An application, in particular for motor vehicle closing devices. The basic design of the motor vehicle has an electric motor and an actuating element which is acted upon by the electric motor directly or indirectly via a powertrain. The powertrain is provided with at least one Evoloid toothing. According to the invention, a drive shaft of the electric motor is equipped with an Evoloid pinion which meshes with an Evoloid output gear at the input of the powertrain, thereby directly producing the Evoloid toothing.

An application, in particular for motor vehicle closing devices. The basic design of the motor vehicle has an electric motor and an actuating element which is acted upon by the electric motor directly or indirectly via a powertrain. The powertrain is provided with at least one Evoloid toothing. According to the invention, a drive shaft of the electric motor is equipped with an Evoloid pinion which meshes with an Evoloid output gear at the input of the powertrain, thereby directly producing the Evoloid toothing.

A gear is provided that has excellent continuous moldability for practical use, and both high slidability and high durability. The provided gear is a molded resin constructed of a resin composition comprising a thermoplastic resin (A) and cellulose nanofibers (B) with an average fiber diameter of 1000 nm or smaller, and having a number average molecular weight of the thermoplastic resin (A) in the range of 10,000 to 150,000, wherein a sliding surface of the gear with another gear teeth has an arithmetic mean surface roughness Sa of 3.0 μm or lower.

A gear is provided that has excellent continuous moldability for practical use, and both high slidability and high durability. The provided gear is a molded resin constructed of a resin composition comprising a thermoplastic resin (A) and cellulose nanofibers (B) with an average fiber diameter of 1000 nm or smaller, and having a number average molecular weight of the thermoplastic resin (A) in the range of 10,000 to 150,000, wherein a sliding surface of the gear with another gear teeth has an arithmetic mean surface roughness Sa of 3.0 μm or lower.

Plural ejector pins are made to project before a molten resin containing reinforcing fibers is injected into an inside of a cavity through pin point gates in a web forming portion in the inside of the cavity and at positions outside the pin point gates in a radial direction. The ejector pins are retracted from the inside of the cavity after a flow of the molten resin containing reinforcing fibers injected into the inside of the cavity through the pin point gates impinges on the ejector pins and is divided and before a tooth portion forming portion in the inside of the cavity is filled with the molten resin containing reinforcing fibers. Accordingly, weld lines which extend along the radial direction are formed at positions outside the ejector pins in the radial direction, and the molten resin is filled in portions formed after the ejector pins are retracted.

Plural ejector pins are made to project before a molten resin containing reinforcing fibers is injected into an inside of a cavity through pin point gates in a web forming portion in the inside of the cavity and at positions outside the pin point gates in a radial direction. The ejector pins are retracted from the inside of the cavity after a flow of the molten resin containing reinforcing fibers injected into the inside of the cavity through the pin point gates impinges on the ejector pins and is divided and before a tooth portion forming portion in the inside of the cavity is filled with the molten resin containing reinforcing fibers. Accordingly, weld lines which extend along the radial direction are formed at positions outside the ejector pins in the radial direction, and the molten resin is filled in portions formed after the ejector pins are retracted.

A gear includes a sintered body, in which Fe is contained as a principal component, Ni is contained in a proportion of 2 mass % or more and 20 mass % or less, Si is contained in a proportion of 0.3 mass % or more and 5.0 mass % or less, C is contained in a proportion of 0.005 mass % or more and 0.3 mass % or less, and one element selected from the group consisting of Ti, V, Y, Zr, Nb, Hf, and Ta is defined as a first element, that is contained in a proportion of 0.01 mass % or more and 0.7 mass % or less.

A method to form a gear for motor vehicles includes one or more of the following: placing a blank between a first tool member and a second tool member, each of the first tool member and the second tool member having a set of teeth; and moving the first tool member and the second tool member towards the blank while rotating the first tool member and the second tool member to form a gear with a set of teeth from the blank. Each tooth of the set of teeth has a topography that varies tooth-to-tooth.

A gear device includes a first gear, and a second gear meshing with the first gear. At least the first gear is made of a resin. The gear device further includes a connection member connected to an external member, a path member disposed in a path leading to the first gear and the connection member, and other members that are members other than the first gear, the second gear, the connection member, and the path member, and are made of a resin. The first gear, the connection member, and the path member are made of a resin having a higher thermal conductivity than a thermal conductivity of the other members.

A gear device includes a first gear, and a second gear meshing with the first gear. At least the first gear is made of a resin. The gear device further includes a connection member connected to an external member, a path member disposed in a path leading to the first gear and the connection member, and other members that are members other than the first gear, the second gear, the connection member, and the path member, and are made of a resin. The first gear, the connection member, and the path member are made of a resin having a higher thermal conductivity than a thermal conductivity of the other members.