Piezoelectric Force Sensor Width Reduction via Axial Preload

The patent repositions the preload screws from a width-direction arrangement to a height-direction arrangement along the central axis. This dimensional change allows the screws to apply precompression force vertically through the piezoelectric sensor parts without increasing the apparatus width, thereby resolving the contradiction between height reduction and width minimization.

The patent employs asymmetric placement of the two preload screws relative to the central axis, positioning them at different radial distances. This asymmetric configuration optimizes the application of precompression force while minimizing the required width, as the screws are not symmetrically distributed but rather positioned to efficiently compress the sensor parts along the height direction.

The patent arranges multiple piezoelectric sensor parts in the height direction along the central axis rather than distributing them in the width direction. This vertical stacking configuration enables multi-directional force detection through the stacked sensors while maintaining a compact width, as the detection capability is achieved through axial arrangement而非 lateral expansion.

The patent implements a nested configuration where multiple piezoelectric sensor parts are stacked concentrically around the central axis, with each sensor part positioned at different radial distances. This nesting arrangement allows multiple sensors to occupy overlapping projection areas when viewed from the width direction, thereby achieving multi-directional force detection without proportionally increasing the apparatus width.