Patent US3570427A successfully refreshed from Google Patents.
US3570427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Top feed means for sewing machines
Assignee: GM Pfaff AG
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Filing: 1969-07-02
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Granted: 1971-03-16
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Expires: 1989-07-02
Abstract
Abstract Top feed means for sewing machines having a presser foot and a spring biased top feed foot linked to a feeding and raising drive and connected with a carrier on the presser bar, which top feed foot is connected to a link connected with the feeding mechanism and joined with the carrier by a lever connected with the raising elements, which is pivotally supported by the carrier and reaches below a roller element that is arranged on the top feed foot.
Inventors
- 👤 Herbert Wenz
- 👤 Heinrich Berg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:44
CPC Classifications
D; D05; D05B; D05B27/00; D05B27/02; D05B27/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
140 words
Top feed means for sewing machine of the type having a housing, a drive shaft in said housing, a presser foot bar movable axially in said housing and supporting a presser foot a first spring disposed in said housing biasing said presser foot bar, a carrier secured to said presser foot bar, a top feed foot and a link connecting said top feed foot with said carrier, a second spring for biasing said top feed foot downwardly, means operably connecting said top feed foot with said drive shaft for imparting feed movements thereto, a lever pivotally connected to said carrier, and means connecting said lever to said drive shaft for imparting rocking movements to said lever, and a roller rotatably supported on said top feed foot, said lever extending below said roller for engaging said roller while executing rocking movements.
Claim 2
Dependent Claim
140 words
Top feed means for sewing machine of the type having a housing, a drive shaft in said housing, a presser foot bar movable axially in said housing and supporting a presser foot a first spring disposed in said housing biasing said presser foot bar, a carrier secured to said presser foot bar, a top feed foot and a link connecting said top feed foot with said carrier, a second spring for biasing said top feed foot downwardly, means operably connecting said top feed foot with said drive shaft for imparting feed movements thereto, a lever pivotally connected to said carrier, and means connecting said lever to said drive shaft for imparting rocking movements to said lever, and a roller rotatably supported on said top feed foot, said lever extending below said roller for engaging said roller while executing rocking movements.
Claim 3
Dependent Claim
50 words
Top feed means in accordance with claim 1, wherein said second biasing spring and a guiding bolt are in said presser foot bar, an abutment on said top feed foot and a ball intermediate said abutment and said guiding bolt, and said carrier defining a conical surface around said ball.
Claim 4
Dependent Claim
56 words
Top feed means in accordance with claim 1 including means operative to apply the pressure of said second spring to said top feed foot, said means comprising a pressure surface on said top feed foot, a ball in engagement with said pressure surface, and an abutment surface proximate said carrier limiting lateral movement of said ball.
Claim 5
Dependent Claim
18 words
Top feed means in accordance with claim 3, where said second spring is arranged inside said presser bar.
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) | 1974-03-15 | 1974-09-14 | 1975-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-15 | 1978-09-14 | 1979-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-15 | 1982-09-14 | 1983-03-16 | $7700.00 | Window Closed / Lapsed |