Control element for manual input of control signals

Abstract

Control element for a motor vehicle with a rotatably mounted actuator, at least two signal-emitting permanent magnets (4, 5, 12, 13, 14) cooperating with the actuator and mounted diametrically on the actuator, a rotary angle detection device operating according to a magnetoelectric principle for detecting the angular positions and rotary movements of the actuator, and a downstream evaluation device, wherein for rotary angle detection the permanent magnets (4, 5, 12, 13, 14) are fixedly mounted on the actuator, wherein the field lines of the permanent magnets (4, 5, 12, 13, 14) are evaluated directly by means of a sensor (7) mounted stationary in the control element (1, 11) and evaluating field line directions, wherein the polarization of the permanent magnets (4, 5, 12, 13, 14) is different with respect to the sensor (7), characterized in that a stationary sensor, which is not oriented towards the permanent magnets (4, 5, 12, 13, 14) extending in the direction of the sensor (7),A metal grid (15, 16) consisting of one or more parts is attached between the sensor (7) and the permanent magnets (4, 5, 12, 13, 14), wherein the metal grid (15, 16) has a plurality of lamellae extending radially and radiating from the sensor (7) towards the permanent magnets (4, 5, 12, 13, 14), so that alignment and transmission of the field lines is possible.

Description

[0001] The invention relates to an operating element for a motor vehicle with a rotatably mounted actuator, a signal-generating permanent magnet cooperating with the actuator, a rotation angle detection device operating according to a magnetoelectric principle for detecting the angular positions and rotational movements of the actuator and a downstream evaluation unit.

[0002] A wide variety of evaluation methods are known for evaluating the rotary movements of an actuator in a control device in a motor vehicle. Examples of such evaluations include the adjustment of the volume of a radio receiver, the adjustment of a fan, the temperature of a seat heater, and similar functions. Since actuators in control devices in modern motor vehicles can often be assigned to adjust a wide variety of functions, evaluation devices based on an electrical principle are preferred for determining the angles and rotary movements of the actuators. This makes it possible to record the angular positions and rotary movements of the actuator alone, without being tied to fixed mechanical devices in the control element.

[0003] A generic operating device for the manual input of control signals to an evaluation unit is described in DE 199 06 535 A1. In this operating device, a rotary knob serves as a handle for an actuator. Specific angles of rotation of the actuator are assigned to individual functions of a menu, so that the corresponding menu item or function is selected by rotating the actuator. The actuator position is determined using an electromagnetic transducer. A transducer module operating according to a magnetoelectric principle is described, with a signal-generating permanent magnet assigned to the actuator. On the output side, the transducer module is connected to the input of a controller, such as a microprocessor.

[0004] An operating element according to the preamble of claim 1 is known from EP 1 009 972 B1. Operating elements of this type are also known from DE 102 12 953 A1, DE 10 2005 011 196 A1, DE 41 23 131 A1, EP 1 477 773 A1, and DE 40 14 885 A1.

[0005] Based on this prior art, the object of the invention is to develop an operating element for a motor vehicle that enables precise evaluation of the rotary movements and angular positions of an actuator, that is structurally simple, that is inexpensive to manufacture and that, moreover, allows buttons, light-guiding elements or elements to be positioned statically to be arranged inside the actuator of the operating device.

[0006] The object of the invention is achieved in that the permanent magnet is non-rotatably attached to the actuator for detecting the angle of rotation, wherein the field lines of the permanent magnet are directly evaluated by a sensor that is stationary and fastened in the control element and evaluates the field line directions. The inventive design of a control element, which is for example a rotary knob in an air conditioning control unit, now creates the possibility of providing a contactless system that precisely detects the angular positions and rotational movements of the actuator and provides them to a downstream or integrated circuit for evaluation. The permanent magnet attached to the actuator moves in a circle above the sensor that evaluates the field line directions and is fastened to a circuit board arranged in the control element.By attaching a permanent magnet or a permanent magnet ring to the actuator, it is possible according to the invention to design the actuator to be hollow and to attach, for example, a push button inside the actuator that can be actuated by a button located in the actuator, or, for example, a light-guiding element for backlighting the actuator.

[0007] According to the invention, at least two permanent magnets with different polarizations are attached to the actuator of the control element, each with a diameter and with different polarizations relative to the evaluating sensor. If the actuator is then rotated by an angle, the sensor evaluating the field line directions is able to detect this rotational movement and evaluate it in a downstream microprocessor, for example, based on predefined characteristic curves. Advantageously, the at least two permanent magnets are attached to an iron ring on the actuator. The permanent magnets are firmly connected to the iron ring by means of a positive or non-positive connection.

[0008] In a further embodiment of the invention, the integrated circuit for rotation evaluation, of which the sensor is a part, is fastened to the back, i.e. the side of a printed circuit board opposite the actuator. This achieves the inventive advantage that, for example, a button or a light source can be fastened centrally below the actuator on the circuit board. This is advantageous, for example, if the actuator is a rotary actuator with an integrated button. In this case, the button element on the circuit board can be actuated centrally using the button. However, a light source arranged on the circuit board can also be fastened centrally below the actuator on the circuit board for uniform illumination of the actuator or a rotary actuator.

[0009] A key element of the invention for improving the evaluation of the rotary movements of the actuator with integrated circuits for rotary evaluation arranged on the side opposite the actuator is the use of a fixed metal grid. According to the invention, the metal grid is manufactured as a stamped part from sheet metal. The metal grid amplifies the field lines generated by the permanent magnets in an antenna-like manner and directs them in the direction of the sensor. The invention provides for the metal grid to be formed from fixed rods that extend radially and radiately from the sensor towards the permanent magnets. In a preferred embodiment, the iron ring has an average diameter of 26 mm to which approximately 10 mm high permanent magnets are attached. In one embodiment, the metal grid has approximately 40 rods distributed uniformly around the circumference and widening radially outwards.Two diametrically arranged permanent magnets are attached to the rotating iron ring. The field lines of these permanent magnets penetrate the bars of the metal grid, which are also referred to as lamellae, located below each permanent magnet. These lamellae, the two diametrically opposite each other, transport the field lines to the integrated circuit containing the sensor for detecting the field line directions. It is practical and advantageous to match the size of the permanent magnets to the size of the lamellae of the metal grid, so that one permanent magnet roughly corresponds to the width of the lamellae on the outer circumference. For more precise analysis, the lamellae are spaced evenly around the circumference.

[0010] According to the invention, it is also conceivable not only to attach individual lamellae to the circumference, but also to arrange branching metal grids on the sensor, with the individual metal grids branching radially outward from the centrally located sensor and extending, for example, in a Y-shape outward below the permanent magnets. In this embodiment, it is expedient to attach a permanent magnet ring to the actuator. The permanent magnet consists of a metal ring with two poles, which is rotationally fixed to the actuator. The movement of the permanent magnet ring, which in turn is firmly connected to the iron ring, and the branching metal grids, in turn, enables a very precise evaluation of the rotary movements of the actuator.

[0011] The invention is explained in more detail below using exemplary embodiments and schematic diagrams. Fig. 1 a section through the lower part of an operating element equipped according to the invention in a side view, as well as detailed views, Fig. 2 a section through an operating part according to the invention with rotation angle detection according to the invention in a side view as well as detailed views and Fig. 3 another embodiment in side section with detailed views.

[0012] The three figures used for the description each show, in their upper image, a section through the lower part of an operating device 1 below the actuator in the area of ​​the circuit board 2. The iron ring 3 attached to the actuator carries the permanent magnets 4, 5, which in turn interact with the metal grid. The metal grids are angular and designed as separate slats 6 and extend from the lower end of the permanent magnets 4, 5 through the circuit board 2 to the integrated circuits provided with the sensor 7 for rotation evaluation. Components 9 can be attached to the interior 8 of the iron ring 3 and thus of the actuator between the permanent magnets 4, 5. These components can be used, for example, as a light source, light guide elements, buttons or similar for backlighting or illuminating or projecting the back of the actuator. The actuator and thus the iron ring 3 and the permanent magnets 4, 5 can be rotated in the direction of the arrow P.The one in the upper image of the . Fig. 1 The dimensions in mm indicate preferred sizes, which are not restrictive.

[0013] The middle image of the Fig. 1 shows a detailed view and in particular a top view of the iron ring 3 and the circuit board 2. The middle image shows the one-piece or two-piece iron ring 3 and the permanent magnets attached below the iron ring 3, which are attached diametrically on the iron ring 3. As in the upper image of the Fig. As can be seen in Figure 1, the permanent magnets 4, 5 are attached to the iron ring 3 in such a way that they exhibit different polarities in the direction of the lamellae 6. This different polarity can be evaluated via the sensor 7 and a microprocessor integrated into the integrated circuit with, for example, stored characteristic curves. The lower image of the Fig. 3 shows a view of the sensor 7 on the underside of the circuit board 2. As can be seen from the lower image, the dimensions of the permanent magnets 4, 5 correspond to the outer widths of the slats 6, so that a clear assignment of the field lines of the permanent magnets 4, 5 to the slats 6 can be established. In this exemplary embodiment, the slats 6 extend radially outwards from the sensor in a radially widening manner in the direction of the permanent magnets 4, 5. If the actuator is now moved in the direction of the arrow P, the iron ring 3 and the permanent magnets 4, 5 attached to the iron ring move over the ends of the slats 10. The field lines of the permanent magnets 4, 5 are guided through the ends 10 of the slats 6 to the sensor 7 and are available there for evaluation.The slats 6 enable the rotary movement of the actuator to be precisely evaluated, and the invention provides the advantage that, in addition to the contactless detection of the direction of rotation and the angle of rotation inside the actuator, components 9 can be applied to the circuit board 2.

[0014] The Fig. Figure 2 also shows a lateral section through the lower part of an operating element 11 according to the invention, wherein only the components essential to the invention are shown in their arrangement. Above the circuit board 2, a two-part permanent magnet ring 12 in the operating element 11 is rotatably attached and held on the actuator. It should be noted that, for the sake of clarity, identical components have been given the same reference numerals. The dimensions entered in the drawing indicate a preferred order of magnitude, which, however, is non-limiting and is essential to the invention. The required field strength at the surface of the integrated circuit 7 or at the sensor of the integrated circuit (sensor IC) is essential. The field lines must run horizontally through the sensor IC. The field strength required for this at the sensor IC surface is > 30 kA / m at a distance of < 2 mm.The operating temperature of the sensor is between -40°C and +85°C.

[0015] The one in the Fig. The permanent magnet 12 shown in Figure 2 consists of two halves 13, 14 that are differently polarized. Upon rotation of the actuator, and thus of the iron ring and the permanent magnet ring attached to the iron ring, the different polarization can be detected by means of the lamellae 6 of the metal grid 15.

[0016] A further, non-inventive embodiment of the invention is described in Fig. 3. In contrast to the embodiment of the Fig. 2, the metal grid 16 is not constructed from separate slats 6, but consists of branching bars 17. Starting from the center of the actuator, which is shown as a dot-dash line 18 in the figures, each bar extends radially outward and branches, forming the shape of a Y in plan view. At the radial ends 19 of the bars 17, the bars 17 are angled and extend through the circuit board 2 in the direction of the permanent magnets 13, 14. The distance between the ends 20 and the permanent magnets 13, 14 is essentially less than 2 mm. In the middle image of the Fig. 3, the angled radial ends 20 of the rods 17 are shown in dashed lines. It is, of course, understood that a branching of the rods 17 can have further branches depending on the required resolution and sensitivity. It is also conceivable to have not only three rods 17, as in Fig.3, but to use a larger number of branching bars 17.

Claims

[1] Operating element for a motor vehicle with a rotatably mounted actuator, at least two signal-generating permanent magnets (4, 5, 12, 13, 14) which interact with the actuator and are fastened diametrically to the actuator, a rotation angle detection device operating according to a magnetoelectric principle for detecting the angular positions and rotational movements of the actuator and a downstream evaluation device, wherein the permanent magnets (4, 5, 12, 13, 14) are fastened to the actuator in a rotationally fixed manner for detecting the rotation angle, wherein the field lines of the permanent magnets (4, 5, 12, 13, 14) are evaluated directly by means of a sensor (7) which is fixed in a stationary manner in the operating element (1, 11) and evaluates the field line directions, wherein the polarization of the permanent magnets (4, 5, 12, 13, 14) is different with respect to the sensor (7), characterized bythat a fixed metal grid (15, 16) of one-part or multi-part construction extending from the permanent magnets (4, 5, 12, 13, 14) in the direction of the sensor (7) is fastened between the sensor (7) and the permanent magnets (4, 5, 12, 13, 14), wherein the metal grid (15, 16) has a plurality of lamellae which extend radially and radiatingly from the sensor (7) in the direction of the permanent magnets (4, 5, 12, 13, 14), so that an alignment and transmission of the field lines is possible. [2] Control element according to claim 1, characterized by that the polarization of the at least two diametrically opposed permanent magnets (4, 5,12,13,14) is different with respect to the sensor (7). [3] Control element according to claim 1, characterized by that an iron ring (3) is attached to the actuator and the permanent magnets (4, 5, 12, 13, 14) are firmly connected to the iron ring (3). [4] Control element according to one of the preceding claims, characterized by that the sensor (7) is mounted on a circuit board (2), wherein the sensor (7) is mounted on a side of the circuit board (2) opposite the actuator. [5] Control element according to claim 1, characterized by that the metal grid (15, 16) is a stamped part. [6] Control element according to claims 3 and 4, characterized by that on the side of the circuit board (2) facing the actuator and within the iron ring (3) at least one button (9) and / or one lighting means (9) and / or one light-guiding element (9) and / or one element (9) for free programming of the actuator is fastened.

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