US4226137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screw and nut mechanism
Assignee: ZF International UK Ltd
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Filing: 1978-07-20
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Granted: 1980-10-07
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Expires: 1998-07-20
Abstract
Abstract A recirculating ball screw and nut mechanism wherein the screw of the mechanism comprises a shaft having an external helical groove, and the nut comprises a sleeve encircling the shaft and having an internal helical groove defining with the groove a helical working track in which run balls effective co-operation between the nut and the screw. The balls move from one end to the other of the working track during relative rotation of the nut and screw and are returned from said other end to said one end of the working track by way of a ball return path. The return path includes a groove extending around the inner wall of the sleeve and/or the outer surface of the shaft coaxial with the working track and between the convolutions of the working track without crossing the working track. The return path includes generally U-shaped regions at each for respectively diverting balls from and returning balls to the working track.
Inventors
- 👤 Roy T. Sharp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:02
CPC Classifications
F; F16; F16H; F16H25/00; F16H25/18; F16H25/20; F16H25/22; F16H25/2204; F16H25/2214; F16H25/2223; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19642; Y10T74/19698; Y10T74/19702; Y10T74/19744; Y10T74/19749; Y10T74/19767
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
177 words
A recirculating ball screw and nut mechanism comprising a screw which includes a shaft having an external helical groove, a nut including a sleeve encircling said shaft, said sleeve having an internal helical groove defining with said external groove of the shaft a helical working track and balls running in said track for effecting co-operation between the nut and the screw, said balls moving from one end to the other end of said working track during relative rotation of the nut and screw and means wholly within said sleeve defining a ball return path for returning balls from said other end to said one end of the working track, said ball return path including a groove extending around an inner wall of the sleeve coaxial with the working track and between convolutions of the working track without crossing the working track, said groove having a depth greater than the diameter of the balls and the return path including a generally U-shaped region at each end for respectively diverting balls from and returning balls to the working track.
Claim 2
Dependent Claim
177 words
A recirculating ball screw and nut mechanism comprising a screw which includes a shaft having an external helical groove, a nut including a sleeve encircling said shaft, said sleeve having an internal helical groove defining with said external groove of the shaft a helical working track and balls running in said track for effecting co-operation between the nut and the screw, said balls moving from one end to the other end of said working track during relative rotation of the nut and screw and means wholly within said sleeve defining a ball return path for returning balls from said other end to said one end of the working track, said ball return path including a groove extending around an inner wall of the sleeve coaxial with the working track and between convolutions of the working track without crossing the working track, said groove having a depth greater than the diameter of the balls and the return path including a generally U-shaped region at each end for respectively diverting balls from and returning balls to the working track.
Claim 3
Dependent Claim
17 words
A mechanism as claimed in claim 1 wherein said groove extends helically parallel to the working track.
Claim 4
Dependent Claim
21 words
A mechanism as claimed in claim 1 wherein said groove extends in a direction other than parallel to the working track.
Claim 5
Dependent Claim
84 words
A mechanism as claimed in claim 3 wherein the angle subtended between the groove and the working track, and the length of the groove are such as to cause the position of the inlet end of the groove to be adjacent the working track convolution into which balls are returned and the return end of the groove to be adjacent the convolution of working track from which balls are diverted, so as to afford U-shaped return path end regions of maximum radius of curvature.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-07 | 1984-04-07 | 1984-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-07 | 1988-04-07 | 1988-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-07 | 1992-04-07 | 1992-10-07 | $7700.00 | Window Closed / Lapsed |