US3265780A - Method curing a foam insitu using a changing mode microwave generator - Google Patents
Method curing a foam insitu using a changing mode microwave generator Download PDFInfo
- Publication number
- US3265780A US3265780A US269975A US26997563A US3265780A US 3265780 A US3265780 A US 3265780A US 269975 A US269975 A US 269975A US 26997563 A US26997563 A US 26997563A US 3265780 A US3265780 A US 3265780A
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- foam
- space
- antenna
- microwave
- microwaves
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Links
- 239000006260 foam Substances 0.000 title claims description 12
- 238000000034 method Methods 0.000 title claims description 10
- 239000000463 material Substances 0.000 claims description 25
- 239000006261 foam material Substances 0.000 claims description 8
- 238000007599 discharging Methods 0.000 claims description 4
- 238000009413 insulation Methods 0.000 description 24
- 210000004027 cell Anatomy 0.000 description 8
- 239000004721 Polyphenylene oxide Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 229920000570 polyether Polymers 0.000 description 5
- 238000001723 curing Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 229920005830 Polyurethane Foam Polymers 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 210000002421 cell wall Anatomy 0.000 description 2
- 230000002500 effect on skin Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005187 foaming Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000011496 polyurethane foam Substances 0.000 description 2
- 238000009827 uniform distribution Methods 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 description 1
- 235000019687 Lamb Nutrition 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 description 1
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 description 1
- 229930006000 Sucrose Natural products 0.000 description 1
- 239000012190 activator Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 150000004985 diamines Chemical class 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000010097 foam moulding Methods 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 239000003562 lightweight material Substances 0.000 description 1
- 238000011415 microwave curing Methods 0.000 description 1
- 239000011490 mineral wool Substances 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- -1 organo silicon Chemical compound 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000005720 sucrose Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 239000002937 thermal insulation foam Substances 0.000 description 1
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 description 1
- RUELTTOHQODFPA-UHFFFAOYSA-N toluene 2,6-diisocyanate Chemical compound CC1=C(N=C=O)C=CC=C1N=C=O RUELTTOHQODFPA-UHFFFAOYSA-N 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/34—Auxiliary operations
- B29C44/3415—Heating or cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/02—Moulds or cores; Details thereof or accessories therefor with incorporated heating or cooling means
- B29C33/06—Moulds or cores; Details thereof or accessories therefor with incorporated heating or cooling means using radiation, e.g. electro-magnetic waves, induction heating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/762—Household appliances
- B29L2031/7622—Refrigerators
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S521/00—Synthetic resins or natural rubbers -- part of the class 520 series
- Y10S521/915—Utilizing electrical or wave energy during cell forming process
Definitions
- This invention pertains to a method of manufacture and more particularly to a method of and apparatus for filling a space with foam material.
- T he excellent insulating efficiency the light weight and structural reinforcing ability of substantially rigid foam materials has been recognized.
- many molds are required.
- the cell structure of the foam is not uniform on account of the heat dissipating effect of the walls of the mold and other temperature differences. This: lack of. uniforr nity causes the foam material to be more dense and less etficient in insulating effect in some areas. Temperature differences and differences in thermal expansion cause tearing and rupturing of the cells.
- the microwave antenna may be provided with a rotary stirrer to make more uniform the penetration of the microwaves throughout the insulation space of the refrigerator cabinet.
- the discharge of the microwave energy into the foam-forming materials speeds the reaction and also makes the reaction more uniform, thereby producing a more uniform cell structure with a lower density and more impervious cell walls.
- FIGURE 1 is a vertical, longitudinal sectional view through a partially foamed refrigerator cabinet and microwave generating apparatus illustrating one form of my improved method and apparatus; 7
- FIGURE 2 is an enlarged vertical sectional view of the microwave antenna and mode changing means such as a wave stirrer shown in FIGURE v1; and y FIGURE 3 is a view in elevation of a modified form United States Patent 3,265,736 Patented August 9, 1966 "ice of microwave carrying connection between the microwave generator and the microwave antenna.
- a refrigerator cabinet 20 provided with anouter metal shell 22 preferably of sheet steel, an inner metal liner 24 likewise of sheet steel and a plastic breakerstrip 26 extending completely around the door opening connecting the inner liner 24 and the outer shell 22.
- an outer metal shell 22 preferably of sheet steel
- an inner metal liner 24 likewise of sheet steel
- a plastic breakerstrip 26 extending completely around the door opening connecting the inner liner 24 and the outer shell 22.
- a strip 28 of glass fiber or mineral wool extending completely around the door opening of the cabinet beneath the breaker strip 26.
- the cabinet 20 is placed with its open side face down upon a supporting platform 30 preferably of sheet steel.
- the back wall of the cabinet 20 is provided with a filler opening 42 through which the foam-forming material 44 is discharged into the insulation space 45 between the inner liner 24 and the outer shell 22.
- the foam-forming ma- I terial issues from a mixer 46.
- the foam-forming material is ordinarily composed of two components: an A component which is circulated through the conduit and the valve chamber and, when not discharged into the cabinet, is returned through a return conduit 52 to the circulating system; the B component is circulated through the conduit 54 to the valve chamber 50 and, when not required, is returned through a separate conduit 56 to the recirculating system.
- both A and B components are delivered concurrently in proper proportions from the valve chamber 50 into a mixing chamber 51 from which the mixed components are delivered from an outlet 53 through the aperture 42 into the insulation space 45.
- the mixing apparatus 46 is withdrawn and the opening 42 is covered by a metal plate 58.
- Dilferent temperatures were attained in different zones causing different speeds of reaction within the insulation space which not only caused a lack of uniformity in density and size but also produced undesirable skin effects as well as tearing of the insulation and rupturing of the cells and also left voids in certain locations. This all reduced the quality and effectiveness of the insulation material and made some portions structurally weak.
- microwave energy is simultaneously introduced through the introduction of a microwave antenna into the space.
- a stirrer in conjunction with the microwave antenna assures substantially uniform distribution of the microwaves throughout the insulation space. This speeds and makes more uniform the reaction and also insures the attainment of substantially uniform temperatures, thereby producing a more impervious foam with more uniform density and cell size and more uniform filling of the insulation cavity.
- a microwave generator 60 having a magnetron tube 62 projecting into the wave guide 64.
- the wave guide 64 extends from the magnetron tube to a receiver radiator dipole antenna 66 which projects from the upper wall of the wave guide 64 down through an opening 68 into the insulation space 45.
- the microwave energy generated by the generator 60 is transmitted from magnetron tube 62 to the dipole antenna 66.
- the portion of the dipole antenna 66 within the cabinet wall insulation space 45 reradiates the microwaves within the insulation space to be absorbed bythefoam-forming materials.
- the sleeve 76 is provided with spaced nylon bearings 78 and 80 for its rotatable mounting upon the stub antenna 66.
- the sleeve 76 is also rotatably mounted in-a flanged plate 82 which covers the aperture 68 in the rear wall 40. A portion of the sleeve 76 extends into the wave guide 64 and is provided with an integral pulley 84 thereon.
- This pulley 84 is connected by a belt 86 driven by a pulley 88 upon the drive shaft of an electric motor 90.
- the motor 90 is operated concurrently with the operation of the microwave generator so that a substantially uniform distribution of the microwave energy throughout the insulation space 45 is assured while the generator 60 is in operation. 7
- FIGURE 3 a modified form of the invention is shown in which the microwave generator 12-1 is directly connected through a coaxial cable'123 with the stub antenna 125 extending into the insulation space 45 as in FIGURE 1.
- the mode changing means or stirrer 127 is substantially identical to the stirrer 70 and includes the metal plate 129 similar to the metal plate 72. It is also rot'ata-bly mounted by suitable bearings upon the antenna 125 and is also rotatably mounted within the flanged plate 131 which covers the opening 68 in the rear wall 40 of the outer shell 22. Instead of providing a pulley upon the stirrer 1.27, there is provided gear teeth 133 above the cover 131 upon the upper extension of the stirrer 127.
- gear teeth 133 are engaged by a driver gear 135'mounted on the drive shaft of the electric motor 137.
- the microwave generator 121 and the electric motor 137 are 0perated simultaneously to discharge microwaves within the insulation space and to distribute these waves substantially uniformly throughout the insulation space 45.
- a component As one specific example of the foam-forming material suitable for introduction into the insulation space 45 for subsequent or simultaneous processing utilizing the facility and beneficial effects afforded by microwave energy, for the A component, there is employed 100 parts by weight of a prepolymer made from 79 parts by weight of a polydnsocyanate mixture comprising 80 parts by weight of 2,4 toluene diisocyanate and 20 parts by weight of 2,6 toluene diisocyan ate together with 21 parts by weight of a polyether A as defined hereafter. This component is continuously circulated through the conduit 48, the valve chamber 50. and the return conduit 52.
- the B component circulates independently through the valvechamber from the conduit 54 to the conduit 56.
- the B component is composed of 87 parts by weight of the same polyether A as defined hereinafter to 3 parts by weight ofan activator consisting of 2 parts by weight of tetramethylhutane diamine and 1 part by weight of organo silicon surfactant and 38 parts by weight of trichloromonofiuoromethane.
- the polyether A is made up of sucrose 1 part; propylene oxide ll parts; ethylene oxide 4 parts; OH number 445 to 470; water maximum by weight .15 viscosity cps. at 25 C. 22,000 to 32,000; and pH 3.5 to 5. All these quantities in the formula for the polyether A are expressed in mols unless otherwise noted.
- valve chamber 50 These materials, through suitable dual valving arrangements in the valve chamber 50, are separately introduced into the mixing chamber 51 of the mixer 46 in proportion of parts by weight of the A or prepolymer component to 128 parts by weight of the B polyether component. This mixture is discharged into the insulation space 45 through the opening 42 in the rear wall 40.
- the microwave energy is introduced into the insulation space 45 preferably during the introduction and the foamingand curing of the foam-forming materials 44.
- I introduce microwaves at 2450 megacycles frequency.
- I mean electromagnetic wave energy having a frequency in the range of about ten to the seventh power (10 to ten to the thirteenth power (10 cycles per second.
- the foam-forming materials are introduced into the and, since it has not substantially reacted chemically yet,
- the foam material expands under comparatively light pressures, minimizing expansion pressures and the need for supporting the walls of the inner liner 24 and the outer shell 22. It also result-s in a lighter, more uniform cell structure having more uniform structural strength and insulating value. It minimizes the occurrence of voids in the insulation, skin effects and the shearing and tearing characteristics of'materials reacted and expanded to foam by exothermic heat in the conventional methods or process not utilizing microwave energy. The entire foaming operation takes place more quickly so that less space is require-d, on the production linefor this particular operation. This makes the use of the foam-forming material more economical and makes it possible to extend their use to many more places wherein it is desired to fill a space with a lightweight material having excellent structural properties.
- foam-forming materials which may be used, it is evident thatthe invention applies to many foam-forming materials suchas epoxy foams and especially those whose reaction is exothermic.
- the antenna or radiating means and the mode changing means may vary in detail, design, speed or orbit of rotation or it may be integral with or part of the material mixing head. There may be several such radiating mixing means--individually or in combination design concept.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
- Polyurethanes Or Polyureas (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Description
g- 9 1966 A G. B. LONG 3,265,780
METHOD CURING A FOAM INSITU USING A CHANGING MODE MICROWAVE GENERATOR Filed April 2, 1963 A 9 0 86 s e2 50 5 3 42 88 [Ll/J33 N v INVENTOR George 8. Long more impervious cell walls.v
George B. Long, DaytomOhio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Apr. 2, 1963, Ser. No. 269,975
2Claims. (Cl. 264 -26) This invention pertains to a method of manufacture and more particularly to a method of and apparatus for filling a space with foam material.
T he excellent insulating efficiency, the light weight and structural reinforcing ability of substantially rigid foam materials has been recognized. However, whenthese materials are used in high volume production, many molds are required. Further, the cell structure of the foam is not uniform on account of the heat dissipating effect of the walls of the mold and other temperature differences. This: lack of. uniforr nity causes the foam material to be more dense and less etficient in insulating effect in some areas. Temperature differences and differences in thermal expansion cause tearing and rupturing of the cells.
It is an object of this invention to provide amethod of and apparatus for rapidly filling a space by inserting the foam-forming materials and a microwave antenna into the space and discharging microwave electromagnetic ener'gy from the antenna into the foam-forming materials in the space to produce rapidly a foam having a more uniform cell structure with a lower uniform density and It is another object of this invention to provide a method of and apparatus for rapidly filling a space by inserting the foam-forming materials and a microwave antenna into the space and discharging microwave electromagnetic energy from the antenna into the foarn-forming materials in the space at the optimum frequency and power for a sutficient time to control and make more uniform the reaction of the foam-forming materials for providing a foam of superior insulating properties.
These and other objects are attained in the forms shown foaming operation. The microwave antenna may be provided with a rotary stirrer to make more uniform the penetration of the microwaves throughout the insulation space of the refrigerator cabinet. The discharge of the microwave energy into the foam-forming materials speeds the reaction and also makes the reaction more uniform, thereby producing a more uniform cell structure with a lower density and more impervious cell walls.
Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention areclearly shown.
In the drawings:
FIGURE 1 is a vertical, longitudinal sectional view through a partially foamed refrigerator cabinet and microwave generating apparatus illustrating one form of my improved method and apparatus; 7
FIGURE 2 is an enlarged vertical sectional view of the microwave antenna and mode changing means such as a wave stirrer shown in FIGURE v1; and y FIGURE 3 is a view in elevation of a modified form United States Patent 3,265,736 Patented August 9, 1966 "ice of microwave carrying connection between the microwave generator and the microwave antenna.
Referring now more particulary to FlGURE 1, there is shown a refrigerator cabinet 20 provided with anouter metal shell 22 preferably of sheet steel, an inner metal liner 24 likewise of sheet steel and a plastic breakerstrip 26 extending completely around the door opening connecting the inner liner 24 and the outer shell 22. To pro vide a space for refrigerant conduits and electric wiring beneath the breaker strip 26, there is provided a strip 28 of glass fiber or mineral wool extending completely around the door opening of the cabinet beneath the breaker strip 26. Y The cabinet 20 is placed with its open side face down upon a supporting platform 30 preferably of sheet steel. The back wall of the cabinet 20 is provided with a filler opening 42 through which the foam-forming material 44 is discharged into the insulation space 45 between the inner liner 24 and the outer shell 22. The foam-forming ma- I terial issues from a mixer 46. The foam-forming material is ordinarily composed of two components: an A component which is circulated through the conduit and the valve chamber and, when not discharged into the cabinet, is returned through a return conduit 52 to the circulating system; the B component is circulated through the conduit 54 to the valve chamber 50 and, when not required, is returned through a separate conduit 56 to the recirculating system. When desired, both A and B components are delivered concurrently in proper proportions from the valve chamber 50 into a mixing chamber 51 from which the mixed components are delivered from an outlet 53 through the aperture 42 into the insulation space 45. When a suffiicent amount of the components have been discharged into the insulation space to eventually fill the space 45, the mixing apparatus 46 is withdrawn and the opening 42 is covered by a metal plate 58.
One of the difiiculties encountered Wit-h the casting of foam material in the insulation space was that the exothermic reaction took a considerable period of time. and curing was required. Because of the excessive pressures generated, molds to prevent bulging and distortion of the walls also were required until the curing was completed. In high volume production, therefore, many of these molds were required. Some of these molds were relatively expensive thereby incurring a relatively high initial cost to achieve volume production. Even though this investment was made, there was a lack of uniformity in the insulation. Some portions of the insulation foam would have a relatively low density and other portions would be provided'with a relatively high density. Also, the size of the cells were not uniform throughout the mass of insulation. Dilferent temperatures were attained in different zones causing different speeds of reaction within the insulation space which not only caused a lack of uniformity in density and size but also produced undesirable skin effects as well as tearing of the insulation and rupturing of the cells and also left voids in certain locations. This all reduced the quality and effectiveness of the insulation material and made some portions structurally weak.
According to my invention, throughout the casting of the foam material in the insulation space and especially prior to the exothermic reaction and resulting higher pressures, microwave energy is simultaneously introduced through the introduction of a microwave antenna into the space. A stirrer in conjunction with the microwave antenna assures substantially uniform distribution of the microwaves throughout the insulation space. This speeds and makes more uniform the reaction and also insures the attainment of substantially uniform temperatures, thereby producing a more impervious foam with more uniform density and cell size and more uniform filling of the insulation cavity. As shown in FIGURE 1, there is provided a microwave generator 60 having a magnetron tube 62 projecting into the wave guide 64. The wave guide 64 extends from the magnetron tube to a receiver radiator dipole antenna 66 which projects from the upper wall of the wave guide 64 down through an opening 68 into the insulation space 45. The microwave energy generated by the generator 60 is transmitted from magnetron tube 62 to the dipole antenna 66. The portion of the dipole antenna 66 within the cabinet wall insulation space 45 reradiates the microwaves within the insulation space to be absorbed bythefoam-forming materials.
' mounted at oneend of the sleeve whilethe plate 72 is mounted at an'intermediate point on the sleeve, all within the insulation space 45. The aperture 68 in the rear wall 40 is made large enough that the plates 72 and 74 may readily pass through it. Thesleeve 76 is provided with spaced nylon bearings 78 and 80 for its rotatable mounting upon the stub antenna 66. The sleeve 76 is also rotatably mounted in-a flanged plate 82 which covers the aperture 68 in the rear wall 40. A portion of the sleeve 76 extends into the wave guide 64 and is provided with an integral pulley 84 thereon. This pulley 84 is connected by a belt 86 driven by a pulley 88 upon the drive shaft of an electric motor 90. The motor 90 is operated concurrently with the operation of the microwave generator so that a substantially uniform distribution of the microwave energy throughout the insulation space 45 is assured while the generator 60 is in operation. 7
In FIGURE 3, a modified form of the invention is shown in which the microwave generator 12-1 is directly connected through a coaxial cable'123 with the stub antenna 125 extending into the insulation space 45 as in FIGURE 1. The mode changing means or stirrer 127 is substantially identical to the stirrer 70 and includes the metal plate 129 similar to the metal plate 72. It is also rot'ata-bly mounted by suitable bearings upon the antenna 125 and is also rotatably mounted within the flanged plate 131 which covers the opening 68 in the rear wall 40 of the outer shell 22. Instead of providing a pulley upon the stirrer 1.27, there is provided gear teeth 133 above the cover 131 upon the upper extension of the stirrer 127. These gear teeth 133 are engaged by a driver gear 135'mounted on the drive shaft of the electric motor 137. Preferably, the microwave generator 121 and the electric motor 137 are 0perated simultaneously to discharge microwaves within the insulation space and to distribute these waves substantially uniformly throughout the insulation space 45.
"As one specific example of the foam-forming material suitable for introduction into the insulation space 45 for subsequent or simultaneous processing utilizing the facility and beneficial effects afforded by microwave energy, for the A component, there is employed 100 parts by weight of a prepolymer made from 79 parts by weight of a polydnsocyanate mixture comprising 80 parts by weight of 2,4 toluene diisocyanate and 20 parts by weight of 2,6 toluene diisocyan ate together with 21 parts by weight of a polyether A as defined hereafter. This component is continuously circulated through the conduit 48, the valve chamber 50. and the return conduit 52.
The B component circulates independently through the valvechamber from the conduit 54 to the conduit 56. The B component is composed of 87 parts by weight of the same polyether A as defined hereinafter to 3 parts by weight ofan activator consisting of 2 parts by weight of tetramethylhutane diamine and 1 part by weight of organo silicon surfactant and 38 parts by weight of trichloromonofiuoromethane. The polyether A is made up of sucrose 1 part; propylene oxide ll parts; ethylene oxide 4 parts; OH number 445 to 470; water maximum by weight .15 viscosity cps. at 25 C. 22,000 to 32,000; and pH 3.5 to 5. All these quantities in the formula for the polyether A are expressed in mols unless otherwise noted. These materials, through suitable dual valving arrangements in the valve chamber 50, are separately introduced into the mixing chamber 51 of the mixer 46 in proportion of parts by weight of the A or prepolymer component to 128 parts by weight of the B polyether component. This mixture is discharged into the insulation space 45 through the opening 42 in the rear wall 40.
The microwave energy is introduced into the insulation space 45 preferably during the introduction and the foamingand curing of the foam-forming materials 44. As one specific example, I introduce microwaves at 2450 megacycles frequency. By microwave energy, I mean electromagnetic wave energy having a frequency in the range of about ten to the seventh power (10 to ten to the thirteenth power (10 cycles per second.
The foam-forming materials are introduced into the and, since it has not substantially reacted chemically yet,
the foam material expands under comparatively light pressures, minimizing expansion pressures and the need for supporting the walls of the inner liner 24 and the outer shell 22. It also result-s in a lighter, more uniform cell structure having more uniform structural strength and insulating value. It minimizes the occurrence of voids in the insulation, skin effects and the shearing and tearing characteristics of'materials reacted and expanded to foam by exothermic heat in the conventional methods or process not utilizing microwave energy. The entire foaming operation takes place more quickly so that less space is require-d, on the production linefor this particular operation. This makes the use of the foam-forming material more economical and makes it possible to extend their use to many more places wherein it is desired to fill a space with a lightweight material having excellent structural properties.
While I have given one specific example of foam-forming materials which may be used, it is evident thatthe invention applies to many foam-forming materials suchas epoxy foams and especially those whose reaction is exothermic.
The antenna or radiating means and the mode changing means may vary in detail, design, speed or orbit of rotation or it may be integral with or part of the material mixing head. There may be several such radiating mixing means--individually or in combination design concept.
While the embodiments of the present invention, as herein disclosed, constitute preferred forms, it is to he understood that other forms might be adopted.
What is claimed is as follows:
1. The process of filling a space with foam material comprising:
(a) inserting into said space heatvresponsive reactive foam-forming material,
(b) inserting intosaid space a microwave antenna in operative relation with a microwave generator located outside said space,
(c) inserting into said space a rotatable microwave stirrer,
(d) reacting said foam-forming material within said space to form a foam,
(e) at the beginning of and during the reaction of said foam-forming material generating microwaves outside said space, transmitting said microwaves to said antenna and discharging said microwaves from said antenna within said space and (f) repeatedly changing discharged from said antenna by rotating said stirrer.
2. The process of claim 1 in which the foam formed within said space is a polyurethane foam.
References Cited by the Examiner UNITED STATES PATENTS 7 3,265,780 5 6 the mode of said microwaves FOREIGN PATENTS 4/1961 Great Britain. OTHER REFERENCES 5 Lanigan, W. 1.: Microwave curing of flexible polyurethane foam mouldings. In British Plastics, October Modem Plastics: Gas Refrigerator,
Seifried et a]. X Urethane Foam Brings Back the Zakski vol. 38, N0. 8, April 1961, pp. 96-98. 26445 ALEXANDER H. BRODMERKEL,
Smlth Examiner Bird 26447 Long -219 10 55 P. E. ANDERSON, Assistant Examiner.
Lamb 219-1055 Jacobs 264-54 x 15
Claims (1)
1. THE PROCESS OF FILLING A SPACE WITH FOAM MATERIAL COMPRISING: (A) INSERTING INTO SAID SPACE HEAT-RESPONSIVE REACTIVE FOAM-FORMING MATERIAL, (B) INSERTING INTO SAID SPACE A MICROWAVE ANTENNA IN OPERATIVE RELATION WITH A MICROWAVE GENERATOR LOCATED OUTSIDE SAID SPACE, (C) INSERTING INTO SAID SPACE A ROTATABLE MICROWAVE STIRRER, (D) REACTING SAID FOAM-FORMING MATERIAL WITHIN SAID SPACE TO FORM A FOAM, (E) AT THE BEGINNING OF AND DURING THE REACTION OF SAID FOAM-FORMING MATERIAL GENERATING MICROWAVES OUTSIDE SAID SPACE, TRANSMITTING SAID MICROWAVES TO SAID ANTENNA AND DISCHARGING SAID MICROWAVES FROM SAID ANTENNA WITHIN SAID SPACE AND (F) REPEATEDLY CHANGING THE MODE OF SAID MICROWAVES DISCHARGED FROM SAID ANTENNA BY ROTATING SAID STIRRER.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
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US269975A US3265780A (en) | 1963-04-02 | 1963-04-02 | Method curing a foam insitu using a changing mode microwave generator |
GB9328/64A GB1032219A (en) | 1963-04-02 | 1964-03-05 | Methods of producing foam-insulated products |
Applications Claiming Priority (1)
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US269975A US3265780A (en) | 1963-04-02 | 1963-04-02 | Method curing a foam insitu using a changing mode microwave generator |
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US3265780A true US3265780A (en) | 1966-08-09 |
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US269975A Expired - Lifetime US3265780A (en) | 1963-04-02 | 1963-04-02 | Method curing a foam insitu using a changing mode microwave generator |
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GB (1) | GB1032219A (en) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3326787A (en) * | 1963-09-05 | 1967-06-20 | Gen Motors Corp | Method of manufacturing polyurethane foam using a gas to create sonic energy |
DE2622173A1 (en) * | 1975-05-19 | 1976-12-02 | Matsushita Electric Ind Co Ltd | DEVICE FOR HEATING AN OBJECT WITH HIGH FREQUENCY RADIATION, IN PARTICULAR MICROWAVE OVEN |
US4086813A (en) * | 1975-12-22 | 1978-05-02 | General Electric Company | Microwave oven food temperature sensing probe assembly including a reflector |
US4144437A (en) * | 1977-07-29 | 1979-03-13 | Litton Systems, Inc. | Microwave oven energy stirrer |
US4173608A (en) * | 1976-10-22 | 1979-11-06 | Isobox-Barbier | Process and apparatus for the manufacture of expanded plastics materials |
US4221948A (en) * | 1976-11-17 | 1980-09-09 | Jean Olivier A L | Apparatus for subjecting a material to electromagnetic waves |
US4304974A (en) * | 1979-05-04 | 1981-12-08 | Matsushita Electric Industrial Co., Ltd. | Energy supply structure for combined resistance heater for H. F. heater oven |
US4326112A (en) * | 1977-10-14 | 1982-04-20 | Matsushita Electric Industrial Co., Ltd. | Microwave oven having a tubular L-shaped antenna |
US4329557A (en) * | 1979-12-07 | 1982-05-11 | General Electric Company | Microwave oven with improved energy distribution |
US4342896A (en) * | 1976-12-23 | 1982-08-03 | Raytheon Company | Radiating mode stirrer heating system |
US4410779A (en) * | 1978-04-03 | 1983-10-18 | Raytheon Company | Combination microwave oven control system |
US4937418A (en) * | 1988-06-07 | 1990-06-26 | Michel Boulard | Microwave oven fitted with a wave spreader |
WO2000017248A1 (en) * | 1998-09-22 | 2000-03-30 | Huntsman Ici Chemicals Llc | Process for making rigid polyurethane and polyisocyanurate foams |
US6211503B1 (en) * | 1998-09-29 | 2001-04-03 | Fraunhofer Gesellschaft Zur Forderung Der Angeandten Forschung E.V | Device and method of heating components made of microwave absorbing plastic |
WO2003009646A2 (en) * | 2001-07-20 | 2003-01-30 | American Purification, Inc. | Microwave desorber for removing contaminants from resin |
US20070257029A1 (en) * | 2006-05-02 | 2007-11-08 | Opperman Stephen H | Microwave heating system and method for removing volatiles from adsorbent materials |
EP2015014A1 (en) * | 2007-07-11 | 2009-01-14 | Bayer MaterialScience AG | Method for drying foams made of aqueous PUR dispersions |
US20100024851A1 (en) * | 2008-08-04 | 2010-02-04 | Rockwell Anthony L | Insulation Element For An Electrical Appliance Such As A Dishwasher |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2603741A (en) * | 1946-12-12 | 1952-07-15 | Goodrich Co B F | High-frequency heating |
US2738406A (en) * | 1951-09-20 | 1956-03-13 | Gen Precision Lab Inc | Radio frequency vulcanizing |
US2764516A (en) * | 1955-02-23 | 1956-09-25 | Goodyear Tire & Rubber | Method of forming laminated structures |
US2813185A (en) * | 1954-03-08 | 1957-11-12 | Raytheon Mfg Co | Heating devices |
US2841205A (en) * | 1955-07-13 | 1958-07-01 | Collins & Aikman Corp | Method of and apparatus for making polyurethane foam coated fabrics |
US2961520A (en) * | 1957-04-02 | 1960-11-22 | Gen Motors Corp | Domestic appliance |
GB864965A (en) * | 1958-03-27 | 1961-04-12 | Gen Motors Corp | Improved refrigerator cabinet, and method of making such a cabinet |
US3177333A (en) * | 1962-08-02 | 1965-04-06 | Tappan Co | Conveyor microwave oven |
US3209056A (en) * | 1962-10-30 | 1965-09-28 | Gen Motors Corp | Method of insulating refrigerator cabinets and other insulation spaces |
-
1963
- 1963-04-02 US US269975A patent/US3265780A/en not_active Expired - Lifetime
-
1964
- 1964-03-05 GB GB9328/64A patent/GB1032219A/en not_active Expired
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2603741A (en) * | 1946-12-12 | 1952-07-15 | Goodrich Co B F | High-frequency heating |
US2738406A (en) * | 1951-09-20 | 1956-03-13 | Gen Precision Lab Inc | Radio frequency vulcanizing |
US2813185A (en) * | 1954-03-08 | 1957-11-12 | Raytheon Mfg Co | Heating devices |
US2764516A (en) * | 1955-02-23 | 1956-09-25 | Goodyear Tire & Rubber | Method of forming laminated structures |
US2841205A (en) * | 1955-07-13 | 1958-07-01 | Collins & Aikman Corp | Method of and apparatus for making polyurethane foam coated fabrics |
US2961520A (en) * | 1957-04-02 | 1960-11-22 | Gen Motors Corp | Domestic appliance |
GB864965A (en) * | 1958-03-27 | 1961-04-12 | Gen Motors Corp | Improved refrigerator cabinet, and method of making such a cabinet |
US3177333A (en) * | 1962-08-02 | 1965-04-06 | Tappan Co | Conveyor microwave oven |
US3209056A (en) * | 1962-10-30 | 1965-09-28 | Gen Motors Corp | Method of insulating refrigerator cabinets and other insulation spaces |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3326787A (en) * | 1963-09-05 | 1967-06-20 | Gen Motors Corp | Method of manufacturing polyurethane foam using a gas to create sonic energy |
DE2622173A1 (en) * | 1975-05-19 | 1976-12-02 | Matsushita Electric Ind Co Ltd | DEVICE FOR HEATING AN OBJECT WITH HIGH FREQUENCY RADIATION, IN PARTICULAR MICROWAVE OVEN |
US4476362A (en) * | 1975-05-19 | 1984-10-09 | Matsushita Electric Industrial Co., Ltd. | High frequency heating apparatus |
US4086813A (en) * | 1975-12-22 | 1978-05-02 | General Electric Company | Microwave oven food temperature sensing probe assembly including a reflector |
US4173608A (en) * | 1976-10-22 | 1979-11-06 | Isobox-Barbier | Process and apparatus for the manufacture of expanded plastics materials |
US4221948A (en) * | 1976-11-17 | 1980-09-09 | Jean Olivier A L | Apparatus for subjecting a material to electromagnetic waves |
US4342896A (en) * | 1976-12-23 | 1982-08-03 | Raytheon Company | Radiating mode stirrer heating system |
US4144437A (en) * | 1977-07-29 | 1979-03-13 | Litton Systems, Inc. | Microwave oven energy stirrer |
US4326112A (en) * | 1977-10-14 | 1982-04-20 | Matsushita Electric Industrial Co., Ltd. | Microwave oven having a tubular L-shaped antenna |
US4410779A (en) * | 1978-04-03 | 1983-10-18 | Raytheon Company | Combination microwave oven control system |
US4304974A (en) * | 1979-05-04 | 1981-12-08 | Matsushita Electric Industrial Co., Ltd. | Energy supply structure for combined resistance heater for H. F. heater oven |
US4329557A (en) * | 1979-12-07 | 1982-05-11 | General Electric Company | Microwave oven with improved energy distribution |
US4937418A (en) * | 1988-06-07 | 1990-06-26 | Michel Boulard | Microwave oven fitted with a wave spreader |
WO2000017248A1 (en) * | 1998-09-22 | 2000-03-30 | Huntsman Ici Chemicals Llc | Process for making rigid polyurethane and polyisocyanurate foams |
US6211503B1 (en) * | 1998-09-29 | 2001-04-03 | Fraunhofer Gesellschaft Zur Forderung Der Angeandten Forschung E.V | Device and method of heating components made of microwave absorbing plastic |
WO2003009646A2 (en) * | 2001-07-20 | 2003-01-30 | American Purification, Inc. | Microwave desorber for removing contaminants from resin |
WO2003009646A3 (en) * | 2001-07-20 | 2003-10-23 | American Purification Inc | Microwave desorber for removing contaminants from resin |
US20070257029A1 (en) * | 2006-05-02 | 2007-11-08 | Opperman Stephen H | Microwave heating system and method for removing volatiles from adsorbent materials |
US7498548B2 (en) | 2006-05-02 | 2009-03-03 | Ranger Research, Inc. | Microwave heating system and method for removing volatiles from adsorbent materials |
EP2015014A1 (en) * | 2007-07-11 | 2009-01-14 | Bayer MaterialScience AG | Method for drying foams made of aqueous PUR dispersions |
WO2009007037A1 (en) * | 2007-07-11 | 2009-01-15 | Bayer Materialscience Ag | Method for the drying of foams composed of aqueous pu dispersions |
US20090018224A1 (en) * | 2007-07-11 | 2009-01-15 | Bayer Materialscience Ag | Process for the drying of foams composed of aqueous pu dispersions |
US20100024851A1 (en) * | 2008-08-04 | 2010-02-04 | Rockwell Anthony L | Insulation Element For An Electrical Appliance Such As A Dishwasher |
US8205287B2 (en) * | 2008-08-04 | 2012-06-26 | Owens Corning Intellectual Capital, Llc | Insulation element for an electrical appliance such as a dishwasher |
Also Published As
Publication number | Publication date |
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GB1032219A (en) | 1966-06-08 |
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