Finely tuned precision - Miniature bellows couplings in micromanipulators
A micromanipulator facilitates extremely precise operation with the assistance of additional instruments. This allows the coarse movement of a human hand to be transformed into extremely fine motion when working the finest microcapillaries, needles, and electrodes. This motion can typically be controlled mechanically, hydraulically, or electronically in all three dimensions.
These devices are very helpful in microsurgery, where operations can be conducted on living tissue or cells under a microscope with high optical resolution. Cell manipulation is the starting point of many time-lapse and multidimensional experiments. In reproductive medicine, the micro-injection of DNA, stem cells, or spermatozoon into egg cells is used to generate transgenic organisms and is used extensively in artificial fertilisation (IVF). With CRISPR/Cas9 technology, cell manipulation can be used to produce transgenic animals. Micromanipulators are also used in the micro-electronics industry. Here they can serve in integrated circuit design to position measurement electrodes precisely to aid with electrophysiology.
Maximum precision with miniature bellows couplings
Advancements in these precision industries have created the need for innovation and creativity. Christopher Monka, R+W Antriebselemente Sales, explains, "The trend for miniaturisation in sectors like laboratory medical technology, precision mechanics apparatus construction or micro-dosage pumps, endows the miniature bellows coupling with a decisive role in these growth markets." It is a great solution for torque transmission as low as 0.05Nm and for bore diameters going down to 1 millimeter.
The bellows serves not only as the central connection system between the hubs, but also allows for misalignment compensation in miniature bellows couplings. Christopher Monka explains, "The dimensions of the metal bellows depend on application requirements, necessary torque transmission, and what levels of misalignment compensation are needed." The miniature bellows coupling must have very high torsional rigidity to keep restoring forces as low as possible while compensation for misalignments. This becomes very important in drive train applications where operators need to maximize machine performance, while protecting downstream components from excessive wear. The R+W MK series manages both of these tasks effortlessly.
Case: Miniature bellows couplings in neuroscience
R+W Antriebselemente has been supplying a miniature bellows coupling solution to a leading manufacturer of research equipment for the past 30 years. This customer has been developing manipulators for many decades to be used in positioning systems for electrophysiology, injection, and bath chambers. Their so-called “neuropixel probes” are the newest addition to the product line. This equipment provides the ability to records the activity of hundreds of neurons from many different brain regions simultaneously in neuroscientific research. “The miniature bellows coupling creates a direct connection to a very finely threaded spindle and contributes to overall machine precision with its high torsional stiffness and backlash free design.”
Individually adapted thanks to flexible product range
The metal bellows coupling is suitable for a variety of applications and comes with a multitude of different connection options. "It is available with radial clamping screws, slit and divided clamping hubs, as cone clamping set or as model with expanding shaft for hollow shaft connections. For even easier installation, we can offer a pluggable, still backlash-free, version in which a fibre glass reinforced plastic conical plugging segment ensures precise torque transmission and provides electrical and thermal insulation. The pluggable designs are distinguished by a fast, hassle-free mounting connection. The end users save a lot of money by optimising their set-up times, because the complete coupling does not have to be disassembled," summed up Christopher Monka. Standard designs are readily available for most applications, but special materials and solutions can be applied for unique applications such as couplings inside of a vacuum or clean room.