DEVICE FOR LOCKING A WIPER BLADE TO A DRIVE ARM
20180326949 · 2018-11-15
Assignee
Inventors
- Julien Carrion (Issoire, FR)
- Laurent Andre-Masse (Issoire, FR)
- Geoffrey Bayard (Issoire, FR)
- Christophe Chassaing (Issoire, FR)
- Grégory Kolanowski (Issoire, FR)
- Chantal Marquet (Issoire, FR)
- Gilles Petitet (Issoire, FR)
Cpc classification
B60S1/4038
PERFORMING OPERATIONS; TRANSPORTING
B60S1/4048
PERFORMING OPERATIONS; TRANSPORTING
B60S1/0491
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
Device for locking a windshield wiper (10) to a drive arm (12), characterized in that it comprises electrical means (4) able to drive a reversible movement of at least one locking element (5) secured to the arm (12) or to the wiper (10), said at least one locking element (5) moving relative to the arm (12) or to the wiper (10) to which it is secured between an unlocked position in which said at least one locking element (5) is secured only to the arm (12) or to the wiper (10) and a locked position in which said at least one element (5) is secured to the arm (12) and to the wiper (10).
Claims
1. A device for locking a windshield wiper to a drive arm, the device comprising electrical means that drive a reversible movement of at least one locking element secured to the arm or to the wiper, said at least one locking element moving relative to the arm or to the wiper to which the at least one locking element is secured between an unlocked position in which said at least one locking element is secured only to the arm or to the wiper and a locked position in which said at least one locking element is secured to both the arm and to the wiper.
2. The device as claimed in claim 1, wherein the electrical means are able to actuate in translation a piston, the movement of said piston driving movement of said at least one locking element.
3. The device as claimed in claim 2, wherein said piston is the core of an electromagnet, said core being movable in translation by the magnetic field produced by the electromagnet.
4. The device as claimed in claim 2, wherein said piston is part of a device enabling movement of the piston by an electric current.
5. The device as claimed in claim 2, wherein, in the unlocked position, said at least one locking element is secured to a connector of the wiper and wherein, in the locked position, said at least one locking element is secured to the connector and to an end part of the arm.
6. The device as claimed in claim 5, wherein said at least one locking element comprises at least one rod able to be engaged in the locking position in an opening of said end part and to be held at a distance from said opening in the unlocked position.
7. (canceled)
8. The device as claimed in claim 6, wherein said at least one rod is movable in translation in a direction substantially orthogonal to the direction of movement of the piston.
9. The device as claimed in claim 5, wherein said at least one locking element comprises a leaf spring of which at least one end is engaged in an opening of the end part of the arm in the locked position.
10.-14. (canceled)
15. The device as claimed in claim 5, wherein said at least one locking element comprises a toothed shaft driven in rotation by a toothed part of the piston.
16. (canceled)
17. The device as claimed in claim 1, wherein the piston is secured to the arm and wherein, the arm being mounted on and demounted from an element secured to the windshield wiper, the piston is movable between an unlocked position, in which unlocking is authorized, and a locked position, in which the piston forms a stop preventing demounting.
18. The device as claimed in claim 11, wherein the arm is mounted or demounted from the element secured to the windshield wiper with the aid of a clip the clip comprising a lug mounted on a removable platform, and wherein the platform is provided with a housing to receive the piston placed under the lug, so that the piston forms a stop for the platform when engaged in said housing in the locked position.
19. The device as claimed in claim 11, wherein the element secured to the windshield wiper is an adapter.
20. The device as claimed in claim 1, wherein said at least one locking element comprises a bimetal strip.
21. The device as claimed in claim 14, wherein the bimetal strip is deformable by a variation of temperature from a locked position in which it is secured to an end part of the arm and an adapter to an unlocked position in which it is secured only to the end part.
22. The device as claimed in claim 14, wherein the electrical means are adapted to heat the bimetal strip.
23. (canceled)
24. A windshield wiper, comprising a locking device as claimed in claim 1.
25. A motor vehicle, comprising a windshield wiper; a drive arm; a device for locking the wiper to the arm as claimed in claim 1; means for activation of the locking; and means for detection of the presence of a driver in the vehicle and/or the operation of an ignition switch in the vehicle, the activation means being able to activate the locking in the event of detection by the detection means of the presence of a driver in the vehicle and/or of starting of the engine of the vehicle.
26.-29. (canceled)
Description
[0040] The invention will be better understood and other details, features and advantages of the invention will become apparent on reading the following description given by way of nonlimiting example and with reference to the appended drawings in which:
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[0070] In the following description, the terms longitudinal and lateral refer to the orientation of the windshield wiper according to the invention. The longitudinal direction corresponds to the principal axis of the wiper along which it extends, while the lateral orientations correspond to straight line segments that are concurrent, i.e. that cross the longitudinal direction, in particular perpendicular to the longitudinal axis of the wiper in its rotation plane. For the longitudinal directions, the terms exterior and interior are understood relative to the point at which the wiper is fixed to a wiper arm, the term interior corresponding to the part where the arm and a half-wiper extend. Finally, the directions referred to as upper and lower correspond to orientations perpendicular to the rotation plane of the windshield wiper, the term lower containing the plane of the windshield.
[0071] Referring to
[0072] There is shown in
[0073] Here the wiper 10 comprises a longitudinal cover member 14, a longitudinal wiper blade 16, generally of rubber, and at least one longitudinal spine 18 that stiffens the blade 16 in such a manner as to strengthen the application of that blade 16 to the windshield.
[0074] The cover member 14 of the wiper 10 includes an upper aerodynamic deflector 20 intended to improve the operation of the windshield wiper, the purpose of this deflector 20 being to strengthen the pressing of the wiper 10 onto the windshield and therefore to improve the overall aerodynamic performance.
[0075] The wiper 10 further comprises end-pieces or clips 22 for attaching the blade 16 and the spine 18 to the cover member 14, these clips 22 being situated at each of the longitudinal ends of the cover member 14.
[0076] Here the cover member 14 of the wiper is made in two independent parts that are disposed substantially end-to-end and separated from one another by an intermediate connector 24. This connector 24 is therefore inserted between the two parts of the cover member 14 and may comprise fluidic connection means of means for feeding windshield washer liquid from the connector 24 to pipes of the member 14.
[0077] For mounting it on the arm 12, the wiper 10 comprises an adapter 26 mounted on the connector 24 and allowing articulation of the wiper 10 relative to the arm 12. The articulation of the wiper 10 relative to the arm 12 is an articulation in accordance with a movement of rotation about a rotation axis Y perpendicular to the longitudinal axis of the wiper 10. The wiper 10 must in fact have at least one degree of freedom in rotation relative to the arm 12, and to be more specific relative to an end part 28 of the arm 12, to allow the wiper 10 to follow the curvature of the windshield.
[0078] Modern wipers being costly, it is desirable to prevent the theft of these wipers, in particular by locking the arm 12 to the wiper 10 in an immobilization zone I with a retention force G that is typically greater than 100 N (
[0079] The invention enables this objective to be achieved, by using electrical means able to drive a reversible movement of at least one locking element between a so-called unlocked position in which said at least one element no longer locks the wiper to the arm and a so-called locked position in which said at least one element locks the wiper to the arm.
[0080] An electromagnetic field may be used to lock the wiper to the arm, in particular with the aid of an electromagnet, which is a member producing a magnetic field when it is supplied with electricity. The theory underlying this first embodiment is shown in
[0081] A current generator 1, such as a battery, feeds a solenoid 2 with electrical current. A solenoid is a device constituted of an electrical wire wound regularly in a helix in such a manner as to form a long coil. Carrying a current, it produces a magnetic field B in its vicinity, and more particularly inside the helix, where this field is virtually uniform. The magnetic field lines drive the movement of a core 3 disposed in the interior of the coil 2. Thus, from a first end position of the core 3 (
[0082] Accordingly, in a first embodiment, these two end positions of the core are used to define a locked position and an unlocked position of the arm and the wiper. In particular, the first end position defines an unlocked position of the arm and of the wiper and the second end position defines a locked position of the arm and of the wiper.
[0083] Four examples conforming to this first embodiment are described next. In these examples, the core 3 serves as a piston.
[0084] In a first example, the wiper is locked to the arm with the aid of two locking rods 5 secured to a member of the wiper for example of the connector 24, and substantially orthogonal to the core 3 of the electromagnet 4. The rods 5 are movable in translation with the aid of the core 3 between an unlocked position of the device and a locked position of the device in which the rods 5 each come to obstruct an opening 6 of the end part 28 of the arm, said end part 28 commonly being termed a yoke. In this example, the electromagnet 4 may be secured to the arm.
[0085] In an unlocked position, shown in
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[0087] In this first example, the device enables securing (locking) of the arm to the wiper in the locked position and rotation of the wiper relative to the arm, for example about the axis Y in
[0088] In a second example, there is used instead of the rods 5 a leaf spring 9 secured to a member of the wiper, for example the connector 24, that exerts a return force longitudinally relative to the electromagnet 4 and its core 3. The leaf spring 9 is disposed substantially orthogonally to the core 3. In an unlocked position, shown in
[0089] The movement of the core 3 to its second end position will drive the actuator 13 in translation, which will deform the spring 9 into a deployed position in which the spring 9 is substantially straight and in which the ends 9a of the spring 9 are engaged in the openings 6 of the yoke 28 (
[0090] In this second example, the device enables securing (locking) of the arm to the wiper in the locked position and rotation of the wiper relative to the arm, for example about the axis Y in
[0091] In a third example, the core 3 comprises a crenelated (toothed) end 32 meshing with a toothed shaft 17. The toothed shaft 17 passes through two elongate openings 6, for example of rectangular section, of the yoke 28 and comprises two elongate ends 17a each projecting from an opening 6.
[0092] In the unlocked position shown in
[0093] The movement of the core 3 to its second end position will drive the toothed shaft 17 in rotation to the locked position (
[0094] The meshing is preferably configured so that the passage of the core 3 from its first end position to its second end position drives a rotation of approximately 90 of the toothed shaft 17.
[0095] In this third example the device enables securing (locking) of the arm to the wiper in the locked position and rotation of the wiper relative to the arm, for example about the axis Y in
[0096] In a variant of the first embodiment, the electromagnet 4 is replaced by an electromechanical card 4. The electromechanical card 4 enables the piston 3 to be moved by an electric current.
[0097] By analogy with
[0098] The three examples conforming to this embodiment are shown in
[0099] In a fourth example of this first embodiment, it is the piston 3 itself that constitutes the locking element. In the unlocked position shown in
[0100] Alternatively, the electromagnet 4 may be replaced by an electromechanical card, as described above.
[0101] In this fourth example, the device enables securing (locking) of the arm to the wiper in the locked position.
[0102] In a second embodiment of the locking device according to the invention, the locking element is a bimetal strip. A bimetal strip is a component comprising two strips of different metals or alloys with different thermal expansions. The expansion of the two strips being different, the bimetal strip is deformed with variations of temperature. The strips, generally flexible, are welded, for example by cold rolling, or glued one against the other, in the lengthwise direction.
[0103] This principle is shown in
[0104] The deformations and the forces developed can be calculated from parameters of each component and the temperature variation. The deviation of the bimetal element is given by the following equation:
[0105] in which: [0106] designates the deviation of the bimetal element (m), [0107] V designates the specific curvature (K.sup.1), [0108] L designates the length of the bimetal element (m), [0109] T designates the temperature variation (K), [0110] e designates the thickness of the bimetal element (m).
[0111] The specific curvature is given by the equation:
[0112] in which: [0113] V designates the specific curvature (K.sup.1) [0114] E.sub.1 and E.sub.2 designate the moduli of elasticity of the respective materials in the temperature range (Pa), [0115] .sub.1 and .sub.2 designate the respective coefficients of thermal expansion of the materials (K.sup.1). [0116] e=e.sub.1+e.sub.2 designates the thickness of the bimetal element (m), [0117] e.sub.1 and e.sub.2 designate the thickness of the respective materials (m).
[0118] If E.sub.1.e.sub.1.sup.2E.sub.2.e.sub.2.sup.2=0, the maximum value of V is reached, with the result that:
[0119] This ratio enables deduction of the optimum dimensions of the bimetal element and the materials used to obtain the maximum deviations and forces.
[0120] In this case, the materials must be chosen according to: [0121] their use in micro-fabrication, [0122] their electrical conductivity, so as to be heated by the Joule effect, [0123] their greater coefficient of thermal expansion.
[0124] Actually, the optimum ratio of the thickness of the materials for maximum force and maximum deviation is obtained from the Young's modulus of each material. Taking by way of example as materials aluminum, which is the most used material in micro-fabrication, and silicon, with respect to which aluminum has the greatest difference in terms of coefficient of thermal expansion:
[0125] The thickness of the bimetal element can therefore be determined.
[0126] In the unlocked position, the bimetal strip may be secured to the arm of the windshield wiper. As shown in
[0127] One end of the bimetal strip 19 may be in thermal contact with a heating part 27, for example a heating element, which may be disposed on the support 28a of the yoke 28. In the locked position shown in
[0128] Alternatively, as shown in
[0129] In this second embodiment, the device enables securing (locking) of the arm to the wiper in the locked position.
[0130] In a third embodiment, locking is produced with the aid of magnetization means secured to the arm or to the wiper and cooperating with means able to be magnetized and secured to the wiper or to the arm, respectively, and the magnetization means or the means able to be magnetized are rotatably mounted in the arm or the wiper to which they are secured. This embodiment is shown in
[0131] The locking device may therefore comprise an electromagnet 30 secured to the connector 24 and intended to magnetize a metal part 33 that is rotatably mounted in the adapter 26 with the aid of a rotation shaft 33a. The adapter 26 is secured to the yoke 28 of the arm 12 (
[0132] The locking device may therefore be mounted vertically to obtain the configuration from
[0133] Alternatively, as shown in
[0134] In this third embodiment, the device enables securing (locking) of the arm to the wiper in the locked position and rotation of the wiper relative to the arm, for example about the axis Y in