Patent US3750904A successfully refreshed from Google Patents.
US3750904A
Expired / Lapsed
US
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Heat treating furnace
Assignee: Electric Furnace Co
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Filing: 1971-06-30
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Granted: 1973-08-07
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Expires: 1991-06-30
Abstract
Abstract A conveyor belt or flat elongated material is pulled in a predetermined direction at a predetermined speed across spacedapart supporting rolls in a heat treating furnace. Alternate ones of the supporting rolls are rotatably driven to move the peripheral surfaces thereof at a speed greater than the predetermined speed and in a direction for imparting frictional forces to the belt or flat elongated material acting in the predetermined direction. The remainder of the rolls are rotatably driven so that the peripheral surfaces thereof move in a manner for imparting frictional forces to the belt or flat elongated material acting opposite to the predetermined direction. Alternate addition and subtraction of forces act on the belt or flat elongated material to provide essentially uniform tension in the belt or flat elongated material to obtain an essentially uniform catenary between rolls. The alternate addition and subtraction of forces maintains at a minimum the tension required to pull the belt or flat elongated material through the furnace.
Inventors
- 👤 L Wisler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:46
CPC Classifications
F; F27; F27B; F27B9/00; F27B9/14; F27B9/20; F27B9/24; F27B9/243; B; B65; B65G; B65G23/00; B65G23/32; B65G23/34
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
254 words
A transport system for a substantially flat elongated article comprising support means for supporting said article and including an entrance support end and an exit support end, tensioning means for tensioning said article to a predetermined tension force between said entrance and exit support ends, article moving means for pulling said article under said predetermined tension force across said support means in a predetermined direction from said entrance support end toward said exit support end at a predetermined speed, said support means including a plurality of spaced-apart friction applying means engaging said article at spaced-apart intervals in said predetermined direction for applying spaced-apart friction forces to said article acting in said predetermined direction, each of said spaced-apart friction forces being substantially less than said predetermined tension force, and a plurality of spaced-apart friction drag applying means engaging said article at spacedapart intervals in said predetermined direction intermediate said friction applying means for applying spaced-apart friction drag forces to said article acting opposite to said predetermined direction, each of said friction drag forces being substantially less than said predetermined tension force and substantially equal to each of said friction forces, said article being under an exit tension force adjacent said exit support end and under an entrance tension force adjacent said entrance support end, said friction applying means and said friction drag applying means being positioned so that said entrance tension force and said exit tension force do not differ by an amount greater than substantially one of said friction forces or friction drag forces.
Claim 2
Dependent Claim
254 words
A transport system for a substantially flat elongated article comprising support means for supporting said article and including an entrance support end and an exit support end, tensioning means for tensioning said article to a predetermined tension force between said entrance and exit support ends, article moving means for pulling said article under said predetermined tension force across said support means in a predetermined direction from said entrance support end toward said exit support end at a predetermined speed, said support means including a plurality of spaced-apart friction applying means engaging said article at spaced-apart intervals in said predetermined direction for applying spaced-apart friction forces to said article acting in said predetermined direction, each of said spaced-apart friction forces being substantially less than said predetermined tension force, and a plurality of spaced-apart friction drag applying means engaging said article at spacedapart intervals in said predetermined direction intermediate said friction applying means for applying spaced-apart friction drag forces to said article acting opposite to said predetermined direction, each of said friction drag forces being substantially less than said predetermined tension force and substantially equal to each of said friction forces, said article being under an exit tension force adjacent said exit support end and under an entrance tension force adjacent said entrance support end, said friction applying means and said friction drag applying means being positioned so that said entrance tension force and said exit tension force do not differ by an amount greater than substantially one of said friction forces or friction drag forces.
Claim 3
Dependent Claim
13 words
The device of claim 1 wherein said article comprises a continuous conveyor belt.
Claim 4
Dependent Claim
49 words
The device of claim 1 wherein said friction applying means and said friction drag applying means act on said article to alternately increase and decrease said predetermined tension therein from said exit end to said entrance end whereby said entrance tension force is less than said exit tension force.
Claim 5
Dependent Claim
29 words
The device of claim 1 wherein said friction applying means comprises a plurality of spaced-apart rotatable rollers, said rollers being rotatable on axes extending transverse to said predetermined direction.
Claim 6
Dependent Claim
54 words
The device of claim 4 wherein each of said rollers has a peripheral surface engaging said article, and roller drive means for rotating said rollers to move said peripheral surfaces thereof at a speed greater than said predetermined speed in a direction to impart frictional forces to said article acting in said predetermined direction.
Claim 7
Dependent Claim
40 words
The device of claim 5 wherein said article comprises a continuous conveyor belt, said article moving means comprising a rotatably driven drum engaging said belt, and a common power source for rotatably driving said drum and said roller drive means.
Claim 8
Dependent Claim
38 words
The device of claim 5 wherein said friction drag applying means comprises a plurality of spaced-apart rotatable extending rollers, said drag rollers being rotatable on axes depending transverse to said predetermined direction intermediate said friction force applying rollers.
Claim 9
Dependent Claim
50 words
The device of claim 7 wherein each of said drag rollers has a peripheral surface engaging said article, and drag roller drive means for rotating said drag rollers to move said peripheral surfaces thereof in a manner for imparting friction forces to said article acting opposite to said predetermined direction.
Claim 10
Dependent Claim
40 words
The device of claim 8 wherein said drag roller drive means is for driving said drag rollers to move said peripheral surfaces thereof at a speed less than said predetermined speed and in the same direction as said predetermined direction.
Claim 11
Dependent Claim
40 words
The device of claim 8 wherein said article comprises a continuous conveyor belt, said article moving means comprising a rotatably driven drum engaging said belt, and a common power source for rotatably driving said drum and said roller drive means.
Claim 12
Dependent Claim
59 words
The device of claim 1 wherein said article comprises a flexible continuous conveyor belt and said article moving means comprises a rotatably driven drum engaging said belt, said belt having a loop therein, and a slack takeup tensioning drum engaging said belt at said loop, said tensioning drum being movable for enlarging or decreasing the size of said loop.
Claim 13
Dependent Claim
76 words
The device of claim 1 wherein said friction drag applying means comprises a plurality of spaced-apart rotatable drag rollers, said drag rollers being rotatable on axes extending transverse to said predetermined direction, each of said drag rollers having a peripheral surface engaging said article, and drag roller drive means for rotating said drag rollers to move said peripheral surfaces thereof in a manner for imparting friction forces to said article acting opposite to said predetermined direction.
Claim 14
Dependent Claim
40 words
The device of claim 12 wherein said drag roller drive means is for driving said drag rollers to move said peripheral surfaces thereof at a speed less than said predetermined speed and in the same direction as said predetermined direction.
Claim 15
Dependent Claim
49 words
The device of claim 1 and further including a heat treating furnace for heat treating parts, said support means being positioned in said furnace and said article comprising a flexible continuous conveyor belt for conveying parts through said furnace, said article moving means comprising a conveyor belt drive means.
Claim 16
Dependent Claim
91 words
The device of claim 14 wherein said conveyor belt drive means comprises said tensioning means for applying said predetermined tension force to said belt adjacent said exit end while pulling said belt across said support means, said friction applying means and said friction drag applying means alternately increasing and decreasing said predetermined tension force in said belt from said exit end to said entrance end whereby said entrance tension force in said belt adjacent said entrance end is not substantially greater than said exit tension force therein adjacent said exit end.
Claim 17
Dependent Claim
103 words
The device of claim 15 wherein said support means includes a pluraltiy of spaced-apart friction applYing rollers and said rollers define said friction applying means, said rollers being spaced-apart in said predetermined direction and being rotatable on axes extending transverse to said predetermined direction, each of said rollers having a peripheral surface, friction applying roller drive means for rotating said rollers to move said peripheral surfaces thereof at a speed greater than said predetermined speed in a direction to impart friction forces to said belt acting in said predetermined direction, and said friction drag applying means being positioned intermediate said friction applying rollers.
Claim 18
Dependent Claim
98 words
The device of claim 16 wherein said support means further includes a plurality of spaced-apart friction applying drag rollers and said drag rollers define said friction drag applying means, said drag rollers being spaced-apart in said predetermined direction and being rotatable on axes extending transverse to said predetermined direction, each of said drag rollers having a peripheral surface engaging said belt intermediate said friction applying rollers, and drag roller drive means for rotating said drag rollers to move said peripheral surfaces thereof in a manner for imparting frictional forces to said belt acting opposite to said predetermined direction.
Claim 19
Dependent Claim
40 words
The device of claim 17 wherein said drag roller drive means is for driving said drag rollers to move said peripheral surfaces thereof at a speed less than said predetermined speed and in the same direction as said predetermined direction.
Claim 20
Dependent Claim
20 words
The device of claim 17 and including a common power means for moving said belt and rotatably driving said rollers.
Claim 21
Independent Claim
197 words
A method of transporting a substantially flat elongated article across support means for supporting said article and having an entrance end and an exit end comprising the steps of; placing predetermined tension force in said article between said entarnce and exit ends, pulling said article under said predetermined tension force across said support means in a predetermined direction from said entrance end toward said exit end at a predetermined speed, applying a plurality of first friction forces to said article at spaced-apart intervals acting in said predetermined direction, each of said first friction forces having a magnitude substantially less than said predetermined tension force, and applying a plurality of friction drag forces to said article at spaced-apart intervals intermediate said first friction forces acting opposite to said predetermined direction, each of said friction drag forces having a magnitude substantially less than said predetermined tension force and substantially equal to each of said first friction forces, whereby said article is under exit tension force adjacent said exit end and under entrance tension forces adjacent said entrance end, and said exit and entrance tesnion forces do not differ by an amount greater than substantially one of said friction forces.
Claim 22
Independent Claim
197 words
A method of transporting a substantially flat elongated article across support means for supporting said article and having an entrance end and an exit end comprising the steps of; placing predetermined tension force in said article between said entarnce and exit ends, pulling said article under said predetermined tension force across said support means in a predetermined direction from said entrance end toward said exit end at a predetermined speed, applying a plurality of first friction forces to said article at spaced-apart intervals acting in said predetermined direction, each of said first friction forces having a magnitude substantially less than said predetermined tension force, and applying a plurality of friction drag forces to said article at spaced-apart intervals intermediate said first friction forces acting opposite to said predetermined direction, each of said friction drag forces having a magnitude substantially less than said predetermined tension force and substantially equal to each of said first friction forces, whereby said article is under exit tension force adjacent said exit end and under entrance tension forces adjacent said entrance end, and said exit and entrance tesnion forces do not differ by an amount greater than substantially one of said friction forces.
Claim 23
Dependent Claim
71 words
The method of claim 20 wherein said support means includes a plurality of spaced-apart first rollers having peripheral surfaces engaging said article and said step of applying said first friction forces to said article is carried out by rotating said rollers to move said peripheral surfaces thereof at a speed greater than said predetermined speed in a direction to impart said first friction forces to said article in said predetermined direction.
Claim 24
Dependent Claim
64 words
The method of claim 21 wherein said support means includes a plurality of spaced-apart drag rollers having peripheral surfaces engaging said article intermediate said first rollers and said step of applying said friction drag forces to said article is carried out by rotating said drag rollers in a manner to apply said friction drag forces to said article acting opposite to said predetermined direction.
Claim 25
Dependent Claim
34 words
The method of claim 22 wherein said drag rollers are driven to move said peripheral surfaces thereof at a speed less than said predetermined speed and in a common direction with said predetermined direction.
Claim 26
Independent Claim
201 words
A method for maintaining low tension and minimizing the magitude of catenaries in a flexible conveyor belt for a heat treating furnace having entrance and exit ends wherein said belt travels in a predetermined direction from said entrance end toward said exit end at a predetermined speed over a plurality of spaced-apart supporting rolls comprising the steps of; placing predetermined tension force in said belt between said entrance and exit ends, pulling said belt under said predetermined tension force through said furnace at said predetermined speed, rotating alternate ones of said rolls to move the peripheral surfaces thereof at a speed greater than said predetermined speed in a direction to impart friction forces to said belt acting in said predetermined direction, and driving the remainder of said rolls in a manner to impart drag frictional forces to said belt acting opposite to said predetermined direction, each of said friction forces having a magnitude substantially less than said predetermined tension force, whereby said belt is under entrance tension force adjacent said entrance end and under exit tension force adjacent said exit end, and said exit and entrance tension forces do not differ by an amount greater than one of said friction forces.
Claim 27
Independent Claim
201 words
A method for maintaining low tension and minimizing the magitude of catenaries in a flexible conveyor belt for a heat treating furnace having entrance and exit ends wherein said belt travels in a predetermined direction from said entrance end toward said exit end at a predetermined speed over a plurality of spaced-apart supporting rolls comprising the steps of; placing predetermined tension force in said belt between said entrance and exit ends, pulling said belt under said predetermined tension force through said furnace at said predetermined speed, rotating alternate ones of said rolls to move the peripheral surfaces thereof at a speed greater than said predetermined speed in a direction to impart friction forces to said belt acting in said predetermined direction, and driving the remainder of said rolls in a manner to impart drag frictional forces to said belt acting opposite to said predetermined direction, each of said friction forces having a magnitude substantially less than said predetermined tension force, whereby said belt is under entrance tension force adjacent said entrance end and under exit tension force adjacent said exit end, and said exit and entrance tension forces do not differ by an amount greater than one of said friction forces.
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) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |