US4366871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor-driven screwdriver
Assignee: Robert Bosch GmbH
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Filing: 1981-01-21
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Granted: 1983-01-04
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Expires: 2001-01-21
Abstract
Abstract A screwdriver comprises a planetary gear carrier rotatably carrying a plurality of circumferentially displaced planet gears meshing with a pinion driven by the motor of the screwdriver and with teeth provided on the inner surface of a coupling element in form of a hollow cylinder surrounding the carrier. The coupling element is also provided at one end with coupling teeth axially displaced from the first-mentioned teeth. The coupling element is movable by a fluid-operated piston from a first position to which it is biased by springs, in which the coupling teeth thereon are in mesh with corresponding coupling teeth on the carrier to rotate with the same speed as the latter, to a second position in which the coupling teeth on the coupling element are in mesh with stationary teeth on a housing surrounding the carrier and the coupling element to hold the latter against rotation.
Inventors
- 👤 Herbert Dieterle
- 👤 Alfred Hettich
- 👤 Karl Roll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:44
CPC Classifications
B; B25; B25B; B25B21/00; B25B21/008
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
115 words
A screwdriver comprising a drive motor having a drive shaft and a work shaft spaced from and coaxial with said drive shaft; planetary gear means between said drive shaft and said work shaft for driving the latter at different speeds of rotation during rotation of said drive shaft at a constant speed, said planetary gear means comprising drive elements directly connected with said drive shaft for rotation therewith and a planetary gearing element constructed as a movable coupling element movable between a first position rotating with said drive elements and a second position in which it is prevented from rotation; and means connected to said coupling element for moving the same between said positions thereof.
Claim 2
Dependent Claim
115 words
A screwdriver comprising a drive motor having a drive shaft and a work shaft spaced from and coaxial with said drive shaft; planetary gear means between said drive shaft and said work shaft for driving the latter at different speeds of rotation during rotation of said drive shaft at a constant speed, said planetary gear means comprising drive elements directly connected with said drive shaft for rotation therewith and a planetary gearing element constructed as a movable coupling element movable between a first position rotating with said drive elements and a second position in which it is prevented from rotation; and means connected to said coupling element for moving the same between said positions thereof.
Claim 3
Dependent Claim
35 words
A screwdriver as defined in claim 1, wherein said planetary gearing element constructed as a movable coupling element is in the form of a hollow cylinder surrounding said drive elements of said planetary gear means.
Claim 4
Dependent Claim
40 words
A screwdriver as defined in claim 1, wherein said coupling element is axially movable between said positions thereof, and wherein said means for moving said coupling element between said positions thereof comprises a fluid-operated piston connected to said coupling element.
Claim 5
Dependent Claim
33 words
A screwdriver as defined in claim 3, and including spring means biasing said piston and said coupling element connected thereto to a position in which said coupling element is in said second position.
Claim 6
Dependent Claim
137 words
A screwdriver as defined in claim 3, wherein said hollow cylinder constituting said coupling element is provided at the inner surface thereof with gear teeth and coupling teeth axially displaced from said gear teeth, and wherein said drive elements directly connected with said drive shaft comprise an intermediate shaft coupling at one end with said drive shaft and forming at the other end a pinion, a planet gear carrier provided at one end thereof with coupling teeth, a plurality of circumferentially displaced planet gears rotatably carried by said planet gear carrier, meshing with said pinion and also meshing with said gear teeth of said coupling element, said coupling teeth of said coupling element and said coupling teeth on said planetary gear carrier being arranged to mesh with each other in said first position of said coupling element.
Claim 7
Dependent Claim
52 words
A screwdriver as defined in claim 5, and including a housing surrounding said planetary gear means and provided with stationary coupling means arranged for meshing with said coupling teeth on said hollow cylinder constituting said coupling element when the latter is in said second position, thereby preventing said coupling element from rotation.
Claim 8
Dependent Claim
18 words
A screwdriver as defined in claim 6, wherein said planetary gear means forms part of an independent unit.
Claim 9
Dependent Claim
26 words
A screwdriver as defined in claim 7, wherein said independent unit further includes said housing and a head member mounted on one end of said housing.
Claim 10
Dependent Claim
44 words
A screwdriver as defined in claim 8, and including a work shaft housing turnably mounting said work shaft, said independent unit being threadingly connected at said one end with said drive motor and at the other end threadingly connected with said work shaft housing.
Claim 11
Dependent Claim
64 words
A screwdriver as defined in claim 8, wherein said head member is provided with a plurality of circumferentially spaced stepped bores parallel to said drive shaft and including a plurality of bolts slidably guided in said bores and connected at inner ends to said piston, and a coil compression spring about each of said bolts for biasing the respective bolt in axially outward direction.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-03 | 1986-07-05 | 1987-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-03 | 1990-07-05 | 1991-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-03 | 1994-07-05 | 1995-01-04 | $7700.00 | Window Closed / Lapsed |