WO2009048910A2 - Sensor assembly comprising a capacitive proximity sensor - Google Patents
Sensor assembly comprising a capacitive proximity sensor Download PDFInfo
- Publication number
- WO2009048910A2 WO2009048910A2 PCT/US2008/079142 US2008079142W WO2009048910A2 WO 2009048910 A2 WO2009048910 A2 WO 2009048910A2 US 2008079142 W US2008079142 W US 2008079142W WO 2009048910 A2 WO2009048910 A2 WO 2009048910A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sensor
- bumper
- conductor
- internal surface
- substrate
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
- G01D5/24—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance
- G01D5/2405—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying capacitance by varying dielectric
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D11/00—Component parts of measuring arrangements not specially adapted for a specific variable
- G01D11/24—Housings ; Casings for instruments
- G01D11/26—Windows; Cover glasses; Sealings therefor
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
- H03K17/945—Proximity switches
- H03K17/955—Proximity switches using a capacitive detector
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R19/00—Wheel guards; Radiator guards, e.g. grilles; Obstruction removers; Fittings damping bouncing force in collisions
- B60R19/02—Bumpers, i.e. impact receiving or absorbing members for protecting vehicles or fending off blows from other vehicles or objects
- B60R19/48—Bumpers, i.e. impact receiving or absorbing members for protecting vehicles or fending off blows from other vehicles or objects combined with, or convertible into, other devices or objects, e.g. bumpers combined with road brushes, bumpers convertible into beds
- B60R19/483—Bumpers, i.e. impact receiving or absorbing members for protecting vehicles or fending off blows from other vehicles or objects combined with, or convertible into, other devices or objects, e.g. bumpers combined with road brushes, bumpers convertible into beds with obstacle sensors of electric or electronic type
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
- H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
- H03K2217/96—Touch switches
- H03K2217/9607—Capacitive touch switches
- H03K2217/960755—Constructional details of capacitive touch and proximity switches
Definitions
- the present invention relates to the mounting of a capacitive proximity sensor in a body to detect the presence of external objects.
- the invention relates more especially (but not exclusively) to the mounting of a capacitive proximity sensor in a vehicle, especially a vehicle bumper.
- Proximity sensors have been used in various industrial applications for locating the presence of materials and for avoiding collisions with articles.
- proximity sensors have been fitted to the rear side and/or bumpers of vehicles so that, when a vehicle is reversed, a warning signal is provided if it approaches an object so that a collision can be safely avoided while still allowing the driver to position the vehicle conveniently close to the object.
- WO 01/08925 (AB Automotive Electronics Ltd.) describes a capacitive proximity sensor for a vehicle, which consists of two strips of metal, or other conductive material, insulated from each other and provided on the inside of the bumper of a vehicle.
- Both plates are connected to a control unit.
- the control unit monitors the change that occurs in the capacitance between the sensor plate and (electrical) ground as the vehicle approaches an external object and provides an indication to the driver of the distance between the sensor plate (and, hence, the vehicle) and the object.
- GB-A-2 400 666 (also of AB Automotive Electronics Ltd.) mentions the manufacture of a capacitive proximity sensor of the type described in WO 01/08925 by screen-printing the sensor and guard plates with conductive ink onto opposite sides of a plastic film substrate, or by forming the sensor and guard plates from aluminium foil that is laminated to the plastic film substrate.
- GB-A-2 400 666 further describes the use of a retention system for retaining the sensor in a vehicle bumper without the need for glues.
- the present invention is concerned with capacitive proximity sensors of the type in which a sensor conductor and a guard conductor are arranged on opposite faces of a dielectric film substrate.
- Sensors of that type offer the advantage that they can be manufactured in a cost-effective manner in the form of a flat sheet that is comparatively easy to store and to handle. They can be applied comparatively easily to flat supporting surfaces and, because they are flexible, to certain non-planar surfaces also (most typically, these will be surfaces that have only one axis of curvature but they could be surfaces that also have limited curvature about a second axis).
- One way of reducing the number of folds and creases that form in the sensor substrate when it is being applied to a shaped supporting surface is to make tapered cuts at appropriate points in the substrate to make it easier to adapt the substrate to the shape of the supporting surface. This increases the complexity of the attachment process, since the shape and location of the cuts must be carefully selected having regard to the shape of the supporting surface to achieve the desired result and to avoid introducing too many points of weakness into the sensor substrate.
- the present invention is concerned with enabling such problems to be avoided while providing a system for attaching a capacitive proximity sensor to a supporting surface that is sufficiently robust to withstand the forces and environmental conditions to which it may be subjected when in use.
- the attachment system should be able to withstand the forces caused by normal use of the vehicle as well as environmental conditions which might include variations in temperature, and exposure to dirt and/or water and/or oil.
- the present invention concerns a sensor assembly comprising a capacitive proximity sensor mounted to a surface of a body to sense the presence of external objects.
- the sensor comprises a dielectric film substrate having front and rear major surfaces that, in use, face respectively outwards and inwards of the body, a sensor conductor on the front major surface, and a guard conductor on the rear major surface to provide an electrical shield for the sensor conductor.
- the invention further concerns the situation in which the surface of the body to which the sensor is mounted does not provide a substantially flat area for direct attachment thereto of the sensor, at least in the sensor conductor region.
- the senor is provided with a mounting to the surface that inhibits the ingress and retention of water/dirt between the sensor and the said surface (at least during normal use) and maintains the sensor in a substantially flat condition, at least in the sensor conductor region.
- the term “substantially flat” includes the case in which the surface is non-planar but only to an extent that still permits the sensor to be attached the surface without being folded and/or creased at least in the sensor conductor region.
- substantially flat may include surfaces that have a single axis of curvature and may even include some surfaces that also have limited curvature about a second axis.
- the term “substantially flat” includes the case in which the sensor is non-planar but only to the extent that it is not folded and/or creased at least in the sensor conductor region.
- the senor is mounted to a supporting surface that does not allow direct attachment without the formation of folds and/or creases in the sensor at least in the sensor conductor region. Nevertheless, the sensor is maintained in a substantially flat condition, at least in the sensor conductor region, and the ingress and retention of water/dirt between the sensor and the supporting surface is inhibited (at least during normal use). In some cases, in normal use, it may be possible to permit the passage of water (e.g. rainwater) between the sensor and the supporting surface without the performance of the sensor being affected. That may be the case, for example, when the sensor is provided with a superguard conductor as described in GB-A- 2,374,422.
- the said surface of the body may be an internal surface and/or may be inwardly-curved (i.e. concavely-curved).
- the surface may, for example, be the inwardly-curved internal surface of the bumper of a vehicle, in which case the use of the invention increases the range of vehicle bumpers in which the capacitive proximity sensor can be conveniently employed.
- the sensor can readily be employed in vehicle bumpers that curve about two axes (e.g., a vertical and a horizontal axis). In other words, the sensor can be employed in bumpers that have compound curvature, as well as those that are substantially flat or curve about a single axis only.
- the sensor mounting is such that the superguard conductor is located comparatively close to the inwardly-curved internal surface of the bumper.
- the sensor assembly may be provided in a vehicle bumper after manufacture, but may also be incorporated during the bumper manufacturing process.
- the present invention further provides a capacitive proximity sensor for mounting to a surface of a body to sense the presence of external objects, the sensor comprising a dielectric film substrate having front and rear major surfaces that, in use, face respectively outwards and inwards of the body, a sensor conductor on the front major surface, and a guard conductor on the rear major surface to provide an electrical shield for the sensor conductor; wherein the sensor substrate is pre-formed with bending lines along which the sensor can be bent to shape it for attachment to the said surface of the body.
- a sensor in accordance with this aspect of the invention can be mounted, for example, in a vehicle bumper using mechanical attachment means so that it closely follows the shape of the bumper.
- the invention further provides a method of making a vehicle bumper assembly comprising the steps of: providing a capacitive proximity sensor comprising a dielectric film substrate having a sensor conductor on the front major surface thereof, and a guard conductor on the rear major surface thereof to provide an electrical shield for the sensor conductor; providing a vehicle bumper, the inwardly-curved internal surface of which is so shaped that it does not provide a substantially flat area for direct attachment thereto of the sensor, at least in the sensor conductor region; locating the sensor inside the bumper with the front and rear major surfaces of the sensor directed respectively towards and away from the bumper; and mounting the sensor to the inwardly-curved internal surface of the bumper in such a manner that the ingress and retention of water/dirt between the sensor and the bumper is inhibited (at least during normal use of the vehicle) but the sensor is maintained in a substantially flat condition, at least in the sensor conductor region.
- a method of making a vehicle bumper assembly comprising the steps of: providing a vehicle bumper; providing a capacitive proximity sensor comprising a dielectric film substrate having a sensor conductor on the front major surface thereof, and a guard conductor on the rear major surface thereof to provide an electrical shield for the sensor conductor; providing a former shaped to fit to the curved internal surface of the bumper; positioning the sensor on the former, with the rear major surface of the sensor directed towards the former; and inserting the former into the bumper to position the sensor on the internal surface of the bumper.
- the former may be an infill for the bumper, which remains in place within the bumper after the sensor has been positioned on the internal surface of the bumper.
- the invention accordingly also provides a capacitive proximity sensor for mounting to a shaped surface of a body to sense the presence of external objects, the sensor comprising a dielectric film substrate having front and rear major surfaces that, in use, face respectively outwards and inwards of the body, a sensor conductor on the front major surface, and a guard conductor on the rear major surface to provide an electrical shield for the sensor conductor; the sensor being located on a former that is shaped to fit to the said shaped surface of the body whereby the former can be used to position the sensor on the said shaped surface.
- Fig. 1 shows a diagrammatic plan view of a major surface of a capacitive proximity sensor
- Fig. 2 shows an enlarged diagrammatic transverse cross-section of the sensor, taken on the line 2-2 of Fig. 1;
- FIG. 3 shows a diagrammatic plan view of the sensor mounted on the internal surface of a vehicle bumper
- FIG. 4 shows a diagrammatic transverse cross-section taken on the line 4-4 of
- Fig. 5 is similar to Fig. 3 but shows the sensor mounted in an alternative manner on the internal surface of the vehicle bumper;
- Fig. 6 shows a diagrammatic transverse cross-section taken on the line 6-6 of
- Fig. 7 is a diagrammatic plan view of a capacitive proximity sensor of the type shown in Figs. 1 and 2 with a differently- shaped substrate;
- Fig. 8 shows a diagrammatic transverse cross-section of the sensor of Fig. 7, taken on the line 8-8, mounted on the internal surface of a bumper;
- Fig. 9 shows a diagrammatic longitudinal cross-section of the assembly of Fig.
- Fig. 10 is similar to Fig. 3 but shows the sensor mounted in an alternative manner on the internal surface of the vehicle bumper;
- Fig. 11 shows a diagrammatic transverse cross-section taken on the line 11-11 of Fig. 10;
- Fig. 12 is a similar view to that of Fig. 11 but showing the sensor mounted in an alternative manner on the internal surface of the vehicle bumper;
- Figs. 13 and 14 are similar views to Figs. 3 and 4 respectively but show the sensor mounted in an alternative manner on the internal surface of the vehicle bumper;
- Figs. 15 is a diagrammatic plan view of another capacitive proximity sensor of the type shown in Figs. 1 and 2;
- Fig. 16 is an exploded diagrammatic transverse cross-section of the sensor of
- Fig. 15 taken on the line 16-16, mounted on the internal surface of a bumper;
- Fig. 17 is a diagrammatic illustration of a method of mounting a sensor of the type shown in Fig. 1 in a vehicle bumper;
- Figs. 18 to 20 are diagrammatic transverse cross-sections showing parts of other sensor assemblies in accordance with the invention.
- film substrate refers to an article having an extension in two directions which exceeds the extension in a third direction, which is essentially normal to said two directions, by a factor of at least 5 and more preferably by at least 10. More generally, the term “film” is used herein to refer to a flexible sheet-like material, and includes not only films but also sheetings, foils, strips, laminates, ribbons and the like.
- dielectric refers to materials having a specific bulk resistivity as measured according to ASTM D 257 of at least 1 x 10 12 ⁇ cm and more preferably of at least 1 x 10 13 ⁇ cm.
- electrically-conductive refers to materials having a surface resistivity as measured according to ASTM B 193-01 of less than 1 ⁇ /cm 2 .
- the capacitive proximity sensor 1 of Figs. 1 and 2 comprises a dielectric film substrate layer 2, the peripheral shape of which is determined by the intended location of the sensor as described further below.
- the substrate layer 2 is shown diagrammatically as being generally rectangular in shape.
- the front major surface of the substrate layer 2 shown in Fig. 1 carries a sensor conductor 6 and a superguard conductor 7 that are spaced apart on the surface of the substrate layer, and electrically-isolated from one another by the intervening substrate material.
- the superguard conductor 7 comprises a flat, electrically-conductive strip extending essentially along the length of the substrate layer 2.
- the sensor conductor 6 exhibits a more complicated design and comprises several, optionally-flattened, conductive strips 6a extending parallel to one another essentially along the length of the substrate layer 2 and, adjacent both ends of the strips 6a, several additional parallel (but shorter), optionally-flattened, electrically-conductive strips 6b forming lobe type regions.
- the strips 6a, 6b of the sensor conductor are connected together in both lobe regions by electrically-conductive strips 6c extending at an angle across the whole array of strips 6a, 6b. It will be appreciated that the particular configuration and number of the strips 6a, 6b and 6c shown in Fig. 1 is not essential and could be modified.
- the sensor conductor 6 and the superguard conductor 7 are both shown as being attached to the substrate layer 2 by an adhesive 6', 7', respectively.
- the rear major surface of the substrate layer 2, not visible in Fig. 1, carries a guard conductor 8 in the form of an electrically-conductive layer that preferably covers an area of the substrate corresponding in size at least to that occupied, on the other side, by the sensor conductor 6.
- the guard conductor 8 essentially fully covers the rear surface of the substrate layer 2 to which it is attached (in this case, by an adhesive 8a).
- the guard conductor 8 is electrically-isolated from the sensor and superguard conductors 6, 7 by the intervening dielectric substrate layer 2.
- the substrate layer 2 with the sensor conductor 6, the guard conductor 8 and the superguard conductor 7, can be attached to any suitable surface of a body, for example the inside of a bumper of a vehicle, to function as a capacitive proximity sensor.
- the substrate layer is positioned with the front major surface of Fig. 1 (i.e. the surface carrying the sensor and superguard conductors 6, 7) directed outwardly from the vehicle and the rear major surface (i.e. the surface carrying the guard conductor 8) directed inwardly towards the vehicle.
- the conductors 6, 7, 8 are connected to an electronic control unit (not shown) that can monitor the change that occurs in the capacitance between the sensor conductor 6 and (electrical) ground as the vehicle approaches an external object, and thereby provide an indication to the driver of the distance between the sensor conductor (and, hence, the vehicle) and the object.
- the guard conductor 8 acts as a shield to reduce the sensitivity of the sensor conductor 6 to anything behind it in the direction of the body of the vehicle, while an electrical signal is applied to the superguard conductor 7 to make the guard conductor 8 appear even bigger and so minimize the effect, on the signal from the sensor conductor 6, of water drops running over the outside of the bumper in rainy weather conditions.
- a capacitive proximity sensor of that type can be obtained from, for example, WO 01/08925and GB-A- 2 400 666 mentioned above, and from GB- A-2 374 422 (also of AB Automotive Electronics Ltd.).
- the measurement and processing of signals from a capacitive proximity sensor are described, for example, in WO 02/19524 (also of AB Automotive Electronics Ltd.).
- the entire sensor 1 can, if desired, be encased in a protective cover film (not shown).
- the surface of the body on which the sensor 1 is to be mounted is effectively flat or, if not flat, has a comparatively simple shape (for example, is curved in only one direction and/or has comparatively few irregularities)
- the surface on which the sensor is to be mounted will have a more complex shape (for example, it may be curved in two orthogonal directions and/or have irregularities such as projecting ribs) and considerable care will be required to prevent the formation of folds and creases in the sensor substrate layer 2 when it is being applied directly to the surface.
- Figs. 3 and 4 illustrate one way in which the sensor 1 can be attached to a shaped surface of a body without the formation of folds and/or creases in the substrate Iayer2 and without the need to cut the substrate layer 2 so that it can be tailored to fit the surface.
- the sensor 1 is attached to the internal surface 10 of a vehicle bumper 11 but it will be appreciated that the sensor could be attached in a similar way to other shaped surfaces.
- the sensor 1 is attached to the internal surface 10 of the vehicle bumper 11 only at the periphery 12 of the substrate layer 2 and, instead of following the inward curve of the bumper surface, extends in a substantially flat condition across the curve so that there is a gap 13 between the sensor and the bumper surface.
- the attachment of the periphery 12 of the sensor 1 to the bumper surface 10 can be effected in any suitable way (including, for example, by means of an adhesive or a weld) having regard to the nature of the substrate layer 2 and the surface to which it is being attached.
- suitable adhesives for attaching the periphery 12 of the sensor 1 to the bumper surface 10 include hot melt adhesives, for example the adhesive available under the trade designation "Jet-meltTM 3748 Adhesive” from 3M Company of St. Paul, Minnesota, USA and moisture/chemical curing adhesives, for example adhesives available under the trade designations "Scotch-WeldTM Structural Plastic Adhesives” and “Scotch-WeldTM Polyurethane Reactive Adhesives", also from 3M Company, while suitable welds include ultrasonic, fusion and laser welds.
- the attachment of the remainder of the sensor periphery 12 to the bumper surface may form a similar seal but, in some cases, it may be sufficient or preferable to attach the remainder of the sensor periphery to the bumper surface at spaced locations only.
- Figs. 5 and 6 show an assembly similar to that shown in Figs. 3 and 4 except that the sensor 1 is mounted on a non-metallic carrier substrate 15 having a larger surface area, with the rear face of the sensor located adjacent the carrier substrate.
- the carrier substrate rather than the sensor substrate layer 2, that is attached at its periphery 16 to the internal surface 10 of the vehicle bumper 11.
- the carrier substrate 15 could, for example, be a flexible film, a rigid injection-moulded component, a machined component, or an extruded polymeric sheet.
- the sensor 1 (or the larger substrate 15 on which it is mounted) is not attached directly at its periphery to the internal surface 10 of the bumper 11. Instead, the sensor is attached to the bumper by an attachment strip which has a flexible zone extending along its length at which the strip can bend to ensure the correct positioning of the sensor. Embodiments of that modification are illustrated in Figs. 18 to 20. [0047] In the embodiment illustrated in Fig. 18, the sensor 1 is attached to the internal surface 10 of a vehicle bumper 11 by an attachment strip 60 comprising two parts 61, 62 that are mechanically-interlocked along the length of the strip.
- the mechanical interlocking comprises a re-closable fastener 63 which permits the sensor 1 to be attached to, and removed from, the bumper 11 as required.
- hinges 64 are formed in the attachment strip 60, one along each side of the fastener 63 to provide increased flexibility.
- the re-closable fastener 63 may be of any suitable type, one example being a "press-to- close zipper" well known for use on plastic storage bags.
- One part 61 of the attachment strip 60 is secured by foam tape 65 around the periphery of the sensor 1 (or, in the case of an assembly as shown in Figs. 5 and 6, the periphery of the larger substrate 15 on which the sensor is mounted).
- the other part 62 of the attachment strip 60 is secured by foam tape 66 in an appropriate position on the internal surface 10 of the bumper 11, selected to ensure that the sensor 1 extends in a substantially flat condition across the curve of the bumper as described above with reference to Figs. 3 to 6.
- the hinges 64 in the attachment strip 60 provide additional flexibility to enable the attachment strip to accommodate the curves in the bumper including, in many cases, even the curves in the end sections of the bumper.
- the attachment strip 60 may not be necessary for the attachment strip 60 to extend around the entire periphery of the sensor: in some cases, for example, it may be sufficient to provide the attachment strip 60 only along the upper part of the periphery of the sensor.
- the attachment strip 60 can be formed, for example by extrusion, from any suitable polymeric material.
- the re-closable fastener 63 may be omitted if there is no need to remove the sensor 1 from the bumper, provided that the hinges 64 themselves impart sufficient flexibility to the attachment strip 60 to enable it to accommodate the curves in the bumper 11.
- the foam tapes 65, 66 used to secure the attachment strip 60 to the sensor and to the bumper can be replaced by any suitable alternative including, for example, other forms of adhesive tapes, adhesive layers, and welds.
- the attachment of the upper part of the sensor periphery to the bumper surface 10, in particular, should form a seal that prevents water and/or dirt penetrating between the sensor and the bumper.
- Fig. 19 illustrates a modification of the attachment system of Fig. 18.
- the part 62 of the attachment strip 60 is formed with a guidance channel 70 directly opposite the foam tape 66, in which an applicator roller (not shown) can be located to apply the foam tape 66 to the internal surface 10 of the bumper 11.
- the side 71 of the guidance channel adjacent the re-closable fastener 63 is formed with a lip 72 shaped to overhang the fastener and reduce the risk of moisture penetrating between the two parts of the fastener into the space between the sensor 1 and the bumper 11.
- guidance channel 70 is not restricted to attachment strips 60 incorporating re-closable fasteners: similar guidance channels could be used on attachment strips that do not incorporate re-closable fasteners, and could also be used on the substrate 15 of an assembly as shown in Figs. 5 and 6. In those cases, the lip 72 would not be required.
- the re-closable fastener 63 of Figs. 18 and 19 is omitted and the attachment strip 60 (which is now a one-piece component) is formed with a hinge section 75 that allows the attachment strip 60 to be folded in half along its length as illustrated, thereby decreasing the area of the internal surface 10 of the bumper 11 that is occupied by the attachment strip.
- Figs. 7 to 9 illustrate another way in which a capacitive proximity sensor 1 of the type shown in Figs. 1 and 2 can be attached to the internal surface 10 of a vehicle bumper 11, or to other shaped surfaces.
- the sensor 1 is mounted on (for example, laminated to) a carrier substrate 20, with the rear face of the sensor located adjacent the carrier substrate.
- the carrier substrate 20 differs from that of Figs. 5 and 6 in that it is specifically shaped and pre-formed with bending lines 21 so that it can be adapted to the shape of the bumper in both the vertical and horizontal directions.
- the bending lines 21 are placed so that they lie outside the area of the carrier substrate that is occupied by the sensor conductor 6 (and, preferably, outside or at the edge of the area occupied by the sensor 1), thereby allowing the carrier substrate to be adapted closely to the shape of the bumper while the sensor conductor (and, possibly, the whole of the sensor or at least a major part of it) remains in a substantially flat condition.
- the carrier substrate 20 can be attached to the bumper surface 10 by an adhesive or by welding as described above with reference to Figs 3 to 6. Alternatively, because the carrier substrate 20 in this case may follow the shape of the bumper quite closely, it may be possible to use clips 22 or some other form of mechanical attachment means to secure the carrier substrate to the bumper.
- the mechanical attachment means 22 may be formed as an integral part of the bumper 11 and arranged to locate in pre-formed attachment holes 23 in the carrier substrate 20, thereby facilitating attachment of the sensor 1 to the bumper.
- Figs. 7 to 9 results in a small gap between the sensor 1 and the internal surface 10 of the bumper 11, and is appropriate when the construction of the bumper reduces the risk of water and/or dirt entering and being retained in that gap.
- the construction of the bumper may, in some case, permit the passage of water (typically rain) through the gap but that may be acceptable particularly if the sensor 1 includes a superguard conductor as described above.
- Figs. 10 and 11 show the use of a pre-formed support 25 for the sensor 1, the support being shaped on one side 26 to fit to the internal surface 10 of the bumper 11 and on the other side to provide a substantially flat surface 27 on which the sensor 1 is mounted.
- the support 25 may be formed from any suitable material that can be provided with the required shape, preferably a low density material such as a closed cell polymeric foam material. Suitable materials are polyethylene, polyurethane, and polystyrene foams.
- the support can be formed in a mould having the same shape as the bumper 11, or by machining.
- the support 25 may then be attached to the internal surface 10 of the bumper 11 by an adhesive, and the sensor 1 may likewise be adhesively-bonded to the support.
- the sensor 1 may first be attached to the bumper (for example, as described above with reference to Figs. 3 and 4) and the material for the support then injected into the gap between the sensor and the bumper.
- Fig. 12 illustrates a further modification of the arrangement shown in Figs. 3 and 4, in which the sensor 1 is attached at its perimeter to the bumper surface 10 by an adhesive foam strip 30 which may be continuous or in several pieces.
- the foam strip 30 extends around the entire perimeter of the sensor but that is not essential. If required, a further foam strip 31 could be located in the gap 13 between the sensor 1 and the bumper 11 to provide additional support for the sensor. A similar foam strip 31 could be provided, if required, in the gap 13 between the sensor 1 and the bumper 11 in the arrangements shown in Figs. 3 to 6.
- the foam strips 30, 31 may, for example, be commercially-available adhesive foam tapes.
- FIG. 13 and 14 A further use of a foam strip to attach the sensor 1 to the bumper 11 is illustrated in Figs. 13 and 14.
- a wider adhesive foam tape 35 is employed across the upper part of the sensor 1, in the area in which the sensor conductor 6 is located, to attach the sensor to the internal surface 10 of the bumper.
- the foam tape 35 inhibits the ingress and retention of water/dirt between the sensor and the bumper surface 10 in the area of the sensor conductor and also maintains that area of the sensor in a substantially flat condition.
- the lower part of the sensor extends downwards towards the lower part of the bumper, hanging substantially freely and following the contours of the bumper surface 10.
- the lower part of the sensor 1 may be attached to the bumper surface 10, but only at spaced locations 36. The attachment at these spaced locations 36 may be made by patches of adhesive foam tape, or in any other suitable way.
- Figs. 15 and 16 illustrate a modification of the arrangement shown in Figs. 13 and 14, in which a reinforcing strip 40 is additionally provided along the top of the sensor 1 on its rear major surface.
- the reinforcing strip 40 advantageously acts to curve the sensor into the bumper and assist the attachment of the sensor to the bumper surface 10 via the foam tape 35.
- the reinforcing strip extends at each end beyond the sensor to provide locations at which it may be independently attached to the bumper 11.
- Fig. 16 shows, in cross-section, an exploded view of the sensor of Fig.
- Fig. 16 shows a patch of adhesive tape 46 for attaching the lower part of the sensor 1 to the bumper 11 , and a release liner 45 for protecting the adhesive 44 on the foam tape 35 until the sensor 1 is placed in position in the bumper.
- Fig. 17 illustrates a method of mounting a sensor 1 of the type shown in Figs. 1 and 2 on the inside surface 10 of a vehicle bumper 11. The method requires the use of a former 50, the front face 51 of which is shaped to correspond to the shape of the internal surface 10 of the bumper.
- the former 50 could be shaped in a mould having the same shape as the bumper 11, or by machining.
- the sensor 1 is positioned on the front face 51 of the former 50 with the rear major surface of the sensor (i.e. the guard conductor 8) adjacent the face 51, where it is held in place in any suitable way, for example by means of a comparatively low-strength adhesive. Because the front face 51 is convex, it is easier to position the sensor adhesively on this face than on the inwardly-curved internal face of the bumper 11, and the procedure may be assisted by the provision of location points on the face 51 if required.
- the front major surface of the sensor or the internal surface of the bumper is coated with an adhesive and the former 50 is then inserted into the bumper to deposit the sensor in the required position.
- the correct location of the sensor 1 can be achieved comparatively easily because the shape of the front face 51 of the former corresponds to that of the internal surface 10 of the bumper.
- the former 50 is then withdrawn and separates from the sensor 1 comparatively easily because the latter is now attached by a stronger adhesive to the bumper 11.
- the former 50 is preferably re-usable and is formed from a low-cost material that can readily be moulded to the internal shape of the bumper.
- the front face of the former at least, has a degree of resilience to assist in attaching the sensor 1 without the formation of noticeable folds and/or creases.
- a suitable material for the former is acrylonitrile-butadiene-styrene (ABS) copolymer. It is a further advantage if the sensor 1 can be stored on the former 50 in the required shape prior to use.
- the former 50 could be a foam infill intended to remain inside the bumper in which case the bond between it and the sensor would be of a permanent nature.
- an adhesive may be applied to the front face of the sensor 1 well in advance of the sensor being located in the bumper 11, in which case that adhesive may be protected by a release liner that is removed only when the sensor 1 is about to be attached to the internal surface 10 of the bumper.
- the superguard conductor 7 at the top of the sensor 1 is still located comparatively close to the internal surface of the bumper and consequently remains able to perform its intended function of minimizing the effect, on the sensor, of water drops running over the outside of the bumper in rainy weather conditions.
- capacitive proximity sensors may be used and may need to be attached to a shaped surface.
- proximity sensors can be used on any non- conductive panels such as door panels and bonnet lids for the purpose of detecting impending impacts and activating the appropriate safety mechanisms (e.g. air bags).
- Capacitive proximity sensors may be used in moving objects such as robot arms for controlling movement and preventing collisions, or in detectors for responding to moving objects (such as sensors for controlling automatic doors so that they respond to the approach of people or objects).
- Capacitive proximity sensors may also be used for detecting if a space is occupied, for example inside a vehicle to determine if an individual seat is occupied and activation, if necessary, of a warning signal to indicate that the corresponding seat belt is not being used.
- a further use of a capacitive proximity sensors is as a touch sensors that is activated when a person or object touches it either directly or through a thin insulator layer.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
- Switches That Are Operated By Magnetic Or Electric Fields (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN200880111262A CN101821133A (en) | 2007-10-10 | 2008-10-08 | Sensor module with capacitive proximity sensor |
EP08838447A EP2205466A2 (en) | 2007-10-10 | 2008-10-08 | Sensor assembly comprising a capacitive proximity sensor |
JP2010528988A JP2011501350A (en) | 2007-10-10 | 2008-10-08 | Sensor assembly having a capacitive proximity sensor |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0719807A GB0719807D0 (en) | 2007-10-10 | 2007-10-10 | Sensor assembly comprising a capacitive proximity sensor |
GB0719807.0 | 2007-10-10 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2009048910A2 true WO2009048910A2 (en) | 2009-04-16 |
WO2009048910A3 WO2009048910A3 (en) | 2009-05-28 |
Family
ID=38787941
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2008/079142 WO2009048910A2 (en) | 2007-10-10 | 2008-10-08 | Sensor assembly comprising a capacitive proximity sensor |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP2205466A2 (en) |
JP (1) | JP2011501350A (en) |
KR (1) | KR20100085969A (en) |
CN (1) | CN101821133A (en) |
GB (1) | GB0719807D0 (en) |
WO (1) | WO2009048910A2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012031728A3 (en) * | 2010-09-10 | 2012-07-05 | Brose Fahrzeugteile Gmbh & Co. Kg, Hallstadt | Capacitive distance sensor |
US20210178606A1 (en) * | 2018-07-18 | 2021-06-17 | Fogale Nanotech | Apparatus having a capacitive sensing system and electric line(s) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101120700B1 (en) | 2010-09-02 | 2012-03-29 | 삼성메디슨 주식회사 | Ultrasound system and method for providing color doppler mode image |
JP6265420B2 (en) * | 2014-03-19 | 2018-01-24 | 本田技研工業株式会社 | Vehicle bumper |
GB2539659B (en) * | 2015-06-22 | 2019-05-01 | Octo Telematics Spa | Collision Diagnosis for a Traffic Event |
GB2542200B (en) | 2015-09-14 | 2018-12-26 | Jaguar Land Rover Ltd | Sensor and method |
CN105172727A (en) * | 2015-10-14 | 2015-12-23 | 苏州新协力特种工业模板有限公司 | Bumper capable of realizing early warning of collisions |
JP6729414B2 (en) * | 2017-01-18 | 2020-07-22 | 株式会社デンソー | Vehicle collision detection device |
JP7109562B2 (en) * | 2018-09-14 | 2022-07-29 | アルプスアルパイン株式会社 | Proximity detection system |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6441623B1 (en) * | 1999-07-29 | 2002-08-27 | Ab Automotive Electronics Ltd. | Capacitive proximity sensor for automotive use |
GB2376075A (en) * | 2001-06-01 | 2002-12-04 | Ab Automotive Electronics Ltd | Bumper proximity detector using capacitive sensor |
US6879250B2 (en) * | 2001-04-04 | 2005-04-12 | Compagnie Plastic Omnium | For a motor vehicle, an outside element providing a capacitive sensor, and a piece of bodywork including such an outside element |
WO2006092627A1 (en) * | 2005-03-02 | 2006-09-08 | Ab Automotive Electronics Ltd | Capacitive sensor and method of production |
-
2007
- 2007-10-10 GB GB0719807A patent/GB0719807D0/en not_active Ceased
-
2008
- 2008-10-08 KR KR1020107010066A patent/KR20100085969A/en not_active Application Discontinuation
- 2008-10-08 WO PCT/US2008/079142 patent/WO2009048910A2/en active Application Filing
- 2008-10-08 JP JP2010528988A patent/JP2011501350A/en not_active Withdrawn
- 2008-10-08 CN CN200880111262A patent/CN101821133A/en active Pending
- 2008-10-08 EP EP08838447A patent/EP2205466A2/en not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6441623B1 (en) * | 1999-07-29 | 2002-08-27 | Ab Automotive Electronics Ltd. | Capacitive proximity sensor for automotive use |
US6879250B2 (en) * | 2001-04-04 | 2005-04-12 | Compagnie Plastic Omnium | For a motor vehicle, an outside element providing a capacitive sensor, and a piece of bodywork including such an outside element |
GB2376075A (en) * | 2001-06-01 | 2002-12-04 | Ab Automotive Electronics Ltd | Bumper proximity detector using capacitive sensor |
WO2006092627A1 (en) * | 2005-03-02 | 2006-09-08 | Ab Automotive Electronics Ltd | Capacitive sensor and method of production |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012031728A3 (en) * | 2010-09-10 | 2012-07-05 | Brose Fahrzeugteile Gmbh & Co. Kg, Hallstadt | Capacitive distance sensor |
US20130193989A1 (en) * | 2010-09-10 | 2013-08-01 | Brose Fahrzeugteile Gmbh & Co. Kg, Hallstadt | Capacitive distance sensor |
EP2809005A1 (en) * | 2010-09-10 | 2014-12-03 | Brose Fahrzeugteile GmbH & Co. Kommanditgesellschaft, Hallstadt | Capacitive distance sensor |
KR101512712B1 (en) * | 2010-09-10 | 2015-04-16 | 브로제 파초이크타일레 게엠바하 운트 콤파니 케이지, 할스타드 | Capacitive distance sensor |
US9702682B2 (en) | 2010-09-10 | 2017-07-11 | Brose Fahrzeugteile Gmbh & Co. Kg, Bamberg | Capacitive distance sensor |
US10677579B2 (en) | 2010-09-10 | 2020-06-09 | Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Bamberg | Capacitive distance sensor |
US20210178606A1 (en) * | 2018-07-18 | 2021-06-17 | Fogale Nanotech | Apparatus having a capacitive sensing system and electric line(s) |
Also Published As
Publication number | Publication date |
---|---|
GB0719807D0 (en) | 2007-11-21 |
KR20100085969A (en) | 2010-07-29 |
EP2205466A2 (en) | 2010-07-14 |
CN101821133A (en) | 2010-09-01 |
WO2009048910A3 (en) | 2009-05-28 |
JP2011501350A (en) | 2011-01-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2205466A2 (en) | Sensor assembly comprising a capacitive proximity sensor | |
US20100117660A1 (en) | Cable for a capacitive proximity sensor | |
US20090045824A1 (en) | Proximity sensor with an edge connection, and method for manufacturing the same | |
EP0898524B1 (en) | Vehicle instrument panel with seamless airbag cover | |
EP1697178B1 (en) | Vehicular bumper structure | |
EP1787871B1 (en) | System for capacitive detection of a seat occupancy | |
AU749401B2 (en) | Instrument panel for air bag | |
US20080297176A1 (en) | Capacitive Sensor and Method for Manufacturing the Same | |
US7992891B2 (en) | Interior panelling part for covering an airbag and method for production thereof | |
JP5126271B2 (en) | Long sensor | |
US20060261635A1 (en) | Automobile door assemblies | |
CN104228731B (en) | In conjunction with vehicle sensors assembly | |
US9139148B2 (en) | Bonded and rotatable vehicle sensor assembly | |
US20210363808A1 (en) | Bodywork part with integrated anti-pinching system | |
CN104512364A (en) | Bonded and rotatable vehicle sensor assembly | |
WO2001008925A1 (en) | Capacitive sensor | |
CN103569214B (en) | Vehicle mudguard | |
RU2264310C2 (en) | Surface edge protective cover plate | |
GB2400666A (en) | Capacitive proximity sensor | |
US9114769B1 (en) | Vehicle sensor assembly with lever assist | |
US20070246918A1 (en) | Instrument panel with integral hidden door cover and method of manufacture thereof | |
EP2576292B1 (en) | Attachable fix point strip | |
EP2358570B1 (en) | Sound insulation | |
WO2008088333A1 (en) | Capacitive proximity sensor with connector tongue | |
MX2008008980A (en) | Proximity sensor with connection hole, and method for manufacturing the same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200880111262.8 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 08838447 Country of ref document: EP Kind code of ref document: A2 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1973/CHENP/2010 Country of ref document: IN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010528988 Country of ref document: JP |
|
NENP | Non-entry into the national phase in: |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2008838447 Country of ref document: EP |
|
ENP | Entry into the national phase in: |
Ref document number: 20107010066 Country of ref document: KR Kind code of ref document: A |