Abstract: There is provided a fuel pump (10) which includes an impeller (20) in a disk-like shape; a casing (18) comprised of a pump cover (14) and a pump body (16) that rotatably accommodate the impeller; and a motor section (70) that drives to rotate the impeller; wherein, on at least one of seal portions of the casing (18) and in its place facing to a series of recesses (20b,20c) of the impeller, a recessed shape (35,36) in a micron order is formed in expectation of a swelling amount of the series of recesses (20b,20c) of the impeller (20).

Abstract: An optical fiber sensor measuring refractive index of a medium with high sensitivity in a wide range. The optical fiber sensor includes an optical fiber causing a transmission loss due to leakage in the clad propagation mode from a portion of a core and a clad where a Bragg grating is provided, a light source permitting light in a wavelength band in the clad propagation mode to enter the optical fiber, and a light-receiving section receiving the transmitted or reflected light transmitted through the core and the clad at the portion where the Bragg grating is provided. The refractive index of the medium to be measured in contact with the clad is measured according to total intensity of the light received by the light-receiving section. The Bragg grating is inclined at a predetermined angle of inclination to the vertical line vertical to the length direction of the optical fiber.

Abstract: The detection device provides with an optical fiber composed of a core, a clad and a fiber jacket. A grating is applied to the core, and the fiber jacket located at the portion to which the grating is applied is removed so that the clad is in contact with a fuel fed to an injector of a vehicle. The detection device also provides with a light source for incidence of a light in a range of clad mode wavelength to the optical fiber, and a light-sensitive part for detecting an intensity of the light transmitting through the region to which the grating is applied. The optical fiber, light source and light-sensitive part are held in a conduit disposed in a fuel tank or between a fuel pump and the injector of the vehicle.

Abstract: An optical fiber sensor measuring refractive index of a medium with high sensitivity in a wide range. The optical fiber sensor includes an optical fiber causing a transmission loss due to leakage in the clad propagation mode from a portion of a core and a clad where a Bragg grating is provided, a light source permitting light in a wavelength band in the clad propagation mode to enter the optical fiber, and a light-receiving section receiving the transmitted or reflected light transmitted through the core and the clad at the portion where the Bragg grating is provided. The refractive index of the medium to be measured in contact with the clad is measured according to total intensity of the light received by the light-receiving section. The Bragg grating is inclined at a predetermined angle of inclination to the vertical line vertical to the length direction of the optical fiber.

Abstract: To provide an optical head and an optical disc device, in which a cover member for radiating and protecting the optical head and a laser light source are of a simple construction, manufacturing efficiency can be increased, and accuracy variation due to assembly of the laser light source such as an optical axis or the like of a laser beam can be suppressed. Therefore, a boss formed on a light source installation portion of a base is engaged with a boss hole formed on a laser light source supporting portion of the cover member, thereby positioning the cover member on the base. In doing so, an internal thread hole formed on the bottom surface of the base is overlapped with a thread hole formed on a cover portion of the cover member. In this state, a bolt is passed through the thread hole to screw in the internal thread hole.

Abstract: An optical head, in which a spring stopper rib, as formed in a slide base, includes a post portion protruding from the upper face of the slide base, and a spring stopper portion for stopping a spring, and in which the spring receiving portion of an actuator has a recess formed for arranging the spring.

Abstract: An optical disk apparatus that includes: a disk drive device having a guide shaft secured to a chassis and an optical pickup which is rotatably attached to the guide shaft and moves along the guide shaft. The optical pickup comprises a lens holder holding an objective lens for emitting a light beam to be projected onto an optical disk and having a sliding hole, a shaft passing through the sliding hole, a focus coil wound around an outer wall of the sliding hole, and a hexagonal magnetic plate fit over the outer wall of the sliding hole so as to be adjacent to the focus coil. One side of the hexagonal magnetic plate is bent toward the focus coil so that the magnetic plate is inclined with respect to a plane having a normal line parallel to a sliding direction of the lens holder.

Abstract: The detection device provides with an optical fiber composed of a core, a clad and a fiber jacket. A grating is applied to the core, and the fiber jacket located at the portion to which the grating is applied is removed so that the clad is in contact with a fuel fed to an injector of a vehicle. The detection device also provides with a light source for incidence of a light in a range of clad mode wavelength to the optical fiber, and a light-sensitive part for detecting an intensity of the light transmitting through the region to which the grating is applied. The optical fiber, light source and light-sensitive part are held in a conduit disposed in a fuel tank or between a fuel pump and the injector of the vehicle.

Abstract: It is an object to save time and effort for operations in assembling and in detaching a radiation cover member when replacing and/or maintaining internal parts as well as to improve the assembling accuracy of the products. In an optical head A having a base 1, an actuator 2, and a cover member 3 for covering the bottom surface of the base 1, on a light source contact portion 321 in a laser light source support portion 32 of the cover member 3, there is formed a convex portion 3211 adapted to be engaged with a key groove 522 that is formed in a flange portion 52 of a laser light source 5.

Abstract: To provide an optical head and an optical disc device, in which a cover member for radiating and protecting the optical head and a laser light source are of a simple construction, manufacturing efficiency can be increased, and accuracy variation due to assembly of the laser light source such as an optical axis or the like of a laser beam can be suppressed. Therefore, a boss formed on a light source installation portion of a base is engaged with a boss hole formed on a laser light source supporting portion of the cover member, thereby positioning the cover member on the base. In doing so, an internal thread hole formed on the bottom surface of the base is overlapped with a thread hole formed on a cover portion of the cover member. In this state, a bolt is passed through the thread hole to screw in the internal thread hole.

Abstract: An optical head, in which a spring stopper rib, as formed in a slide base, includes a post portion protruding from the upper face of the slide base, and a spring stopper portion for stopping a spring, and in which the spring receiving portion of an actuator has a recess formed for arranging the spring.

Abstract: An optical disk apparatus that includes: a disk drive device having a guide shaft secured to a chassis and an optical pickup which is rotatably attached to the guide shaft and moves along the guide shaft. The optical pickup comprises a lens holder holding an objective lens for emitting a light beam to be projected onto an optical disk and having a sliding hole, a shaft passing through the sliding hole, a focus coil wound around an outer wall of the sliding hole, and a hexagonal magnetic plate fit over the outer wall of the sliding hole so as to be adjacent to the focus coil. One side of the hexagonal magnetic plate is bent toward the focus coil so that the magnetic plate is inclined with respect to a plane having a normal line parallel to a sliding direction of the lens holder.