WO2010025979A1

WO2010025979A1 - Generator module and method for producing a generator module

Info

Publication number: WO2010025979A1
Application number: PCT/EP2009/058796
Authority: WO
Inventors: Franz Laermer; Thorsten Pannek; Ralf Reichenbach; Marian Keck
Original assignee: Robert Bosch Gmbh
Priority date: 2008-09-05
Filing date: 2009-07-10
Publication date: 2010-03-11
Also published as: DE102008041852A1

Abstract

The invention relates to a generator module (1) comprising a seismic mass (2), a piezoelectric element (3), an electrode (10) and a housing (4). The seismic mass and the piezoelectric element are situated inside the housing and the piezoelectric element is connected to the electrode in an electrically conductive manner. At least part of the electrode is situated outside the housing.

Description

description

title

Generator module and method for producing a generator module

State of the art

The invention is based on a generator module according to the preamble of claim 1.

Such generator modules are well known. For example, the publication DE 10 2007 006 994 A1 discloses a circuit module with a housing and a piezoelectric generator, which has a mass element movable within the housing and a spring device comprising at least one piezoelectric element, wherein the mass element and the spring device form an oscillatable system and the piezoelectric element is elastically deformable in the vibration of the oscillatory system, and wherein the circuit module has a power supply circuit for receiving a piezo voltage output from the piezoelectric element in its mechanical deformation and powering the circuit module.

Disclosure of the invention

The generator module according to the invention and the inventive method for producing a generator module according to the independent claims have the advantage over the prior art that the piezoelectric element can be contacted from outside the housing via the electrode. This is achieved in that the electrode is partially disposed outside of the housing. In particular, only the oscillatory system of piezoelectric element and seismic mass are arranged in the interior of the housing, wherein a bending of the piezoelectric element due to a deflection or acceleration of the seismic mass generates a piezoelectric voltage which over the electrode is led out of the housing and therefore can be tapped off from outside the housing. Thus, an arrangement of further electrical or electronic components within the housing is not particularly advantageous and the generator module is significantly space-compact executable. Furthermore, the generator module can be modularly integrated into a wide variety of electrical circuits, wherein the generator module is preferably fastened and contacted directly on printed circuit boards. The generator module is preferably used as a vibration generator or energy supply unit, in particular for tire pressure monitoring systems.

Advantageous embodiments and modifications of the invention are the dependent claims, as well as the description with reference to the drawings.

According to a preferred embodiment, it is provided that the generator module has a further electrode, wherein the further electrode is electrically conductively connected to the piezoelectric element and wherein the further electrode is at least partially disposed outside of the housing. Thus, a first side of the piezoelectric element with the electrode and a second side of the piezoelectric element with the further electrode are both electrically conductive, and preferably mechanically connected, so that the piezoelectric voltage resulting from the bending of the piezoelectric element between the electrode and the further electrode abuts and in particular differentially out of the housing via the electrode and the further electrode.

According to a further preferred development, it is provided that the electrode has at least one bend outside the housing and / or the further electrode outside the housing has at least one further bend, the electrode preferably being formed by the bend and / or the further electrode due to the further bending a base side of the housing is guided, so that in particular the electrode and / or the further electrode form contact surfaces on the base side. Thus, a particularly advantageous mounting, in particular by a soldering process, the generator module as an SMD module (Surface Mounted Device) directly on a circuit board allows. Particularly preferably, an automatic assembly of a printed circuit board with the generator module in an SMT process (Surface Mounted Technology) can be realized.

According to a further preferred embodiment, it is provided that the electrode and / or the further electrode are fastened to the housing outside of the housing by means of a fastening element, so that undesired further bending of the electrode and / or the further electrode outside the housing is particularly advantageously prevented.

According to a further preferred embodiment, it is provided that the housing comprises a housing cover, wherein in a transition region between the housing cover and the rest of the housing preferably sealing means and / or adhesives are arranged, so that particularly advantageously the housing is hermetically sealed and thus against interference, such as For example, changing external pressure, moisture, dirt or oil is protected.

According to a further preferred development, it is provided that the electrode comprises a first part and a second part and / or the further electrode comprises a further first part and a further second part, wherein preferably the first part and / or the further first part in the rest of the housing and the second part and / or the further second part is arranged at least partially in the housing cover, and wherein the second part particularly preferably comprises a contact surface and / or the further second part comprises a further contact surface respectively on an outer side of the housing cover. Thus, the contact surfaces are particularly advantageously formed by the second part and / or the further second part, so that the contact surface to be arranged before closing the housing to the rest of the housing or on the housing cover and / or the rest of the housing or the housing cover before the closing of the housing on the circuit board is electrically contacted and fixed. Furthermore, thus is a

Bending method for bending the electrode and / or the further electrode for generating the contact surfaces on the base can be saved. According to a further preferred embodiment, it is provided that the generator module has a holding element, wherein the holding element is preferably formed substantially bar-shaped and particularly preferably at the end points of the support member anchoring elements for suspending the support member on the housing and in particular on the housing cover. Particularly advantageously, the support member is attached via the anchor elements to the housing, wherein the anchor elements are particularly preferably clamped between the remaining housing and the housing cover, so that when closing the housing particularly advantageous at the same time the support member is attached.

According to a further preferred refinement, provision is made for the seismic mass to be arranged on a first side of the holding element and for the piezoelectric element to be arranged on a second side of the holding element, in particular in each case substantially centrally between the two end points. Advantageously, via the holder element, which preferably comprises an elastically deformable material and more preferably a metal sheet, the seismic mass is movably mounted relative to the housing on the housing, wherein the piezoelectric element preferably on the second side of the support member and therefore opposite to the seismic mass of the support element is arranged. Particularly advantageously, movement of the seismic mass relative to the housing produces bending of the support member in the center of the support member, i. substantially centrally between the anchor elements, so that the deflection of the support member transmits directly to the piezoelectric element and thus a piezoelectric voltage between the electrode and the further electrode is generated.

According to a further preferred embodiment, it is provided that the housing has a recess for leading out the first electrode out of the housing and / or a further recess for guiding out the second electrode out of the housing, the recess and / or further recess preferably in the transition area and / or is arranged in the housing cover. Thus, it is particularly advantageous to lead out the electrode and / or the further electrode in the region of the remaining housing, in the region of the housing cover and / or in the transition region possible, wherein a lead out of the electrode and / or the further electrode by a recess in the transition region, which in particular comprises a recess in the housing wall of the housing from the transition region, advantageously simplifies the manufacturing process of the generator module, since a comparatively complex

Manufacturing step for threading the electrode and / or the further electrode in a recess formed as a hole in the housing wall recess and / or further recess is eliminated.

According to a further preferred embodiment, it is provided that further sealing means and / or further adhesives are arranged between the recess and the first electrode and / or between the further recess and the further electrode, so that particularly advantageously the housing is hermetically sealed and thus against interference , such as changing external pressure, moisture, dirt or oil, is protected.

Another object of the present invention is a method for producing a generator module, wherein in a first manufacturing step, a seismic mass, a piezoelectric element, an electrode and preferably another electrode are arranged in a housing and in particular on a housing cover such that the electrode and Preferably, the further electrode are each at least partially disposed outside of the housing. In a particularly advantageous manner thus a generator module can be realized, wherein the piezoelectric element from outside the housing is directly or indirectly contacted. At the same time, the method according to the invention enables a comparatively efficient and cost-effective production process of this generator module, since the electrode and / or the further electrode are arranged in the housing in such a way that areas of the electrode and / or the further electrode are automatically outside the housing even after the housing has been closed are arranged. This is achieved by the fact that the electrodes and / or the further electrodes overlap the housings. The electrodes and / or the further electrodes are preferably arranged in the housing such that the electrodes and / or the further electrodes partially in recesses and / or in other recesses in the housing wall arranged and in particular inserted or inserted, wherein the recesses and / or further recesses are preferably each as holes in the housing wall and / or as emanating from the transition region recess in the housing wall. Particularly preferably, it is provided that, in a further production step, the electrode and / or the further electrode is coated with a comparatively easily solderable material, in particular in the area outside the housing. Alternatively, the material of the electrode and / or the further electrode particularly preferably comprises a comparatively easily solderable material, so that an electrically conductive solder contact on the electrode and / or the further electrode, in particular with a printed circuit board outside the housing, can be produced particularly easily.

According to a preferred development, it is provided that the first production step comprises a first partial step, wherein the housing is closed by attaching the housing cover to the rest of the housing, a second partial step, wherein the electrode passes through a recess and / or the further electrode through a further recess led out of the housing, and / or a third sub-step, wherein a first part of the electrode with a second part of the electrode and / or a further first part of the further electrode is connected to a further second part of the further electrode comprises. Advantageously, the housing is thus hermetically sealed in the first production step with comparatively few partial steps, and the electrode and / or the further electrode led out of the housing. The preparation of a connection between, for example, a first and a second part of the electrode in the third sub-step particularly advantageously allows a separate

Assembly of the first part of the electrode, for example in the rest of the housing and the second part of the electrode, which is integrated in particular by means of an insert in the housing cover, wherein the second part comprises contact surfaces on the outside of the housing cover, preferably for an SMT process.

According to a further preferred development, it is provided that, in a second production step, the electrode and / or the further electrode outside the housing, in particular on a base surface of the housing, is bent. It is advantageous by the bending process in comparatively simple and cost-effective, the formation of a contact surface or a further contact surface in particular parallel to the base surface of the housing feasible, so that an assembly of a circuit board with the generator module is made possible in an SMT process.

According to a further preferred embodiment, it is provided that in a third manufacturing step, the piezoelectric element is mounted on a support member, wherein the first sub-step preferably includes a pinching of the support member or of anchor elements of the support member between the housing cover and the rest of the housing. Advantageously, both the housing is hermetically sealed at the same time in the first sub-step, as well as the support member fixed together with the piezoelectric element and the seismic mass to the housing by clamping. For attachment and sealing thus only a single manufacturing step is necessary.

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

Brief description of the drawings

Show it

Figure 1 is a schematic perspective view of a section through a

Generator module according to a first embodiment of the present invention,

FIG. 2 shows a schematic and perspective partial view of a generator module according to the first embodiment of the present invention,

FIG. 3 shows a schematic side view of a generator module according to a second embodiment of the present invention,

Figure 4 is a schematic side view of a generator module according to a third embodiment of the present invention and Figure 5 is a schematic side view of a generator module according to a fourth embodiment of the present invention. Embodiments of the present invention

In the figures, the same parts are always provided with the same reference numerals and are therefore usually named only once in each case.

FIG. 1 shows a schematic perspective view of a section 100 through a generator module 1 according to a first embodiment of the present invention, wherein the generator module 1 comprises a seismic mass 2, a piezoelectric element 3, a holding element 5, an electrode 10, a further electrode 20 and a housing 4, wherein the support member 5 is bar-shaped and has at its end points 5 'anchoring elements 5 "for suspending the support member 5 on the housing 4. Essentially midway between the end points 5' on a first side 50 of the support member 5 is the The support element 5 preferably comprises an elastically deformable material, in particular a metal sheet, so that the seismic mass 2 is movably suspended relative to the housing 4 and an acceleration or deflection of the seismic mass 2 relative to the housing 4 causes a reversible deformation of the seismic mass 2 Halterungsele ment 5 causes. On one of the first side 50 opposite second sides 51 of the support member 5 is in particular substantially centrally between the end points 5 ', the piezoelectric element 3 is fixed, in particular glued, soldered or bonded, so that the deformation of the support member 5 is a bending of the piezoelectric element causes and between a first and a second contact surface of the piezoelectric element 3, a piezoelectric voltage is generated. The electrode 10 is mechanically and electrically conductively connected to the first contact surface and the electrode 20 to the second contact surface, so that the piezoelectric voltage via the electrode 10 and / or further electrode 20 from outside the housing 4 can be tapped. The first contact surface is preferably the upper side and the second contact surface is the underside of the piezoelectric element 3. The housing 4 comprises a

Housing cover 4 'and a remaining housing 4 ", wherein the anchor elements 5" are clamped in a transition region 40 between the housing cover 4' and the rest of the housing 4 " Recess 25 led out of the housing 4, so the electrode 10 and the further electrode 20 can be contacted outside the housing 4. In the recess 15 and the further recess 25 further adhesive and / or sealing means are preferably arranged, so that the housing 4 'is hermetically sealed. Preferably, the electrode 10 or the further electrode 20 at least outside the housing 4, a coating with a comparatively good solderable material. Between the housing cover 4 'and the remaining housing 4 ", an adhesive and / or sealing means is preferably arranged in the transition region 40, so that the housing 4 is hermetically sealed and the housing cover 4' is materially connected to the rest of the housing 4 is a positive and / or non-positive connection between the housing cover 4 'and the remaining housing 4 "is provided. The housing cover 4 'is in particular glued, pressed, welded, clamped, screwed and / or fastened by means of clips with the rest of the housing 4 ".

To produce the generator module 1 according to the first embodiment of the present invention, for example, first the electrode 10 and the further electrode 20 are arranged on the top and bottom of the piezoelectric element 3, preferably then the seismic mass 2 and the piezoelectric element 3 together with the Electrode 10 and the other electrode 20 is fixed to the support member 5 and in a subsequent step, the support member 5 is arranged together with the seismic mass 2, the piezoelectric element 3, the electrode 10 and the further electrode 20 on the housing cover 4 ', wherein the electrode 10 and the further electrode 20 overlap the housing cover 3 'in such a way that, when the housing 4 is closed, regions of the electrode 10 and the further electrode 20 are arranged outside the housing 4. For this purpose, the electrode 10 and the further electrode 20 are particularly preferably inserted or inserted into a recess 15 and a further recess 25. The recess 15 and the further recess 25 very particularly preferably comprise outgoing U-shaped recesses in the transition area 40

Housing wall of the housing 4 or alternatively holes in the housing wall of the housing. In a subsequent step, the rest of the housing 4 "on the housing cover 4 'is arranged and thus the support member 5 between the housing cover 4' and the remaining housing 4" clamped, the rest Housing 4 "with the housing cover 4 'material, force and / or positively connected and wherein between the housing cover 4' and the rest of the housing 4" preferably an adhesive and / or sealing means for hermetically sealing the housing 4 is introduced. In subsequent steps, the electrode 10 and the further electrode 20 outside the housing 4 are preferably coated and the generator module 1 arranged on a non-illustrated circuit board and / or the electrode 10 and the further electrode 20 electrically conductively contacted outside of the housing 4. On the electrode 10 or the further electrode 20 outside of the housing 4, an easily solderable material is particularly preferably applied in an intermediate step, for example in the form of sputtered or galvanically grown layers and / or in the form of so-called "bumps" or "solder balls", which are applied in particular by means of pick-and-place method and then melted.

FIG. 2 shows a schematic and perspective partial view 1 'of a

Generator module 1 according to the first embodiment of the present invention shown, wherein the partial view V shown in Figure 2 is identical to the generator module 1 shown in Figure 1, wherein only the housing cover 4 ', the seismic mass 2, the piezoelectric element 3, the support member 3, the electrode 10 and the further electrode 20 are shown and, for reasons of clarity, only the rest of the housing 4 "is not shown, the sectional view of Figure 1 corresponds to a section through the partial view V according to the line 100.

Shown in Figure 3 is a schematic side view of a generator module 1 according to a second embodiment of the present invention, wherein the second embodiment is substantially identical to the first embodiment shown in Figures 1 and 2, wherein the side view only the housing 4 with housing cover 4 'and the rest Housing 4 ", as well as the areas of the electrode 10 and the further electrode 20 outside the housing 4 represents.

FIG. 4 shows a schematic side view of a generator module 1 according to a third embodiment of the present invention, the third embodiment being identical to the second embodiment illustrated in FIG. 3, wherein the electrode 10 and the further electrode 20 have each twice outside of the housing 4, in particular in a trim-and-molding process, bent along the outside of the housing 4, so that on a base side 6 of the housing 4, a contact surface 14 of the electrode 10th and a further contact surface 24 of the further electrode 20 is formed. The generator module 1 can thus be soldered or bonded as an SMD component in an SMT process, for example directly to a printed circuit board not shown. Alternatively, the generator module 1 is mechanically clamped on a circuit board and contacted or connected to a non-illustrated circuit board by a bonding process with a conductive adhesive.

FIG. 5 shows a schematic side view of a generator module 1 according to a fourth embodiment of the present invention, the fourth embodiment being substantially similar to the third embodiment illustrated in FIG. 4, the electrode 10 having a first and a second part 12, 13 and the others Electrodes 20 comprises a further first and a further second part 22, 23. Preferably, the second and further second part 13, 23 are formed as an insert in the housing cover 4 '. In the production of the generator module 1, preferably the insert part is arranged in the housing cover 4 'and particularly preferably the support element 5 together with the seismic mass 2, the piezoelectric element 3, the first part 12 of the electrode 10 and the further first part 22 of the further electrode 20 arranged in the housing cover 4 '. Subsequently, the first part 12 is electrically conductively connected to the second part 13 in a contact 18, so that the first and the second part 12, 13 together form the electrode 10. Similarly, the further first part 22 is electrically conductively connected to the further second part 23 in a further contact 28, so that the further first and the further second part 22, 23 together form the further electrode 20. The contact 18 and the further contact 28 are produced in particular by soldering, welding or gluing. Alternatively, the first and further first part 12, 22 in the remaining housing 4 "is arranged and connected directly mechanically and electrically conductive with the top and bottom of the piezoelectric element 3, wherein the second and further second part 13, 23 as an insert in the housing cover 4 'are formed and comprise a contact surface 14 and a further contact surface 24 on the base side 6 of the housing cover 4' second part 3 are arranged in this case, for example, such that when closing the housing 4, ie when assembling the housing cover 4 'and other housing 4 ", the first and the second part 12, 13 come into contact and forms an electrically conductive contact 18 so that the first and second parts 12, 13 together form the electrode 10. Analogously, the further first and further second parts 22, 23 come into contact and form an electrically conductive further contact 28 and thus the further electrode 10.

Claims

Patent claims

1. Generator module (1) with a seismic mass (2), a piezoelectric element (3), an electrode (10) and a housing (4), the seismic mass (2) and the piezoelectric element (3) within the

Housing (4) are arranged and wherein the piezoelectric element (3) is electrically conductively connected to the electrode (10), characterized in that the electrode (10) is at least partially arranged outside the housing (4).

2. Generator module (1) according to claim 1, characterized in that the generator module (1) has a further electrode (20), wherein the further electrode (20) is electrically conductively connected to the piezoelectric element (3) and wherein the further electrode (20) is at least partially arranged outside the housing (4).

3. Generator module (1) according to one of the preceding claims, characterized in that the electrode (10) outside the housing (4) has at least one bend (11) and / or the further electrode (20) outside the housing (4) at least one further bend (21), whereby the

Electrode (10) is guided through the bend (11) and/or the further electrode (20) through the further bend (21), preferably onto a base side (6) of the housing (4).

4. Generator module (1) according to one of the preceding claims, characterized in that the electrode (10) and / or the further electrode (20) are attached to the housing (4) outside the housing (4) by means of a fastening element.

5. Generator module (1) according to one of the preceding claims, characterized in that the housing (4) comprises a housing cover (4 '), wherein in a transition region (40) between the housing cover (4') and the remaining housing (4 " ) sealants and/or adhesives are preferably arranged.

6. Generator module (1) according to one of the preceding claims, characterized in that the electrode (10) has a first part (12) and a second part (13) and / or the further electrode (20) has a further first part (22). and a further second part (23), preferably the first part (12) and/or the further first part (22) in the remaining housing (4") and the second part (13) and/or the further second part ( 23) is at least partially arranged in the housing cover (4 ') and particularly preferably the second part (13) has a contact surface (14) and / or the further second part (23) has a further contact surface (24) each on an outside of the housing cover ( 4').

7. Generator module (1) according to one of the preceding claims, characterized in that the generator module (1) has a holding element (5), wherein the holding element (5) is preferably substantially bar-shaped and particularly preferably at the end points (5 '). of the holding element (5) has anchor elements (5") for suspending the holding element (5) on the housing (4) and in particular on the housing cover (4 ').

8. Generator module (1) according to one of the preceding claims, characterized in that on a first side (50) of the holding element (5) the seismic mass (2) and on a second side (51) of the holding element (5) the piezoelectric element (3), in particular each essentially centrally between the two end points (5 ').

9. Generator module (1) according to one of the preceding claims, characterized in that the housing (4) has a recess (15) for leading the first electrode (10) out of the housing (4) and / or a further recess (25) for leading the second electrode (20) out of the housing (4), the recess (15) and/or further recess (25) preferably being arranged in the transition region (40) and/or in the housing cover (4'). l O.Generator module (1) according to one of the preceding claims, characterized in that between the recess (15) and the first electrode

(10) and/or further sealing means and/or further adhesive means are arranged between the further recess (25) and the further electrode (20).

11.A method for producing a generator module (1), in particular according to one of the preceding claims, characterized in that in a first manufacturing step a seismic mass (2), a piezoelectric element (3), an electrode (10) and preferably a further electrode (20) can be arranged in a housing (4) and in particular on a housing cover (4 ') in such a way that the electrode (10) and preferably the further electrode (20) are each arranged at least partially outside the housing (4).

12. The method according to claim 11, characterized in that the first manufacturing step includes a first sub-step, wherein the housing (4) is closed by attaching the housing cover (4 ') to the remaining housing (4"), a second sub-step, wherein the electrode (10) through a recess (15) and/or the further electrode (20) through another

Recess (25) is led out of the housing (4), and / or a third sub-step, wherein a first part (12) of the electrode (10) with a second part (13) of the electrode (10) and / or a further first Part (22) of the further electrode (20) is connected to a further second part (23) of the further electrode (20).

13. The method according to one of claims 11 or 12, characterized in that in a second manufacturing step the electrode (10) and / or the further electrode (20) outside the housing (4), in particular on a base area of the housing (6), is bent.

14. The method according to any one of claims 11 to 13, characterized in that in a third manufacturing step the piezoelectric element (3) is attached to a holding element (5), the first sub-step preferably includes clamping the holding element (5) or anchor elements (5 ') of the holding element (5) between the housing cover (4') and the remaining housing (4").