Thermoset bonding agent for non-distortion joining of selfsupporting thermoset component parts

Claim 1

A thermal adhesive bonding method for joining of plastic elements (2, 3) subject to further subsequent working and subject to distortion in the presence of minimum distortion related temperature at which the mass is distorted directly or under said subsequent working, comprising: forming an uncured thermosetting adhesive (7,8) adapted to bond to said elements (2, 3) and having a cure characteristic accelerated by heat and having integral means responsive to an externally generated energy field (12) to create heat within the adhesive (7, 8), applying said adhesive mixture (7) between the elements (2, 3) to be bonded in a thickness at least equal to 0.005 inch thick to form an intimate engaging coating to the elements (2,3), applying a compression force (15) across said elements (2,3) to maintain the spacing therebetween equal to at least 0.005 inches and less than 0.2 inches and to eliminate air pockets within the bond area and adhesive, generating said energy field (12) through the elements (2,3) and said adhesive (7,8) to activate the adhesive and generate heat within the adhesive (7,8) and timing said field (12) to create a heat history inclusive of limiting the increase in temperature in the mass of the rigid plastic elements (2,3) to substantially less than the total mass in the bond area and to a temperature less than the distortion related temperature, and subjecting said elements (2,3) to subsequent working substantially upon removal of said energy fields (12).

Claim 19

A method of bonding rigid thermoset elements (2,3) formed of a sheet molded compound with a thermoset heat activatable curing adhesive (7,8) along a selected interface with the elements (2, 3) having relatively thin projecting portions (5,6) extending from said interface area, said thermoset elements (2,3) being self-supporting and being subject to thermal distortion in response to heating of such elements (2,3) to the curing temperature of the adhesive (7,8) over an extended period, comprising: aligning first and second rigid self-supporting elements (2,3) of a sheet molded compound, mixing said adhesive (7,8) with particles (9) responsive to an energy field (12) for generating heat in response to an energy field (12), interposing a mass of said heat activatable curable adhesive (7,8) between said rigid self-supporting elements (2,3; 5,6) throughout said bonding interface, holding said elements (2,3) in intimate engagement with said adhesive (7,8) under pressure (15) to precisely locate and preset the thickness of said adhesive (7,8), subjecting said elements (2,3) and adhesives (7,8) to an energy field (12) throughout said bonding area to rapidly raise the temperature of essentially only said adhesive (7,8) to the curing temperature and holding said adhesive (7,8) at least at said curing temperature for a maximum time period to cure the adhesive (7,8) and establishing a heat time history level insufficient to heat significant mass of the elements (2,3) adjacent the bond area to destroy the rigid self-supporting character of said elements (2,3) and to hereby maintain the integrity of the elements (2,3).

Claim 20

A method of bonding rigid thermoset elements (2,3) formed of a sheet molded compound with a thermoset heat activatable curing adhesive (7,8) along a selected interface with the elements (2, 3) having relatively thin projecting portions (5,6) extending from said interface area, said thermoset elements (2,3) being self-supporting and being subject to thermal distortion in response to heating of such elements (2,3) to the curing temperature of the adhesive (7,8) over an extended period, comprising: aligning first and second rigid self-supporting elements (2,3) of a sheet molded compound, mixing said adhesive (7,8) with particles (9) responsive to an energy field (12) for generating heat in response to an energy field (12), interposing a mass of said heat activatable curable adhesive (7,8) between said rigid self-supporting elements (2,3; 5,6) throughout said bonding interface, holding said elements (2,3) in intimate engagement with said adhesive (7,8) under pressure (15) to precisely locate and preset the thickness of said adhesive (7,8), subjecting said elements (2,3) and adhesives (7,8) to an energy field (12) throughout said bonding area to rapidly raise the temperature of essentially only said adhesive (7,8) to the curing temperature and holding said adhesive (7,8) at least at said curing temperature for a maximum time period to cure the adhesive (7,8) and establishing a heat time history level insufficient to heat significant mass of the elements (2,3) adjacent the bond area to destroy the rigid self-supporting character of said elements (2,3) and to hereby maintain the integrity of the elements (2,3).

Claim 21

A method for accelerated curing of thermosetting adhesive (7,8) to join two or more selected areas of one or more component parts in a gel state comprising: selecting an uncured thermosetting type adhesive (8) having the ability to firmly adhere to the selected components and curing at an accelerated temperature of said adhesive above room temperature; mixing said uncured adhesive (8) and a particulate material (9) selected from the family of magnetic iron oxides including gamma Fe 2 0 3 and magnetic Fe 3 0 4 in a concentration sufficient to raise the temperature of said mixture (7) above room temperature and to substantially decrease the curing time relative to room temperature curing time and below a temperature which reduces the required physical properties of said adhesive, applying said mixture (7,17) to a component area to be bonded so as to form a coating one face of which is in contact with said area and in a thickness great enough to fill the desired lateral extent of bond area with an adhesive layer at least 0.005 inch thick when the following step is performed, placing a second component area in contact with a second face of said coating and squeezing the area against said coat (7,17) with only sufficient pressure to establish said areas separated by an adhesive thickness of between 0.005 inch and 0.200 inch so as to retain sufficient mass of such iron oxide of said adhesive mixture (7) in place between said areas to generate the operative heat to achieve an accelerated cure to assist the removal of intermediate air pockets and to squeeze out excess adhesive (26) from between the areas, and placing a source of high frequency magnetic field (12) in close enough relationship to said adhesive layer (7) to cause said heat to be generated in said magnetic iron oxide particles (9), energizing said magnetic field (12) for a period of time sufficiently long to cause the temperature of the adhesive layer (7) to raise the temperature required to accelerate cure and to hold such temperature for the time required to cure said adhesive to a state permitting production handling without disrupting the relative position of said surfaces, but a time short enough to restrict the mass of substrate material heated to curing temperature to substantially less than the mass heated by prior art external-heat-source methods, and removing the cured adhesive layer (7) from the proximity of the high frequency energy source (10,11) within the time period substantially less than the cure time for unmodified adhesive at room temperature.

Claim 22

A method for accelerated curing of thermosetting adhesive (7,8) to join two or more selected areas of one or more component parts in a gel state comprising: selecting an uncured thermosetting type adhesive (8) having the ability to firmly adhere to the selected components and curing at an accelerated temperature of said adhesive above room temperature; mixing said uncured adhesive (8) and a particulate material (9) selected from the family of magnetic iron oxides including gamma Fe 2 0 3 and magnetic Fe 3 0 4 in a concentration sufficient to raise the temperature of said mixture (7) above room temperature and to substantially decrease the curing time relative to room temperature curing time and below a temperature which reduces the required physical properties of said adhesive, applying said mixture (7,17) to a component area to be bonded so as to form a coating one face of which is in contact with said area and in a thickness great enough to fill the desired lateral extent of bond area with an adhesive layer at least 0.005 inch thick when the following step is performed, placing a second component area in contact with a second face of said coating and squeezing the area against said coat (7,17) with only sufficient pressure to establish said areas separated by an adhesive thickness of between 0.005 inch and 0.200 inch so as to retain sufficient mass of such iron oxide of said adhesive mixture (7) in place between said areas to generate the operative heat to achieve an accelerated cure to assist the removal of intermediate air pockets and to squeeze out excess adhesive (26) from between the areas, and placing a source of high frequency magnetic field (12) in close enough relationship to said adhesive layer (7) to cause said heat to be generated in said magnetic iron oxide particles (9), energizing said magnetic field (12) for a period of time sufficiently long to cause the temperature of the adhesive layer (7) to raise the temperature required to accelerate cure and to hold such temperature for the time required to cure said adhesive to a state permitting production handling without disrupting the relative position of said surfaces, but a time short enough to restrict the mass of substrate material heated to curing temperature to substantially less than the mass heated by prior art external-heat-source methods, and removing the cured adhesive layer (7) from the proximity of the high frequency energy source (10,11) within the time period substantially less than the cure time for unmodified adhesive at room temperature.