Tension spring

Abstract

The present invention provides a tension spring (12), in particular a tailgate tension spring for a motor vehicle tailgate or a trunk lid tension spring for a trunk lid (6) of a motor vehicle (2), comprising: a spring wire having a plurality of spring coils (18) which define a spring body and a spring inner cavity; and side-slotted elongated foam blocks (22, 32, 42) arranged in the spring inner cavity for damping, attenuating or avoiding undesirable vibration sounds or humming sounds of the spring body.

Description

Technical Field

[0001] The present invention relates to a tension spring, and more particularly to a tailgate tension spring for a motor vehicle tailgate or a trunk lid tension spring for a motor vehicle trunk lid. Background Art

[0002] Regarding tailgate tension springs and trunk lid tension springs, problems that often occur in practice are that, for example, when the tailgate or trunk lid is forcefully closed, or when driving on rough roads, a sound can be clearly perceived, emitting an unpleasant vibration sound and humming sound.

[0003] Currently, there is no cost-effective solution on the market that can truly and permanently avoid such vibration sounds and humming sounds of tailgate tension springs and trunk lid tension springs. Summary of the Invention

[0004] In view of this, an object of the present invention is to provide a tension spring that can be manufactured at low cost, in which vibration or humming noise is reliably and permanently avoided, while retaining all the functions of such a tension spring.

[0005] In addition, a motor vehicle having a tailgate and a tailgate tension spring or a trunk lid and a trunk lid tension spring should also be proposed, in which under all external conditions, such vibration sounds or humming sounds can be reliably and permanently avoided, while retaining all the functions of supporting the opening and closing of the tailgate or trunk lid.

[0006] A tension spring according to the present invention, particularly a tailgate tension spring for a motor vehicle tailgate or a trunk lid tension spring for a motor vehicle trunk lid, includes:

[0007] A spring wire having multiple spring coils that define a spring body and a spring inner cavity; and

[0008] A side-grooved elongated foam block disposed in the spring inner cavity for damping, attenuating or avoiding unpleasant vibration sounds or humming sounds of the spring body.

[0009] According to a basic concept of the present invention, by disposing a side-grooved elongated foam block in the spring inner cavity, annoying vibration sounds or humming sounds that can be clearly perceived acoustically can be reliably and permanently avoided in the tension spring, so that the unpleasant vibration sounds or humming sounds normally generated when the spring body is excited can be damped or attenuated to the extent that they are no longer audible or even completely avoided.

[0010] According to another basic concept of the present invention, such an elongated foam block remains permanently in the spring inner cavity without axially migrating out of the spring inner cavity. For example, after several actuations or load changes of the tension spring, as observed in internal tests in the case of an unslotted elongated foam block disposed in the spring inner cavity, migration can occur.

[0011] The side-grooved elongated foam block disposed in the inner cavity of the spring according to the present invention can prevent (figuratively speaking) the pull spring from axially migrating out of the inner cavity of the spring due to its flexural vibration movement, thereby losing its noise reduction, noise attenuation or noise avoidance function.

[0012] According to another basic concept of the present invention, the side-grooved elongated foam block is elastically pressed between the spring coils with its outer contour and maintains its position in the inner cavity of the spring during the entire service life of the pull spring. Through the lateral slots, the foam block regions located between every two adjacent slots can be particularly advantageously pressed between the spring coils, especially engaged therein, or even protrude therefrom. In this way, the foam block can be reliably prevented from axially migrating out of the inner cavity of the spring.

[0013] By means of the side-grooved elongated foam block according to the present invention, the natural frequency of the spring body is especially shifted to a higher frequency range, and during excitation vibrations caused, for example, by rough roads (such as cobblestone roads or unpaved streets) or when forcefully closing the tailgate or trunk lid, the decay curve is significantly shortened.

[0014] Surprisingly, the pull spring with the side-grooved elongated foam block reliably and permanently damps, attenuates or completely avoids the undesirable vibration sounds or humming sounds of the spring body and does not axially migrate out of the spring body. Other seemingly promising alternatives cannot provide any reliable and permanent solution to the technical problems of the present invention, especially unslotted foam blocks with different materials, foam blocks with special shapes (such as U-shaped folded foam blocks), inner and outer guide plates, etc.

[0015] The pull spring with the side-grooved elongated foam block according to the present invention can be manufactured at low cost.

[0016] In the simplest embodiment, it is sufficient to have one or several laterally arranged slots in the foam block. Preferably, the elongated foam block is cut laterally multiple times.

[0017] The pull spring according to the present invention can be used where the vibration sounds or humming sounds of the spring body are considered to be potentially problematic, and these vibration sounds or humming sounds should be damped or attenuated in a way that is no longer audible or completely avoided.

[0018] A preferred application of the pull spring according to the present invention is as a tailgate pull spring for a motor vehicle tailgate. In this regard, the tailgate should be understood as a notchback or hatchback, or as a trunk lid pull spring for a motor vehicle trunk lid. At this time, the trunk lid in the closed state should be understood as the substantially horizontally arranged trunk lid of a sedan.

[0019] According to a further understanding of the present invention, the functional performance of the pull spring is completely maintained by the side-grooved elongated foam block disposed in the inner cavity of the spring without impairing its functionality. Especially in the case of a tailgate pull spring or a trunk lid pull spring, the opening and closing support provided by such a pull spring is maximally given.

[0020] The side-grooved elongate foam block according to the invention is dimensioned in particular such that it abuts at least locally against the radially inner side of the coil.

[0021] If, in the tensioned state of the extension spring, the foam block regions between two adjacent slots engage into the gap between adjacent coils of the spring body or project outwards therefrom beyond the contour of the spring body, and the spring is then compressed such that these regions are at least partly retained between the coils and are clamped and reliably fixed by these coils.

[0022] The extension spring according to the invention can also be referred to as a cylindrical helical spring made of round wire, oval wire, etc.

[0023] The foam block according to the invention is suitable for several foam materials. Particularly suitable foam materials are polyether foam, polyurethane foam, polyether polyurethane foam and recycled composite foam (e.g., PO 80 and POA 60).

[0024] According to a first embodiment of the invention, the lateral slots of the side-grooved elongate foam block arranged in the spring cavity are configured such that the lateral slots counteract, in particular prevent, the axial displacement of the foam block caused by the stretching and compression movements of the spring body.

[0025] According to another embodiment of the invention, the regions between the slots on at least one side of the side-grooved elongate foam block are configured such that when the spring body is stretched, these regions engage at least partly into the gap between adjacent coils or project outwards from the spring body, whereby the foam block is fixed relative to the spring body, in particular axially and / or radially, and / or counteracts the axial displacement caused by the stretching and compression movements of the spring body, in particular prevents such axial displacement.

[0026] According to yet another embodiment of the invention, the depth of the slots is at least as large as the thickness of the spring wire.

[0027] In this way, the foam block regions between two adjacent coils can engage into the gap between these coils or even "poke out" therefrom, i.e., project outwards beyond the contour of the spring body. This can particularly reliably avoid the axial displacement of the foam block.

[0028] According to still another embodiment of the invention, based on the specific length of the elongate foam block and the specific tensile load conditions of the spring body, the number of slots is matched to the number of coils and is in particular comparable thereto. In this way, all the foam block regions located between every two adjacent slots can engage into the corresponding gaps between adjacent coils or project outwards therefrom.

[0029] According to a further embodiment of the present invention, the side-grooved elongated foam block is arranged in the spring inner cavity in a laterally compressed or extruded manner to exert a force in the radial direction to weaken vibration noise or humming noise. In this way, the force for weakening vibration noise or humming noise is exerted outward in the radial direction on the spring body.

[0030] According to a further embodiment of the present invention, the cross-section of the side-grooved elongated foam block in the non-compressed state has a dimension in at least one lateral direction that is larger than the cross-section of the spring inner cavity.

[0031] In this regard, relative to the cross-section of the spring inner cavity in the non-compressed state, the side-grooved elongated foam block can be configured with an interference fit in size. This ensures that the foam block is fixed particularly reliably and permanently in the spring body and prevents the foam block from migrating out of the spring body in the axial direction in a particularly reliable manner.

[0032] According to a further embodiment of the present invention, the slots are provided in two opposite sides. In this way, the foam block can be said to be fixed to the opposite sides relative to the spring body and thus fixed particularly reliably. If slots are provided on the opposite sides of the foam block, these slots can all be arranged at the same length position. Alternatively, the slots on one side can also be longitudinally offset relative to the slots on the other side.

[0033] According to a further embodiment of the present invention, the side-grooved elongated foam block is configured as a substantially cuboid-shaped foam block, and slots are introduced in at least one of its sides, especially in its two opposite sides. The cuboid-shaped foam block can especially have a rectangular or square cross-section. Such a cuboid-shaped foam block can be made at extremely low cost, for example, by punching or stamping a strip from a prefabricated foam pad.

[0034] Alternatively, the side-grooved elongated foam block can especially have a circular, oval, elliptical or polygonal cross-section in the non-compressed state, and slots are introduced in at least one of its sides, especially in its two opposite sides.

[0035] In principle, however, any shape such as a folded shape is possible for the side-grooved elongated foam block.

[0036] According to a further embodiment of the present invention, the slots are distributed, especially evenly distributed, over most of the length, especially the entire length, of the side of the side-grooved elongated foam block.

[0037] In this way, the side regions can respectively engage into the corresponding gaps between adjacent spring coils at several positions of the extension spring between two adjacent slots, and thus the foam block can be fixed to the spring body particularly reliably and permanently, and the foam block can be particularly reliably prevented from migrating axially out of the spring body.

[0038] According to a further embodiment of the invention, the distance between every two adjacent slots of the foam block is substantially equivalent to the distance between every two adjacent spring coils of the tension spring in the tension load state.

[0039] In this way, the side regions can be respectively joined to the corresponding gaps between adjacent spring coils at several positions of the tension spring between two adjacent slots, and thus a particularly reliable and permanent fixation of the foam block relative to the spring body can be achieved, and the foam block can be particularly reliably prevented from axially shifting out of the spring body.

[0040] According to a further embodiment of the invention, the slots are transverse to, in particular substantially orthogonal to, the side surface of the side-slotted elongated foam block.

[0041] Alternatively, the slots can be arranged obliquely with respect to the side surface of the side-slotted elongated foam block.

[0042] The slots can be configured as straight cuts or notches without material loss, and / or the slot sides of the slots can at least partially abut against each other in the unloaded state.

[0043] The slots can be configured as cuts or notches introduced into the side surface with a constant width.

[0044] For all such slot configurations, the regions of the foam block located between the slots are reliably joined to the gaps between adjacent spring coils or protrude beyond the outer contour of the spring body, and ensure a reliable and permanent fixation of the foam block relative to the spring body and prevent the foam block from axially shifting out of the spring body.

[0045] According to a further embodiment of the invention, the region between every two adjacent slots of each side is configured in a hump shape or a cuboid shape, and the hump surface or the cuboid surface is substantially located in the side surface.

[0046] According to a further embodiment of the invention, the side-slotted elongated foam block has a serrated side profile on at least one side, in particular two opposite sides, which has indentation-shaped slots with a width narrowing in the depth direction and protrusions arranged between every two adjacent slots, in particular with a serrated cross-section.

[0047] Even with such a serrated side profile, the serrated protrusions are all joined to the gaps between adjacent spring coils or protrude outward from these spring coils beyond the outer contour of the spring body, and ensure the reliable fixation of the foam block within the spring body and prevent the foam block from axially shifting out of the spring body.

[0048] According to a further embodiment of the invention, at least one end section, in particular two end sections, of the side-slotted elongated foam block without slots is particularly configured in a cuboid shape

[0049] Alternatively, the slots or the side profile can extend over the entire length of the foam block.

[0050] According to a further embodiment of the present invention, the length of the side-grooved elongated foam block is calibrated to be less than the length of the spring body in the unloaded state of the tension spring or in the state L1 of the tension spring. It has been shown in practice that a foam block having a length less than the length of the spring body in the unloaded state of the tension spring or in the state L1 of the tension spring works particularly well, that is, it particularly effectively damps or attenuates or even completely avoids vibration sounds or humming sounds.

[0051] Alternatively, the length of the side-grooved elongated foam block may be approximately equivalent to the length of the spring body in the unloaded state of the tension spring or in the state L1 of the tension spring.

[0052] According to a further embodiment of the present invention, the side-grooved elongated foam block is completely introduced into the spring cavity of the tension spring such that the two end faces of the side-grooved elongated foam block are located within the spring cavity of the tension spring.

[0053] According to a further embodiment of the present invention, the tension spring is configured as a tailgate tension spring or a trunk lid tension spring, which has a first spring end for connecting to a body-side connection point of a motor vehicle and a second spring end for connecting to a tailgate-side or trunk lid-side connection point of the motor vehicle.

[0054] The present invention also relates to a motor vehicle having a tailgate or a trunk lid, wherein a tailgate tension spring or a trunk lid tension spring of the above type is hinged to the body-side connection point of the motor vehicle at its first spring end and hinged to the tailgate-side or trunk lid-side connection point of the motor vehicle at its second spring end to support the opening and / or closing movement of the tailgate or the trunk lid of the motor vehicle and to damp, attenuate or avoid the adverse vibration sounds and humming sounds of the spring body.

[0055] All the advantages and embodiments given above for the tension spring apply to this motor vehicle in the same way and will not be repeated here.

[0056] In such a motor vehicle, the vibration sounds and humming sounds of the spring body are damped or attenuated by the side-grooved elongated foam block according to the present invention to such an extent that they are no longer audible or even completely avoided. At the same time, the tension spring according to the present invention maximally ensures the opening and closing support.

[0057] The present invention also relates to the use of a tailgate tension spring or a trunk lid tension spring of the type described herein in a motor vehicle, which serves as a damping element and prevents the foam block from axially shifting within its spring cavity or from slipping out thereof, thereby permanently damping, attenuating or avoiding the adverse vibration sounds or humming sounds of the spring body.

[0058] Tests have shown that particularly good results can be obtained if the foam block is introduced into the spring cavity only immediately before the tension spring is actuated. If the foam block is introduced into the spring cavity and the actuation of the spring occurs only after the introduction, less good results are obtained.

[0059] The side-grooved elongated foam block according to the present invention can be made of several different materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0061] Figure 1 A schematic partial view showing a motor vehicle 2 having a vehicle body 4 and a trunk lid 6 is shown;

[0062] FIG. 2(a) shows a schematic perspective view of a first side-grooved elongated foam block 22;

[0063] FIG. 2(b) shows a side view of the tension spring 12 in its loaded state L1;

[0064] FIG. 2(c) shows a cross-sectional view along the longitudinal symmetry plane taken along A-A in FIG. 2(b), with the tension spring 12 in FIG. 2(b) having the foam block 22 in FIG. 2(a) inserted into its spring cavity;

[0065] FIG. 3(a) shows a schematic perspective view of a second side-grooved elongated foam block 32;

[0066] FIG. 3(b) shows a side view of the tension spring 12 in its loaded state L1;

[0067] FIG. 3(c) shows a cross-sectional view along the longitudinal symmetry plane taken along B-B in FIG. 3(b), with the tension spring 12 in FIG. 3(b) having the foam block 32 in FIG. 3(a) inserted into its spring cavity;

[0068] FIG. 4(a) shows a schematic perspective view of a third side-grooved elongated foam block 42;

[0069] FIG. 4(b) shows a side view of the tension spring 12 in its loaded state L1;

[0070] FIG. 4(c) shows a cross-sectional view along the longitudinal symmetry plane taken along C-C in FIG. 4(b), with the tension spring 12 in FIG. 4(b) having the foam block 42 in FIG. 4(a) inserted into its spring cavity. DETAILED DESCRIPTION OF THE INVENTION

[0071] Figure 1 A schematic partial view showing a motor vehicle 2, in particular a sedan, having a vehicle body 4 and a trunk lid 6 is shown. Figure 1 Generally, the vehicle body 4 includes the rear half portion including the trunk lid 6.

[0072] The trunk lid 6 is pivotally attached to the body 4 via a bracket 8 at a hinge point 10 and can be Figure 1It pivots between the shown closed position and an open position (not shown), where it is conceivable that the trunk lid 6 pivots upwards. To support the opening and / or closing movement, a tension spring is provided, in particular the trunk lid tension spring 12, which is arranged between a body-side connection point 14 and a trunk-lid-side connection point 16.

[0073] In this example, the trunk-lid-side connection point 16 of the trunk lid tension spring 12 is located on the bracket 8 near the hinge point 10.

[0074] Alternatively, it is conceivable for a motor vehicle with a fastback or hatchback rear end, whose tailgate can pivot in a similar manner between a closed position and an open position and is supported in its opening and / or closing movement by a tailgate tension spring. The tailgate tension spring is similarly arranged between a body-side connection point and a tailgate-side connection point, in particular on the tailgate bracket.

[0075] The side-slotted elongated foam block 22 shown in Fig. 2(a) has an elongated cuboid basic shape and is in particular cut out from a prefabricated foam mat.

[0076] Slots 24 are introduced across its top side and across its bottom side, in particular designed without material peeling so that their opposite sides abut against each other. The depth of these slots 24 is at least as large as the thickness of the spring wire of the tension spring 12, as can be seen in Figs. 2(b) and 2(c).

[0077] When viewed from the side, the regions 26 between every two adjacent slots 24 on the top side and the bottom side of the foam block 22 have a hump shape. The slots 24 are in particular introduced equidistantly into the top side and the bottom side of the foam block 22, in particular distributed equidistantly thereon.

[0078] In this non-limiting embodiment, the width of the end section 28 corresponds to the width of the hump-shaped region 26 between two adjacent slots.

[0079] In Fig. 2(a), the foam block 22 is shown in an uncompressed state. In this uncompressed state, the foam block 22 is configured with an interference with respect to the cross-sectional dimensions of the spring inner cavity of the tension spring 12. In other words, the lateral dimensions and / or the dimensions in the height direction of the foam block 22 are larger than the cross-section of the spring inner cavity.

[0080] In Fig. 2(b), it can be clearly seen the helical spring with its body-side connection point 14, its trunk lid or tailgate side connection point 16 and its several spring coils 18. To manufacture the tension spring 12, the spring wire is wound into multiple spring coils 18. These spring coils 18 define a spring body and a spring inner cavity.

[0081] In FIG. 2(b), the tension spring 12 is shown in a slightly pre-tensioned state, i.e., a slightly stretched state L1. In this case, there is a gap 20 between every two adjacent spring coils 18. When the tension spring 12 is loaded, i.e., the two connection points 14 and 16 are pulled apart, the length of the tension spring 12 increases, and the pitch of the spring coils 18 and the width of the gap 20 also increase.

[0082] The load state L1 of the tailgate or trunk lid opening and the tension spring 12 of the tailgate or trunk lid being only slightly pre-tensioned is such that the tension spring is pre-tensioned especially to the extent that the tailgate or trunk lid can be held open.

[0083] This state L1 is different from the non-pre-tensioned state not shown in this figure, in which each adjacent spring coil 18 abuts against each other.

[0084] In the load state L2 of the tailgate or trunk lid tension spring 12 not shown in this figure, it is fully pre-tensioned, and the distance between each adjacent spring coil 18 is the largest. In this state L2, the tailgate or trunk lid is closed, and the opening assist for opening the tailgate or trunk lid from this state L2 is the greatest.

[0085] In FIGS. 2(b) and 2(c), FIGS. 3(b) and 3(c), and FIGS. 4(b) and 4(c), the tension spring 12 is shown in its loaded state L1.

[0086] In FIG. 2(c), the side-grooved elongated foam block 22 in FIG. 2(a) has now been inserted into the spring inner cavity of the tension spring 12 in FIG. 2(b). It can be clearly seen that in the L1 state of the tension spring 12, the length of the foam block 22 is less than the length of the spring body. The end face of the left end section 28 is at the level separated from the foremost coil 18 of the tension spring 12, and similarly, the end face of the right end section 28 is at the level separated from the rearmost coil 18 of the tension spring 12. The foam block 22 is inserted into the inner cavity of the tension spring 12 in a manner that completely fills the cross-section of the spring inner cavity. It can be clearly seen from FIG. 2(c) that the foam block 22 abuts against the radially inner side of the spring coil 18 with its bottom side and top side (and with its front side and back side (not visible in the cross-sectional view of FIG. 2(c))).

[0087] In the non-compressed state according to FIG. 2(a), the dimensions of the foam block 22 in the lateral and height directions are larger than the cross-section of the spring inner cavity. In other words, in the non-compressed state, the dimensions of the foam block 22 have an interference with respect to the cross-section of the spring inner cavity. If the tension spring 12 then enters from state L1 to state L2 at this time, i.e., is pulled apart until the distance between two adjacent slots 24 is equivalent to the distance between two spring coils 18, then the spring coils 18 engage into the slots 24, and the region 26 therebetween fills the gap 20 between the adjacent spring coils 18, or even extends slightly beyond the outer contour of the spring body.

[0088] This effect is particularly evident in the corner regions of the foam block 12 having a rectangular or oblong cross-section.

[0089] When the draw spring 12 is then closed in the state L1 according to FIG. 2(c), the region 26 remains at least partially in the gaps 20 between each adjacent spring coil 18 or projects radially beyond the profile of the spring coil.

[0090] The foam block 22 damps and attenuates the poor vibration sounds or humming noises of the spring body to such an extent that they are no longer audible or are even completely avoided.

[0091] By engaging the region 26 between the slots 24 into the gaps 20 between adjacent spring coils 18 or projecting outwards therefrom, the foam block 22 is axially fixed and in particular radially fixed relative to the spring body. In this way, the axial play caused by the stretching and compression movements of the spring body can be reliably counteracted, in particular this axial play can be completely prevented.

[0092] The foam block 32 in FIG. 3(a) substantially corresponds to the foam block 22 in FIG. 2(a), the difference being that the slots 24 are designed wider such that the sides of the slots 24 are spaced from each other.

[0093] In the foam block 22 of FIG. 2(a) and the foam block 32 of FIG. 3(a), the slots are transverse to, in particular substantially orthogonal to, the top and bottom sides of the foam blocks 22, 32 and extend over the entire width of the foam blocks 22, 32.

[0094] The slots 24 can also be referred to as incisions or notches and have a constant width up to their bottom. The opposite sides of the slots 24 are spaced from each other in the unloaded state.

[0095] The draw spring 12 in FIG. 3(b) corresponds to the draw spring 12 in FIG. 2(b) and will not be described in detail here. The same reference signs are used for the same features.

[0096] In the draw spring 12 of FIG. 3(c), the foam block 32 is again introduced into the spring inner cavity. The number of slots 24 in the top and bottom sides of the foam block 32 is different in the illustration of FIG. 3(c) from that in the illustration of FIG. 3(a), but only for reasons of illustration.

[0097] The draw spring 12 with the foam block 32 inserted therein in FIG. 3(c) substantially corresponds to the draw spring 12 with the foam block 22 inserted therein in FIG. 2(c). Reference can thus be made to the content of the previous figures here and will not be described in detail. The same reference signs are used for the same features.

[0098] Different from the foam block 22, it can be clearly seen from FIG. 3(c) that in the foam block 32, the width of the slots 24 matches the width of the spring wire. In this way, the spring coils 18 can be engaged particularly well into the slots 24.

[0099] The foam block 42 shown in Fig. 4(a) has serrated side profiles on both its top side and its bottom side, which have indentation-like slots 44 with widths that narrow in the depth direction, and have protrusions 46 with serrated cross-sections between two adjacent indentation-like slots 44.

[0100] Likewise, the indentation-like slots 44 and the areas between them, which are configured here as serrated protrusions 46, extend across the entire width of the foam block 42.

[0101] The end section 28 of the foam block 42 is configured without slots and is especially in the shape of a cuboid.

[0102] The tension spring 12 in Fig. 4(b) corresponds to the tension spring 12 in Figs. 2(b) and 3(b), and will not be elaborated here. The same features are marked with the same reference numerals.

[0103] In Fig. 4(c), the foam block 42 is inserted into the spring inner cavity of the tension spring 12 again. The serrated side profiles of the top side and the bottom side of the foam block 42 can be clearly seen. Likewise, the foam block 42 only occupies a part of the length of the spring inner cavity, but when observed from the cross-section, its end section 28 and its serrated protrusions 46 completely fill the spring. If the tension spring 12 is pulled open from the state L1 shown in Fig. 4(c) and enters the state L2 at this time, the serrated protrusions 46 engage into the gaps 20 between every adjacent spring coil 18 or even protrude outwards beyond the outer profile of the spring body. They at least partially remain in these gaps, even if the tension spring 12 is subsequently brought back to the state L1 shown in Fig. 4(c).

[0104] When observed from a rectangular or square cross-section, this effect is particularly significant in the corner regions of the serrated protrusions 46 and the end section 28.

[0105] In this way, the foam block 42 is axially fixed relative to the spring body and especially radially fixed. The axial wandering of the foam block 42 caused by the stretching and compression movements of the spring body is counteracted, especially completely prevented. In this way, the vibration sound or humming sound of the spring body is damped or weakened to the extent that it is no longer audible or even completely avoided.

[0106] List of reference numerals

[0107] 2 Motor vehicle

[0108] 4 Vehicle body

[0109] 6 Trunk lid

[0110] 8 Trunk lid bracket

[0111] 10 Body side hinge point

[0112] 12 Tension spring

[0113] 14 Body side connection point

[0114] 16 Trunk lid side connection point

[0115] 18 Spring coil

[0116] 20 Gap

[0117] 22 First slotted rectangular foam block

[0118] 24 Slot

[0119] 26 Hump-shaped area between slots

[0120] 28 End segment

[0121] 32 Second slotted rectangular foam block

[0122] 42 Third slotted rectangular foam block

[0123] 44 Dented slot

[0124] 46 Serrated protrusion

Claims

1. A motor vehicle (2), comprising: A tailgate or trunk lid (6); and A tension spring (12) configured as a tailgate tension spring for a motor vehicle tailgate or a trunk lid tension spring for a motor vehicle trunk lid (6), wherein the tension spring (12) is characterized in that: A spring wire having multiple spring coils (18), the spring coils (18) defining a spring body and a spring inner cavity; and Side-grooved elongated foam blocks (22, 32) disposed in the spring inner cavity for damping, reducing or avoiding undesirable vibration sounds or humming sounds of the spring body; wherein the side-grooved elongated foam blocks (22, 32) are disposed in the spring inner cavity in a laterally compressed or squeezed manner to exert a force for reducing vibration sounds or humming sounds outward in the radial direction; wherein the side-grooved elongated foam blocks (22, 32) are configured as substantially cuboid foam blocks (22, 32), with slots (24) introduced in two opposite side surfaces thereof, and wherein the slots (24) are disposed perpendicular to the surface or side surface of the side-grooved elongated foam blocks (22, 32); wherein the region (26) between each adjacent pair of slots (24) on each side surface is configured as a cuboid shape, and the cuboid surface is substantially located in the side surface; and wherein the tension spring (12) is hinged to a body-side connection point of the motor vehicle (2) at its first spring end (14) and hinged to a tailgate or trunk lid-side connection point of the motor vehicle (2) at its second spring end (16) to support the opening and / or closing movement of the tailgate or trunk lid (6) of the motor vehicle (2) and to damp, reduce or avoid undesirable vibration sounds and humming sounds of the spring body.

2. The motor vehicle (2) according to claim 1, Among them, The lateral slots (24) of the side-grooved elongated foam blocks (22, 32) disposed in the spring inner cavity are configured such that the lateral slots (24) counteract the axial displacement of the foam blocks (22, 32) caused by the stretching and compression movements of the spring body.

3. The motor vehicle (2) according to claim 1 or 2, Among them, The region between the slots (24) on at least one side surface of the side-grooved elongated foam blocks (22, 32) is configured such that when the spring body is stretched, the region at least partially engages into the gap (20) between adjacent spring coils (18) or protrudes outward from the spring body, whereby the foam blocks (22, 32) are axially and / or radially fixed relative to the spring body and / or counteract the axial displacement caused by the stretching and compression movements of the spring body.

4. The motor vehicle (2) according to claim 1 or 2, Among them, The depth of the slots (24) is at least as large as the thickness of the spring wire.

5. The motor vehicle (2) according to claim 1 or 2, Among them, The cross-sectional dimension of the side-grooved elongated foam blocks (22, 32) in at least one lateral direction when in an uncompressed state is larger than the cross-section of the spring inner cavity.

6. The motor vehicle (2) according to claim 1 or 2, Among them, The slots (24) are distributed over most of the length of the side surfaces of the side-grooved elongated foam blocks (22, 32).

7. The motor vehicle (2) according to claim 6, Among them, wherein the slots (24) are equidistantly distributed over the entire length of the side of the side-slotted elongate foam blocks (22, 32).

8. The motor vehicle (2) according to claim 1 or 2, Among them, wherein the distance between every two adjacent slots (24) of the foam blocks (22, 32) is substantially equivalent to the distance between every two adjacent spring coils (18) of the tension spring (12) in a tension-loaded state.

9. The motor vehicle (2) according to claim 1 or 2, Among them, wherein the slots are configured as straight cuts (24) or notches without material loss, and / or the slot sides of the slots (24) are at least partially in contact with each other in a non-loaded state; or wherein the slots are configured as cuts (24) or notches introducing sides with a constant width.

10. The motor vehicle (2) according to claim 1, Among them, wherein at least one end section (28) of the side-slotted elongate foam blocks (22, 32) without slots (24) is configured in a cuboid shape; or wherein the slots extend over the entire length of the foam blocks.

11. The motor vehicle (2) according to claim 10, Among them, wherein the at least one end section (28) is two end sections (28).

12. The motor vehicle (2) according to claim 1 or 2, Among them, wherein the length of the side-slotted elongate foam blocks (22, 32) is calibrated to be less than the length of the spring body of the tension spring (12) in an unloaded state or in the state L1 of the tension spring (12); or wherein the length of the side-slotted elongate foam blocks is substantially equivalent to the length of the spring body of the tension spring (12) in an unloaded state or in the state L1 of the tension spring (12).

13. The motor vehicle (2) according to claim 1 or 2, Among them, wherein the side-slotted elongate foam blocks (22, 32) are fully inserted into the spring inner cavity of the tension spring (12) such that the two end faces of the side-slotted elongate foam blocks (22, 32) are within the spring inner cavity of the tension spring (12).

14. The motor vehicle (2) according to claim 1 or 2, Among them, wherein the tension spring (12) serves as a damping element and prevents the foam blocks (22, 32) from axially shifting within its spring inner cavity or from coming out of it.

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