Segmented spring for a ball screw
AssigneesKoyo Bearings North America LLC, Jtekt Corporation
InventorsJustin K. Brubaker, Gento Aramoto
Life of this patent
Estimating the term…
Abstract
A ball screw assembly having a ball nut including a first end, a second end, a central bore, and a ball track defined by the inner surface, a ball screw shaft including an outer surface defining a ball track, the ball screw shaft being disposed in the central bore so that the ball tracks form a ball raceway, a first stopper disposed within the ball raceway, a plurality of main balls forming a ball train, the ball train being disposed in the ball raceway, and a main spring assembly disposed in the ball raceway between a first end of the ball train and the first stopper, wherein a spring constant of the first spring portion is greater than a spring constant of the second spring portion.
Claims19
A ball screw assembly comprising:
- a ball nut including a first end, a second end, an inner surface defining a central bore, and a ball track defined by the inner surface;
- a ball screw shaft including an outer surface defining a ball track, the ball screw shaft being disposed in the central bore so that the ball track of the ball nut and ball track of the ball screw form a ball raceway;
- a first stopper disposed at the first end of the ball nut within the ball raceway;
- a plurality of main balls forming a ball train, the ball train being disposed in the ball raceway;
- and
- a main spring assembly including a first spring portion and a second spring portion, the main spring assembly being disposed in the ball raceway between a first end of the ball train and the first stopper,
- wherein a spring constant of the first spring portion is greater than a spring constant of the second spring portion.
A brake assembly comprising:
- a caliper including an arm portion;
- a piston disposed within the caliper, the piston being axially movable along a longitudinal center axis of the piston;
- a first brake pad affixed to the arm portion of the caliper;
- a second brake pad affixed to an end surface of the piston;
- a brake disc disposed between the first brake pad and the second brake pad;
- and
- a ball screw assembly comprising:
- a ball nut including a first end, a second end, an inner surface defining a central bore, and a ball track defined by the inner surface;
- a ball screw shaft including an outer surface defining a ball track, the ball screw shaft being disposed in the central bore so that the ball track of the ball nut and ball track of the ball screw form a ball raceway;
- a first stopper disposed at the first end of the ball nut within the ball raceway;
- a plurality of main balls forming a ball train, the ball train being disposed in the ball raceway;
- and
- a main spring assembly including a first spring portion and a second spring portion, the main spring assembly being disposed in the ball raceway between a first end of the ball train and the first stopper,
- wherein a spring constant of the first spring portion is greater than a spring constant of the second spring portion.
The brake assembly further comprising an electric motor having an output shaft, wherein the output shaft is operably connected to the ball screw shaft of the ball screw assembly.
Dependencies are inferred from the claim text.