Patent US6181271B1 successfully refreshed from Google Patents.
US3889801A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum conveyor belt with air bearing
Assignee: Baumfolder Corp
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Filing: 1972-10-26
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Granted: 1975-06-17
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Expires: 1992-10-26
Abstract
Abstract A vacuum conveyor system is described comprising a conveyor belt, having vacuum holes therein, combined with means for simultaneously creating positive and negative pressures on the underside of the conveyor belt. The positive pressure acts on portions of the underside of the conveyor belt where there are no vacuum holes and the negative pressure acts through the vacuum holes on articles conveyed by the conveyor belt. The positive pressure tends to establish an air bearing which reduces belt drag while the negative pressure tends to hold conveyed articles tightly against an upper surface of the conveyor belt. A more detailed aspect of the disclosure relates to the size relationship between the belt''s vacuum holes and a passageway which connects the vacuum holes to a vacuum chamber.
Inventors
- 👤 Harold E Boyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:43
CPC Classifications
B; B65; B65G; B65G15/00; B65G15/60; B65G15/30; B65G15/58; B65G21/00; B65G21/20; B65G21/2027; B65G21/2036; B65H; B65H5/00; B65H5/22; B65H5/222; B65H5/224; B65G2201/00; B65G2201/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
243 words
A vacuum-type conveyor system for conveying an article comprising: a conveyor belt having a first side for carrying said article and a second side opposite said first side, said conveyor belt including apertures arranged in a narrow longitudinally extending pervious zone of said conveyor belt, and said conveyor belt further including a longitudinally-extending impervious zone positioned on each side of said pervious zone, said impervious zones being substantially free of apertures and being flat on said second side; a supporting surface adjacent said second side of said conveyor belt, said supporting surface defining an elongated surface negative-pressure zone, said surface negative-pressure zone being adjacent said belt pervious zone and arranged parallel thereto, said supporting surface further defining a plurality of positive pressure apertures arranged in a plurality of elongated areas of said supporting surface, said elongated areas being parallel to, but separated from said surface negative-pressure zone and respectively lying under said impervious zones of said belt; negative fluid-pressure means for creating fluid pressure forces at said surface negative-pressure zone which acts through said surface negative-pressure zone and said belt apertures to hold said article against said first side of said conveyor means; and positive fluid-pressure means for creating positive fluid pressure forces at said positive-pressure apertures which act on said second side of said conveyor at said impervious zone, to create a positive pressure air bearing between said impervious zone and said supporting surface to reduce drag caused by said negative pressure.
Claim 2
Dependent Claim
243 words
A vacuum-type conveyor system for conveying an article comprising: a conveyor belt having a first side for carrying said article and a second side opposite said first side, said conveyor belt including apertures arranged in a narrow longitudinally extending pervious zone of said conveyor belt, and said conveyor belt further including a longitudinally-extending impervious zone positioned on each side of said pervious zone, said impervious zones being substantially free of apertures and being flat on said second side; a supporting surface adjacent said second side of said conveyor belt, said supporting surface defining an elongated surface negative-pressure zone, said surface negative-pressure zone being adjacent said belt pervious zone and arranged parallel thereto, said supporting surface further defining a plurality of positive pressure apertures arranged in a plurality of elongated areas of said supporting surface, said elongated areas being parallel to, but separated from said surface negative-pressure zone and respectively lying under said impervious zones of said belt; negative fluid-pressure means for creating fluid pressure forces at said surface negative-pressure zone which acts through said surface negative-pressure zone and said belt apertures to hold said article against said first side of said conveyor means; and positive fluid-pressure means for creating positive fluid pressure forces at said positive-pressure apertures which act on said second side of said conveyor at said impervious zone, to create a positive pressure air bearing between said impervious zone and said supporting surface to reduce drag caused by said negative pressure.
Claim 3
Dependent Claim
21 words
A vacuum-type conveyor as claimed in claim 1 wherein said belt apertures comprise a single row of holes in said belt.
Claim 4
Dependent Claim
37 words
A vacuum-type conveyor system as claimed in claim 2 wherein: said conveyor means comprises an endless conveyor belt; and said surface negative-pressure zone is a longitudinally oriented slot adjacent to the center line of said eNdless belt.
Claim 5
Dependent Claim
30 words
A vacuum-type conveyor system as claimed in claim 3 wherein each of said plurality of positive pressure apertures comprises apertures arranged in a line substantially parallel to said negative-pressure slot.
Claim 6
Dependent Claim
49 words
A vacuum-type conveyor system as claimed in claim 1 wherein, said surface negative-pressure zone defines a slot and for a given length of conveyor belt, the ratio (W) of the cross-sectional area of said negative-pressure slot to the volume of said belt apertures is more than 0.01 in. 1.
Claim 7
Dependent Claim
38 words
The system of claim 5 wherein, for a given length of said conveyor means, the ratio (W) of the cross-sectional area of said negative-pressure slot to the volume of said belt apertures is less than 1000 in 1.
Claim 8
Dependent Claim
50 words
The system of claim 1 wherein, said surface negative-pressure zone defines a slot and for a given length of said conveyor means, the ratio (W) of the cross-sectional area of said negative-pressure slot to the volume of said belt apertures is between about 0.5 in 1 and 40 in 1.
Claim 9
Dependent Claim
46 words
The system of claim 1 wherein, said surface negative-pressure zone defines a slot and for a given length of said conveyor means, the ratio (Y) of the cross-sectional area of said negative-pressure slot to the cross-sectional area of said belt apertures is more than about 0.02.
Claim 10
Dependent Claim
46 words
The system of claim 1 wherein, said surface negative-pressure zone defines a slot and for a given length of said conveyor means, the ratio (Y) of the cross-sectional area of said negative-pressure slot to the cross-sectional area of said belt apertures is less than about 250.
Claim 11
Dependent Claim
47 words
The system of claim 1 wherein, said surface negative-pressure zone defines a slot and for a given length of said conveyor means, the ratio (Y) of the cross-sectional area of said negative-pressure slot to the cross-sectional area of said positive apertures is between about 0.5 and 20.
Claim 12
Dependent Claim
40 words
The system of claim 1 wherein, for a given length of said conveyor means, the ratio (Z) of the volume of said belt apertures to the cross sectional area of said positive pressure apertures is more than about 0.05 inches.
Claim 13
Dependent Claim
42 words
The system of claim 1 wherein, for a given length of said conveyor means, the ratio (Z) of the volume of said belt apertures in said belt to the cross-sectional area of said positive pressure apertures is less than about 20 inches.
Claim 14
Dependent Claim
41 words
The system of claim 1 wherein, for a given length of said conveyor means, the ratio (Z) of the volume of said belt apertures to the cross-sectional area of said positive pressure apertures is between about 0.1 inches and 10 inches.
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |