Tiny Pump Simplifies Vacuum Device Design

Designers of pick-and-place, robotic handling, and packaging machinery may now have a smaller, lighter alternative to the air- and motor-driven pumps they often use in order to generate a vacuum.

A tiny new vacuum unit developed by engineers at Hingham, MA-based Piab Vacuum Products reportedly is about half the size and weight of comparable air-driven pumps, and less than one-tenth the size of motor-driven versions. The new multi-stage ejector vacuum pump, known as the Piab 2010 (http://rbi.ims.ca/3846-527), is being marketed for applications in electronic pick-and-place systems, circuit-board testing, and printing presses.

It can also serve in robotic systems for handling of automotive windshields and hoods, and in packaging machinery for opening and closing of corrugated boxes. Because it doesn't require lubrication, the system could additionally be employed in semiconductor clean rooms and food processing, where use of oil is not permitted.

The company says that the new multi-ejector pump measures a mere 0.39 inches wide, 1.08 inches high, and 1.3 inches long. It weighs as little as 0.54 ounces. In contrast, its nearest competitors are said to measure 1 x 2 x 3 inches and weigh no less than 1.2 ounces.

Moreover, the company's engineers say that the P2010 can generate a vacuum pressure of 24.9 inHg with a feed pressure of 26 psi. By comparison, most comparably-rated systems require feed pressures ranging from 59-87 psi. "Any vacuum unit can generate as much vacuum as this pump, but to do it at this low input pressure and this small size is unusual," notes Mike Tuohey, marketing communications manager for Piab Vacuum Products.

The new unit accomplishes that performance with a patented technology it calls "coax." The coax technique involves the use of a cartridge containing rubber diaphragms, called flap valves, along the top. During operation, air is introduced into the cartridge from one side and as it subsequently passes through at high speed, it causes the flap valves to close down from the outside. The opening and closing of the valves creates a vacuum, engineers say. "Nature abhors a vacuum," Tuohey says. "It wants to eliminate the vacuum and its does that by sucking in air to replace what's no longer there."

Tuohey notes that the coax approach is responsible for the unit's small size. And that small size, he says, enables it to be employed in applications where vacuum pumps might not have been used previously.

In robotics, for example, motor-driven vacuum pumps have traditionally been too large to be placed at the end of a robot arm. Standing more than a foot high and sometimes weighing in at 10 lbs, such vacuum pumps have often been located remotely.

"Some of the motor-driven pumps have been so large and so noisy that they needed to be placed in a different room, away from the application," Tuohey says. "The problem is, you then have to evacuate those long vacuum lines whenever you start it up again."

In contrast, Tuohey highlights that the 2010 can be placed directly on the robot arm, making for easier evacuation and faster cycling. "This is half the size and half the weight of the smallest mini-ejector pumps," he says. "So you're always going to be able to put it close to your source of vacuum."