EP3386648A1

EP3386648A1 - Acoustic transducer arrangement having annular connecting regions and method for producing an acoustic transducer arrangement having annular connecting regions

Info

Publication number: EP3386648A1
Application number: EP16781792.3A
Authority: EP
Inventors: Bernd SCHEUFELE; Andre Gerlach
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2015-12-10
Filing date: 2016-10-14
Publication date: 2018-10-17
Also published as: DE102015224770A1; WO2017097474A1; CN108367316A

Abstract

An acoustic transducer arrangement (100) comprising: a perforated plate carrier (101) having a plurality of through-holes (111); a plurality of piezoelectric elements (104), each piezoelectric element (104) having a first electrode (105) and a second electrode (106), the first electrode (105) being opposite the second electrode (106) and a piezoelectric element (104) being provided within each through-hole (111); and a top layer (103), the top layer (103) being provided above the perforated plate carrier (101) and the piezoelectric elements (104), wherein the second electrodes (106) of the piezoelectric elements (104) are connected in an electrically conductive manner to the top layer (103), characterized in that the top layer (103) and the perforated plate carrier (101) have first connecting regions (108) which are situated concentrically around the through-holes (111), the first connecting regions (108) each having a larger diameter than the through-holes (111) and the first connecting regions (108) being annular.

Description

SOUNDWAVE ARRANGEMENT WITH RING-CONNECTED CONNECTION RANGES AND METHOD FOR PRODUCING AN SOUND CONVERTER ASSEMBLY WITH RING-FULLY CONNECTING RANGES

description

State of the art

The invention relates to a sound transducer assembly according to the preamble of claim 1 and a method for producing such

Transducer array.

Document DE 39 20 872 A1 discloses a method for the production of ultrasound layer transducers in which the piezoceramic and thermoplastic plastic material of the layer converter are connected to one another by heat bonding. To generate the heat necessary for bonding, heat loss is produced in the piezoceramic by applying electrical signals.

Document DE 10 2004 047 814 A1 describes a focusing micromachined ultrasound transducer array which is clinically focusing

usable ultrasonic probe can be used. Lateral side by side trained transducer cells are partially wired together electrically to the desired focus of the ultrasonic conversion to

to reach.

The disadvantage here is that the individual ultrasonic transducers external influences, both mechanical and electrical type, are exposed. Disclosure of the invention

The sound transducer arrangement comprises a perforated plate carrier with a plurality of through openings, a plurality of piezo elements and a terminating layer. Each piezoelectric element has a first electrode and a second electrode. The first electrode faces the second electrode. Within a passage opening, a piezoelectric element is arranged in each case. The

Finishing layer is disposed above the perforated plate carrier and the piezoelectric elements, wherein the second electrodes of the piezoelectric elements with the

End layer are electrically connected. According to the invention, the terminating layer and the perforated plate carrier have first connecting regions, which are arranged concentrically around the through-openings, the first connecting regions each having a larger diameter than the through-openings and the first connecting regions being of annular design.

The advantage here is that the edge clamping of the bending transducer elements is adjustable. In other words, certain vibrational mechanical

Properties of the bending transducer elements can be adjusted.

In a further development, the top layer and the hole plate carrier on second connection areas, which are arranged concentrically around the through holes. In this case, the second connection regions have a larger diameter than the first connection regions. The second

Connection areas are designed annular.

It is advantageous here that the individual bending transducer elements are decoupled from each other.

In a further embodiment, the first connection regions each have a weld seam. In other words, each first connection region comprises a weld seam. The advantage here is that the mechanical connection between the

Finishing layer and the perforated plate carrier is particularly stable and robust and has a high quality. In one development, the finishing layer is integrally formed.

The advantage here is that a composite of bending transducer elements is completely protected from external influences. In a further embodiment, the finishing layer has a plurality of sections, wherein in each case one section of the finishing layer is provided with one each

Piezoelectric element is electrically connected. In other words, the portion that is electrically connected to the piezoelectric element acts as a membrane of the bending transducer element.

The advantage here is that less material is needed.

In a development, the second connection areas have a

Weld on.

In a further embodiment, the top layer and the

Hole plate carrier on a third connection area. The third

Connecting region connects an edge region of the terminating layer with an edge region of the perforated plate carrier.

It is advantageous in this case that the third connection region as a seal of the entire sound transducer arrangement with respect to z. B. moisture and

Liquids acts. In a development, the third connection region has a weld seam.

The inventive method for producing a

Acoustic transducer assembly comprising a perforated plate carrier, a plurality

Through openings, a plurality of piezoelectric elements and a terminating layer comprises the connecting of second electrodes of the piezoelectric elements with the finishing layer. Furthermore, the method comprises contacting first electrodes of the piezoelements by means of wire bonding, wherein the first electrodes are arranged opposite to the second electrodes and the joining of the terminating layer and the perforated plate carrier by means of a weld. In addition, the method includes partially filling the through openings with a damping material.

The advantage here is that the transducer assembly can be cost-optimized and easily manufactured.

Further advantages will become apparent from the following description of

Embodiments or from the dependent claims.

Brief description of the drawings

The present invention will be described below with reference to preferred

Embodiments and attached drawings explained. Show it:

Figure la a first embodiment of an inventive

Transducer array,

Figure lb is a plan view of the invention

Transducer array,

Figure 2 shows a second embodiment of the invention

Sound transducer assembly and

Figure 3 shows a process for the preparation of the inventive

Transducer array.

FIG. 1 shows a sectional view in the xz plane of the first embodiment of a sound transducer arrangement 100. The sound transducer arrangement 100 shows, by way of example, three sound transducer elements or flexural transducer elements 115, which are arranged parallel to one another. A bending transducer element 115 in this case comprises a piezoelement 104, a membrane 114 which uses a Finishing layer 103 is formed, a hole plate carrier 101 and

Damping material. The acoustic transducer assembly 100 includes a

Punch plate carrier 101, which has a plurality of through holes 111 and holes. The perforated plate carrier 101 has an upper side and a

Bottom on, which are arranged opposite each other. The passage openings 111 are arranged concentrically to the piezoelements 104, wherein each passage opening 111 in each case accommodates a piezoelement 104 which is introduced from the upper side into the passage opening 111 or terminates flush with the upper side. The piezo elements 104 have a smaller diameter than the passage openings 111. In other words, the piezo element 104 is located within the passage opening 111 or the hole. Each piezo element 104 has a first electrode 105 and a second electrode 106. The first electrode 105 is connected by means of a wire connection, for example, with an amplifier circuit and acts as a signal line or

Signal contact. The second electrode 106 is electrically conductively connected by means of an adhesive layer 107 to the terminating layer 103. The termination layer 103 is connected to an electrical ground, for example the amplifier circuit ground. That is, the second electrode 105 is grounded, thereby performing EMC shielding.

Alternatively, the piezo elements 104 can be electrically conductively connected via two wire connections to the electrical ground and the amplifier circuit. For this purpose, the second electrode 106 is contacted over the edge of the piezoelectric element 104, so that on the side of the first electrode 105 there are two separate electrode regions, which can be contacted separately from one another. In this case, the piezoelements 104 can be connected to the terminating layer 103 with an electrically nonconductive adhesive layer.

Each bending transducer element 115 has a first connecting region 108 which adjusts or ensures the edge clamping of the bending transducer element 115 or the membrane 114. The term first connection region 108 is understood here to mean the regions in which a mechanical connection takes place between the end layer 103 and the perforated plate carrier 101. The first connection regions 103 are concentric about the passage openings 111 arranged and have a larger diameter than the

Through holes 111.

The first connection regions 108 are annular and include welds. This means the welds are circular and self-contained. The welds divide the top layer 103 provided with piezo elements 104 into areas with defined vibration mechanical edge restraints. These oscillatory regions above the passage openings 111 form the vibration membrane of the individual bending transducer elements. The welds have a diameter of 0.1 mm to 1.0 mm, preferably 0.25 mm - 0.5 mm, and a lateral distance of 0.1 mm - 1.0 mm to the through holes 111 on.

Around the first connection regions 108, second connection regions 109 are arranged concentrically. In this case, the second connection regions 109 have a lateral distance from the first connection regions 108. The second connection portions 109 also include welds. Optionally, around the second connection regions 109 there may be further concentrically arranged connection regions, which likewise have weld seams. This serves for improved decoupling between two sound transducer elements.

In the edge region of the final layer 103 and in the edge region of the

Punch plate carrier 101, a third connection portion 110 is provided. The term edge region is understood here to mean an area with a lateral distance to the outer edge of the outer layer of 0.1 mm-1 mm.

The piezoelectric elements 104 have a thickness of 100 μηι - 750 μηι, of 150 μηι - 500 μηι. The perforated plate carrier 101 has a thickness of 0.5 mm - 15 mm, preferably 1 mm - 10 mm.

The final layer 103 has a thickness of 50 μηι - 750 μηι on. The

Finishing layer 103 is overpaintable and protects the sound transducer assembly 100 from moisture, liquids and mechanical effects. Optionally, a plastic film may be arranged on the finishing layer 103. The Plastic film is preferably with an epoxy resin adhesive on the

Final layer 103 glued. The epoxy adhesive also acts as a tolerance compensation for the realization of particularly flat surfaces. For this purpose, the epoxy adhesive can be scrape. The plastic film comprises, for example, polyimide or a composite material of metal and plastic or carbon fiber fabric and resin.

In one embodiment, the end layer 103 comprises metal, e.g. As stainless steel, steel or an aluminum alloy. That means that

Finishing layer 103 is completely electrically conductive.

In another embodiment, the end layer 103 plastic, z. B. PES, PVDF, glass fiber composites or

Carbon fiber composites, wherein the side of the end layer 103, which is connected to the perforated plate support 101, a metal layer.

The damping material is preferably silicone-containing.

The basic shape of the piezo elements 104, the bending transducer elements 115 and the passage openings 111 are arbitrary. Preferably, they have regular shapes, z. Square, rectangular, polygonal, circular or elliptical. In a sound transducer assembly 100, the basic shapes of the piezo elements 104, flexural transducer elements 115, and through holes 111 may be the same or different.

The acoustic transducer assemblies 100 may have a number of 2 - 250

Have sound transducer elements, preferably 5-50.

FIG. 1b shows a plan view of the first embodiment of the sound transducer arrangement 100 according to the invention. By way of example, three bending transducer elements 115 are shown, which are arranged parallel to one another or in a line to one another. In the plan view, the rectangular end layer 103 is shown, which are the three

Piezo elements 104 covered. Furthermore, the first connection region 108, which adjusts the edge stress of the respective bending transducer, is the second connection region 109, which acts as a decoupling between the bending transducers and the third connection area 110, for example

is configured rectangular and acts as a seal of the sound transducer assembly shown. FIG. 2 shows a sectional illustration in the xz-plane of the second embodiment of FIG

Sound transducer assembly 200. Features of Figure 2, which illustrate the same features as in Figure 1, have identical rear positions of the reference numerals as in Figure 1. In FIG. 2, the end layer 203 has a plurality of subregions, wherein in each case a subregion is arranged on a passage opening and closes or closes it. That is, the end layer comprises a plurality of individual parts, each of which functions as a diaphragm 214, since they are arranged above the piezoelectric elements 204.

FIG. 3 shows the method 300 for producing a sound transducer arrangement, which has a perforated plate carrier with a plurality of through openings, a plurality of piezo elements and a terminating layer. The method 300 starts with a step 310, in which second electrodes of the piezo elements are connected to the terminating layer. In a following step 320, first electrodes of the piezoelectric elements are electrically connected or contacted by wire bonding. In this case, the first electrode of the second electrode is located

across from. In a following step 330, the terminating layer and the perforated plate carrier are connected by means of first connecting regions,

for example, with welds. In a following step 340, the passage openings are at least partially filled with a damping material.

The transducer assemblies 100 and 200 find in motor vehicles, moving or stationary machines, such as robots, driverless

Transport systems, logistics systems in warehouses, vacuum cleaners, lawnmowers application. Furthermore, the acoustic transducer assemblies 100 and 200 may be used in e-bikes, electric wheelchairs and assistive devices to assist physically disabled persons.

Claims

claims

1. Sound transducer assembly (100) comprising

• a hole plate carrier (101) with a plurality of through holes (111),

• a plurality of piezo elements (104), each piezo element (104) having a first electrode (105) and a second electrode (106) facing the first electrode (105) of the second electrode (106) and a respective piezo element (104) within one Through opening (111) is arranged and

A termination layer (103), wherein the termination layer (103) is arranged above the perforated plate carrier (101) and the piezoelements (104), wherein the second electrodes (106) of the piezoelements (104) are electrically conductively connected to the termination layer (103) .

characterized in that

the end layer (103) and the hole plate carrier (101) first

Connecting regions (108) concentrically around the

Through openings (111) are arranged, wherein the first

Connection regions (108) each have a larger diameter than the passage openings (111) and the first connection regions (108) are designed annular.

Second sound transducer assembly (100) according to claim 1, characterized in that the cover layer (103) and the hole plate carrier (101) second connecting portions (109) which concentrically around the

Through openings (111) are arranged, the second connecting portions (109) have a larger diameter than the first

Connection regions (108) and the second connection regions (109) are designed annular.

3. sound transducer assembly (100) according to any one of the preceding claims, characterized in that the first connecting portions (108) each have a weld.

4. sound transducer assembly (100) according to one of claims 1 to 3, characterized in that the cover layer (103) is integrally formed.

5. A sound transducer assembly (100) according to any one of claims 1 to 3, characterized in that the terminating layer (103) comprises a plurality of sections, wherein in each case a portion of the terminating layer (103) is electrically conductively connected to a piezoelectric element (104).

6. sound transducer assembly (100) according to one of claims 2 to 4, characterized in that the second connection regions (109) a

Weld seam have.

7. A sound transducer assembly (100) according to any one of claims 1 to 4 and 6, characterized in that the finishing layer (103) and the

Punch plate carrier (101) have a third connection region (110) which mechanically connects an edge region of the terminating layer (103) with an edge region of the perforated plate carrier (101).

8. sound transducer assembly (100) according to claim 7, characterized in that the third connection region (110) has a weld.

9. A method (300) for producing a sound transducer assembly comprising a perforated plate carrier having a plurality of through holes, a plurality

Piezo elements and a finishing layer with the steps:

Connecting (310) second electrodes of the piezo elements to the terminating layer,

Contacting (320) first electrodes of the piezoelements by wire bonding, wherein the first electrodes are arranged opposite to the second electrodes,

• Connecting (330) the finishing layer and the perforated plate carrier by means of a weld and

Partial filling (340) of the through holes with a

Damping material.