Patent US4828238A successfully refreshed from Google Patents.
US4828238A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Supporting bed for sheet material cutting machine and method of manufacture
Assignee: Crest Foam Industries Inc
•
Filing: 1986-12-15
•
Granted: 1989-05-09
•
Expires: 2006-12-15
Abstract
Abstract A supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the material by means of a vacuum applied from below the supporting bed is manufactured from a sheet of reticulated polyurethane foam material which has been compressed under heat and pressure so as to be permanently reduced to approximately 10-35% of its initial thickness. The degree of compression, the temperature and compression time, and the porosity of the reticulated polyurethane foam starting material are selected to provide particular airflow and firmness characteristics for the finished supporting bed. In a preferred embodiment of the invention, the starting material is a reticulated grafted polyether foam having a porosity of 30 pores per inch and a sheet thickness of 5 inches. The sheet of material is compressed to a thickness of one inch and retained under pressure for 10 minutes at a temperature of about 400° F.
Inventors
- 👤 Michael Mozieka
- 👤 Leo Fisher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:26
CPC Classifications
B; B26; B26D; B26D7/00; B26D7/01; B26D7/018; B26D7/20; B26F; B26F1/00; B26F2210/00; B26F2210/12; Y; Y10; Y10S; Y10S83/00; Y10S83/929; Y10S83/936; Y10S83/939; Y10S83/94; Y10S83/941; Y10T; Y10T83/00; Y10T83/748; Y10T83/929; Y10T83/9309
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
114 words
A method for using a sheet of reticulated foam starting material which has been compressed under heat and pressure so as to be permanently reduced to a thickness no greater than approximately 35% of its initial thickness as a supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the material by means of a vacuum applied from below the supporting bed, said method comprising the steps of placing said sheet of reticulated foam material on said cutting machine as a supporting bed, placing said stack of sheet material thereon and coupling a source of a vacuum to a point underneath said supporting bed and said stack.
Claim 2
Independent Claim
114 words
A method for using a sheet of reticulated foam starting material which has been compressed under heat and pressure so as to be permanently reduced to a thickness no greater than approximately 35% of its initial thickness as a supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the material by means of a vacuum applied from below the supporting bed, said method comprising the steps of placing said sheet of reticulated foam material on said cutting machine as a supporting bed, placing said stack of sheet material thereon and coupling a source of a vacuum to a point underneath said supporting bed and said stack.
Claim 3
Dependent Claim
138 words
A supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the material by means of a vacuum applied from below the supporting bed, said supporting bed comprising a sheet of reticulated foam starting material which has been compressed under heat and pressure so as to be permanently reduced to a thickness no greater than approximately 35% of its initial thickness, the degree of compression, the temperature, the compression time and the porosity of the reticulated foam starting material being selected so that sufficient air flow is obtained through said supporting bed to retain said stack of sheet material in position by means of said vacuum during a cutting operation, and so as to impart sufficient firmness to said supporting bed to avoid substantial vertical compression thereof during said cutting operation.
Claim 4
Dependent Claim
138 words
A supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the material by means of a vacuum applied from below the supporting bed, said supporting bed comprising a sheet of reticulated foam starting material which has been compressed under heat and pressure so as to be permanently reduced to a thickness no greater than approximately 35% of its initial thickness, the degree of compression, the temperature, the compression time and the porosity of the reticulated foam starting material being selected so that sufficient air flow is obtained through said supporting bed to retain said stack of sheet material in position by means of said vacuum during a cutting operation, and so as to impart sufficient firmness to said supporting bed to avoid substantial vertical compression thereof during said cutting operation.
Claim 5
Dependent Claim
40 words
A supporting bed in accordance with claim 2, wherein the starting material is a reticulated polyurethane foam and is compressed for a period of time between 8 minutes and 2 hours at a temperature between 300° F. and 450° F.
Claim 6
Dependent Claim
19 words
A supporting bed in accordance with claim 2 wherein the starting material is a reticulated grafted polyether polyurethane foam.
Claim 7
Dependent Claim
62 words
A supporting bed in accordance with claim 4 wherein the starting material is a sheet approximately five inches thick with a density of about 1.4 pounds per cubic food and a porosity of about 30 pores per inch, the sheet being compressed to a thickness of approximately one inch and maintained at a temperature of about 400° F. for about 10 minutes.
Claim 8
Dependent Claim
62 words
A supporting bed in accordance with claim 4 wherein the starting material is a sheet approximately seven inches thick with a density of about 1.4 pounds per cubic foot and a porosity of about 15 pores per inch, the sheet being compressed to a thickness of approximately one inch and maintained at a temperature of about 400° F. for about 10 minutes.
Claim 9
Dependent Claim
18 words
A supporting bed in accordance with claim 2 wherein the starting material is a reticulated polyester polyurethane foam.
Claim 10
Dependent Claim
58 words
A supporting bed in accordance with claim 7 is a sheet approximately six inches thick with a density of about 2.0 pounds per cubic foot and a porosity of about 10 pores per inch, the sheet being compressed to a thickness of approximately one inch and maintained at a temperature of about 400° F. for about 10 minutes.
Claim 11
Dependent Claim
58 words
A supporting bed in accordance with claim 7 is a sheet approximately seven inches thick with a density of about 2.0 pounds per cubic foot and a porosity of about 10 pores per inch, the sheet being compressed to a thickness of approximately one inch and maintained at a temperature of about 400° F. for about 10 minutes.
Claim 12
Dependent Claim
92 words
A supporting bed in accordance with claim 2, wherein the degree of compression, the temperature, the compression time, and the porosity of the reticulated foam starting material are selected so that a one-inch thick sheet of the supporting bed permits an air flow at least 1.5 CFM through a four square inch area with a pressure drop between the surfaces of the sheet material corresponding to one half inch of water, and so that compressing a 1-inch thick sheet by one-quarter of an inch requires a pressure of at least 1.5 PSl.
Claim 13
Independent Claim
146 words
A method for manufacturing a supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the stack of material by means of a vacuum applied from below the supporting bed, said method comprising the steps of: compressing a sheet of reticulated foam starting material, and simultaneously applying heat thereto so as to permanently reduce said sheet to a thickness no greater than approximately 35% of its initial thickness, the degree of compression, the temperature, the compression time and the porosity of the reticulated foam starting material being selected so that the efficient air flow is obtained through said supporting bed to retain said stack of sheet material in position by means of said vacuum during a cutting operation, and so as to impart sufficient firmness to said supporting bed to avoid substantial vertical compression thereof during said cutting operation.
Claim 14
Independent Claim
146 words
A method for manufacturing a supporting bed for supporting a stack of sheet material in a cutting machine of the type retaining the stack of material by means of a vacuum applied from below the supporting bed, said method comprising the steps of: compressing a sheet of reticulated foam starting material, and simultaneously applying heat thereto so as to permanently reduce said sheet to a thickness no greater than approximately 35% of its initial thickness, the degree of compression, the temperature, the compression time and the porosity of the reticulated foam starting material being selected so that the efficient air flow is obtained through said supporting bed to retain said stack of sheet material in position by means of said vacuum during a cutting operation, and so as to impart sufficient firmness to said supporting bed to avoid substantial vertical compression thereof during said cutting operation.
Claim 15
Dependent Claim
39 words
The method of claim 11, wherein the starting material is a sheet of reticulated polyurethane foam and is compressed for a period of time between 8 minutes and 2 hours at a temperature between 300° F. and 450° F.
Claim 16
Dependent Claim
18 words
The method of claim 11 wherein the starting material is a sheet of reticulated grafted polyether polyurethane foam.
Claim 17
Dependent Claim
62 words
The method of claim 13 wherein the starting material is a sheet approximately five inches thick with a density of about 1.4 pounds per cubic foot and a porosity of about 30 pores per inch, said method comprising compressing said sheet to a thickness of approximately one inch and maintaining it at a temperature of about 400° F. for about 10 minutes.
Claim 18
Dependent Claim
62 words
The method of claim 13 wherein the starting material is a sheet approximately seven inches thick with a density of about 1.4 pounds per cubic foot and a porosity of about 15 pores per inch, said method comprising compressing said sheet to a thickness of approximately one inch and maintaining it at a temperature of about 400° F. for about 10 minutes.
Claim 19
Dependent Claim
17 words
The method of claim 11 wherein the starting material is a sheet of reticulated polyester polyurethane foam.
Claim 20
Dependent Claim
59 words
The method of claim 16 wherein said sheet is approximately six inches thick with a density of about 2.0 pounds per cubic foot and a porosity of about 10 pores per inch, said method comprising compressing the sheet to a thickness of approximately one inch and maintaining it at a temperature of about 400° F. for about 10 minutes.
Claim 21
Dependent Claim
59 words
The method of claim 16 wherein said sheet is approximately seven inches thick with a density of about 2.0 pounds per cubic foot and a porosity of about 10 pores per inch, said method comprising compressing said sheet to a thickness of approximately one inch and maintaining it at a temperature of about 400° F. for about 10 minutes.
Claim 22
Dependent Claim
92 words
A method in accordance with claim 11 wherein the degree of compression, the temperature, the compression time, and the porosity of the reticulated foam starting material are selected so that a one-inch thick sheet of the supporting bed permits an air flow at least 1.5 CFM through a four square inch area with a pressure drop between the surfaces of the sheet material corresponding to one half inch of water, and so that compressing a 1-inch thick sheet by one quarter of an inch requires a pressure of at least 1.5 PSI.
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) | 1992-05-08 | 1992-11-07 | 1993-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-08 | 1996-11-07 | 1997-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-08 | 2000-11-07 | 2001-05-09 | $7700.00 | Window Closed / Lapsed |