The "Micro Tweezers"
The stainless steel "Micro Gripper"
A versatile "Micro Gripper" head with a very fine machined "tweezer" tip. Depending upon the purpose, the tips can be lapped to square shape, or it may also be etched extremely thin. This process can be controlled accurately, so that it will surpass any mechanical finishing. The tip dimensions are variable through a large range, from tenths of millimeters down to tip radii of just a few microns.
The main advantages are simple handling and robust design. Small defects at the very tip are fairly easy to repair.
It is also possible to glue a tiny lithographed structure into the tweezer jaws. The small sub-structure opens and closes by its own spring action and the pressing force of the "Micro Gripper": this opens many possibilities to work in the next magnitue of specimen sizes down.
|Pic.2: After fine lapping of the inside surfaces, the tips are closed and cut to equal lengths at the front end. Finally, they will be cut to triangular tip shape.||Pic.3: The insides remain parallel, even after etching. Depending upon the chemical attack, the tips can be shaped sturdy or made as very slender tapers.|
Working with the "Micro Gripper"
The clamping approach was chosen to be from one side, as opposed to analogy to the "movement of thumb and forefinger": a movement of one jaw only is much easier and safer to do. The gripper shown here is usually turned 90 degrees to one side. One jaw gently touches the specimen, the other closes in until it grabs firmly, without unwanted shifting action.