Advances in Servo Motors

Refinements in performance, feedback solutions and more compact physical sizes are the overriding trends in motors. Among motion control product categories, industrial motors have the longest history and radical improvements are harder to come by. But manufacturers still are continuing to make incremental performance improvements from the motor shaft, to more feedback options and more efficient operation.

Motor products are already highly refined but the fundamental set of goals remains largely the same for new designs. Suppliers are looking to provide higher power densities, especially more power from the same package or the same amount of power from smaller packages. The highlighted items below show that more compact motor design is a main focus, along with feedback solutions. Feedback is an area where recent gains have been made, both in terms of technology and also more cost-effective solutions. Suppliers say lower cost of feedback options is helping to reduce the cost of servo motors and propel usage of servos in applications.

SYNCHRONOUS SERVOS OFFER PRECISE, DYNAMIC CONTROL

Dynamic performance, precision, adaptability and long service life are the key advantages of a new line of synchronous servomotors from SEW-EURODRIVE. The DS/CM line of servomotors provides a solution for highly dynamic applications like material handling, packaging and crane and hoist control where speed, precise movement and a high degree of concentric properties are required.

The new servomotors cover a wide range of standstill torques from 1 to 68 Nm, with peak performance ratings of up to 238 Nm. High overload capacity provides solutions for almost every power requirement. A durable housing with built-in convection cooling assures reliable performance, extremely quiet operation and exceptional service life.

The new servomotors are available with 24V holding brakes for the DS series or powerful servo brakes for the CM series. The high torque of the optional working brake for the CM series provides an optimum solution for hoist applications.

NEW 1FT7 SYNCHRONOUS SERVOMOTOR SERIES

The new 1FT7 series of synchronous servomotors from Siemens offers increased performance and user productivity. The motors are up to 30 percent smaller than the 1FT6 series and offer increased torque and a robust encoder attachment with convenient mounting options.

Siemens says this is the first servomotor with an encoder that can be replaced in the field without adjustment. Designed to withstand vibrations, the encoder operates without oscillations and integrates with both SIMODRIVE and SINAMICS drives.

Having been constructed with the flange on the drive end, the flat surface on the top provides expanded mounting options. A medium inertia motor designed for general machine tool applications, the motor has a higher overload at 4 x MO (self-cooled) up to frame size 100.

In addition to self-cooling, the motors can be cooled through forced ventilation or water cooling through “cool jets” to lower the temperature of the motor. The motors offer IP64/IP65/IP67 protection.

COMPACT, HIGH-TORQUE SERVO MOTORS

The DSC 45-100 series of high-torque servo motors from Baumüller are up to 30 percent more compact than conventional servo motors and provide a solution that is torque motor servo-ready. The motors focus on improved performance by increasing torque densities and reducing overall volume.

Even with torque increases, typical speed ranges are up to 4,000 rpm. The DSC 45-100 features a smooth housing surface to help prevent contamination build up. The motors are easy to mount and offer a high environmental protection classification.

These permanent magnet synchronous servo motors offer smooth running characteristics, high overload capability and almost no cogging torque. The smooth housing surface is easy to keep clean and provides a uniform housing design. Main and encoder connections are made via rotatable standard connectors. Motors are available with IP65 type protection and are totally enclosed non-ventilated. All types are available with optional brakes.

145 OZ-INch (1 NM) NEMA 23 FRAME SERVO MOTOR

QuickSilver Controls expands its current line of servo motors with the QCI-A23K-3. This NEMA 23 frame motor generates 145 oz-inch (1.0 Nm) continuous torque, 165 oz-inch (1.1 Nm) peak torque and 58W peak mechanical power. The 23K-3 comes standard with an 8,000 counts per revolution encoder and is available in both IP50 and IP65 (washdown) packages.

Combined with the company's servo controller/drivers, the motor creates a high-torque servo control system for speeds up to 2,000 rpm. With an ability to handle inertial mismatches of 100:1, the motor is ideal for driving large flywheel loads without additional gearing. The motor requires only a single cable for both encoder and motor signals.

The 23K-3 lists at $240 and has a system cost including controller, cable and motor starting at $795 (OEM 500 piece $511). It is a solution for semiconductor, packaging, medical and food processing applications.

BALDOR ANNOUNCES NEW SMALLER SERVOMOTOR

A new family of BSM40R and BSM60R motors from Baldor provides a compact, lightweight servomotor available in either metric or NEMA (stepping motor) mounting configurations.

The new motors enable designers to use the fundamental benefits of brushless technology, less maintenance, quieter operation and faster accelerations, in smaller packages. Typical applications include pharmaceuticals, electronic assembly, packaging, automation equipment, labeling and stepper motor upgrade packages. The motors are designed to operate with the company's MicroFlex compact brushless ac servo drives.

The BSM 40/60 R-series of brushless servomotors provide 50 to 400W output with models available in 1.5 and 2.3 inch (40 and 60 mm) packages. Continuous stall torques ratings range 1.4 to 11 lb-inch (0.16 to 1.2 Nm), with peak torques of three times.

Models available from stock include a 2,000 pulse per revolution encoder. Other motors are available with custom features include a resolver or 24V dc brake options.

PLANETARY GEAR TRAIN PANCAKE MOTOR

A new low-cost planetary gear train pancake motor from Haydon Switch & Instrument delivers exceptional performance in a very thin package. Just 18.5 mm thick and 80 mm in diameter, the motor is built using a gear train built inside the rotor. The thin profile is a result of this unique design.

The motor is available with a 3.75 degree step angle, 4:1 gear ratio and provides up to 120 oz-inch of torque (85 Ncm). It is ideal for applications with limited space, requiring accurate positioning and high torque.

Haydon custom designs and manufacturers electric motors for medical equipment, instrumentation, industrial equipment, machinery automation, HVAC, telecommunications, semiconductor, office equipment and many other custom applications. The unique designs provide precise, reliable motors with unmatched performance-to-size ratios. Motors are simple and versatile, making them well-suited for customization and manufacturing.