Loudspeaker with rolling suspension device

Abstract

The invention describes a loudspeaker (10) with a rolling suspension arrangement, comprising: a radiator (1) movable along a longitudinal axis (X) to generate pressure waves; a basin surrounding the radiator so as to form a liner (C) between the radiator and the basin (2), the liner being delimited by an inner surface (201) of the basin and an outer surface (101) of the radiator; a magnetic circuit (3) defining a path for the circulation of the magnetic field, the magnetic circuit comprising a fixed magnetic element (301) connected to the basin and a movable magnetic element (302) connected to the radiator and movable under the action of the magnetic field to move the radiator in response to an electrical signal to be converted; a ring (4) made of an elastomeric material, coaxial with the longitudinal axis (X) and positioned inside the liner (C) in contact with the outer surface of the radiator and the inner surface of the basin so as to move longitudinally and rollably on the outer and inner surfaces in response to the relative movement between the radiator and the basin.

Description

Technical Field

[0001] The invention relates to a loudspeaker and a method for amplifying sound. Background Art

[0002] Typically, loudspeakers include an electromechanical transducer system for converting a variable electrical signal into a mechanical movement of a radiator in order to generate sound waves. These transducer systems include a magnetic element integrated with a fixed part of the sound diffuser and a movable magnetic element connected to the radiator to move the radiator; in particular, the movable magnetic element - a coil or a magnet - moves under the influence of a magnetic field generated by the integrated magnetic element.

[0003] In this case, there are two types of electromechanical transduction systems. According to the most widespread system, the so-called "moving coil", the integrated magnetic element is a permanent magnet and the movable magnetic element is a coil; the coil is excited by the electrical signal to be converted and the coil moves in response to the interaction with the magnetic field generated by the permanent magnet. An example of a moving coil system is described in patent document US5014323A. Alternatively, according to a system called "moving magnet", the integrated magnetic element consists of a fixed coil and the movable magnetic element is a magnet; the fixed coil is excited by the electrical signal and the movable magnet moves in response to the magnetic field generated by the coil. An example of a moving magnet system is described in patent document EP2550724 in the name of the same applicant.

[0004] Typically, a speaker includes a suspension device connected between the radiator and the basket to allow relative movement between them. However, the suspension device limits the travel between the radiator and the basket and is prone to frequent breakage. In order to increase the travel, a larger suspension device can be used, however, this increases the overall size of the speaker.

[0005] Patent document GB348425A describes a loudspeaker comprising a suspension device made of a tube, which is placed between the basket and the radiator; however, even this document does not meet market needs.

[0006] Patent document EP 4 207 809 A1 by the same applicant describes a loudspeaker comprising a guide device made of a tube; however, this guide device cannot be used for a suspension device. Summary of the invention

[0007] The object of the present invention is to provide a loudspeaker and a method for propagating sound which overcome the above-mentioned disadvantages of the prior art.

[0008] Said object is fully achieved by the loudspeaker and the method for propagating sound according to the invention as characterized in the appended claims.

[0009] In particular, the loudspeaker comprises a radiator. The radiator is movable along a longitudinal axis to generate pressure waves.

[0010] The loudspeaker comprises a basket. The basket surrounds the radiator (around the longitudinal axis) so as to form a lining or hollow space between the radiator and the basket. In particular, the lining is defined by an inner surface of the basket and an outer surface of the radiator. In other words, the basket has an inner surface, i.e. a surface facing the longitudinal axis, and the radiator has an outer surface facing in the opposite direction relative to the longitudinal axis; the inner surface and the outer surface act together to define the lining. The lining surrounds the longitudinal axis.

[0011] Preferably, the lining extends substantially parallel to the longitudinal axis. However, the lining may extend around the longitudinal axis according to other orientations, for example the lining may extend in a conical shape along the longitudinal axis. In particular, the inner surface of the basin frame is formed (substantially) parallel to the longitudinal axis, and the outer surface of the radiator is formed (substantially) parallel to the longitudinal axis.

[0012] The radiator has a peripheral edge. The peripheral edge is formed around the longitudinal axis. In one embodiment, the outer surface of the radiator protrudes from the peripheral edge of the radiator toward the interior of the speaker. Specifically, the outer surface of the radiator protrudes from the peripheral edge of the radiator toward the interior of the liner.

[0013] Preferably, the inner wall of the basin frame and the outer surface of the radiator have substantially the same design around the longitudinal axis. In particular, the inner surface of the basin frame and the outer surface of the radiator are formed around the longitudinal axis so as to define a uniform lining around the longitudinal axis between them.

[0014] Preferably, the inner surface of the frame and the outer surface of the radiator have substantially the same design along the longitudinal axis. In particular, the inner surface of the frame and the outer surface of the radiator are formed parallel to the longitudinal axis and present (substantially) the same height along the longitudinal axis. Preferably, the inner surface of the frame has a main formation direction parallel to the longitudinal axis and the outer surface of the radiator has a main formation direction parallel to the longitudinal axis.

[0015] In one example, the liner can be formed along a forming axis parallel to the longitudinal axis. The liner is formed along the forming axis between the upper opening and the lower opening opposite to the upper opening. Therefore, the inner surface of the basin frame and the outer surface of the radiator are formed parallel to the forming axis of the liner.

[0016] In particular, the upper opening is close to the peripheral edge of the radiator. The upper opening and the lower opening are aligned along the liner forming axis.

[0017] In one embodiment, the lining is open to the external environment of the loudspeaker. Specifically, the lining is open to the external environment through an upper opening. Thus, the upper opening connects the lining to the external environment of the loudspeaker.

[0018] In other words, the liner is open to the external environment of the loudspeaker at the peripheral edge. The sheath is open to the internal environment of the loudspeaker via the lower opening. Thus, the bottom opening connects the liner to the internal environment of the loudspeaker.

[0019] The lining forms an opening to the external environment of the loudspeaker. In this way, the radiator can move freely relative to the longitudinal axis, thereby allowing a larger amplitude. The loudspeaker includes a magnetic circuit. Generally, the magnetic circuit is configured to generate a magnetic field and define a path for the magnetic field to circulate.

[0020] In particular, the magnetic circuit defines a path for the magnetic field to circulate. The magnetic circuit includes a fixed magnetic element. The fixed magnetic element is connected to the basin frame. The magnetic circuit includes a movable magnetic element connected to the radiator. The movable magnetic element can move under the action of the magnetic field to move the radiator in response to the electrical signal to be converted. The movable magnetic element can include a movable magnet or a movable coil. The fixed magnetic element can include a fixed coil and / or one or more fixed magnets. The magnetic circuit can define a transducer.

[0021] According to an example, the movable magnetic element includes a movable coil, and the fixed magnetic element includes one or more fixed magnets; the movable coil is configured to receive an electrical signal to be converted and generate a magnetic field in response to the electrical signal; the one or more fixed magnets are configured to generate a constant magnetic field; the magnetic field generated by the coil and the constant magnetic field generated by the one or more fixed magnets work together to generate a total magnetic field to move the movable coil.

[0022] According to an example, the movable magnetic element includes one or more movable magnets, and the fixed magnetic element includes a fixed coil; the fixed coil is configured to receive an electrical signal to be converted and generate a magnetic field in response to the electrical signal; the one or more movable magnets are configured to move under the action of the generated magnetic field.

[0023] The loudspeaker comprises a ring. In general, the ring is made of a deformable material. In particular, the ring is made of a plastic material; more particularly, of an elastomeric material. The ring is coaxial with the longitudinal axis and positioned inside the liner. The ring is in contact with the outer surface of the radiator and the inner surface of the basket so as to roll on them. In particular, the ring moves in response to the relative movement between the radiator and the basket. Preferably, the ring moves longitudinally in response to the relative movement between the radiator and the basket. The purpose of the ring is to guide the movement of the radiator relative to the basket and to center the radiator relative to the longitudinal axis.

[0024] The ring made of plastic (or elastomeric) material can be deformed inside the liner, thus forming a rolling pneumatic sealing system.

[0025] The ring can advantageously be used instead of a classic suspension arrangement between the radiator and the basket at the peripheral edge (profile or rim) of the radiator.

[0026] With the radial dimensions of the loudspeaker being equal, the ring allows a greater travel between the radiator and the basket than the suspension; in fact, in order to allow a greater travel between the radiator and the basket, a radially larger suspension is required, and therefore the size of the radiator needs to be reduced; however, this factor significantly reduces the overall performance of the loudspeaker.

[0027] Furthermore, since the ring has a reduced radial dimension, the mass of the system and therefore the total inertia of the system is limited, thus allowing greater accelerations and therefore better performance levels to be obtained.

[0028] Furthermore, the use of a ring is particularly advantageous for manufacturing non-axisymmetric loudspeakers, such as square radiating pistons, for example with rounded corners and generally more complex shapes, which may be difficult to manufacture using conventional suspension arrangements.

[0029] The ring is also easy to install between the radiator and the basin frame because, unlike the suspension device, it does not require the use of adhesive during assembly, thus significantly simplifying assembly and any replacement. In addition, the cost of the ring is relatively low and standard production methods (such as those used to produce O-rings) can be used to manufacture the ring.

[0030] According to one embodiment, the radiator comprises a flange. The flange extends along the longitudinal axis between a first end and a second end opposite the first end. The flange defines an outer surface of the radiator. Preferably, the flange extends parallel to the longitudinal axis. However, the flange may extend according to a different orientation relative to the longitudinal axis, for example extending transversely to the longitudinal axis. The flange surrounds the longitudinal axis. The radiator may have a conical shape (thus, the radiator may be a cone) or a cylindrical shape (thus, the radiator may be a piston).

[0031] In one example, the flange is connected to the peripheral edge of the radiator. The flange is formed from the first end to the second end toward the interior of the speaker. Therefore, the flange is formed from the second end to the first end toward the exterior of the speaker. In other words, the first end is close to the external environment of the speaker and the second end is away from the external environment of the speaker. In particular, at the first end, the flange is in communication with the external environment of the speaker. The first end (at least partially) defines an upper opening of the liner.

[0032] In one embodiment, the loudspeaker comprises a main part (or membrane). The main part may have a conical shape (i.e., the main part may taper towards the longitudinal axis) or a planar shape (i.e., the main part may be formed in a plane perpendicular to the longitudinal axis). In particular, the conical shape of the membrane defines a cone-type radiator, while the planar shape of the membrane defines a piston-type radiator.

[0033] In particular, the main part (membrane) defines a peripheral edge (i.e. a peripheral edge of the radiator). More specifically, the main part (membrane) is formed as a flange connected to the radiator, preferably at the peripheral edge of the main part and at a first end of the flange. Typically, the main part and the flange have different designs around the longitudinal axis (i.e. different inclinations relative to the longitudinal axis). In particular, the flange is formed parallel to the longitudinal axis, while the main part is formed in a direction transverse to the longitudinal axis (in the case of a planar design, the direction is perpendicular to the longitudinal axis).

[0034] In one embodiment, the angle between the main part and the flange of the radiator is less than or equal to 90 degrees. Preferably, the main part forms an angle with the flange equal to 90 degrees in the case of a planar design of the main part and an angle less than 90 degrees in the case of a conical design of the main part. It is observed that this angle is evaluated between the inner surface (opposite to the outer surface) of the radiator and the main part of the radiator.

[0035] The fact that the flange is formed from the first end toward the inside of the loudspeaker (or more specifically, the fact that the angle formed between the main portion and the flange is less than or equal to 90 degrees) ensures the compactness of the loudspeaker itself.

[0036] In one embodiment, the frame has a main part formed longitudinally (parallel to the longitudinal axis). Preferably, this longitudinally formed main part defines the inner surface of the frame (and thus defines the lining). The frame may have an auxiliary part formed parallel to the longitudinal axis. The main part and the auxiliary part are connected to each other. In particular, the auxiliary part is at substantially the same height as the peripheral edge of the radiator (in particular, as the peripheral edge of the main part of the radiator). At the auxiliary part of the frame, the frame may have mounting holes for attaching a speaker (attached to a support outside the speaker). In case the main part of the radiator has a planar design, the main part of the radiator and the auxiliary part of the frame are formed along the same plane; in particular, the main part of the radiator and the auxiliary part of the frame are at the same height along the longitudinal axis.

[0037] According to an example, the loudspeaker comprises a peripheral edge (i.e. the aforementioned peripheral edge) positioned in a plane transverse to the longitudinal axis, preferably at a first end of the flange. The peripheral edge protrudes towards the interior of the liner. The peripheral edge can be arranged in the radiator and / or in the basin. Preferably, at the first end of the flange (i.e. at the peripheral edge), the radiator and the basin are separated from each other by an air volume open to the external environment.

[0038] The radiator may include a profile; the profile may extend around the longitudinal axis in a manner having a circular (uniform or elongated along the axis), square, rectangular (with or without rounded corners), etc. The flange may be located at the profile of the radiator. The flange extends along the longitudinal axis corresponding to the shape of the profile of the radiator.

[0039] According to an example, at the first end of the flange, the radiator and the basin are separated from each other by an air volume open to the external environment. Thus, the ring divides the liner into a first space (i.e., an air volume open to the external environment) and a second space (i.e., an air volume isolated from the external environment).

[0040] According to an example, the contour of the radiator defines a peripheral edge of the loudspeaker. According to one embodiment, the peripheral edge protrudes from the flange towards the interior of the liner at a first end of the flange. The peripheral edge is separated from the basket by an air volume open to the external environment.

[0041] According to an example, the basin frame comprises a peripheral edge positioned in a plane transverse to the longitudinal axis. The peripheral edge may protrude towards the interior of the liner at the first end of the flange (or at the peripheral edge of the radiator). The peripheral edge of the basin frame is separated from the radiator (in particular from the first end of the flange or from the peripheral edge of the radiator) by an air volume open to the external environment.

[0042] According to one embodiment, the loudspeaker comprises an additional peripheral edge. The additional peripheral edge is positioned on an additional plane transverse to the longitudinal axis. Preferably, the additional peripheral edge is positioned at the second end of the flange, or it may be positioned at a point between the first end and the second end (e.g. at the midpoint). The additional peripheral edge may be arranged in the flange of the radiator or on the inner surface of the basin frame. The additional peripheral edge protrudes towards the interior of the lining. The ring is configured to roll between the above-mentioned peripheral edge and the above-mentioned additional peripheral edge, preferably along the longitudinal axis. To this end, the above-mentioned peripheral edge and the above-mentioned additional peripheral edge constitute the starting point and the end point of the ring, respectively.

[0043] The liner has a width, namely a radial width. The width is defined in a radial direction relative to the longitudinal axis. The radial width is between the inner surface of the basket and the outer surface of the radiator. The radial width extends along the longitudinal axis so as to decrease towards the first end (i.e. the peripheral edge) and the second end (i.e. the further peripheral edge) of the flange. In other words, the (radial) width of the liner is larger at a stationary point between the first end and the second end of the flange (i.e. between the peripheral edge and the further peripheral edge) and is smaller at the first end and the second end (i.e. the peripheral edge and the further peripheral edge).

[0044] In this way, the ring is recalled towards a point (stationary point) between the first end and the second end, ie between the peripheral edge and the further peripheral edge.

[0045] According to an example, the outer surface of the radiator and / or the inner surface of the basin frame has a concave profile so that the radial width of the liner decreases toward the first end (peripheral edge) and the second end (the other peripheral edge) of the flange (that is, the radial width of the liner decreases toward the first end and the second end of the flange).

[0046] To this end, the concave profile defines a seat for the ring to roll on. According to an example, the radiator, ie the flange of the radiator, may be made integrally with the concave profile, for example by injection moulding.

[0047] According to one embodiment, the ring is positioned in the liner in a fluid-tight manner so that the ring interrupts the liner, dividing the liner into an area close to the external environment (i.e., the first space, i.e., a space open to the external environment) and an area away from the external environment (i.e., the second space or a space isolated from the external environment).

[0048] According to one example, the ring is located in the liner in such a way that it is compressed by a predetermined amount relative to the rest position in a direction transverse to the longitudinal axis.

[0049] According to an embodiment in which the width of the liner narrows towards the first and second ends of the flange, the ring is recalled towards the area of ​​the liner having a greater radial width.

[0050] According to one embodiment, the fixed magnetic element and the basket define a fixed structure, and the radiator and the movable magnetic element define a movable unit. The loudspeaker may comprise a guide arrangement configured for guiding the alternating longitudinal movement of the movable unit.

[0051] The guide means comprises an inner surface extending around a guide axis, the guide axis being preferably longitudinally oriented. The guide means comprises an outer surface extending around the guide axis and surrounding the inner surface to define a gap.

[0052] The guide means comprises an annular element, preferably a spring. The spring is closed on itself to form a ring. The spring is positioned in the gap in contact with the inner and outer surfaces of the guide means to roll on the inner and outer surfaces, preferably longitudinally, in response to relative movement between the inner and outer surfaces.

[0053] An inner surface of the guiding device may be connected to the fixed structure and an outer surface of the guiding device may be connected to the movable unit, or vice versa.

[0054] According to one embodiment, the speaker includes an outer body. The outer body may extend between a first end and a second end opposite to the first end. The outer body may extend longitudinally. The outer body may define a support for a movable coil or a movable magnet, that is, the movable coil or the movable magnet may be connected to the outer body. According to an example, the radiator includes a paper cone, and the outer body may be connected to the paper cone of the radiator. According to an example, the outer body is arranged in the radiator. For example, the outer body may constitute a portion having a longitudinal extension of the radiator.

[0055] According to an example, the outer body defines an outer surface of the guiding means.

[0056] According to one embodiment, the loudspeaker comprises a further ring. Features concerning the ring according to the invention should be considered to apply to the further ring as well.

[0057] Preferably, the further ring is made of an elastomeric material and is positioned inside the liner coaxially with the longitudinal axis and in contact with the outer surface of the radiator and the inner surface of the frame so as to move longitudinally rollingly on the outer surface of the radiator and the inner surface of the frame in response to the relative movement between the radiator and the frame. The aforementioned ring and the aforementioned further ring define a pair of rings. The aforementioned further ring together with the aforementioned ring has the purpose of reducing the swaying phenomenon.

[0058] According to one embodiment, the loudspeaker comprises an intermediate peripheral edge arranged in the radiator, in particular on the outer surface of the radiator, or in the basin, in particular on the inner surface of the basin. The intermediate peripheral edge protrudes towards the inside of the lining. The intermediate peripheral edge is located between the above-mentioned peripheral edge and the above-mentioned further peripheral edge. In particular, the ring is located between the peripheral edge and the intermediate peripheral edge so as to roll between the peripheral edge and the intermediate peripheral edge. The further ring is located between the further edge and the intermediate peripheral edge so as to roll between the intermediate peripheral edge and the further edge.

[0059] The present invention also provides a method for propagating sound.

[0060] The method comprises the steps of preparing a radiator. The radiator is movable along a longitudinal axis to generate a pressure wave. The radiator may be manufactured according to one or more features of the present invention.

[0061] The method comprises the step of preparing a basin frame. The basin frame can be manufactured according to one or more features of the present invention. The basin frame surrounds the radiator (around the longitudinal axis) so as to form a lining between the radiator and the basin frame. In particular, the lining is defined by the inner surface of the basin frame and the outer surface of the radiator. The lining can be manufactured according to one or more features of the present invention.

[0062] The method comprises the step of preparing a magnetic circuit. The magnetic circuit can be manufactured according to one or more features of the present invention. In particular, the magnetic circuit defines a path for the magnetic field to circulate. The magnetic circuit comprises a fixed magnetic element connected to a basin frame. The magnetic circuit comprises a movable magnetic element connected to a radiator.

[0063] The method comprises the step of generating a magnetic field in response to an electrical signal to be converted.

[0064] The method includes the step of moving a movable magnetic element in response to a generated magnetic field to move the radiator along a longitudinal axis.

[0065] The method comprises the step of rolling the ring. The ring can be manufactured according to one or more features of the invention. In particular, the ring is made of a deformable material, in particular a plastic material, more in particular an elastomeric material. The ring is coaxial with the longitudinal axis and is positioned inside the liner. In particular, the ring rolls on the outer surface of the radiator and the inner surface of the basin frame and moves (longitudinally) in response to the relative movement between the radiator and the basin frame.

[0066] According to one embodiment, the radiator comprises a flange, that is, the method comprises the step of preparing a flange in the radiator. The flange extends longitudinally along the longitudinal axis between a first end and a second end opposite the first end. The flange defines an outer surface of the radiator. Preferably, the flange extends parallel to the longitudinal axis. However, the flange may extend according to a different orientation relative to the longitudinal axis, for example transversely to the longitudinal axis. The flange surrounds the longitudinal axis. The radiator may have a conical shape (thus, the radiator may be a paper cone) or a cylindrical shape (thus, the radiator may be a piston).

[0067] According to an example, the method comprises the step of preparing a peripheral edge. The peripheral edge can be manufactured according to one or more features of the invention. The peripheral edge is positioned in a plane transverse to the longitudinal axis, preferably at a first end of a flange of the radiator. The peripheral edge protrudes towards the interior of the liner. The peripheral edge can be arranged in the radiator and / or in the basin frame.

[0068] Preferably, the peripheral edge is separated from the basin frame by an air volume open to the external environment, for example at the first end of the flange (ie at the peripheral edge).

[0069] According to an example, the method comprises the step of preparing a further peripheral edge. The further peripheral edge can be manufactured according to one or more features of the invention. The further peripheral edge is positioned on a further plane transverse to the longitudinal axis, preferably at the second end of the flange, or it can be positioned at a point between the first end and the second end (for example at the midpoint). The further peripheral edge can be arranged in the flange of the radiator or on the inner surface of the basin frame. The further peripheral edge protrudes towards the inside of the lining. The method may comprise the step of rolling the ring, preferably along the longitudinal axis, between the above-mentioned peripheral edge and the above-mentioned further peripheral edge. To this end, the above-mentioned peripheral edge and the above-mentioned further peripheral edge constitute the starting point and the end point of the ring, respectively.

[0070] The liner has a width, namely a radial width. The width is defined in a radial direction relative to the longitudinal axis. The radial width is between the inner surface of the basin frame and the outer surface of the radiator. The radial width extends along the longitudinal axis so as to decrease towards the first end (i.e. the peripheral edge) and the second end (i.e. the further peripheral edge) of the flange. In other words, the (radial) width of the liner is larger at a stationary point between the first end and the second end of the flange (i.e. between the peripheral edge and the further peripheral edge) and is smaller at the first end and the second end (i.e. the peripheral edge and the further peripheral edge). The method may include the step of recalling the ring towards a point (stationary point) between the first end and the second end (i.e. between the peripheral edge and the further peripheral edge).

[0071] According to an example, the outer surface of the radiator and / or the inner surface of the basin frame has a concave profile so that the radial width of the liner decreases toward the first end (peripheral edge) and the second end (the other peripheral edge) of the flange (that is, the radial width of the liner decreases toward the first end and the second end of the flange).

[0072] The method may include the step of compressing the ring by a predetermined amount relative to the rest position in a direction transverse to the longitudinal axis inside the liner. The ring is compressed by a smaller amount in the region having the largest radial region width in that region and is thus recalled towards the region having the larger radial width.

[0073] According to one embodiment, the fixed magnetic element and the basin frame define a fixed structure, and the radiator and the movable magnetic element define a movable unit; the method may include a step of guiding the longitudinal movement of the movable unit by a guiding device. The guiding device can be manufactured according to one or more features of the present invention. The guiding device includes an inner surface extending around a guiding axis, and the guiding axis is preferably longitudinally oriented. The guiding device includes an outer surface extending around the guiding axis and surrounding the inner surface to define a gap. The method may include a step of preparing an annular element (preferably a spring). The spring itself is closed to form a ring. The spring is positioned in the gap in contact with the inner surface and the outer surface. The guiding step can be performed by rolling the spring on the inner surface and the outer surface, preferably moving longitudinally, in response to the relative movement between the inner surface and the outer surface. The inner surface can be connected to the fixed structure, and the outer surface can be connected to the movable unit, and vice versa.

[0074] According to one embodiment, the method includes the step of preparing an outer body. The outer body may extend between a first end and a second end opposite to the first end. The outer body may extend longitudinally. The outer body may define a support for a movable coil or a movable magnet, that is, the movable coil or the movable magnet may be connected to the outer body. According to an example, the radiator includes a paper cone, and the outer body may be connected to the paper cone of the radiator. According to an example, the outer body is arranged in the radiator. For example, the outer body may constitute a part having a longitudinal extension of the radiator. According to an example, the outer body defines an outer surface of the guide device.

[0075] According to one embodiment, the method comprises the step of rolling the further ring.The features concerning the ring according to the invention should be considered to apply also to the further ring.

[0076] Preferably, the further ring is made of plastic material and is coaxial with the longitudinal axis and is positioned inside the liner, on the outer surface of the radiator and the inner surface of the basin, and moves longitudinally in response to relative movement between the radiator and the basin. The above ring and the above further ring define a pair of rings.

[0077] According to one embodiment, the method comprises the step of preparing an intermediate peripheral edge, which is arranged in the radiator, in particular on the outer surface of the radiator, or in the basin frame, in particular on the inner surface of the basin frame. The intermediate peripheral edge protrudes towards the inside of the lining. The intermediate peripheral edge is located between the above-mentioned peripheral edge and the above-mentioned further peripheral edge. In particular, the ring is located between the peripheral edge and the intermediate peripheral edge so as to roll between the peripheral edge and the intermediate peripheral edge. The further ring is located between the further edge and the intermediate peripheral edge so as to roll between the intermediate peripheral edge and the further edge. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] These and other features of the present invention will become more apparent from the following detailed description of preferred non-limiting example embodiments thereof, with reference to the accompanying drawings, in which:

[0079] - Figure 1A and Figure 2A A loudspeaker according to the prior art is shown;

[0080] - Figure 1B , Figure 1C , Figure 2B , Figure 2C , Figure 3A and Figure 3B shows a cross section of a loudspeaker according to one or more aspects of the present invention;

[0081] - FIG. 4A to FIG. 4D shows a cross section of a radiator and basket of a loudspeaker according to one or more aspects of the present invention;

[0082] - FIG. 5A to FIG. 5C A loudspeaker according to one or more aspects of the present invention is shown;

[0083] - FIG. 6A to FIG. 6G A transducer for a loudspeaker according to one or more aspects of the present invention is shown.

[0084] 10-speaker; 100-transducer; 1-radiator; X-longitudinal axis; 101-outer surface of radiator; 102-flange; 102A-first end of flange; 102B-second end of flange; 103-peripheral edge; 104-additional peripheral edge; 105-intermediate peripheral edge; 106-outer body; 2-basin; 201-inner surface of basin; C-lining; 3-magnetic circuit; 301-fixed magnetic element; 301A-central core; 301B-outer core; 301C-fixed coil; T-air space; 302-movable magnetic element; 4-ring; 4'-additional ring; 5-speaker support ring; 601-inner surface of guide device; 602-outer surface of guide device; 603-spring; G-guide axis; I-gap; 301Ca-first straight portion of fixed coil; 301Cb-fixed The second straight section of the fixed coil; 301Cc-the third straight section of the fixed coil; 301Cd-the fourth straight section of the fixed coil; 301Ba-the first section of the outer core; 301Bb-the second section of the outer core; 301Bc-the third section of the outer core; 301Bd-the fourth section of the outer core; 302a-the first magnet; 302b-the second magnet; 302c-the third magnet; 302d-the fourth magnet; 60-angle element; 7a-upper half shell; 7b-lower half shell; 71-longitudinal section of the upper half shell 7a; 301Aa-the central section of the central core; 301Ab-the side section of the central core; 40-actuating element; 40a-the first actuating element; 40b-the second actuating element; 40c-the third actuating element; 40d-the fourth actuating element; 41-a separate actuating element; 42-connector. DETAILED DESCRIPTION

[0085] The number 10 in the drawings indicates a loudspeaker. The loudspeaker 10 comprises a radiator 1. The radiator 1 is movable along a longitudinal axis X so as to generate pressure waves. The loudspeaker 10 comprises a basket 2. The loudspeaker 10 comprises a magnetic circuit 3, which is configured to generate a magnetic field and defines a path for the circulation of the magnetic field.

[0086] The magnetic circuit 3 includes a fixed magnetic element 301 connected to the basin frame 2. The magnetic circuit 3 includes a movable magnetic element 302, which is connected to the radiator 2 and can move under the action of the magnetic field to move the radiator 2 in response to the electrical signal to be converted. The movable magnetic element 302 may include one or more magnets or coils.

[0087] The fixed magnetic element 301 may include a coil. The coil includes a plurality of coils wound around a winding axis; preferably, the winding axis coincides with the longitudinal axis X. The coil is configured to generate a magnetic field when an electrical signal to be converted passes through the coil. The magnetic circuit 3 defines a transducer for the loudspeaker 10. The fixed magnetic element 301 includes a central core 301A and an outer core 301B. The central core 301A extends along the longitudinal axis X between a first end near the radiator 1 and a second end opposite to the first end. The outer core 301B is located outside the central core 301A so as to define an air gap T in which a movable coil or a movable magnet (i.e., one or more movable magnets) can move longitudinally. The outer core 301B is directly or indirectly connected to the inner core 301A, preferably at the second end of the inner core 301A. The inner core 301A and the outer core 301B are configured to allow a magnetic field to circulate within the ferromagnetic circuit 3.

[0088] The magnetic field generated (by the coil) interacts with the inner core 301A and the outer core 301B (i.e., it circulates within the inner core 301A and the outer core 301B). The coil (in the case of a movable coil) or one or more magnets (in the case of a movable magnet) interacts with the magnetic field so as to move longitudinally within the air gap T.

[0089] The basket 2 surrounds the radiator 1 around the longitudinal axis X so as to form a lining C between the radiator 1 and the basket 2. In particular, the lining C is defined by an inner surface 201 of the basket 2 (i.e., the inner surface 201 facing the longitudinal axis X) and an outer surface 101 of the radiator 1 (i.e., the outer surface 101 facing the opposite direction with respect to the longitudinal axis X). The lining C extends parallel to the longitudinal axis X.

[0090] In particular, the radiator 1 comprises a flange 102 extending along the longitudinal axis X between a first end 102A and a second end 102B opposite the first end 102A and defining an outer surface 101 of the radiator 1 .

[0091] The loudspeaker 10 comprises a ring 4 made of an elastomeric material. The ring 4 is coaxial with the longitudinal axis X and is positioned inside the liner C in contact with the outer surface 101 of the radiator 1 and the inner surface 201 of the basket 2 so as to roll on the outer surface 101 of the radiator 1 and the inner surface 201 of the basket 2 in response to the relative movement between the radiator 1 and the basket 1.

[0092] The radiator 1 comprises a peripheral edge 103 positioned in a plane transverse to the longitudinal axis X at a first end 102A of the flange 102. The peripheral edge 103 projects towards the inside of the liner C. For example, the peripheral edge 103 is connected to the profile of the radiator 1. At the first end 102A of the flange 102, the radiator 1 and the basin frame 2 are separated from each other by an air volume open to the external environment.

[0093] The radiator 1 comprises a further peripheral edge 104 positioned on a further plane transverse to the longitudinal axis X. The aforementioned plane and the further plane are parallel to each other. The further peripheral edge 104 is located at the second end 102B of the flange 102. The further peripheral edge 103 protrudes towards the inside of the liner C.

[0094] The ring 4 is configured to roll inside the liner C between the peripheral edge 103 and the further peripheral edge 104. To this end, the peripheral edge 103 and the further peripheral edge 104 define respectively the starting point and the end point of the ring 4.

[0095] The lining C has a radial width between the inner surface 201 of the basket 2 and the outer surface 101 of the radiator 1, which extends along the longitudinal axis X so as to decrease towards the peripheral edge 103 and the further peripheral edge 104. The lining C has a maximum radial width at a point between the peripheral edge 103 and the further peripheral edge 104; this point included defines the equilibrium point about which the ring 4 is recalled.

[0096] According to an example, the outer surface 101 of the radiator 1 and / or the inner surface 201 of the basket has a concave profile so that the radial width of the lining C decreases towards the peripheral edge 103 and towards the further peripheral edge 104 .

[0097] The ring 4 is positioned in the liner C in a fluid-tight manner so that it interrupts the liner C and divides the liner C into a region close to the external environment and a region remote from the external environment. Furthermore, the ring 4 is located inside the liner C so as to be compressed by a predetermined amount relative to the rest position in a direction transverse to the longitudinal axis X. Thus, when moving between the peripheral edge 103 and the further peripheral edge 104, the ring 4 is subjected to a return force which positions the ring 4 at the position where the liner C has the maximum radial width.

[0098] The loudspeaker 10 may include an additional ring 4' made of an elastomeric material. The additional ring 4' is coaxial with the longitudinal axis X and is positioned inside the liner C in contact with the outer surface 101 of the radiator 1 and the inner surface 201 of the basket 2 so as to move longitudinally in a rolling manner on the outer surface 101 of the radiator 1 and the inner surface 201 of the basket 2 in response to the relative movement between the radiator 1 and the basket 2. To this end, the ring 4 and the additional ring 4' move together and define a pair of rings. The radiator 1 may include an intermediate peripheral edge 105 positioned on a middle plane transverse to the longitudinal axis X. The middle plane is parallel to the above-mentioned plane and the above-mentioned additional plane. The intermediate peripheral edge 104 is located between the peripheral edge 103 and the additional peripheral edge 104. In this case, the ring 4 is located between the peripheral edge 103 and the intermediate peripheral edge 104, and the additional ring 4' is located between the intermediate peripheral edge 105 and the additional peripheral edge 104. The ring 4 rolls between the peripheral edge 103 and the intermediate peripheral edge 105 , whereas the ring 4 ′ rolls between the intermediate peripheral edge 105 and the further peripheral edge 104 .

[0099] According to an example, the lining C has a radial width between the inner surface 201 of the basket 2 and the outer surface 101 of the radiator 1, which extends along the longitudinal axis X so as to decrease towards the peripheral edge 103, the intermediate peripheral edge 105 and the further peripheral edge 104. The lining C has a maximum radial width at a first point between the peripheral edge 103 and the intermediate peripheral edge 105 and at a second point between the intermediate peripheral edge 105 and the further peripheral edge 104; the first point defines the equilibrium point at which the ring 4 is recalled, and the second point defines the equilibrium point at which the further ring 4' is recalled.

[0100] According to an example, the outer surface 101 of the radiator 1 and / or the inner surface 201 of the basket have a concave profile so that the radial width of the lining C decreases towards the peripheral edge 103 , towards the further peripheral edge 104 and towards the intermediate peripheral edge 105 .

[0101] The further ring 4 is also positioned in the liner C in a fluid-tight manner. In this way, the ring 4 and the further ring 4' interrupt the liner C, thereby dividing the liner C into a region close to the external environment, a region remote from the external environment, and an intermediate region between the close region and the remote region. The further ring 4' can also be located inside the liner C so as to be compressed by a predetermined amount relative to the rest position in a direction transverse to the longitudinal axis X. Therefore, when moving between the intermediate peripheral edge 105 and the further peripheral edge 104, the further ring 4' is subjected to a return force, which positions the further ring 4' at the position where the liner C has the maximum radial width (i.e., the second point).

[0102] According to one embodiment, the speaker 10 includes an outer body 106 extending between a first end and a second end opposite to the first end. The outer body 106 extends longitudinally. The outer body 106 may define a support for a movable coil or a movable magnet, that is, the movable coil or the movable magnet may be connected to the outer body 106. According to an example, the radiator 1 includes a cone, and the outer body 106 may be connected to the cone of the radiator. According to an example, the outer body 106 is disposed in the radiator 1. For example, the outer body 106 may constitute a portion having a longitudinal extension of the radiator 1. The outer body 106 may be partially inserted into the air space T.

[0103] The loudspeaker 10 may include a loudspeaker support ring 5 located between the longitudinal portion 106 (ie the outer body) and the basket. The loudspeaker support ring 5 is configured for centering the radiator 1 and the basket 2 along the longitudinal axis X.

[0104] According to one embodiment, the fixed magnetic element 301 (i.e., the inner core 301A, the outer core 301B and the coil 301B (if fixed)) together with the basin frame 2 define a fixed structure. According to an example, the movable magnetic element 302 (i.e., the movable coil or the movable magnet) together with the radiator 1 defines a movable unit. The movable unit moves along the longitudinal axis X by reciprocating motion. The speaker 10 may include a guide device configured to guide the alternating longitudinal movement of the movable unit. The guide device includes an inner surface 601 extending around a longitudinally oriented guide axis G. The guide device includes an outer surface 602 extending around the guide axis G and surrounding the inner surface 601 to define a gap I. The guide device includes a spring 603, which is closed on itself to form a loop and is positioned in the gap I in contact with the inner surface 601 and the outer surface 602 of the guide device to roll on the inner surface 601 and the outer surface 602 of the guide device when moving longitudinally in response to the relative movement between the inner surface 601 and the outer surface 302.

[0105] The inner surface 601 of the guiding device may be connected to the fixed structure and the outer surface 602 of the guiding device may be connected to the movable unit, or vice versa. Preferably, the inner surface 601 of the guiding device is connected to the fixed structure and the outer surface 602 is connected to the movable unit.

[0106] According to one embodiment, the outer body 106 may define an outer surface 602 of the guide means. The outer core 301B of the magnetic circuit 3 may define an inner surface 601 of the guide means. The outer body 106 may form part of the movable unit.

[0107] according to FIG. 6A to FIG. 6GIn the example embodiment shown purely by way of example, the stationary coil 301C comprises a plurality of straight sections, in particular a first straight section 301Ca, a second straight section 301Cb, a third straight section 301Cc and a fourth straight section 301Cd. The first straight section 301Ca, the second straight section 301Cb, the third straight section 301Cc and the fourth straight section 301Cd are joined together by a curved connecting section. The straight sections face each other in pairs. The straight sections are located on the same plane transverse to the longitudinal axis X and are symmetrically positioned relative to the longitudinal axis X. According to the example shown, the straight sections define a square in a plane transverse to the longitudinal axis X.

[0108] The outer core 301B of the ferromagnetic circuit 301 may include a plurality of parts, in particular a first part 301Ba, a second part 301Bb, a third part 301Bc and a fourth part 301Bd. Parts of the plurality of parts of the outer core 301B may be separated from each other. The plurality of parts of the outer core 301B are positioned transversely to the plurality of straight portions of the fixed coil 301C so as to define a plurality of gaps T.

[0109] The transducer 100 may include a plurality of magnets, in particular a first magnet 302a, a second magnet 302b, a third magnet 302c and a fourth magnet 302d. Each of the plurality of magnets is located in a corresponding gap T of a plurality of gaps T defined by a plurality of straight portions of the coil 301C and a plurality of portions of the outer core 301B. Each of the plurality of magnets can move in the air gap T along a corresponding movement direction parallel to the longitudinal axis X.

[0110] Therefore, when the coil 301B is excited to generate an excitation magnetic field, movement of the plurality of magnets is caused along the corresponding movement direction. The movement of the magnets causes oscillation of the radiator 1 to which the transducer 100 is connected. The magnets are joined to each other by corresponding angle elements 60, which are located at the curved connection section of the coil 301C, so as to form a rigid structure that can move along the longitudinal direction X. In particular, the rigid structure does not allow movement in a direction transverse to the longitudinal axis X (i.e., in any direction transverse to the longitudinal axis X), while it allows movement along the longitudinal direction X.

[0111] Each magnet has an extension transverse to the longitudinal axis X between a first end and a second end; at these ends, each magnet has a south pole and a north pole.

[0112] The sound transducer 100 comprises four guide means, wherein each guide means is coupled to an angle element 60. Each guide means comprises an outer surface 602 defined by the angle element 60. The angle element 60 defines an outer body for the loudspeaker 10. The outer surface 602 extends around a guide axis G parallel to the longitudinal axis X.

[0113] The transducer 100 comprises an upper half shell 7a and a lower half shell 7b. Each guide device comprises an inner surface 601. The inner surface 601 is defined by the upper half shell 7a. In particular, the upper half shell 7a comprises four longitudinal portions 71, which are inserted into the angle element 60 and define the inner surface 601 of the guide device. Therefore, the inner surface 601 extends around the guide axis G. The outer surface 602 surrounds the inner surface 601 in a manner defining a gap I. Each guide device comprises an elastic element 603, preferably a spring, which is closed by itself to form a ring, which is positioned in the gap I in contact with the inner surface 601 and the outer surface 602 to roll on the inner surface 601 and the outer surface 602 when moving longitudinally in response to the relative movement between the inner surface 601 and the outer surface 602. The upper half shell 7a is connected to the inner core 301A of the ferromagnetic circuit 3 in an integral manner; therefore, the inner surface 601 is connected to the inner core 301A through the upper half shell 7a. The corner element 60 is connected to a pair of magnets among the plurality of magnets in an integral manner; for this purpose, the outer surface 602 is connected to the pair of magnets connected to the corner element 60 through the corner element 60. In this way, when the magnet moves along the corresponding moving direction, the outer surface 602 moves together with the magnet and slides relative to the inner surface 601 that remains stationary, and the elastic element 603 rolls between the outer surface 602 and the inner surface 601.

[0114] According to an example, the inner core 301A includes a central portion 301Aa and side portions 301Ab. The outer side portions 301Ab are separated from the outer core 301B by a plurality of gaps T. The side portions 301Ab have a high permeability region near the coil 301C. The high permeability region is defined by a notch transverse to the longitudinal axis X, for example to divide the central core 301A into an upper portion and a lower portion juxtaposed to the longitudinal axis X. According to an example, in the lower portion of the central core 301A, the central portion 301Aa and the side portions 301Ab define a seat for the coil 301C.

[0115] The side portions 301Ab of the upper and lower portions cooperate to form the notched area. The notch may surround the entire perimeter of the coil 301C except at points where the curved line joins.

[0116] The straight portion of the coil 301C is placed beside the central portion 301Aa of the core 301A and the side portion 301Ab of the core 301A.

[0117] The transducer 100 comprises a lower half-shell 7b. The upper half-shell 7a and the lower half-shell 7b are juxtaposed to each other along the longitudinal axis X and are configured to hold a plurality of portions 301Ba, 301Bb, 301Bc and 301Bd of the outer core 301B.

[0118] The transducer 100 may include a mechanical transmission system. The mechanical transmission device may include a plurality of actuating elements 40 (i.e., a first actuating element 40a, a second actuating element 40b, a third actuating element 40c, and a fourth actuating element 40d), which are interposed between corresponding magnets among the plurality of magnets 302a, 302b, 302c, 302d and the radiator 1, and are used to move the radiator 1 in the same direction or in the opposite direction as the magnets; in this way, the movement of the magnet in one direction along the corresponding movement direction corresponds to the movement of the radiator 1 in the same direction or in the opposite direction along the longitudinal axis X.

[0119] According to one aspect of the invention, each of the plurality of actuating elements 40 comprises a separate rotating element 41; each separate rotating element 41 pivots at a connection point on a corresponding portion of a plurality of portions that are a portion of the plurality of portions 301Ba, 301Bb, 301Bc and 301Bd of the outer core 301B. Each actuating element 40 is laterally connected to the angle element 60 so that when the angle element 60 moves longitudinally, the actuating element (particularly the rotating element) rotates and transmits the pattern to the radiator 1 through the connection body 42.

Claims

1. A speaker, comprising: - a radiator movable along a longitudinal axis to generate a pressure wave; - a basket surrounding the radiator so as to form a lining comprised between the radiator and the basket, the lining being delimited by the inner surface of the basket and the outer surface of the radiator; - a magnetic circuit defining a path for the circulation of a magnetic field and comprising a fixed magnetic element connected to the frame and a movable magnetic element connected to the radiator, the movable magnetic element being movable under the effect of the magnetic field so as to cause the radiator to move in response to the electrical signal to be converted; - a ring of elastomeric material coaxial with the longitudinal axis and arranged inside the liner in contact with the outer surface of the radiator and the inner surface of the basin so as to move longitudinally in a rolling manner on the outer surface of the radiator and the inner surface of the basin in response to relative movement between the radiator and the basin.

2. The loudspeaker according to claim 1, wherein The radiator includes a flange extending parallel to the longitudinal axis, extending between a first end and a second end opposite the first end, and defining an outer surface of the radiator.

3. The loudspeaker according to claim 2, wherein: The radiator comprises a peripheral edge positioned at the first end of the flange in a plane transverse to the longitudinal axis, the peripheral edge protruding from the flange towards the interior of the liner, the peripheral edge being separated from the basin by an air space open to the external environment.

4. The loudspeaker according to claim 3, wherein: The radiator includes a further peripheral edge positioned at the second end of the flange in a further plane transverse to the longitudinal axis, the further peripheral edge protruding toward the interior of the liner, the further peripheral edge being arranged on the flange or on the inner surface of the basin frame, and the ring is configured to roll between the peripheral edge and the further peripheral edge along the longitudinal axis.

5. The loudspeaker according to claim 4, wherein: The liner has a radial width relative to the longitudinal axis, the radial width of the liner extending longitudinally so as to decrease toward the first and second ends of the flange.

6. The loudspeaker according to claim 5, wherein: The outer surface of the radiator and the inner surface of the basket each have a concave profile so that the radial width of the liner decreases toward the first end and the second end of the flange.

7. A loudspeaker according to any one of the preceding claims, wherein: The ring is located fluid-tightly inside the liner such that the ring interrupts the liner and divides the liner into a region close to the external environment and a region remote from the external environment.

8. The loudspeaker according to any one of claims 1 to 6, wherein: The ring is positioned within the interior of the liner so as to be compressed a predetermined amount relative to a rest position in a direction transverse to the longitudinal axis.

9. The loudspeaker according to claim 1, wherein The fixed magnetic element and the basin frame define a fixed structure, and the radiator and the movable magnetic element define a movable working unit, and the speaker includes: - a guide device configured to guide the longitudinal reciprocating movement of the movable working unit and comprising an inner surface extending around a longitudinally oriented guide axis, and an outer surface extending around the guide axis and surrounding the inner surface to define a gap; - a spring closed on itself to form a loop, the spring being disposed in the gap in contact with the inner surface and the outer surface so as to roll on the inner surface and the outer surface when moving longitudinally in response to relative movement between the inner surface and the outer surface, The inner surface is connected to the fixed structure, and the outer surface is connected to the movable working unit, or vice versa.

10. A loudspeaker according to claim 9, comprising an outer body extending between a first end and a second end opposite the first end, the outer body extending longitudinally and defining an outer surface of the guide means.

11. A loudspeaker according to any one of claims 1 to 6, comprising an additional ring of elastomeric material, which is coaxial with the longitudinal axis and is arranged inside the lining in contact with the outer surface of the radiator and the inner surface of the basin so as to roll longitudinally on the outer surface of the radiator and the inner surface of the basin in response to the relative movement between the radiator and the basin, and the ring and the additional ring define a pair of rings.

12. A method for propagating sound, comprising the steps of: - providing a radiator along a longitudinal axis and a frame surrounding the radiator so as to form a lining comprised between the radiator and the frame, the lining being defined by an inner surface of the frame and an outer surface of the radiator; - providing a magnetic circuit defining a path for the circulation of a magnetic field and comprising a fixed magnetic element connected to the basket and a movable magnetic element connected to the radiator; - generating a magnetic field in response to the electrical signal to be converted; - moving the movable magnetic element in response to the generated magnetic field so as to move the radiator along the longitudinal axis; - in response to relative movement between the radiator and the basket, a ring of plastic material coaxial with the longitudinal axis and arranged inside the liner is caused to move longitudinally rollingly on the outer surface of the radiator and the inner surface of the basket.

13. The method according to claim 12, wherein: a flange extending parallel to said longitudinal axis, extending between a first end and a second end opposite said first end and defining an outer surface of said radiator; - a peripheral edge positioned at the first end of the flange in a plane transverse to the longitudinal axis, the peripheral edge protruding from the flange towards the interior of the liner, the peripheral edge being separated from the basin frame by an air space open to the external environment.

14. The method according to claim 13, wherein: The radiator comprises a further peripheral edge positioned at the second end of the flange in a further plane transverse to the longitudinal axis, the further peripheral edge protruding towards the interior of the lining, the further peripheral edge being arranged on the flange or on the inner surface of the basin frame, the ring rolling along the longitudinal axis between the peripheral edge and the further peripheral edge.

15. The method according to any one of claims 12 to 14, wherein: The fixed magnetic element and the basin frame define a fixed structure, and the radiator and the movable magnetic element define a movable working unit, and the method comprises the following steps: - guiding the longitudinal movement of the movable working unit via a guide device, the guide device comprising an inner surface extending around a longitudinally oriented guide axis, and an outer surface extending around the guide axis and surrounding the inner surface to define a gap; - providing a spring, which is closed on itself to form a loop, which is arranged in the gap in contact with the inner and outer surfaces of the guide means, The guiding step occurs by causing the spring to roll longitudinally move on the inner and outer surfaces of the guide device in response to relative movement between the inner and outer surfaces, wherein the inner surface is connected to the fixed structure and the outer surface is connected to the movable working unit, or vice versa.

16. The method according to any one of claims 12 to 14, comprising the steps of: In response to relative movement between the radiator and the basin frame, an additional ring of elastomeric material coaxial with the longitudinal axis and arranged inside the liner is rolled longitudinally on the outer surface of the radiator and the inner surface of the basin frame, and the ring and the additional ring define a pair of rings.

Images