Coil assembly for a receiver and method for producing it

Abstract

The invention relates to coil assembly for a receiver and a method for producing it. The coil assembly comprises a plate-shaped substrate and a coil of wire. The coil defines a coil tunnel extending in a length direction from a front opening to a back opening. The substrate extends in the coil. The coil is attached to the substrate. The substrate comprises a connector portion protruding beyond one of the front and back openings of the coil tunnel. The connector portion comprises a conductive material to which a wire of the coil is electrically connected.

Description

[0001] COIL ASSEMBLY FOR A RECEIVER AND METHOD FOR PRODUCING IT

[0002] Field of the invention

[0003] The present invention relates to a coil assembly for a receiver and a corresponding method. The invention further relates to a receiver for a hearing device comprising such a coil assembly. Particularly, the invention relates to a balanced armature receiver and a dualreceiver. The invention further relates to a hearing device comprising such coil assembly, receiver or dual -receiver.

[0004] Background of the invention

[0005] Hearing devices, such as hearing aids, include a receiver for generating sound. Various types of receivers include an electromagnetic coil. An electric signal is applied to coil to induce a changing magnetic field, which causes motion of a movable element of the receiver, such as a membrane, to produce sound. The electromagnetic coil included in a receiver is often simply referred to as "coil".

[0006] EP 1 962 551 A2 describes a balanced armature receiver including an electromagnetic coil.

[0007] Description of the invention

[0008] During production of conventional receivers, the wires of the coil are connected manually to the electronics for driving the receiver (typically a PCB). This is a labor-intensive process. Particularly, the wires have to be picked and placed with great accuracy, and are manually soldered. Moreover, the wires are generally fragile and may become damaged during the production.

[0009] An object of the invention is to overcome these drawbacks, or at least provide an alternative. In particular, the invention aims to provide a coil assembly for a receiver that enables more reliable connecting the coil to the electronics for driving the receiver.

[0010] This aim is achieved by the coil assembly for a receiver according to the present disclosure. The coil assembly comprises a substrate and a coil of wire. The coil defines a coil tunnel extending in a length direction from a front opening to a back opening. The coil is attached to the substrate. The substrate comprises a connector portion protruding beyond the front opening or the back opening of the coil tunnel. The connector portion comprising a conductive material to which a wire of the coil is electrically connected.

[0011] By providing the coil in an assembly that also includes a substrate with a connector portion that extends beyond the coil tunnel, the coil can be connected more easily and reliably to the electronics of the receiver and / or hearing device (e.g. a PCB). Particularly, the substrate is more easy to handle than the coil wire, because the substrate has larger dimensions than the coil wire and is less fragile.

[0012] Therefore, the coil assembly according to the invention reduces the number of manual steps for connecting the coil to electronics and / or reduces the time for making the connecting.

[0013] Moreover, the substrate provides support to the wires, such that they are less likely to be damaged when the coil is connected to the electronics for driving the receiver.

[0014] The wire of the coil generally has two ends ("terminals") for connecting to electronics for driving the receiver. For example, the connector portion of the substrate comprises two separate areas of conductive material that are electrically insulated from each other, wherein each end of the coil wire is connected to a different conductive area.

[0015] For example, the wire of the coil is bonded to the conductive material, e.g. by resistance welding, thermocompression bonding or ultrasonic welding. Preferred embodiments are defined in the dependent claims and in the following paragraphs.

[0016] In an embodiment, the conductive material extends from a bonding area near the coil, to which bonding area the wire is connected, to a connector area further away from the coil. In other words, the wire is connected to the bonding area near the coil, while the conductive material extends beyond said bonding area. This allows connecting the coil to electronics (e.g. a PCB) at some distance from the point where the wires are connected. For example, in a receiver, the connector portion may protrude out of a receiver housing for connecting the coil to electronics (e.g. a PCB) for driving the receiver, while the bonding area remains within the receiver housing. Therefore, the bonding area remains protected inside the housing.

[0017] In an embodiment, the substrate extends in the coil.

[0018] Preferably, the substrate is plate-shaped.

[0019] In an embodiment, the substrate has a top surface, bottom surface and two side surfaces. The coil is attached to the top or bottom surface of the substrate while a gap is provided between the coil (i.e. an inner surface of the coil) and at least one of the other surfaces of the substrate. Preferably, a gap is provided between the coil (i.e. an inner surface of the coil) and each of the side surfaces of the substrate. A coil that is wound tightly around the edges of the substrate may be damaged by those edges. This is avoided by leaving a gap between the coil and the side surfaces of the coil. Additionally or alternatively, a gap is provided between the surface that opposes the surface to which the coil is attached. In other words, the coil is attached to a top (respectively bottom) of the substrate, and a gap is present between the coil and the bottom (respectively top) of the substrate. Preferably, this gap is suitable for receiving an armature of a receiver, for arranging the coil around the armature.

[0020] Optionally, such a gap between the coil and a surface of the substrate is filled with an adhesive. In an embodiment, the coil is attached to the substrate by an adhesive. The adhesive preferably comprises a structural adhesive, such as polyurethane or cyanoacrylate. Preferably, the adhesive comprises epoxy.

[0021] Additionally or alternatively, the coil wire is a self-bonding wire, i.e. the wire comprises a selfbonding glue layer. Upon heating, the glue layer of the wire attaches to the substrate. Use of a self-bonding wire reduces the amount of adhesive needed for attaching the coil to the substrate. In principle, the self-bonding glue layer may suffice for attaching the coil to the substrate, i.e. no additional adhesive is needed. Preferably however, additional adhesive is applied, to achieve a stronger adhesion.

[0022] In a further embodiment, the adhesive attaches the coil to a surface of the substrate (e.g. a top or bottom surface of the substrate), and the adhesive holds the coil at the distance to said surface. The adhesive is preferably electrically insulating.

[0023] In an embodiment, the substrate comprises a non-conductive substrate onto which the conductive material is provided. Preferably, the non-conductive substrate comprises a first printed circuit board, PCB.

[0024] For example, the conductive material is printed on the PCB. For example, the PCB comprises a fiberglass reinforced laminate material, such as FR4.

[0025] In an alternative embodiment, the substrate comprises an electrically conductive substrate, such as a lead frame or other metal substrate. The conductive substrate comprises two coplanar plate sections provided at a distance from each other, wherein the two co-planar plate sections extend in the coil.

[0026] In this alternative embodiment, adhesive is preferably used to attach the coil to a surface of the conductive substrate (e.g. a top or bottom surface of the substrate). The adhesive holds the coil at a distance from the substrate, such that the coil is electrically insulated from the electrically conductive substrate. The adhesive preferably is electrically insulating. Preferably, the substrate comprises a metal that is non-magnetic or at least has a low magnetic permeability, such as austenitic stainless steel.

[0027] An advantage of a metal substrate, such as a lead frame, is that the substrate is bendable. In particular, when the coil assembly is used to produce a receiver, a part of the connector portion that protrudes out of the receiver may be bent. For example, said part is bent at an angle of substantially 90 degrees so that it extends parallel to a exterior wall of the receiver housing. This can be advantageous for bonding the connector portion to a PCB (as will be described below). According to the invention, other materials than metal may be used for providing a bendable substrate. In other words, in an embodiment, the substrate is a bendable substrate, preferably a bendable plate-shaped substrate.

[0028] In an embodiment, the substrate has a thickness of 100 pm or less, preferably 75 pm or less, more preferably 50 pm or less. In an embodiment, the substrate extends beyond the front opening and the back opening of the coil tunnel. Particularly, the connector portion of the substrate protrudes one of the front opening and the back opening of the coil tunnel, while another end of the substrate protrudes beyond the other opening of the coil tunnel. An advantage of the substrate protruding beyond both ends of the coil tunnel is that the coil assembly can be picked and placed more easily. In particular, the coil assembly can be picked and placed without touching the coil. In addition, when assembling a receiver, the ends of the substrate protruding beyond the coil tunnel can be positioned onto a support structure.

[0029] The invention further relates to a receiver for a hearing device, the receiver comprising a coil assembly according to any of the embodiments disclosed herein. Preferably, the hearing device is an in-ear device. Preferably, the hearing device is a hearing aid, more preferably an in-ear hearing aid. Other examples of hearing devices include headphones, particularly in-ear headphones (e.g. earbuds).

[0030] In an embodiment, the receiver is a balanced armature (BA) receiver. A BA receiver is a type of armature comprising a movable armature, that extends through a coil.

[0031] Preferably, the substrate of the coil assembly extends in the coil and the armature extends between the substrate and an inner surface of the coil. In other words, the coil encloses a part of the substrate and part of the armature.

[0032] In an embodiment, the receiver further comprises a second PCB. The second PCB comprises at least one opening configured to receive the connector portion of the coil assembly. The second PCB is provided at an angle of substantially 90 degrees to the length direction of the coil tunnel. An advantage of positioning the second PCB in this manner, is that the second PCB can be positioned close to the housing of the receiver, which makes it easier to electrically ground of the receiver's housing via the PCB.

[0033] Preferably, the second PCB is provided against a back of a housing of the receiver. Preferably, the second PCB is attached to the back of the housing.

[0034] In an embodiment, the receiver comprises a housing in which the coil is arranged. The connector portion of the substrate protrudes out of the housing. The conductive material of the connector portion extends from a bonding area inside the housing to a connector area outside the housing. The wire of the coil is electrically connected to the bonding area inside the housing. Thus, the wire bond is protected by the housing, while the electronics can be connected to the coil via the connector area that protrudes out of the housing.

[0035] The invention further relates to a dual -receiver. The dual receiver comprises two receivers according to any of the embodiments disclose herein. The dual receiver further comprises a third PCB. The third PCB comprises at least two openings configured to receive the connector portions of the coil assemblies of the two receivers. The third PCB is provided at an angle of substantially 90 degrees to the length direction. As described above, an advantage of positioning a PCB at 90 degrees, is that the PCB can be positioned close to the housing of the receiver, which makes it easier to electrically ground of the receiver's housing via the PCB.

[0036] Preferably, the third PCB is provided against a back of a housing of the dual-receiver. Preferably, the third PCB is attached to the back of the housing.

[0037] In embodiments that comprise a PCB provided at an angle of substantially 90 degrees to the length direction (second PCB or third PCB), the substrate is preferably a bendable substrate, such as a lead frame, as described above. An end of the bendable substrate that extends out of the receiver can be bent to lie against the second or third PCB, respectively.

[0038] In this disclosure, the terms "first PCB", "second PCB" and "third PCB" are used as labels to distinguish between them. It is stressed that some embodiments may include the second PCB, without including the first PCB. Likewise, some embodiments may include the third PCB, without including the first PCB.

[0039] The invention further relates to a hearing device comprising the coil assembly, receiver or dual-receiver according to any embodiment disclosed herein.

[0040] The invention further relates to a method for producing a coil assembly for a receiver. The method comprises providing a substrate and a coil of wire. The substrate comprises a connector portion comprising a conductive material. The coil defines a coil tunnel extending in a length direction from a front opening to a back opening. The coil is attached to the substrate such that the connector portion protrudes beyond one of the front and back openings of the coil tunnel. The method further comprises electrically connecting the wire of the coil to the conductive material of the connector portion.

[0041] For example, the wire is connected to the conductive material by resistance welding, thermocompression bonding or ultrasonic welding. An advantage of these bonding methods is that they enable an automated process. In addition, these bonding methods heat the wire, which removes the optional self-bonding layer of the wire (if present).

[0042] Preferably, a plate-shaped substrate is provided, such as a plate-shaped PCB.

[0043] In an embodiment, providing the coil comprises: winding the wire around the substrate.

[0044] In a further embodiment, winding the wire around the substrate comprises: placing the substrate in a holder; winding the wire around the holder to form the coil; and removing the substrate and coil from the holder.

[0045] In a further embodiment, a top surface of the substrate is exposed when the substrate is placed in the holder, while the holder covers at least one other surface of the substrate, such that during winding the wire does not touch said at least one other surface. In particular, the method avoids winding the wire tightly around edges of the substrate, which may damage the wire. In an embodiment, when the substrate is placed in the holder, a top surface of the substrate is positioned below a top surface of the holder, such that during winding the wire does not touch the top surface of the substrate.

[0046] In an embodiment, the method comprises applying an adhesive to the substrate to attach the coil to the substrate. Preferably, the adhesive is applied to the substrate before winding the wire. For example, the adhesive is applied to the substrate's top surface that is exposed when placed in the holder.

[0047] In one example, adhesive is applied to the top surface of the substrate, said top surface being positioned below a top surface of the holder, such that during winding the wire touches the adhesive but does not touch the top surface of the substrate. In this manner, the adhesive attaches the coil to the substrate while holding the coil at a distance to the substrate such that the wire of the coil does not touch the substrate.

[0048] In a further embodiment, the method comprises curing the adhesive after winding the coil. Preferably, the method further comprises pre-curing the adhesive during winding. For example, pre-curing comprises applying heat during winding.

[0049] In an embodiment, providing the substrate comprises: providing a non-conductive substrate, and providing the conductive material onto the non-conductive substrate. For example, the method comprises providing a PCB as the substrate, wherein the conductive material is printed on the PCB.

[0050] The same technical effects as described above in relation to the coil assembly apply to the receiver, dual receiver, hearing device and method of the invention. Moreover, any features of the coil assembly described above can similarly be applied in the receiver, dual receiver, hearing device and method, and vice versa.

[0051] Brief description of the drawings

[0052] In the following, example embodiments will be described with reference to the drawings, wherein:

[0053] Figures 1, 2, 3A, 3B illustrate a method for producing a coil assembly according to an embodiment of the invention, with figures 3A and 3B illustrating the coil assembly thus produced;

[0054] Figures 4 and 5 illustrate steps of assembling a balanced armature receiver according to an embodiment of the invention;

[0055] Figure 6 illustrates a dual-receiver according to an embodiment of the invention;

[0056] Figures 7-9 schematically illustrate further details of the method of Figures 1-3;

[0057] Figure 10 illustrates a coil assembly according to an alternative embodiment of the invention; Figure 11 illustrates a variant of the dual-receiver of figure 6; and

[0058] Figure 12 shows a top view of a substrate for a coil of the dual-receiver of figure 11.

[0059] Detailed description of the drawings

[0060] In figure 1, a plate-shaped PCB 2 is provided as substrate. In this example, the PCB 2 has a thickness of 50 pm. The PCB 2 has a coil winding portion 4 around which a coil is to be wound, and a connector portion 6 for connecting the coil to a PCB of a receiver. The connector portion 6 comprises a bonding area 8 adjacent to the coil winding portion 4, and two pins 10, 12 protruding from said bonding area 8.

[0061] A conductive material is provided onto the connector portion 6 of PCB 2. For example, the conductive material comprises a metal, such as copper or gold. The coil winding portion 4 of PCB 2 is kept free of conductive material. Thus, the coil winding portion 4 forms a non- conductive portion of the substrate and the connector portion 6 forms a conductive portion of the substrate.

[0062] In the example of figure 1, the pins 10, 12 are each provided with a conductive layer 14, 16. The layers are electrically insulated from each other, by gap 18.

[0063] An epoxy adhesive 20 is applied to the coil winding portion 4. In a next step (figure 2), a coil wire 22 is wound around the coil winding portion 4. For example, winding the wire 22 around portion 4 is performed by a winding machine.

[0064] In this example, coil wire 22 is a self-bonding wire, i.e. a wire with a self-bonding glue layer. Alternatively, a wire without self-bonding glue layer can be used.

[0065] The winding process (figure 2) is performed at a temperature at which the adhesive 20 precures. For example, a temperature of at least 100 °C is used. After completing the winding process, the coil assembly is exposed to a higher temperature, to cure the adhesive 20. For example, the coil assembly is removed from the winding machine and placed into an oven for curing the adhesive. For example, the adhesive is cured at a temperature of at least 200°C for at least 30 seconds.

[0066] Similarly, also the self-bonding glue layer of the wire 22 is activated due to the elevated temperature.

[0067] The completed coil is referred to as coil tunnel. As can be seen in figure 3A, the coil tunnel 24 has a front opening F and a back opening B. The connector portion 6 of the PCB 2 protrudes from the back opening B of the coil tunnel 24. In the figures 3-5, the coil tunnel 24 is depicted in a simplified manner, without showing the individual windings.

[0068] The ends 26, 28 of wire 22 are bonded to the connector portion 4 of the PCB 2. Particularly, the ends 26, 28 are bonded at the bonding area 8 of the connector portion 4. A first end 26 of the wire is bonded to conductive layer 14 of pin 10 and a second end 28 is bonded to the conductive layer 16 of pin 12. Pins 10, 12 are thus each electrically connected to a different end 26, 28 of the wire 22. Pins 10, 12 can be used as positive and negative terminal for connecting the coil 24 to other electronics, e.g. electronics of a hearing device.

[0069] Preferably, the wire ends 26, 28 are bonded using an automated bonding machine, for example a machine for resistance welding, a machine for thermocompression bonding or a machine for ultrasonic welding.

[0070] Figure 3B shows a schematic view from the back side B of the coil assembly 30. As illustrated, the epoxy adhesive 20 holds the coil tunnel 24 at some distance from the PCB 2, i.e. the top surface of PCB 2 does not. This is optional: alternatively the coil touches the top surface of the PCB 2.

[0071] Figure 3B further shows that a gap G1 is provided between the lower surface of the PCB 2 and an opposing inner wall of the coil tunnel 24. Further, a gap G2 is provided between the left side of the PCB 2 and the coil tunnel 24 and a gap G3 is provided between the right side of the PCB 2 and the coil tunnel 24.

[0072] The coil assembly 30 thus produced is usable in a receiver. Figures 4 and 5 illustrate, as an example, the assembly of a balanced armature receiver including the coil assembly 30. Figure 4 illustrates a step of combining the coil assembly 30 and the armature 32. In the illustrated example, armature 32 is part of a housing portion 34, wherein the housing portion 34 and the armature 32 are formed as a single piece. The housing portion 34 comprises wall portions 36 that will form part of the side wall of the receiver's housing, once assembled.

[0073] In the coil assembly 30, a gap G1 exist between the lower surface of PCB 2 and the opposing inner wall of the coil tunnel 24, such that the coil tunnel 24 remains partially open. The armature 32 is inserted into the back opening B, as indicated by arrow 33. The armature 32 then extends through the coil tunnel 24.

[0074] Referring to Figure 5, the combination of the housing portion 34 and coil assembly 30 is then placed on a bottom housing part 38. Particularly, the housing portion 34 is placed with its wall portions 36 on the bottom housing part 38, such that coil assembly 30 and armature 32 are positioned in the bottom housing part 38. Permanent magnets 40, 42 are provided that generate a magnetic field in an air gap. The armature 32 extends through the air gap between the magnets 40, 42. The receiver further comprises a diaphragm (not shown) connected to the armature 32. Movement of the armature 32 moves the diaphragm, which produces sound. Movement of the armature 32 is achieved by applying a drive signal to the coil 24 via pins 10, 12. A top housing part (not shown) is placed on top of the wall portions 36 of housing portion 34 to form a complete housing.

[0075] The balanced armature receiver of Figure 5 is similar to the receiver described in EP 1 962 551 A2, except that a novel coil assembly 30 is used, which includes pins 10, 12 that protrude from the receiver's housing. When using the receiver of EP 1 962 551 A2, the ends of the coil's wire have to be individually fed out of the housing and connected to the receiver electronics. This is a complex manual operation, during which the coil wire may damage. In contrast, the receiver of Figure 4 enables connecting the coil to receiver electronics using pins 10, 12. This ensures a robust connection and reduces changing of damaging the wire during production.

[0076] Figure 6 illustrates a dual-receiver 44, that comprises two receivers 46, 48. For example, the two receivers 46, 48 are of the type illustrated in Figure 4, or any other type of receiver including the coil assembly according to the invention. In particular, each receiver 46, 48 comprises a coil assembly that comprises two pins 10, 12 that protrude from the back end B of the receiver's housing, i.e. the dual-receiver 44 comprises two pairs of two pins 10, 12. The dual-receiver 44 further comprises a shared sound outlet 50 at its front end F, wherein the shared sound outlet 50 is connected to the sound outlets of each of the receivers 46, 48.

[0077] The pins 10, 12 of the receivers 46, 48 allow electrically connecting electronics of the dualreceiver 44 to the coils of the receivers 46, 48. In particular, the electronics of the dualreceiver 44 comprise a PCB 52. The PCB 52 is placed against the back of the dual-receiver 44, at an angle of substantially 90 degrees with respect to the length direction of the dualreceiver 44. The PCB 52 is provided with through-holes for receiving the pins 10, 12 of the receivers 46, 48. PCB 52 is provided with a printed circuit. The printed circuit includes a conductive area 54 near the through-holes in PCB 52 for connecting the pins 10, 12 to the PCB 52. For example, the pins 10, 12 are electrically connected to the PCB 52 by soldering. For example, a drop of solder is applied to the conductive layer 16 to electrically connect it to the conductive area 54 of the PCB 52.

[0078] Preferably, the solder connection is formed by a reflow soldering process. Solder, such as solder paste, is applied to the pins 10, 12. For example, the solder is printed or applied using a pneumatic dispenser. The reflow soldering process further comprises heating the dualreceiver 44 in a reflow oven to solder the pins 10, 12 to the PCB 52.

[0079] The printed circuit on the PCB 52 may for example be configured to electrically connect the coils of the receivers 46, 48 PCB 52 (in series or parallel). Alternatively or additionally, the PCB 52 may comprise a conductive area ("pad") for grounding, that is electrically connected to the housing of the dual receiver 44.

[0080] In the illustrated examples, PCB 52 comprises through-holes. Alternatively, PCB 52 may comprise a recess for receiving the pins 10, 12.

[0081] Figure 7-9 illustrate further details of the method for producing a coil assembly of Figures 1-3. In particular, the step of winding the wire 22 around coil winding portion 4 is illustrated in more detail. The PCB 2 is provided with conductive layers 14, 16. The PCB is placed in a holder 56 (figure 7). The holder 56 extends along the side walls of the coil winding portion 4. In this example, the holder 56 has a substantially rectangular recess 58 for receiving the PCB 2. A gap is present between the side walls of the winding portion 4 and the side walls of the holder 56. Alternatively, the holder 56 comprises a recess with a shape that matches the shape of the PCB 2, which reduces the gap between the side walls of winding portion and the side walls of the holder 56.

[0082] A top surface of the PCB 2 is exposed. Adhesive 20 is applied to the top surface (figure 8). The wire 22 is wound around the part of the holder 56 that holds the coil winding portion 4. In a first example, the wire 22 is laid on the top of the PCB 2 during winding, and contacts the pre-cured adhesive 20. The wire 22 does not cross the sharp edges of the PCB 2, but rather is wound around the holder 56, which has smooth rounded edges.

[0083] In a second example, holder 56 has a depth that is slightly greater than the thickness of PCB 2. The exposed top surface of the PCB 2 is thus slightly below the top surface of the holder 56. In particular, the holder 56 has a depth such that, during winding, the wire 22 contacts the pre-cured adhesive 20 provided on the top surface of the PCB 2, but the wire 22 does not contact the PCB 2 directly. When the adhesive 20 is cured, the adhesive 20 holds the wire 22 at a distance from the PCB 22.

[0084] Figure 9 shows the coil assembly after completing the winding operation. A coil tunnel 24 has been produced. Both ends of the wire 22 are held by clamps 60. The holder 56 is removed, and the coil assembly is moved to a next stage of production. A next stage of production includes bonding the wire 22 to the conducting layers 14, 16. A further production step includes curing the adhesive 20.

[0085] Figure 10 shows a variant of the coil assembly 30 of Figure 3. The coil assembly 130 is similar to the coil assembly 30 of figure 3, except that the PCB also protrudes from the back opening B of the coil tunnel 124.

[0086] Similar to coil assembly 30 of figure 3, coil assembly 130 comprises a coil tunnel 124 (illustrated schematically). The coil tunnel 124 has a front opening F and a back opening B. A connector portion 106 of the PCB protrudes from the front opening F of the coil tunnel 24. The connector portion comprises a conductive material to which a wire of the coil 124 is electrically connected. The PCB of coil assembly 130 has a protruding portion 162 that extends beyond the back opening of the coil tunnel 124. Preferably, the protruding portion 162 is non-conductive, i.e. electrically insulating.

[0087] In the illustrated example, the protruding portion 162 comprises two pins for connecting to a supporting structure of a receiver. The invention is not limited to a particular shape of the protruding portion 162. For example, the protruding portion 162 may alternatively comprise a rectangular shape.

[0088] Figure 11 shows a variant of the dual-receiver of figure 6. Dual-receiver 244 comprises two receivers 246 and 248. The two receivers 246, 248 are each similar to the receiver illustrated in Figure 4, except that the substrate of their coil assembly is a bendable substrate, particularly a lead frame. The lead frame comprises two pins 210, 212 that protrude from the back end B of the receiver's housing, i.e. the dual-receiver 244 comprises two pairs of two pins 210, 212. Figure 12 shows the lead frame 202 of the receivers 246, 248 in planar view. The lead frame 202 is a plate-shaped metal substrate. A front part of the lead frame 202 comprises two co-planar plate sections 264, 266. The co-planar plate sections 264, 266 are provided at a distance from each other. The plate sections 264, 266 form a coil winding portion 204 around which a coil wire is to be wound. The coil winding portion 204 joins a connector portion 206 for connecting the coil to a PCB, e.g. PCB 252. The connector portion 206 comprises the two pins 210, 212. The two pins 210, 212 are also provided at a distance to each other.

[0089] An electrically insulating adhesive 220 is applied to the coil winding portion 204. Then, a coil wire is wound around the coil winding portion 204, in a similar manner as described above in relation to figures 7-9. The ends the coil wire are bonded to the connector portion 204 of the lead frame 202: a first end of the wire is bonded to pin 210 and a second end is bonded to pin 212.

[0090] Initially, the two pins 210, 212 are joined via bridging section 268 at a back part B of the lead frame 202. Plate sections 264, 266 are thus provided at an opposite end of the lead frame 202 as the bridging section 268.

[0091] The lead frame 202 initially is a single piece. The bridging section 268 provides constructional strength to the lead frame 202, which is beneficial during winding. Moreover, bridging section 268 is advantageous for picking and placing. After winding the coil around coil winding portion 204, the lead frame 202 is cut along line 270. The cutting removes bridging section 268, such that the lead frame 202 now comprises two parts: a first part comprising the plate section 264 and the pin 212 connected to said section 264, and a second part comprising the plate section 266 and the pin 210 connected to said section 266. These two parts are now electrically insulated from each other, because they are no longer electrically connected via bridging section 268, and a gap exists between the first part and the second part. The two parts are held at a distance to each other by the adhesive 220 that attaches the lead frame 202 to the coil.

[0092] Returning to figure 11, a PCB 252 is placed against the back of the dual-receiver 244, at an angle of substantially 90 degrees with respect to the length direction of the dual-receiver 244. The PCB 252 is provided with through-holes for receiving the pins 210, 212 of the receivers 246, 248. PCB 252 is provided with a printed circuit. The printed circuit includes a conductive area 254 near each through-hole in PCB 252 for connecting the pins 210, 212 to the PCB 252. After the pins 210, 212 are fed through the holes in the PCB 252, their free end is bent 90 degrees, so that they extend parallel to the PCB 252. The pins 210, 212 are then electrically connected to the PCB 252 by soldering. For example, a drop of solder is applied to the pins 210, 212 and the conductive area 254 of the PCB 252. Also here, the PCB 252 may be configured to electrically connect the coils of the two receivers 246, 248 (in series or parallel).

[0093] In this example, the pins 210, 212 are bent. Alternatively, the pins 210, 212 may have such a length that their free ends are located in substantially the same plane as the conductive area 254. In that case, a drop of solder suffices to electrically connect the pins 210, 212 to the PCB 252 (no bending step).

[0094] Embodiments

[0095] 1. A coil assembly for a receiver, comprising:

[0096] - a substrate; and

[0097] - a coil of wire, the coil defining a coil tunnel extending in a length direction from a front opening to a back opening, wherein the coil is attached to the substrate, and the substrate comprises a connector portion protruding beyond one of the front and back openings of the coil tunnel, the connector portion comprising a conductive material to which a wire of the coil is electrically connected.

[0098] 2. The coil assembly of embodiment 1, wherein the conductive material extends from a bonding area near the coil, to which bonding area the wire is connected, to a connector area further away from the coil.

[0099] 3. The coil assembly of embodiment 1 or 2, wherein the substrate extends in the coil.

[0100] 4. The coil assembly of any one or more of the embodiments 1-3, wherein the substrate is plate-shaped.

[0101] 5. The coil assembly of any one or more of the embodiments 1-4, wherein the substrate has a top surface, bottom surface and two side surfaces, and the coil is attached to the top or bottom surface while a gap is provided between the coil and at least one of the other surfaces, preferably a gap is provided between the coil and all of the other surfaces.

[0102] 6. The coil assembly of any one or more of the preceding embodiments, wherein the coil is attached to the substrate by an adhesive, wherein the adhesive preferably comprises a structural adhesive, such as epoxy.

[0103] 7. The coil assembly of the embodiment 6, wherein the coil is attached to a surface of the substrate, wherein the adhesive holds the coil at a distance to said surface.

[0104] 8. The coil assembly of any one or more of the preceding embodiments, wherein the substrate comprises a non-conductive substrate onto which the conductive material is provided, wherein the non-conductive substrate preferably comprises a first printed circuit board.

[0105] 9. The coil assembly of embodiment 7, wherein the substrate comprises a conductive substrate.

[0106] 10. The coil assembly of any one or more of the embodiments 1-6, wherein the substrate comprises an electrically conductive substrate comprising two co-planar plate sections provided at a distance from each other, wherein the two co-planar plate sections extend in the coil. 11. The coil assembly of any one or more of the embodiments 1-10, wherein the substrate has a thickness of 100 m or less, preferably 75 pm or less, more preferably 50 pm or less.

[0107] 12. The coil assembly of any one or more of the preceding embodiments, wherein the substrate extends beyond the front opening and the back opening of the coil tunnel.

[0108] 13. A receiver for a hearing device, the receiver comprising the coil assembly of any one or more of the preceding embodiments.

[0109] 14. The receiver of embodiment 13, further comprising a movable armature that extends through the coil, wherein preferably the armature extends between the substrate and an inner surface of the coil.

[0110] 15. The receiver of embodiment 13 or 14, further comprising a housing in which the coil of the coil assembly is arranged, wherein the connector portion protrudes out of the housing, wherein the conductive material of the connector portion extends from a bonding area inside the housing to a connector area outside the housing, and wherein the wire of the coil is connected to the bonding area inside the housing.

[0111] 16. The receiver of embodiment 15, wherein the substrate is a bendable substrate, and a part of the connector portion that protrudes out of the housing is bent at an angle of substantially 90 degrees.

[0112] 17. The receiver of any one or more of the embodiments 13-16, further comprising a second printed circuit board comprising at least one opening configured to receive the connector portion of the coil assembly, wherein the second printed circuit board is provided at an angle of substantially 90 degrees to the length direction.

[0113] 18. The receiver of embodiments 16 and 17, wherein the bent part of the connector portion is bonded to the second printed circuit board.

[0114] 19. A dual-receiver, comprising two receivers according to one or more of the embodiments 13-16, further comprising a third printed circuit board comprising at least two openings configured to receive the connector portions of the coil assemblies of the two receivers, wherein the third printed circuit board is provided at an angle of substantially 90 degrees to the length direction.

[0115] 20. The dual-receiver of embodiment 19, comprising two receivers according to embodiment 16, wherein the bent part of the connector portions are bonded to the third printed circuit board.

[0116] 21. A hearing device, comprising the coil assembly, receiver or dual-receiver according to any one or more of the preceding embodiments.

[0117] 22. A method for producing a coil assembly for a receiver, the method comprising:

[0118] - providing a substrate comprising a connector portion comprising a conductive material; - providing a coil of wire, the coil defining a coil tunnel extending in a length direction from a front opening to a back opening, wherein the coil is attached to the substrate such that the connector portion protrudes beyond one of the front and back openings of the coil tunnel; and

[0119] - electrically connecting a wire of the coil to the conductive material of the connector portion.

[0120] 23. The method of embodiment 22, wherein providing the coil comprises winding the wire around the substrate.

[0121] 24. The method of embodiment 23, wherein winding the wire around the substrate comprises:

[0122] - placing the substrate in a holder;

[0123] - winding the wire around the holder to form the coil; and

[0124] - removing the substrate and coil from the holder.

[0125] 25. The method of embodiment 24, wherein, when the substrate is placed in the holder, a top surface of the substrate is exposed, while the holder covers at least one other surface of the substrate, such that during winding the wire does not touch said at least one other surface.

[0126] 26. The method of embodiment 24 or 25, wherein, when the substrate is placed in the holder, a top surface of the substrate is positioned below a top surface of the holder, such that during winding the wire does not touch the top surface of the substrate.

[0127] 27. The method of any one or more of embodiments 22-26, wherein an adhesive is applied to the substrate to attach the coil to the substrate.

[0128] 28. The method of the combination of embodiments 26 and 27 , wherein the adhesive is applied to the top surface of the substrate, such that during winding the wire touches the adhesive but not the top surface of the substrate.

[0129] 29. The method of embodiment 27 or 28, as far as dependent on 23, wherein the adhesive is applied to the substrate before winding the wire.

[0130] 30. The method of embodiment 29, further comprising curing the adhesive after winding the coil.

[0131] 31. The method of embodiment 30, further comprising pre-curing the adhesive during winding, wherein pre-curing preferably comprises applying heat during winding.

[0132] 32. The method of any one or more of embodiments 22-31, wherein providing the substrate comprises providing a non-conductive substrate and providing the conductive material onto the non-conductive substrate.

Claims

CLAIMS1. A coil assembly for a receiver for generating sound, comprising:- a plate-shaped substrate; and- a coil of wire, the coil defining a coil tunnel extending in a length direction from a front opening to a back opening, wherein the coil is attached to the substrate, the substrate extending in the coil and the substrate comprises a connector portion protruding beyond one of the front and back openings of the coil tunnel, the connector portion comprising a conductive material to which a wire of the coil is electrically connected.

2. The coil assembly of claim 1, wherein the substrate has a top surface, bottom surface and two side surfaces, and the coil is attached to the top or bottom surface while a gap is provided between the coil and at least one of the other surfaces, preferably a gap is provided between the coil and all of the other surfaces.

3. The coil assembly of claim 1 or claim 2, wherein the coil is attached to the substrate by an adhesive, wherein the adhesive preferably comprises a structural adhesive, such as epoxy.

4. The coil assembly of claim 3, wherein the coil is attached to a surface of the substrate, wherein the adhesive holds the coil at a distance to said surface.

5. The coil assembly of any one or more of the claims 1-4, wherein the substrate comprises a non-conductive substrate onto which the conductive material is provided, wherein the non- conductive substrate preferably comprises a first printed circuit board.

6. The coil assembly of any one or more of the claims 1-4, wherein the substrate comprises an electrically conductive substrate comprising two co-planar plate sections provided at a distance from each other, wherein the two co-planar plate sections extend in the coil.

7. The coil assembly of any one or more of the preceding claims, wherein the substrate extends beyond the front and the back opening of the coil tunnel.

8. A receiver for a hearing device, the receiver being for generating sound, the receiver comprising the coil assembly of any one or more of the preceding claims, the receiver preferably further comprising a movable armature that extends through the coil.

9. The receiver according to claim 8, further comprising a second printed circuit board comprising at least one opening configured to receive the connector portion of the coil assembly, wherein the second printed circuit board is provided at an angle of substantially 90 degrees to the length direction.

10. A dual-receiver, comprising two receivers according to claim 8, further comprising a third printed circuit board comprising at least two openings configured to receive the connector portions of the coil assemblies of the two receivers, wherein the third printed circuit board is provided at an angle of substantially 90 degrees to the length direction.

11. A hearing device comprising the coil assembly, receiver or dual-receiver according to any one or more of the claims 1-10.

12. A method for producing a coil assembly for a receiver for generating sound, the method comprising:- providing a plate-shaped substrate comprising a connector portion comprising a conductive material;- providing a coil of wire, the coil defining a coil tunnel extending in a length direction from a front opening to a back opening, the substrate extending in the coil, wherein the coil is attached to the substrate such that the connector portion protrudes beyond one of the front and back openings of the coil tunnel; and- electrically connecting a wire of the coil to the conductive material of the connector portion.

13. The method of claim 12, wherein providing the coil comprises winding the wire around the substrate.

14. The method of claim 13, wherein winding the wire around the substrate comprises:- placing the substrate in a holder;- winding the wire around the holder to form the coil; and- removing the substrate and coil from the holder.

15. The method of claim 14, wherein, when the substrate is placed in the holder, a top surface of the substrate is exposed, while the holder covers at least one other surface of the substrate, such that during winding the wire does not touch said at least one other surface.

16. The method of claim 14 or claim 15, wherein, when the substrate is placed in the holder, a top surface of the substrate is positioned below a top surface of the holder, such that during winding the wire does not touch the top surface of the substrate.

17. The method of any one or more of claims 13-16, wherein an adhesive is applied to the substrate to attach the coil to the substrate, wherein the adhesive is applied to the substrate before winding the wire, the method further comprising curing the adhesive after winding the coil, the method preferably further comprising pre-curing the adhesive during winding, wherein pre-curing preferably comprises applying heat during winding.

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