Folded tactile sensor

Abstract

The invention relates to a tactile sensor (10), having electric contacts (6), and having a carrier which holds the contacts (6) in a predefined arrangement and which is elastically deformable such that the contacts (6) are movable relative to one another between a first position, in which they touch, and a second position, in which they are separated from one another. According to the invention, the carrier has a preloaded, prestretched elastic planar element (1), which is fixedly connected to a support structure (2) and after relaxation automatically assumes a three-dimensional shape determined by the support structure (2).

Description

[0001] Folded tactile sensor

[0002] Description:

[0003] The invention relates to a tactile sensor according to the preamble of claim 1.

[0004] Such sensors are known in practice in various designs. For example, in the form of a switch strip designed as an opener and having a series of electrical contacts held together under pretension, for example by being threaded onto an elastic, stretched band. Due to the stretching of the band, it automatically contracts again after the electrical contacts have been installed and brings adjacent contacts into contact with one another. When a force acts on the switch strip transverse to the longitudinal direction, adjacent contacts are separated from one another and a quiescent current that would otherwise flow through the touching contacts is interrupted. Furthermore, a switch strip is known that is designed as a makeer and has two elongated contacts on an elastically deformable carrier that extend over the length of the switch strip.When a force acts on the safety edge perpendicular to its longitudinal direction, the two contacts are brought into contact, allowing a current to flow through them. The safety edges mentioned above are used in the field of safety technology, and the respective change in the switching state of the normally closed and normally closed contacts can be used either directly, e.g., by interrupting the power supply, or indirectly, e.g., with the aid of an evaluation circuit, to emit an alarm signal and / or to slow down and / or completely deactivate the drive of a moving element.

[0005] The invention is based on the object of improving a generic tactile sensor in such a way that it can be produced in many different designs in the most cost-effective manner and with the lowest possible weight, for example with different dimensions and / or with different triggering forces, and wherein the sensor is particularly robust against point-acting mechanical loads and has a high response sensitivity in the case of surface-acting mechanical loads.

[0006] This object is achieved by a sensor having the features of claim 1 and by the use of a 4D textile according to claim 21. Advantageous embodiments are described in the subclaims.

[0007] A first aspect of the invention relates to a tactile sensor, with electrical contacts, and with a carrier which holds the contacts in a predetermined arrangement and which is elastically deformable in such a way that the contacts are movable relative to one another between a first, touching position and a second, separated position, wherein the carrier has a tensioned, pre-stretched elastic surface element which is firmly connected to a support structure and, after relaxation, is automatically brought into a three-dimensional shape determined by the support structure.

[0008] In other words, the invention proposes using an elastic surface element, for example a film or a textile material such as a woven, knitted or warp-knitted fabric, as a carrier for the electrical contacts of the tactile sensor, and first stretching this surface element, either in one direction or in two directions, for example in two directions running transversely to each other. The stretching occurs in the elastic region of the surface element, so that after stretching, when the forces causing the stretching subside, it automatically strives to return to its original dimensions. In the stretched state, the surface element is firmly connected to a support structure. Only after this connection is the surface element relieved of stress, so that it then automatically contracts. The support structure constrains the surface element in such a way that the surface element automatically folds.Interruptions or weakening lines, e.g., with reduced material cross-sections, between individual sections of the support structure act as hinge lines that determine the type of folding. The folding process generally occurs automatically due to the restoring forces acting in the sheet material, i.e., without the influence of additional external forces. However, external forces can be applied to initiate the folding process, for example, if an initial deformation resistance of the support structure must be overcome, or external forces can be applied to determine the folding direction at a hinge line.

[0009] The design of the support structure with regard to the arrangement, shape, and rigidity of individual sections of the support structure enables a prediction of the shape the folded surface element will have, as well as the folding process and how the surface element is likely to behave when the load is removed, so that a desired three-dimensional shape can be predetermined. In a process known as "seif assembly," the desired three-dimensional structure can actually emerge in one design when the surface element is pulled together without any further external influence.Alternatively, certain folding processes of certain parts of the surface element provided with the support structure can be determined by external forces, either by corresponding manual reworking, for example in the case of smaller quantities, or by moving the surface element provided with the support structure in a certain conveying direction and along guide surfaces which effect the desired folding processes in the respective desired folding direction.

[0010] For example, individual point-like peaks or domes can be created, or elongated ribs that run straight, curved, or seemingly randomly. This makes it possible to create a carrier for the contacts of a tactile sensor that is very lightweight and virtually scalable in terms of dimensions, since an elastic two-dimensional surface element is economically available by the meter and simply needs to be cut to size and fitted with the relevant elements of a support structure.

[0011] The ability to produce a tactile sensor with very small dimensions enables its use in applications where the sensor should be as invisible as possible or not at all for optical reasons, for example in the furniture sector as a switch for a light that is to be switched on when a door is opened, or as a protective device against shearing and crushing edges on furniture, e.g., on extendable and retractable screens or height-adjustable desks.

[0012] On the other hand, sensors with deliberately large dimensions can also be manufactured at low cost. This allows, for example, tactile sensors in the field of safety technology to be mounted on moving elements that allow for a comparatively large overtravel. Moving elements used in industry and logistics, such as robot arms and vehicles, especially autonomous vehicles, can be equipped with such tactile sensors. In this case, the sensors are arranged at the front of the moving element in the direction of movement, so that they are the first to come into contact with an obstacle, before the moving element itself comes into contact with the obstacle.The greater the distance between the triggering surface of the tactile sensor and the moving element itself, the more time remains for the moving element to slow down between the triggering surface of the tactile sensor and the moving element itself.

[0013] The low weight and easy deformability allow the sensor according to the invention to be adapted to components of different shapes. The low weight of the sensor can be particularly advantageous when the moving component performs a pivoting movement rather than a linear movement, as is the case with a robot arm: with increasing distance from the pivot axis, a given weight results in an increasingly larger moment of inertia, which counteracts the acceleration of the moving component. The distance to the pivot or pivot point is factored into the calculation of this moment of inertia quadratically, so that weight savings on the sensor are particularly advantageous in this or similar applications.A tactile sensor, which serves to decelerate the moving component as quickly as possible in the event of a collision, is usually located at the outer end of the component, for example, the robot arm, and thus at the maximum distance from the pivot or swivel point. Unlike with a linearly moving component, such as an autonomous industrial truck, a weight reduction of the sensor at the free end of the pivoting robot arm has a disproportionately strong advantage.

[0014] The above-mentioned distance between the trigger surface of the tactile sensor and the movable element itself is referred to as the overtravel, which can be used to decelerate the movable element to a safe speed level or even to a standstill before it comes into contact with the obstacle and can cause damage to property or personal injury. A sensor according to the invention can be designed in such a way that it can be compressed flat from its unfolded three-dimensional shape, so that it has an integrated overtravel. In addition, constructive measures regarding the installation position of the sensor can create an overtravel in a manner known per se, for example by using compressible elements such asElastomer hollow profiles, foam rubber profiles, spring-loaded dampers, or the like support the sensor, so that after the sensor is triggered, the distance available for compression of the respective element forms the aforementioned overtravel, which can be used to reduce the speed of the moving element. Due to the inventive design of the sensor and the overtravel integrated therein, a longer overtravel can be provided while using the compressible elements unchanged, or the compressible elements can be made smaller or, if necessary, eliminated entirely.

[0015] The elastic surface element makes the sensor robust in that it enables a very high number of load cycles, e.g., by acting as a hinge that allows the tactile sensor to deform upon contact with an obstacle and always provides the restoring forces to return the sensor, for example, after being compressed flat, to its three-dimensional shape. Furthermore, this deformability also makes the sensor insensitive to applied point loads, making it robust in this respect as well. Despite this insensitivity to the risk of mechanical damage, the sensor exhibits a high level of sensitivity in terms of response behavior, i.e., the triggering of a switching process upon mechanical contact with an obstacle.The deformability of the sensor allows the electrodes to be arranged in such a way that after only a short deformation path, the electrodes trigger a switching process by being separated from each other in the case of an open contact or by coming into contact with each other in the case of a closer contact.

[0016] The elastic surface element represents a cost-effective base body for the three-dimensionally folded sensor, so only different support structures need to be used to create sensors of different sizes or folds. The support structures themselves can be manufactured with little effort in terms of quantity and processing of the material used, which supports the cost-effective manufacturability of the sensor – also in terms of different sensor variants.

[0017] The elastic surface element can also be used to mount the sensor: Due to its elastic extensibility, the appropriately sized surface element can extend beyond the sensor and, for example, form an annular sleeve that can be slipped over a moving component such as a robot arm, allowing the sensor to be mounted to the robot arm using this sleeve. In this way, the sensor can be mounted on components of different sizes or shapes without the need for specially adapted rigid mounting or connecting components such as mounting rails or the like, making installation simple and cost-effective. Furthermore, this reduces the number of components required for assembly, which has a positive impact on procurement and storage costs.

[0018] The elastic surface element therefore also enables the sensor to be mounted in locations that would otherwise be difficult to access. For example, if the surface element is pulled over a joint as an elastic sleeve, the joint remains flexible, whereas rigid mounting or connection components could potentially restrict this flexibility, making it impossible to mount the sensor in that location.

[0019] An anti-slip coating on the surface element and / or the movable component can ensure that the sensor stays in place and remains in the desired position during normal use of the movable component. However, in the event of a collision with an obstacle, the holding forces of the sleeve on the component can be exceeded, causing the sensor to not only trigger a switching signal but also be displaced. This can help prevent permanent damage to the sensor, potentially avoiding the need for repair or replacement.

[0020] Due to its deformability, the surface element can be turned inside out when it forms a ring- or tube-like sleeve, so that the inside and outside are swapped. This can be used to move initially external electrical contacts into a better protected position on the inside of the sleeve, so that the surface element forms an outer protective layer to protect the contacts from dirt and moisture. Sensor installation can also be made easier because the sleeve does not have to be pulled linearly onto a moving component, but can instead be rolled onto the component and thus turned inside out. This is particularly advantageous if the sleeve fits snugly against the moving component to ensure that the sensor maintains its position.In addition, unlike a linear sliding movement, the rolling motion prevents internal electrical contacts facing the moving component from rubbing against the component, which could cause premature wear of the contacts.

[0021] The sensor can be installed in a safety component mounted on the moving element, for example, in the form of a bumper made of an elastomer material, which can be designed, in particular, as a deformable hollow profile. If the sensor is installed at the front of the safety component in the direction of movement, i.e., at a distance from the moving element, the response times for triggering the sensor upon contact with an obstacle are short, and the dimensions of the safety component allow for the greatest possible overtravel. Alternatively, the sensor can also be installed at the rear of the safety component, so that the safety component, positioned upstream of the sensor in the direction of movement, offers the highest possible mechanical protection for the sensor.

[0022] However, the design of the tactile sensor with the aforementioned deliberately large structural dimensions in favor of a follow-up travel means that, compared to differently designed sensors, a sensor according to the invention can be designed significantly smaller. The comparatively large, integrated deformation travel of the sensor, which can be practically pressed flat due to its three-dimensionally unfolded shape, already offers a larger follow-up travel, even with the same cross-sectional dimensions, than sensors in which rigid elements can be pushed apart but not compressed. Compared to sensors that are conventional openers equipped with movable but inherently rigid contact elements, the sensor according to the invention changes its shape considerably more.

[0023] In one embodiment, it can be provided that the surface element is designed as a textile material.

[0024] The surface element can be designed not as a film, but as a textile fabric. The high elasticity that textiles can exhibit can result, firstly, from the extensibility of the fibers used – monofilaments or yarns – and secondly, from the three-dimensional structure of the intersecting fibers. A textile fabric therefore enables a long service life of the surface element as a carrier of the electrical sensor contacts through a correspondingly high number of actuation cycles. The high elasticity also ensures, through high restoring forces, that the sensor reliably returns to its original position after being triggered. The porous structure of the textile further facilitates a firm connection to the support structure by means of a positive connection, without having to create holes or cuts in the surface element, thus reducing the risk of cracking and reliably achieving the aforementioned longest possible service life.

[0025] In one embodiment, it can be provided that the surface element is designed as jersey, in particular as single jersey.

[0026] The elastic extensibility of the surface element can be ensured by using suitable stretchable materials, e.g., a stretchable film or, in the case of textiles, by using stretchable fibers. In one embodiment, the surface element is designed as a knitted textile, e.g., in the form of a jersey, and in particular as a single jersey, since this textile structure exhibits high extensibility. In one embodiment, the contacts can be sewn to the surface element.

[0027] The electrical contacts can be connected to the elastic surface element in various ways, e.g., by adhesive bonding, or by heat or ultrasonic welding. In one embodiment, the contacts are sewn to the surface element. This represents a material-appropriate connection method for textiles, making it particularly advantageous when a textile is used as the carrier.

[0028] In one embodiment, it can be provided that the contacts are fastened to the support structure, for example in combination with contacts which are sewn to the surface element, or alternatively thereto.

[0029] In another embodiment, the electrical contacts are attached to the support structure and / or are formed by electrically conductive sections of the support structure. Since the support structure has a significantly higher deformation resistance compared to the elastic surface element, e.g., it is less extensible, the contacts can be attached to it particularly reliably if they themselves are also only deformable to a limited extent and, e.g., are designed not as electrically conductive threads, but as flat elements, molded parts, or the like. For example, the contacts can be made of a metallic alloy or a plastic material containing electrically conductive particles.

[0030] If the electrical contacts are attached to the support structure and / or are configured as electrically conductive sections of the support structure, the most secure contacting possible between adjacent electrical contacts can be supported by the support structure having adjacent elements that are movable relative to one another and that are configured as contact carriers where they make electrical contact. For example, such contact carriers can be wider than the adjoining regions of the support structure in order to ensure secure, reliable contacting of the two separate, but electrically connected sections of the support structure through correspondingly large-area contacts. Or, adjacent contact carriers can have projections facing one another, e.g., in the form of bulges.If the sensor is designed as a normally closed contact, the projections ensure that the two electrical contacts are securely in contact with each other after the surface element has folded the sensor three-dimensionally due to its restoring forces, e.g., during manufacturing or after activation during use, causing the sensor to deform accordingly. If the sensor is designed as a normally open contact, the projections—located at a different location—bring the two contacts securely into contact when the sensor is deformed during use, thus triggering a switching operation.

[0031] The electrical contacts are connected by electrical conductors to connect the contacts to each other, depending on the sensor's design, if necessary—namely, in the case of an opener—and to enable connection of the sensor to a current or voltage source, or to an evaluation circuit, or the like. Compared to electrical conductors, an electrical contact represents a comparatively large contact area, ensuring reliable coverage of adjacent contacts, given the sensor's mobility and the relative mobility of the contacts.

[0032] In one embodiment, the contacts can be formed by the electrical conductors themselves, namely by extending the electrical conductors in a spiral, zigzag, meander, or similar planar pattern where the contact zone is to be created, while the conductors run in a narrow linear pattern between the contact zones. However, high electrical resistances often occur at deflection points, such as bends where the conductor is bent at 90° or more.

[0033] In one embodiment, it can be provided that the contacts are designed as electrically conductive flat elements.

[0034] Contacts as electrically conductive surface elements can be designed, for example, as strips and / or plates made of highly conductive metals such as aluminum, copper, silver, and / or gold, and / or of highly conductive plastic materials. The electrical conductors serve to connect such flat contact zones to one another.

[0035] In one embodiment, it can be provided that the contacts connect to electrically conductive areas of the surface element.

[0036] When using a multilayer film as a carrier, the electrical conductors and / or the comparatively wider contacts can be formed by correspondingly conductive areas of a film layer. When using a textile fabric, the conductors and / or the contacts can be formed by fibers of the fabric, similar to what is known from patterns of different colors of a textile fabric, and is made possible by the appropriate weaving, knitting, or knitting method, namely by using both electrically conductive and electrically insulating fibers to produce the respective textile fabric.

[0037] In one embodiment, it can be provided that wires are connected to the contacts.

[0038] The wires can be made of different materials, for example metal, carbon fibers, or an electrically conductive plastic. Because the electrical conductors are formed by elements that the sensor has in addition to the surface element, the surface element can be selected independently of its electrical properties. Given the extensibility of the surface element, the separate wires can reliably prevent interruptions in the electrical conductors, which could otherwise occur if electrically conductive areas of the surface element are overstretched. The use of wires as electrical conductors makes it possible, for example, to use wires so thin that they can be sewn together. This supports a material-appropriate design of the sensor, especially when a textile fabric is used as a flexible surface element.

[0039] The wires are connected to the contacts either to connect contacts to each other, for example, in the contact chain of an opener, or to connect the sensor to external elements such as a current or voltage source, an electronic evaluation circuit, a controller, or the like. The wires can connect either to the separate, flat contacts or to the contact zones formed by the flat element itself.

[0040] In one embodiment, it can be provided that the contacts form an opener arrangement and are preferably connected to one another in a meandering manner by electrical conductors.

[0041] The contacts advantageously form an opener arrangement. The deformability of the sensor in the form of a folded structure enables a sensor design in which two electrical contacts located on two different sections of the folded carrier touch each other and are separated from each other when the carrier is deformed. In a design as a sensor in the form of a point button, the sensor only has these two contacts. In a design as an elongated sensor in the form of a switch strip, the sensor has several contacts on each of these two different sections, and the contacts are connected to each other by electrical conductors, preferably in a meandering pattern, so that a continuous electrical line is created that constantly changes from one section of the carrier to the other. This line is interrupted when a single contact pair is separated, thus changing the switching state of the sensor.

[0042] Furthermore, it can be provided that the contacts form a normally open arrangement.

[0043] As an alternative to the design as an opener, the sensor can be designed as a closer, in which two contacts are spaced apart from each other and come into contact with each other when the carrier is deformed.

[0044] Furthermore, it is possible to combine two circuits, namely an NC circuit and a NO circuit, creating a dual-channel, multi-redundant sensor. In combination with a suitable controller, this enables a very high level of safety.

[0045] In one embodiment, it can be provided that the surface element and the contacts are arranged in an elastically deformable casing.

[0046] For example, the carrier and contacts are arranged in an elastically deformable casing. The casing provides mechanical protection, which is particularly advantageous when the sensor is designed to be delicate and lightweight. The elastic deformability of the casing enables the sensor to be deformed and then reset after such deformation when contact with an obstacle is removed.

[0047] Furthermore, the enclosure can be designed to be completely closed and moisture-proof. In one embodiment, the elastic enclosure is completely closed and moisture-proof. The completely closed design prevents the penetration of foreign bodies that could impair the electrical connection between adjacent electrical contacts of the sensor and / or the deformability of the sensor. Furthermore, the penetration of moisture is prevented, which could damage the electrical conductors or contacts through oxidation or cause an undesired electrical short circuit and thus a malfunction of the sensor.

[0048] In a further development, it can be provided that the sheath is elongated like a tube, and preferably the contacts are arranged in such a way that the sensor is designed as a switching strip.

[0049] The casing can be designed approximately in a point-like manner, for example circular, hemispherical or the like, so that the sensor can be used as a button. In one embodiment, the casing is designed in an elongated, tube-like manner, so that the sensor can preferably be used as a switching strip in safety technology, for example as anti-pinch protection or as protection for freely moving objects. The tube-like design of the casing results in a completely closed cross-section of the casing, so that it only needs to be closed at both ends, for example with a pourable sealing compound or with a sealing plug after the elongated sensor has been drawn into the tube. The tube-like design of the casing can be realized using a one-piece hollow profile, so that a seamless cross-section of the casing is achieved and thus optimal moisture protection is provided.In another embodiment, the tubular design is created by a two-part cross-section of the casing, thus simplifying the insertion of the sensor into the casing. The two cross-sectional sections of the casing can then be joined together in a moisture-tight manner by vulcanization or adhesive bonding.

[0050] By cutting the elastic surface element to a correspondingly large size, large-area sensors can be created that can serve as a safety mat. Alternatively, a safety mat can be created by arranging several safety strips in parallel or by arranging a serpentine pattern of a correspondingly long individual safety strip or several safety strips arranged one behind the other. In the case of a safety mat, the casing is designed to be as large as the safety mat itself; this can represent the only casing of the sensor, or the casing the size of a safety mat represents an outer casing layer within which a safety strip provided with its own casing can be arranged. Furthermore, in one embodiment, a safety mat can have a plurality of individual, spaced-apart sensors that are distributed over the surface of the safety mat.Easy handling of this multitude of individual sensors can be achieved by not manufacturing the sensors separately and having to be handled individually, but rather by designing them as local sections of a large elastic surface element with the respective corresponding support structure and the locally arranged contacts.

[0051] In one embodiment, it can be provided that the surface element and the contacts are arranged in a casing which is formed from a foam material.

[0052] Furthermore, it can be provided that the sensor is designed as a so-called bumper or switching buffer.

[0053] The support structure is firmly connected to the surface element, so that the support structure partially hinders the contraction of the previously stretched surface element, thus enabling folding into the desired three-dimensional shape of the sensor. Depending on the design of the elastic surface element, different connection technologies can be used to firmly connect the support structure to the surface element. For example, the elements of the support structure can be glued to the surface element using an elastic adhesive. This means that while the support structure hinders the movement of the elastic surface element, the elastic properties of the adhesive help prevent stress peaks that could lead to undesired detachment of the surface element from the support structure.Alternatively, a slightly elastic adhesive which is as rigid as possible after curing can be used if the aforementioned problem of detachment does not occur, in order to achieve the desired restriction of movement of the - lö.

[0054] surface element, which is to be achieved by means of the support structure, as unrestricted as possible.

[0055] As an alternative to gluing, the support structure can be welded to the surface element, for example by applying heat or by ultrasonic welding. In this case, heating of the surface element should be limited as precisely as possible to the area in which it comes into contact with the support structure, because contact with the support structure no longer allows the elastic extensibility of the surface element. Outside of this contact area, however, exposure to heat can cause the surface element to lose its elastic properties completely or to a considerable extent. This means that repeated deformation of the sensor during use can result in damage to the surface element in these less elastic areas not stabilized by the support structure, e.g. in the form of cracks or breaks.

[0056] As a result, it is advantageous, regardless of the joining technology used, to leave the surface element elastically deformable and stretchable outside the contact surface adjacent to the support structure.

[0057] The support structure can be made of prefabricated elements to minimize the time required for sensor production. For example, the support structure can be manufactured using injection molding, especially if the sensor is to be produced in large quantities.

[0058] In one embodiment, the support structure lies not only on one of the two sides of the surface element, but on both sides. If, for example, a hinge line is created on one side by the support structure having interruptions along a continuous imaginary line, a support structure can be arranged on the opposite side of the surface element that extends beyond this hinge line. In this way, folding of the surface element is only possible in a certain predetermined folding direction and the hinge is blocked in the other, undesired folding direction, so that in the sense of the aforementioned "seif assembly" principle, the desired three-dimensional shape is automatically assumed without additional, external forces having to initiate or completely carry out certain folding processes.If support structures are to be arranged on both sides of the surface element, they can be mechanically connected to one another, for example, by clipping, so that a direct connection of a support structure to the surface element is not necessary. For example, on one side of the surface element, the support structure can have arrowhead-like projections, and the opposite support structure can have openings that interact with them. In this case, the surface element would be pierced at specific points. This is straightforward with a textile material, for example, and does not lead to tearing of the surface element if the projections extend through the pores of the textile without damaging the fibers.Alternatively, one support structure may have a groove, for example with a dovetail-shaped cross-section, and the opposite support structure may have a cooperating rib, so that the surface element running between the two support structures is clamped but not penetrated.

[0059] In one embodiment, it can be provided that the support structure is printed as a 3D print onto the surface element.

[0060] A support structure 3D printed onto the surface element is therefore only created at the moment of contact with the surface element. Initial, non-public tests have shown that the support structure can be formed from comparatively flat lines, so that 3D printing can be carried out with little time expenditure. Scalability of the support structure, either by duplicating and arranging individual sections, or by enlarging it to scale, can be achieved with little effort using 3D printing, so that the support structure can be easily adapted to the desired dimensions of the sensor to be created. Furthermore, the trigger pressure, which is determined by the design of the support structure, can be adapted just as easily to the desired properties of the sensor thanks to the variability of 3D printing.

[0061] Depending on the design of the 3D printer, different materials can be used for the support structure, such as metals, but also plastic materials such as PLA or ABS. In initial tests, PETG has proven to be a suitable plastic material for the support structure. This is because, on the one hand, the desired rigidity of the support structure can be achieved to ensure the folding process and the subsequent maintenance of the desired shape of the sensor. On the other hand, compared to more rigid materials, the support structure can exhibit sufficient flexibility to prevent unwanted detachment of the surface element from the support structure. The surface element is stretched and held in this stretched state, for example, by clamping it onto a surface.The degree of elongation depends on the design of the elastic surface element and the resulting restoring forces and can, for example, range from 30% to 80%. A strong connection to the support structure can be achieved by form-fitting and / or material-bonding.

[0062] Printing the stretched surface element with molten plastic material means that the plastic material, due to its flow properties, can penetrate into the structure of a textile surface element or, due to its heat, can fuse with a film forming the surface element, for example a laminate layer of the multilayer film, wherein this laminate layer has a sufficiently low melting point to form an intimate bond with the material of the support structure. Even when using a textile fabric for the surface element, a material-to-material bond can be achieved in addition to the positive penetration of the molten plastic into the textile structure if the textile fabric has fibers or fiber components that have a suitable melting point.

[0063] In a further development, it can be provided that the relaxed, folded surface element has an elongated rib with a substantially V-shaped cross-section forming two inclined surfaces.

[0064] In one embodiment of the sensor, the surface element and the support structure are coordinated with one another in such a way that the surface element, after it has been relaxed and has deformed three-dimensionally due to the support structure, forms an elongated rib, preferably with a substantially V-shaped cross-section having two inclined surfaces. A sensor having such a rib can be deformed in a simple manner by exerting pressure on the tip of the V so that the two inclined surfaces are spread apart. Alternatively, the surface element and the support structure can be coordinated with one another in such a way that, in the relaxed, folded state, they form an elongated component with an approximately circular, oval, or rectangular cross-section. This elongated basic shape can be straight or curved, which can also be determined by the design of the support structure and / or the type of expansion of the surface element.An elongated basic shape is well suited for using the sensor in safety technology as a switching edge or as a component of a switching edge, e.g. with an outer casing.

[0065] Instead of forming an elongated basic shape, the surface element and the support structure can be coordinated in such a way that in the relaxed, folded state they assume an approximately round, petal-like shape and have several projections that can be deformed under pressure, for example, in a similar way to that described above for the elongated rib.

[0066] Due to the possibility of designing the support structure in a filigree manner, the sensor according to the invention can also be deformable as a whole, so that it can, for example, run around radii and, with a correspondingly adapted design of the support structure, can also run around corners, for example around 90° corners.

[0067] Advantageously, it can be provided that the sensor is designed as a normally closed contact and has two adjacent ribs, between the tips of which the contacts are arranged adjacent to one another at a distance, such that the pressure on a rib spreads its inclined surfaces and a contact of this rib comes into contact with a contact of the adjacent rib.

[0068] In one embodiment, such a sensor forms a normally closed contact by having two adjacent ribs. Upon contact with an obstacle, both ribs are deformed accordingly, and the spreading of the inclined surfaces causes the two adjacent, mutually facing inclined surfaces, which were previously spaced apart, to come into contact with each other. Electrical contacts arranged on these two mutually facing inclined surfaces can touch each other as a result of this movement, so that the sensor changes its switching state from "open" to "closed." Furthermore, it can be provided that the sensor is designed as a normally closed contact and contacts are arranged on the inner sides of the two inclined surfaces in such a way that two opposing contacts are generally in contact, and that the pressure on the rib spreads its inclined surfaces and the two contacts are spaced apart from each other.

[0069] Alternatively, such a sensor with a rib forms a normally closed contact. For this purpose, the two inclined surfaces have an electrical contact on their inner side, which faces the opposite inclined surface. The two contacts are generally in contact, i.e., when no external forces act on the sensor. However, if pressure on the rib spreads the inclined surfaces, the contacts move apart, causing the sensor to change its switching state from "closed" to "open."

[0070] A second aspect of the invention relates to the use of an elastic surface element, in particular a 4D textile, as a carrier for the contacts of a tactile sensor.

[0071] The basic technology of 4D textiles is known. One aspect of the present invention involves using a 4D textile as a carrier for the contacts of a tactile sensor.

[0072] Sustainable production of the sensor can be achieved by using only natural materials for the surface element, such as cotton, which also allows for the desired stretchability in the form of a cotton jersey. The support structure can also be made of biodegradable material to promote sustainable sensor production, for example, in a 3D-printed support structure using a biodegradable filament.

[0073] In order to allow the elastic restoring forces to act in a targeted manner and to achieve a predetermined folding of the 4D textile so that the sensor automatically assumes its desired three-dimensional shape when the surface element is relaxed in the manner of a “seif assembly” process, the following measures can be applied in addition to what has already been described: • Two or more separate surface elements can be used.

[0074] For example, two different types of surface elements can be used. The two types can be made of different materials, for example, by differing in their recovery forces. However, the two types can also be designed identically and differ only in that they are stretched in different directions before being connected to the support structure, so that when the surface elements are relaxed, they fold in different directions.

[0075] For example, a first type of surface element can span the entire area that is to be provided with the support structure, while a second type of surface element may only be arranged in strips where hinge lines are structurally provided in order to cause the support structure to fold in a specific direction there.

[0076] • The surface element can be stretched in two or more steps.

[0077] After an initial stretch, the surface element is connected to a first part of the support structure. The surface element is then stretched in a second step, either more strongly in the same direction as in the first stretching step, or it is stretched in a different direction than in the first step, and then connected to a second part of the support structure. Alternatively, the surface element is connected to a first part of the support structure after an initial stretching and then relaxed, with this relaxation being partially hindered by this first part of the support structure. The surface element is then stretched in a second step, in the same or a different direction than in the first stretching step, connected to a second part of the support structure, and then relaxed.

[0078] Variations are possible in that the mentioned stretching can occur in each of the stretching steps either in a single direction or in two or more directions.

[0079] • As already mentioned above, the support structure can be arranged on both sides of the surface element.

[0080] For example, a first layer of the support structure can be created by 3D printing, then the surface element can be placed on this layer of the support structure, and finally a second layer of the support structure can be created by 3D printing on the surface element.

[0081] Or a prepared first part of the support structure can be applied to the surface element on a first side of the surface element or already connected to the surface element, and then a prepared second part of the support structure can be applied to the surface element on the opposite second side of the surface element and connected to the first part of the support structure or to the surface element.

[0082] Two or more separate surface elements can also be used for other reasons: one of the surface elements can form a protective layer on the finished sensor, either on an inner side of the sensor, where, for example, the electrical contacts can be located, so that they are mechanically protected if the sensor is pressed completely flat, or on the outside of the sensor, so that it can be protected from external influences such as moisture or dirt and an additional outer covering may not be necessary.

[0083] The measures mentioned may be based on an independent inventive value.

[0084] In one embodiment, it can be provided that the cross section of the rib has a tip and two base points, wherein the sensor rests against a contact surface with the base points, and that at at least one base point the rib has at least one sliding cushion which, in use, slides along the contact surface when the sensor is deformed.

[0085] As already mentioned, the sensor can be designed so that it can be flattened upon contact with an obstacle, whereby it is pressed against a contact surface. In one embodiment, the sensor has sliding pads that are in contact with the contact surface either constantly or at least when the sensor is deformed, so that they slide along the contact surface when the sensor is deformed. Friction of the surface element on the contact surface is thus reduced or even completely avoided, so that the surface element does not wear out prematurely and the service life of the sensor is as long as possible. The sliding pads can either be part of the support structure or consist of the same or a different, particularly low-friction material. Advantageously, they can be attached to the surface element together with the support structure in the same production step in order to keep the effort required for manufacturing the sensor as low as possible.

[0086] The invention is explained in more detail below using purely schematic representations.

[0087] Fig. 1 A plan view of an arrangement consisting of a stretched flexible surface element, a support structure, electrical conductors and electrical contacts,

[0088] Fig. 2 is a perspective view of the arrangement of Fig. 1 after the relaxation of the surface element,

[0089] Fig. 3 is a perspective view of the arrangement of Fig. 2 folded into a sensor, the sensor being shown in its rest position,

[0090] Fig. 4 is a view similar to Fig. 3, showing the sensor in its trigger position,

[0091] Fig. 5 shows a cross-section through a switching strip, with the individual elements shown at a distance from each other,

[0092] Fig. 6 and 7 a second and a third embodiment of a switching strip,

[0093] Fig. 8 and 9 show two embodiments in which the sensor is arranged in a bumper,

[0094] Fig. 10 a fourth embodiment of a switching strip,

[0095] Fig. 11 is a view of a section of a fifth embodiment, from the side of the support structure,

[0096] Fig. 12 is a view of the embodiment of Fig. 11, seen from the opposite side,

[0097] Fig. 13 is a view of a section of a sixth embodiment, from the side of the support structure, and

[0098] Fig. 14 is a view of the embodiment of Fig. 13, seen from the opposite side.

[0099] Fig. 1 shows a plan view of a stretched surface element 1, which is clamped onto a plate that can be used, for example, as a printing platform for a 3D printer. In the illustrated embodiment, the surface element 1 is formed from a textile fabric in the form of a single jersey. In this stretched state, a support structure 2 is printed onto the surface element, namely from a PLA plastic filament using a 3D printing process. The support structure 2 consists of a plurality of approximately semicircular arches 3, wherein the individual arches 3 are always separated from one another by small distances. The separation points 4 created in this way create hinge lines along which the surface element 1 folds automatically when it is removed from the plate and contracts in an effort to regain its original dimensions.

[0100] Electrical conductors s have been applied to the surface element 1, which in the illustrated embodiment are designed as wires, namely as enameled wire. Furthermore, the surface element 1 carries electrical contacts 6, which in the illustrated embodiment are designed as flat sections of a metallic foil, namely a copper foil, and which are electrically conductively connected to the electrical conductors 5.

[0101] In the illustrated embodiment of the support structure 2, two inner rows of arches 3 are arranged opposite one another in such a way that together they almost form a series of circles. At the two ends of this row, the arches 3 are not shaped into a semicircle, but rather angled to form stabilizing end webs 7 of the support structure 2. Purely by way of example, the surface element 2 extends outward beyond these end webs 7, although this respective projection of the surface element 2 can also be omitted, deviating from the illustrated embodiment.

[0102] Furthermore, the support structure 2 has two outer rows of arches 3 which are separated from one another by the middle arches 3 and which, in contrast to the middle arches 3, are each provided with an intermediate web 8 which stabilizes the support structure 2 at the outer edges of the surface element 1. This stabilization counteracts the tendency for the sensor to bend in its longitudinal direction after the surface element 1 has been released. Furthermore, the intermediate webs 8 are used to attach the electrical contacts 6 by, for example, providing a closed surface, unlike the textile structure of the surface element 2, and thus the largest possible surface for bonding. Fig. 2 shows the surface element 1 of Fig. 1 after it has been removed from the plate onto which it was clamped.Due to the elastic restoring forces, the surface element 1 automatically deforms in an effort to return to its original dimensions. The restoring forces are indicated by four arrows pointing from the outside toward the center of the surface element 1. The recovery of the elastic surface element 1 is hindered by the comparatively stiffer support structure 2, so that the separation points 4, each arranged in a row, act like a hinge line around which the surface element 1 automatically folds.

[0103] The two rows of central arches 3 form a rib with a substantially V-shaped cross-section and two inclined surfaces 9. Purely by way of example and for the sake of clarity, Fig. 2 shows the two outer rows of arches 3 folded outward. Furthermore, for reasons of clarity, the electrical conductors 5 and contacts 6 are not shown in Fig. 2.

[0104] Fig. 3 illustrates, in a representation just as schematic as Fig. 2, i.e. without electrical conductors 5 and contacts 6, that the two outer rows of sheets 3 are folded inwards, so that an operational sensor 10 is now created. The sensor 10 forms a rib with a triangular cross-section and has two inner surfaces 11 and 12 within the two outer inclined surfaces 9, in each of which the outer sheets 3 of Fig. 1 are arranged. As can be seen from Fig. 1, these two outer rows of sheets 3 carry the electrical contacts 6 on the intermediate webs 8, so that the contacts 6 of the two inner surfaces 11 and 12 touch one another. Below the perspective view, Fig. 3 shows a highly simplified cross-sectional view of how the contacts 6 of the short inner surface 11 rest against the contacts 6 of the long inner surface 12.

[0105] Deviating from the illustrated embodiment, the two inner surfaces 11 and 12 can be designed to be of equal length. The last inner surface 11 or 12 folded inward is impeded in its movement by the other inner surface 11 or 12 that was previously folded inward, so that the contacts 6 abut one another when the sensor 10 is configured as an opener.

[0106] The course of the electrical conductors 5 shown in Fig. 1 creates a continuous electrical line over the length of the sensor 10, with individual line sections alternating, which run either on the short inner surface 11 or on the long inner surface 12 and each connect to the adjacent line section of the other inner surface 12 or 11 in the area of ​​two touching contacts 6. The sensor 10 is thus designed as a normally closed contact, through which a quiescent current flows during use and which generates a switching signal when the quiescent current is interrupted, namely by interrupting the aforementioned electrical line. Fig. 3 shows the sensor 10 in its rest position, in which the contacts 6 touch one another and the electrical line is continuous.

[0107] Figures 2 and 3 are idealized representations. Due to its restoring forces, the elastic surface element 1 causes, for example, the upper edge of the sensor 10, along the tip of the rib, not to run in a straight line as shown in the drawings, but rather to run concavely between adjacent arches 3 of the support structure 2.

[0108] Fig. 4 shows the sensor 10 in a representation similar to Fig. 3, wherein pressure is exerted on the tip of the triangular rib, as indicated by the arrow in Fig. 4. Under this pressure, the sensor 10 has deformed, with the two inclined surfaces 9 being spread against the restoring forces of the elastic surface element 2 around the hinge line created by the separation points 4 of the central arches 3. Since the two inner surfaces 11 and 12 adjoin the two remote lower ends of the inclined surfaces 9, the two inner surfaces 11 and 12 are also moved apart by this spreading movement. The separation surfaces 4 between the central and outer arches 3 also act as hinge lines and enable mobility of the inner surfaces 11 and 12 relative to the adjacent inclined surface 9.

[0109] By moving the two inner surfaces 11 and 12 apart, a distance is also created between the previously adjacent contacts 6, so that the electrical line and thus the quiescent current flowing through the line is now interrupted. This can be seen in the schematically indicated cross-sectional sketch in Fig. 4. The sensor 10 has thus changed its switching state compared to Fig. 3 in that the contacts 6 have been opened, so that Fig. 4 shows the trigger position of the sensor 10, in contrast to the rest position in Fig. 3. Fig. 5 shows a cross-section through a switch strip 14 in which the switching element is created by a sensor 10 according to Figs. 1 to 4. For the sake of clarity, the individual components are not shown directly adjacent to one another, but at a short distance from one another. According to Fig. 5, the sensor 10 is in its rest position, which can also be seen in Fig. 3.The sensor 10 is arranged in a casing 15, which is configured like a tube, namely as an elongated hollow profile with a closed cross-section. The casing 15 is made of an elastomer material and is therefore deformable, so that upon contact with an obstacle, pressure can be exerted on the tip of the sensor 10, triggering the switching process of the sensor 10.

[0110] The casing 15 can be attached directly to a component that is to be provided with the switching strip 14. In the illustrated embodiment, the casing 15 is adhesively bonded to an adapter profile 16, wherein the adapter profile 16 essentially consists of three sections: an adhesive surface 17 serves for connection to the casing 15, a holding surface 18 serves to connect the adapter profile 16 to a suitable holder, and a central section of the adapter profile 16 serves as a spacer 19 to space the adhesive surface 17 and the holding surface 18 from each other.

[0111] The holding surface 18 is accommodated in a C-shaped metal profile 20, and depending on the wall thickness of the metal profile 20, the spacer 19 ensures that the adapter profile 16 can be easily inserted into the metal profile 20. The casing 15 can be inexpensively manufactured as an elastomer profile in a long length and can be cut to the desired length of a switch strip 14. In conjunction with the sensor 10 arranged therein, it ensures consistent and standardized properties of the various switch strips 14.

[0112] By using different adapter profiles 16, the safety strips 14, if they are not mounted directly on a component to be protected, can be adapted to different mountings, e.g., to different metal profiles or to grooves arranged in objects to be secured for attaching a safety strip 14. Furthermore, the adapter profiles 16 can be made of a material that allows for low-resistance insertion into the metal profile 20.

[0113] Because the safety strip 14 is not mounted directly on a component to be protected, for example, it is glued to this component, the safety strip 14 can be replaced quickly and inexpensively in the event of damage by removing it from the holder such as the metal profile 20 shown with the adapter profile 16 and replacing it with an undamaged safety strip 14.

[0114] Deviating from the illustrated embodiment, the casing 15, the adapter profile 16, the retaining surface 18, and the spacer 19 can be made in one piece and from the same material or—e.g., by co-extrusion—from different materials, e.g., from plastics with different Shore hardnesses. Such a one-piece profile facilitates production because different elements do not have to be joined together to form the profile. With the retaining surface 18, such a co-extruded profile can be inserted into a receiving groove like the metal profile shown in Fig. 5.

[0115] The metal profile 20 or a comparable receiving groove enables the casing 15, together with the sensor 10 and the adapter profile 16, to be replaced quickly, which can be advantageous in a harsh operating environment where damage to the switch strip 14 is likely to occur frequently. Deviating from the illustrated embodiment, the metal profile 20 and the adapter profile 16 can be omitted if a permanent attachment of a sensor 10 and the smallest possible dimensions are desired.

[0116] Fig. 6 shows that instead of a receiving groove—as is realized, for example, in the metal profile 20 of Fig. 5—a laterally projecting tab 21 can be used to attach the switch strip 14 to a movable element 22. Together with a base 23, the tab 21 consists of a harder material, which is coextruded together with the comparatively softer casing 15.

[0117] Furthermore, Fig. 6 shows that the sensor 10 is arranged at the rear of the casing 15, i.e. closer to the movable element 22 than to the free end of the casing 15 remote from the movable element 22. To ensure the most sensitive, early response possible of the switching strip 14 upon contact with an obstacle, a plunger 24 extends from the front, free end of the casing 15 backwards to the sensor 10. To ensure that the plunger 24 does not evade the sensor 10, the plunger 24 is guided on both sides by a cross member 25. Together with the casing 15, the cross member 25 defines a sensor chamber 26 within the switching strip 14, in which the sensor 10 is arranged.

[0118] Fig. 7 shows a cross section through a switching strip 14, wherein the attachment is effected by means of a holding surface 18 as in the embodiment of Fig. 5. The sensor chamber 26 and the sensor 10 arranged therein are located at the front, free end within the casing 15. Upon contact with an obstacle, a rapid response of the sensor 10 is thus ensured, and the length of the casing to the rear up to the holding surface 18 determines the overtravel path available for braking a movable element until this element itself comes into contact with the obstacle.

[0119] Fig. 8 shows an arrangement in which a sensor 10 is arranged on a movable element 22 not in a switching strip, but in a bumper 27. The sensor chamber containing the sensor 10 is located in a front section 28 of the bumper 27, made of a foam material. A rear section 29 of the bumper 27 is attached, e.g., glued, to the movable element 22 and determines the aforementioned overtravel path through its length. The rear section 29 can be made of the same foam material as the front section 28 or a different material, e.g., a foam material with a different density.

[0120] Fig. 9 shows an arrangement in which a sensor 10 is arranged in a one-piece bumper 27 on a movable element 22, specifically at the rear, with the sensor chamber 26 being delimited to the rear by the movable element 22 itself. Depending on the strength of the deformable material—usually a foam material—from which the bumper 27 is made, a sensitive response behavior of the sensor 10 can also be achieved in this case by the sensor 10 changing its switching state as soon as possible after contact of the bumper 27 with an obstacle.

[0121] Fig. 10 schematically shows an arrangement in which a sensor 10 is arranged in a switch strip 14 on a movable element 22. The design of the sensor 10 basically corresponds to the design explained with reference to Figs. 1 to 5. In contrast to Fig. 5, the dimensions of the inclined surfaces 9 and the inner surfaces 11 and 12, and also the dimensions of the casing 15 adapted thereto, are selected such that the switch strip 14 has a great installation depth, similar to a bumper 27 shown in Fig. 9. Accordingly, the material—e.g., the aforementioned foam material—of a bumper 27 can be saved, which enables a particularly lightweight design of the entire arrangement. The specific design of the inner surfaces 11 and 12 as well as the electrical contacts 6 of the sensor 10 determines after which deformation path of the switch strip 14 the contacts 6 open and the sensor 10 thus changes its switching state.In this way, a sensor arrangement with a lower weight can be created compared to a similarly sized bumper, which, due to its larger dimensions, allows for an overtravel path just as long as when using a bumper compared to the usual, smaller switching edges.

[0122] Fig. 11 shows a detail of a further embodiment of a sensor 10, seen from the side of the support structure 2. In this embodiment too, the surface element 1 is designed in the form of a textile and the support structure 2 is produced in the form of a 3D print on the surface element 1. In this embodiment too, the support structure 2 forms a plurality of arches 3. The section of the sensor 10 shown in Fig. 11 contains two ribs that run parallel to one another and in which adjacent arches 3 end, wherein the ends of adjacent arches 3 are connected to one another and each form a contact carrier 30. Each contact carrier 30 has an approximately triangular cross-section and thus forms a projection that projects from the plane in which the two associated arches 30 run in the direction of an adjacent contact carrier 30.The contact carriers 30 form comparatively large-area sections within the support structure 2 and can be covered with flat contact elements, for example with molded parts made of an electrically conductive material, or with film sections or small plates made of such a material, or the like.

[0123] In use, the contact carriers 30 are located at the tip of the respective rib. In the section of the sensor 10 shown in Fig. 11, two ribs are located within the image section, and to create a large-area sensor 10, for example in the form of a switching mat, a plurality of ribs can be arranged next to one another. This can be achieved by selecting a correspondingly large-area surface element 1 or by connecting several surface elements 1 to one another. In the illustrated embodiment, in which the surface element 1 is designed as a textile, adjacent surface elements 1 can, for example, be sewn together to create a correspondingly large-area sensor 10.

[0124] In the exemplary embodiment shown in Fig. 11, the tips of the two ribs are located where the arches 3 end and are connected to one another by the contact carriers 30. Opposite them, at the apex of the arches 3, are the base points of the ribs. In the exemplary embodiment shown, adjacent ribs do not directly adjoin one another; rather, a narrow gap is provided between them, in which sliding pads 31 are arranged. The sliding pads 31 are not connected to the support structure 2, but like the support structure 2, they were produced by 3D printing the surface element 1 and connected to the surface element 1—in the same operation.

[0125] Deviating from the illustrated embodiment, the sliding pads 31 can also be configured as sections of the support structure 2. When pressure is exerted on the tip of a rib due to contact of the sensor 10 with an obstacle, the rib slides with at least one of its two base points on a contact surface against which the base points of the rib rest. Wear on the sensor 10 is minimized by the fact that this sliding movement, and thus the friction, occurs on the sliding pads 31 provided specifically for this purpose.

[0126] Fig. 12 shows the embodiment of Fig. 11, also in detail, from the opposite side of the surface element 1, so that the support structure 2 is visible but concealed by the surface element 1. The two ribs of the sensor 10 running parallel to each other are visible, with the pairs of contact types 30 in the respective tips of the ribs on the one hand and the guide cushions 31 between the base points of adjacent ribs on the other hand being visible.

[0127] Fig. 13 shows a section of another embodiment of a sensor 10, again similar to Fig. 11, viewed from the side of the support structure 2. The sensor 10 is constructed similarly to the embodiment of Fig. 11, but has two different types of contact carriers 30: wide contact carriers 30 with an approximately triangular cross-section are - unlike in the embodiment of Fig. 11 - not arranged at the ends of the arches 3, but intermediate webs 8 extend further than in the embodiment of Fig. 2 from the apex of the arches 3 to the tip of the respective rib, where they form the wide contact carriers 30.

[0128] At the ends of the arches 3 there are also contact carriers 30, which are, however, considerably narrower than the wide contact carriers 30 on the intermediate webs 8. While the wide contact carriers 30 have a triangular cross-section and thus, in use, a curvature which faces the respective adjacent contact carrier 30, the narrow contact carriers 30 at the ends of the arches 3 are not arranged flush with one another and opposite one another, but rather are arranged offset from one another in the manner of a toothing.

[0129] The embodiment of Fig. 13 differs from that of Fig. 11 in that the intermediate webs 8 support an arrangement of all ribs that is as flat as possible and thus the design of a flat sensor 10, whereas in the embodiment of Fig. 11 the ribs are curved due to the restoring forces of the surface element 1, for example, to form a sensor 10 that rests as precisely as possible against a curved, movable component. Furthermore, the narrow contact carriers 30 in the embodiment of Fig. 13 ensure high trigger sensitivity of the sensor 10, since the number of contact points along the length of a rib is increased compared to the embodiment of Fig. 11.

[0130] Fig. 14 shows the sensor 10 of Fig. 13 from the opposite side, i.e., looking toward the surface element 1, with the support structure 2 visible through the surface element 1. The arches 3, the intermediate webs 8, the wide and narrow contact carriers 30, and the sliding pads 31 are visible. Reference numerals:

[0131] 1 surface element

[0132] 2 Support structure

[0133] 3 sheets

[0134] 4 Separation point

[0135] 5 Electrical conductor

[0136] 6 Electrical contact

[0137] 7 End bridge

[0138] 8 intermediate bridge

[0139] 9 inclined surfaces

[0140] 10 Sensor

[0141] 11 Short inner surface

[0142] 12 Long inner surface

[0143] 14 Switch strip

[0144] 15 Wrapping

[0145] 16 adapter profile

[0146] 17 Adhesive surface

[0147] 18 holding surface

[0148] 19 spacers

[0149] 20 metal profile

[0150] 21 tab

[0151] 22 Movable element

[0152] 23 bases

[0153] 24 tappets

[0154] 25 T raverse

[0155] 26 Sensor chamber

[0156] 27 bumpers

[0157] 28 Front section

[0158] 29 Rear section

[0159] 30 contact carriers

[0160] 31 sliding cushions

Claims

Claims:

1. Tactile sensor (10), • with electrical contacts (6), • and with a carrier, o which holds the contacts (6) in a predetermined arrangement, o and which is elastically deformable in such a way that the contacts (6) are movable relative to one another between a first, touching position and a second, separated position, characterized in that the carrier has a tensioned, pre-stretched elastic surface element (1) which is firmly connected to a support structure (2) and, after relaxation, is automatically brought into a three-dimensional shape determined by the support structure (2).

2. Sensor according to claim 1, characterized in that the surface element (1) is designed as a textile material.

3. Sensor according to claim 2, characterized in that the surface element (1) is designed as jersey, in particular as single jersey.

4. Sensor according to one of the preceding claims, characterized in that the contacts (6) are sewn to the surface element (1).

5. Sensor according to one of claims 1 to 3, characterized in that the contacts (6) are attached to the support structure (2).

6. Sensor according to one of the preceding claims, characterized in that the contacts (6) are designed as electrically conductive flat elements.

7. Sensor according to one of the preceding claims, characterized in that wires are connected to the contacts (6).

8. Sensor according to one of the preceding claims, characterized in that the contacts (6) connect to electrically conductive areas of the surface element (1).

9. Sensor according to one of the preceding claims, characterized in that the contacts (6) form an opener arrangement and are connected to one another in a meandering manner by electrical conductors (5).

10. Sensor according to one of claims 1 to 8, characterized in that the contacts (6) form a normally open arrangement.

11. Sensor according to one of the preceding claims, characterized in that the surface element (1) and the contacts (6) are arranged in an elastically deformable casing (15).

12. Sensor according to claim 11, characterized in that the casing (15) is closed all around and designed to be moisture-proof.

13. Sensor according to claim 11 or 12, characterized in that the sheath (15) is elongated in the manner of a tube, and the contacts (6) are arranged in such a way that the sensor (10) is designed as a switching strip (14).

14. Sensor according to one of claims 11 to 13, characterized in that the surface element (1) and the contacts (6) are arranged in a casing (15) which is formed from a foam material.

15. Sensor according to one of claims 11 to 14, characterized in that the sensor (10) is designed as a so-called bumper or switching buffer.

16. Sensor according to one of the preceding claims, characterized in that the support structure (2) is printed as a 3D print on the surface element (1).

17. Sensor according to one of the preceding claims, characterized in that the relaxed, folded surface element (1) has an elongated rib with a substantially V-shaped cross-section forming two inclined surfaces (9).

18. Sensor according to claim 17, characterized in that the cross section of the rib has a tip and two base points, the sensor (10) resting with the base points of a contact surface, and in that at least one base point the rib has at least one sliding pad (31) which, in use, slides along the contact surface when the sensor (10) is deformed.

19. Sensor according to claim 17 or 18, characterized in that the sensor (10) is designed as a normally open contact and has two adjacent ribs, between the tips of which the contacts (6) are arranged adjacent to one another at a distance, such that the pressure on a rib spreads its inclined surfaces (9) and a contact (6) of this rib comes into contact with a contact (6) of the adjacent rib.

20. Sensor according to claim 17 or 18, characterized in that the sensor (10) is designed as an opener and contacts (6) are arranged on the inner sides of the two inclined surfaces (9) in such a way that two opposite contacts (6) basically touch each other, and that the pressure on the rib spreads the inclined surfaces (9) thereof and the two contacts (6) are spaced apart from each other.

21. Use of an elastic surface element (1), in particular a 4D textile, as a carrier for the contacts (6) of a tactile sensor (10).

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