Streamlining designs, more on efficiency
Links in robotic arms are typically special, often complicated designs that tend to vary from one manufacturer to the next. igus (igus.com) now offers robot developers and laboratories a simple, lightweight, maintenance and corrosion-free series of connector joints for humanoid systems or common light assembly and handling applications.
The simple plastic links permit 2° of freedom, but the links can be combined to provide wide-ranging movements and flexibility. The inspiration, according to igus officials, was bionics, mimicking human muscles bones and tendons.
High-tensile synthetic fibers transmit forces as pure tensile loads. The wires have low thermal expansion, are chemical resistant, lubrication-free, and exhibit almost no wear. The modular units snap together and function similar to a ball joint. The power source for the robot arms is at the base. Keeping most of the mass away from the moving parts permits high-speed movements. The soon-to-be-released modular kit includes molded links, arms in several lengths and styles, wire ropes, connections to drive and control units, and various end effectors such as grippers and vacuum cups.
Automatic code generation
B&R (br-automation.com) is releasing an automatic code-generation tool called Automation Studio Target for Simulink. The product works B&R’s Automation Studio development software — as well as Matlab products from The MathWorks (mathworks.com). According to B&R officials, the package significantly speeds system design, development of simulation models, and testing scenarios. And with the push of one button, designers can convert the design model to control code in a few seconds. With conventional programming, the process can takes weeks. Thus, it reduces development costs. Another benefit is that it is based on proven MathWorks, so there is a low risk of coding errors. For the OEM, it improves the quality of the control structure, for instance machine sequences, or PID or adaptive controllers.
Low-friction seals
Parker Hannifin’s Seal Group (parker.com) has developed HL friction-optimized seals that reduce energy consumption in hydraulic cylinders. High friction also causes wear that leads to premature failure and downtime. The novel HL design uses three progressive sealing lips. At low pressures, only one lip engages the cylinder rod. This minimizes break-away friction, and the small contact area generates little friction and heat, permitting high-speed movements. Higher pressures force the other sealing lips into contact with the rod. But because of the higher linear forces, dynamic friction increases only slightly as the contact area enlarges.
The HL is made of a low-friction polyurethane. It can be used alone with a wiper, or as a secondary seal behind a primary or buffer seal. Operating pressure is to 250 bar.
High-efficiency coolers
Rittal (rittal.com) has expanded its range of Cool Efficiency cooling units for electronics enclosures and control cabinets with products rated up to 2-kW output. They reportedly use up to 45% less energy than more-conventional units of the same size. Savings come from the latest refrigeration compressors and fans, and through an improved layout of heat-exchanger components and greater refrigerant capacity. External rotor motors with electronic commutation are dynamically balanced and Hall-effect sensors track rotor position. Precision bearings give long service life and low noise. The new products also have proprietary nanocoatings that shed dirt and improve condenser performance.
Oil bath for electric cylinders
SEW Eurodrive (seweurodrive.com) has transferred its proven gearmotor-lubrication system to linear drives. This reportedly offers benefits such as consistent warm-up, higher efficiency, and no maintenance. Electric cylinders are normally lubricated with grease that eventually needs relubrication. SEW’s CMS63S electric cylinder consist of a servomotor and a linear drive that connects directly to the motor without adapters and couplings. The linear drive sits in an oil bath contained by a redundant sealing system.
The bath reportedly improves the service life of the spindle nut, bearings, and guides. There is less friction and heat, and the lubricant also helps cool the motor. In addition, the device has smoother start-up with less stick-slip.
Compact hydraulic power
Hawe Hydraulics (hawehydraulics.com) announced its smallest hydraulic power pack yet. It measures only about 12 × 4 × 4 in. and weighs about 18 lb. But it can generate pressures up to 500 bar (7,250 psi), depending on the valve configuration. Because of its size, it easily installs in small spaces and comes available with a radial piston pump, thus ensuring long service life. The power pack is designed for use in hydraulic equipment with low oil-volume requirements on mobile applications such as construction sites and other locations where energy is supplied by dc-power sources. The power packs are also for applications where operating modes have short activation times, including riveting, crimping, embossing, and releasing of winch brakes. Operable oil volume is approximately 0.7 liters.