Four-way valve offers less leakage, lower cost
Conventional four-way solenoid valves are often complex and expensive. Some manufacturers make their four-ways by employing 2 three-way valves; others use a power-consuming shear seal design. A new design, however, offers an alternative. Using an internal poppet valve, it offers higher pressures, uses less power, dramatically reduces leakage, and costs about half as much as conventional valves. Operating at 6,000 psi, it reportedly reduces leakage to about five drops per minute while consuming little power. "It needs only 18W," notes the valve's designer, Thomas Hotchkiss, president of Interface Devices Inc. "That's a lot less than other valves are using."
Interface Devices: Product Code 4797
Computer selects pump pressure
In level flight, an aircraft's hydraulic system needs more pressure than it
does during landing or take-off. Using the Vickers PV3-400-5 engine-driven hydraulic pump, an aircraft can now switch back and forth between those higher- and lower-pressure requirements. The system, already in use on military aircraft, enables the aircraft's computer to quickly change pump pressure from 3,000 to 5,000 psi, or vice versa. The unit's 78 gpm, 4,480 rpm variable displacement pressure-compensated inline design provides hydraulic power for flight control and utility systems at either pressure setting.
Vickers Inc.: Product Code 4801
Quick connector eases hydraulic hookup
Users of agricultural machinery and construction equipment know that hydraulic lines can be a pain to hook up. Using a new quick connector assembly, however, the connection process is no longer so painful. Sherex Industries' MACH connectors enable users to simultaneously connect up to seven hydraulic lines and six electrical lines. As a result, the unit eliminates connection errors while speeding assembly. "With this, you can connect or disconnect all the lines at once," notes Sherex Vice President Henry Bourg. "And you always get it right, because it can only be connected one way."
Sherex: Product Code 4800
Solenoid valve simplifies inventory
Most users of solenoid valves stock electrical coils on their shelves the better to meet the needs of every potential hydraulic circuit. Now, however, valve users won't need to stock a variety of high power and low power coils. Thanks to a new series of threaded cartridge valves from Parker Hannifin, one or two coils will meet the needs of every application. Known as the DSL Unisol series, the new valves work with replaceable, one-piece encapsulated coils. They are available in two-way poppet-type, and two-, three-, and four-way spool-type configurations. "The big advantage is the coil is nearly universal," notes Don Caputo, marketing manager for Parker Hannifin's Hydraulic Valve Div. "And that gives the customer greater flexibility."
Parker Hannifin: Product Code 4798
Motor-pump saves space
When engineers from Mannesmann Rexroth set out to make a more compact motor-pump combination, they turned to Arkansas-based Baldor Electric. The result: A unit that eliminates conventional couplings and bell housings, thus shaving about seven to 10 inches of length from the standard motor-pump combination. Known as the Close-Coupled Motor Pump Group, it not only cuts the size, but reduces labor and component costs as well. Mannesmann Rexroth engineers expect it to appeal to customers who face serious space constraints. "Bell housings can take up critical space," notes Mannesmann Rexroth Project Engineer Rob Unger. "But with this product, you never have to worry about that again."
Mannesmann Rexroth: Product Code 4799
Integrated brake/motor cuts size & cost
A new integrated brake/motor technology offers a solution to the size, cost, and reliability issues associated with braking systems for rotary actuators. Engineers from Parker Hannifin, who designed the unit, enclosed the front-mounted brake within the motor housing, thus making it more compact. By doing so, they also protected it from external contaminants. What's more, front-mounting enabled them to keep the brake operating safely in the event of a motor failure. The system provides up to 13,000 lb of holding capability. Release pressure is under 500 psi.
Parker Hannifin: Product Code 4802
'Real feel' mobile valves
More than ever, manufacturers of construction and agricultural equipment try to provide features that will reduce operator fatigue. CMX load sensing sectional control valves help meet that need by providing "real feel" and precise functional control. The CMX Control Valve also offers a unique separation of the meter-in and meter-out elements and a choice of hydraulic or electrohydraulic operation. As a result, it gives designers a greater degree of flexibility in meeting custom application requirements. Individual meter-in and meter-out elements reduce prototype development cycles and reportedly provide quick and easy customization for specific actuator needs. Result: system tuning can be completed in a matter of days, rather than weeks, as is commonly the case with spool-type valves.
Vickers Inc.: Product Code 4801