A mechanical vibrator for a timepiece in which a ceramic supporting substrate is rigidly secured to an inner wall of an evacuated housing. The supporting substrate is formed at its one surface with a pair of conducting metal layers serving as leads and at its other surface with a conducting metal layer over a substantially large area. A piezoelectric vibrating element having exciting electrodes is placed on the ceramic supporting substrate and rigidly connected thereto such that the electrodes of the piezoelectric vibrating element are electrically connected to the conducting metal layers formed on the one surface of the ceramic supporting substrate. The conducting metal layers are in turn connected to projecting leads extending outwardly of the evacuated housing and adapted to be connected to a printed circuit of the timepiece.
A structure of a watch case, which comprises a watchglass, a case band member composed of a cemented carbide alloy and having a flange formed at an upper portion thereof and an annular surface formed at a lower portion of the flange, a watchglass supporting ring brazed to the case band member and having an upper surface for supporting a bottom surface of the watchglass, a packing for providing a waterproof and a back cover secured to the case band member. The packing is provided between the outer periphery of the watchglass and an annular groove. The annular groove is formed by the flange and annular surface of the case band member and the upper surface of the watchglass supporting ring.
A tuning fork-type quartz vibrator having leg members of a length of below six millimeters and a thickness/width ratio below one reveals the zero temperature coefficient at temperatures appearing within a wrist watch carried by a human body. The vibrator also has a favorable low series resonant impedance.
A mechanism and method for supporting a tuning fork-type quartz crystal element which is arranged to fix the common connecting section of a pair of arms of the subject quartz crystal element having a substantially U-shape directly to a base member supporting the element by a particular adhesive agent having an acoustic impedance different from that of the quartz crystal element, thereby preventing a mechanical vibration energy from being transmitted during vibration of the quartz crystal element to the base member and supporting the quartz crystal element with the greatest possible stability and strength on the base member against external mechanical vibrations and shocks.
A lithium tantalate (LiTaO.sub.3) vibrator comprises a lithium tantalate crystal vibratable in the flexural mode and having an electro-mechanical coupling factor within the range 0.04 to 0.10. The crystal may have a tuning fork shape cut from a Z-plate turned an angle of 48.degree. to 55.degree. around the X-axis.
A multifunctional crystal unit in which in the same container constituted by a container body having a recess therein and a cover, a plurality of crystal blanks are hermetically encapsulated. In the container, the crystal blanks are respectively held in different spaces, which are isolated from one another by a shielding member. Hereby, respective crystal blanks are electrically shielded from one another. As the plurality of crystal blanks, a crystal blank of AT cut for generating a communication frequency signal, and a tuning fork type crystal blank for generating a clock signal are preferably used.
