US4494025A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linear drive device with two motors
Assignee: Lars International SA
•
Filing: 1984-04-23
•
Granted: 1985-01-15
•
Expires: 2004-04-23
Abstract
Abstract The linear feed device is suitable for extremely slow feed rates or extremely small feed steps. It works with two motors (M 1 , M 2 ) which drive a nut (16) and a screw spindle (2) via an intermediate drive (12-15; 22-25). The intermediate drives have slightly different transmission ratios, e.g., 1:0.340909 and 1:0.3414634. With a thread pitch of 2 mm of the spindle, this results, with the same direction of rotation of the motors, in about 0.0013 mm advance per revolution of the motor shafts. With the help of step motors, therefore, extremely small advance steps can be achieved.
Inventors
- 👤 Hans Fickler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:32
CPC Classifications
F; F16; F16H; F16H25/00; F16H25/18; F16H25/20; F16H25/2018; F16H2025/2062; F16H2025/2081; F16H2025/2096; F16H25/22; F16H25/2204; Y; Y10; Y10T; Y10T74/00; Y10T74/15; Y10T74/1526; Y10T74/1527; Y10T74/18; Y10T74/18056; Y10T74/18568; Y10T74/18576; Y10T74/18624; Y10T74/1864
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
77 words
A linear drive device with a screw spindle and a nut with two drive motors, characterized by the fact that one motor (M 2 ) drives the screw spindle (2) via a first intermediate drive and the other motor (M 1 ) drives the nut (16) by means of a hollow shaft (1) via a second intermediate drive (13-15) and that the two intermediate drives have a very slight but precisely defined difference in their transmission ratio.
Claim 2
Dependent Claim
77 words
A linear drive device with a screw spindle and a nut with two drive motors, characterized by the fact that one motor (M 2 ) drives the screw spindle (2) via a first intermediate drive and the other motor (M 1 ) drives the nut (16) by means of a hollow shaft (1) via a second intermediate drive (13-15) and that the two intermediate drives have a very slight but precisely defined difference in their transmission ratio.
Claim 3
Dependent Claim
23 words
A drive device according to claim 1, characterized by the fact that the motors (M 1 , M 2 ) are step motors.
Claim 4
Dependent Claim
22 words
A drive device according to claim 1, characterized by the fact that the intermediate drives are play-free toothed belt drives (13-15; 23-25).
Claim 5
Dependent Claim
18 words
A drive device according to claim 1, characterized by the fact that the intermediate drives are gear drives.
Claim 6
Dependent Claim
43 words
A drive device according to claim 1, characterized by the fact that the screw spindle and the hollow shaft are supported axially play-free (12, 22) and that the nut is a ballbearing rotating nut (16) that interacts play-free with the screw spindle (2).
Claim 7
Dependent Claim
100 words
A drive device according to claim 5, with a closed housing, characterized by the fact that the hollow shaft with nut, its axial-radial bearing arrangement and one intermediate drive are accommodated in a first housing part (G 1 ), that the spindle, its axial-radial bearing arrangement and the other intermediate drive are accommodated in a second housing part (G 2 ), and that these housing parts are mounted so as to move relative to each other in the spindle axial direction and that the motors (M 1 , M 2 ) are flange-mounted on the outside of these housing parts.
Claim 8
Dependent Claim
25 words
A drive device according to claim 6, characterized by the fact that the two housing parts are secured against twisting around the spindle's longitudinal axis.
References Cited (Backward Citations)
US3407680A
Cited
US3824420A
Cited
US3855487A
Cited
US4066922A
Cited
US4122377A
Cited
SU664263A1
Cited
US4288168A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-15 | 1988-07-16 | 1989-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-15 | 1992-07-16 | 1993-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-15 | 1996-07-16 | 1997-01-15 | $7700.00 | Window Closed / Lapsed |