Title:
STEP DRILL WITH A SPIRAL-FORM GROOVE
Document Type and Number:
WIPO Patent Application WO/2008/092386
Kind Code:
A1
Abstract:
A step drill includes a body with an integrally formed handle, in which a spiral-form groove
extends from the end to the front of the body, and the groove bottom is a paraboloidal structure.
The combination surface of adjacent diameter is concave arc surface, or the combination
surface of adjacent diameter is inclined surface, and the angle between the diameter
of one side and the inclined surface is 43-47 degree.
Inventors:
ZHANG, Qi (Room 406, Wang Xiang Xin Cun 14 DongNo. 41, Wenchang Mid Road,Guangling District,Yangzhou, Jiangsu 1, 225001, CN)
Application Number:
CN2008/000221
Publication Date:
August 07, 2008
Filing Date:
January 29, 2008
Export Citation:
Assignee:
ZHANG, Qi (Room 406, Wang Xiang Xin Cun 14 DongNo. 41, Wenchang Mid Road,Guangling District,Yangzhou, Jiangsu 1, 225001, CN)
International Classes:
B23B51/00; B23B51/12
Attorney, Agent or Firm:
NANJING ZHONGLIAN PATENT AGENCY CO., LTD. (Jiangsu Jixie Building, No.49 Zhongshan North Road,Nanjing, Jiangsu 8, 210008, CN)
Download PDF:
Previous Patent: SYSTEMS AND METHODS FOR ONLINE GAMES
Next Patent: A METHOD AND APPARATUS FOR TRANSMITTING SIGNAL AND A COMMUNICATION SYSTEM
Next Patent: A METHOD AND APPARATUS FOR TRANSMITTING SIGNAL AND A COMMUNICATION SYSTEM