VEHICLE HOOD ARRANGEMENT WITH FOLDABLE PEDESTRIAN PROTECTION

Abstract

A hood assembly for a vehicle comprises an inner hood, an outer hood, and several deployable devices. The outer hood is fixed relative to the inner hood. The multiple deployable devices are spaced apart from each other between the inner and outer hoods. Each deployable device defines an inflation chamber and is made of thermoplastic elastomer. Upon detection of a collision between the vehicle and a pedestrian, the deployable devices unfold to separate the outer and inner hoods. This allows the outer hood to deform during the pedestrian's impact and / or keeps the pedestrian separated from relatively hard components beneath the hood assembly.

Description

[0001] The invention relates to a vehicle hood arrangement and a vehicle. BACKGROUND

[0002] A hood assembly according to an internal prior art of a vehicle may be designed to have a low profile, e.g., a relatively low hood height, which may permit a desired aerodynamic profile. However, such a design may bring hood assembly panels closer to relatively hard points beneath the hood assembly, e.g., a power unit. This reduces the crumple zone between the hood and the underlying hard points. A desire for a low-profile hood assembly design may conflict with design considerations that favor an increased crumple zone to reduce the likelihood of head impact injuries to pedestrians involved in pedestrian-vehicle collisions.Specifically, the increased "crumple zone" keeps the pedestrian away from the relatively hard points under the hood assembly, and / or it allows for greater deformation of the hood, which absorbs energy from the pedestrian and reduces their impact speed.

[0003] Therefore, one possibility remains to design an improved construction to allow a hood arrangement to have a flat profile and at the same time to implement design factors to reduce the likelihood of pedestrian injury in pedestrian-vehicle collisions.

[0004] DE 20 2013 009 616 U1 discloses a hood-integrated protective device with an airbag system arranged between the hood and the vehicle structure for increasing pedestrian protection in a collision. JP 2008-273308 A discloses a vehicle hood with a bubble-shaped structure that opens upon impact to improve impact protection by creating a gap to the underlying structure. WO 2007 / 085920 A1 discloses a system with an inflatable bumper that unfolds between two body structures to increase the deformation path in a collision. DE 100 63 586 A1 discloses an energy-absorbing vehicle hood with pre-deformed chambers and expandable struts that are activated by airbags or expansion foam. DE 100 57 941 A1 discloses a front hood with transverse airbag hoses that are filled segment by segment by gas generators to lift the outer hood and reduce the risk of injury.

[0005] The object of the invention is to provide a vehicle hood arrangement which, in the event of an impact, in particular with a pedestrian, enables a reliable and structured deployment of a protective device arranged between the inner and outer hood, wherein the protective device should be integrable in a space-saving manner, be functionally reliable and be stably connected to the hood components.

[0006] The problem is solved according to the invention by a vehicle hood arrangement with the features of claim 1. Furthermore, the problem is solved according to the invention by a vehicle with the features of claim 10.

[0007] The features of an inner hood and an outer hood, which are attached to one another, as well as an expandable device with a gas generator, are known from DE 20 2013 009 616 U1. However, it is not shown that several expandable devices, spaced apart from each other between the inner hood and the outer hood, wherein the expandable devices each define an inflation chamber and are made of thermoplastic elastomer; several gas generators, wherein each of the gas generators is arranged within one of the expandable devices; wherein each of the expandable devices has a clamp securing the respective gas generator, each clamp being designed as a single continuous unit with the respective expandable device. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view of a vehicle that includes a hood assembly. Fig. Figure 2 is a perspective view of the vehicle with several deployable hood assembly devices in deployed positions. Fig. Figure 3 is a partially separated view of the hood arrangement, with an upper hood pulled away from an inner hood to show the multiple deployable devices in between, the deployable devices being in un-deployed positions. Fig. Figure 4 is a partially separated view of the hood arrangement of Fig. 3, wherein one of the several deployable devices is in the deployed position. Fig. Figure 5 is a cross-sectional view of the hood arrangement, with one of the several deployable devices in the unfurled position. Fig. Figure 6 is a cross-sectional view of the hood arrangement, with one of the several deployable devices in the deployed position. Fig. Figure 7 is a schematic representation of a tax system. DETAILED DESCRIPTION

[0008] Referring to the figures, in which identical reference numerals denote identical parts across different views, a hood assembly 40 for a vehicle 30 comprises an inner hood 42, an outer hood 44, and several deployable devices 70. The outer hood 44 is attached to the inner hood 42. The several deployable devices 70 are spaced apart from each other between the inner hood 42 and the outer hood 44. Each deployable device 70 defines an inflation chamber 78 and is made of thermoplastic elastomer.

[0009] The multiple deployable devices 70 can be operated from a non-deployed position, as in the Fig. 1, Fig. 3 and Fig. 5 shown, in an unfolded position, as in the Fig. 2, Fig. 4 and Fig. As shown in Figure 6, the inner hood 42 and the outer hood 44 can be unfolded to move them relative to each other, e.g., to deform them. As shown in the Fig. 2 and Fig. As shown in Figure 6, during a collision between the vehicle 30 and the pedestrian, the multiple deployable devices 70, in their deployed position, selectively increase the space between the outer hood 44 and the relatively rigid components beneath the hood assembly, such as a power unit (not shown). This increased space can reduce the likelihood of pedestrian injury, such as head injuries. Simultaneously, the vehicle hood assembly 40 can have a low-profile design because the multiple deployable devices 70 are positioned between the inner hood 42 and the outer hood 44.

[0010] With regard to the Fig. 1 and Fig. 2 The vehicle 30 can include a front bumper 32 and the vehicle hood assembly 40. The hood assembly 40 is positioned in front of a windshield 34 and covers the engine. The front bumper 32 can be located below the front of the hood assembly 40 and can absorb energy in the event of a frontal collision of the vehicle 30. The front bumper 32 can carry an impact sensor 92, as described below.

[0011] With regard to the Fig. Figures 3-6 show the outer cover 44 positioned above the inner cover 42. As shown in the figures, the outer cover 44 is exposed when the cover assembly 40 is in a closed position. The outer cover 44 can have a Class A surface finish, such as a refined surface that is visible to a customer and free from unsightly blemishes and defects. The inner cover 42 and the outer cover 44 can be made of the same type of material. For example, the inner cover 42 and / or the outer cover 44 can be made of plastic, such as sheet molding composite (SMC), carbon fiber reinforced plastic (CFRP), fiberglass, and / or another fiber-reinforced plastic. Alternatively, the inner cover 42 and the outer cover 44 can be made of metal, such as aluminum, steel, etc.

[0012] The outer cover 44 is attached to the inner cover 42, that is, the outer cover 44 is attached directly or indirectly to the inner cover 42. Specifically, the inner cover 42 and the outer cover 44 can each include a mounting surface 86. The mounting surfaces 86 can be formed into a folded flange 54 that connects the inner cover 42 and the outer cover 44. Alternatively, the mounting surfaces 86 can be bonded together, e.g., by the application of adhesive, plastic welding, metal welding, etc. The mounting surfaces 86 can extend along an elongated path, generally along a periphery 88 of the inner cover 42 and / or the outer cover 44.

[0013] The periphery 88 of the hood assembly 40 can generally be rectangular. Specifically, the hood assembly 40 can comprise a left edge 56, a right edge 58 spaced from the left edge 56 in a transverse direction of the vehicle, a rear edge 55 extending from the left edge 56 to the right edge 58, and a front edge (unnumbered) spaced from the rear edge 55 and extending from the left edge 56 to the right edge 58. Specifically, the inner hood 42 (as shown in the figures), the outer hood 44, or both can comprise the left edge 56, the right edge 58, the rear edge 55, and the front edge. The left edge 56 and the right edge 58 can generally extend in a longitudinal direction of the vehicle, in other words, along a direction of travel of the vehicle. The rear edge 55 and the front edge can generally extend in a transverse direction of the vehicle.The rear edge 55 can extend along the windshield 34 from the left edge 56 to the right edge 58. Specifically, when the hood assembly 40 is closed, the rear edge 55 can extend along the windshield 34 adjacent to it, for example, without anything between the windshield 34 and the rear edge 55. The inner hood 42 can include a longitudinal center line 57 extending in the longitudinal direction of the vehicle between the left edge 56 and the right edge 58. The inner hood 42 can be symmetrical about the longitudinal center line 57.

[0014] The hood assembly 40 can be attached to the frame (unnumbered) of the vehicle 30 by a hinge (not shown). The hinge can be attached to the inner hood 42 and / or the outer hood 44. The inner hood 42, the outer hood 44, and the deployable device 70 move together as a unit around the hinge, for example, to provide access to the engine of the vehicle 30. A locking mechanism 60 can selectively secure the hood assembly 40 in a closed position relative to the body of the vehicle 30.

[0015] The locking mechanism 60 can be attached to the underside of the outer hood 44 to fasten to a fastening mechanism 62 above the front bumper 32. If, for example, someone wants to check the power unit 36, the locking mechanism 60 releases from the fastening mechanism 62, and the vehicle hood assembly 40 flips upwards as a unit at the hinge.

[0016] With regard to the Fig. 3 and Fig. 4. The multiple deployable devices 70 can be arranged at different locations within the periphery 88 between the inner cover 42 and the outer cover 44 and spaced apart from one another. The deployable devices 70 can be arranged at the periphery 88 or can be spaced inwards from the periphery 88. For example, at least one of the multiple deployable devices 70 can be arranged adjacent to the locking mechanism 60, e.g., above the locking mechanism 60. For example, one of the deployable devices 70 can be located adjacent to a portion of the locking mechanism 60 that projects vertically onto the inner cover 42. As a further example, at least one of the multiple deployable devices 70 can be adjacent to the right edge 58, and at least one of the multiple deployable devices 70 can be adjacent to the left edge 56.As a further example, at least one of the several deployable devices 70 can be adjacent to the rear edge 55. Specifically, at least one of the several deployable devices 70 can be arranged adjacent to the rear edge 55 on the longitudinal center line 57.

[0017] As explained below, the deployable devices 70 can be inflated to separate the outer hood 44 from the inner hood 42. Specifically, the deployable devices 70 can separate the outer hood 44 from the inner hood 42 along the periphery 88, for example, along the left edge 56, the right edge 58, the rear edge 55, and / or the front edge. The deployable devices 70 can separate the outer hood 44 from the inner hood 42 at discrete locations or can interact with each other to move the entire outer hood 44 away from the inner hood 42 as a single unit.

[0018] With regard to the Fig. 5 and Fig. 6. Each deployable device 70 may comprise a top plate 72, a bottom plate 74, and sides 76 connecting the top plate 72 and the bottom plate 74. The deployable devices 70 each define an inflation chamber 78; specifically, the sides 76 define the inflation chamber 78 between them. The inflation chamber 78 is enclosed by the top plate 72, the bottom plate 74, and the sides 76. The deployable device 70 may have vent openings (not shown) extending from the inflation chamber 78 through the top plate 72, the bottom plate 74, and / or the sides 76 to allow the deployable device 70 to deflate, for example, to allow the deployable device 70 to collapse and become soft upon a collision between the hood assembly 40 and a pedestrian.

[0019] The top plate 72, the bottom plate 74, and the sides 76 can be compression molded. In other words, the top plate 72, the bottom plate 74, and the sides 76 can be formed using a molding process in which a liquid or malleable material is formed under pressure in a mold, e.g., injection molding, blow molding, extrusion, etc.

[0020] The top plate 72 and the bottom plate 74 are each 1 to 3 millimeters thick. The top plate 72 and the bottom plate 74 can be the same thickness or they can be different thicknesses. The top plate 72 and / or the bottom plate 74 can be thicker than the sides 76.

[0021] The sides 76 can define folds 80 between the upper plate 72 and the base plate 74. The folds 80 are folded together when the unfoldable device 70 is in the unfolded position, and the folds 80 are unfolded when the unfoldable device 70 is in an unfolded position. The folds 80 can be arranged accordion-style or can be folded together in any other suitable manner.

[0022] Each deployable device 70 is made of thermoplastic elastomer (TPE). A thermoplastic elastomer exhibits both thermoplastic and elastomeric properties. A thermoplastic material becomes pliable above a certain temperature and solidifies upon cooling, while an elastomer generally has a low modulus of elasticity and high elongation at break. Types of TPEs include styrene block copolymers, thermoplastic olefins, elastomer alloys, thermoplastic polyurethanes, thermoplastic copolyesters, and thermoplastic polyamides. The material forming the deployable device 70 is a solid material, not woven like a fabric.

[0023] The unfoldable device 70 can be attached to the inner hood 42 (as shown in the Fig. 5 and Fig. 6) and / or be attached to the outer hood 44, e.g., adhesively connected to it. For example, the deployable device 70 can be attached to the inner hood 42 with adhesive 84, as shown in the Fig. 5 and Fig. 6 shown. Alternatively or additionally, the deployable device 70 can be attached to the inner hood 42 and / or the outer hood 44 by welding, such as ultrasonic welding, fasteners, etc.

[0024] The hood arrangement can comprise several gas generators 82, each connected to the inflation chamber 78 of one of the several deployable devices 70. Alternatively, the hood arrangement 40 can comprise one or more gas generators 82 that are fluidically connected to more than one of the inflation chambers 78 of the several deployable devices 70, i.e., more than one of the deployable devices 70 can share one of the gas generators 82. The gas generators 82 inflate the deployable devices 70 with an inflation medium, such as a gas.

[0025] The gas generators 82 can be located inside or outside the deployable devices 70. The gas generator 82 can be attached to the deployable devices 70 or can be located remotely from the deployable devices 70 and, for example, connected to the inflation chambers 78 via a filling tube. As an example of how in the Fig. 5 and Fig. As shown in Figure 6, each deployable device 70 can define at least one clamp 98 in the inflation chamber 78, which attaches one of the several gas generators 82 to this deployable device 70. The clamp can have any suitable size and shape to attach each gas generator 82 to each deployable device 70. The clamp can, for example, be integrally formed with the upper plate 72, the base plate 74 (as shown in the Fig. 5 and Fig. (shown in Figure 6) and / or the sides 76, i.e., formed simultaneously with the plate 72, the base plate 74 and / or the sides 76 as a single continuous unit. Alternatively, the clamp can be formed separately from the upper plate 72, the base plate 74 and / or the sides 76 and subsequently connected to them.

[0026] The gas generators 82 can, for example, be pyrotechnic gas generators 82 that utilize a chemical reaction to force the inflation medium into the deployable devices 70. The gas generators 82 can be of any suitable type, for example, cold gas generators.

[0027] With reference to Fig. 7. The vehicle 30 may include a control system 90 comprising at least one impact sensor 92 for detecting an impact of the vehicle 30 and a control unit 94 connected to the sensor 92 and the gas generator 82 for activating the gas generator 82, for example by providing a pulse to a pyrotechnic charge of the gas generator 82 when the sensor 92 detects an impact of the vehicle 30. Alternatively or in addition to detecting an impact, the control system 90 may be designed to detect an impending impact before the actual impact, i.e., pre-crash detection.

[0028] The impact sensor 92 is designed to detect an impact on the front bumper 32. The impact sensor 92 can be of any suitable type, for example, using radar, LiDAR, or a vision system. The vision system can include one or more cameras, CCD image sensors, CMOS image sensors, etc. The sensor 92 can be contained within the front bumper 32 or can be located elsewhere in the vehicle 30.

[0029] The controller 94 can be a microprocessor-based controller. The controller 94 can include a processor, memory, etc. The memory of the controller 94 can store instructions executable by the processor. The impact sensor 92 is connected to the controller 94 to transmit data to the controller 94. The controller 94 is programmed to instruct the gas generator 82 to inflate the deployable device 70 in response to an impact of a pedestrian detected by the impact sensor 92.

[0030] The control system 94 can transmit signals via a communication network 96 (such as a Controller Area Network (CAN) bus), Ethernet, and / or any other wired or wireless communication network. The control system 94 can use information from the communication network 96 to control the activation of the gas generators 82. The gas generators 82 can be connected to the control system 94, as shown in Fig. 7 shown, or can be directly connected to the 96 communication network.

[0031] In the event that the impact sensor 92 detects a collision with a pedestrian, the impact sensor 92 controls the controller 94 via the communication network 96. The controller 94 instructs the multiple gas generators 82 via the communication network 96 to inflate the multiple deployable devices 70. Depending on the signals received from the impact sensor, the controller 94 may selectively control only some of the multiple gas generators 82. The gas generators 82 thus controlled inflate the deployable devices 70 from the unfurled position (as in Fig. 1) into the unfolded position (as in Fig.2) The deployable devices 70, once deployed, press against the outer hood 44. The outer hood 44 may deform upward, for example, by approximately 2-3 inches. When the pedestrian impacts the outer hood 44, the outer hood 44 and / or the deployable devices 70 deform to absorb energy from the impact and keep the pedestrian separated from components below the hood assembly 40, such as the power unit, the locking mechanism 60, the left edge 56, the right edge 58, the rear edge 55, and / or the front edge. The energy absorbed by the hood assembly 40 may decrease the likelihood of the pedestrian impacting a component below the hood assembly 40 and / or may decrease the speed at which the pedestrian impacts such a component.

[0032] The revelation has been described in an illustrative manner, and it is understood that the terminology used is intended to be descriptive rather than restrictive. Many modifications and variations of the present revelation are possible in light of the above teachings, and the revelation can be implemented differently than specifically described here.

Claims

[1] Vehicle hood arrangement (40) comprising the following: an inner hood (42); an outer hood (44) which is attached relative to the inner hood (42); several deployable devices (70) spaced apart from each other between the inner hood (42) and the outer hood (44), wherein the deployable devices (70) each define an inflation chamber (78) and are made of thermoplastic elastomer; and several gas generators (82), each of the gas generators (82) being arranged within one of the deployable devices (70); wherein each of the deployable devices (70) has a clamp (98) securing the respective gas generator (82), wherein each clamp (98) is formed as a single continuous unit with the respective deployable device (70). [2] Vehicle hood arrangement (40) according to claim 1, further comprising an adhesive (84) between each of the multiple deployable devices (70) and the inner hood (42) or the outer hood (44). [3] Vehicle hood arrangement (40) according to claim 1, wherein the multiple deployable devices (70) each comprise an upper plate (72), a base plate (74) and sides (76) connecting the upper plate (72) and the base plate (74), and which further comprises an adhesive (84) which joins each of the molded base plates (74) of the deployable devices (70) and the inner hood (42). [4] Vehicle hood arrangement (40) according to claim 1, wherein the multiple deployable devices (70) each comprise an upper plate (72), a base plate (74) and sides (76) connecting the upper plate (72) and the base plate (74), and define the folds (80) between the upper plate (72) and the base plate (74), wherein the folds (80) are folded together when the deployable device (70) is in a non-deployed position, and wherein the folds (80) are unfolded when the deployable device (70) is in a deployed position. [5] Vehicle hood arrangement (40) according to claim 3, wherein the upper plates (72) and the bottom plates (74) are each 1 to 3 millimeters thick. [6] Vehicle hood arrangement (40) according to claim 1, which further comprises a locking device (60) which is attached to the outer hood (44) and the inner hood (42), wherein at least one of the several deployable devices (70) is arranged above the locking device (60). [7] Vehicle hood arrangement (40) according to claim 1, wherein the inner hood (42) comprises a right edge (58) and a left edge (56) and wherein at least one of the several deployable devices (70) is adjacent to the right edge (58) and at least one of the several deployable devices (70) is adjacent to the left edge (56). [8] Vehicle hood arrangement (40) according to claim 1, wherein the inner hood (42) comprises a rear edge (55) and a longitudinal center line (57) and wherein at least one of the deployable devices (70) is adjacent to the rear edge (55) and is arranged on the longitudinal center line (57). [9] Vehicle hood arrangement (40) according to one or more of the preceding claims, wherein the deployable devices (70) are each made of thermoplastic elastomer, wherein the multiple deployable devices (70) each comprise a molded upper plate (72), a molded base plate (74) and sides (76) connecting the upper plate (72) and the base plate (74), which define an inflation chamber (78) between them. [10] Vehicle (30) comprising the following: a vehicle hood arrangement (40) according to one or more of the preceding claims; an impact sensor (92); and a control unit (94) programmed to instruct the gas generator (82) to inflate the deployable device (70) in response to an impact of a pedestrian detected by the impact sensor (92). [11] Vehicle (30) according to claim 10, further comprising a front bumper (32), wherein the sensor (92) is configured to detect an impact on the front bumper (32).

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