Abstract: A hydraulic dynamic bearing has a rotational assembly and a bearing member for rotationally supporting the rotational assembly. The bearing member has a main body having a recess portion and a cover for covering an open end of the recess portion. The rotational assembly has a shaft main body having an end portion extending into the recess of the bearing main body for undergoing rotation relative thereto and a ring member disposed in the recess of the bearing main body. The ring member is connected to the end portion of the shaft main body for rotation therewith. Axial dynamic pressure generating grooves are formed in upper and lower surface portions of the ring member for generating axial dynamic pressure during rotation of the rotational assembly. Radial dynamic pressure generating grooves are formed in an outer peripheral surface portion of the ring member for generating radial dynamic pressure during rotation of the rotational assembly.

Abstract: A measurement device has a laser light source for irradiating a laser light, a reflecting mirror for reflecting the laser light irradiated from the laser light source in a preselected direction and/or for scanning the laser light within a preselected angle range, and an oscillating motor for driving the reflecting mirror to reflect the laser light in the preselected direction and/or oscillating the reflecting mirror within the preselected angle range to scan the laser light. The oscillating motor has a main shaft for undergoing rotational oscillating movement and for supporting the reflecting mirror for rotational oscillating therewith, a connecting device for removably connecting the reflecting mirror to the main shaft, and a detecting device for detecting a rotation angle of the main shaft. A reflector reflects the laser light reflected and/or scanned by the reflecting mirror. A light receiving element receives the laser light reflected by the reflector.

Abstract: A rotary driving device for rotating an object to be rotated, is manufactured by a process of rotating a turntable, for loading the object to be rotated thereon, mounted to a driving part and thereby generating a surface vibration because of rotation of the turntable, and a process of forming a surface vibration absorber part on the turntable corresponding to an amount of the surface vibration.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; developer carrying member for carrying a developer comprising toner particles; a voltage source for applying to the developer carrying member an oscillating voltage having a predetermined frequency; wherein the following is satisfied:.vertline.Vpp-2Vcont.vertline./16Vf.sup.2 <d.sup.2 /.vertline.Q.vertline.where Vpp (V) is a peak-to-peak voltage of the oscillating voltage, Vf (Hz) is the frequency of the oscillating voltage, Vcont (V) is a potential difference between a voltage of a DC component of the oscillating voltage and a potential of an image portion on the image bearing member when a maximum image density is provided, Q (c/kg) is an average triboelectric charge amount of the toner particles, and d (m) is a gap between the image bearing member and the developer carrying member.

Abstract: A developing device for developing an electrostatic latent image includes a rotatable developer carrying member for carrying a developer composed of toner particles and magnetic carrier particles, wherein the developer carrying member rotates through a supply position where the developer is supplied to a surface of the developer carrying member, a regulating position where a regulating member for regulating a thickness of a layer of the developer on the surface is disposed, a developing position where the electrostatic latent image is developed, and a removing position for removing the developer remaining on the surface after a developing operation, in the order named. A stationary magnet is disposed in the developer carrying member.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; developer carrying member for carrying a developer comprising toner particles; a voltage source for applying to the developer carrying member an oscillating voltage having a predetermined frequency; wherein the following is satisfied:.vertline.Vpp-2Vcont.vertline./16Vf.sup.2 <d.sup.2 /.vertline.Q.vertline.where Vpp (V) is a peak-to-peak voltage of the oscillating voltage, Vf (Hz) is the frequency of the oscillating voltage, Vcont (V) is a potential difference between a voltage of a DC component of the oscillating voltage and a potential of an image portion on the image bearing member when a maximum image density is provided, Q (c/kg) is an average triboelectric charge amount of the toner particles, and d (m) is a gap between the image bearing member and the developer carrying member.

Abstract: An image forming apparatus includes an electrophotographic photosensitive member; a light source; a developing device for developing with a developer an electrostatic latent image formed on the photosensitive member by light from the light source, wherein the developer is a one component non-magnetic developer; and a controller responsive to image information to control a continuous light emitting period of the light source per one picture element.