Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide. The linear actuator is also provided with a rod erected at a central axis part of the inner tube and forming an annular space between the rod and the inner tube, a rod guide provided at an extreme end of the rod in sliding contact with an inner surface of the outer tube, a plurality of permanent magnets arranged along an axial direction in the rod, and a plurality of coils retained by the outer tube so as to face the permanent magnets. A cross-sectional area of an outer periphery of the inner tube along which the outer tube slides and a cross-sectional area of an inner periphery of the outer tube along which the rod guide slides are set to be equal.

Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide. The linear actuator is also provided with a rod erected at a central axis part of the inner tube and forming an annular space between the rod and the inner tube, a rod guide which slides along an inner surface of the outer tube and guides the rod along an axial direction, a plurality of permanent magnets arranged along the axial direction in the rod, and a plurality of coils retained by the outer tube so as to face the permanent magnets. A cooling fluid is filled in an internal space formed between the outer tube and the inner tube.

Abstract: A linear actuator includes a first tube, a second tube inserted into the first tube to be free to slide, a rod fixed at one end of the rod to the first tube, a rod guide provided on the other end of the rod so as to slide relative to the second tube, a plurality of permanent magnets held by the rod, a holder that is fitted into the second tube and holds a plurality of coils, a first chamber defined between one end of the holder and an end portion of the first tube, and a second chamber defined between the other end of the holder and the rod guide. An insertion hole which connects the first chamber to the second chamber and through which the rod passes is formed in the holder. A connecting groove that connects the first chamber to the second chamber is formed in the second tube to extend in an axial direction.

Abstract: A linear actuator that is configured to be extended/contracted by relatively displacing a first tube and a second tube in an axial direction, includes a rod that is provided inside the first tube, a plurality of permanent magnets that are held in the rod so as to be arranged in the axial direction; a stopper that is provided on a tip-end portion of the rod, a coil that is provided inside the second tube so as to face the permanent magnets, and a stopper receiving portion that is provided on the second tube so as to face the stopper, wherein the relative displacement between the first tube and the second tube in the extension direction is restricted by bringing an extension-direction-side end surface of the stopper into contact with the stopper receiving portion at a fully extended position.

Abstract: A linear actuator includes a first tube, a second tube inserted into the first tube to be free to slide, a rod fixed at one end of the rod to the first tube, a rod guide provided on the other end of the rod so as to slide relative to the second tube, a plurality of permanent magnets held by the rod, a holder that is fitted into the second tube and holds a plurality of coils, a first chamber defined between one end of the holder and an end portion of the first tube, and a second chamber defined between the other end of the holder and the rod guide. An insertion hole which connects the first chamber to the second chamber and through which the rod passes is formed in the holder. A connecting groove that connects the first chamber to the second chamber is formed in the second tube to extend in an axial direction.

Abstract: A linear actuator includes a first tube and a second tube inserted into the first tube to be free to slide. The first tube includes an outer tube and a cap provided detachably on an end portion of the outer tube, while the second tube includes a base portion and an inner tube provided detachably on the base portion and inserted into the outer tube to be free to slide. A first sliding member that slides against an outer periphery of the inner tube is provided on an inner periphery of one end of the outer tube. A second sliding member that slides against an inner periphery of the outer tube is provided on an outer periphery of an end portion of the inner tube corresponding to the other end of the outer tube.

Abstract: A linear actuator that is configured such that a first tube and a second tube are relatively displaced in an axial direction, includes a rod that is provided in the first tube and whose one end is fixed to an end portion of the first tube, a plurality of permanent magnets that are held by the rod so as to be arranged in the axial direction, and a tubular coil holder that is provided in the second tube and holds a coil that faces the permanent magnets, wherein the first tube has a first linear guide portion with a cylindrical surface that extends in the axial direction around the coil holder, and the second tube has a second linear guide portion with a cylindrical surface that is faced to the first linear guide portion without a gap therebetween so as to be slidably fitted therewith.

Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide axially. A rod is erected at a central axis part of the inner tube, forming an annular space between the rod and the inner tube. Permanent magnets are retained along an axial direction in the rod, and a holder is fixed to the outer tube for retaining coils which are disposed face to face with the permanent magnets. The holder includes a cylindrical coil holding portion inserted in the annular space such that an extreme end of the cylindrical coil holding portion can move further into and backward from the annular space. The coil holding portion retains the coils within an inner peripheral surface, and a flange portion joined directly to a proximal end of the coil holding portion is fixed to the outer tube.

Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide. The linear actuator is also provided with a rod erected at a central axis part of the inner tube and forming an annular space between the rod and the inner tube, a rod guide which slides along an inner surface of the outer tube and guides the rod along an axial direction, a plurality of permanent magnets arranged along the axial direction in the rod, and a plurality of coils retained by the outer tube so as to face the permanent magnets. A cooling fluid is filled in an internal space formed between the outer tube and the inner tube.

Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide. The linear actuator is also provided with a rod erected at a central axis part of the inner tube and forming an annular space between the rod and the inner tube, a rod guide provided at an extreme end of the rod in sliding contact with an inner surface of the outer tube, a plurality of permanent magnets arranged along an axial direction in the rod, and a plurality of coils retained by the outer tube so as to face the permanent magnets. A cross-sectional area of an outer periphery of the inner tube along which the outer tube slides and a cross-sectional area of an inner periphery of the outer tube along which the rod guide slides are set to be equal.

Abstract: A linear actuator for generating a thrust force for relatively displacing an outer tube and an inner tube in an axial direction includes a rod standing in an axial center part of the inner tube, a plurality of permanent magnets held side by side in an axial direction by the rod, a plurality of coils facing the permanent magnets, and a holder that is fixed to the outer tube and holds the plurality of coils. The holder includes a tubular coil holding portion that is provided in an annular space formed between the rod and the inner tube and holds the coils. A clearance is formed between the outer periphery of the coil holding portion and the inner periphery of the inner tube.

Abstract: Magnetic toner involves magnetic powder 1 having the particle shape of an octahedron 2 that is a convex polyhedron surrounded by eight triangles as a basis, each of the vertexes and edges of the octahedron being in a curved surface shape, and having a portion 3 that can be taken as a straight line on the outer periphery of its projected image. Therefore, the magnetic toner is superior in both two contradictory properties, that is the property of making it easy for a charging amount to quickly rise as well as improving the charging amount and the property of making it difficult for charge-up to occur, thereby making it possible to form a good image under a wide environment. In an image forming method, an electrostatic latent image is developed into a toner image by a magnetic one-component jumping developing method using the magnetic toner.

Abstract: The toner of the present invention is characterized in that the charges rise up rapidly, the charge quantity is not insufficient nor excessive, the photoreceptor contamination is minimized and the toner is endurable under harsh conditions and against the high stress usage. The magnetic particle contained in the toner is of average particle size 0.01 ?m through 0.50 ?m, is of octahedron shape that is a convex polyhedron surrounded by eight triangles as a basis, each of vertexes and edges of the octahedron being in a curved surface shape and having a portion that can be taken as a straight line on the outer periphery of a projected image of said octahedron. The sphericity of the toner is 0.94 through 0.98. Here, the sphericity is defined by C2/C1, where C1 is a circumferential length of an image projected on a plane and C2 is a circumferential length of an assumed circle area as same as that of the projected image. Further, a number content of the toner of particle size 0.6 ?m through 2.

Abstract: The object is to provide a magnetic toner with which toner scattering, toner spent to carrier, development of scratch streaks by the magnetic brush on the photoreceptor drum can be prevented for a prolonged period and a good image characteristic (in image density and background fogging) can be maintained for a prolonged period, and an image forming method using the magnetic toner. A two-component developer comprising carriers and toner which contains magnetic particle at least in a binder resin thereof, the magnetic particle being of basically polyhedral shaped shape, vertexes and edges of said polyhedral shape being curved surfaces, said shape having peripheral parts taken as straight lines in a projected image thereof, saturation magnetization of said toner in a magnetic field of 79.6 kA/m being 4.0 to 15.

Abstract: Disclosed is a magnetic one-component toner for development of an electrostatic latent image used in a magnetic one-component jumping development system in which a photoconductor is an a-Si photoconductor having a thickness of 30 ?m or less and Rz of a developer carrier is from 2.0 to 6.0 ?m. A cleaning means for removing the toner from the surface of the photoconductor is a cleaning blade. Titanium oxide, as an external additive, is added to the toner. The titanium oxide has a liberation rate within a range from 10 to 22% and contains a low resistance titanium oxide having a volume resistivity within a range from 100 to 107?·cm and a high resistance titanium oxide having a volume resistivity within a range from 108 to 1013?·cm, a mass ratio of the low resistance titanium oxide to the high resistance titanium oxide within a range from 1.3:1 to 4:1.

Abstract: Disclosed is a toner for a developer comprising cylindrical toner particles formed of a toner composition containing at least a binder resin and a releasant as toner components, and an external additive, wherein the cylindrical toner particles have an average circularity of 0.880 or more and 0.930 or less.

Abstract: The developer comprises magnetic toners and the magnetic carriers which forms magnetic ears on the surface of the developing roller. The magnetic toner is of an average particle size 0.01 ?m through 0.50 ?m and is of octahedron shape that is a convex polyhedron surrounded by eight triangles as a basis, each of the vertexes edges of the octahedron shape toner being in a curved surface shape and having a portion that can be taken as a straight line on the outer periphery of a projected image of the octahedron shape toner. The magnetic ears are electrically charged by the friction between the magnetic toner and the magnetic carriers and the magnetic ears on the developing roller are carried to the electrostatic latent image on the photoreceptor. The latent image is developed by the magnetic toners in the magnetic ears, in a small gap between the developing roller and the photoreceptor.

Abstract: An object of the present invention is to provide a toner for development of an electrostatic latent image, which has excellent developability and which is used in an electrophotographic image forming apparatus. One aspect of the present invention pertains to a toner for development of an electrostatic latent image, comprising cylindrical toner particles and titanium oxide particles added externally to the cylindrical toner particles, wherein the titanium oxide particles have an average primary particle size within a range from 10 to 100 nm, and the titanium oxide particles have a specific volume resistivity value within a specific range. Such a toner for development of an electrostatic latent image suppresses an image deletion phenomenon and is excellent in charge characteristics, and also exerts an extremely excellent effect on long-term printing durability.

Abstract: Disclosed is a toner for use in an image forming apparatus using an amorphous silicon photoconductor as a latent image carrier, and having a cleaning blade for removing the toner remaining on the photoconductor after a transfer step. The toner has a friction coefficient with the photoconductor in a range of 0.3 to 0.6. At least inorganic fine particles such as titanium oxide are externally added to the toner. The inorganic fine particles have a number-average primary particle size of 30 nm or more.

Abstract: Disclosed is a toner used for an image forming apparatus, comprising an organic photoreceptor as a latent image supporting material and a cleaning blade for removing a residual toner on the organic photoreceptor after a transfer process, wherein the friction coefficient between the organic photoreceptor and the toner is from 0.30 to 0.65, the toner contains at least one kind of inorganic fine particles on the surface, and one of the inorganic fine particles is made of silica.