The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 1989
Filed:
Jan. 22, 1988
Takeshi Obata, Narashino, JP;
Hideaki Kobayashi, Sakura, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A ring spinning machine has a direct drive spindle rotatably supported by an upper bearing in a bolster and connected to a rotor of a spindle motor having an upper structure including upper coil end of a stator thereof. A ring is movable up and down along the spindle to guide a yarn to be wound on a bobbin carried by the spindle. The inside diameter of the ring is determined in relation to the size of the upper structure of the spindle motor such that the upper structure can be received at least partially in the ring when the ring is moved to the lower end of its vertical stroke. The length of the unsupported portion of the spindle is reduced to increase the critical or resonance speed of the spindle, thus enabling the spindle to operate at an increased speed.