Floor platforms designed to isolate low-frequency vibrations from SEMs and TEMs
Give us your low frequency vibration isolation challenge
The FP-1 consists of a large platform, two or three Minus K® SM-1 negative-stiffness vibration isolators, outriggers which connect the platform to the isolators, isolator floor and jack screw plates which help to spread the load on the floor and ballast weights.
The FP-1 platform is a heavy steel plate which typically weighs nearly as much as the microscope itself. One reason for this design is to lower the overall system center of gravity to the level of the isolator tilt mechanism, so as to avoid horizontal-tilt coupling, which occurs when horizontal vibrations cause both a horizontal and tilting response of the column. With the system CG at the level of the isolator tilt mechanism, the vibrations are decoupled and better isolation control is achieved. Another reason for the massive platform is that the large total mass of the system helps to diminish any effects from stiff cables and hoses connected to the microscope.
For SEMs and some TEMs only the column console is isolated. In some cases the column, display and other components are isolated on the platform.
The system can achieve natural frequencies of 0.5 Hz or less, vertical and horizontal, with all external line, hoses and cables disconnected from the isolated payload and the internal isolators locked out. (with most microscopes the external lines, hoses and cables have a relatively small effect on the isolation system performance)
Customers that prefer to make the platform themselves can purchase the design, the SM-1 Minus K negative-stiffness vibration isolators and build the platform locally to save fabrication and shipping costs.
Hitachi S-4800 SEM on a three-isolator floor platform
WITHOUT MINUS K VIBRATION ISOLATION
WITH MINUS K VIBRATION ISOLATION
LEO 1550 SEM on a two-isolator floor platform
This is a horizontal only FP-1 for a JEOL JEM 1400 TEM on a 5th floor.
JEOL JEM-1400 TEM out of spec before Minus K’s FP-1
JEOL JEM-1400 TEM within spec with Minus K’s FP-1