Rack bar and rack bar teeth forming die
AssigneeNeturen Co., Ltd.
InventorsMakoto Nomura, Takashi Yamawaki, Ryosuke Suzuki
Life of this patent
Estimating the term…
Abstract
A rack bar includes a shaft portion and a rack toothed portion provided on the shaft portion. The rack toothed portion includes a plurality of rack teeth provided side by side in an axial direction of the shaft portion to mesh with a pinion gear. Each of the rack teeth includes a tooth tip portion, a contact face arranged obliquely relative to the axial direction and configured to contact the pinion gear, and a rounded corner portion between the tooth tip portion and the contact face. A first radius defining a central area of the rounded corner portion with respect to a tooth width direction is larger than a second radius defining another area of the rounded corner portion other than the central area.
Claims2
A teeth forming die configured to form rack teeth of a rack bar to be meshed with a pinion gear, the teeth forming die comprising a securing portion configured to be secured to an outside clamp case, and a rack teeth transfer portion provided on the securing portion,
- wherein the rack teeth transfer portion comprises a plurality of rack tooth transfer portions provided side by side in a line,
- wherein each of the rack tooth transfer portions is configured to transfer a profile of each rack tooth, each of the rack tooth transfer portions comprising a tooth bottom transfer portion configured to transfer a profile of a tooth bottom portion of the rack tooth, a tooth tip transfer portion configured to transfer a profile of a tooth tip portion of the rack tooth, a contact face transfer portion arranged obliquely relative to a direction of the line in which the rack tooth transfer portions are provided side by side and configured to transfer a profile of a contact face of the rack tooth to be brought into contact with the pinion gear, and a rounded corner portion between the tooth tip transfer portion and the contact face transfer portion,
- wherein a first radius defining a central area of the rounded corner portion with respect to a tooth width direction is larger than a second radius defining another area of the rounded corner portion other than the central area.
Dependencies are inferred from the claim text.