Magic Knob™

Until now, the mainstream of devices integrated for vehicle air conditioning and volume controls are mechanical switches and rotary knobs that provide mechanical feel in order to provide the certainty of operation. In recent years, differentiation by interior design is becoming more popular, and an increasing number of vehicles are adopting flat capacitive touch switches for their interiors for seamless and high design.

As various operation devices are being studied to achieve both “reliable operability” and “high design“, the need to combine an electrostatic touch switch and a rotary knob has emerged.

Furthermore, in automotive displays such as car navigation systems, there are need to place mechanical knobs directly on the display for space restrictions due to the increase in screen / display sizes.

Expecting adoption of a capacitive knob that can operate on a capacitive touch display will provide both operability and design.

For capacitive knobs, “rotating method” is commonly used in which the electrodes on the bottom  (so-called pseudo fingers) rotate as the knob rotates. This method can be used on a touch sensor with a standard pattern, but may cause problems such as kob becomes large in order to secure the adhesive area to rotate electrode on the bottom. In addition, hands are normally used as the GND which became constraints not be able to operate with gloves on.

Our capacitive knob named “Magic Knob™” solves the problem of adhesive area by combining a dedicated pattern on the touch sensor and electrodes fixed on the bottom, enabling the knob to have a smaller diameter (the smallest in the industry *according to our research). In addition, this method does not use the operator's hand as GND, which enable operations with gloves on become possible.

Magic Knob™ provides a new interface for air conditioning and acoustic control panels, which requires small diameter and simple operation.