Although the use of electronic alternatives continues to rise, mechanical components remain an important part of motion control. In fact, as electronic motion components proliferate, integration of electronic and mechanical components has become the No. 1 motion control challenge for controls engineers. That’s according to almost half of Control Design’s readers in our 2011 Market Intelligence Report on motion, drives and motors, up from just over 39% of respondents to the 2010 survey.
More than half of our respondents use primarily standard motors, and even more (64%) primarily use servo motors. A little more than a quarter (28%) primarily use stepper motors. New to our poll this year, we added high-efficiency and premium-efficiency motors to the mix. More than 41% of respondents said they primarily use high-efficiency motors, and 35% said they use premium-efficiency motors.
According to our 2010 motion survey, for linear motion applications just over a quarter of our audience favors ball screws and lead screws with slides and guides, and following closely behind (at less than 24%) are pneumatic actuators. Almost 18% use primarily direct linear motors/drives.
Significant challenges among those polled in 2011 are more precision/less drift, and faster updates/better synchronization. Although 2010 showed a slight uptick in the need for speed, those needing update rates of faster than 100 µs fell this year from 12% to 5%. The most common update rate required is 1-99 ms at almost 38%, up from about 32% in 2010. About a quarter of the respondents required updates in the microsecond range, overall about the same as last year.
More than half of respondents said position control and speed control were of highest importance for motion performance characteristics. Considered of importance but to a lesser degree was torque control.
Control the Turns
SLM and SLG rotary actuators with Class I, Div. 2 certification are suited for operating quarter-turn or multi-turn valves or shaft drive dampers. Directly coupled shaft-to-shaft, these actuators eliminate cumbersome mechanisms needed by pneumatics. To meet application requirements, the Class I, Div. 2 rotary actuators are also available with resolver feedback and handwheel options.
400 Series Profile Rail Linear Guides are available in 4 m lengths with rail sizes 5–45 mm in 5 mm increments. They include double-faced ball track bearing arrangements with standard or ball cage carriages that use the same rail design. Guides are rated to handle loads 9800–129,500 N.
Remembers Its Place
TL-Series electric cylinders for smaller, lighter-duty industrial packaging applications in 200-230 Vac systems have speeds to 1 m/sec and positioning repeatability ±0.02 mm. Non-rotating stainless-steel piston rod actuators operate without externally mounted limit or home switches, retaining position during a power loss for faster machine restarts.
OLE actuators with speeds to 22 in./sec, strokes to 18 in. standard, and thrusts to 350 lb are available in 1.5, 2 and 3 in. diameters with standard trunnion, block front, clevis, pivot and foot mounts; reverse parallel motor mounts with rear pivot or clevis; step motors; drivers; encoders; brakes; washdown rating; female rod threads; and switches.
Slimline-normal and slimline-long runner blocks replace ball rail with roller rail systems to increase the load capacity of the axis. Corrosion-resistant Resist CR version has a matt silver, hard-chrome-plated steel body. The line sizes range 25–55 in accuracy classes P and SP.
Camco RSD zero-backlash, cam-actuated drive can be used with both rotary and linear systems and is compatible with a variety of industry-standard servo motors, and offers ratios of 4:1 to 18:1 in a single stage. Output options are large flange with thru hole, 32 mm diameter shaft, external shrink disk for 30 or 40 mm shaft, and internal shrink disk for 30 mm shaft.
Bevel Geared Motor
Two-stage right-angle GKR beveled gearbox combined with synchronous or asynchronous motors have a lightweight aluminum case and rated output torques to 450 Nm. Options include hollow shaft with keyway or shrink disc, solid shaft with keyway, foot or flange mounting, and torque plate with rubber buffer.
RESF37 stainless steel helical gear reducer and KESA37 stainless steel helical bevel gear reducer are shaft-mounted gear units with TorqLoc compact keyless hollow shaft mounting system that combines interchangeable bronze bushings and a stainless steel clamping ring for mounting onto various sized solid shafts. They are available with NEMA C-face motor adapters, IEC adapters or as gearmotors. Other options include seals to provide IP69K protection and food-grade oil.
ACT linear motor actuator alternative to ball screws and belt drives has travel ranges 100 mm to 1.5 m, acceleration capability to 5 g, velocity to 5 m/s, maximum continuous force output to 270.7 N with a maintenance-free, direct-drive, zero-cogging motor and noncontact optical linear encoder.
Geared to Go
Precision planetary gears for synchronous and stepper motors are single-stage for gear ratios i=3, 4, 5, 8 and 10 and have ≤8-15 arcmin backlash. The gears are also offered in two-stage or three-stage designs. The premium series provides backlash ≤1 arcmin as an option paired with high-output torques. The planetary gears are delivered fully mounted on 8LSA, 8LVA, 8JSA and 80MP series motors.
B&R Industrial Automation
Catalog of adjustable-speed drives, right-angle gear drives and linear actuators contains new product models, technical application data, drawings and photos. Adjustable-speed drives provide infinitely adjustable speed control with Micro Dial for inputs from ¼–1½ hp applications with output torque ratings 12-200 in.-lb. They accept input speeds 0-2,000 rpm and are available with optional gearheads, motors and c-flange adapters.
Protect Your Lower Backlash
RLSS rod locks, Generation 2, with optional embedded engagement sensor deliver holding forces to 5,000 lb with low backlash. A clamping collar applies a 360° holding force around the cylinder rod. Models are CE-marked and RoHS-compliant.
Variable Stroke Actuator
ERD electric rod-style actuator has ball screws and two stainless steel options. It provides thrusts to 200 lb-ft, speeds to 40 in./s, and stroke lengths to 12 in.
Line of pneumatic Minimatic cylinders in stainless steel, brass, metric, corrosion-resistant, and compact series are offered in 12 bore sizes with strokes to 40 in. Options include 304 stainless steel tubes for low breakaway, anodized heads for extra corrosion protection, sintered bronze bushings, U-cup piston seals, and accessories.
Clippard Instrument Laboratory
To Measurement and Beyond
Infinity 1 roller screw actuator has an IP rating of IP64+ and possible IP68 (motor-dependent) via a hermetically sealed case. The enclosed integrated position transducer offers absolute position measurement in analog and SSI output. The integrated load and torque sensor offers absolute load measurement in analog mV output with no translating wires.
Series FGXS twin bore, precision table slides have a rail bearing system for smooth operation. Magnetic pistons and sensor mounting slots are standard. Optional sensors feature surge protection, polarity protection, LED indicator, and fast switching speeds. Options include adjustable stroke and shock absorbers, bores 8–25 mm, and strokes to 150 mm.
R08 Planetary Gearhead delivers continuous torque of 0.05 Nm, available in 4-256 ratios that can be further extended to ratios of 4,096. The gearhead can be coupled with brush dc, brushless and stepper motors in their respective frame sizes. It can be customized to meet specific application requirements.
Mechanical ramp-down attachment for Amacoil/Uhing linear drives needs only a slowdown arm added to the reversal mechanism and an extra end stop bolt on the assembly supports. Production and maintenance personnel need not learn any special procedures or skills. Example applications include moving overhung or cantilevered payloads in linear motion systems with minimal whipping or jolting of the payload.
Ultra Kleen right-angle, worm gear reducers are available in quill and three-piece coupled input and with solid or hollow output. Made of stainless steel for washdown protection, the units are available in ratios of 17, 21, 23, 26 and 30 with center distances 1.75-3 in., and a factory-filled H1 food-grade lubricant.
MDrive linear actuators with integrated step motor and driver technology come in three motor sizes and non-captive and external shaft styles, with options including programmable controller and motion control technology. These products have an input voltage range of 12-75 Vdc, nominal load limits of up to 200 lb and full (256x200) microstepping with an operating temperature range of –40 to 85 °C.
Intelligent Motion Systems
Nitra pneumatic line of stainless steel, round body, non-repairable cylinders feature type 304 stainless steel bodies with double rolled-in construction with high-strength aluminum alloy porting ends. Single- and double-acting models are available with nose, pivot and double-end mounting options. Some models are available with magnetic pistons for position indication. Bore sizes range 7/16–2 in. Depending on bore size, available stroke lengths range ½–18 in.
SBK ball screw has a recirculation structure where balls are picked up in the tangential direction and the lead-angle direction by end caps. It has Caged Technology with a synthetic resin cage and patented curvature that cradles each ball and separates it from the next one. SBK is available with screw shaft outer diameters ranging 15–32 mm and nut diameters ranging 38–58 mm.
PDP alternative to ball screws is made of two ground WMH pinions connected through a preload system to reduce rack-and-pinion mesh backlash. When mounted at the output flange of SRP, a high-tech planetary gearhead, PDP offers four different modules with straight or helical teeth, eight reduction ratios, angle-drive versions, two-output pinion diameters for each size, and an input interface in-line flange or with a 90° angle.