System and method of forming an injection-bonded joint
A method of forming an injection-bonded joint may include forming a chamber wall within a bondline region between mating surfaces of a first part and a second part. The chamber wall may divide a bondline length and define at least one adhesive chamber. The method may include injecting a structural adhesive into the adhesive chamber through an injection port, and discharging excess adhesive from the adhesive chamber through a bleed hole.
1. A method of forming an injection-bonded joint, comprising the steps of:
providing a first part having opposing inner and outer surfaces, and a second part having a cross-section comprising a C-channel;
inserting a circumferential or planar edge of the first part into the C-channel;
forming a chamber wall within a bondline region between mating opposing surfaces of the first part and the C-channel of the second part, the chamber wall dividing a bondline length and defining at least one adhesive chamber;
forming a bondline dam along an upper edge of the C-channel on each opposing inner and outer surface of the first part, the chamber wall, the bondline dam, and the mating surfaces collectively enclosing the adhesive chamber;
injecting a structural adhesive into each adhesive chamber through an injection port formed in the second part;
discharging excess structural adhesive from each adhesive chamber through a bleed hole located between the first and second parts and formed within the bondline dam of the adhesive chamber; and
collecting the excess structural adhesive in an adhesive reservoir fluidly coupled to each bleed hole, each adhesive reservoir being formed as one of a vertical column comprising a longitudinally-extending channel attached to the outer surface of the first part and an outwardly projecting shelf attached to an outer surface of the second part.
2. The method of claim 1 , wherein the step of forming the chamber wall comprises:
forming the chamber wall from adhesive.
3. The method of claim 1 , wherein the step of forming the chamber wall comprises:
including a bond wire in the chamber wall.
4. The method of claim 1 , wherein the bondline length is at least twice a bondline width.
5. The method of claim 1 , wherein the injection port is located proximate a chamber wall.
6. The method of claim 1 , wherein the injection port is located proximate a lower edge of the adhesive chamber.
7. The method of claim 1 , wherein the bleed hole and the injection port are located at opposite chamber ends of the adhesive chamber.
8. The method of claim 1 , wherein:
a large bleed hole and a small bleed hole are located at opposing chambers ends of the adhesive chamber; and
the injection port being located proximate a chamber end having the small bleed hole.
9. The method of claim 1 , wherein the first part comprises a cylinder, the second part comprising an end ring having a cross-section configured as a C-channel, the step of forming the chamber wall comprising:
attaching a series of bond wires along a cylinder edge such that the bond wires divide the bondline length;
coating the bond wires with chamber wall adhesive; and
inserting a cylinder edge into the C-channel.
10. A method of forming an injection-bonded joint, comprising the steps of:
providing a first part having opposing inner and outer surfaces, and a second part having a cross-section comprising a C-channel;
inserting a circumferential or planar edge of the first part into the C-channel;
forming a series of chamber walls between mating opposing surfaces of the first part and the C-channel of the second part, the chamber walls dividing a bondline length into a plurality of adhesive chambers;
forming bondline dams along an upper edge of the C-channel on each opposing inner and outer surface of the first part, the chamber walls, the bondline dams, and the mating surfaces collectively enclosing the adhesive chambers;
injecting a structural adhesive into each of the adhesive chambers through an injection port formed in the second part;
discharging excess structural adhesive from each of the adhesive chambers through at least one bleed hole located in the bondline dams between the first and second part at a bondline perimeter of the adhesive chamber; and
collecting the excess structural adhesive in adhesive reservoirs fluidly coupled to the bleed holes, each adhesive reservoir being formed as one of a vertical column comprising a longitudinally-extending channel attached to the outer surface of the first part and an outwardly projecting shelf attached to an outer surface of the second part.
11. A structural assembly, comprising:
a first part having opposing inner and outer surfaces, and a second part having a cross-section comprising a C-channel, a circumferential or planar edge of the first part being inserted into the C-channel, and opposing mating surfaces of the first part and the C-channel of the second part being adhesively bonded together along a bondline region having a bondline length;
a series of chamber walls formed along the bondline length and dividing the bondline length into a plurality of adhesive chambers;
a bondline dam formed along an upper edge of the C-channel on each opposing inner and outer surface of the first part, the chamber wall, the bondline dam, and the mating surfaces collectively enclosing the adhesive chambers;
a structural adhesive injected into the adhesive chambers through at least one injection port formed in the second part, and excess structural adhesive being discharged from a bleed hole located between the first and second parts and formed within the bondline dam of each of the adhesive chambers; and
a plurality of adhesive reservoirs, each attached to an outer surface of one of the first and second parts and fluidly coupled to a respective one of the bleed holes for collecting the excess structural adhesive, each adhesive reservoir being formed as one of a vertical column comprising a longitudinally-extending channel attached to the outer surface of the first part and an outwardly projecting shelf attached to an outer surface of the second part.
12. The structural assembly of claim 11 , wherein:
the chamber walls are oriented generally transverse to the bondline length.
13. The structural assembly of claim 11 , further comprising:
a bond wire included with at least one of the chamber walls.
14. The structural assembly of claim 13 , wherein:
the bond wire defines a bondline thickness between the mating surfaces.
15. The structural assembly of claim 11 , wherein:
the structural adhesive comprises an epoxy adhesive.
16. The structural assembly of claim 11 , further comprising:
at least one mechanical fastener extending through the first part and the second part in the bondline region.
17. The structural assembly of claim 11 , wherein:
the first part and the second part define a substantially straight, planar bondline region.
18. The structural assembly of claim 11 , wherein:
the first part comprises a cylinder having a cylinder edge;
the second part comprising an end ring having a cross-section configured as a C-channel; and
the series of chamber walls being distributed around a cylinder circumference to form the plurality of the adhesive chambers bonding the cylinder edge to the C-channel.
19. The structural assembly of claim 11 , wherein:
the first part is formed of fiber-reinforced polymer matrix material; and
the second part is formed of metallic material.
20. The structural assembly of claim 11 , wherein the bondline length is at least twice a bondline width.