摘要:
Disclosed herein is a spindle motor including: a shaft forming the center of rotation of the motor; a sleeve receiving the shaft therein and rotatably supporting the shaft; a thrust plate press-fitted into the shaft so as to be perpendicular to an axial direction of the shaft; and a sealing cap spaced apart from the thrust plate in an upward axial direction and bent to enclose an outer side surface of the sleeve to thereby be coupled to the thrust plate, wherein the sealing cap is provided with a sealing part having concave parts and convex parts alternately formed along an inner peripheral surface thereof in a radial direction.
摘要:
There are provided a hydrodynamic bearing assembly and a spindle motor including the same. The hydrodynamic bearing assembly includes: a sleeve including a shaft hole to have a shaft rotatably installed therein; and a cover member covering the shaft hole at a lower portion of the shaft hole in an axial direction, wherein an inner surface of the sleeve is provided with depression parts depressed in an outer diameter direction between upper and lower portions of the sleeve and portions in which radial bearings are formed, such that the portions in which the radial bearings are formed are provided with bearing closure adhesion parts allowing the portions in which the radial bearings are formed to be closer to the shaft than portions other than the portions in which the radial bearings are formed.
摘要:
There are provided a hydrodynamic bearing assembly and a spindle motor including the same. The hydrodynamic bearing assembly includes: a sleeve including a shaft hole to have a shaft rotatably installed therein; and a cover member covering the shaft hole at a lower portion of the shaft hole in an axial direction, wherein an inner surface of the sleeve is provided with depression parts depressed in an outer diameter direction between upper and lower portions of the sleeve and portions in which radial bearings are formed, such that the portions in which the radial bearings are formed are provided with bearing closure adhesion parts allowing the portions in which the radial bearings are formed to be closer to the shaft than portions other than the portions in which the radial bearings are formed.
摘要:
Disclosed herein is an inertial sensor including: a membrane; a mass body provided under the membrane; a plurality of patterned magnets provided under the mass body; and a magnetoresistive element provided to be spaced apart from the mass body and measuring static DC acceleration acting on the mass body through resistance changed according to magnetic fields of the plurality of patterned magnets. The plurality of patterned magnets and the magnetoresistive element are included, thereby making it possible to measure static DC acceleration (particularly, gravity acceleration) that is difficult to measure using an existing to piezoelectric element.
摘要:
There is provided an electric double layer capacitor including: an exterior case having a housing space provided therein and formed of insulating resin; first and second external terminals buried in the exterior case, each having a first surface exposed to the housing space and a second surface exposed to an outside of the exterior case; and a chip-type electric double layer capacitor cell disposed in the housing space and electrically connected to the first surface. The chip-type electric double layer capacitor cell includes first and second electrodes facing each other and having electricity of opposite polarities applied thereto, at least one induction electrode layer disposed between the first and second electrodes and having no electricity applied thereto, and first and second separators disposed between the first electrode and the induction electrode layer and between the second electrode and the induction electrode layer, respectively.
摘要:
Disclosed herein is an inertial sensor, including: a membrane; a mass body disposed under the membrane; a sensing unit formed on the membrane and including a piezoelectric body; and a spring constant control unit formed to be spaced apart from the sensing unit and including a piezoelectric body. According to the preferred embodiment of the present invention, the DC acceleration (in particular, gravity acceleration) can be measured by using the change in the spring constant without changing the structure of the inertial sensor including the piezoelectric material of the prior art.
摘要:
Disclosed herein is an inertial sensor including: a membrane; first and second driving units provided in a first axis direction (an X axis direction) so as to be symmetrical to each other based on a predetermined point of the membrane to thereby vibrate while being expanded and contracted in the first axis direction; and third and fourth driving units provided in a second axis direction (a Y axis direction) perpendicular to the first axis direction so as to be symmetrical to each other based on a predetermined point of the membrane to thereby vibrate while being expanded and contracted in the second axis direction, wherein the first and second driving units have different vibration frequencies so that they vibrate while being expanded and contracted in the opposite manner and then vibrate while being expanded and contracted in the same manner.
摘要:
Disclosed herein is an inertial sensor. The inertial sensor includes a sensing unit and a driving-mass-position initialization module. The sensing unit includes a driving mass, a flexible board unit which displaceably supports the driving mass, and a support which supports the flexible board unit to allow the driving mass to move in a suspended state. The flexible board unit has driving electrodes which move the driving mass, and sensing electrodes which sense the movement of the driving mass. The driving-mass-position initialization module includes a position initialization member which reciprocates to initialize the position of the driving mass, and a coil unit which surrounds the position initialization member. An initialization-member-receiving depression is formed in the driving mass. The shape of the initialization-member-receiving depression corresponds to that of the position initialization member.
摘要:
Disclosed herein is an inertial sensor. The inertial sensor according to a preferred embodiment of the present invention includes: a plate-shaped membrane; a mass body provided under the membrane; posts provided under an outside edge of the membrane and surrounding the mass body; a piezoelectric body formed on the membrane; sensing electrodes formed on the piezoelectric body; driving electrodes formed on an outer circumference of the sensing electrodes, wherein tri-axis angular velocity can be measured without time division by a driving control unit continuously applying first driving voltage and second driving voltage that are is AC driving voltage having a phase difference of 90°.
摘要:
Disclosed herein is an inertial sensor including: a membrane; first and second driving units provided in a first axis direction (an X axis direction) so as to be symmetrical to each other based on a predetermined point of the membrane to thereby vibrate while being expanded and contracted in the first axis direction; and third and fourth driving units provided in a second axis direction (a Y axis direction) perpendicular to the first axis direction so as to be symmetrical to each other based on a predetermined point of the membrane to thereby vibrate while being expanded and contracted in the second axis direction, wherein the first and second driving units have different vibration frequencies so that they vibrate while being expanded and contracted in the opposite manner and then vibrate while being expanded and contracted in the same manner.