US 6,282,970 B1 · Locking drive nut for screw drive systems

Abstract

A screw drive mechanism connectable to at least one of a first machine portion and a second machine portion for moving the second machine portion relative to the first machine portion from a first position to a second position. The mechanism has a base for attachment to one of the first and the second machine portions and a motor attached to the base. It includes a drive screw having a rotary motion connection to the motor to be rotated thereby and a drive nut having an internally threaded bore engaged with the drive screw to receive a drive force from the drive screw. A drive nut connection is engaged with the drive nut for conveying the drive force to one of the first and the second machine portions. An anti-rotation member is attached to the drive nut connection, the anti-rotation member engaging the drive nut to prevent rotation thereof. The mechanism also includes an activation member attached to the base, the activation member contacting a disengaging surface portion of the anti-rotation member when such one of the first and the second machine portions is moved to the second position to place the anti-rotation member in a position disengaged from the drive nut so that the drive nut may rotate. A drive nut rotating device is attached to the base, the drive nut rotating device rotating the drive nut to a locking position when such one of the first and the second machine portions is moved to the second position.

Claims20

Dependent claims

A screw drive mechanism connectable to a first machine portion and to a second machine portion for moving such second machine portion relative to such first machine portion from a first position to a second position, said screw drive mechanism comprising:

(a) a base member engageable with at least one of such first machine portion and such second machine portion;
(b) a motor attached to said base member;
(c) a drive screw having a rotary motion connection to said motor to be rotated thereby;
(d) a drive nut having an internally threaded bore engaged with said drive screw to receive a drive force therefrom;
(e) a drive nut connection engaged with said drive nut and engageable with such second machine portion for conveying said drive force to an opposed one of such first machine portion and such second machine portion;
(f) an anti-rotation member attached to said drive nut connection, said anti-rotation member engaging said drive nut to prevent rotation of said drive nut;
(g) an activation member attached to said base, said activation member contacting a disengaging surface portion of said anti-rotation member when such opposed one of such first machine portion and such second machine portion is moved to such second position to place said anti-rotation member in a position that is disengaged from said drive nut so that said drive nut may rotate;
and
(h) a drive nut rotating device attached to said base member, said drive nut rotating device including a roller having an axis substantially perpendicular to said drive screw, said drive nut including a track for engaging said roller to rotate said drive nut to a locking position when such opposed one of such first machine portion and such second machine portion is moved to such second position.

6 more elements

A screw drive mechanism for a door of a passenger transit type vehicle for moving such door from an open position to a closed position, said screw drive mechanism comprising:

(a) a base member engageable with such passenger transit type vehicle;
(b) a motor attached to said base member;
(c) a drive screw having a rotary motion connection to said motor to be rotated thereby;
(d) a drive nut having an internally threaded bore engaged with said drive screw to receive a drive force therefrom;
(e) a drive nut connection engaged with said drive nut and engageable with such door to convey said drive force to such door;
(f) an anti-rotation member attached to said drive nut connection, said anti-rotation member engaging said drive nut to prevent rotation of said drive nut;
(g) an activation member attached to said base member, said activation member contacting a disengaging surface portion of said anti-rotation member when such door is moved to such closed position to place said anti-rotation member in a position disengaged from said drive nut so that said drive nut may rotate;
and
(h) a drive nut rotating device attached to said base member, said drive nut rotating device including a roller having an axis substantially perpendicular to said drive screw, said drive nut including a track for engaging said roller to rotate said drive nut to a locking position when such door is moved to such closed position.

6 more elements

Dependencies are inferred from the claim text.

Locking drive nut for screw drive systems

Life of this patent

Locking drive nut for screw drive systems

Life of this patent

Abstract

Claims20