Torque motors

Starter type Motor voltage Motor current Line or source current Motor torque Source voltage dip... 

Motor Torque, Load Torque and Selection of Motors... 

Motor torque, load torque and selection of motors 2/37... 

Since the stator current is a function of the rotor current, the motor torque is proportional to the square of the stator current. Generalizing,... 

Thus at no load, irrespective of the motor torque and the type of switching, the starting heat would remain the same. 

Figure 6.63 Motoring and generating torque curves for a 1500/1000 r.p.m. dual-speed motor (torque and current curves for generating region are drawn for only low-speed winding)...

Ki = mean load factor, i.e. the ratio of the average load torque to the motor torque which depends upon the loading on the motor during start-up. 

A ball mill requires a high starting torque (Section 2.5 and Table 2.3) to accelerate its heavy masses. In the star position, the motor torque diminishes to one third the starting torque as on DOL. The mill would take a lone time to accelerate and the... 

Locked motor torque -]y/c to + 259c of the guaranteed torque (-i- 259c may be exceeded by agreement)... 

Textile motors Crane motors Determining the size of motor Sugar centrifuge motors Motors for deep-well pumps Motors for agricultural application Surface-cooled motors Torque motors or actuator motors Vibration and noise level Service factors Motors for hazardous locations Specification of motors for Zone 0 locations Specification of motors for Zone I locations Motors for Zone 2 locations Motors for mines, collieries and quarries Intrinsically safe circuits, type Ex. f Testing and certifying authorities Additional requirements for ciritical installations Motors for thermal power station auxiliaries Selection of a special-purpose motor... 

Figure 2.8 shows a reduetion gearbox being driven by a motor that develops a torque T tn(t). It has a gear reduetion ratio of and the moments of inertia on the motor and output shafts are and /q, and the respeetive damping eoeffieients Cm and Cq. Find the differential equation relating the motor torque CmfO and the output angular position 6a t). 

Motor Torque, 651 Power Factor for Alternating Current, 652 Motor Selection, 653 Speed Changes, 654 Adjustable Speed Drives, 659, Mechanical Drive Steam Tmbines, 659 Standard Size Turbines, 661 Applications, 662 Mtyor Variables Affecting Turbine Selection and Operation,... 

PrImary-Voltage-Control-AC Motor Driver. Induction motor torque at any slip s is proportional to primary V. Rotor-power dissipation is equal to s times the air-gap power. These two relationships define the boundary of operation of an induction motor with primary voltage control of speed. As the speed is reduced (s increased) at constant torque, the air-gap power remains fixed, but the power divides between rotor circuit dissipation and mechanical shaft power. 

With this technique the motor has a wound rotor brought out to slip rings and an external resistance is connected into the rotor circuit. This resistance usually consists of a series of resistor banks, which are switched out progressively in a number of steps as the motor accelerates. The number and rating of each step is chosen so that starting current and motor torque are within requirements. 

Although not a design that guarantees positive power transmission, a satisfactorily performing friction clutch will transmit the maximum torque output of the driver to the driven shaft without slip when fully engaged. The automobile clutch is the most common example, transmitting the maximum motor torque to the wheels. 

At a maximum rate of 440 kg/h, the extruder was rate limited by motor torque and not by the quality of the extrudate. This extruder was fabricated with a gearbox and sheave ratio such that the maximum screw speed was 105 rpm. Since the process was operating at a screw speed of 45 rpm, the sheave ratio could be changed such that the maximum screw speed would be about 75 rpm. This might allow the process to operate at rates up to 700 kg/h. Changing the sheave ratio will increase the torque to the inlet side of the gearbox. Care must be taken to make sure that the additional torque does not harm the gearbox. 

A pressurized direct-drive concentric cylinder viscometer system (Figure 3-21) was used to obtain shear rate versus shear stress data on a tomato puree at several fixed temperatures between 76 and 120°C (Figure 3-22), and temperature versus apparent viscosity data at several shear rates on a 4% waxy rice (WR) starch dispersion during gelatinization over the temperature range 30 to 110°C (Figure 3-23) (Rao et al., 1998). The drive motor, torque unit, and concentric cylinder unit and temperature control vessel of a Haake RV2 viscometer system (Haake Inc.) were placed in a chamber (PRC) that could be pressurized to 0.2 MPa (two atmospheres). The temperature control vessel was insulated to minimize heat loss. A eopper-constantan (36 gage wires) thermocouple plaeed in the well of the inner eoneentric eylinder measured the temperature of the test sample. 

The motor power is also related to the motor torque (T) and speed (to) by... 

The angular momentum balance provides a relation for the required motor torque ... 

A satellite tracking antenna has an angle 6 (radians) with the horizontal axis that must change as the satellite travels across the sky. To accomplish this, a feedback controller Gc(s) is used. The controller s setpoint is the desired angle and its output is the drive motor torque on the antenna T, Wind also exerts a torque on the antenna Tp. The equation of motion of the antenna is... 

---