METHOD AND APPARATUS FOR JOINING COMPOSITE STRUCTURAL MEMBERS USING THERMAL SPREADER

• US 20100170613A1
• Filed: 03/16/2010
• Published: 07/08/2010
• Est. Priority Date: 11/13/2008
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Kendall, Jeffrey D., Kline, William T., Kennedy, Thomas J.
• Granted Patent: US 8,307,872 B2
• Time in Patent Office: Days
• US Class Current: 156/60
• CPC Class Codes: B29C 2043/3615 Forming elements, e.g. mandrels or rams or stampers or pistons or plungers or punching devices
• CPC Class Codes: B29C 2043/3649 Inflatable bladders using gas or fluid and related details
• CPC Class Codes: B29C 2043/5816 temperature
• CPC Class Codes: B29C 33/02 with incorporated heating or cooling means
• CPC Class Codes: B29C 33/30 Mounting, exchanging or centering moulds, mould parts or cores; B29C33/485 takes precedence
• CPC Class Codes: B29C 35/02 Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mouldcold vulcanisation B29C35/18 ; vulcanising tyres, presses therefor B29D30/0601
• CPC Class Codes: B29C 43/10 Isostatic pressing, i.e. using non-rigid pressure-exerting members against rigid parts or dies
• CPC Class Codes: B29C 43/3642 Bags, bleeder sheets or cauls for isostatic pressing
• CPC Class Codes: B29C 43/52 Heating or cooling
• CPC Class Codes: B29C 43/58 Measuring, controlling or regulating for bank adjustment in calendering B29C43/245
• CPC Class Codes: B29C 65/00 Joining or sealing of preformed parts , e.g. welding of plastics materials; Apparatus therefor general aspects of processes or apparatus for joining preformed parts B29C66/00; using porous material formed by internal pressure generated therein for joining preformed parts B29C44/1228, B29C44/326
• CPC Class Codes: B29C 65/18 using heated tools
• CPC Class Codes: B29C 65/26 Hot fluid
• CPC Class Codes: B29C 65/4835 Heat curing adhesives
• CPC Class Codes: B29C 65/5042 covering both elements to be joined
• CPC Class Codes: B29C 65/505 and placed in a recess formed in the parts to be joined, e.g. in order to obtain a continuous surface
• CPC Class Codes: B29C 65/5071 and being composed by one single element
• CPC Class Codes: B29C 65/5085 and comprising grooves, e.g. being E-shaped, H-shaped
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/1142 Single butt to butt joints
• CPC Class Codes: B29C 66/116 : Single bevelled joints, i.e. one of the parts to be joined being bevelled in the joint area
• CPC Class Codes: B29C 66/1162 : Single bevel to bevel joints, e.g. mitre joints
• CPC Class Codes: B29C 66/128 : Stepped joint cross-sections
• CPC Class Codes: B29C 66/14 : the joint having the same thickness as the thickness of the parts to be joined B29C66/1142 takes precedence
• CPC Class Codes: B29C 66/5241 : for forming coaxial connections, i.e. the profiled elements to be joined forming a zero angle relative to each other
• CPC Class Codes: B29C 66/5243 : for forming corner connections, e.g. for making window frames or V-shaped pieces welded corner joints for window frames E06B3/9604
• CPC Class Codes: B29C 66/63 : Internally supporting the article during joining B29C66/49 takes precedence
• CPC Class Codes: B29C 66/71 : characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/721 : Fibre-reinforced materials B29C66/729 takes precedence
• CPC Class Codes: B29C 66/7212 : characterised by the composition of the fibres
• CPC Class Codes: B29C 66/723 : being multi-layered B29C66/7292, B29C66/72941 take precedence
• CPC Class Codes: B29C 66/73941 : characterised by the materials of both parts being thermosets
• CPC Class Codes: B29C 66/81261 : Thermal properties, e.g. thermal conductivity, thermal expansion coefficient
• CPC Class Codes: B29C 66/81455 : being a fluid inflatable bag or bladder, a diaphragm or a vacuum bag for applying isostatic pressure inflatable element positioned between the joining tool and a backing-up part B29C66/82421
• CPC Class Codes: B29C 66/81811 : of the welding jaws
• CPC Class Codes: B29C 66/81831 : of the welding jaws
• CPC Class Codes: B29C 66/91212 : involving measurement means being part of the welding jaws, e.g. integrated in the welding jaws
• CPC Class Codes: B29C 66/91231 : of the joining tool
• CPC Class Codes: B29C 66/9141 : by controlling or regulating the temperature
• CPC Class Codes: B29C 66/91421 : of the joining tools
• CPC Class Codes: B29C 66/91443 : following a temperature-time profile B29C65/38 takes precedence
• CPC Class Codes: B29C 66/91631 : the heat or the thermal flux being kept constant over time
• CPC Class Codes: B29C 66/9192 : in explicit relation to another variable, e.g. temperature diagrams
• CPC Class Codes: B29C 66/91951 : in explicit relation to time, e.g. temperature-time diagrams
• CPC Class Codes: B29C 66/9221 : by measuring the pressure, the force or the mechanical power
• CPC Class Codes: B29C 66/9241 : by controlling or regulating the pressure, the force or the mechanical power
• CPC Class Codes: B29C 66/961 : involving a feedback loop mechanism, e.g. comparison with a desired value
• CPC Class Codes: B29C 70/44 : using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
• CPC Class Codes: B29K 2063/00 : Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/06 : containing reinforcements, fillers or inserts
• CPC Class Codes: B29K 2307/04 : Carbon
• CPC Class Codes: B29L 2031/003 : having a profiled transverse cross-section
• CPC Class Codes: B29L 2031/3085 : Wings
• CPC Class Codes: B32B 37/0046 : characterised by constructional aspects of the apparatus
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

An apparatus for forming a structural member includes a tool platform and a pressure platform that may be movable relative to one another between an open position and a closed position. The apparatus may include a tool against which the member may be pressed. The tool may be supported by the tool platform and may have an inner surface. The apparatus may include a pressure bladder configured to be pressurized for applying pressure to the member. The pressure bladder may be supported by the pressure platform for pressing the member against the tool. Also included may be a heating system for heating the tool and a tool liner in thermal contact with the inner surface for distributing heat thereto.

Claims

1. An apparatus for curing a structural member, comprising:

a tool platform and a pressure platform relatively movable between an open position and a closed position;

a tool against which the member may be pressed, the tool being supported by the tool platform and having an inner surface;

a pressure bladder configured to be pressurized for applying pressure to the member, the pressure bladder being supported by the pressure platform for pressing the member against the tool;

a heating system for heating the tool; and

a tool liner in thermal contact with the inner surface for distributing heat thereto.

2. The apparatus of claim 1 wherein:

the tool liner is formed of material having a relatively high thermal conductivity.

3. The apparatus of claim 1 wherein:

the tool liner comprises at least one of copper and aluminum sheet.

4. The apparatus of claim 1 wherein:

the tool liner has a thermal conductivity in the range of from approximately 200 W/mK to approximately 600 W/mK measured at 85°

C.

5. The apparatus of claim 1 wherein:

the tool liner is mechanically fastened to the mandrel.

6. The apparatus of claim 1 further comprising:

a thermally conductive film interposed between the tool liner and the inner surface.

7. The apparatus of claim 6 wherein:

the film comprises a thermal paste.

8. The apparatus of claim 1 further comprising:

a heat sink in thermal contact with a portion of the inner surface for transferring heat therefrom.

9. An apparatus for curing a composite structural member, comprising:

a tool platform and a pressure platform relatively movable between an open position and a closed position;

a mandrel against which the member may be pressed, the mandrel being supported by the tool platform and having an inner surface and including at least one end wall;

a pressure bladder configured to be pressurized for applying pressure to the member, the pressure bladder being supported by the pressure platform for pressing the member against the mandrel;

a heating system for heating the mandrel;

a copper sheet mechanically fastened to the inner surface and being in thermal contact therewith for distributing heat thereto;

a thermally conductive film interposed between the tool liner and the inner surface; and

a heat sink in thermal contact with a portion of the inner surface for transferring heat therefrom.

10. A heated tool assembly for forming a structural member, comprising:

a tool and a pressure bladder for mounting the structural member therebetween, the tool having an inner surface;

a liner in thermal contact with the inner surface of the tool;

a heating system for heating the tool, including;

a heater for heating a heated medium;

a blower for blowing the heated medium; and

a plurality of nozzles for directing the heated medium over the tool liner.

11. The heated tool assembly of claim 10 wherein:

the tool liner is formed of material having a relatively high thermal conductivity.

12. The heated tool assembly of claim 10 wherein:

the tool liner comprises at least one of copper and aluminum sheet.

13. The heated tool assembly of claim 10 wherein:

the tool liner has a thermal conductivity in the range of from approximately 200 W/mK to approximately 600 W/mK measured at 85°

C.

14. The heated tool assembly of claim 10 wherein:

the tool liner is mechanically fastened to the mandrel.

15. The heated tool assembly of claim 10 further comprising:

a thermally conductive film interposed between the tool liner and the inner surface.

16. The heated tool assembly of claim 15 wherein:

the film comprises a thermal paste.

17. The heated tool assembly of claim 10 further comprising:

a heat sink in thermal contact with a portion of the inner surface.

18. The heated tool assembly of claim 10 wherein:

the tool defines a plurality of zones;

the heating system further including a nozzle plenum assembly coupled between the blower and the nozzles for directing heated medium to the zones.

19. The heated tool assembly of claim 10 further comprising:

thermal insulation at least partially surrounding the pressure bladder for retaining heat in the structural member; and

at least one heater element interposed between the thermal insulation and the pressure bladder for heating the pressure bladder.

20. The heated tool assembly of claim 19 further comprising:

a bladder liner having a heater element mounted thereto for distributing heat to the pressure bladder.

21. A method of forming a structural member, comprising the steps of:

forming first and second composite sections;

forming a splice member;

providing a mandrel having inner and outer surfaces;

mounting a tool liner to the inner surface;

installing the first and second composite sections and the splice member between the outer surface and a pressure bladder; and

directing a heated medium onto the tool liner to heat the mandrel.

22. The method of claim 21 wherein the step of mounting the tool liner to the inner surface comprises:

mechanically fastening the tool liner to the inner surface.

23. The method of claim 21 further comprising the step of:

inserting a thermally conductive film between the tool liner and the inner surface.

24. The method of claim 21 wherein the mandrel includes a mandrel end wall, the method further comprising the step of:

mounting a heat sink on the inner surface adjacent to the mandrel end wall to reduce heating of the mandrel.

25. The method of claim 21 further comprising the step of:

pressurizing the pressure bladder while heating the mandrel.

26. A method of forming a composite structural member, comprising the steps of:

forming first and second composite sections;

forming a splice member;

providing a mandrel having inner and outer surfaces and at least one mandrel end wall;

mounting a tool liner to the inner surface;

installing a thermally conductive film between the tool liner and the inner surface;

mechanically fastening the tool liner to the inner surface;

mounting a heat sink to the inner surface adjacent to the mandrel end wall;

installing the first and second composite sections and the splice member between the outer surface and a pressure bladder;

directing a heated medium onto the tool liner to distribute heat across the outer surface;

transferring heat from the heat sinks to reduce heat input to the outer surface from the mandrel end walls;

pressurizing the pressure bladder while directing the heated medium onto the inner surface; and

curing the first and second composite sections and the splice member.