EP2363211B1 - Signalling device comprising an electrical acoustic signal generator - Google Patents

Description

Field of application and state of the art

The invention relates to a signaling device with an electric acoustic signal from piezoceramic.

From the DE 102010005654 A1 It is known to design such a signaling device with a piezoceramic disk on a metal membrane so that the piezoceramic disk together with the metal membrane is fixedly arranged or soldered on a carrier. Thus, both an electrical contact and a fastening is achieved.

From the JP 60098795 A and the GB 2282932 A Signalers are known with piezoceramic disk and metal diaphragm, wherein the signal transmitter is held only between two outer circumferential rings as a carrier of a housing. A housing base has each arranged in holes Federblechstreifen or springy wires for electrical contacting to the signal generator.

From the EP 456968 A2 is a signal transmitter known with a piezoceramic disk with a metal diaphragm. He is held with an elastic ring and an annular housing n its outer edge.

From the DE 19626293 A1 For example, an ultrasound transducer is known having an annular body with an opening, which has metallic components with free ends that are resilient and form an electrical contact with an ultrasonic sensor to be applied thereto. The exact nature of the mounting of the ultrasonic sensor on the ring body is not recognizable.

Task and solution

The invention has for its object to provide an aforementioned signaling device, can be avoided with the problems of the prior art and in particular a gentler attachment for the piezoceramic can be achieved.

This object is achieved by a signaling device with the features of claim 1. Advantageous and preferred embodiments of the invention are the subject of further claims and are explained in more detail below. The wording of the claims is incorporated herein by express reference.

It is provided that the electrical acoustic signal transmitter has a piezoceramic disk on a metal diaphragm, wherein the signal generator is arranged or fastened on a printed circuit board as a carrier of the device. In this case, the signal transmitter is arranged both with or on the piezoceramic disk as well as on the metal membrane with an electrical contacting to conductor tracks or contacts or the like. provided on the support forming an electrical connection.

According to the invention, a contact on the support for a contact with the pressed-on piezoceramic disk is provided as a contact. Furthermore, bow-shaped or clip-like holding means are provided to secure the signal generator to the carrier, wherein the holding means abut against the signal generator or attack him. Furthermore, the holding means form an electrical contact with the metal membrane and thus the other contact with the signal generator. In this case, the signal transmitter is solderless connected to the carrier and the electrical contacts. Thus, it can be achieved that a thermal load of the signal transmitter or the piezoceramic is not necessary. The failure rate of the piezoceramic discs is therefore lower. Furthermore, as holding means, as will be explained below in detail, simple components are used which are simpler and less expensive can be made available as complex finished plastic parts.

Compared to the aforementioned DE 102010005654 A1 also the carrier itself can be made simpler. Thus, usually on the support first made the attachment of the bow-shaped or clip-like holding means, which can either be inserted into corresponding holes for attachment. An alternative is SMD components that can be soldered on. Also inserted in holes retaining means can be additionally soldered for improved attachment, in particular for an electrical contact to the signal generator or the metal membrane soldering with a conductor track or the like. is beneficial.

At least one retaining means can substantially span the signal generator, in particular cross its central region. As a result, a relatively good attachment of the signal transmitter to the carrier is already achieved, wherein such a holding means can also form an electrical contact with the signal transmitter or the metal diaphragm, if the piezoceramic disk, which advantageously has a slightly smaller diameter than the metal diaphragm, to the carrier points. As a further holder can then be provided that a resonator is provided over the signal generator, on the same side of the carrier as the signal generator. Advantageously, the resonator housing covers the signal generator and contains it, so to speak. Such a resonator housing is generally known and advantageously designed as a Helmholtz resonator. If this resonator is not much larger than the signal generator and is firmly connected to the carrier, for example by inserting projections in holes in the carrier, it can thereby prevent lateral slipping out of the signal generator under the holding means out. Since such a resonator housing is usually provided anyway or is very advantageous, the total cost does not increase.

In a further development of the invention, not only one, but a plurality of separate holding means may be provided, which are provided together on the signal generator for attachment to the carrier. For example, they may be similar or similar and may be lateral hook projections or the like. holding a signal generator pushed into or under it.

Alternatively, a plurality of separate holding means may be formed differently. Thus, a holding means can advantageously be formed substantially rigid and over-grip, so that a signal generator can be pushed underneath.

To fix the signal transmitter in the retracted position is a second resilient holding means as latching hooks or the like. formed, can be pressed under the hook projection of the signal generator and is then fixed both at this end by the resilient retaining means and, above all, at another area by the overlapping of the holding means. In this case, the two holding means may be provided on opposite areas of the signal generator. This is generally advantageous, regardless of how the brackets are formed to secure the carrier relatively securely.

Holding means can advantageously be designed so that they secure the signal generator in multiple directions or fix on the carrier. On the one hand, this may be a fixture that prevents lateral slippage or displacement of the signal generator. Furthermore, lifting or releasing the signal transmitter in the direction away from the carrier can be prevented. This fastening direction is the more important or the holding means should particularly advantageously prevent the signal transmitter can move away from the carrier. A safeguard against lateral movement can also take place, for example, in the aforementioned manner by means of an overlapping resonator housing.

Holding means against a lateral displacement of the signal generator do not necessarily have to overlap like a hook or like a bow. They can also be simply a kind of lateral stop.

An electrical contact of a piezoceramic disc can be done in an embodiment of the invention via a resilient contact element. This can be particularly advantageously attached as a separate part to the carrier and then connected or soldered electrically to a conductor track. This is particularly advantageous realized together with flexible or resilient holding means for the signal generator, so that a certain flexibility in the holder of the signal generator, which allows, for example, a simple insertion, not by the holding means itself, but just by the electrical contact.

There are also embodiments conceivable in which a holding means as a kind of bracket the signal generator, although largely surmounted, but not completely. Such a so-called cantilevered spring arm can form a lateral fixation for the signal generator, possibly even more than on one side, for example on two or three sides.

Holding means may advantageously consist of resilient sheet metal or metal strips which are bent differently and possibly even connected. If they are fastened to the carrier, in particular already with the signal transmitter inserted, then they can have an angled and multiply curved course, for example as a kind of quadrangular border around the signal transmitter with a bridging.

These and other features will become apparent from the claims but also from the description and drawings, wherein the individual features each alone or more in the form of sub-combinations in an embodiment of the invention and in other fields be realized and advantageous and protectable Represent embodiments for which protection is claimed here. The subdivision of the application into individual sections as well as intermediate headings does not restrict the general validity of the statements made thereunder.

Brief description of the drawings

Fig. 1

eine erste erfindungsgemäße Ausgestaltung einer Signalgebereinrichtung in schräger Draufsicht und im Schnitt und

Fig. 2 bis 4

alternative Ausgestaltungen von Signalgebereinrichtungen.

Embodiments of the invention are shown schematically in the drawings and are explained in more detail below. In the drawings show:

Fig. 1

a first inventive embodiment of a signaling device in an oblique plan view and in section and

Fig. 2 to 4

alternative embodiments of signaling devices.

Detailed description of the embodiments

In Fig. 1 an inventive signaling device 11 is shown, on the left in an oblique plan view and right in a sectional view. A signal generator 12 is, as the sectional view shows well, as usual from a piezoceramic disk 14 which is attached to a metal diaphragm 15. The signal generator 12 is located with the piezoceramic disk 14 down on a circuit board 17. In this case, the printed circuit board 17 next to printed conductors, not shown, on a contact pad 18, on which rests the piezoceramic disk for electrical contacting. The signal generator 12 is overlapped by a resonator housing 19, which is shown by dashed lines. This does not necessarily have to be provided, but is very advantageous. Furthermore, it can not only improve the acoustics of the signaling device 11, but also generally serve in addition to the attachment of the signal generator 12. It may be attached to the circuit board 17 in the usual way, for example, with protruding projections in holes inserted therein by clamping.

The main attachment of the signal generator 12 to the circuit board 17 by means of two brackets 22a and 22b, of which at least one advantageously consists of thin sheet metal. The brackets 22 are hook-shaped or angled and overlap the signal generator 12. So press it to the circuit board 17 and hold it so firmly. The headband 22 can be supported and soldered with projections in the form of soldering tips 23a and 23b in the printed circuit board 17, ie with the so-called THT (through hole technology). Alternatively, they may be formed as SMD components, so that no holes in the circuit board 17 must be provided. Thus, the retaining bracket 22, at least if they are made of metal, also form an electrical contact with the metal membrane 15 and thus the other electrical contact to the signal generator 12th

When arranged in Fig. 1 the signal generator 12 can be laterally inserted after attachment of the headband 22 to the circuit board 17 and clamped. For this purpose, it is also possible that the headband 22 are bent slightly downwards in the upper region and thus produce a spring action for better retention of the signal generator 12. Finally, the resonator housing 19 can be plugged or fastened over it.

In the signaling device 111 according to Fig. 2 is a signal generator 112 surrounding, one-piece metal strip provided for mounting, which surrounds the signal generator on three sides. It may also be four pages. Thus, three retaining clips 122a, 122b and 122c are formed. From the middle headband 122b goes from an upper bracket 122d and engages the signal generator 112 to press it both down against a circuit board 117 and turn to contact the metal diaphragm 115 at the top of the signal generator 112 electrically. The lower contact again takes place via a contact pad 118. The retaining clips 122a to 122c can either each have a soldering tip 123 in each case in order to allow a stable mounting of the signal generator 112. Alternatively, only one or two of the retaining clip 122 may have such a soldering tip. Then that's it Inserting the holding assembly in the circuit board 117, especially if it is to be automated, easier and safer and more accurate possible. It can also be an SMD component again.

The signal generator 112 is inserted here from the free side between the three retaining brackets 122a to 122c, wherein the specially curved design of the upper retaining bracket 122d facilitates insertion. The final placement of a Resonatorgehäuses in turn completes the attachment process. If four circumferential headband are provided, the signal generator 112 could be slid obliquely from above under the upper headband 122d and then, so to speak, from above between the four circumferential headband engage, in turn, he is held by the upper headband 122d.

In the signaling device 211 according to Fig. 3 four individual brackets 222a to 222d are provided. Two opposing mounting brackets 222a and 222c are formed only as upstanding short strips with the task to form only a lateral stop for a signal generator 212.

The intermediate support bracket 222b is similar to those of Fig. 1 formed at least at an angle to both form a lateral stop and to prevent lifting of the signal generator 212 from a printed circuit board 217. In yet another embodiment of the invention, it can not only be formed simply angled, similar to in Fig. 1 but also form a kind of pocket, in which the signal generator 212 can be at least partially inserted.

Finally, although the fourth retaining clip 222d is again angled, it is more like a hook with a top hooked upper hook. To insert the signal generator 212 is slid obliquely from above with one end under the headband 222b and guided over the headband 222d. He then goes downstairs the circuit board 217 is pressed and then locks with the other end under this bracket 222 d. An electrical contact to the metal membrane 215 can be done via one of the headband 222b and 222d, possibly also both. Below is again via a contact pad 218 a contact.

As can be seen, in this holding arrangement, the signal generator 212 is completely secured by the retaining clips 222a to 222d and actually requires no further attachment. Nevertheless, a resonator housing 219 can also be retrofitted here.

In Fig. 4 another signaling device 311 is shown, which is designed similar to that in FIG Fig. 2 , Three retaining clips 322a to 322c in turn surround a signal generator 312 on three sides in the manner of a strip. One or more of them, or all of them, may again be fastened to a printed circuit board 317 with a soldering tip 323. A fourth retaining clip 322b spans the enclosed area, extending from the retaining clip 322a to the retaining clip 322c. This retaining clip 322d is bent downwards, so that when inserting a signal generator 312 from the open side, it presses against the printed circuit board 317 and a contact pad 318 for fastening and electrical contacting. Furthermore, the retaining clip 322d serves as an electrical contact to the metal membrane 315. Compared to Fig. 2 So here is continuous upper headband provided, which has no free end.

As you can see, especially in the brackets in 2 and FIG. 4 one-piece arrangements of headband be used. These can be advantageously worked out of a metal sheet or, for example, punched out and then bent into appropriate shape. Their attachment to a printed circuit board can be done for example via the mentioned, einzusteckenden and soldering soldering tips. Alternatively, it may be SMD components that have neither soldering tips nor holes in the circuit board. They are then fastened or soldered to corresponding metallic fields on the upper side of the printed circuit board.

Some of the headband may, as has been mentioned, be made of plastic instead of metal. Because of the simplest possible electrical contact with the upper metal membrane of the signal generator, it is advantageous if this no separate contact or metallic contact spring is needed, but this is taken from one of the headband. Of course, it is also possible to combine plastic headband with metal headband. One-piece arrangements of retaining clips, for example according to the Fig. 2 and 4 , have the advantage that they are easier to assemble or in a single operation. On the one hand, they may be a bit heavier and more complex to produce, and on the other hand, they may be more delicate when attached.

The advantage that can be achieved with the invention, namely that neither a soldering of the piezo signal generator is necessary nor the resulting thermal load, can be seen very well from the embodiments. The respective mounting method is also very simple and suitable for use.

Claims (14)

1. Signalling device (11, 111, 211, 311), comprising an electrical acoustic signal generator (12, 112, 212, 312) including a piezoceramic disc (14, 114, 214, 314) on a metal membrane (15, 115, 215, 315) and having a circuit board (17, 117, 217, 317) as a support for disposing the signal generator thereon, wherein the signal generator both on the piezoceramic disc and on the metal membrane is provided with an electrical contacting to conductive tracks or contacts (18, 118, 218, 318) on the circuit board, wherein one contact (18, 118, 218, 318) is provided on the circuit board for resting against the pressed on piezoceramic disc (14, 114, 214, 314), wherein the signal generator (12, 112, 212, 312) is connected to the circuit board (17, 117, 217, 317) and the electrical contactings by solderless joint, wherein the signal generator is fastened to the circuit board by means of bracket-type or clamp-type retainer means (22a/b, 122a-d, 222a-d, 322a-d) which rest or engage on said circuit board, wherein the retainer means form an electrical contacting to the metal membrane (15, 115, 215, 315), and wherein conductive tracks and contacts (18, 118, 218, 318) are provided on the circuit board (17, 117, 217, 317) for an electrical connection to the signal generator (12,112,212,312).
2. Signalling device according to claim 1, wherein a retainer means (122d, 322d) essentially straddles the signal generator (112, 312).
3. Signalling device according to claim 2, wherein said retainer means is exclusively fastening the signal generator to the circuit board.
4. Signalling device according to any one of the preceding claims, wherein a plurality of separate retainer means (22a/b, 122a-d, 222a-d, 322a-d) are provided and operating together on a signal generator (12, 112, 212, 312) and fasten said generator to the circuit board (17, 117, 217, 317), respectively.
5. Signalling device according to any one of the preceding claims, wherein the retainer means (22a/b, 122a-d, 222a-d, 322a-d) are fastened on the circuit board (17, 117, 217, 317) and are inserted into corresponding holes and are fixedly soldered, or are configured as SMD components and soldered on.
6. Signalling device according to any one of the preceding claims, wherein two retainer means (22a/b, 122a/c, 222a/c, 222b/d, 322a/c) are provided on opposite areas of the signal generator (12, 112, 212, 312) on the circuit board (17, 117, 217, 317) and retain the signal generator fixed in position on the circuit board.
7. Signalling device according to any one of the preceding claims, wherein one retainer means (222b) is designed to be essentially rigid and kind of overlapping for inserting the signal generator (212) below, wherein for fixing the signal generator (212) in the inserted below position a second resilient retainer means (222d) is designed as a latching hook or the like.
8. Signalling device according to claim 7, wherein the second resilient retainer means (222d) is in an area of the signal generator (212) opposite to the first retainer means (222b).
9. Signalling device according to any one of claims 1 to 6, wherein the retainer means (22a/b, 122a-d, 222a/c/d, 322a-d) are flexible and/or resilient-elastic.
10. Signalling device according to any one of claims 1 to 6, wherein the retainer means (22a/b, 122a-d, 222a-d, 322a-d) are designed such that they fasten the signal generator both laterally and in the direction away from the circuit board.
11. Signalling device according to any one of the preceding claims, wherein electrical contacting to the piezoceramic disc is via a resilient contact element.
12. Signalling device according to claim 11, wherein the retainer means is mechanically fastened to the circuit board as a separate part and is electrically connected to a conductive track.
13. Signalling device according to any one of the preceding claims, wherein the signal generator (12, 112, 212, 312) with the piezoceramic disc (14, 114, 214, 314) is facing towards the circuit board (17, 117, 217, 317).
14. Signalling device according to any one of the preceding claims, wherein a resonator housing (19, 119, 219, 319) is provided over the signal generator (12, 112, 212, 312), wherein the resonator housing (19, 119, 319) constitutes a retaining safeguard for the signal generator (12, 112, 312) to prevent removal from the retainer means (22a/b, 122a-d, 322a-d) as a lateral path delimiter.

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