defined through a side thereof, thus allowing for adjusting the amplitude magnitude of vibrations in the direction of width of the cutting edge (23) on one end of the resonator (21). This enables vibrations with the amplitude of an adjusted magnitude in the direction of width to be applied to the cutting edge (23). Accordingly, the cutting edge (23) which is adequately vibrated can be used to cut the object of interest with high accuracy.

The invention discloses a portable transformer substation noise imaging positioning detection device which comprises an imaging displaying mechanism and a noise detection mechanism which are connected via a coaxial cable, the noise detection mechanism comprises a noise sensor of which a matrix is arranged on a quadratic surface structure and a signal pre-treatment circuit; the imaging display mechanism comprises a display, a processor and a data memory connected with the processor; the processor is provided with a sound intensity mapping processing module for driving and displaying a sound intensity mapping figure to quickly judge a noise resource. According to the position of equipment to be detected in a transformer substation, a cubic data module of a quadratic surface is established, a three-dimensional coordinate system is established on the basis of the cubic data module, and pre-treatment and pre-displaying of a relative noise signal are performed, spurious imaging information is used for noise imaging, and quick fault positioning is achieved by analyzing a color ring band. The portable transformer substation noise imaging positioning detection device effectively improves the efficiency of overhauling and maintaining the transformer substation, is simple, convenient and practical, and has very high promotion and application values.

The invention provides a low-noise deep groove ball bearing. A bearing retainer (6) formed by mutually buckling two parts is distributed in a cavity between a bearing inner ring and a bearing outer ring, the combination position of the bearing retainer (6) among bearing balls (3) uses a tenon and groove combination form, the bearing retainer (6) is in an axial direction between the bearing inner ring (1) and the bearing outer ring (2), two side parts of the spherical cavity form two annular slots (6.2, 6.4), and the openings of the two slots are open to a baring ball raceway and are divergent.

The invention discloses a method for reminding a user to dismantle a package bolt, relating to the technical field of washing machines. The method for reminding the user to dismantle the package boltcomprises the following steps: a reminding module reminds the user to dismantle the package bolt at least one time after the washing time is started. After the washing machine is started certain time,the reminding module reminds the user to dismantle the package bolt. After the user dismantles the package bolt, great noises or abnormal vibrations during a clothes-washing process are avoided. Therefore, normal application of the washing machine is ensured so that damage is avoided.

The invention discloses a factory building structure vibration control method of a pump station. According to the factory building structure vibration control method of the pump station, dominant natural vibration frequency of a structure system is adjusted through modifying a structure section size and increasing a counterweight, the structure system and dominant frequency of external load excitation are enabled to be staggered far, and vibration control is achieved; and main natural dominant vibration frequency of a factory building structure and pulsation dominant frequency of a machine group transient-state process are staggered through structural dynamic optimization design, and reducing or controlling structure vibration peak values is achieved. According to the factory building structure vibration control method of the pump station provided by the invention, the vibration problem of the factory building structure is regarded as a forced vibration problem under the action of external random vibration sources, and thus according to basic theories and methods of structural dynamics, a most basic principle of reducing or suppressing structure vibration is to adjust and control dynamic characteristics of the structure to enable the dominant natural vibration frequency thereof to be as far as possible from the dominant excitation vibration frequency of loads on a frequency spectrum.

The invention discloses a fully mechanized coal mining face real-time three-dimensional imaging method and system based on multiple laser radars. The imaging method comprises the steps that the pose of any laser radar in a corresponding hydraulic support coordinate system is acquired, and the laser radar is preset on the corresponding hydraulic support; acquiring original point data of a local fully mechanized coal mining face in the field of view of any laser radar at the current moment; performing local real-time imaging on the local fully mechanized coal mining face through the original point data; and by taking a hydraulic support coordinate system as a reference, converting a result of any local real-time imaging into the hydraulic support coordinate system so as to carry out global real-time imaging. According to the imaging system, laser radars are arranged on a hydraulic support, and sub-processors corresponding to the laser radars, a total processor connected with the sub-processors and software for executing the imaging method are arranged. Local real-time imaging and global real-time imaging of the fully mechanized coal mining face can be achieved, and an original mine structure does not need to be transformed.