GB2571435A

GB2571435A - Integrated composite hybrid shock tower

Info

Publication number: GB2571435A
Application number: GB1900233.6A
Authority: GB
Inventors: Cao Yang; Ghevarchand Bedmutha Pankaj; Moreau-Gentien Louis
Original assignee: Faurecia Emissions Control Technologies USA LLC
Current assignee: Faurecia Emissions Control Technologies USA LLC
Priority date: 2018-01-09
Filing date: 2019-01-08
Publication date: 2019-08-28
Anticipated expiration: 2039-01-08
Also published as: FR3091514A1; GB201900233D0; CN110014796B; GB2571435B; CN110014796A; FR3091514B1

Abstract

A single-piece shock tower assembly 18, comprising a polymer-composite body 24, and a reinforcement member or wheel cover 26, overmoulded into the body 24. The body 24 is either a metal or a continuous fibre reinforced polymer composite material; and the reinforcement member may be a continuous fibre reinforced polymer composite, or a metal plate/bracket for mounting the body 24 to a fixed vehicle structure (20, Fig. 1A). The invention also includes a method of forming such a shock tower assembly 18, comprising: creating at least one reinforcement member from continuous fibere reinforced thermoplastic; surrounding a portion of the reinforcement member with a polymer composite material to form a shock tower body 24; and integrally moulding the reinforcement member with the shock tower body 24.

Description

INTEGRATED COMPOSITE HYBRID SHOCK TOWER

TECHNICAL FIELD

The subject invention relates to a shock tower and wheel cover and/or reinforcement member that are integrated together and formed from polymer composite material as single piece component to provide a hybrid shock tower configuration.

BACKGROUND OF THE INVENTION

Vehicles utilize many different suspension systems and components to absorb vibrations from road load inputs to improve vehicle control and passenger comfort. One such suspension component is a shock tower that is used to facilitate mounting of a damping component between a vehicle fixed structure and a suspension component for a vehicle wheel. Traditionally, shock towers have been formed from stamped steel components that are welded together to form a final assembly. These steel shock towers are heavy, time consuming to assemble, and adversely affect fuel economy. Die cast aluminum and magnesium shock towers provide for weight savings over traditional steel shock towers; however, these solutions have a cost premium that is only suitable for certain applications.

SUMMARY OF THE INVENTION

In one exemplary embodiment, a shock tower assembly includes a shock tower body comprised of a polymer composite material and a wheel cover integrated into the shock tower body and/or at least one reinforcement member integrated into the shock tower body at a first overmold interface to form a single-piece component. The at least one reinforcement member is comprised of at least one of a metal and a continuous fiber reinforced polymer composite material.

In another exemplary embodiment, a method of forming a shock tower assembly includes: (a) forming at least one reinforcement member from continuous fiber reinforced thermoplastic; (b) surrounding a first portion of the reinforcement member with a polymer composite material to form a shock tower body; and (c) integrally molding the reinforcement member with the shock tower body to form a single-piece component, wherein the single-piece component comprises the shock tower body with an overmolded portion at the first portion of the reinforcement member and including a second portion of the reinforcement member extending outwardly from the shock tower body.

In a further embodiment of any of the above, step (a) includes thermoforming the reinforcement member from a continuous fiber reinforced thermoplastic sheet to a predetermined shape.

In a further embodiment of any of the above, at least one attachment feature is formed at the overmolded portion of the reinforcement member.

In a further embodiment of any of the above, the reinforcement member comprises a bracket, cap, flange, or plate, and wherein the at least one attachment feature comprises at least one hole, spacer, and/or fastener.

In a further embodiment of any of the above, at least one attachment feature is formed at the second portion of the reinforcement member, wherein the at least one attachment feature is configured to attach the shock tower assembly to a vehicle structure.

In a further embodiment of any of the above, the method includes integrally molding a wheel cover comprised of the polymer composite material with the shock tower body to form the single-piece component.

In a further embodiment of any of the above, step (a) further includes forming the at least one reinforcement member as a bracket that has a load bearing portion and an overmolded portion, and wherein step (b) further includes placing the bracket in an injection tool and injecting a polymer composite material into the injection tool to surround the overmolded portion of the bracket; and wherein step (c) further includes removing a finished component from the injection tool, wherein the finished component comprises the load bearing portion of the bracket extending outwardly from the finished component and the overmolded portion of the bracket that is surrounded by the polymer composite material.

In a further embodiment of any of the above, the method includes trimming the bracket and forming at least one attachment feature at the overmolded portion of the bracket prior to step (b), and/or including trimming the bracket and forming at least one attachment feature at the load bearing portion of the bracket prior to step (b).

In a further embodiment of any of the above, the at least one attachment feature is formed at the overmolded portion of the bracket, and wherein the attachment feature comprises at least one hole to facilitate mechanical bonding with the polymer composite material during injection molding, and/or wherein the attachment feature comprises at least one flange to facilitate mechanical bonding with the polymer composite material during injection molding.

In a further embodiment of any of the above, the at least one attachment feature is formed at the load bearing portion of the bracket, and at least one location feature is formed in the injection tool for the bracket and further including, during step (b), inserting the load bearing portion of the bracket into the location feature such that the attachment feature is protected from the polymer composite material during injection molding, and applying pressure to opposing sides of the bracket to hold the bracket in place.

In a further embodiment of any of the above, the location feature comprises a groove and wherein the attachment feature comprises at least one hole, and including inserting the load bearing portion of the bracket into the groove to position the bracket in the injection tool.

In a further embodiment of any of the above, the method includes using at least a first slide to apply pressure against a first side of the bracket and a second slide to apply pressure against a second side of the bracket opposite the first side such that the bracket is securely clamped between the first and second slides during injection of the polymer composite material to prevent the bracket from moving and to isolate the bracket from polymer composite material.

In a further embodiment of any of the above, the at least one reinforcement member comprises at least one metal plate or bracket that is configured to mount the shock tower body to a fixed vehicle structure.

In a further embodiment of any of the above, the at least one reinforcement member comprises at least one mount structure comprised of continuous fiber reinforced polymer composite material.

In a further embodiment of any of the above, the at least one mount structure comprises a shock tower cap configured to receive a strut component, and/or wherein the at least one mount structure comprises a suspension control arm mount flange.

In a further embodiment of any of the above, the at least one reinforcement member comprises at least one metal plate and at least one mount structure comprised of continuous fiber reinforced polymer composite material, and optionally, wherein the at least one metal plate is configured to mount the shock tower body to a fixed vehicle structure and the at least one mount structure comprises a suspension control arm mount flange and/or a shock tower cap configured to receive a strut component.

In a further embodiment of any of the above, the first overmold interface is between the shock tower body and the at least one metal plate and including a second overmold interface between the at least one mount structure and the shock tower body.

In a further embodiment of any of the above, a wheel cover comprised of a polymer composite material is integrated with the shock tower body to form the single-piece component.

In a further embodiment of any of the above, the at least one reinforcement member comprises at least one plate comprised of the metal material integrated into the shock tower body at the first overmold interface and at least one mount structure comprised of the continuous fiber reinforced polymer composite material integrated into the shock tower body at a second overmold interface, and optionally, including a third overmold interface that integrates at least one of a nut, fastener, and sleeve into the shock tower body.

In a further embodiment of any of the above, the at least one reinforcement member comprises at least one bracket composed of the continuous fiber reinforced polymer composite material, the bracket having a load bearing portion extending outwardly from the shock tower body and an overmolded portion that is attached to the shock tower body at the first overmold interface, and including at least one attachment feature formed in the load bearing portion of the bracket, wherein the attachment feature is configured to be attached to load bearing component, and optionally, wherein the at least one attachment feature comprises at least one of a hole and flange, and optionally, wherein the load bearing portion is free from polymer composite material.

These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1A is a schematic representation of a suspension assembly for a vehicle wheel.

Figure IB is an exploded view of a composite shock tower and a composite wheel cover as used in the suspension assembly of Figure 1 A.

Figure 2A is a perspective view of a composite shock tower and wheel cover integrally formed as a single piece component.

Figure 2B is a top view of the composite shock tower and wheel cover of Figure 2A.

Figure 2C is a side view of the composite shock tower and wheel cover of Figure 2A.

Figure 2D is a bottom view of the composite shock tower and wheel cover of Figure 2A.

Figure 3 is an enlarged view of reinforcement members overmolded into the shock tower body for attachment to a suspension control arm.

Figure 4A is an exploded view of a shock tower cap and mount features to be molded with the shock tower cap.

Figure 4B is an exploded view of the cap of Figure 4A and a cap mount area of the shock tower body.

Figure 4C is a perspective view of the components of Figure 4B molded together as the single piece component.

Figure 4D is a section view as identified in Figure 4C.

Figure 5A is an exploded view of a front mount flange and a mount feature to be molded with the front mount flange.

Figure 5B is an exploded view of the front mount flange of Figure 5A and a front flange mount area of the shock tower body that are molded together to form the single piece component

Figure 5C is a section view through the structure of Figure 5B.

Figure 6A is an exploded view of a rear mount flange and a mount feature to be molded with the rear mount flange.

Figure 6B is an exploded view of the rear mount flange of Figure 6A and a rear flange mount area of the shock tower body that are molded together to form the single piece component

Figure 6C is a section view through the structure of Figure 6B.

Figure 7A is an exploded view of reinforcement members and the shock tower body.

Figure 7B is a perspective view of the reinforcement members of Figure 7A integrally molded with the shock tower to form the single piece component and which further shows overmolded interfaces between the reinforcement members and shock tower body.

Figure 8A is an exploded view of mount members and the shock tower body.

Figure 8B is a section view of the mount members as overmolded into the shock tower body of Figure 8A.

Figures 9A-D disclose method steps for making a component with an overmolded CFRP bracket.

Figure 10 is a schematic representation of a component made from the method shown in Figures 9A-D.

DETAILED DESCRIPTION

Figure 1A provides a schematic representation of a suspension assembly 10 for a vehicle wheel 12 that is positioned within a wheel cover 14. A stmt 16, made of a spring 16a and a shock absorber 16b, is used to dampen road load inputs from the wheel 12 to facilitate vehicle control and improve passenger comfort. A shock tower 18 is used to facilitate mounting of the strut 16 to a fixed vehicle structure 20, such as a frame, chassis, body, etc. The shock tower 18 is also used to facilitate connection of the strut 16 to a suspension control arm 22 associated with the wheel

12. A wheel cover 14 is usually connected to strut 16 by mechanical fasteners or spot welding.

As shown in Figure IB, the shock tower 18 includes a shock tower body 24 and a wheel cover 26. The shock tower body 24 and the wheel cover 26 are integrally formed together as a single piece component as shown in Figures 2A-2D. The shock tower 18 comprises an integrated polymer composite hybrid shock tower. Polymer materials in the form of injection molding resin and continuous fiber reinforced thermoplastic (CFRP), for example, are used to reduce the overall weight of the shock tower 18. Additional components such as brackets, sleeves, washers, nuts, bolts, screws, etc. for example, can be overmolded into the shock tower 18 to further reduce cost and provide the hybrid configuration. This will be discussed in greater detail below.

As shown in Figures 2A-2D, shock tower body 24 and wheel cover 26 are both made of the same polymer composite material in a single process, which results in an integral, single piece component. In one example, an injection molding process is used to achieve the integration, which will be discussed in greater detail below. In one example, the shock tower body 24 has thickness varying from 2 mm to 8 mm depending on the design requirements for a specific vehicle application. The thickness of the wheel cover 26 can be similar to that of the shock tower body 24 or can also be varied as needed for specific applications.

In one example, the shock tower 18 includes at least one reinforcement member that is integrated into the shock tower body 24. In one example, the reinforcement member comprises one or more brackets or plates 30, 32, 34 that are molded with the shock tower body 24 as part of the single piece component. In one example, the plates 30, 32, 34 are comprised of a metal material and are overmolded at a first overmold interface 36 (Figures 2D and 7B) to form the hybrid configuration. In one example, the metal material comprises sheet metal or the same metal material as used for an associated body-in-white (BIW), which corresponds to the fixed vehicle structure 20 as shown in Figure IA for example. In one example, the plates 30, 32, 34 facilitate attachment of the shock tower 18 to the BIW.

In another example, the at least one reinforcement member comprises a shock tower cap 40 that is made of CFRP and overmolded with the shock tower body 24 at a second mold interface 42 (Figures 2D and 4C-4D). In another example, the at least one reinforcement member includes front 44 and rear 46 mount flanges that are made of CFRP and overmolded with the shock tower body 24 at a third mold interface 48 (Figures 2D, 5-B-C and 6B-C). The inclusion of the overmolded shock tower cap 40 and the front/rear mount flanges 44, 46 provides increased mechanical properties in desired areas, which in the examples shown, respectively interface with the strut 16 and the suspension control arm 22.

Also shown in Figure 2D is a plurality of ribs 50 formed in a specified ribbing pattern to increases the stiffness of the shock tower 18 in desired areas. Various forms of ribbing patterns such as square, rectangular, X-shape, honey comb or circular can be employed in the shock tower body 24 or wheel cover 26 to stiffen the shock tower 18. It is possible to form the rib patterns in any desired number/pattern via the injection molding process.

One or more mounting holes 52 may also formed in the shock tower cap 40 and shock tower body 24 to provide a mount interface for the strut 16. Additionally, the shock tower 18 may include one or more additional mounting holes 54 that provide an interface for assembly of the shock tower 18 with other elements of the vehicle.

Figure 3 shows a magnified view of an interface of the front 44 and rear 46 mount flanges that are overmolded with the shock tower body 24 and that cooperate with the suspension control arm 22. The control arm 22 is attached with fasteners that pass through openings 56 where one fastener tightens into a corresponding opening 58 on the left of Figure 3 and another fastener tightens into a corresponding opening 60 on the right. The shock tower body 24 includes slot or sleeve portions 62 that receive respective ends of the front 44 and rear 46 mount flanges. These sleeve portions 62 include walls that are overmolded to engage opposing sides of the front 44 and rear 46 mount flanges at the overmold interface 48.

An outer facing wall 64 includes a slot or opening 66 to allow the fasteners to respectively pass through toward the openings 58, 60. An inner facing wall 68 includes a flat area 70 that provides a seat for a head of the fastener and one or more arms 72 that attach the flat area 70 to the wall 68. Additional strut or rib structures 74 are present around the overmolded sleeve portions 62 to transfer the loads to the main shock tower body 24 and to increase the mechanical properties of the attachment interface.

Figures 4A-D illustrates the shock tower cap 40, which transfers the load from the strut 16 to the shock tower 18 via direct contact and fasteners that pass through the openings 52. In one example, the cap 40 can be made of either CFRP or sheet metal, thermoformed or stamped before injection overmolding. Optionally, the cap 40 can be directly formed with a one shot process (forming and injecting). The cap 40 has ring shaped body with an opening 76 at a center of the cap 40 to receive a head of the strut 16 and/or any sensor or electronic device wire harness associated therewith. In one example, the cap 40 includes an outer flange 78 that extends about an outer periphery of the ring shaped body in a direction toward the shock tower body 24 to increase the stiffness and transfer the load to a shock tower vertical wall 80.

The shock tower vertical wall 80 extends upwardly to an upper cap portion that is molded around the cap 40. In one example, the upper cap portion area includes a peripheral recess 82 to receive an outer peripheral edge of the cap 40, and arms 84 that are molded around the cap 40. The arms 84 extend between the vertical wall 80 and a center ring 86 that includes an opening that aligns with the center opening 76 in the cap 40.

A plurality of ribs 88 are additionally provided at the top of the shock tower 18 to increase the strength and stiffness as needed. In one example, the strut 16 is mounted directly to the cap 40 and the holes 52 comprise three radially symmetrical holes that are drilled through the cap 40 to allow for the passage of fasteners. An additional hole 90 can be provided for positioning purposes.

In one example, additional mount features such as flanged bushings/compression limiters 92 are overmolded in the holes 52 during the injection molding process to keep metal-to-metal contact and transfer load from the strut 16 to the upper cap of the shock tower body 24. These flanged bushings/compression limiters 92 are required when polymer material is in a sandwiched relationship between a head of the fastener and the assembled strut 16 such that the thickness of the polymer material is not reduced over time due to creeping caused by the continuous force applied.

Figures 5A-5C show overmolding of the front mounting flange 44 with the shock tower body 24. In one example, the front mounting flange 44 is a separate component that is pre-manufactured prior to the injection molding process by thermoforming of CFRP sheets. The front mounting flange 44 is used to mount the control arm 22 as discussed above. The thickness of the front mounting flange 44 can range from 2 mm to 8 mm, for example, but can be varied depending on vehicle load requirements. In one example, metal bushings/compression limiters 94 are pressed into one or more holes 96 in the front mounting flange 44 to avoid direct contact of CFRP material with metal mounting fasteners for the same reasons of eliminating creep. The front mounting flange 44 is then overmolded during the injection molding process via the sleeve portions 62 as described above. The stiffening ribs 74 can be formed around the front mount flange to reinforce the attachment areas as needed. For the same reason, a metal spacer 98 with a nut 100 can be overmolded in the shock tower body 24 for control arm attachment.

Figures 6A-6C show overmolding of the rear mounting flange 46 with the shock tower body 24. In one example, the rear mounting flange 46 is a separate component that is pre-manufactured prior to the injection molding process by thermoforming of CFRP sheets. The rear mounting flange 46 is used to mount the control arm 22 as discussed above. The thickness of the rear mounting flange 46 can 9 range from 2 mm to 8 mm, for example, but can be varied depending on vehicle load requirements. In one example, metal bushings/compression limiters 94 are pressed into one or more holes 96 in the rear mounting flange 46 to avoid direct contact of CFRP material with metal mounting fasteners for the same reasons discussed above. The rear mounting flange 46 is then overmolded during the injection molding process via the sleeve portions 62 as described above. The stiffening ribs 74 can be formed around the rear mount flange to reinforce the attachment areas as needed. For the same reason, a metal spacer 98 with a nut 100 can be overmolded in the shock tower body 24 for control arm attachment.

Figures 7A-7B illustrate metal plates 30, 32, 34 overmolded into the shock tower 18 for assembly to the BIW. The plates 30, 32, 34 are used to facilitate the assembly of the shock tower 18 into the vehicle in compliance with existing resistance spot welding and fastener assembly processes. The metal plates 30, 32, 34 are formed to have at least one upper surface and one lower surface which will be in contact with surfaces of upper and lower tools. This is to ensure the positioning of the metal plates 30, 32, 34 and to prevent their movement during injection molding. These metal plates 30, 32, 34 may require surface treatment to avoid galvanic corrosion which is a standard practice for dissimilar material assembly into the BIW.

Figures 8A-8B illustrate the overmolding of additional attachment members 104 such as metal nuts for example, with the shock tower 18. These can be used to fasten other metallic parts on the shock tower with fasteners. In one example, all metallic parts are treated with a coating or made of stainless steel to avoid any galvanic corrosion due to the different electrode potential if the polymer composite material contains carbon fibers.

The subject invention uses polymer composite material, such as PA66 reinforced with discontinuous and continuous fiber, for example, to provide for improved mechanical performance in the shock tower 18, as well as a reduction of weight and cost as compared to current die cast designs, and without compromising mechanical performance requirements (NVH, pot hole load, durability, etc.) Additionally, the integration of the shock tower and wheel cover into a single part provides the benefits of lower part cost, elimination of sub-assembly steps, lower capital investment, and while also avoiding corrosion and part tearing.

The various rib formations, for example long running vertical and horizontal ribs in specified patterns, provide for connection of the shock tower at suspension attachment areas to BIW mount regions effectively reducing the risk of shock tower collapse and failure under load. The ribs can be patched to a large area effectively increasing the local stiffness with minimum use of material. Further, the overmolding of CFRP mount flanges enables the use of high performance material to meet the load requirements caused by the suspension system. Overmolding of the metal plates provides seamless assembly of shock tower to BIW using existing resistance spot welding and fastener assembly processes widely adopted in the automotive industry.

In another example configuration, a load bearing bracket 28 (Figure 2C) is overmolded as part of the shock tower 18. When replacing traditional die casted aluminum or magnesium shock towers with a polymer composite hybrid structure, some of the structural features cannot be reproduced through the use of direct injection of polymer composite material to form such structural features. For example, long load bearing brackets cannot be directly injection molded as part a shock tower due to issues such as injection length, risk of warping, draft angle, etc. The subject invention overmolds a bracket 30 formed from CFRP material as part of the shock tower. The use of CFRP enables the manufacture of long brackets inside an injected part which, as previously discussed, is not feasible by a traditional injection process. Further, the use of CFRP also has the advantage of providing the bracket 30 with higher load bearing capabilities.

A method of making a component 38 with the bracket 28 is shown in Figures 9A-D. As shown in Figure 9A, the bracket 30 is formed from CFRP and includes a load bearing portion 132. The bracket 28 is placed in an injection tool 134 that includes a bottom tool 134a and a top tool 134b that cooperate to enclose the bracket 28 within an internal cavity 136 (Figure 9B). A polymer composite material M is injected into the injection tool 34 to surround one end of the bracket 28 as shown in Figure 9C. The finished component 38 is removed from the injection tool 34 as shown in Figure 9D. The finished component 38 comprises a component body 140 that is molded around an overmolded portion 142 of the bracket 28 at an overmolding interface. The load bearing portion 132 of the bracket 28 projects outwardly from the component body 140 and is free from surrounding material.

In one example, the bracket 28 is thermoformed from an organo sheet to a predetermined shape. Once in the required shape, the bracket 28 can then be trimmed and drilled/machined to include one or more attachment features as needed.

In one example, the attachment feature comprises at least one attachment hole 144 that facilitates mechanical bonding with the polymer composite material during injection. In another example, the attachment feature comprises at least one flange 146 formed at one end of the bracket 30 to facilitate mechanical bonding with the polymer composite material during injection. Other types of attachment features could also be incorporated in the bracket 28 to interface with the polymer composite material during injection to increase bonding of the bracket 28 to the component body 140.

In one example, the bracket 28 is heated to improve adhesion during injection. A heat source 148, such as an electric heater or heating element for example, can be used to heat the bracket 28 before being placed into the tool 134 or during the injection process.

In one example, at least one attachment feature 150 is formed in the load bearing portion 132 of the bracket 28. The attachment feature 150 can comprise a mounting hole with or without a metallic insert, flange, etc. that is configured for attachment to a load bearing component. In one example, the attachment feature 150 is machined into the bracket 28 prior to being inserted into the tool 134.

In one example, at least one location feature 152 is made in the injection tool 134. The bracket 28 is inserted into the location feature 152 and pressure is applied to opposing sides of the bracket 28 to hold the bracket in place during injection. The load bearing portion 132 of the bracket 28 is inserted into the location feature 152 such that the attachment feature 150 is protected from the polymer composite material during injection. In one example, the location feature 152 comprises a groove and the attachment feature 150 comprises at least one hole.

In one example, a first slide 160 is used to apply pressure against a first side 162 of the bracket 28 and a second slide 164 is used to apply pressure against a second side 166 of the bracket 28, opposite the first side 162, such that the bracket 28 is securely clamped between the first 160 and second 164 slides during injection of the polymer composite material. The slides 160, 164 also keep the bracket 30 in place during closing of the tool 134 (Figure 9B). Further, the slides 160, 164 provide a sealing interface that prevents injected material from reaching the location feature 152 and the load bearing portion 132/attachment feature 150 of the bracket 28. The slides 160, 164 are then released to allow the finished component 38 to be removed from the tool 134 (Figure 9D).

In one example, the component body 140 defines a planar surface 170 that surrounds the bracket 28 at the overmold interface 142. The load bearing portion 132 of the bracket 28 extends outwardly away from the planar surface 170 to a second end 182 that is configured for attachment via at least one fastener 174 to a load bearing component 176 (Figure 10). In one example, the component body 140 is formed from the polymer composite material during the injection process.

Figure 10 shows a schematic representation of the component body 140 composed of the polymer composite material and which includes at least one bracket 28 composed of the CFRP material. The load bearing portion 132 extends outwardly from the component body 140 and the bracket 28 is attached to the component body 140 at the overmolded portion 142 of the bracket 28. The load bearing component 176 includes at attachment feature 178, such as a hole for example, that aligns with the hole of the attachment feature 150 formed in the bracket 28 and at least one fastener 174 secures the components together.

The bracket 28 extends from a first end 180 to the second end 182 to define a bracket length that can vary per various design parameters The bracket has a thickness defined between the opposing sides 162, 166 that is limited by the CFRP thermoforming process.

In one example, the overmolded portion 142 includes a transversely extending lip or flange 146 with the first end 80 that is overmolded with the polymer composite material. This further increases the attachment strength of the bracket 28 to the component body 140. Optionally, metallic parts can be attached to the bracket 28 by riveting, fastening, etc., or during injection molding to further increase load bearing capabilities.

The subject invention provides a CFRP bracket 28 overmolded into a main component body structure, such as a shock tower structure for example, which results in significant weight and cost reduction when compared to traditional steel and aluminum component structures. The subject invention provides an out-of-plane bracket that supports loading of an integrated component body where the overmolded interface of the bracket is sufficiently strong to provide an attachment interface to other load bearing components. In addition to being used in shock towers, the subject invention could be applied to other parts made by injection or compression molding and that require brackets out of the main plane of the part with load bearing capabilities and without draft angle.

Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.

Claims

What is claimed is:

1. A shock tower assembly comprising:

a shock tower body comprising a polymer composite material; and a wheel cover integrated into the shock tower body and/or at least one reinforcement member integrated into the shock tower body at a first overmold interface to form a single-piece component, wherein the at least one reinforcement member is comprised of at least one of a metal and a continuous fiber reinforced polymer composite material.

2. The shock tower assembly according to claim 1 wherein the at least one reinforcement member comprises at least one metal plate or bracket that is configured to mount the shock tower body to a fixed vehicle structure.

3. The shock tower assembly according to claim 1 wherein the at least one reinforcement member comprises at least one mount structure comprised of continuous fiber reinforced polymer composite material.

4. The shock tower assembly according to claim 3 wherein the at least one mount structure comprises a shock tower cap configured to receive a strut component, and/or wherein the at least one mount structure comprises a suspension control arm mount flange.

5. The shock tower assembly according to claim 1 wherein the at least one reinforcement member comprises at least one metal plate and at least one mount structure comprised of continuous fiber reinforced polymer composite material, and optionally, wherein the at least one metal plate is configured to mount the shock tower body to a fixed vehicle structure and the at least one mount structure comprises a suspension control arm mount flange and/or a shock tower cap configured to receive a strut component.

6. The shock tower assembly according to claim 5 wherein the first overmold interface is between the shock tower body and the at least one metal plate and including a second overmold interface between the at least one mount structure and the shock tower body.

7. The shock tower assembly according to claim 1 wherein the wheel cover is comprised of a polymer composite material and is integrated with the shock tower body to form the single-piece component.

8. The shock tower assembly according to claim 1 wherein the at least one reinforcement member comprises at least one plate comprised of the metal material integrated into the shock tower body at the first overmold interface and at least one mount structure comprised of the continuous fiber reinforced polymer composite material integrated into the shock tower body at a second overmold interface, and optionally, including a third overmold interface that integrates at least one of a nut, fastener, and sleeve into the shock tower body.

9. The shock tower assembly according to claim 1 wherein the at least one reinforcement member comprises at least one bracket composed of the continuous fiber reinforced polymer composite material, the bracket having a load bearing portion extending outwardly from the shock tower body and an overmolded portion that is attached to the shock tower body at the first overmold interface, and including at least one attachment feature formed in the load bearing portion of the bracket, wherein the attachment feature is configured to be attached to load bearing component, and optionally, wherein the at least one attachment feature comprises at least one of a hole and flange, and optionally, wherein the load bearing portion is free from polymer composite material.

10. A method of forming a shock tower assembly comprising:

(a) forming at least one reinforcement member from continuous fiber reinforced thermoplastic;

(b) surrounding a first portion of the reinforcement member with a polymer composite material to form a shock tower body; and (c) integrally molding the reinforcement member with the shock tower body to form a single-piece component, wherein the single-piece component comprises the shock tower body with an overmolded portion at the first portion of the reinforcement member and including a second portion of the reinforcement member extending outwardly from the shock tower body.

11. The method according to claim 10 wherein step (a) includes thermoforming the reinforcement member from a continuous fiber reinforced thermoplastic sheet to a predetermined shape.

12. The method according to claim 10 including forming at least one attachment feature at the overmolded portion of the reinforcement member.

13. The method according to claim 12 wherein the reinforcement member comprises a bracket, cap, flange, or plate, and wherein the at least one attachment feature comprises at least one hole, spacer, and/or fastener.

14. The method according to claim 10 including forming at least one attachment feature at the second portion of the reinforcement member, wherein the at least one attachment feature is configured to attach the shock tower assembly to a vehicle structure.

15. The method according to claim 10 including integrally molding a wheel cover comprised of the polymer composite material with the shock tower body to form the single-piece component.

16. The method according to claim 10 wherein step (a) further includes forming the at least one reinforcement member as a bracket that has a load bearing portion and an overmolded portion, and wherein step (b) further includes placing the bracket in an injection tool and injecting a polymer composite material into the injection tool to surround the overmolded portion of the bracket; and wherein step (c) further includes removing a finished component from the injection tool, wherein the finished component comprises the load bearing portion of the bracket extending outwardly from the finished component and the overmolded portion of the bracket that is surrounded by the polymer composite material.

17. The method according to claim 16 including trimming the bracket and forming at least one attachment feature at the overmolded portion of the bracket prior to step (b), and/or including trimming the bracket and forming at least one attachment feature at the load bearing portion of the bracket prior to step (b).

18. The method according to claim 17 wherein the at least one attachment feature is formed at the overmolded portion of the bracket, and wherein the attachment feature comprises at least one hole to facilitate mechanical bonding with the polymer composite material during injection molding, and/or wherein the attachment feature comprises at least one flange to facilitate mechanical bonding with the polymer composite material during injection molding.

19. The method according to claim 17 wherein the at least one attachment feature is formed at the load bearing portion of the bracket, and including providing at least one location feature in the injection tool for the bracket and further including, during step (b), inserting the load bearing portion of the bracket into the location feature such that the attachment feature is protected from the polymer composite material during injection molding, and applying pressure to opposing sides of the bracket to hold the bracket in place.

20. The method according to claim 19 wherein the location feature comprises a groove and wherein the attachment feature comprises at least one hole, and including inserting the load bearing portion of the bracket into the groove to position the bracket in the injection tool.

21. The method according to claim 19 including using at least a first slide to

5 apply pressure against a first side of the bracket and a second slide to apply pressure against a second side of the bracket opposite the first side such that the bracket is securely clamped between the first and second slides during injection of the polymer composite material to prevent the bracket from moving and to isolate the bracket from polymer composite material.