Diaphragm forming
A forming tool ( 100 ) for and a method of making a three dimensional composite component using double diaphragm forming. The forming tool ( 100 ) comprises a forming side having two or more regions of changing profile and one or more through holes associated with each region, the through holes exit on the forming side and are connectable to one or more vacuum sources such that vacuum can be selectively and discretely applied to each region.
1. An apparatus for producing a three dimensional composite component using a diaphragm forming process comprising a forming tool and two or more vacuum bags, wherein the forming tool comprises a forming side having two or more regions of changing profile and one or more through holes associated with each region, the through holes exiting on the forming side and being connectable to respective ones of the vacuum bags thereby to connect each respective vacuum bag with a corresponding one of the two or more regions of changing profile for vacuum supplied from one or more vacuum sources to be selectively and discretely applied to each region, wherein the through holes extend from a side of the tool that is opposite to the forming side and the opposite side includes two or more channels, wherein each channel is associated with a corresponding region of changing profile on the forming side and a one of the respective vacuum bags is received in each channel.
2. An apparatus according to claim 1 , wherein the one or more vacuum sources is attachable to the vacuum bags such that a vacuum can be selectively and discretely applied to each of the two or more regions of changing profile.
3. An apparatus according to claim 1 , wherein each respective vacuum bag for each region of changing profile is connected to a corresponding single vacuum device.
4. An apparatus according to claim 1 , wherein respective vacuum bags for respective regions of changing profile are connected in a group to a single vacuum device.
5. An apparatus according to claim 1 , wherein at least one vacuum pump provides the one or more vacuum sources.
6. An apparatus according to claim 1 , wherein the one or more vacuum sources comprise at least one pump connected to the two or more vacuum bags.
7. A method of producing a three dimensional composite component using diaphragm forming, wherein the method comprises the steps of:
applying a diaphragm pack containing composite material to the forming side of the forming tool of an apparatus according to claim 1 ;
connecting the through holes via the two or more vacuum bags to one or more vacuum sources;
applying heat to the diaphragm pack;
applying a vacuum selectively and discretely to each of the two or more regions between the diaphragm pack and the forming tool such that a region of the diaphragm pack to which vacuum is applied is drawn into contact with the forming side of the forming tool in a predetermined sequence to form a three dimensional component.
8. A method according to claim 7 , wherein the vacuum is applied to the regions of changing profile in sequence from the centre of the forming tool towards the periphery of the forming tool.