Abstract: A structure comprises a piezoelectric ceramics plate formed by two plate-shaped piezoelectric ceramics elements which are layered and joined to each other with inverse polarization, in which electricity is generated by beating one or both surface of the piezoelectric ceramics plate. Therefore, an excellent generating efficiency is obtained.

Abstract: According to the invention, there is provided a stepping motor comprising a laminate type torsion actuator having a pair of cylindrical outer peripheries to be torsionally displaced relative to each other, a cylindrical fixed member surrounding said laminate type torsion actuator with certain space therebetween, first longitudinally vibrating elements placed between said fixed member and one of the cylindrical outer peripheries of said laminate type torsion actuator for selectively connecting or separating the fixed member and the torsion actuator through its elongation or contraction, second longitudinally vibrating elements placed between said fixed member and the other cylindrical peripheries of said torsion actuator with certain space therebetween for selectively connecting or separating the fixed member and the torsion actuator through its elongation or contraction with a phase inverse to that of the first elements.

Abstract: An electrostriction motor provided with an oscillator having an electrostriction element bonded to an elastic solid, and a moving solid contacted with the phase boundary of the elastic solid of the oscillator. The electrostriction element is continuously polarized in the moving direction of said moving solid to include a directly-expanded and -contracted pole to which a cycle voltage is applied, and dependently-expanded and -contracted poles which are positioned on right and left sides of the directly-expanded and -contracted pole, and it is also polarized in such a way that the directly-expanded and -contracted pole and one of the dependently-expanded and -contracted poles have the same polarity, while the remaining dependently-expanded and -contracted pole has a polarity different from that of the directly-expanded and -contracted pole. Therefore, the electrostriction motor can be driven by a cycle voltage having a single phase, and its supply power circuit and wiring can be made simpler accordingly.

Abstract: An apparatus for heat-treating pipes comprising a furnace chamber for accommodating a plurality of pipes as arranged in parallel, a chain conveyor disposed in the furnace chamber for transporting the pipes in a direction at right angles to the axes of the pipes, and a plurality of stopper means for stopping the pipes intermittently at suitably spaced-apart positions in the path of transport by the chain conveyor and causing each of the pipes to rotate about its own axis in cooperation with the chain conveyor. Since the pipe is intermittently stopped and rotated about its own axis during heat treatment, the pipe is free of thermal deformation to an elliptical shape. Pipes can be heat-treated in succession in a small space, therefore with a very high efficiency. The motion of the chain conveyor is utilized for rotating the pipe without necessitating any additional device for the rotation.