Bumper with non-linear spring

Abstract

A vehicle includes a vehicle frame with a frame member end. The frame member end has a frontal and a rearward surface. The vehicle includes a bumper located in front of the frame member end relative to the vehicle. A rod supports the bumper at the frame member end. The rod is fixed to the bumper and extends slidably through the frontal and rearward surfaces of the frame member end. A head is fixed to the rod and is held behind the rearward surface of the frame member end relative to the vehicle. A spring is located on the rod. The spring has a progressive nonlinear spring rate.

Description

AREA OF TECHNOLOGY

[0001] This revelation concerns a vehicle bumper. GENERAL STATE OF THE ART

[0002] The Global Technology Regulation (GTR) and the New Car Assessment Program (NCAP) establish criteria for protecting pedestrians from leg injuries. These regulations aim to reduce the impact force of a vehicle bumper on a pedestrian's legs during a vehicle-pedestrian collision. In addition, there are standardized tests, including those conducted by the U.S. National Highway Traffic Safety Administration (NHTSA), for a frontal impact.

[0003] Some vehicles, such as light commercial vehicles and SUVs, may have bumper heights that could result in uneven impact of the vehicle bumper on the pedestrian's femur and / or tibia during a vehicle-pedestrian collision. For example, light commercial vehicles may have bumper heights to provide ground clearance for driving over speed bumps, curbs, parking blocks, ramps, hills, rough roads, and so on. Some vehicles with such bumper heights also have off-road capabilities, which precludes the presence of components below the bumper. Therefore, there is an opportunity to design a vehicle's front end to manage the energy of an impact on a pedestrian's leg while simultaneously meeting ground clearance requirements. SUMMARY

[0004] According to the present invention, a vehicle is provided comprising: a vehicle frame having a frame member end, wherein the frame member end has a vehicle-forward surface and a vehicle-rear surface; a bumper located in front of the frame member end with respect to the vehicle; a rod supporting the bumper on the frame member end, wherein the rod is fixed to the bumper and extends slidably through the vehicle-forward surface and the vehicle-rear surface of the frame member end; a head fixed to the rod and held behind the vehicle-rear surface by the frame member end with respect to the vehicle; and a spring on the rod, wherein the spring has a progressive non-linear spring rate.

[0005] According to one embodiment, the bumper is movable rearward from an extended position towards the end of the frame support relative to the vehicle, with the spring being loaded in the extended position between the vehicle frame and the bumper.

[0006] According to one embodiment, the spring is elastically compressible between the frame support end and the bumper.

[0007] According to one embodiment, the spring includes a front collar that engages with the rod adjacent to the bumper, a rear collar that is spaced apart from the rear collar along an axis of the rod and engages with the rod adjacent to the frame support end, and a plurality of arcs extending from the front collar to the rear collar and fixed to the front collar and the rear collar.

[0008] According to one embodiment, the arcs are elongated along the axis of the rod.

[0009] According to one embodiment, the front collar is in slidable engagement with the rod and the rear collar is in slidable engagement with the rod.

[0010] According to one embodiment, the front collar rests against the bumper and the rear collar rests against the end of the frame support.

[0011] According to one embodiment, the front collar is cylindrical and the rear collar is cylindrical, with the arcs positioned circumferentially around the front collar and the rear collar.

[0012] According to one embodiment, the arcs between the front collar and the rear collar bend outwards away from the rod.

[0013] According to one embodiment, the arches are designed to bend elastically during a pedestrian impact test, and the arches are designed to deform plastically during a frontal impact test.

[0014] According to one embodiment, the spring is a conical helical spring.

[0015] According to one embodiment, the conical helical spring is wound around the rod.

[0016] According to one embodiment, the conical coil spring rests against the bumper and the end of the frame support.

[0017] According to one embodiment, the invention is further characterized by a locking mechanism which detachably connects the rod to the frame support end.

[0018] According to one embodiment, the locking mechanism is rotatably connected to the vehicle-forward surface of the frame support end, with the locking mechanism being in releasable engagement with the rod behind the vehicle-rear surface.

[0019] According to one embodiment, the locking mechanism includes a front section rotatably connected to the vehicle's forward surface, a rear section located behind the vehicle's rear surface relative to the vehicle, an intermediate section extending from the front section to the rear section, and a weight that can be moved forward on the intermediate section relative to the vehicle.

[0020] According to one embodiment, the invention is further characterized by a plate which is fixed to the rod and is in releasable engagement with the locking mechanism.

[0021] According to one embodiment, the locking mechanism is driven by inertia from a locked position, in which the rod is connected to the frame support end, and an unlocked position, which is separated from the rod and / or the frame support end.

[0022] According to one embodiment, the frame support end includes a base that is elongated along a longitudinal axis of the vehicle, and a flange that extends radially from the base, and the flange includes the vehicle-forward surface and the vehicle-rear surface. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view of a section of a vehicle, including a bumper and vehicle frame, which are shown in dashed lines. Fig. Figure 2 is an exploded view of a section of the vehicle. Fig. Figure 3 is a perspective view of a vehicle rear side of a section of the bumper with an example of springs. Fig. Figure 4 is an exploded view of the bumper and one frame member end made of Fig. 3. Fig. 5A is a top view of the bumper in an extended position. Fig. 5B is a top view of the bumper in a compressed position. Fig. 5C is a top view of the bumper, which is further compressed by plastic deformation of springs. Fig. Figure 6 is a perspective view of a vehicle rear side of a section of the bumper with another example of springs. Fig. 7A is a top view of the bumper in an extended position. Fig. 7B is a top view of the bumper in a compressed position. Fig. Figure 8 is a perspective view of a vehicle rear side of a section of the bumper with a locking mechanism. Fig. 9A is a side view of the frame girder end with the locking mechanism in a locked position. Fig. 9B is a side view of the frame support end with the locking mechanism in an unlocked position. Fig. Figure 10 is an example force-displacement curve of a progressive nonlinear spring. DETAILED DESCRIPTION

[0023] Referring to the figures, in which the same reference numerals denote identical parts in the different views, a vehicle 10 comprises a vehicle frame 12 with a frame member end 14. The frame member end 14 has a vehicle-forward surface 16 and a vehicle-rearward surface 18. The vehicle 10 includes a bumper 20, which is located in front of the frame member end 14 relative to the vehicle. A rod 22 supports the bumper 20 against the frame member end 14. The rod 22 is fixed to the bumper 20 and extends slidably through the vehicle-forward surface 16 and the vehicle-rearward surface 18 of the frame member end 14. A head 24 is fixed to the rod 22 and is held behind the vehicle-rear surface 18 by the frame member end 14 relative to the vehicle. A spring 26, 126 is located on the rod 22. The spring 26, 126 has a progressive nonlinear spring rate.

[0024] The spring 26, 126 pushes the bumper 20 forward relative to the vehicle, with the head 24 holding the rod 22 at the frame member end 14. The spring 26, 126 absorbs energy during certain vehicle impacts, such as pedestrian impacts. For example, during a pedestrian impact, the bumper 20 moves against the preload of the spring 26, 126 toward the frame member end 14 to absorb energy from the impact and reduce energy transferred from the bumper 20 to the pedestrian. In particular, the bumper 20 moves from an extended position, as in the Fig. 5A and Fig. 7A shown, in a compressed position, as in the Fig. 5B and Fig. Figure 7B shows the impact when the bumper is struck by a force sufficient to compress the spring 26, 126. Since the spring 26, 126 has a progressive nonlinear spring rate, the force required to displace the bumper 20 rearward relative to the vehicle increases with the displacement. Accordingly, force absorption is smoother at lower speeds and increases with increasing force. In some examples, the bumper 20 is resettable after an impact. In such examples, the spring 26, 126 returns to its extended position after the force on the bumper 20 is removed.

[0025] The bumper 20 can, for example, impact the knee of a pedestrian impact test leg during a standardized test. The leg shape can be that of a Flexible Pedestrian Leg Impactor (Flex-PLI). Examples of regulations that may use this leg shape include the Global Technical Regulations (GTR), ECE R127, and the Korean Motor Vehicle Safety Standards (KMVSS). Examples of new car rating programs that may use this leg shape include Euro NCAP, CNCAP, and ANCAP. In a frontal impact test, the bumper 20 can impact a fixed barrier, such as a fixed barrier impact at 35 mph during an NHTSA test.

[0026] Vehicle 10 can be any suitable type of automobile, e.g., a passenger car or commercial vehicle, such as a sedan, a coupé, a truck, an SUV, a crossover vehicle, a van, a minivan, a taxi, a bus, etc. Vehicle 10 can, for example, have a relatively high ground clearance.

[0027] With reference to Fig. In section 1, vehicle 10 is defined by a longitudinal axis L extending between a front end (no reference numeral) and a rear end (no reference numeral) of vehicle 10. Vehicle 10 is defined by a transverse axis A extending across the vehicle from one side to the other. Vehicle 10 is defined by a vertical axis V. The longitudinal axis L, the transverse axis A, and the vertical axis V are perpendicular to each other.

[0028] The vehicle 10 comprises the vehicle frame 12 and a vehicle body. The vehicle body and the vehicle frame 12 can have a ladder frame construction (also referred to as a cab-on-frame construction), in which the vehicle body and the vehicle frame 12 are separate components, i.e., modular, and the vehicle body is supported on and fixed to the vehicle frame 12. In the example shown in the figures, the vehicle 10 has a ladder frame construction. As another example, the vehicle body and the vehicle frame 12 can have a unibody construction, in which the vehicle frame 12 is formed integrally with the vehicle body (including frame members 28, pillars, roof rails, etc.). Alternatively, the vehicle frame 12 and the vehicle body can have any suitable construction.The vehicle frame 12 and the vehicle body can be made of any suitable material, for example steel, aluminium and / or fiber reinforced plastic, etc.

[0029] The vehicle body comprises body panels. The body panels may include structural panels, such as sills, pillars, roof rails, etc. The body panels may include outer panels. The outer panels may represent a Class A surface, such as a finished surface visible to the customer and free from unsightly blemishes and defects. The body panels include, for example, roof panels, doors, fenders, hood, trunk lid, etc. The vehicle body may define a passenger compartment to accommodate any occupants of the vehicle.

[0030] The vehicle frame 12 includes frame members 28 and may include cross members. The frame members 28 extend along the longitudinal axis A of the vehicle. The frame members 28 are spaced apart from each other in the transverse direction of the vehicle. The cross members of the vehicle frame 12 extend from one frame member 28 to the other, transversely to the longitudinal axis A of the vehicle.

[0031] The vehicle frame 12 includes two frame members 28. The frame members 28 can define the transverse boundaries of the vehicle frame 12. The frame members 28 can extend along the longitudinal axis A of the vehicle from a rear end to a front end. For example, the frame members 28 can extend along substantially the entire length of the vehicle 10. In other examples, the frame members 28 can be segmented and extend under sections of the vehicle 10, e.g., extending at least from below a passenger compartment of the vehicle 10 to the front end of the vehicle 10. In some examples, each frame member 28 can be a single piece from the rear end to the front end of the vehicle 10. In other examples, the frame members 28 can include segments that are fixed to one another (e.g., by welding, threaded fasteners, etc.).) and extend in combination from a rear end of the vehicle 10 to the front end of the vehicle 10.

[0032] As described above, the vehicle frame 12 can have a ladder frame design, in which the vehicle body is supported on and attached to the vehicle frame 12. In such an example, the frame members 28 can include cab mounting brackets (not shown) on which the vehicle body is supported and to which it is attached. The cab mounting brackets are fixed to the frame members 28, for example, by welding them. The cab mounting brackets can extend outwards from the frame member 28. The cab mounting bracket can cantilever from the frame member 28. The cab mounting brackets are configured to support the vehicle body in a ladder frame configuration. For example, the cab mounting bracket can include a bar or hole that accommodates a hole or bar in the vehicle body to connect the vehicle body to the vehicle frame 12.In particular, the vehicle body can be fixed to the cabin mounting bracket. During the assembly of the vehicle 10, the vehicle body is placed onto the vehicle frame 12, with the fastening features of the vehicle body being aligned with the cabin mounting brackets to engage with the cabin mounting brackets.

[0033] The vehicle frame 12 may include suspension and steering mounting points (not shown) that support the suspension and steering components of the vehicle 10. For example, the suspension and steering mounting points may be suspension strut towers. The suspension and steering components of the vehicle 10 are connected to the vehicle frame 12, at least partially, via the suspension strut towers. The suspension and steering components include suspension dampers, shock absorbers, steering arms, steering knuckles, wheels of the vehicle 10, etc.

[0034] The vehicle frame 12 can have a powertrain compartment designed to support and accommodate a powertrain of the vehicle 10 between the frame members 28. For example, at least one of the cross members of the vehicle frame 12 can be a powertrain support, i.e., a cross member designed to support and be fixed to the powertrain of the vehicle 10. The powertrain support can define a boundary of the powertrain compartment, e.g., a lower boundary of the powertrain compartment. The powertrain of the vehicle 10 in the powertrain compartment can, for example, consist of an internal combustion engine and a transmission, in which case the powertrain support is an engine mount. In other examples, the vehicle frame 12, e.g., the frame members 28 and / or the cross members, is designed to support battery assemblies.The battery assembly can be any type suitable for vehicle electrification to supply power to the vehicle 10 drive system, for example lithium-ion batteries, nickel-metal hydride batteries, lead-acid batteries or ultracapacitors, such as those used in plug-in hybrid electric vehicles 10 (PHEVs), hybrid electric vehicles 10 (HEVs) or battery electric vehicles 10 (BEVs), etc.

[0035] The frame members 28 and cross members can be extruded, rolled, etc. The frame members 28 and cross members of the vehicle frame 12 can be made of any suitable material, e.g., suitable types of steel, aluminum, and / or fiber-reinforced plastic, etc. The frame members 28 and cross members can be hollow. The frame members 28 and cross members can have a rectangular cross-section (e.g., a hollow rectangular prism), a circular cross-section (e.g., a hollow cylinder), etc.

[0036] The vehicle frame 12 includes the frame member ends 14, each of which extends in front of the frame members 28 with respect to the vehicle. In other words, the vehicle frame 12 includes two frame member ends 14, one of which extends in front of one of the frame members 28 with respect to the vehicle, and the other of which extends in front of the frame member 28 with respect to the vehicle.

[0037] The frame member end 14 is fixed to the respective frame member 28. For example, the frame member end 14 can be fixed to the respective frame member 28 by welding, fastening, etc. In the example shown in the figures, the frame member end 14 is a component of the vehicle frame 12, which has a ladder frame architecture as described above. In other examples, the vehicle frame 12 may have a different architecture, e.g., a unibody architecture. In such examples, the frame member 28 is a component of the vehicle frame 12, which has a one-piece architecture, and the frame member end 14 is connected to such a frame member 28.

[0038] The frame member end 14 extends along the vehicle's longitudinal axis A. For example, the frame member end 14 can be coaxial with the frame member 28 at the junction of the frame member end 14 and the frame member 28. The frame member 28 has a vehicle-forward end, and the frame member end 14 extends forward from the vehicle-forward end of the frame member 28 with respect to the vehicle. In particular, the frame member end 14 has a vehicle-rear end at the frame member 28 and a vehicle-forward end at the springs 26, 126, as described in more detail below.

[0039] The frame member end 14 includes a base 30, which is elongated along a longitudinal axis A of the vehicle, and a flange 32, which extends radially from the base 30. The base 30 may be located at the rear end of the frame member end 14. The flange 32 may be located at a front end of the frame member end 14, as shown in the example illustrated in the figures.

[0040] The vehicle-forward surface 16 faces in the direction of vehicle travel. The vehicle-forward surface 16 can be flat, as shown in the example in the figures. As shown below, the spring 26, 126 rests against the vehicle-forward surface 16 of the frame member end 14 at the flange 32. In the example shown in the figures, the vehicle-forward surface 16 of the flange 32 is located at the vehicle-forward end of the frame member end 14.

[0041] The frame member end 14 includes a bore at its vehicle-forward end. The bore extends through the vehicle-forward end of the frame member end 14. In other words, the bore at the vehicle-forward end of the frame member 28 is open. The bore can extend through the frame member end 14, through both the vehicle-forward and vehicle-rearward ends of the frame member 28. The bore is elongated along the vehicle's longitudinal axis A. The frame member end 14 can be extruded, rolled, etc. The frame member end 14 can be made of any suitable material, e.g., suitable types of steel, aluminum, and / or fiber-reinforced plastic, etc. The frame member end 14 can be hollow, i.e., the bore makes the frame member end 14 hollow. The frame members 28 and cross members can have a rectangular cross-section (e.g.,a hollow rectangular cuboid), have a round cross-section, e.g. a hollow, round one, such as a hollow cylinder, etc.

[0042] The frame member ends 14 are designed to deform relative to the frame member 28 during a frontal vehicle impact. Specifically, the frame member ends 14 deform rearward relative to the vehicle to allow the bumper assembly 20 to move backward relative to the frame members 28, thereby absorbing energy during certain vehicle impacts. The frame member ends 14 may include features that direct deformation of the frame member end 14 toward the frame member 28 during a frontal impact of the bumper 20. These features may include wall geometry, wall thickness, recesses, cutouts, etc. The frame member ends 14 may be referred to in the industry as crumple zones.

[0043] With reference to the Fig. 1-3 The vehicle 10 has a front structure. The front structure includes a radiator grille and the bumper. The radiator grille is located above the bumper 20. The radiator grille can be a component of the vehicle body and can be supported by other components of the vehicle body.

[0044] The bumper 20 is connected to the vehicle frame 12. In particular, the bumper 20 is connected to the frame support ends 14 via the rods 22, as described in more detail below.

[0045] The bumper 20 extends transversely to the frame members 28, e.g. in a vehicle transverse direction C. With reference to the Fig. In Figures 1-3, the bumper 20 is elongated along the transverse direction C of the vehicle. The bumper 20 is supported by the vehicle frame 12, i.e., the weight of the bumper 20 is borne by the vehicle frame 12. The bumper 20 can be a front bumper, as shown in the figures.

[0046] In other words, the bumper assembly 20 can be located at the front of the vehicle 10, and in such examples, the bumper 20 is suitable for frontal collisions of the vehicle 10.

[0047] The bumper 20 has a vehicle-front surface 34. The vehicle-front surface 34 can be a Class A surface, i.e., a surface specifically manufactured to have a high-quality, finished, aesthetic appearance free from blemishes. In some examples, the Class A surface of the vehicle-front surface 34 of the bumper 20 can be chrome-plated. The bumper 20 can be made of any suitable material, such as metal (steel, aluminum, etc.), fiber-reinforced plastic, etc.

[0048] The bumper 20 includes at least one rod 22 and a corresponding spring 26, 126. In the example shown in the figures, the bumper 20 includes four rods 22 and springs 26, 126 at each frame member end 14. The energy-absorbing assemblies support the bumper 20 at the vehicle-forward end of the frame member end 14.

[0049] The rod 22 is movable with the bumper 20 relative to the frame member end 14 between the extended position and the compressed position. In particular, as described below, the bumper 20 and the rod 22 move as a unit relative to the frame member end 14 between the extended position and the compressed position. The rods 22 support the bumper 20 at the frame member end 14; that is, the weight of the bumper 20 is borne by the frame member end 14 via the rods 22.

[0050] The rods 22 extend along the vehicle's longitudinal axis A from the bumper 20 to the flange 32. The rods 22 pass through the flange 32, as described in more detail below. The rods 22 are fixed to the bumper 20. In particular, one end of the rod 22 can be fixed to the bumper 20, for example, by welding or thread engagement (e.g., thread engagement with a weld nut fixed to the bumper 20). The bumper 20 can have a bracket on its rearward side, as shown in the example in the figures, and the rods 22 can be fixed to the bracket. In such examples, the bracket can be fixed relative to the frontal Class A surface 34 of the bumper 20. The rods 22 can, for example, be made of metal.The rods 22 are rigid, so that the rods 22 with the bumper 20 move in relation to the flange 32 when the springs 26, 126 are compressed, as described in more detail below.

[0051] The rods 22 extend slidably through the flange 32, while the rod 22 moves back and forth between the extended position and the compressed position. The rod 22 extends through the vehicle-forward surface 16 and the vehicle-rear surface 18 of the frame member end 14. The flange 32 includes a rod hole 36, and the rods 22 extend through the rod hole 36, through a vehicle-forward surface 16 and a vehicle-rear surface 18 of the flange 32. A head 24 on the rod 22 holds the rod 22 in the rod hole 36. In particular, the head 24 rests against the vehicle-rear surface 18 of the flange 32, and the rod 22 extends from the head 24 forward, relative to the vehicle, through the flange 32. The head 24 and the rod 22 cannot be formed in one piece, i.e., they cannot be formed separately and then assembled, e.g.,A nut that engages by thread engagement (such as a lock nut, a pinned nut, etc.). As another example, the head 24 can be formed integrally with the rod 22. In other words, the head 24 and the rod 22 can be a single, unified piece of material not held together by seams, connecting elements, fasteners, or adhesives; that is, they can be formed simultaneously as a single, continuous unit, e.g., by machining from a single blank, forming, forging, casting, etc.

[0052] The head 24 is held behind the rear surface 18 of the vehicle by the frame member end 14. In the example shown in the figures, the outer diameter of the head 24 is larger than the diameter of the rod hole 36, so that the head 24 is held behind the rear surface 18 of the flange 32 relative to the vehicle. The head 24 can bear against the rear surface 18 of the flange 32 against the preload of the spring 26, 126 when the bumper 20 is in the extended position. If the bumper 20 is struck with sufficient force to compress the spring 26, 126, the rod 22 and the head 24 move rearward relative to the vehicle while the spring 26, 126 is compressed.In particular, as the head 24 moves rearward relative to the vehicle, the head 24 also moves rearward relative to the rearward surface 18 of the flange 32. When force is released from the bumper 20, the springs 26, 126 extend to move the head 24 toward the rearward surface 18 of the flange 32 until the bumper 20 reaches the extended position, e.g., when the head 24 rests against the rearward surface 18 of the flange 32 in the extended position.

[0053] The spring 26, 126 is located between the flange 32 and the bumper 20. Specifically, the spring 26, 126 can bear against the flange 32 and the bumper 20, e.g., the bumper 20's mounting bracket, in both the extended and compressed positions of the resettable energy absorber. The spring 26, 126 pre-tensions the bumper 20 forward relative to the flange 32 with respect to the vehicle. In particular, the spring 26, 126 uses the flange 32 as a reaction surface to pre-tension the bumper 20 forward with respect to the vehicle. The head 24 on the rod 22 holds the resettable energy absorber and the bumper 20 in the extended position when no force is applied to the bumper 20 sufficient to compress the spring 26, 126. The spring 26, 126 is elastically compressible between the flange 32 and the bumper 20.In other words, the spring 26, 126 is compressed when forces on the bumper 20 exceed a force sufficient to compress the spring 26, 126, and when the force is removed from the bumper 20, the spring 26, 126 returns to its pre-compression state. Specifically, in the extended position, the spring 26, 126 pulls the bumper 20 forward relative to the vehicle, so that the head 24 rests against the rearward surface 18 of the flange 32. When the force on the bumper 20 exceeds a threshold sufficient to compress the spring 26, 126, the spring 26, 126 is compressed, allowing the bumper 20 to move rearward relative to the flange 32 and the head 24 to move rearward relative to the flange 32. When the force is removed from the bumper 20, the spring 26, 126 in some examples (e.g.In the event of a pedestrian collision, the spring 26, 126 moves the bumper 20 forward relative to the vehicle and returns the head 24 so that it rests against the rear surface 18 of the vehicle. In other words, in some examples (e.g., in a pedestrian collision), the spring 26, 126 is elastically compressible between the frame member end 14 and the bumper 20.

[0054] An example of spring 26 is in the Fig. 1-5B is shown and another example of spring 126 is in the Fig. Figures 6-7B illustrate this. In both examples, the spring 26, 126 can be located on the rod 22 between the bumper 20 and the flange 32, as shown in the figures. In other words, the rod 22 extends through the spring 26, 126 between the bumper 20 and the flange 32.

[0055] In the Fig. In the examples shown in Figures 1-7B, the spring 26, 126 is loaded in the extended position between the vehicle frame 12 and the bumper 20. In other words, the spring 26, 126 is partially compressed in the extended position, so that the spring 26, 126 preloads the bumper 20 in the extended position, with, for example, the head 24 bearing against the vehicle-rear surface 18 of the flange 32 in the examples shown in the figures. Since the spring 26, 126 is loaded in the extended position, it resists axial movement of the rod 22 relative to the flange 32 during operation of the vehicle 10 in the absence of forces on the bumper 20 on a magnitude comparable to that of a vehicle impact, such as a pedestrian collision, a frontal collision, etc.

[0056] In the Fig. In the examples shown in Figures 1-7B, spring 26, 126 exhibits a progressive nonlinear spring rate. The spring rate is the ratio between the force on spring 26, 126 and the displacement of spring 26, 126, which can be represented by a force-displacement curve. The force-displacement curve is nonlinear. Since the spring rate is progressive, the slope of the force-displacement curve, in particular, increases. An example of the force-displacement curve for a progressive nonlinear spring rate is shown in Figure 1-7B. Fig. 10 shown and the spring 26 and / or the spring 126 can form the force-displacement curve or a similar curve to the one in Fig. 10 shown during the movement of the bumper from the extended position to the compressed position.

[0057] In the Fig. In the example shown in Figure 1-5B, the spring 26 comprises a front collar 38 that engages the rod 22 adjacent to the bumper 20, a rear collar 40 that is spaced from the rear collar 40 along an axis of the rod 22 and engages the rod 22 adjacent to the frame member end 14, and a plurality of arcs 42 extending from the front collar 38 to the rear collar 40 and fixed to the front collar 38 and the rear collar 40. In the extended position, the arcs 42 between the front collar 38 and the rear collar 40 are subjected to compression to hold the bumper 20 in the extended position in the absence of a force on the bumper 20. When a force is applied to the bumper 20 that overcomes the force of the spring 26, e.g.,Under the force of a pedestrian impact or a frontal vehicle impact, the arcs 42 bend outwards, while the rod 22 moves backwards through the rod hole 36 relative to the flange 32. In both examples shown in the figures, the spring 26 can be made of metal or any other suitable material.

[0058] The arches 42 can be designed to bend elastically. For example, the arches 42 can bend elastically when compressed under certain forces, such as forces associated with a pedestrian impact. In some examples, including the one in the Fig. In the example shown in 5A-5C, the arches 42 are designed (e.g., dimensioned, shaped, positioned, material selection) to withstand a pedestrian impact test (as in Fig. 5B) to bend elastically, and are designed to deform plastically during a full-coverage frontal impact test (as shown in Fig. (5C shown). In particular, the arches 42 are designed to bend elastically when subjected to forces on the order of magnitude of pedestrian impact tests and to deform plastically when subjected to forces on the order of magnitude of full-overlap frontal impact tests. When elastically deformed, the arches 42 deform from an initial position under the application of force and return to the initial position when the force is removed. When plastically deformed, the arches 42 deform permanently. Examples include a pedestrian impact test of the type described above and a full-overlap frontal impact test of the type described above.

[0059] The rod 22 extends through the spring 26. In particular, in the example shown in the figures, the front collar 38 and the rear collar 40 are continuous around the rod 22, and the arcs 42 are positioned circumferentially around the rod 22. The arcs 42 are elongated along the axis L of the rod 22. In other words, the longest dimension of the arc 42 lies along the axis L. The arcs 42 bend outwards away from the rod 22 between the front collar 38 and the rear collar 40. When force is applied to the front bumper 20 that overcomes the preload of the arcs 42, the arcs 42 bend further outwards away from the rod 22.

[0060] The arcs 42 are positioned circumferentially around the front collar 38 and the rear collar 40. The arcs 42 are fixed to the front collar 38 and the rear collar 40. The ends of the arcs 42 at the front collar 38 do not move relative to the front collar 38, and the ends of the arcs 42 at the rear collar 40 do not move relative to the rear collar 40. In some examples, the arcs 42 may be connected to the front collar 38 and / or the rear collar 40 by one-piece formation (i.e., formation as a single unit by forming, machining from a blank, etc.), welding, gluing, mechanical fasteners, etc. In such examples, a mechanical connection between the arcs 42 and the collars holds the arcs 42 to the collars, including before the spring 26 is mounted on the rod 22.In other examples, the front collar 38 and the rear collar 40 can clamp the ends of the arcs 42 between the collar and the rod 22. In such examples, the tension of the arcs 42 against the collars 38, 40 due to the preload of the spring 26 can hold the arcs 42 in the collars 38, 40 without a connection between the arcs 42 and the collars 38, 40.

[0061] In some examples, the front collar 38 is in slidable engagement with the rod 22, and the rear collar 40 is also in slidable engagement with the rod 22. In such examples, the arcs 42 push the front collar 38 towards the bumper 20 and push the rear collar 40 towards the flange 32. In some examples, the front collar 38 rests against the bumper 20 and / or the rear collar 40 rests against the frame member end 14; that is, the front collar 38 is in direct contact with the bumper 20 and / or the rear collar 40 is in direct contact with the frame member end 14. For example, in the example shown in the figures, the front collar 38 rests against the bumper 20 and the rear collar 40 rests against the flange 32 of the frame member end 14.For example, in the example shown in the figures, the front collar 38 is cylindrical, the rear collar 40 is cylindrical, and the rod 22 is cylindrical. The front collar 38 and the rear collar 40 are dimensioned such that they slide on the rod 22.

[0062] In the Fig. In the example shown in Figure 6-7B, the spring 126 is a conical helical spring. The outer diameter of the conical helical spring 126 decreases progressively from one end of the spring 126 to the other end. In other words, the conical spring 126 tapers from one end to the other. In such an example, the tapered end of the conical spring 126 deforms more easily than the wider end, resulting in the progressive nonlinear spring rate of the conical helical spring 126. In some examples, the thickness of the wire of the spring 126 can increase from one end to the other, e.g., from the tapered end to the wide end, to vary the progressive nonlinear spring rate.In some examples, the coils of the conical helical spring 126 can have outer diameters dimensioned such that the coils bend into each other when the conical helical spring 126 is fully compressed.

[0063] The conical coil spring 126 can be wound around the rod 22, as shown in the example in the figures. One end of the conical coil spring 126 can rest against the bumper 20 and the other end of the conical coil spring 126 can rest against the flange 32 of the frame support end 14.

[0064] In the Fig. In the example shown in Figures 8-9B, a locking mechanism 44 can detachably connect the rod 22 to the frame girder end 14. When the locking mechanism 44 connects the rod 22 and the frame girder end 14, as shown in Fig. As shown in Figure 9A, the locking mechanism 44 prevents relative movement of the bumper 20 with respect to the frame member end 14 by preventing movement of the rod 22 with respect to the frame member end 14. In the event of a vehicle impact, as shown in Figure 9A, the locking mechanism 44 prevents movement of the bumper 20 relative to the frame member end 14 by preventing movement of the rod 22 relative to the frame member end 14. Fig. As shown in Figure 9B, the locking mechanism 44 releases the rod 22 from the frame carrier end 14 and allows the rods 22 to move back and forth in the rod hole 36, so that the bumper 20 can move rearward relative to the frame carrier end 14. This is shown in the Fig. The example shown in Figures 8-9B represents the conical coil spring 126, and in other examples the locking mechanism 44 can be combined with the one shown in the Fig. Spring 26 shown in 1-5B is used.

[0065] The locking mechanism 44 is rotatably connected to the vehicle-forward surface 16 of the frame member end 14. For example, the locking mechanism 44 can include a hinge 46 connected to the vehicle-forward surface 16. The hinge 46 can be any suitable type of hinge, including, for example, the one described in the Fig. 8-9B depicted pin hinge.

[0066] The locking mechanism 44 extends rearward relative to the vehicle to engage the rod 22 behind the rear surface 18 of the vehicle. Specifically, the locking mechanism 44 includes a front section 48 rotatably connected to the front surface 16 of the vehicle, a rear section 50 located behind the rear surface 18 of the vehicle, and an intermediate section 52 extending from the front section 48 to the rear section 50. In the case of the Fig. In the example shown in Figures 8-9B, the locking mechanism 44 is generally U-shaped. The rear section 50 may extend rearward from the intermediate section 52 at a non-right angle to the vehicle to allow the locking mechanism 44 to release the flange 32 when the locking mechanism 44 moves from a locked position, as shown in Figure 8-9B. Fig. 9A shown, rotates into an unlocked position, as shown in Fig. 9B is shown.

[0067] The locking mechanism 44 engages the rod 22 behind the vehicle's rear surface 18. As an example, as shown in the Fig. As shown in Figures 8-9B, a plate 54 is fixed to the rod 22 (i.e., movable as a unit with the rod 22), and the locking mechanism 44 can be in releasable engagement with the plate 54. The plate 54 can, for example, be inserted between a nut and the head 24, as in the example shown in the Fig. 8-9B shown. In such examples, the nut and the head 24 can be threaded in engagement with the rod 22.

[0068] The plate 54 can define a hole 58 that receives the rear section 50 to selectively lock the rod 22 to the flange 32. The lock 44 can be driven by inertia from the locked position, in which the rod 22 is connected to the frame member end 14, and the unlocked position, which is separated from the rod 22 and / or the frame member end 14. In particular, the lock 44 can be configured to rotate around the hinge 46 from the locked position to the unlocked position when, due to the inertia of the lock 44, it is subjected to forces associated with a vehicle impact, such as a pedestrian impact and / or a frontal vehicle impact.During an impact, a force on the bumper 20 rapidly slows the forward movement of the bumper 20, the frame carrier end 14 and the hinge 46 on the frame carrier end 14, and during this rapid deceleration, the lock 44 is caused by the inertia of the lock 44 to rotate about the hinge 46 into the unlocked position.

[0069] In the example shown in the figures, a weight 56 ​​can be present on the intermediate section to trigger the inertia-based rotation of the lock 44 about the hinge 46 in response to a force associated with a vehicle impact. In other words, the weight 56 ​​increases the moment of force about the hinge 46. In some examples, including the one shown in the Fig.In the example shown in Figure 9A-B, the weight 56 ​​can be in a slidable engagement with the intermediate section 52. In such an example, the weight 56 ​​is initially mounted on the intermediate section 52 near the rear section 50 and is slidable forward on the intermediate section 52 relative to the vehicle when subjected to a force associated with a vehicle impact. The forward movement of the weight 56 ​​on the intermediate section 52, when subjected to forces associated with a vehicle impact, causes the locking mechanism 44 to rotate around the hinge 46.

[0070] The revelation has been described in an illustrative manner, and it is understood that the terminology used is descriptive and not restrictive. In light of the foregoing teachings, many modifications and variations of the present revelation are possible, and the revelation can be implemented differently than specifically described.

Claims

[1] Vehicle, comprising: a vehicle frame having a frame beam end, wherein the frame beam end has a vehicle-forward end and a vehicle-rear end; a bumper in front of the end of the frame carrier, relative to the vehicle; a rod that supports the bumper at the frame member end, wherein the rod is fixed to the bumper and extends slidably through the vehicle-forward surface and the vehicle-rear surface of the frame member end; a head that is fixed to the rod and, in relation to the vehicle, is held behind the rear surface of the vehicle by the frame member end; and a spring on the rod, wherein the spring has a progressive nonlinear spring rate. [2] Vehicle according to claim 1, wherein the bumper is movable rearward from an extended position towards the end of the frame member relative to the vehicle, wherein the spring is loaded in the extended position between the vehicle frame and the bumper. [3] Vehicle according to claim 2, wherein the spring is elastically compressible between the frame support end and the bumper. [4] Vehicle according to claim 1, wherein the frame support end includes a base elongated along a longitudinal axis of the vehicle and a flange extending radially from the base, and the flange includes the vehicle-forward surface and the vehicle-rear surface. [5] Vehicle according to one of claims 1-4, wherein the spring comprises a front collar engaging with the rod adjacent to the bumper, a rear collar spaced apart from the rear collar along an axis of the rod and engaging with the rod adjacent to the frame member end, and a plurality of arcs extending from the front collar to the rear collar and fixed to the front collar and the rear collar. [6] Vehicle according to claim 5, wherein the front collar is in slidable engagement with the rod and the rear collar is in slidable engagement with the rod. [7] Vehicle according to claim 5, wherein the front collar is cylindrical and the rear collar is cylindrical, wherein the arcs are positioned circumferentially around the front collar and the rear collar and are elongated along the axis of the rod. [8] Vehicle according to claim 5, wherein the arcs between the front collar and the rear collar bend outwards away from the bar. [9] Vehicle according to claim 5, wherein the arches are designed to bend elastically during a pedestrian impact test and the arches are designed to deform plastically during a frontal impact test. [10] Vehicle according to one of claims 1-4, wherein the spring is a conical coil spring. [11] Vehicle according to claim 10, wherein the conical coil spring is wound around the rod. [12] Vehicle according to one of claims 1-4, further comprising a locking mechanism which detachably connects the rod to the frame support end. [13] Vehicle according to claim 12, wherein the locking mechanism is rotatably connected to the vehicle-forward surface of the frame support end, wherein the locking mechanism is in releasable engagement with the rod behind the vehicle-rear surface. [14] Vehicle according to claim 13, wherein the locking mechanism comprises a front section rotatably connected to the vehicle-forward surface, a rear section located behind the vehicle-rear surface, an intermediate section extending from the front section to the rear section, and a weight displaceable forward on the intermediate section relative to the vehicle. [15] Vehicle according to claim 12, wherein the locking mechanism is driven by inertia from a locked position in which the rod is connected to the frame support end and an unlocked position which is separated from the rod and / or the frame support end.

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