Device for determining a load on a component and method for producing such a device

Abstract

In order to provide a device (100) for determining a defined load on a component (102), in particular a component (102) of a motor vehicle, which device enables reliable detection of damage and which has a simple structural design, it is proposed that the device (100) comprises an electrically conductive device (108) which is provided at least in regions on and / or in the component (102) and whose conductivity properties can be changed by the action of an external force (F) on the component (102), wherein the defined load on the component (102) can be determined by determining the conductivity properties of the electrically conductive device (108).

Description

The present invention relates to a device for determining a defined load of a component, in particular a component of a motor vehicle, and to a method for producing such a device.Motor vehicles can have various protection devices which protect the motor vehicle or components of a motor vehicle from external influences. For example, motor vehicles can be provided with an underrun protection which, when placed on a base, protects components of the motor vehicle, e.g. a battery unit, a motor unit, a fuel cell unit or the like, from damage.The object of the present invention is to provide a device for determining a defined load of a component, by means of which a reliable detection of damage is achieved and which has a simple structural design.This object is achieved according to the invention by a device for determining a defined load of a component, comprising an electrically conductive device which is provided at least in regions on and / or in the component and whose conductivity properties can be changed by acting on the component with an external force, wherein the defined load of the component can be determined by determining the conductivity properties of the electrically conductive device.The component can be, in particular, a component or a component for a motor vehicle.The component is preferably a component for the motor vehicle which extends at least in regions in a planar manner.The component can be formed as an injection-molded part, molded part or pressed part.In particular, the component forms a protection device for the motor vehicle, for example underrun protection. Such protection devices can be provided on an underbody of the motor vehicle, in order to protect, for example, a motor unit, a battery unit, a fuel cell unit or the like from the action of external forces, for example, a contact on a subgrade, and to avoid damage.The external force corresponds in particular to a defined magnitude of an external force, by the action of which on the component damage to the component or damage to a component to be protected by the component occurs on account of deformation of the component.That is, the defined external force corresponds to a critical load of the component, at which damage to the component or damage to a component to be protected by the component occurs.Such a defined load can be determined by the electrically conductive device provided at least in regions on and / or in the component, in that the change in the conductivity properties of the electrically conductive device due to the action of the external force on the component can be determined.Reaching or exceeding the defined external force on the component can lead to a deformation or deformation of the component, as a result of which a manipulation, for example damage, of the electrically conductive device takes place, as a result of which the change in the conductivity properties is effected.In this way, it can be determined by determining the conductivity properties that at least the defined external force acts or has acted on the component.Advantageously, the manipulation, e.g. damage, of the electrically conductive device can cause an interruption of a current signal, so that the defined load of the component can be determined by the presence or absence of a current signal.It can likewise be provided that an electrical resistance of the electrically conductive device can be changed by the manipulation, e.g. damage, of the electrically conductive device, so that the defined load of the component can be determined by determining a change of the current signal relating to the electrical resistance.Preferably, the electrically conductive device can be coupled to a controller of the motor vehicle in order to output, for example, an output signal and / or a control signal on the basis of the current signal.An advantageous development of the device can provide that the electrically conductive device has at least one conductor track which is provided on and / or in the component so as to run within a surface region or extend over a surface area.In particular, the at least one conductor track on and / or in the component has any desired geometric profile.Advantageously, the at least one conductor track has a course on and / or in the component, in which at least partial sections of the conductor track run spaced apart from one another and / or distributed in the surface region.The course of the at least one conductor track can provide, in particular, that at least partial sections of the at least one conductor track run distributed over the surface region. In this way, a planar region of the component can be covered at least in regions by the at least one conductor track.The at least one conductor track of the electrically conductive device can have a line width and / or a line cross section of 20 mm or less, preferably 10 mm or less, particularly preferably 5 mm or less.Alternatively or additionally, the at least one conductor track can also be formed at least in regions as an electrically conductive line layer which extends in a planar manner and extends at least in regions on and / or in the component.The at least one conductor track of the electrically conductive device can preferably be arranged on a surface of the component, for example on a surface of the component facing the vehicle and / or on a surface of the component facing away from the vehicle.Likewise, the at least one conductor track of the electrically conductive device can be introduced into the component and / or provided in an interior space of the component.One configuration of the device can additionally provide that the at least one conductor track comprises a carrier material in which one or more electrically conductive elements are introduced, in particular carbon particles, graphite particles, metallic particles or the like.It can particularly preferably be provided that the at least one conductor track is formed by the carrier material with the one or more electrically conductive elements embedded therein.Preferably, the carrier material forms a matrix in which the one or more electrically conductive elements are embedded.The electrically conductive elements are in particular a multiplicity of electrically conductive particles, in particular carbon particles, graphite particles, metallic particles or the like.The plurality of electrically conductive particles in the carrier material and the mutual contact of the particles with one another allow the electrical conductivity of the at least one conductor track to be formed.The electrically conductive elements can have, for example, a particle size of 5 mm or less, preferably 2 mm or less, particularly preferably 1 mm or less.The electrically conductive elements can have any desired particle shape, for example they can be formed as round particles, angular particles, fragmentary particles, filament-like particles and / or the like.It can likewise be provided that one or more electrically conductive elements are designed as an electrical conductor which extends in the carrier material.In a development of the device, the at least one conductor track can be attached to the component.Preferably, the at least one conductor track can be attached to the component in that the carrier material is formed, injection-molded, glued, welded and / or the like onto the component.In particular, the carrier material is injection-molded onto a surface of the component by an injection molding method.The carrier material is preferably a plastic material, in particular a thermoplastic.Alternatively, it can likewise be provided that the at least one conductor track is formed as a prefabricated component, for example by an injection molding method, and as such can be attached to the component, for example, moldable, adhesive-bonded, weldable and / or the like.Advantageously, it can be provided that the at least one conductor track on the component is provided with a protective layer or a cover layer or is introduced into such a layer.An advantageous further development of the device can additionally provide that the at least one conductor track has a failure structure which is formed as a function of the defined load and which brings about the change in the conductivity properties when the external force acts.In particular, the failure structure of the at least one conductor track has a structural geometry which fails when the critical force acts on the component in order to interrupt the electrical conductivity of the at least one conductor track and / or to change the electrical resistance of the at least one conductor track.The failure structure can be configured to cause a failure, for example a damage or interruption, of the at least one conductor track when the defined load is reached or exceeded, as a result of which a current signal of the electrically conductive device is changed and / or interrupted.In a development of the device, the at least one conductor track can be designed as a rib, projection, elevation or the like and / or have at least one predetermined breaking point.In this case, it is provided in particular that the rib, the projection, the elevation or the like is formed on a surface of the component and / or extends thereon.The rib, the projection, the elevation or the like can be attached to a surface of the component, in particular integrally formed, injection-molded, adhesively bonded, welded on and / or the like.Particularly preferably, the rib, the projection, the elevation or the like can be formed by an injection molding process with the carrier material.By the at least one conductor track being formed as a rib, projection, elevation or the like, a geometry can be formed which, when the external force acts on the component, causes damage, for example breaking, of the at least one conductor track, as a result of which the conductivity properties of the at least one conductor track are changed.The rib, protrusion, bump, or the like may have a geometry that increases the structural strength of the component. For example, the rib, the protrusion, the elevation or the like can form a reinforcing element and / or stiffening element for the component.Advantageously, it can be provided in the device that the at least one conductor track on and / or in the component has, at least in sections, a meandering, wave-shaped, zigzag-shaped, spiral-shaped, parallel, intersecting and / or the like course.Advantageously, the electrically conductive device can comprise a plurality of conductor tracks which have a meandering, wavy, zigzag, spiral, parallel, intersecting and / or the like course on and / or in the component at least in sections.The at least one conductor track or the plurality of conductor tracks can be arranged on and / or in the component in such a way that at least partial sections of the conductor track or conductor tracks run at a distance of at least 10 mm, preferably at least 50 mm, particularly preferably at least 100 mm, and / or at a distance of at most 300 mm, preferably at most 200 mm, particularly preferably at most 100 mm, from one another.As a result of the at least one conductor track running distributed on and / or in the component in this way, a large surface area on the component can be provided with the electrically conductive device.A preferred development of the device can additionally provide that the electrically conductive device is formed on the component by an injection molding method.The component and the electrically conductive device can preferably be formed by an injection molding method, in particular by a multicomponent injection molding method.The multicomponent injection molding process can be, for example, a two-component injection molding process. In such a multicomponent injection molding process, for example a two-component injection molding process, the component can be formed from at least one first injection molding component and the electrically conductive device can be formed from at least one further injection molding component.The component and / or the electrically conductive device can consequently be formed both individually by separate injection molding methods and by a common injection molding method.According to a particularly preferred embodiment of the device, the component can form a protective element, cladding element, underrun protection, paneling element, housing element, cover element or the like for a motor vehicle.In particular, the component can be designed as an element by which any desired component of a motor vehicle can be protected from external influences and damage.Particularly preferably, the component is designed as an underrun protection for a motor vehicle.By mounting such an underride guard on an underbody of the motor vehicle, a motor unit, battery unit, fuel cell unit or the like can be protected from a base of the vehicle.The device according to the disclosure can thus determine damage to a motor unit, battery unit, fuel cell unit or the like of a motor vehicle on account of the effect of the defined external force on the component, for example on account of the motor vehicle being placed on the underlying surface, as a result of which the component experiences such a deformation that the motor unit, battery unit, fuel cell unit or the like to be protected is also damaged.The object is also achieved by a method for producing a device for determining a defined load of a component, in particular a device according to one of the embodiments described above, wherein the method has the steps: a) providing the component, in particular a component of a motor vehicle, and forming and / or arranging at least one conductor track of an electrically conductive device on the component by a carrier material being attached to the component, in particular integrally formed, injection-molded, adhesively bonded, welded and / or the like, wherein one or more electrically conductive elements, in particular carbon particles, graphite particles, metallic particles or the like, are introduced into the carrier material, or b) providing at least one conductor track of an electrically conductive device and producing the component, wherein during the production of the component the at least one conductor track is arranged on and / or in the component.The component can be formed in particular by an injection molding process.The at least one conductor track of the electrically conductive device can be formed in particular by an injection molding method.Preferably, the at least one conductor track can be injection-molded onto the component by an injection molding method.Preferably, it can be provided that the component and the at least one conductor track of the electrically conductive device are formed jointly by a multicomponent injection molding process.In this case, the component can be formed by at least one first injection-molding component, and the at least one conductor track of the electrically conductive device can be formed by at least one second injection-molding component, which comprises the carrier material or forms the carrier material in which the one or more electrically conductive elements are introduced.It can likewise be provided that the component and the at least one conductor track of the electrically conductive device are formed by separate injection molding methods and subsequently the at least one conductor track is attached to the component.However, the component and / or the at least one conductor track of the electrically conductive device is not limited to production by an injection molding method.Likewise, the component and / or the at least one conductor track of the electrically conductive device can be formed as a molded part, a pressed part or the like.The component and / or the electrically conductive device can also be composed of a plurality of such component parts.Further preferred features and / or advantages of the invention are the subject matter of the following description and the graphical representation of exemplary embodiments.The figures show: FIG. 1 shows a schematic plan view of a device for determining a defined load of a component according to an embodiment of the disclosure; FIG. 2 is a schematic sectional view of the device along the section A-A in FIG. 1.Identical or functionally equivalent elements are provided with the same reference numerals in all figures.FIG. 1 shows a schematic plan view of a device, denoted as a whole by 100, for determining a defined load of a component 102 according to an embodiment according to the disclosure, and FIG. 2 shows a schematic sectional view of the device 100 along the section A-A in FIG. 1.The component 102 can be any desired component, preferably component for a motor vehicle.Component 102 may preferably be designed as a planking element, e.g., a protective element, for a motor vehicle.In particular, the component 102 can form an underrun protection for a motor vehicle. Such a protection device can be provided on an underbody of the motor vehicle, in order to protect a motor unit, a battery unit, a fuel cell unit or the like, for example, from external influences and damage.Alternatively, the component 102 may also form a trim member, a housing member, a lid member, or the like for an automobile.The component 102 may be formed from one or more component parts.In particular, the component 102 has a base body which extends at least in regions in a planar manner.By means of such a component 102 extending in a planar manner, the underride guard for the motor vehicle can be formed, for example, in order to form a planar guard for the underbody of the motor vehicle.The component 102 can have an interior space, not shown in more detail. In such an interior space, for example, a reinforcing structure for reinforcing the component 102 may be provided.The component 102 may include a top surface 104 and a bottom surface 106. The top surface 104 of the component 102 may form a vehicle-facing side of the component 102. The bottom side 106 of the component 102 may form a side of the component 102 facing away from the motor vehicle.Component 102 is preferably formed from a plastic material, preferably from a thermoplastic.For example, the component 102 may be formed from a thermoplastic composite material.In particular, the component 102 is an injection molded component.Likewise, the component 102 can also be a mold component, a press component or the like.Alternatively, the component 102 can likewise be formed from any other material, for example from a metal, in particular light metal, composite material or the like.The apparatus 100 comprises an electrically conductive device 108 arranged on the component 102.The electrically conductive device 108 is provided to determine a defined load of the component 102. For this purpose, the electrically conductive device 108 is designed such that its conductivity properties can be changed by the action of an external force F on the component 102.On account of the action of the external force F, a change in the conductivity properties of the electrically conductive device 108 can consequently be determined, such that the defined load of the component 102 can be determined as a function of the determined conductivity properties.The electrically conductive device 108 has at least one conductor track 110 which is arranged on the upper side 104 of the component 102.Likewise, the at least one conductor track 110 of the electrically conductive device 108 can be arranged on the underside 106 of the component 102.The at least one conductor track 110 of the electrically conductive device 108 can also be arranged in an interior of the component 102 or a wall of the component 102.The conductor track 110 of the electrically conductive device 108 is arranged on the component 102 in such a way that it runs on the component 102 within a surface region 112.The surface region 112 in which the conductor track 110 of the electrically conductive device 108 runs on the component 102 can be configured in any desired manner.The surface region 112 in which the conductor track 110 of the electrically conductive device 108 on the component 102 extends preferably extends over an area of at least 50%, preferably at least 75%, of the total area of the component 102, in particular of the upper side 104 and / or lower side 106 of the component 102.The conductor track 110 can be provided within the surface region 112 in any desired course. In particular, the conductor track 110 is provided within the surface region 112 in a course which extends over a large area in the surface region 112.In particular, the conductor track 110 can be provided on the component 102 in a meandering course.Alternatively, the conductor track 110 can likewise be provided on the component 102 in a wave-shaped, zigzag-shaped, spiral-shaped, parallel, intersecting and / or similar course.Contrary to the schematic illustration shown in FIGS. 1 and 2, the electrically conductive device 108 can also comprise a plurality of conductor tracks 110, which are provided on the component 102 in such a meandering, wavy, zigzag, spiral, parallel, intersecting and / or similar course.The course of the conductor track 110 can provide that partial sections of the conductor track 110 run at a distance of at least 10 mm, preferably at least 50 mm, particularly preferably at least 100 mm, from one another.The course of the conductor track 110 can additionally provide that partial sections of the conductor track 110 run at a distance of at most 300 mm, preferably at most 200 mm, particularly preferably at most 100 mm from one another.The conductor track 110 is formed by a carrier material 114, in which electrically conductive elements 116 are introduced, which form the electrical conductivity of the conductor track 110.The electrically conductive elements 116 are in particular a multiplicity of carbon particles, graphite particles, metallic particles or the like introduced into the carrier material 114.The carrier material 114 may form a matrix for the electrically conductive elements 116.A particle size of the electrically conductive elements 116 can be 5 mm or less, preferably 2 mm or less, particularly preferably 1 mm or less.A particle shape of the electrically conductive elements 116 can have any desired geometry, for example in the form of round particles, angular particles, fragment-like particles, filament-like particles and / or the like.The electrically conductive elements 116 have a density distribution in the carrier material 114, by means of which the electrical conductivity of the conductor track 110 is formed, for example by contact between the electrically conductive elements 116 within the carrier material 114.An alternative or supplementary configuration can likewise provide that one or more electrically conductive elements 116 are formed as an electrical conductor extending in the carrier material 114.The conductor track 110 is preferably attached to the component 102 by the carrier material 114 with the electrically conductive elements 116 introduced therein being molded, injection-molded, glued, welded and / or the like onto the component 102.In particular, the conductor track 110 of the electrically conductive device 108 is formed in that the carrier material 114 with the electrically conductive elements 116 introduced therein is injection-molded onto the component 102 by an injection molding method.The carrier material 114 is at least partially formed from a plastic material, preferably a thermoplastic.In particular, the plastic is a plastic that can be processed in an injection molding process.The component 102 and the electrically conductive device 108 can be formed both individually by separate injection molding methods and continuously by a common injection molding method.The device 100 can preferably be produced by forming the component 102 and the electrically conductive device 108 by a multicomponent injection molding process, in particular a two-component injection molding process.In such a multicomponent injection molding process, the component 102 is formed from at least one first injection molding component, for example a first thermoplastic, and the electrically conductive device 108 is formed from at least one further injection molding component, for example a second thermoplastic.The at least one first and at least one second injection-molded component can be both identical materials, in particular plastics, and different materials, in particular plastics.The conductor track 110 is formed on the component 102 by the injection molding process with the carrier material 114, in particular as a rib, as an elevation, as a protrusion or the like opposite a surface of the component 102.The conductor track 110 can preferably have a height with respect to the surface of the component 102 and / or a width and / or a line cross section of 20 mm or less, preferably 10 mm or less, particularly preferably 5 mm or less.The configuration of the conductor track 110 is not limited to one of the geometries mentioned above.In particular, the geometric configuration of the conductor track 110 forms a failure structure which, when the external force F acts on the component 102, causes damage, for example at least partial breaking, to the conductor track 110.The failure structure of the conductor track 110 may comprise at least one predetermined breaking point which is designed to cause damage, e.g. at least partial breaking, of the conductor track 110 when the external force F acts on the component 102.The damage of the conductor track 110, i.e. the damage of the rib, the protrusion, the elevation or the like, or the triggering of the predetermined breaking point, depending on the defined external force F, can cause the electrical conductivity of the conductor track 110 to be interrupted and / or an electrical resistance of the conductor track 110 to be changed.The failure structure of the conductor track 110 is formed in particular as a function of the defined external force F.In other words, the action of the defined external force F on the component 102 corresponds to a defined load of the component 102. This defined load of the component 102 causes an at least partial deformation of the component 102.In this case, the defined external force F corresponds to a magnitude at which the deformation of the component 102 has a magnitude at which the damage to the conductor track 110 takes place.In particular, the defined external force F corresponds to a critical force which leads to a critical load on the component 102, which preferably just causes the damage to the conductor track 110.In this case, the critical load of the component 102 can be defined in that it leads to a critical deformation or damage of the component and / or of a component adjacent to the component 102 and to be protected by the component 102.That is, if the component 102 is designed as a protective device, in particular underrun protection, for the motor vehicle, the defined load of the component 102 and the resulting deformation of the component 102 can lead to a critical deformation or damage of the component to be protected by the protective device, for example the motor unit, the battery unit, the fuel cell unit or the like.The failure structure of the conductor track 110 is accordingly set in particular as a function of the critical external force F, such that the conductor track 110 is damaged when the critical load of the component 102 is reached or exceeded on account of the action of the critical external force F and the resulting deformation of the component 102, and as a result an interruption of the electrical conductivity of the conductor track 110 and / or a change of an electrical resistance of the conductor track 110 occurs.In other words, the device 100 is in particular a device for determining a defined or critical deformation of the component 102, which leads to a deformation and / or damage of a component, in particular a motor unit, a battery unit, a fuel cell unit or the like, of a motor vehicle, arranged adjacent to the component 102.The electrically conductive device 108 forms a circuit through the conductor track 110, to which a current signal can be applied.Preferably, the electrically conductive device 108 can comprise a controller 118 which is arranged in the circuit in order to apply the current signal and / or to determine the current signal. The controller 118 may be, for example, a vehicle controller.The circuit can be changed or interrupted by damage to the conductor track 110, so that a corresponding load on the component 102 can be determined on the basis of the changed or interrupted current signal and / or the change in the electrical resistance.Since the failure structure of the conductor track 110 is designed as a function of the defined external force F, the defined load on the component 102 can be determined when the defined external force F is reached or exceeded, on the basis of the changed or interrupted current signal and / or the change in the electrical resistance.List of reference characters100 Device 102 Component 104 Upper side 106 Lower side 108 Electrically conductive device 110 Conductor track 112 Surface region 114 Carrier material 116 Electrically conductive elements 118 Controller F External force

Claims

Device (100) for determining a defined load of a component (102), in particular component (102) of a motor vehicle, comprising an electrically conductive device (108) which is provided at least in regions on and / or in the component (102) and the conductivity properties of which can be changed by acting on the component (102) with an external force (F), wherein the defined load of the component (102) can be determined by determining the conductivity properties of the electrically conductive device (108).Device according to Claim 1, characterized in that the electrically conductive device (108) has at least one conductor track (110) which is provided on and / or in the component (102) so as to extend within a surface region (112) or so as to extend over a surface area.Device according to Claim 2, characterized in that the at least one conductor track (110) comprises a carrier material (114), in which one or more electrically conductive elements (116) are introduced, in particular carbon particles, graphite particles, metallic particles or the like.Device according to Claim 2 or 3, characterized in that the at least one conductor track (110) is attached to the component (102), in particular the carrier material (114) is integrally formed, injection-moulded, adhesively bonded, welded and / or the like onto the component (102).Device according to one of Claims 2 to 4, characterized in that the at least one conductor track (110) has a failure structure which is formed as a function of the defined load and which brings about the change in the conductivity properties when the external force (F) acts.Device according to one of Claims 2 to 5, characterized in that the at least one conductor track (110) is designed as a rib, projection, elevation or the like and / or has at least one predetermined breaking point.Device according to one of Claims 2 to 6, characterized in that the at least one conductor track (110) on and / or in the component (102) has, at least in sections, a meandering, wavy, zigzag, spiral, parallel, intersecting and / or the like course.Device according to one of the preceding claims, characterized in that the electrically conductive device (108) is formed on the component (102) by an injection moulding process, preferably the component (102) and the electrically conductive device (108) are formed by a multicomponent injection moulding process.Device according to one of the preceding claims, characterized in that the component (102) forms a protective element, cladding element, underrun protection, panelling element, housing element, cover element or the like for a motor vehicle.Method for producing a device (100) for determining a defined load of a component (102), in particular a device (100) according to one of Claims 1 to 9, having the steps: a) providing the component (102), in particular component (102) of a motor vehicle, and forming and / or arranging at least one conductor track (110) of an electrically conductive device (108) on the component (102) by a carrier material (114) being attached to the component (102), in particular integrally formed, injection-molded, adhesively bonded, welded and / or the like, wherein one or more electrically conductive elements (116), in particular carbon particles, graphite particles, metallic particles or the like, are introduced into the carrier material (114), or b) providing at least one conductor track (110) of an electrically conductive device (108), and producing the component (102), wherein, during the production of the component (102), the at least one conductor track (110) is arranged on and / or in the component (102).

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