WOB-L piston vacuum pumps use a direct-drive mechanism to generate oil-free vacuum. They’re compact, low-maintenance, and ideal for applications where clean gas is essential—like medical devices, lab equipment, and packaging systems.
The operation of piston vacuum pumps revolves around a set of key components: an electric motor, a crankshaft, a connecting rod, and a piston enclosed within a cylinder. This mechanism functions based on the principle of positive displacement. The pump's motor imparts rotational energy to the crankshaft, initiating its rotation. Subsequently, the connecting rod converts this rotary motion into the reciprocal motion of the piston.
Within the cylinder, as the piston moves alternately up and down, a vacuum is created during its downward stroke. This action prompts the medium to be drawn into the cylinder chamber via an open inlet valve. Depending on the design, single or multiple cylinders may be linked to the motor. In the latter configuration, the pump's capability is amplified, whether in terms of flow (in a parallel setup) or vacuum (in a two-stage configuration).
A distinctive feature of WOB-L® vacuum pumps is the direct connection between the piston and the rod. Unlike conventional designs, there is no intervening wrist pin; the two components form a single unit. This direct coupling results in a characteristic wobbling motion of the piston. Guided within a flanged polymer cup, the piston moves within the cylinder bore, creating a seal against the cylinder wall.
As the piston moves, air pressure expands the cup against the cylinder wall, compensating for its wobbling action. This innovative design ensures exceptional vacuum capabilities relative to the pump's compact size and lightweight construction. Additionally, it maintains consistent moderate-to-high flows, contributing to sustained performance throughout the product's lifespan.