Method for manufacturing slide-room for recreational vehicle

Abstract

A slide-room for installation in a recreational vehicle includes a shell, which can be constructed from fiberglass. The shell has an end wall, a ceiling, a floor, two opposing side walls, and a flange extending from the end wall, wherein the end wall, the ceiling, the floor, the side walls and the flange have a one-piece, unitary construction. The shell for a slide-room can be formed from fiberglass using a vacuum-assisted resin transfer process. During the vacuum-assisted resin transfer process, a mold apparatus can include a perimeter seal system to inhibit resin from flowing into spaces between mating components of the mold. The perimeter seal system can include clamp seal assemblies and/or vacuum seal assemblies.

We claim: 
     
         1 . A mandrel for use in molding a composite part, comprising:
 a side surface and a lower surface, the side surface and the lower surface having a common edge; and   a vacuum seal arrangement located along the lower surface and the side surface of the mandrel, the vacuum seal arrangement extending from the side surface to the lower surface across the common edge and defining a bounded area on the side surface and the lower surface that is continuous across the common edge, the vacuum seal arrangement being configured such that a portion of the lower surface is within the bounded area and a portion of the lower surface is outside the bounded area.   
     
     
         2 . The mandrel of  claim 1 , wherein the mandrel is configured such that when the mandrel is positioned on a base surface with the seal arrangement contacting the base surface and contacting an adjacent mandrel, the vacuum seal arrangement defines a vacuum chamber that at least partially encloses the bounded area. 
     
     
         3 . The mandrel of  claim 1 , wherein the seal arrangement is configured such that when the mandrel is positioned on a base surface the seal arrangement spaces the lower surface of the mandrel above the base surface, and the portion of the lower surface that is outside the bounded area defines a recess configured to receive an edge portion of a preform. 
     
     
         4 . The mandrel of  claim 1 , wherein the vacuum seal arrangement comprises a first seal located along the lower surface and the side surface of the mandrel, and a second seal located along the lower surface and the side surface of the mandrel. 
     
     
         5 . The mandrel of  claim 4 , wherein the first and second seals intersect one another at an end portion of the side surface opposite the common edge. 
     
     
         6 . The mandrel of  claim 4 , wherein the first seal comprises a flap seal. 
     
     
         7 . The mandrel of  claim 1 , wherein the vacuum seal arrangement comprises:
 a first seal and a second seal, the second seal being spaced apart from the first seal, the first and second seals extending along a length of the lower surface; and   a third seal and a fourth seal, the fourth seal being spaced apart from the third seal, the third and fourth seals extending along a length of the side surface;   wherein the first seal and the third seal, and the second seal and the fourth seal, respectively, intersect one another at the common edge of the lower surface and the side surface of the mandrel.   
     
     
         7 . The mandrel of  claim 1 , wherein the mandrel comprises at least one vacuum port in communication with the bounded area. 
     
     
         8 . The mandrel of  claim 1 , wherein the portion of the lower surface outside the bounded area comprises a fluid port configured to supply a resin to the portion of the lower surface outside the bounded area. 
     
     
         9 . A molding apparatus for molding composite parts, comprising:
 a plurality of mandrels, each mandrel having first and second side surfaces and a lower surface, wherein the mandrels are arranged such that the first side surface of each respective mandrel opposes the second side surface of the adjacent mandrel;   a base tool having an upper surface on which the plurality of mandrels are arranged, the mandrels and base tool together defining an interior compartment with an opening above; and   a vacuum seal arrangement located along the lower surface and the first side surface of each mandrel, the vacuum seal arrangement of each mandrel extending across a common edge between the lower surface and the first side surface of each mandrel and defining a bounded area on the first side surface and the lower surface that is continuous across the common edge of each mandrel, the vacuum seal arrangements being configured such that a portion of the lower surface of each mandrel is within the bounded area and a portion of the lower surface of each mandrel is outside the bounded area;   wherein the vacuum seal arrangements, the lower surfaces of the mandrels, and the upper surface of the base tool collectively define a vacuum chamber between the lower surfaces of the mandrels and the upper surface of the base tool that is continuous around a perimeter of the interior compartment;   wherein the vacuum seal arrangements, the first side surfaces, and the second side surfaces of respective adjacent mandrels each define a respective vacuum chamber wherever the first and second side surfaces of respective adjacent mandrels are opposed; and   wherein the vacuum chamber between the lower surfaces of the mandrel and the upper surface of the base tool is fluidly connected to each of the respective vacuum chambers between opposed side surfaces of adjacent mandrels.   
     
     
         10 . The molding apparatus of  claim 9 , wherein at least one of the mandrels comprises a vacuum port in communication with the vacuum chambers. 
     
     
         11 . The molding apparatus of  claim 9 , wherein the seal arrangement of each mandrel comprises first and second spaced apart seals extending along a length of the lower surface, wherein ends of the first and second seals contact adjacent ends of first and second seals of an adjacent mandrel. 
     
     
         12 . The molding apparatus of  claim 11 , wherein each mandrel comprises third and fourth seals on one of the first or second side surfaces, the third and fourth seals having respective lower ends that contact respective ends of the first and second seals on the lower surface of the same mandrel. 
     
     
         13 . The molding apparatus of  claim 9 , wherein the base tool is configured to support at least two molding assemblies at one time. 
     
     
         14 . The molding apparatus of  claim 9 , wherein:
 the first side surfaces of the mandrels comprise at least one alignment pin;   the second side surfaces of the mandrels comprise at least one pin-receiving recess; and   the alignment pin of each mandrel is received in a recess of an adjacent mandrel.   
     
     
         15 . The molding apparatus of  claim 9 , further comprising at least one bracket positionable along the length of the base tool, the bracket comprising at least one alignment element configured to mate with a corresponding alignment element on one of the mandrels. 
     
     
         16 . A method for forming a fiberglass part, comprising:
 positioning a plurality of mandrels on a base tool, each mandrel having a lower surface and a side surface, the base tool having an upper surface on which the plurality of mandrels are arranged, the mandrels and base tool together defining an interior compartment with an opening above;   positioning a vacuum seal assembly wherever two mandrel surfaces are opposed and wherever a mandrel surface is supported by the base tool such that each of the vacuum seal assemblies are in fluid communication with each other and form a continuous vacuum chamber, such that each of the vacuum seal assemblies extend across a common edge between the lower surface and the side surface of the respective mandrel and define a bounded area on the side surface and the lower surface that is continuous across the common edge, and such that a portion of the lower surface of each mandrel is within the bounded area and a portion of the lower surface is outside the bounded area;   positioning a fiberglass preform in the interior compartment;   positioning an infusion bag in the interior compartment over the fiberglass preform;   introducing a resin into the mold so that it flows over and through the preform; and   allowing the resin to cure to form a fiberglass part.   
     
     
         17 . The method of  claim 16  further comprising:
 establishing a first vacuum in the continuous vacuum chamber; and 
 establishing a second vacuum in the space occupied by the preform; 
 wherein the pressure of the first vacuum is lower than the pressure of the second vacuum. 
 
     
     
         18 . The method of  claim 16 , further comprising clamping surfaces of opposed mandrels to facilitate sealing. 
     
     
         19 . The method of  claim 16 , wherein positioning the plurality of mandrels further comprises mounting one or more of the plurality of mandrels on one or more brackets supported by the base tool such that the plurality of mandrels are maintained in a substantially rectangular arrangement. 
     
     
         20 . The method of  claim 16 , further comprising
 creating a space between the lower surfaces of the mandrels and the upper surface of the base tool in which an edge portion of the preform is located.