External circulation ball screw
AssigneeHiwin Technologies Corp.
InventorsYi-Lung SUN, Chia-Ming YANG
Life of this patent
Estimating the term…
Abstract
An external circulation ball screw consisting of a screw shaft, a screw nut, a cover, two reflow members and multiple rolling members is disclosed. The screw nut defines a mounting groove on the outer perimeter and two return holes in the mounting groove. A first half-return channel on a first step in the mounting groove of the screw nut and a second half-return channel in a second step inside the cover constitute a return channel. Alternatively, a third step can be formed in the cover, or the screw nut can be configured to provide a mounting groove and a third step with return holes in the mounting groove. Thus, same size of reflow members can be used with different lengths of return channels.
Claims8
An external circulation ball screw, comprising:
- a screw shaft comprising an external thread groove around the periphery thereof;
- a screw nut threaded onto said screw shaft and axially movable along said screw shaft, said screw nut comprising an internal thread groove that defines with said external thread groove of said screw shaft a load path, a mounting groove located on an opposing outer perimeter thereof, two opposite return holes respectively disposed in communication between said mounting groove and said load path, a first step located in said mounting groove between said two return holes and a first half-return channel formed on said first step;
- a cover mounted on said screw nut to cover said mounting groove, said cover comprising a second step located at an inner side thereof and a second half-return channel formed on said second step, said second half-return channel and said first half-return channel constituting a return channel;
- two reflow members each comprising a passage therein, a first end located at one end of said passage and a second end located at an opposite end of said passage, the said first end of each said reflow member being inserted into one respective said return hole of said screw nut to keep said passage in communication with said load path, the said second ends of said two reflow members being respectively disposed at two opposite sides relative to said return channel to keep said passages in communication with said return channel, said load path, said return channel and the said passages of said two reflow members creating a reflow path;
- and
- a plurality of rolling members movably mounted in said reflow path.
An external circulation ball screw, comprising:
- a screw shaft comprising an external thread groove around the periphery thereof;
- a screw nut threaded onto said screw shaft and axially movable along said screw shaft, said screw nut comprising an internal thread groove that defines with said external thread groove of said screw shaft a load path, a mounting groove located on an opposing outer perimeter thereof, two opposite return holes respectively disposed in communication between said mounting groove and said load path;
- a cover mounted on said screw nut to cover said mounting groove, said cover or said screw nut comprising a third step located at an inner side thereof between said two return holes and a return channel located on said third step;
- two reflow members each comprising a passage therein, a first end located at one end of said passage and a second end located at an opposite end of said passage, the said first end of each said reflow member being inserted into one respective said return hole of said screw nut to keep said passage in communication with said load path, the said second ends of said two reflow members being respectively disposed at two opposite sides relative to said return channel to keep said passages in communication with said return channel, said load path, said return channel and the said passages of said two reflow members creating a reflow path;
- and
- a plurality of rolling members movably mounted in said reflow path.
Dependencies are inferred from the claim text.