Patent US3796455A successfully refreshed from Google Patents.
US3796455A
Expired / Lapsed
US
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Air flow actuated overhead pickup device for limp sheet materials
Assignee: Unimation Inc
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Filing: 1972-09-05
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Granted: 1974-03-12
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Expires: 1992-09-05
Abstract
Abstract An air flow actuated overhead pickup device for discrete pieces of limp sheet material comprises a perforated support member for contact with the upper surface of the pieces of material to be picked up, said support member being dimensioned to define an outer marginal edge portion extending outwardly of the peripheral outer edge of the piece of sheet material being handled; means defining a plurality of inwardly convergent, high velocity, air flow channels extending from segments of said outer edge portion inwardly toward a common plenum chamber centrally positioned above the support member, said air flow channels including an increasing flow cross section toward the inner ends adjacent the plenum chamber thereby reducing the air flow velocity below that adjacent the outer edge portion; and fan means connected to the plenum chamber for maintaining a high velocity air flow inwardly through the channels, said fan means having an operating characteristic of essentially constant pressure over a broad volume range.
Inventors
- 👤 T Linkbom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:05
CPC Classifications
B; B66; B66C; B66C1/00; B66C1/02; B66C1/0281; B65; B65H; B65H3/00; B65H3/08; B65H3/0808; B65H3/0816; B65H3/0883; B66C1/0256; B66C1/0293; B65H2406/00; B65H2406/30; B65H2406/36; B65H2406/366; B65H2406/3662; B65H2701/00; B65H2701/10; B65H2701/17; B65H2701/174; B65H2701/175; B65H2701/1752; B65H2701/19; B65H2701/1938
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
222 words
An overhead pickup device suitable for picking up irregulArly shaped pieces of limp, flexible sheet material comprising: means forming a perforate, planar support structure for engaging the upper surface of a piece of sheet material picked up by said device, said support structure having an area extending outwardly around the peripheral edge of said piece of sheet material in contact therewith, said structure having perforations defined therein distributed substantially uniformly over the entire surface area thereof, said perforations having a total area comprising a substantial portion of said entire surface area, flow chamber means above and in communication at its lower end with the entire area of said support structure joining and enclosing the periphery thereof, said flow chamber means having a cover wall spaced a minimum height above said support structure around said periphery and sloping upwardly to a maximum height above said structure adjacent the center of said area; plenum chamber means in communication with said flow chamber means adjacent the center of said area having a cross section flow area substantially greater than than the effective cross-sectional flow area of said flow chamber means between said periphery and said center; and fan means in suction communication with said plenum chamber means for moving air through said perforate support structure at high velocity flow rates at essentially constant low pressure.
Claim 2
Dependent Claim
222 words
An overhead pickup device suitable for picking up irregulArly shaped pieces of limp, flexible sheet material comprising: means forming a perforate, planar support structure for engaging the upper surface of a piece of sheet material picked up by said device, said support structure having an area extending outwardly around the peripheral edge of said piece of sheet material in contact therewith, said structure having perforations defined therein distributed substantially uniformly over the entire surface area thereof, said perforations having a total area comprising a substantial portion of said entire surface area, flow chamber means above and in communication at its lower end with the entire area of said support structure joining and enclosing the periphery thereof, said flow chamber means having a cover wall spaced a minimum height above said support structure around said periphery and sloping upwardly to a maximum height above said structure adjacent the center of said area; plenum chamber means in communication with said flow chamber means adjacent the center of said area having a cross section flow area substantially greater than than the effective cross-sectional flow area of said flow chamber means between said periphery and said center; and fan means in suction communication with said plenum chamber means for moving air through said perforate support structure at high velocity flow rates at essentially constant low pressure.
Claim 3
Dependent Claim
28 words
The pickup device of claim 1 wherein said fan means comprises a centrifugal blower having an essentially relative constant pressure output over a wide range of flow rates.
Claim 4
Dependent Claim
17 words
The pickup device of claim 1 wherein said support structure comprises screen means of woven elongated strands.
Claim 5
Dependent Claim
17 words
The pickup device of claim 1 wherein support structure comprises a pad of open celled foam material.
Claim 6
Dependent Claim
12 words
The pickup device of claim 4 wherein said foam material is nonrigid.
Claim 7
Dependent Claim
46 words
The pickup device of claim 1 including a plurality of flow guiding vanes extending between said cover wall and said support structure in said flow chamber means for guiding air flow from said periphery toward said plenum chamber means with a gradual reduction in flow velocity.
Claim 8
Dependent Claim
31 words
The pickup device of claim 6 wherein said vanes are arranged on convergent paths toward said center forming flow channels of ever increasing cross-section area from said periphery toward said center.
Claim 9
Dependent Claim
29 words
The pickup device of claim 6 wherein said vanes are connected along their lower edges to said support structure and along their upper edges to said flow chamber means.
Claim 10
Dependent Claim
190 words
An overhead pickup device adapted for picking up irregularly shaped discrete pieces of limp sheet material comprising a perforated support member for contact with the upper surface of a piece of said sheet material to be picked up, said support member having a plurality of perforations therein distributed substantially uniformly over the entire surface thereof and dimensioned to define a marginal outer edge portion extending outwardly around the peripheral edge of said piece, said perforations having a total area comprising a substantial portion of said entire surface area; means defining a plurality of inwardly covergent flow channels extending inwardly from said outer edge portion toward a common plenum chamber centrally positioned above said support member, said channels having a progressively increasing flow cross-section inwardly of said outer edge portion to gradually reduce the velocity of flow between said outer edge portion and said plenum chamber; and fan means connected to said plenum chamber for drawing air inwardly through said channels from the outer ends adjacent said outer periphery of said piece of material, said fan means having a characteristic of an essentially constant pressure over a wide volume flow range.
Claim 11
Dependent Claim
190 words
An overhead pickup device adapted for picking up irregularly shaped discrete pieces of limp sheet material comprising a perforated support member for contact with the upper surface of a piece of said sheet material to be picked up, said support member having a plurality of perforations therein distributed substantially uniformly over the entire surface thereof and dimensioned to define a marginal outer edge portion extending outwardly around the peripheral edge of said piece, said perforations having a total area comprising a substantial portion of said entire surface area; means defining a plurality of inwardly covergent flow channels extending inwardly from said outer edge portion toward a common plenum chamber centrally positioned above said support member, said channels having a progressively increasing flow cross-section inwardly of said outer edge portion to gradually reduce the velocity of flow between said outer edge portion and said plenum chamber; and fan means connected to said plenum chamber for drawing air inwardly through said channels from the outer ends adjacent said outer periphery of said piece of material, said fan means having a characteristic of an essentially constant pressure over a wide volume flow range.
Claim 12
Dependent Claim
39 words
The overhead pickup device of claim 9 wherein said means defining said flow channels comprises a hood structure having a peripheral edge member and a top wall sloping inwardly of said edge member upwardly to join said plenum chamber.
Claim 13
Dependent Claim
40 words
The overhead pickup device of claim 10 wherein said top wall is formed with an opening at the center thereof and said plenum chamber includes a peripheral sidewall joined along its lower edge to said top wall around said opening.
Claim 14
Dependent Claim
37 words
The overhead pickup device of claim 10 wherein said means defining said flow channels include a plurality of dividers between said top wall and said support member extending inwardly of said edge member toward said plenum chamber.
Claim 15
Dependent Claim
24 words
The overhead pickup device of claim 12 wherein said dividers are spaced apart to diverge away from each other outwardly of said plenum chamber.
Claim 16
Dependent Claim
29 words
The overhead pickup device of claim 10 wherein said plenum chamber includes a top wall having a central opening therein in communication with the inlet of said fan means.
Claim 17
Dependent Claim
30 words
The overhead pickup device of claim 14 wherein the cross sectional flow area of said plenum chamber is substantially greater than the maximum flow cross sections of said flow channels.
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) | 1977-03-11 | 1977-09-10 | 1978-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-11 | 1981-09-10 | 1982-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-11 | 1985-09-10 | 1986-03-12 | $7700.00 | Window Closed / Lapsed |