An existing solenoid customer asked MSA to develop an electromagnet which would fit into a unique footprint and could provide superior performance when compared to their current solution. MSA gladly accepted this new challenge because it involved a mechanical form factor we had not previously magnetically simulated, and because it was not similar to any electromagnet we had ever produced.
Stabilizing/Holding Device—a custom Electromagnet was needed to secure the X-Ray head on medical imaging equipment and hold the patient bed in place during the imaging process. The goal was to prevent harm to machine operators and patients.
- 1) Unique Shape—conform to an existing rectangular package shape and size
- 2) Improve Performance—provide greater holding force and higher shear force than the current product
Utilize MSA’s proprietary magnetic simulation software to design a custom, rectangular Electromagnet that achieved increased shear and holding forces.
Develop and implement completely new manufacturing and testing techniques, to ensure compliance with the new performance criteria, and to meet an aggressive price target.
Key design features include:
- New Bobbin and Injection-molding Tooling—to facilitate encapsulation of the coil
- One-piece Body—to help achieve the increased hold and shear forces
- Custom Winding Arbors—to enable cost-effective winding of the rectangular coil
MSA designed, tooled and brought this product to market within four months, achieved the desired increase in both shear force and static-hold force, and met the aggressive target price.
Several years after the initial design effort involving the rectangular Electromagnet, new government regulations in the industry required that all electromagnet-holding devices must continue to provide sufficient hold force in the event of a power failure. The goal of this new regulation was to protect machine operators and patients from harm if the system totally loses power.
MSA responded with a new design that embeds a Permanent Magnet into both the cylindrical and the rectangular-shaped Electromagnets that MSA manufactures. This approach achieved the desired fail-safe holding and shear forces, and also provided an additional energy-saving benefit.
The Permanent-magnet/Electromagnet design requires that only a short pulse of electrical energy be applied to the device’s coil to affect the pull-in, or the release function.
To attract and then “capture” the desired object (i.e. the X-Ray head, or patient bed), the polarity of the actuation pulse must be in sync with the Permanent Magnet. Once contact is made, the Permanent Magnet securely holds the object in place. To release the object, an even shorter electrical pulse of opposite polarity to the Permanent Magnet, is all that is required to nullify the magnet’s hold and release the object. In either the pulled-in or the released state, the Permanent Magnet/Electromagnet requires “zero” continuous energy to remain in that state.
Zero-energy consumption, Permanent Magnet/Electromagnets have also found use in other markets, such as automotive, food-preparation equipment and building security.