Speed valve completes full-force regenerative hydraulic circuit

Aug. 9, 2001
Putting a regenerative hydraulic circuit on a double-acting piston reroutes the flow exiting the rod side of the cylinder from the reservoir to the piston side of the cylinder.

Putting a regenerative hydraulic circuit on a double-acting piston reroutes the flow exiting the rod side of the cylinder from the reservoir to the piston side of the cylinder. It merges with pump flow and increases the piston speed, but not the force it exerts. That's because both sides of the piston are exposed to system pressure, so the maximum force the piston exerts depends on the differential area between the cylinder's rod and piston sides.

Engineers at Sherex Industries Ltd., Lancaster, N.Y., have overcome the problem of limited force by adding a switch into the circuit of its Iversen automatic speed valves. It lets the full force of the cylinder be applied once a certain pressure level is reached, and increases piston speed during portions of the stroke in which little or no work is being done. When the valve closes, return flow goes to the reservoir and the cylinder applies full force. The valve can double the speed of double-acting cylinders.

In the past, these types of hydraulic circuits were only available by custom order. Iversen valves, however, are mass manufactured as individual, compact, self-contained components. They handle pressures up to 5,000 psi and flow rates to 11 gpm. Future models will handle flows of up to 79 gpm. The valves retrofit into older equipment using in-line mounting, and no external controls are required.

Speed valves increase cylinder speeds, which can reduce cycle times on injection-molding machines, hydraulic presses, and die-casting equipment. In the example graphed, the 80/50 mm cylinder has a 800-mm stroke and pump output is 20 liter/min.

Sponsored Recommendations

Altech's Liquid Tight Strain Relifs Catalog

March 13, 2024
With experienced Product Engineers and Customer Service personnel, Altech provides solutions to your most pressing application challenges. All with one thought in mind - to ensure...

Industrial Straight-Through Cable Gland

March 13, 2024
Learn more about Altech's cable glands and all they have to offer for your needs!

Smooth Sorting with SEW-EURODRIVE!

Feb. 22, 2024
Sorting systems are essential when it comes to warehouse automation, material handling, and distribution. SEW-EURODRIVE’s automated sorting solutions increase capacity, reliability...

Setting the Agricultural Industry in Motion

Feb. 22, 2024
Agricultural products go through specialized processes of harvesting, storing, conveying, cleaning, drying, sorting, and handling to ensure that seasonal products reach the processing...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!