A gear manufacturing method, the gear including an annular gear portion including teeth on an outer periphery, an annular support portion provided on an inner peripheral surface of the gear portion and supporting the gear portion, and a core portion provided inside the support portion, the method includes: a support portion molding step of molding the support portion by disposing the gear portion and the core portion in an annular mold and filling a resin between the gear portion and the core portion; and a support portion cooling step of cooling the support portion molded in the support portion molding step, a radial gap between the teeth of the gear portion and the mold before the support portion molding step is set to be smaller than a radial shrinkage amount of the support portion in the support portion cooling step.

Carbodiimide is added to a molten polyamide resin so as to provide resin pellets. The percentage of residual unreacted carbodiimide to each resin pellet is 0.03% to 0.33% by mass. Manufacturing molded articles using the resin pellets achieves both of an improvement in mechanical strength and an increase in wear resistance, and reduces property variations among the molded articles.

The invention relates to a method for producing a gear, said method including a step (a) during which a supporting core is made from a first polymer material, said supporting core comprising a hub, with a director axis (XX), as well as a flange which extends radially from said hub to a peripheral flanged edge, said method then involves a coating step (b) which comprises producing a permanent coating layer, made of a second polymer material, by overmolding on the supporting core, including integrally both a front layer which covers the upper surface of the flange, and a side layer which extends said front layer axially by covering the outer radial surface of the flanged edge, such that said side layer forms a rim, the teeth of the gear being made in the radial body of said rim.

Provided is an injection molding apparatus for a worm wheel, in which the worm wheel is not only integrally manufactured by an injection mold method, but a gear teeth structure of a gear forming unit is also manufactured as an injection mold without a hobbing operation, and the structure of the injection molding apparatus is also improved so that worm wheel products can be easily taken out from the injection mold. The injection molding apparatus includes: a boss injection mold; a product injection mold having a movable side core, a fixed side core, and a worm gear tooth-shaped core; and a take-out unit for taking out a worm wheel product formed with a worm gear by the product injection mold, wherein the take-out unit includes: a plurality of take-out pins; a take-out plate; and a guide unit guiding rotation of the worm gear tooth-shaped core.

A multi-stage helical gear manufacturing apparatus includes a first mold member, a second mold member, a large gear rotation core, a sleeve pin, a small gear rotation insert, and an insert pin. The second mold member moves the insert pin and the small gear rotation insert after the insert pin is caused to retreat in relation to the small gear rotation insert at the time of mold opening. The first mold member prohibits rotation of the large gear rotation core at the time of mold clamping, permits rotation of the large gear rotation core when the insert pin and the small gear rotation insert of the second mold member are moved at the time of mold opening, and causes the sleeve pin to advance toward the second mold member in relation to the plastic after the insert pin and the small gear rotation insert are separated from the plastic.

A gear housing for an epicyclic gear set, the gear housing including a hollow wheel having internal teething and a first front end with a first front-side joining surface; a housing cover having a second front end with a second front-side joining surface for longitudinally axially covering the hollow wheel; and a bonded connection for connecting the first front end to the second front end through the mating of the first and second front-side joining surfaces, at which the hollow wheel and the housing cover are connected to each other by a bonded connection, in particular, by heated tool welding, infrared welding, ultrasonic welding, or rotary friction welding.

A method for producing a ring gear for a planetary gear train, wherein a continuous profile is produced by an extrusion process and the continuous profile is subsequently cut to a predetermined cutting length in order to form a ring gear body.

Provided herein is an apparatus of manufacturing a molding material that can significantly reduce the frequency of replacement of a bottom member without increasing the drainage time longer. A bottom member (39) is constituted of two layers of wire meshes including an annular dutch-woven wire mesh (39A) made of stainless steel and an annular plain-woven wire mesh made of stainless steel. The two layers of wire meshes are secured to each other by sintering. A support plate (40) made of stainless steel is disposed between the bottom member (39) and a lower hollow compression mold (2). The support plate (40) has a plurality of through holes (41) formed therein, and is configured to support the bottom member (39).

A gear comprising: a hub defining an outer surface, the hub comprising a ceramic material; and a first ring defining an inner surface and an outer surface, the inner surface of the first ring being coupled to the outer surface of the hub via a bond, the outer surface of the first ring defining a plurality of gear teeth, and the first ring comprising a metallic material.

Provided herein is a molding material that attains little fluctuation in amount of short fibers and powdery resin among individual products and that allows continuous production without damaging a die. In the step of pouring, slurry is poured onto a slurry diffusion member 7 from above the slurry diffusion member 7. The slurry diffusion member 7 extends in an upward direction, and is shaped such that the area of a transverse section taken along a direction orthogonal to the upward direction becomes smaller as the slurry diffusion member 7 extends in the upward direction. In the step of cleaning, a dispersion medium that is the same as the dispersion medium used in the step of pouring or water is poured onto the slurry diffusion member 7 from above the slurry diffusion member 7 to cause the short fibers and the powdery resin adhering to a slurry diffusion portion 71 of the slurry diffusion member 7 to fall down. After that, the dispersion medium is discharged from a cylindrical die 3 to accumulate the short fibers and the powdery resin in the cylindrical die 3 to obtain an aggregate 38 of the short fibers and the powdery resin. Then, the aggregate 38 is compressed.