DE102013111460A1 - Method for obtaining electrical energy in motor vehicles and apparatus therefor - Google Patents

Abstract

The invention relates to a method for obtaining electrical energy in motor vehicles, wherein at least one piezoelectric element 7, 8 is arranged in the region of the connection of components 1 to body parts 2 or 2 in the vehicle such that upon the occurrence of vibrations and / or vibrations of the component 2 against the carrier or the body 1 pressure on the at least one piezoelectric element 7, 8 is applied.

Description

The invention relates to a method for obtaining electrical energy in motor vehicles and a device therefor.

Motor vehicles are operating systems with a myriad of registered vibrations, either by the operation of an internal combustion engine, or by vibration input while driving.

It is therefore necessary in vehicles to ensure that the registered vibrations do not cause the entire complex of components in motor vehicles to stimulate natural oscillations to dampen or eliminate these natural oscillations.

A plurality of parts in automobiles are therefore attached to a support or to a body of a motor vehicle with decoupling elements. Such decoupling elements consist of several components, comprising at least one unit for fixing the component to the carrier, such as in particular screws, rivets, clamps, clips, etc., and a damping element which decouples the fixing unit from the component, d. H. between the component and the carrier or the component and the fixing unit or the fixing unit and the carrier is arranged so that a vibration decoupling takes place. In the simplest case, for example with motor carriers, these are rubber buffers. After the fuser generally acts on both sides of the component to be fastened, two separate damping elements are usually mounted on the top and bottom of the components.

In addition, it is known to influence the natural vibrations of components or the resonant vibrations of components by applying heavy layers selectively or over a wide area.

Both decoupling elements and correspondingly coated components thus dampen transmitted vibrations due solely to inertia.

The object of the invention is to provide a method for gaining energy and for influencing vibration and vibration states.

The object is achieved by a method having the features of claim 1.

Further developments are characterized in subclaims.

It is also an object to provide a device for carrying out the method.

The object is achieved with a device having the features of claim 8. Advantageous developments are characterized in the dependent claims.

According to the invention, the decoupling elements are designed to be piezo-active, which means that piezoelectric transducers are integrated in the decoupling elements. For this purpose, for example, piezoactive thin films can be integrated into the composite of the decoupling element overall unit. In particular, in this case, the layers can be integrated so that the damping action is not disturbed, on the other hand, however, sufficient pressure in the region of the piezoelectric elements is built up, so that electrical energy is released by the registered pressure. This makes it possible to tap the vibration or vibration energy in vehicles to the decoupling elements and to provide the vehicle electrical system. As a result of the large number of suspensions or decoupling points, a considerable proportion of energy can thereby be correspondingly converted.

For this purpose, the piezoelectric transducer between the component and damping element but also between the damping element and fixing unit can be attached.

If piezoactive elements with sufficient internal damping are available, they can completely replace classical damping elements from the decoupling elements, so that the fastening consists exclusively of a fixing element and a piezoactive unit.

For this purpose, the piezo-active elements can, of course, be mounted on both sides of a component to be fastened analogously to a damping unit in such a way that the movements for the production of electrical energy can be utilized in the event of oscillations to the body and away from the body. It is preferred to completely replace classic decoupling elements with piezoactive decoupling elements. Advantageously, such piezoactive units can already be factory-installed in the fixing areas during the production of the component to be fastened.

In particular, it is possible to arrange piezo-active elements, for example in the form of perforated disks, in the production process of the components to be fastened in the region of receiving bores or holes for receiving a fixing unit in a circular disk around the holes on both sides.

It is particularly preferred in this case that a correct cable routing and the pre-assembly of connections is ensured because each piezoactive element requires two voltage connections.

Cables can be at least partially replaced by the metallic components themselves, especially in metallic components.

Another advantage of the invention is that the piezoactive decoupling elements in addition to the recovery of vibration energy can also contribute to the active vibration damping. For this purpose, a voltage profile can be specifically applied to the elements, which depends very strongly on specific boundary conditions of the system. This voltage profile, which can also be different in a system on different decoupling elements, accordingly generates a counter-excitation of the component to be fastened and thereby reduces, for example, effectively mechanical loads on the component or occurring vibrations or noises. Of course, this active decoupling can take place only temporarily, for example, when a component in certain load or driving conditions in the range of resonant vibrations (which should be traversed as quickly as possible in normal vehicle operation, especially in low speed ranges). As a result, for example, piezoelectric decoupling elements can supply energy during a large number of driving states and, in the case of certain driving states that bring the component close to the resonance frequency, excite the component via the attachment points in order subsequently to generate energy again.

In the invention it is advantageous that the invention provides a simple and cost-effective method to operate energy recovery on a variety of systems, largely independent of other boundary conditions. For the integration of the proposed piezoactive elements no unusual processes are needed, the integration into existing fasteners is possible in a simple manner. It is also advantageous that significant energy can be made available by the large number of decoupling points.

Furthermore, the piezoactive decoupling elements can at least temporarily be used for active vibration damping and in this way dampen mechanical loads or disturbing vibrations and / or noises.

The invention will be explained by way of example with reference to a drawing. It show here:

1 an embodiment of an inventive arrangement of piezoelectric elements in a decoupling device;

2 a further embodiment of the arrangement of piezoelectric elements in a decoupling device with a latching connection;

3 a further embodiment of an inventive arrangement of piezoelectric elements in the region of a stop damper.

To a flat component 1 on a body structure 2 To bind, it is known, attached to the body structure fixing 3 provided. The fixing device 3 owns one of the body structure 2 protruding shaft 4 in a region adjacent to the body structure a support plate 5 has. To the shaft 4 around and on the plate 5 resting is a first annular rubber damping element 6 arranged. Immediately the plate 5 opposite is on the rubber cushioning element 6 a circular disk-shaped first piezoelectric element 7 arranged. The piezoelectric element 7 is due to one of the body structure 2 to be decoupled component 1 flat, wherein the component 1 with a corresponding hole 18 around the shaft 4 is arranged around. On the component 1 the first piezoelectric element 7 diametrically opposite is a second piezoelectric element from the other side 8th also flat. Again on this piezoelectric element 8th is a second rubber damper 9 on, which also corresponds to the first rubber damper 6 is formed annular. Covering this upwards is a circular disk or washer 10 arranged, wherein the overall arrangement, for example, with a mother 11 , which on a threaded portion (not shown) of the shaft 4 is screwed on, is held.

Leads the component 1 now vibrations in relation to the body structure 2 off, the piezo elements become 7 . 8th alternately pressurized.

In a further advantageous embodiment ( 2 ) is a component 1 on a body structure 2 or other vehicle structure 2 arranged with a conventional snap or clips connection. This is in the body structure 2 a hole 12 present, which of a known clip 13 and its latching arms 14 having free end 15 can be accessed.

Here is a first circular disk-shaped piezoelectric element 7 (electrical connections not shown) flat on a component surface 16 on, wherein the circular-disk-shaped piezoelectric element is a hole or a bore 17 which has approximately the diameter of the bore 12 but in any case from the free end 15 of the clip 13 can be freely accessed.

Directly adjacent to the piezoelectric element is the component with its bore 18 with the holes 17 and 12 arranged in alignment. Also the diametrically opposite flat side of the component 1 is correspondingly the second piezoelectric element 8th arranged. On one of the component 1 opposite flat side of the second piezoelectric element 8th is the clip 13 with his lenticular clip head 19 so on that with the help of yourself at a bottom 20 the body structure supporting cog legs 14 and the Linsenkopf 19 of the clip 13 the component 1 via the first and second piezoelectric elements 7 . 8th at the structure 2 is held. Are now vibrations of the component 1 opposite the structure 2 or performed relative to this, the piezoelectric elements 7 . 8th alternately stressed to pressure.

Instead of a clip 13 is of course the arrangement with a screw or rivet or punched rivet o. Ä. Possible.

In this embodiment, in particular by further missing dampers via an active control of the piezoelectric elements 7 . 8th a vibration also in the component 1 be registered, for example, to attenuate the overall vibration by interference.

Moreover, in an advantageous embodiment (not shown) it is possible to use one of the piezoelectric elements 7 . 8th by a damper or z. B. to replace a compression spring.

In a further advantageous embodiment of the invention is between a component 1 and a body structure 2 , In particular, away from a connection or decoupling, a stop damper 21 , in particular, for example, a stop damper 21 made of an elastomeric material, provided. This stop damper 21 made of an elastomeric material may be in the range 22 a stop or impact of the component 1 also a hardened or more stable area 22 have. In the area of the stop damper 21 owns the component 1 between itself and the stop damper a piezoelectric element 23 which is due to vibrations or impacts of the device 1 on the stop damper 21 is pressurized. In particular, with the help of already described decoupling points can in this case a particular elastic component 1 in the area of the stop damper 21 be pressurized to influence vibrations, with the residual vibrations still pressure on the piezoelectric element 23 in such a way that the energy can be converted in this way.

In the invention it is advantageous that on the one hand occurring in vehicles vibration energy is not unused, but the vehicle is made available, and also with such inventive systems targeted vibrations can be introduced into components to influence, for example by interference, the overall vibration conditions so that harmful Vibrations or vibrations are reduced or reduced.

LIST OF REFERENCE NUMBERS

1

component

2

body structure

3

fixing

4

shaft

5

Support plate

6

Rubber damping element

7

piezoelectric element

8th

piezoelectric element

10

washer

11

mother

12

drilling

13

clip

14

support legs

15

free end

16

component surface

17

drilling

18

drilling

19

Pan head

20

bottom

21

stop damper

22

Area

23

piezoelectric element

Claims (10)

Method for obtaining electrical energy in motor vehicles, wherein in the area of the connection of components ( 1 ) to body parts ( 2 ) or carrier ( 2 ) in the motor vehicle at least one piezoelectric element ( 7 . 8th ) is arranged such that upon the occurrence of vibrations and / or vibrations of the component ( 2 ) relative to the carrier or the body ( 1 ) Pressure on the at least one piezoelectric element ( 7 . 8th ) is exercised. Method according to claim 1, characterized in that the piezoelectric element ( 7 . 8th ) between or in damping / decoupling elements ( 6 . 9 ) such as rubber dampers, plastic spacers and the like is arranged. Method according to one of the preceding claims, characterized in that by pressure on the piezoelectric element ( 7 . 8th ) is provided via lines of the vehicle electrical supply or an integrated unit for buffering / collecting the electrical energy obtained. Method according to one of the preceding claims, characterized in that the piezoelectric element ( 7 . 8th ) between component ( 1 ) and damping element ( 6 . 9 ) and / or between damping element ( 6 . 9 ) and a fixing unit ( 4 ) for fixing the component ( 2 ) on a body part ( 1 ) is arranged. Method according to one of the preceding claims, characterized in that a piezoelectric element ( 7 . 8th ) is used with sufficient internal damping, which in a conventional manner sufficient vibration decoupling between component ( 1 ) and body ( 2 ). A method according to claim 1, characterized in that the piezoelectric element with voltage or a voltage profile is applied such that it acts on the body to be arranged on the component with a predetermined vibration to dampen or eliminate interference or similar phenomena vibrations. Device for carrying out the method according to one of the preceding claims, characterized in that at least one piezoelectric element ( 7 . 8th ) at a decoupling device ( 6 . 9 ) between a structure ( 2 ) and a component ( 1 ), wherein the at least one piezoelectric element ( 7 . 8th ) with an area on a surface of the structure ( 2 ) bears directly or indirectly and with a further surface on a component ( 1 ) lies directly or indirectly, so that relative movements between the structure ( 2 ) and the component ( 1 ) Pressure on the piezoelectric element ( 7 . 8th ) exercise. Apparatus according to claim 7, characterized in that a fixing device ( 4 ) on the structure ( 2 ) or the component ( 1 ), wherein the fixing device ( 4 ) a shaft ( 4 ) and around the shaft ( 4 ) around a first damping element ( 6 ) is arranged on the first damping element, a piezoelectric element ( 7 ) is arranged, wherein the piezoelectric element ( 7 ) on a component to be decoupled from the structure ( 1 ) is applied directly or indirectly, the component ( 1 ) with a recess or bore ( 18 ) around the shaft ( 4 ) is arranged around. Device according to claim 7 or 8, characterized in that on the component ( 1 ) the first piezoelectric element ( 7 diametrically opposite a second piezoelectric element ( 8th ) is applied directly or indirectly, on this piezoelectric element ( 8th ) a second damping element ( 9 ) corresponding to the first damping element ( 6 ) annular around the shaft ( 4 ) is formed around, with a fastening device ( 11 ) is present, which the composite of damping elements ( 6 . 9 ) and piezo elements ( 7 . 8th ) as well as component ( 1 ) and fixing device ( 4 ) holds together. Device according to one of the preceding claims, characterized in that the fixing device is a screw bolt, a clip, a rivet, a punch rivet or the like.

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