Abstract
An armature having a U-shaped element having a first leg portion and a second leg portion and an attachment portion. The attachment portion has a first leg and a second leg and a central portion connected to the legs, such as an E-shaped portion, where the first leg portion is connected to the central portion. A transducer can include such armature.
Claims
1. An armature comprising: a U-shaped element having a first leg portion and a second leg portion, an attachment portion having at least a first leg and a second leg and a central portion connected to the legs, where the first leg portion is connected to the central portion.
2. A transducer comprising a housing and an armature, where: the armature comprises: a flat elongated portion defining a longitudinal axis, having a first and a second end and defining a first plane, and one or more fastening portions attached to the housing, where a waist portion is provided between the flat elongated portion and each fastening portion, each waist portion and fastening portion being positioned outside of a second plane comprising the longitudinal axis and being perpendicular to the first plane.
3. An armature for a moving armature receiver comprising: a flat elongated portion having a first and a second end and defining a plane, the elongated portion extending between the first and second legs, a first and a second sheet extending from the first end, the first sheet having a first portion extending away from the plane on one side of the plane, the second sheet having a second portion extending away from the plane on another side of the plane, and where the first and second portions are attached to the central portion.
4. An armature according to claim 3, wherein the flat, elongated portion comprises a portion formed by the first sheet also extending from the first end to the second end.
5. An armature according to claim 3, wherein the flat, elongated portion comprises a portion formed by the second sheet also extending from the first end to the second end.
6. An armature according to claim 5, further comprising an element between the first and second sheets between the first and second ends.
7. An armature according to claim 5, wherein the first and second sheets are fixed to each other between the first and second ends.
8. An armature according to claim 5, wherein the first and second sheets, between the first and second ends, are movable in relation to each other.
9. An armature according to claim 3, wherein the flat, elongated portion has, at the second end, a bent portion extending in a direction away from the plane.
10. An armature according to claim 3, wherein the flat, elongated portion has a first thickness, in a direction perpendicular to the plane, and wherein the first and second sheets have a second, lower thickness.
11. An armature according to claim 3, wherein the flat, elongated portion has a first width, in the plane, and wherein the first and second sheets have second widths.
12. A moving armature receiver including the armature according to claim 3, and further comprising: a magnet assembly comprising at least one magnet and defining an air gap, a coil defining a coil tunnel, two opposing wall portions, the armature extending through the coil tunnel and the air gap, the first and second legs fixed to the opposing wall portions.
13. A receiver according to claim 12, wherein the wall portions form part of a wall of a housing wherein the armature, magnet assembly and coil are provided.
14. A receiver according to claim 13, further comprising a diaphragm dividing the housing into two chambers, the diaphragm being connected to the flat, elongate portion of the armature.
15. A receiver according to claim 12, wherein the wall portions extend essentially perpendicular to the plane.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0111] In the following, preferred embodiments will be described with reference to the drawing, wherein:
[0112] FIG. 1 illustrates a first embodiment of an armature according to the invention,
[0113] FIG. 2 illustrates a second embodiment of an armature according to the invention,
[0114] FIG. 3 illustrates a transducer comprising an armature according to the invention,
[0115] FIG. 4 illustrates different manners of manufacturing an armature according to the invention
[0116] FIGS. 5A, 5B, and 5C illustrate additional embodiments of an armature according to the invention,
[0117] FIGS. 6A, 6B, 6C, 6D, 6E, 6F, 6G, 6H, and 6I illustrate alternative types of U-shaped armatures,
[0118] FIGS. 7A, 7B, 7C, and 7D illustrate alternative types of E-shaped armatures,
[0119] FIGS. 8A, 8B, 8C, and 8D illustrate different sheet widths and fastening manners,
[0120] FIG. 9 illustrates another embodiment of an armature according to the invention,
[0121] FIG. 10 illustrates how to arrive at the embodiment of FIG. 9 and
[0122] FIG. 11 illustrates another embodiment of an armature according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0123] In FIG. 1, an armature 10 is illustrated being made from a first sheet 14 and a second sheet 16. The sheets are attached to each other along an at least substantially straight, flat portion 12 but flare away from each other to the left. In the extreme left-most portions of the sheets, fastening elements 141/161 are illustrated. These elements or portions may be attached to a structural element, such as a housing, in any desired manner, such as using screws, welding, soldering, glue, press-fitting or the like. In this embodiment, the fastening elements 141/161 comprise a portion of the sheets 14/16 which extend perpendicularly to a first plane defined between the sheets 14/16 in the portion 12 (a plane out of the drawing). Thus, the fastening elements 14/161 may be attached to e.g. a wall perpendicular to this plane.
[0124] It is seen that the portion 12 is thicker and therefore stiffer than the flaring portions, so that when the armature is forced upwardly or downwardly, the main bending will take place in the flaring portions.
[0125] In FIG. 2, another embodiment 10 is seen, still comprising the first and second sheets 14/16 but now connected to a solid portion 12. The sheets 14/16 still flare upwardly and downwardly, respectively, in relation to a plane defined by the flat portion 12, but now the sheets 14/16 extend not only perpendicularly to the plane of the portion 12 but also bend further to have extreme portions or legs 1411/1412/1611/1612 extending in a direction parallel to a direction of the portion 12. Thus, an armature with a general shape of so-called E-shaped armature is obtained with a central portion 18 interconnecting the portion 12 with the legs. Then, the armature may be fixed to any of a surface perpendicular to a longitudinal axis of the portion 12 or surfaces parallel thereto and perpendicular to the plane of the portion 12.
[0126] The outermost portion 121 of the portion 12 may be used for engaging e.g. a drive pin attached to a diaphragm.
[0127] An alternative E-shaped armature is seen in FIG. 10, which may be made of a single sheet of material and which again illustrates the flat, elongated portion 12, the outer portion 121 for the drive pin, the first and second sheets 14 and 16 which are now attached to a U-shaped element formed by the legs 1411 and 1412 and a central portion 18 from which the legs 1411 and 1412 extend. It is seen that the sheets 14 and 16 extend to the upper and lower edges of the central portion 18.
[0128] FIG. 9 illustrates how to arrive at the armature of FIG. 10 by initially providing a flat, X-shaped element and then bending it.
[0129] Naturally, only the legs may be attached to the housing. Alternatively only the central portion. Also, both the legs and central portion may be attached to the housing if desired.
[0130] The armature may of course be made with a wide variety of dimensions. When used in a hearing aid receiver, the overall length of the extreme portions 1411/1412/1611/1612/1411/1412 may e.g. be 4-7 mm and the width thereof (perpendicular to the plane of the flat portion 12) of 0.5-3 mm, such as 1.5 mm.
[0131] In FIG. 3, an armature according to the invention is provided inside a housing 102 together with a coil 108, having a coil tunnel 1081, and a magnet assembly 106 having an air gap 1061. Also provided is a diaphragm 104 dividing the housing interior into two chambers, an upper chamber 1022 and a lower chamber. One or more sound inputs/outputs 1021 may be provided anywhere and in any or both chambers.
[0132] The sheets 14/16 are attached to one or more housing walls, and the portion 12 extends through the coil tunnel 1081 and the air gap 1061. The extreme portion 121 is attached to a drive pin 122 attached to the diaphragm 104 to transfer movement of the diaphragm to the armature or vice versa.
[0133] When the sheets 14/16 are thinner than the portion 12, the bending of the armature is primarily handled by the sheets 14/16, whereby the portion 12 may stay straight, thus generating a more foreseeable translation of the movement caused by the magnets to the diaphragmor vice versa.
[0134] In FIG. 4, three different manners of manufacturing the armature may be seen.
[0135] In the upper illustration, the two sheets 14/16, as in FIG. 1, co-extend and form also the portion 12. The two sheets may, in the portion 12, be fastened to each other, such as by gluing, press-fitting, welding, soldering, gluing or the like.
[0136] Naturally, if the thickness of the portion 12 is desired thicker than the combined thicknesses of the sheets 14/16, a further sheet may be added to the portion 12, such as between the sheets 14/16 or on top thereof (or below these).
[0137] If the thickness of the portion 12 is desired thinner than the combined thickness of the sheets 14/16, the sheets 14/16 may be provided thinner (rolling or the like) at the portion 12, or the sheets may, in the bent region, be laminated by additional layers.
[0138] In the centre drawing, the portion 12 is made of a separate element, where the two bent sheets 14/16 are attached at one end to the portion 12. Thus, the sheets 14/16 and the element may be made of different elements, and the thicknesses thereof selected freely.
[0139] In the lower drawing, the upper sheet 14 forms also the portion 12. The lower sheet 16 thus may extend merely from the fastening (extreme left portion) to a position where it is fastened to the portion 12 or the intersection between the bent portion and the portion 12.
[0140] In FIGS. 5A-5C, additional embodiments are illustrated. In FIG. 5A, two bent elements each forms one of the sheets 14/16 and are to the left attached (x'es) to a surface and at the opposite ends (right) attached to each other. In this embodiment, waist portions 19 are provided which define the points of rotation or deformation of the armature. Thus, torsional bending takes place. The two upper waist portions are defined in sidewardly extending portions of the sheet 14 and thus together define a rotation axis extending through the two waists. Thus, the overall bending of the sheet 14 is a rotation at the waists and thus around this axis. The same is the situation for the lower sheet 16.
[0141] In FIG. 5B, two sheets 14 and 16 are each bent to a U-shape and attached to each other (x'es) to form an E-shaped armature. This armature is to be attached to an upper and a lower surface of the transducer.
[0142] In FIG. 5C, two sheets 14 and 16 are each bent and connected to a separate portion 12 forming the vibrating portion of the armature. The sheets 14 and 16 are attached as illustrated in the central portion of FIG. 4, but the overall armature is now E-shaped as seen in FIG. 2.
[0143] FIGS. 6A-6I illustrate a number of alternative embodiments of U-shaped armatures.
[0144] In FIG. 6A, a U-shaped armature is illustrated formed of two U-shaped sheets, one within the cavity of the other, and which are attached (x'es) to have stiffer leg portions than the U-shaped (bottom) deformation portion where a distance exists between the sheets.
[0145] In FIG. 6B, the lower sheet is U-shaped and the upper sheet L-shaped. A leg of one sheet is attached to one of the other. The lower leg of the U-shaped sheet may be attached to a structural element (hatched element), as may the extreme portion of the leg of the L-shaped sheet not attached to the U-shaped sheet. In this manner, the upper legs may be stiffer, as they are attached to each other, so that at vibration, the deformation is handled by the bottom of the U-shaped sheet and the other leg of the L-shaped sheet.
[0146] In FIG. 6C, two U-shaped sheets are provided, where the legs of one sheet is attached to the legs of the other but at positions close to the bottom thereof. Thus, the actual legs of the armature are formed of only one sheet, whereas the bottom thereof is formed by the two sheets in unison.
[0147] In FIG. 6D, a more complex shape of a U-shaped armature is seen. Again, two congruent sheets are seen, one within the other, and which are attached to each other in the legs in order to become stiffer and/or to obtain better magnetic properties. Between the leg portions and the bottom, the sheets have bends increasing the flexibility of these portions so that the legs may remain straight when vibrated.
[0148] In FIG. 6E, an armature is seen formed of two sheets each forming one leg and the bottom of a U-shape. The legs of the sheets are attached to each other and between the opposite ends of the sheets, a separate element is attached, forming the other leg of the U. Thus, the bottoms of the sheets may again form a deformation or bending portion where the leg, in this situation the separate element, may remain straight.
[0149] In FIG. 6F, an L-shaped armature is seen formed of two bent sheets. A first sheet forms a bent portion (left) and a straight portion (right) where the right portion forms the vibrating portion extending through the coil and magnet gap. The second sheet is bent in the same direction as the first sheet and attached to the first sheet close to or at the bent portion. Thus, the bent portion of the armature is formed by the two sheets and the leg is formed by one of the sheets only. The upper sheet may e.g. be attached to a cover of the receiver.
[0150] FIG. 6G illustrates an armature as that seen in FIG. 6F, but where the second sheet is provided below the first sheet.
[0151] In FIG. 6H, a U-shaped armature is seen formed of an inner U-shaped sheet and two straight sheets each attached to a leg of the U-shaped sheet (x'es) Naturally, the outer sheets may be attached at more than one position or along their full length such as by gluing, welding, press fitting or the like. Thus, the legs of the U-shaped armature are stiffer than the bottom thereof which then will form a bending or deformation portion when a leg is vibrated.
[0152] In FIG. 6I, a U-shaped armature is seen formed of two U-shaped sheets, where a first of the sheets forms two straight legs. The other sheet is attached to the bottom or close to the bottom of the first sheet.
[0153] In FIGS. 7A-7D, different alternative E-shaped armatures are illustrated.
[0154] In FIG. 7A, an armature is illustrated formed by two E-shaped sheets attached to each other (x'es) in each of the arms. The central arm has an upwardly directed (could also be downwardly directed) bend of the two sheets at a position where they are not attached to each other in order to facilitate bending at that position.
[0155] In FIG. 7B, one sheet is E-shaped and the other is T-shaped. The central leg and the stem of the T are attached to each other (x es) to form a central portion extending through the coil and magnet gap and to have an increased stiffness and/or better magnetic properties. The top portions of the T have waist portions 19 attached at their extremes (x'es) to the E-shaped armature and forming bending or torsion portions facilitating bending or rotation at these positions when the central leg/stem is vibrated. Again, torsional bending takes place so that a rotational axis through the waists is seen. This axis now lies in the first plane.
[0156] In FIG. 7C, an armature made of an E-shaped sheet and a T-shaped sheet, where the central leg and the stem of the T are attached to each other (x es). The top portions of the T also are attached to the E-shaped armature (x es). In the inserted illustration, it is seen that the stem of the T-shaped sheet is contoured and has as downwardly extending depression at which the stem is attached to the central leg. This depression may extend along all of or a main portion of the stem, so as to form an elongate groove, seen from above, in the stem and along the longitudinal axis thereof. This groove or depression increases the stiffness of the stem and thus of the central leg of the E-shaped armature. Then, the portion of the central leg the closest to the base of the E may act as a bending or deformation portion, such as if this portion does not have the depression and thus is formed of two flat sheets.
[0157] In FIG. 7D, an armature made of an E-shaped sheet and a T-shaped sheet, where the central leg and the stem of the T are attached to each other (x es). The top portions of the T are not attached to the E-shaped armature. In the inserted illustration, a side view is seen from which it is seen that the stem of the T-shaped sheet abuts the central leg but that a distance exists between the top part of the T and the base portion of the E-shaped sheet. An element may be provided (not illustrated) between the upper and lower layer to generate and fix the distance. The armature with this element may then be attached to the housing, such as between two parts of the housing.
[0158] In FIGS. 8A-8D, different alternatives to the embodiment of FIG. 1 are seen as examples of sheet shapes and fastening. These embodiments are viewed along the portion 12 which is seen from the end. In these embodiments, this part is formed by portions of the sheets 14 and 16. Naturally, this is not required for the operation of the bent portions of the sheets 14 and 16. The sheet 14 is illustrated in full lines and the sheet 16 in hatched lines.
[0159] In FIG. 8A, the armature of FIG. 1 is seen where the sheets 14 and 16 have the same width as the portion 12.
[0160] In FIG. 8B, the sheets 14 and 16 are each divided into two portions which may be fastened to the housing.
[0161] FIG. 8C illustrates an embodiment where the sheets 14 and 16 from the bending region have half the width of the portion 12. Compared to the embodiments of FIGS. 8A, B and D, the bending of this embodiment may be un-symmetrical.
[0162] In FIG. 8D, the sheet 16 has a portion with a reduced width provided at the centre of the portion 12 whereas the sheet 14 has two parts as seen in FIG. 8B.
[0163] The reduction of the width of the sheets at the bending regions will affect the bending properties. Thus, the bending may be affected not only by the selection of the material of the sheets and the thickness thereof but also the width thereof as well as the relative positions of the bending portions of the sheets.
[0164] In FIG. 11, another aspect of the invention is illustrated where an E-shaped armature portion is connected to a U-shaped armature portion to arrive at an armature with a laminated central leg, two outer legs and a leg portion which may rest on a bottom of a transducer housing.
[0165] The E-shaped portion, or attachment portion, has legs 1411 and 1412 and a central portion having a basis 18 and a central leg.
[0166] The U-shaped portion has a first leg portion 20 and a second leg portion 20. The first leg portion 20 and the central leg are attached to each other to form the flat, elongated vibrating armature leg 12.
[0167] Naturally, the central leg may be omitted, such as when the first leg portion 20 is attached to the basis 18.
[0168] In general, the armature may be provided in a transducer housing by having the legs 1411 and 1412 engage opposing wall portions and the leg portion 20 engage a bottom of an inner chamber of the transducer housing. Then, the armature position is well defined. When the legs and leg portion are fixed to the wall portions, the armature is not able to move even when a force is exerted on the portion 12.
