EP1442189A1

EP1442189A1 - Device for opening and closing a mobile element

Info

Publication number: EP1442189A1
Application number: EP02787341A
Authority: EP
Inventors: Achim Neubauer; Martin-Peter Bolz; Jochen Moench; Falk Herrmann
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2001-10-23
Filing date: 2002-10-08
Publication date: 2004-08-04
Anticipated expiration: 2022-10-08
Also published as: EP1442189B1; WO2003038221A1; US7362040B2; US20040070316A1; ATE363578T1; DE10151556A1; DE50210246D1

Abstract

The invention relates to a device for opening and closing an opening (11), especially on a vehicle, by means of a motor-driven, mobile element (10). The inventive device comprises a control unit (26) and an anti-pinch sensor (14) that is substantially disposed along an edge (20) of the element (10) and/or the frame profile (12) limiting the opening (11) and that detects an obstacle (24) in the path of adjustment of the element (10) when the element (10) is closed, and that forwards a signal to the control unit (26) to stop or reverse the movement of the element (10). Said anti-pinch sensor (14) comprises a highly elastic electroactive polymer (EAP) material (30), especially polyurethane, fluoroelastomer, polybutadiene, fluorosilicone or silicone disposed between the electrodes (28, 34, 36) and effecting a change in voltage o the electrodes (28, 34, 36) when deformed.

Description

Device for opening and closing a moving part

State of the art

The invention relates to a device for opening and closing a movable part according to the preamble of the independent claim.

With DE 199 13 106 Cl Einkle mschutz with a hollow profile for a power-operated locking device is known, in which a shaped as a hollow profile terminal block along a frame, for example a sunroof opening, is arranged. The hollow profile has two electrically conductive areas spaced apart from one another, the contact of which triggers a switching process for actuating the motor of the closing device. Here is the

The production of such a profile is very complex and, in use, such a system is susceptible to false tripping, caused by the permanent deformation of the electrically conductive areas.

Advantages of the invention

The device according to the invention with the features of claim 1 has the advantage that the highly stretchable, electroactive polymer (EAP) material reliably and easily when a small pressure is exerted thereon measurable voltage change on the electrodes applied to the EAP material. The design of the anti-trap sensor is very simple and insensitive to faults, since the system is based on the electroactive material properties of the EAP material. In addition, EAP materials are inexpensive to manufacture and process, so that, according to the invention, extremely cost-effective and reliable protection against pinching is possible with different geometric sensor shapes.

L O

Advantageous developments of the device according to the invention are possible due to the features listed in the subclaims. The electroactive properties of the EAP material are based on an effective one

L5 Extension or alignment of the polymer chains by appropriate external deformation of the EAP material. Depending on the force acting on the EAP material and the arrangement of the electrodes on the EAP material, a voltage increase or a voltage reduction is then carried out

> 0 caused.

It is particularly expedient to form the EAP material into thin layers with a thickness of, for example, 1-100 micrometers, since here, in particular with vertical ones

! 5 The force applied to the EAP material is stretched by up to 300% even with a small external force, thus producing a correspondingly high change in tension. The thinly shaped layers can also be arranged particularly easily along the edge of the part or the frame profile, for example on or within a sealing lip.

EAP materials are characterized by a change in stress according to Formula 5

U = t ^* • (p / εr * ε0),. The magnitude of the change in voltage can thus be predetermined quite advantageously by the choice of the thickness t of the EAP material.

If several EAP layers, each equipped with electrodes, are arranged one above the other and are virtually connected in series, the individual voltage changes add up, which enables a simpler signal evaluation due to the higher measurement signal.

It is advantageous to arrange the at least one EAP layer approximately perpendicular to the expected clamping force, since this results in the greatest possible deformation of the material and thus a maximum change in stress.

Alternatively, arrangements are also conceivable in which several EAP layers are arranged approximately parallel to the adjustment plane of the part. The clamping force then acts approximately parallel to the EAP layers and changes their surface area, which is correlated with a change in the thickness of the layers. The electrodes can be arranged both between the EAP layers and on the end faces of the EAP layers.

If one or more EAP layers - optionally also with insulating layers in between - are wound up as a roll, this arrangement can detect all forces in the plane perpendicular to the roll in the same way. Such a roller can therefore be arranged particularly advantageously along the seal of a frame.

With such an arrangement of the roll approximately parallel to the edge of the part or the frame, the electrodes are advantageously formed as layers between the wound EAP layers. Alternatively, the electrodes can also be on the end faces of such Roll or tube to be arranged, this is particularly advantageous for a subdivision of the anti-trap sensor along the edge or the frame profile in order to be able to detect an obstacle in a spatially resolved manner. 5

The arrangement of the at least one EAP layer directly above or below a perforated band matrix is advantageous. With this matrix, spatially fixed support points are created, with the EAP layer changing due to a

L0 applied basic voltage arches through the holes of the perforated tape matrix. This ensures that sufficient deformation of the EAP layer occurs even when relatively small obstacles occur, since with this arrangement a local force effect does not occur over a large area

L5 of the EAP layer can be compensated.

In order to create a spatially flexible and thus locally sensitive anti-trap sensor, at least one of the electrodes is spatially structured. It is particularly advantageous here if the electrode has a high degree of flexibility along the edge of the part or the frame, because it also reliably detects smaller obstacles.

If the at least one electrode of the at least one EAP-25 layer is subdivided into a plurality of electrodes which are insulated from one another, a sensor with spatial resolution, in particular along the edge of the part or the frame, can thus be implemented in a simple manner.

It is advantageous if two polymer films are coated in such a way that the structured electrodes are enclosed in the middle. This ensures that the effective electrode surfaces are directly one above the other without adjustment. When the typically very narrow conductor tracks are integrated in the sensor 55, they are additionally mechanically protected. In order to ensure complete detection of an obstacle, the different independent sensors, in particular along the edge or the frame, can spatially overlap. If each independent 5 sensor area has its own electrode, the sensitivity of the sensor can be individually adjusted locally using an adapted, specified basic voltage.

L0 The arrangement of the

Anti-trap sensor between the sealing profile and the frame profile of an opening. The sensor can be glued in or just clamped in without a design change to the previous seal or

L5 frame profiles is necessary.

The spatially subdivided electrodes can be realized particularly favorably by means of a printed circuit board technology, the individual electrodes with their

20 voltage tapping conductors are arranged as a thin layer on a thin, flexible circuit board foil.

The mutual use of the top and bottom of the sensor for routing the conductor allows particularly space-saving

25 Version of the sensor.

In terms of production technology, it is favorable to attach the anti-trap sensor to the frame or sealing profile with a film, the conductor tracks for the 30 connections of the electrodes preferably being arranged on the film. This method enables a spatially fine subdivision of the sensor into areas with independent pairs of electrodes.

Since the EAP materials have very similar properties to the 35 materials of a sealing profile, the EAP layers can be integrated into the sealing profile particularly cheaply and manufacture in one operation with the same, for example by means of co-extrusion or multi-component injection molding.

Applying the EAP layer to the sealing profile in the form of a lacquer or by gluing is also an inexpensive alternative. Anti-trap sensors manufactured in this way are also very hard-wearing against mechanical stress due to the rubber-like properties of the EAP materials, even over a wide temperature range from -50 ° C to 200 ° C.

By arranging the at least one EAP layer semicircularly around one end of the frame profile, pinching forces that are outside the plane of movement of the

Partly act on the sealing profile, be sensed safely.

Due to the spatial resolution of the anti-trap sensor along the edge or the frame, areas of different sensitivity can easily be specified, which are adapted to certain edge sections of the part. The geometrical shape of the part and the corresponding frame can be taken into account, which causes pinching force components that deviate from the closing direction.

The sensitivity of the individual sensor areas can advantageously be realized by applying an individually adapted working voltage to the electrodes of the corresponding areas.

Since the voltages applied to EAP materials are typically in the kV range, the signals from the electrodes are fed to a DC / DC converter which is part of an evaluation device in a control unit of the anti-pinch sensor. drawing

Exemplary embodiments of a device according to the invention are shown in the drawings. Show it

FIG. 1 shows an arrangement of an anti-trap sensor on a motor vehicle side window,

L0

2a to 2c the principle of operation of the device according to the invention,

3 and FIGS. 4a to 4c show different exemplary embodiments of a pinch protection sensor according to the invention,

FIG. 5 shows a further exemplary embodiment with a perforated band matrix,

> 0 Figures 6 and 7 different embodiments of electrodes of a device according to the invention and

8 and FIG. 9 further possible arrangements of the anti-trap sensor on a frame profile according to FIG. 1.

> 5

Description of the embodiments

In Figure 1, a side window of a motor vehicle is shown, wherein between a window 10 as

SO movable part 10 and a frame profile 12 enclosing a window opening 11, an anti-trap sensor 14 is arranged over the entire length thereof. The anti-trap sensor 14 is integrated, for example, in a sealing profile 16 and in different areas 18,

15 divided according to the shape of the disc 10. The

Disk 10 has an edge 20 that is substantially runs parallel to the frame profile 12. When the part 10 is closed, a closing force 22 occurs, the component of which can be of different sizes perpendicular to the edge 20 of the part 10 in the different regions 18. Is located . an obstacle 24 in the adjustment path between the part 10 and the frame profile 12, pressure is exerted on the anti-trap sensor 14 when closing, and a signal is forwarded to a control unit 26 of the locking device. If a preset threshold value of the closing force 22 is exceeded, the motor 21 receives a control command to stop the part 10 or to reverse its direction of movement.

Figure 2a to 2c shows a schematic cross section of an anti-trap sensor 14, the several electroactive

Has polymer (EAP) layers. The EAP material used is, for example, polyurethane PT6100S, fluoroelastomer LaurenL143HC, polybutadiene Aldrich PBD, fluorosilicone 730 or silicone Sylgard 186. EAP materials have the special property that due to their

Electrostriction in the event of external deformation changes the effective length of the electroactive, dielectric polymer chains. This change in length causes a change in voltage at the electrodes 28 arranged on the EAP layers. In FIG. 2a, a first EAP layer 30 is arranged on a rubber of a sealing profile 16 between two electrode layers 28. Another layer sequence electrode, EAP layer, electrode is arranged above this first electrode / EAP packet, separated by an insulation layer 32. The two electrodes 34 are grounded and a positive voltage is applied to each of the other two electrodes 36. The thickness 38 of the EAP layer 30 is, for example, between 1 and 100 micrometers. The thinner this layer is, the more it can be stretched, which increases the sensitivity of the pinch protection. FIG. 2b shows the deformation of the EAP layers 30 due to a jammed obstacle 24. The jamming force 22 causes the EAP layers 30 to be lengthened along the sealing profile 16. The EAP layers 30 experience one

Cross contraction, which reduces their thickness 38. This leads to a voltage change between the two pairs of electrodes 34, 36, which corresponds to a specific force acting on the anti-trap sensor 14. 10 The change in voltage is measured in the control unit 26 and compared with a limit value, the motor 21 of which is stopped or reversed when it falls below or falls below it. The voltage change takes place according to the formula

L5 U = t * V (p / εr * ε0), wherein the voltage change caused is directly proportional to t, the thickness 38 of the EAP layer 30. The pressure P generated by the clamping force 22 of an obstacle 24 and the dielectric material properties ε _r and

_0 ε _Q influence the voltage change only as a factor under the root.

In FIG. 2c, the anti-trap sensor 14 is arranged in a cavity 39 of the sealing profile 16, which extends approximately 25 parallel to the edge 20.

An alternative embodiment of the anti-trap sensor 14 is shown in FIG. Here, too, an EAP layer 30 is arranged between two flat electrodes 28 10, four EAP layers 30 with electrodes 28 lying between them being combined to form a package on the right. However, the closing force 22 does not act perpendicular to the EAP layers 30 and the electrodes 28, but rather in the layer plane of the EAP layers 30. This 5 force effect also causes a change in the shape of the EAP layers 30, which leads to a thickening thereof. A voltage change, which is correlated with the closing force 22, is again tapped at the electrodes 28 arranged between the EAP layers 30. In this embodiment of the anti-trap sensor 14, the EAP layers 30 are arranged between the frame profile 12 and the pane 10 in parallel to their direction of movement. The addition of the individual voltage changes leads in a simple manner to an increase in the measurement signal when using several EAP layers 30.

10

In a further exemplary embodiment according to FIG. 4, a layer sequence of electrode 28, EAP layer 30, electrode 28, EAP layer 30 is wound around a winding core 40 to form a roll 42, the latter being axially approximately parallel

L5 extends to edge 20. When the part 10 is closed, the anti-trap sensor 14 experiences a radial force as soon as an obstacle 24 presses on it. The EAP layers 30 - at least those layers perpendicular to the closing force - are compressed in such a way that the thickness 38 of the EAP layers 30 decreases. This also leads to an accumulated voltage change, which is tapped off at the two electrodes 28.

In FIG. 4b, an EAP layer 30 is also wound up with> 5 intermediate electrodes 34, 36 analogous to FIG. 4a, but in this arrangement the force is applied in the axial direction to the roller 42. In this case, several rollers 42 with their axes are approximately in the plane of the disk and arranged approximately perpendicular to the edge 20,> 0 whereby an axial change in length of the roller 42 causes a change - in this case an increase - in the thickness 38 of the EAP layers 30.

FIG. 4c shows a further variation in which the EAP-5 layer 30 is shaped as a simple tube 44, the electrodes 34, 36 being located at the two axial ends of the Tubes 44 are arranged. According to FIG. 4b, the force is also applied axially, which also changes the thickness 38 of the EAP layer 30. The electrode arrangement does not measure the change in voltage across the thickness 38 of the EAP layer 30, but rather via its axial extent.

FIG. 5 shows a further embodiment of the anti-trap sensor 14 according to the arrangement in FIG. 2. In this case, an EAP layer 30 embedded between two electrodes 34, 36 is arranged over a perforated band matrix 46. Between the individual holes 48 of the perforated band 46, which extends approximately parallel to the edge 20, there are support points 50 at which the EAP layer 30 is suspended. The perforated band matrix 46 represents a spatially fixed scaffold, through the holes 48 of which, when the voltage is applied to the electrodes 34, 36, the EAP layer 30 together with the electrodes 34, 36 extends through it. The perforated band matrix 46 is integrated together with the electrodes 34, 36 and the EAP layer 30 in a sealing profile 16 or is produced directly in one piece with it by means of multi-component injection molding. Due to the spatially fixed support points 50, even small obstacles 24 cause a relatively strong deformation of the EAP layer 30, since this is pushed back through the holes 48 up to the plane 52 of the perforated band matrix 46. This causes a voltage change between the adjacent electrodes 34, 36, which is evaluated to trigger the pinch protection function.

FIG. 6 shows an anti-trap sensor 14 with one and with two EAP layers 30, one electrode 56 each having a structure. The electrode 56 is divided along the edge 20 or the frame profile 16 into small sections which are connected to one another by flexible connecting pieces 54. The structured electrode 56 is designed as an integrated layer and can have different geometric shapes. Such an electrode 56, which is arranged on or between EAP layers, is very flexible and extraordinarily stretchable, even with a one-piece design, and is therefore very wear-resistant.

FIG. 7 shows an exemplary embodiment of a sensor 14 with a one-piece, unstructured base electrode 34 and an EAP layer 30 arranged thereon. In turn, a structured electrode 56 is arranged as an integrated layer, the individual electrode sections 58 being insulated from one another. The individual electrode sections 58 have conductor tracks 62 for contacting, which are likewise part of the integrated layer. The electrode sections 58 are preferably subdivided in the direction 20 ^{λ of} the edge 20 in order to locally increase the sensitivity of the anti-trap sensor 14 or else to realize a division into areas 18 in accordance with the disk contour according to FIG. 1. If the base electrode 34 is connected to ground, an individual base voltage for the respective electrode section 58 - or corresponding to the sensor areas 18 - can be assigned to each individual electrode section 58. As a result, a different sensitivity of the sensor 14 can be set for each section 58 or area 18. Alternatively, such a local sensitivity can also be set using different threshold values for the voltage change.

FIG. 8 shows a cross section through a frame profile 12 with a sealing profile 16. The EAP layer 30 arranged between two electrode layers 28 is arranged in a circle around a free end 60 of the frame profile 12 between the latter and the sealing profile 16. Due to the semicircular shape of the anti-trap sensor 14 in In a plane approximately perpendicular to the edge 20, pinching forces 22 can also be detected outside the plane of movement of the part 10, the inner region 15 of the pinch protection sensor 14 towards the pane 10 being decisive for the timely detection of an obstacle 24. In this arrangement, the anti-trap sensor 14 is glued onto the free end 60 of the sealing profile 12, but can also only be inserted into the sealing profile 16 before it is installed and pressed against the free end 60.

In FIG. 9, the anti-trap sensor 14 is fixed to a free end 60 of the frame profile 12 by means of a film 64 which carries the conductor tracks 62 for the individual electrode section 58. If the entire length of the anti-trap sensor 14 is divided into many sections 58, a large area is required for the large number of electrode connections in order to supply the conductor tracks 62 to a voltage source along the frame profile 12. The flexible printed circuit board film 64, which extends over the entire area between the outside 66 of the sealing profile 12 and the sealing profile 16, serves this purpose. The EAP layers 30 and the associated electrodes 28 are preferably an integral part of the circuit board film 64. The circuit board film 64 with the conductor tracks 62 is either glued to the sealing profile 16 or is only pressed in between the sealing profile 16 and the frame profile 12. The contact tracks 62 are preferably fed to a control unit 26, in which the applied voltages in the kV range are transformed by means of a DC / DC converter for further processing in the evaluation electronics. To the

Electrodes 28 have currents of the order of 0.5 mA, so that even high voltages do not pose a risk to people. The local change in length of the EAP layer 30 by up to 300% takes place in accordance with the closing speed of the part 10. The reaction time of the electrostriction, that is to say the generation of a voltage change in the case of a applied working voltage, takes place in the range of milliseconds to microseconds. Electrostriction can also be represented using the model of a capacitor, the EAP material being arranged as a dielectric between two flat electrode plates. Through the outside

Deformation occurs due to changes in the system's impedance, since the effective length of the polymer chains or the orientation of the internal dipoles in the applied electrical field changes. The multiple stacked EAP layers can be connected in series to increase the measurement signal. The thinner the EAP films can be applied, the lower the current losses due to the heat given off by the electrodes. Enclosing the structured electrode 56 between two EAP layers ensures that the effective electrode surfaces are located directly above one another without adjustment. When the typically very narrow conductor tracks 62 are integrated into the sensor, they are additionally mechanically protected. When producing the EAP layers 30, care must be taken to ensure that the layer thickness 38 is homogeneous, since otherwise a constant, homogeneous electric field cannot be applied. Since the sensor material has very similar mechanical properties to the material of the sealing profile 16, delamination between the sensor 14 and the rubber is minimized. This applies to a temperature range from -50 to 200 ° C, which completely covers the application in the automotive sector. Therefore, the inventive design of the anti-trap sensor 14 can also be applied to the sealing profile 16 in a simple form as a lacquer.

It is also conceivable that, for example, the size of the pinched object 24 can be deduced from the course of the impedance changes and thus the triggering threshold value can also be determined depending on the object size.

Claims

claims

1. Device for opening and closing an opening (11), in particular on a vehicle, by means of a motor-driven, movable part (10), with a control unit (26) and an anti-trap sensor (14), which essentially extends along an edge (20 ) of the part (10) and / or a frame profile (12) delimiting the opening (11) and when closing the part (10) detects an obstacle (24) that is in the adjustment path of the part (10), and a Forwards the signal to the control unit (26) in order to stop or reverse the movement of the part (10), characterized in that the anti-trap sensor (14) is a highly stretchable electroactive polymer (EAP) arranged between electrodes (28, 34, 36). Material (30), in particular polyurethane, flour elastomer, polybutadiene, fluor silicone or silicone, which causes a change in voltage at the electrodes (28, 34, 36) when deformed.

Device according to claim 1, characterized in that when the EAP material (30) is deformed, the effective length of its polymer chains changes.

3. Device according to claim 1, characterized in that the EAP material (30) is formed in thin layers, in particular a thickness (38) of 1 to 100 microns.

5 4. Device according to claim 1, characterized in that on the electrodes (28, 34, 36) a voltage U according to the formula

U = t * (p / εr * ε0) l / 2 0, where t is the thickness (38) of the EAP layer (30), ε _{r is} the dieelectricity number, & Q the electric field constant and P that of the obstacle (24) generated pressure on the EPA layer (30).

5 5. Device according to one of claims 1 to 4, characterized in that a plurality of EAP layers (30) with electrodes (28, 34, 36) and / or insulation layers (32) in between are stacked one above the other.

6. Device according to one of claims 1 to 5, characterized in that the pressure generated by the obstacle (24) acts predominantly perpendicular to the EAP layers (30).

5 7. Device according to one of claims 1 to 5, characterized in that the pressure generated by the obstacle (24) mainly acts parallel to the EAP layers (30).

SO

8. Device according to one of claims 1 to 7, characterized in that the at least one EAP layer (30) is formed as a tube (44) or as a roller (42).

9. Device according to one of claims 1 to 8, characterized in 5 that the electrodes (28, 34, 36) to the End faces or on the outer surfaces of the tube (42) or the roller (44) are arranged.

10.Device according to one of the preceding claims, characterized in that the at least one EAP layer (30) is arranged over a perforated tape matrix (46) and is applied to the electrodes (28, 34, 36) through the holes (48 ) of the perforated band matrix (46) extends through.

11.Device according to one of the preceding claims, characterized in that the at least one of the electrodes (28, 34, 36, 56) is spatially structured, in particular is designed to be easily movable in the direction (20X of the edge (20).

12.Device according to one of the preceding claims, characterized in that the anti-trap sensor (14) along the edge (20) or the frame profile (12) is divided into several independent areas (18, 58).

13.Device according to one of the preceding claims, characterized in that the areas (18, 58) of the anti-trap sensor (14) overlap.

14.Device according to one of the preceding claims, characterized in that each sensor area (18, 58) has at least one electrode (28, 34, 36, 56).

15.Device according to one of the preceding claims, characterized in that the individual electrodes (28, 34, 36, 56) of the sensor regions (18, 58) in the form of an integrated layer with conductor tracks (62) on the EAP layer (30) are executed.

16.The device according to one of the preceding claims, characterized in that the anti-trap sensor (14) is arranged between a frame profile (12) enclosing the part (10) and a sealing profile (16) inserted therein.

17.Device according to one of the preceding claims, characterized in that the anti-trap sensor (14) is fixed by means of a film (64), the conductor tracks (62) for controlling the electrodes (28,

34, 36, 56).

18. Device according to one of the preceding claims, characterized in that the anti-trap sensor (14) is integrated in the sealing profile (16), in particular is formed in one piece with the sealing profile (16) by means of coextrusion or multi-component injection molding.

19.Device according to one of the preceding claims, characterized in that the at least one EAP

Layer (30) in the form of a lacquer or by gluing on the sealing profile (16) is arranged.

20.Device according to one of the preceding claims, characterized in that the anti-trap sensor

(14) is shaped like a semi-circle around at least one free end (60) of the frame profile (12) facing the part (10).

21.Device according to one of the preceding claims, characterized in that the anti-trap sensor (14) along the edge (20) or the frame profile (12) is divided into areas (18, 58) of different sensitivity, which one of the geometry of the edge (20 ) assigned threshold value of the voltage change is whose exceeding or falling below triggers a stopping or reversing of the part (10).

22. Device according to one of the preceding claims, characterized in that to the individual EAP

Different output voltages are applied to layers (30) or sensor regions (18, 58) associated with electrodes (28, 34, 36, 58).

23.Device according to one of the preceding claims, characterized in that the anti-pinch sensor (14) for evaluating the voltage change in the control unit (26) has a DC-DC converter (27).