Abstract: A planetary gear device configured by combining a plurality of planetary gear mechanisms includes first and second planetary gear mechanisms sharing a carrier, wherein each planetary gear mechanism is composed of an internal gear Ik (k is an integer equal to or larger than 2) and a planetary gear Pk which is engaged with the internal gear Ik and revolves in a circumferential direction of the internal gear, the planetary gear Pk of each planetary gear mechanism is composed of a spur gear in the form of an external gear, the planetary gears Pk of the planetary gear mechanisms share a central axis or have central axes integrally connected to integrally rotate on a common rotation central axis line or are integrated with each other to integrally rotate on the common rotation central axis line in order to configure the entire planetary gear device as a two-stage gear mechanism, the planetary gear device is configured such that the number of teeth zp1 of a first planetary gear constituting the first planetary gear

Abstract: A planetary gear device configured by combining a plurality of planetary gear mechanisms includes first and second planetary gear mechanisms sharing a carrier, wherein each planetary gear mechanism is composed of an internal gear Ik (k is an integer equal to or larger than 2) and a planetary gear Pk which is engaged with the internal gear Ik and revolves in a circumferential direction of the internal gear, the planetary gear Pk of each planetary gear mechanism is composed of a spur gear in the form of an external gear, the planetary gears Pk of the planetary gear mechanisms share a central axis or have central axes integrally connected to integrally rotate on a common rotation central axis line or are integrated with each other to integrally rotate on the common rotation central axis line in order to configure the entire planetary gear device as a two-stage gear mechanism, the planetary gear device is configured such that the number of teeth zp1 of a first planetary gear constituting the first planetary gear

Abstract: A motor producing a rectilinear drive force can be simultaneously provided with a small size and a lightweight, high accuracy and a large drive force. In a spiral linear motor 1, a rotator 3 and stator 2 are both constituted having a spiral shape and, by joining together both spiral-shaped parts, a drive force is produced in the axial direction during rotation in a spiral shape. By affording the spiral linear motor a spiral shape, a large drive force can be obtained similarly to that of a reduction gear and a large drive force can be obtained by utilizing a large area that lies opposite in the axial direction of the rotator and stator.

Abstract: A motor producing a rectilinear drive force can be simultaneously provided with a small size and a lightweight, high accuracy and a large drive force. In a spiral linear motor 1, a rotator 3 and stator 2 are both constituted having a spiral shape and, by joining together both spiral-shaped parts, a drive force is produced in the axial direction during rotation in a spiral shape. By affording the spiral linear motor a spiral shape, a large drive force can be obtained similarly to that of a reduction gear and a large drive force can be obtained by utilizing a large area that lies opposite in the axial direction of the rotator and stator.