Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A vibrating element includes: a vibrating body having frequency temperature dependency; and a temperature characteristic correcting part provided on a surface of the vibrating body. The temperature characteristic correcting part has a temperature characteristic of at least one of a Young's modulus and a thermal expansion coefficient and is expressed by a temperature characteristic curve which has at least one of an inflection point and an extremal value. In the vibrating element, a temperature of at least one of the inflection point and the extremal value is within an operating temperature range of the vibrating body.

Abstract: A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.

Abstract: A bearing stiffness of a sintered metal sleeve is prevented from lowering. A sleeve includes an inner section formed of metal powder for sintering and a resin for impregnation, and a surface deformation section which covers a surface of the inner section and is formed by shot blast process. Since the surface deformation section is formed by the shot blast process, the number of pores formed between the metal powder for sintering near the surface can be reduced. In this way, a supporting pressure at a bearing portion can be prevented from being released out through the pores, and the bearing stiffness can be prevented from lowering.

Abstract: A piezoelectric resonator includes a piezoelectric resonator element having a resonating arm and a metal film that is formed on the resonating arm; a package including a bottom part on which the piezoelectric resonator element is fixed and a frame wall that surrounds the bottom part, and having an opening above the bottom part; and a lid including a frame in which a through hole is provided and an optically transparent part that has an upper face and a lower face of the frame and is disposed at the through hole, the through hole penetrating a front face and a back face, the lower face of the optically transparent part being disposed so as to oppose the metal film, and the lid closing the opening of the package such that the lid overlaps with the bottom part and the frame wall, the through hole having a curved inner wall face whose curved face is coupled with at least one of the front face and the back face at least one opening edge of the front face and the back face and a vertical inner wall face that is pro

Abstract: A vibrating element includes: a vibrating body having frequency temperature dependency; and a temperature characteristic correcting part provided on a surface of the vibrating body. The temperature characteristic correcting part has a temperature characteristic of at least one of a Young's modulus and a thermal expansion coefficient and is expressed by a temperature characteristic curve which has at least one of an inflection point and an extremal value. In the vibrating element, a temperature of at least one of the inflection point and the extremal value is within an operating temperature range of the vibrating body.

Abstract: A piezoelectric resonator includes a piezoelectric resonator element having a base portion and a resonating arm extending from the base portion, a package including a bottom to which the piezoelectric resonator element is fixed and a frame wall that surrounds the bottom and having an opening above the bottom, and a lid for closing the opening of the package. In this piezoelectric resonator, the lid includes a main body having a through-hole formed therein, a flange formed to surround a periphery of the main body and to be thinner than the main body, and an optically transparent member located in the through-hole. The flange has a joining portion with an upper end surface of the frame wall, and the main body projects in a direction from the flange to the bottom in a thickness direction. Also, the through-hole is at a position displaced in a first direction approaching a first end of the main body from a center of the main body.

Abstract: A piezoelectric resonator includes a piezoelectric resonator element having a base portion and a resonating arm extending from the base portion, a package including a bottom to which the piezoelectric resonator element is fixed and a frame wall that surrounds the bottom and having an opening above the bottom, and a lid for closing the opening of the package. In this piezoelectric resonator, the lid includes a main body having a through-hole formed therein, a flange formed to surround a periphery of the main body and to be thinner than the main body, and an optically transparent member located in the through-hole. The flange has a joining portion with an upper end surface of the frame wall, and the main body projects in a direction from the flange to the bottom in a thickness direction. Also, the through-hole is at a position displaced in a first direction approaching a first end of the main body from a center of the main body.

Abstract: The hydrodynamic bearing device has a sleeve composed of a sintered material and having a compression-absorbing space inside the sleeve, the sleeve having a bearing hole in the center thereof; a shaft rotatably inserted into the bearing hole; a bearing portion formed between the bearing hole and the shaft; a hydrodynamic groove formed on at least one of the internal peripheral surface of the bearing hole and the external peripheral surface of the shaft; a concavity having one or more steps and formed to one end of the sleeve in the axial direction; a convexity formed to the other end of the sleeve in the axial direction, the convexity having a shape similar to the concavity; and a lubricating fluid filled in the gap of the bearing portion. The hydrodynamic bearing device has a readily obtainable predetermined shape precision, the internal density of the sintered material is made uniform, and lubricating fluid therein does not leak from the surface.

Abstract: A hydrodynamic bearing device including a sleeve (1), a shaft (2), and oil (100). With respect to the sleeve (1), a stepped portion (1b) provided at one end and an inner peripheral face (1e) extending linearly in the axial direction and continuously with the stepped portion (1b) are formed by a working method that involves the use of a metal mold. The shaft (2) is inserted so as to be capable of relative rotation with respect to the inner peripheral face (1e) of the sleeve (1). The oil fills the space formed between the inner peripheral face of the sleeve and the outer peripheral face of the shaft. Dynamic pressure generation grooves (9a and 9b), which open in the axial direction at at least one end in the axial direction of the inner peripheral face (1e) and are continuous in the axial direction from one end, are formed in the inner peripheral face.

Abstract: A spindle motor including a rotor hub which is rotationally driven by a magnetic action of a rotational magnetic field generated when a current is applied to a wire wound around teeth of a stator core and a magnetic field of a magnet provided on a rotor. Herein, the stator core formed by laminating magnetic steel plates is mounted to an outer periphery of a supporting part of a rotation support shaft of the rotor hub, and the supporting part is made of sintered metal containing a ferromagnetic material. This spindle motor can suppress generation of vibration and noise even when it is reduced in size.

Abstract: A spindle motor including a rotor hub which is rotationally driven by a magnetic action of a rotational magnetic field generated when a current is applied to a wire wound around teeth of a stator core and a magnetic field of a magnet provided on a rotor. Herein, the stator core formed by laminating magnetic steel plates is mounted to an outer periphery of a supporting part of a rotation support shaft of the rotor hub, and the supporting part is made of sintered metal containing a ferromagnetic material. This spindle motor can suppress generation of vibration and noise even when it is reduced in size.

Abstract: A hydrodynamic bearing device comprises a sleeve composed of a sintered member, a shaft that is inserted in a state of being capable of relative rotation into a bearing hole provided to the sleeve, and a hydrodynamic groove formed in the outer peripheral surface of the shaft and/or the inner peripheral surface of the sleeve. The sleeve has a surface porosity of 1.5% or less, and the ridge width is at least 0.10 mm.

Abstract: A sleeve for a hydrodynamic bearing device, a hydrodynamic bearing device equipped with the sleeve, a spindle motor, information recording and reproducing and processing apparatus, and a method for manufacturing a sleeve for a hydrodynamic bearing device are provided that are capable of reducing costs through appropriate sealing treatment. The sleeve for a hydrodynamic bearing device has an inner layer and a surface layer. The inner layer is formed by sintering metal powder for sintering use. The surface layer is formed on a surface of the inner layer and includes diiron trioxide (Fe2O3). Sealing treatment is carried out by forming a surface layer including diiron trioxide (Fe2O3) on a surface of a sleeve for a hydrodynamic bearing device that is porous.

Abstract: A piezoelectric resonator includes a piezoelectric resonator element having a resonating arm and a metal film that is formed on the resonating arm; a package including a bottom part on which the piezoelectric resonator element is fixed and a frame wall that surrounds the bottom part, and having an opening above the bottom part; and a lid including a frame in which a through hole is provided and an optically transparent part that has an upper face and a lower face of the frame and is disposed at the through hole, the through hole penetrating a front face and a back face, the lower face of the optically transparent part being disposed so as to oppose the metal film, and the lid closing the opening of the package such that the lid overlaps with the bottom part and the frame wall, the through hole having a curved inner wall face whose curved face is coupled with at least one of the front face and the back face at least one opening edge of the front face and the back face and a vertical inner wall face that is pro