US3860844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low friction miniature gear drive for transmitting small forces
Assignee: SSIH Management Services SA
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Filing: 1973-11-06
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Granted: 1975-01-14
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Expires: 1993-11-06
Abstract
Abstract A miniature gear drive, such as that used in clockworks, is disposed in one chamber of a housing having two chambers interconnected by a capillary channel. The chamber containing the gears is sealed except for the channel, and the entire assembly immersed in a lubricant liquid within a vacuum chamber. The vacuum chamber is evacuated and then the vacuum removed so that the lubricant completely fills both chambers of the housing. The assembly is removed from the vacuum chamber and heated whereby the liquid expands and a portion of the liquid escapes through an opening in the second housing chamber. The assembly is then cooled so that an air bubble is formed in the second housing chamber, and the second chamber is then sealed. The input power to the gear drive, and the output power therefrom are obtained by magnetic coupling through the housing. The air bubble permits expansion of the liquid within the housing due to temperature changes, but the capillary channel prevents this bubble from reaching the chamber containing the gear drive hence the gears are always completely immersed in the liquid.
Inventors
- 👤 Max Hetzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:23
CPC Classifications
G; G04; G04D; G04D3/00; G04D3/0002; G04D3/0061; G04B; G04B11/00; G04B11/001; G04B11/003; G04B11/005; G04B37/00; G04B37/02; G04D3/0017; Y; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2186
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
103 words
A low friction miniature gear drive for transmitting small forces said gear drive comprising: a housing having a gear train chamber; a gear train disposed within said chamber; a liquid within said chamber completely immersing said gear train; means closing said chamber; magnetic means for transmitting power to and from said gear train through the wall of said housing; an expansion chamber in said housing; and, a channel connecting said expansion chamber to said gear train chamber; said liquid completely filling said gear train chamber and filling said expansion chamber except for a small air bubble thereiN; and means closing said expansion chamber.
Claim 2
Dependent Claim
103 words
A low friction miniature gear drive for transmitting small forces said gear drive comprising: a housing having a gear train chamber; a gear train disposed within said chamber; a liquid within said chamber completely immersing said gear train; means closing said chamber; magnetic means for transmitting power to and from said gear train through the wall of said housing; an expansion chamber in said housing; and, a channel connecting said expansion chamber to said gear train chamber; said liquid completely filling said gear train chamber and filling said expansion chamber except for a small air bubble thereiN; and means closing said expansion chamber.
Claim 3
Dependent Claim
31 words
A gear drive as claimed in claim 1 wherein said channel is a capillary channel which prevents said air bubble from passing from said expansion chamber into said gear train chamber.
Claim 4
Dependent Claim
31 words
A gear drive as claimed in claim 1 wherein the means closing said chambers comprise covers mounted over openings in said housing by a two-component adhesive to hermetically seal said chambers.
Claim 5
Dependent Claim
26 words
A gear drive as claimed in claim 3 wherein the cover for said gear train chamber includes means for pivotally supporting the gears of said train.
Claim 6
Dependent Claim
168 words
A low friction miniature gear drive for transmitting small forces said gear drive comprising: a housing having a gear train chamber; a gear train disposed within said chamber; a liquid within said chamber completely immersing said gear train; means closing said chamber; and, magnetic means for transmitting power to and from said gear train through the wall of said housing; said means for transmitting power to and from said gear train comprising: first and second pairs each including first and second magnetic coupling discs; the first disc of said first pair being mounted on the input shaft of said gear train and the first disc of said second pair being mounted on the output shaft of said gear train; means mounting the second disc of said first pair for rotational movement outside of said housing adjacent the first disc of said first pair; and, means mounting the second disc of said second pair for rotational movement outside of said housing adjacent the first disc of said second pair.
Claim 7
Dependent Claim
168 words
A low friction miniature gear drive for transmitting small forces said gear drive comprising: a housing having a gear train chamber; a gear train disposed within said chamber; a liquid within said chamber completely immersing said gear train; means closing said chamber; and, magnetic means for transmitting power to and from said gear train through the wall of said housing; said means for transmitting power to and from said gear train comprising: first and second pairs each including first and second magnetic coupling discs; the first disc of said first pair being mounted on the input shaft of said gear train and the first disc of said second pair being mounted on the output shaft of said gear train; means mounting the second disc of said first pair for rotational movement outside of said housing adjacent the first disc of said first pair; and, means mounting the second disc of said second pair for rotational movement outside of said housing adjacent the first disc of said second pair.
Claim 8
Dependent Claim
26 words
A gear drive as claimed in claim 5 wherein the first and second discs of one of said pairs are mounted for rotation about coaxial axes.
Claim 9
Dependent Claim
43 words
A gear drive as claimed in claim 5 wherein the first and second discs of one of said pairs are mounted for rotation about parallel axes offset from each other to bring the peripheries of the discs of the pair into close proximity.
Claim 10
Dependent Claim
36 words
A gear drive as claimed in claim 5 wherein each magnetic coupling disc comprises a disc having a plurality of magnets disposed around its periphery, each magnet being opposite in polarity to the magnets nearest it.
Claim 11
Dependent Claim
29 words
A gear drive as claimed in claim 5 wherein each magnetic coupling disc comprises a disc having a ring of magnetic material of alternating polarity extending around its periphery.
Claim 12
Dependent Claim
28 words
A gear drive as claimed in claim 8 wherein on disc of at one of said pairs has more magnets thereon than the other disc of the pairs.
Claim 13
Dependent Claim
31 words
A gear drive as claimed in claim 9 wherein the ring on one disc of one of said pairs exhibits more alternations in polarity than the other disc of the pair.
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) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |