Internally-toothed member, and method and apparatus for molding same
US6508094B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2000 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Jun 30, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21H7/187
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The present invention provides an internally-toothed member of reduced size and enhanced quality, durability and productivity in manufacture. This internally-toothed member has a first cylinder portion and a second cylinder portion which is larger in diameter than the first cylinder portion. First and second internal teeth are formed to protrude radially inwardly from inner peripheral surfaces of the first and second cylinder portions respectively. Because a meshing portion can be formed as second internal teeth protruding from an inner periphery of the second cylinder portion, the diameter of the internally-toothed member is relatively small. Because the area between the second internal teeth and a concave portion and the concave portion itself do not decrease in thickness during formation of the second internal teeth, it is possible to prevent cracking and to thereby enhance durability of the internally-toothed member. Further, because there is no sagging of the inner peripheral surface of the meshing portion, the quality of the internally-toothed member is further enhanced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.