摘要:
The present invention is applied to a tribological pair comprising two metal pieces, a first of them having a movable contact surface which provides friction in relation to a respective contact surface of a second of said metal pieces. According to the present invention, the first metal piece has its contact surface defined by a coating formed: by a first surface layer in a material harder than that of the first metal piece; and by a second surface layer, disposed onto the first surface layer and in a material defining a coating which reduces the chemical affinity in relation to the contact surface of the second metal piece of the tribological pair, in order to provide, to said tribological pair, a lower friction coefficient in relation to the tribological pair deprived of said coating.
摘要:
The present invention refers to methods for controlling a double suction compressor for application in refrigeration systems, capable of meeting the different demands for cost, efficiency and control of temperatures by means of techniques of complexity levels and different configurations of the elements from the control loop (temperature sensors, actuators, controllers, etc.). The proposed solutions include the description of a method for controlling and adjusting the refrigeration capacities of a refrigeration system equipped with a double suction compressor, the refrigeration system comprising compartments to be refrigerated and comprising at least two evaporators (20) positioned in the compartments to be refrigerated (60,70), the double suction compressor (10) being controllable to alternate its compression capacity, the method comprising steps of (i) Continuously measuring at least a temperature coming from a temperature sensor (SET,SCT) associated with at least one of the evaporators (20) and (ii) acting in the compressor's (10) compression capacity, from the measurement of step (i).
摘要:
The present invention relates to a control system, a method and arrangement for motors and motor-compressors, designed for operation in a wide voltage range of the feed network. The control system, method and arrangement for motors and motor-compressors basically consist in associating an electronic control (10) capable of regulating the voltage supplied to a motor with windings and a magnetic core suitably dimensioned so as to fully meet the start and operation torques in the minimum voltage expected for the electric energy network, the electronic control (10) incorporating the method of limiting the effective value on the motor windings so as to keep its capability of meeting the minimum torques specified for the application, independently of the rise in the network voltage to values higher than the minimum voltage expected for the network.
摘要:
A starting system for a single-phase induction motor, comprising: a stator having a running coil (11) and a starting coil (12); a power source (F) which supplies current to said running coil (11) and said starting coil (12); a running switch (S1) and a starting switch (S2), respectively connecting the running coil (11) and the starting coil (12) to the power source (F) when in a closed condition; and a control unit (30) which is programmed to operate the running switch (S1) so as to cause a delay in the supply of the current supplied to the running coil (11) in relation to the supplied of the to the starting coil (12), during the motor start for a determined time interval which is previously defined and considered from the zero-crossing moment of the current supplied to the stator.
摘要:
A system of controlling an electric motor, a digital method of controlling an electric motor and an electric motor are described. The system of controlling an electric motor of N phases comprises a microcontroller (10), an A/C converter (30) associated to the microcontroller (30), a set of voltage meters (DN) associated to the A/D converter (30), a set of switches (SW2N) connected to an electric voltage (VBUS) and associated to the microcontroller (30), the microcontroller (30) selectively feeding, by means of at least two switches (SW2N) two phases (FN) of the motor (20) with the voltage (VBUS) during a period of time (TPOS), the movement of the motor inducing the electric voltages (EN), the set of meters (DN) measuring the signals of electric voltages (fN) and comparing these voltages with each other to determine the period of time (TPOS).One describes also the calculation of a parameter, called H(r), used to adjust the instants of commutation according to the constructive type of the motor. The parameter depends upon the rotation of the motor.One also foresees the use of a digital filtering technique, to eliminate the effects of the modulation on the control method. The filtering is characterized by the arithmetic mean of the last k samples of each average electric voltage (fN), these samples being synchronized with the period of modulation.
摘要翻译:描述了一种控制电动机的系统,控制电动机和电动机的数字方法。 控制N相电动机的系统包括微控制器(10),与微控制器(30)相关联的A / C转换器(30),一组电压计(D N N N) 连接到A / D转换器(30)的一组与电压(V SUB BUS)相连并且与微控制器(30)相关联的一组开关(SW&lt; SUB&lt; 微控制器(30)通过电动机(20)的两相(F SUB N N)的至少两个开关(SW 2NN)选择性地馈送电压(V 在一段时间(T SUB>)期间,引起电压的电动机的运动(E SUB> N SUB>),该组 测量电压信号(f N N N N)并将这些电压彼此进行比较以确定时间段(T < SUB>)。 还描述了用于根据电动机的结构类型调整换向时刻的称为H(r)的参数的计算。 参数取决于电机的旋转。 还预计使用数字滤波技术来消除调制对控制方法的影响。 滤波的特征在于每个平均电压(f N N N)的最后k个采样的算术平均值,这些采样与调制周期同步。
摘要:
A control system for hermetic cooling compressor includes a reciprocating compressor (3) and an electronic control (2) for the reciprocating compressor (3). The electronic control (2) is configured for, after commanding the turning off of the reciprocating compressor (3), detecting whether the turn velocity (23) of the turning axle (10) is below a predefined velocity level, and then applying a braking torque (36) that causes deceleration of the turning axle (10) before completing the next turn of the turning axle (10), in case the turn velocity (23) detected is below the velocity level (34).
摘要:
The present invention refers to methods for controlling a double suction compressor for application in refrigeration systems, capable of meeting the different demands for cost, efficiency and control of temperatures by means of techniques of complexity levels and different configurations of the elements from the control loop (temperature sensors, actuators, controllers, etc.). The proposed solutions include the description of a method for controlling and adjusting the refrigeration capacities of a refrigeration system equipped with a double suction compressor, the refrigeration system comprising compartments to be refrigerated and comprising at least two evaporators (20) positioned in the compartments to be refrigerated (60,70), the double suction compressor (10) being controllable to alternate its compression capacity, the method comprising steps of (i) Continuously measuring at least a temperature coming from a temperature sensor (SET,SCT) associated with at least one of the evaporators (20) and (ii) acting in the compressor's (10) compression capacity, from the measurement of step (i).
摘要:
A system and a process for energizing loads through a control unit, said loads being energized from a power network, said system comprising: connecting elements, each including a processing unit operatively connected to a respective power switch so as to lead the latter to opening and closing conditions, de-energizing and energizing a respective adjacent load that is electrically coupled to the connecting element; a pair of electrical conductors connected to a power network for energizing the loads and which are disposed so as to define an energizing means which is common to the connecting elements and to the control unit; and a signal conductor not galvanically isolated from the power network and which is common to the processing units and to the control unit, connecting them so as to allow the control unit to instruct, through the processing units and through coded electrical signals, the opening and closing of each respective power switch.
摘要:
A method for controlling and protecting electric motors, specially permanent magnet motors electronically actuated by a control system. The system includes a three-phase inverting bridge, in which the position of the rotor can be monitored by using a position detector physically attached to the axle or through the tension induced in the coils by the magnet, in order to correctly control actuation by the control system. The present invention is also directed to a system for controlling electric motors and an electric motor system. The system includes continuously reading the position detector until a minimum expected time has passed. After the minimum expected time has passed, there is continuous reading of the position detector until a maximum expected time has passed to detect if a position change of the rotor is sensed.
摘要:
An electric motor rotor with permanent magnets, the rotor including magnets (20) seated against a cylindrical lateral surface (11) of the core (10) of the rotor and a pair of annular caps (40), each cap being seated and affixed to an adjacent end face (12) of the core (10), the annular caps (40) limiting axial displacements of the magnets and defining, for both directions of circumferential displacement, stops for this displacement for each magnet (20), the confronting lateral edges (21) of a pair of consecutive magnets (20) being positioned by the annular caps (40), in order to define a previously established minimum circumferential distance.