Abstract: To reduce assembly man-hours of a planetary gear device by devising a structure of a carrier, disclosed is a carrier of a planetary gear device 1 is formed with a gear housing space for housing a sun gear and a planetary gear. The gear housing space is formed between a pair of gear support parts rotatably supporting the planetary gear by a gear support shaft. The pair of gear support parts are integrally connected by a plurality of beams. The beam has a virtual plane orthogonal to a rotation axis of the sun gear as an x-y plane, and a radial direction of a direction extending radially from the rotation axis along the x-y plane is formed along a radial direction at a radially outer position of the sun gear. The planetary gear is located between the beams.

Abstract: A gear reduction mechanism (1) includes a drive gear (10) having a rotation axis (L1), and a driven gear (20) driven in mesh with the drive gear (10) and having a rotation axis (L2) that is noncoplanar with the rotation axis (L1). The drive gear (10) is provided with spiral teeth, each having a tooth trace of a spiral curve having a spiral center on the rotation axis (L1) and a constant radial pitch, when viewed in the direction of the rotation axis (L1). Furthermore, the tooth profile of the driven gear (20) is set, considering a tangent angle that changes momentarily as the drive gear (10) rotates.

Abstract: To reduce assembly man-hours of a planetary gear device by devising a structure of a carrier, disclosed is a carrier of a planetary gear device 1 is formed with a gear housing space for housing a sun gear and a planetary gear. The gear housing space is formed between a pair of gear support parts rotatably supporting the planetary gear by a gear support shaft. The pair of gear support parts are integrally connected by a plurality of beams. The beam has a virtual plane orthogonal to a rotation axis of the sun gear as an x-y plane, and a radial direction of a direction extending radially from the rotation axis along the x-y plane is formed along a radial direction at a radially outer position of the sun gear. The planetary gear is located between the beams.

Abstract: A gear device includes a first double helical gear, a two-step gear, a second spur gear, and an intermediate shaft The two-step gear includes a second double helical gear meshing with the first double helical gear, and a first spur gear on a back surface side of the second double helical gear. The second spur gear meshes with the first spur gear. A housing includes a shaft support hole and a meshing guide groove. The shaft support hole houses one end side of the intermediate shaft. The meshing guide groove meshes the second double helical gear with the first double helical gear by guiding the intermediate shaft along a pitch circle of the second spur gear to a proximity of the shaft support hole while maintaining the first spur gear meshing with the second spur gear. The meshing guide groove rises up at the proximity of the shaft support hole.

Abstract: A gear reduction mechanism (1) includes a drive gear (10) having a rotation axis (L1), and a driven gear (20) driven in mesh with the drive gear (10) and having a rotation axis (L2) that is noncoplanar with the rotation axis (L1). The drive gear (10) is provided with spiral teeth, each having a tooth trace of a spiral curve having a spiral center on the rotation axis (L1) and a constant radial pitch, when viewed in the direction of the rotation axis (L1). Furthermore, the tooth profile of the driven gear (20) is set, considering a tangent angle that changes momentarily as the drive gear (10) rotates.

Abstract: A gear device includes a first double helical gear, a two-step gear, a second spur gear, and an intermediate shaft The two-step gear includes a second double helical gear meshing with the first double helical gear, and a first spur gear on a back surface side of the second double helical gear. The second spur gear meshes with the first spur gear. A housing includes a shaft support hole and a meshing guide groove. The shaft support hole houses one end side of the intermediate shaft. The meshing guide groove meshes the second double helical gear with the first double helical gear by guiding the intermediate shaft along a pitch circle of the second spur gear to a proximity of the shaft support hole while maintaining the first spur gear meshing with the second spur gear. The meshing guide groove rises up at the proximity of the shaft support hole.

Abstract: It is an object of the present invention to approximate of life of each resin double helical gear of a gearing resin double helical gear pair to each other by effectively increasing the strength of the tooth of the resin double helical gear with the higher rotational speed; and to lengthen life of the gearing resin double helical gear pair by effectively increasing the strength of the tooth of the resin double helical gear that comes to the end of its life earlier due to stress concentration out of the gearing resin double helical gear pair. A resin double helical gear pair includes a first resin double helical gear and a second resin double helical gear with the larger diameter gearing into the first double helical gear. The first double helical gear is formed so that at least an addendum modification coefficient of a peak of a chevron tooth is larger than addendum modification coefficients of other sections.

Abstract: A high-strength, high-precision injection-molded gear in which resin flow regulating projections that partially thicken a web are formed in a position on a side surface side of the web between pin point gates and a teeth section such as to project from the side surface of the web. The resin flow regulating projections are formed such that a center section thereof, the highest in height, is on a radial direction line extending from the pin point gates in the outward radial direction and the height gradually decreases away from the position on the radial direction line in a circumferential direction of the web.

Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an ink jet printer, and a gear train for an ink jet printer using the same. The gear train 2 for an ink jet printer 1 includes an output gear 5 of a motor 3, a first idle gear 6 meshing with the output gear 5, a second idle gear 7 rotatable with the first idle gear 6, and a driven gear 8 which is mounted on a roller shaft 13 so as to be rotatable therewith and which meshes with the second idle gear 7, wherein a resin double helical gear 101 is used as each of the output gear and the first idle gear, and a spur gear is used as each of the second idle gear and the driven gear. The resin double helical gear may have a meshing relief portion 113 by cutting a chevron-shaped top portion 104 in a central portion 103 in face width directions, which is arranged in a butt portion 113 between a first die 108 and a second die 110, from a tooth crest to a portion near a bottom land so as to decrease a tooth thickness.

Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an image forming system, such as an ink jet printer, which is arranged in the vicinity of an operator, and a gear train using the same and having a smaller number of parts. The gear train 2 for ink jet printer 1 includes a first resin double helical gear 5 which is mounted on an output shaft 4 of a motor 3 so as to be rotatable therewith, and a second resin double helical gear 6 which is mounted on a paper feeding roller shaft 7 so as to be rotatable therewith and which meshes with the first resin double helical gear 5.

Abstract: A high-strength, high-precision injection-molded gear is provided in which, regardless of the thickness of a web, the speed of flow of molten resin injected into a cavity from pin point gates can be equalized and a weld line formed in a merging section of the molten resin can be sufficiently reduced. Resin flow regulating projections 3 that partially thicken a web 7 are formed in a position on a side surface 11 side of the web 7 between pin point gates 12 and a teeth section 8 such as to project from the side surface 11 of the web 7. The resin flow regulating projections 3 are formed such that a projection height is the highest on a radial direction line 14 extending from the pin point gates 12 in the outward radial direction and gradually decreases away from the position on the radial direction line 14 in a circumferential direction of the web 7.

Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an image forming system, such as an ink jet printer, which is arranged in the vicinity of an operator, and a gear train using the same and having a smaller number of parts. The gear train 2 for ink jet printer 1 includes a first resin double helical gear 5 which is mounted on an output shaft 4 of a motor 3 so as to be rotatable therewith, and a second resin double helical gear 6 which is mounted on a paper feeding roller shaft 7 so as to be rotatable therewith and which meshes with the first resin double helical gear 5.

Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an ink jet printer, and a gear train for an ink jet printer using the same. The gear train 2 for an ink jet printer 1 includes an output gear 5 of a motor 3, a first idle gear 6 meshing with the output gear 5, a second idle gear 7 rotatable with the first idle gear 6, and a driven gear 8 which is mounted on a roller shaft 13 so as to be rotatable therewith and which meshes with the second idle gear 7, wherein a resin double helical gear 101 is used as each of the output gear and the first idle gear, and a spur gear is used as each of the second idle gear and the driven gear. The resin double helical gear may have a meshing relief portion 113 by cutting a chevron-shaped top portion 104 in a central portion 103 in face width directions, which is arranged in a butt portion 113 between a first die 108 and a second die 110, from a tooth crest to a portion near a bottom land so as to decrease a tooth thickness.

Abstract: A gear train for an ink jet printer includes an output gear of a motor, a first idle gear meshing with the output gear, a second idle gear rotatable with the first idle gear, and a driven gear which is mounted on a roller shaft so as to be rotatable therewith and which meshes with the second idle gear. A resin double helical gear is used as each of the output gear and the first idle gear, and a spur gear is used as each of the second idle gear and the driven gear. The resin double helical gear may have a meshing relief portion formed by cutting a chevron-shaped top portion in a central portion in face width directions, which is arranged in a butt portion between a first die and a second die, from a tooth crest to a portion near a bottom lane so as to decrease a tooth thickness.

Abstract: A plastic molded gear capable of reducing teeth knocking noises due to backlash during engagement. A protruding portion 5 for eliminating backlash is formed so as to protrude from both end portions in facewidth directions on one tooth flank 6 of each tooth 2, and the protruding portion 5 is not formed on the other tooth flank 12 of the tooth 2. If the protruding portion 5 is elastically deformed so as to absorb backlash, the protruding portion 5 has the same plane as that of the one tooth flank 6, and the other tooth flank 12 of the tooth 2 serves as a main power transmission surface. With this construction, the protruding portion 5 elastically contacts the tooth flank of a companion gear engaged with the plastic molded gear, so that the elastic deformation of the protruding portion 5 absorbs rotational energy of the companion gear during intermittent rotation.

Abstract: It is an object of the present invention to approximate of life of each resin double helical gear of a gearing resin double helical gear pair to each other by effectively increasing the strength of the tooth of the resin double helical gear with the higher rotational speed; and to lengthen life of the gearing resin double helical gear pair by effectively increasing the strength of the tooth of the resin double helical gear that comes to the end of its life earlier due to stress concentration out of the gearing resin double helical gear pair. A resin double helical gear pair includes a first resin double helical gear and a second resin double helical gear with the larger diameter gearing into the first double helical gear. The first double helical gear is formed so that at least an addendum modification coefficient of a peak of a chevron tooth is larger than addendum modification coefficients of other sections.

Abstract: A gearing apparatus having a driving gear G0 of a predetermined tooth width, and secured to an input shaft having an axis thereof, a first small diameter driven gear G1 formed of a face gear secured to an end of an output shaft having an axis thereof perpendicularly intersecting with the axis of the input shaft and engaged with the driving gear at a portion within the tooth width of the driving gear; and a second large diameter driven gear G2 formed of a face gear secured to an end portion of another output shaft having an axis thereof perpendicularly intersecting with the axis of the input shaft and engaged with the driving gear at a remaining portion within the tooth width. The output shafts are coaxial and are extended in opposite directions, and the rotation of the driven gears G1 and G2 according to the rotation of the driving gear G0 are mutually opposite.

Abstract: In a gear having teeth 2 on the outer periphery thereof, each of the teeth 2 has an elastically deformable overhanging portion 7 which is formed on one end face 6 in facewidth directions of a corresponding one of the teeth 2 so as to protrude from a portion near a tooth flank 8 of the corresponding one of the teeth 2 toward adjacent one of the teeth 2, and a portion of the overhanging portion 7 contacting one of teeth of a companion gear is formed so as to have the same plane as that of the tooth flank 8 when the overhanging portion 7 is pressed by the one of teeth of the companion gear to be elastically deformed.

Abstract: There is provided a plastic molded gear capable of reducing teeth knocking noises due to backlash during engagement. A protruding portion 5 for eliminating backlash is formed so as to protrude from both end portions in facewidth directions on one tooth flank 6 of each tooth 2, and the protruding portion 5 is not formed on the other tooth flank 12 of the tooth 2. If the protruding portion 5 is elastically deformed so as to absorb backlash, the protruding portion 5 has the same plane as that of the one tooth flank 6, and the other tooth flank 12 of the tooth 2 serves as a main power transmission surface. With this construction, the protruding portion 5 elastically contacts the tooth flank of a companion gear engaged with the plastic molded gear, so that the elastic deformation of the protruding portion 5 absorbs rotational energy of the companion gear during intermittent rotation.

Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an image forming system, such as an ink jet printer, which is arranged in the vicinity of an operator, and a gear train using the same and having a smaller number of parts. The gear train 2 for ink jet printer 1 includes a first resin double helical gear 5 which is mounted on an output shaft 4 of a motor 3 so as to be rotatable therewith, and a second resin double helical gear 6 which is mounted on a paper feeding roller shaft 7 so as to be rotatable therewith and which meshes with the first resin double helical gear 5.