WO2012113281A1

WO2012113281A1 - Suspension system for moving-coil loudspeaker

Info

Publication number: WO2012113281A1
Application number: PCT/CN2012/070834
Authority: WO
Inventors: Richard Little
Original assignee: Premium Loudspeakers (Hui Zhou) Co., Ltd.
Priority date: 2011-02-25
Filing date: 2012-02-01
Publication date: 2012-08-30
Also published as: CN102075835A

Abstract

The transducer assembly is provided for the moving-coil loudspeaker, the assembly comprising a magnetic motor structure, a supporting frame, a first moving part suspension element connected to said supporting frame, a diaphragm connected to said first moving part suspension element which suspends said diaphragm from said supporting frame, a voice coil attached to said diaphragm and suspended within said magnetic motor structure, a second moving part suspension elements attached to said diaphragm, and to said supporting frame. The present invention allows for the design of shortened transducers, without the use of complex shaped motor components or additional coupler parts, and further can achieve the purpose to make the loudspeaker thinner.

Description

SUSPENSION SYSTEM FOR MOVING-COIL LOUDSPEAKER

The present application claims priority of the Chinese applications, the application no. are 201110044993.9 filed Feb 25,2010.

FIELD OF THE INVENTION

The present invention generally relates to loudspeakers and loudspeaker suspension systems, and more particularly, features a moving-coil loudspeaker transducer with two moving part suspension elements.

BACKGROUND OF THE INVENTION

As seen from Fig. 1 of speaker in prior art, mo ving-coil loudspeaker transducers are typically formed of a diaphragm 1, voice coil 3 (including voice coil windings 4) usually covered by cap 13 to prevent dust from getting inside, magnetic motor which includes first washer 8, magnetic part 9 (e.g., magnet), second washer 10, U shape section shell 11 and copper cap 12 covered said washer 8 and magnetic part 9 ,supporting frame 5,and two moving part suspension elements called a surround 6 and a spider 7. The surround 6 suspends the diaphragm 1 from the supporting frame 5. The voice coil 3 is attached to the diaphragm 1, and the spider 7 acts to suspend the voice coil 3 in the

magnetic motor

9, 10, 11, properly centered. The balance of stiffness of the surround 6 and spider 7 control the amplitude of motion of the voice coil 3 under high frequency resonant mode conditions, thus preventing undesired contact between the voice coil 3 and motor elements.

As loudspeakers are being designed to be thinner, by necessity the loudspeaker transducers are being designed to be thinner, or shorter, as well. Normal transducers are designed with the spider suspension element attached to the voice coil. The clearance requirements between the coil/spider attachment, and the motor, add height to the transducer. The clearance requirements between the diaphragm and the spider elements also add height to the transducer. These clearance requirements limit how short conventional transducer designs can be made.

Other product designs have circumvented these limitations in two fashions. In one design, as seen in the speaker of Fig. 2 , a spider coupler element 2 was introduced to the transducer design. This spider coupler 2 was attached to the diaphragm 1, to the outside of the voice coil 3. The spider 7 was attached to the supporting frame 5 and to the spider coupler 2.

In a second design, as seen in the speaker of Fig. 3, the transducer magnetic motor design was altered, with cut-outs being introduced to the outside of the motor. The spider 7 was then attached to the voice coil 3, by extending through the cut-outs in the motor.

Both of these designs allow for shorter loudspeaker transducers, by allowing the plane of the spider to be much nearer the top of the motor, or to be co-planar with the motor, than excursion requirements would otherwise allow in normally-designed moving coil transducers. However, the added parts, or re-designed parts, add complexity to the manufacturing process, and cost to the product.

SUMMARY OF THE INVENTION

In view of the foregoing, it is at least one object of the invention to provide a transducer for a mo ving-coil loudspeaker which avoids the disadvantages of the prior art. Furthermore, other objects, desirable features, and characteristics will become apparent from the description herein and the subsequent description of the preferred embodiments, and appended claims, taken in conjunction with the accompanying drawings and the background of the invention mentioned above.

At least one solution of the at least one object, other objects, desirable features, and characteristics is achieved by a moving-coil loudspeaker. In the present invention, the typical spider is deleted from the design, and replaced with a set of vertically oriented suspension elements, connected between the supporting frame and the lower surface of the diaphragm.

The moving-coil loudspeaker comprising a magnetic motor structure having a magnetic gap, a supporting frame, a first moving part suspension element connected to said supporting frame, a diaphragm having a lower surface and an upper surface, connected to said first moving part suspension element which suspends said diaphragm from said supporting frame, a voice coil attached to said diaphragm and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding, said wire winding having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween, a second moving part suspension elements attached to said lower surface of the diaphragm, and to said supporting frame.

The second moving part suspension elements are preferably vertically oriented to the lower surface of said diaphragm. Alternatively ， said second moving part suspension elements also can deviate from the true vertical orientation by up to 45 degrees .

The connected points of said supporting frame and said second moving part suspension elements preferably lie outside of said magnetic motor structure.

The distance between said diaphragm and the connected points of said supporting frame and said second moving part suspension elements is equal to or bigger than the distance between said diaphragm and the top plane of said magnetic motor structure.

The second moving part suspension elements are preferably constructed of treated fabric material, flexible rubber or flexible elastomer material, or may be constructed of a coiled metal spring or a set of metal flexures, or may be constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material and metal spring and metal flexures.

The second moving part suspension elements may also be attached to said lower surface of the diaphragm with one end, and attached to said magnetic motor structure with another end.

The second moving part suspension elements may lie outside or inside of said voice coil.

The present invention described herein replaces the spider, with vertically oriented suspension elements which are attached to the diaphragm and supporting frame. The attachment points lie outside or inside of the voice coil, and can lie outside of the outer diameter of the magnetic motor, which allows the height of the transducer to be reduced and then the loudspeaker can be made thinner, without the use of additional couplers or complex motor parts. The motor parts may also have their shape altered, so as to allow the vertically oriented suspension elements to attach to surfaces within the motor structure itself.

In accordance with these and other objects which will become apparent hereinafter, the present invention will now be described with particular reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a Cross-section view of normal transducer;

Fig. 2 shows a Cross-section view of transducer with spider coupler;

Fig. 3 shows a Cross-section view of transducer with magnetic motor structure cut-outs;

Fig. 4 shows a Cross-section view of the present invention, a transducer with vertically oriented suspension elements;

Fig. 5 illustrates a perspective view of the transducer with vertically oriented suspension elements of the present invention with supporting frame deleted from view;

Fig. 6 shows the vertical suspension elements attached to the top of a transducer motor component present outside of the cylinder of the voice coil;

Fig. 7 shows the vertical suspension elements are attached to the top of a motor component which is inside of the cylinder of the voice coil;

Fig.8 shows the vertical suspension elements passing through a non-round, non-regularly-shaped motor, and being attached to a mechanical spacer element, with the supporting frame not shown;

Fig. 9 shows the t-pole component is constructed in two parts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following detailed description is merely exemplary in nature and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.

With reference to the drawings, Fig.4 and Fig.5 depict the moving-coilloudspeaker of the present invention. The moving-coil loudspeaker generally comprises a magnetic motor structure having a magnetic gap; a supporting frame 5; a first moving part suspension element 6(e.g., a surround) connected to said supporting frame 5; a diaphragm 1 having a lower surface and an upper surface, connected to said first moving part suspension element 6 which suspends said diaphragm 1 from said supporting frame 5;a voice coil 3 attached to said diaphragm 1 and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding 4, said wire winding 4 having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween, as an alternative embodiment , said voice coil 3 may be attached to said diaphragm 1 through connector or coupler 2; a second moving part suspension elements 7 (henceforth defined as plicae) attached to said lower surface of the diaphragm 1, and to said supporting frame 5 .

The second moving part suspension elements 7 are preferably vertically oriented to the lower surface of said diaphragm 1.

The connected points of said supporting frame 5 and said second moving part suspension elements 7 preferably lie outside of said magnetic motor structure.

The distance between said diaphragm 1 and the connected points of said supporting frame 5 and said second moving part suspension elements 7 is equal to or bigger than the distance between said diaphragm 1 and the top plane of said magnetic motor structure .

The second moving part suspension elements 7 are preferably constructed of treated fabric material, flexible rubber or flexible elastomer material, or may be constructed of a coiled metal spring or a set of metal flexures, or may be constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material and metal spring and metal flexures.

In further embodiment, as seen in Fig 6, the second moving part suspension elements 7 may also be attached to said lower surface of the diaphragm 1 with one end, and attached to said

magnetic motor structure

20,21,22 with another end.

In the optional embodiment, the second moving part suspension elements 7 may lie outside or inside of said voice coil(refer to Fig 7).

The invention also provides a design of a transducer using a set of vertical suspension elements, which are attached to the lower surface of the diaphragm, in which the motor is designed to extend beyond the cylinder of the voice coil, in a non-round shape as seen from Fig. 8, but is shaped to allow the vertical suspension elements to substantially pass through the motor structure, with the lower surface of the vertical suspension element attached to a lower surface of the motor. It may be desired that there are mechanical spacers 25 placed between the lower surface of the vertical suspension elements, and the attachment surface on the motor. Said mechanical spacer elements may be placed at one or both ends of the vertical suspension elements.

In further embodiments, as shown in Fig. 9, a t-pole section 22 is provided for the motor, it is preferred to be constructed in two parts, so as to allow for the temporary removal of the pole section of the motor during the transducer assembly process.

This function of the invention is like that of normal moving-coil loudspeaker transducers. The voice coil 3 and magnetic motor structure act to convert electrical input signal into a mechanical force. This mechanical force is imparted onto the diaphragm 1, which creates an outgoing air pressure wave. Both the surround 6 and the vertical suspension elements 7 act to suspend the diaphragm 1, and thus also suspend the voice coil 3 in the motor gap.

The surround 6 and vertically oriented suspension elements 7 also control or inhibit the resonant mechanical mode in which the voice coil 3 and diaphragm 1 rotate around their center of mass, a mode which is undesirable if the voice coil comes into contact with the magnetic motor parts. The effectiveness of this control is set by: the total stiffness of the transducer suspension; the relative distribution of stiffness amongst all suspension elements; the number, size, placement, material, and geometry of the vertically oriented suspension elements; the geometry and material of the surround; and the positions at which the surround and vertically oriented suspension elements are attached to the diaphragm.

The present invention allows for the design of shortened transducers, without the use of complex shaped motor components or additional coupler parts.

The present invention has been shown and described herein in what is considered to be the most practical and preferred embodiment. It is recognized, however, that departures may be made therefrom within the scope of the invention and that obvious modifications will occur to a person skilled in the art.

Claims

A moving-coil loudspeaker, comprising:

a magnetic motor structure having a magnetic gap;

a supporting frame;

a first moving part suspension element connected to said supporting frame;

a diaphragm having a lower surface and an upper surface, connected to said first moving part suspension element which suspends said diaphragm from said supporting frame;

a voice coil attached to said diaphragm and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding, said wire winding having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween;

a second moving part suspension elements attached to said lower surface of the diaphragm, and to said supporting frame .
The moving-coil loudspeaker of claim 1 wherein said second moving part suspension elements are vertically oriented to the lower surface of said diaphragm.
The moving-coil loudspeaker of claim 2 wherein the connected points of said supporting frame and said second moving part suspension elements lie outside of said magnetic motor structure.
The moving-coil loudspeaker of claim 2 wherein the distance between said diaphragm and the connected points of said supporting frame and said second moving part suspension elements is equal to or bigger than the distance between said diaphragm and the top plane of said magnetic motor structure.
The moving-coil loudspeaker of claim 2 wherein said second moving part suspension elements lie inside of said voice coil.
The moving-coil loudspeaker of claim 1 wherein said second moving part suspension elements deviate from the true vertical orientation by up to 45 degrees.
The moving-coil loudspeaker of claim 1 wherein said motor structure has a t-pole section which is constructed in two parts, so as to allow for the temporary removal of the pole section of the motor during the transducer assembly process.
The moving-coil loudspeaker of any one of claim 1-7 wherein said second moving part suspension elements are constructed of treatedfabric material, flexible rubber or flexible elastomer material.
The moving-coil loudspeaker of any one of claim 1-7 wherein said second moving part suspension elements are constructed of a coiled metal spring or a set of metal flexures or the combination of metal spring and metal flexures.
The moving-coil loudspeaker of any one of claim 1-7 wherein said second moving part suspension elements are constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material, metal springs and metal flexures.
A moving-coil loudspeaker, comprising:

a magnetic motor structure having a magnetic gap;

a supporting frame;

a first moving part suspension element connected to said supporting frame;

a diaphragm having a lower surface and an upper surface, connected to said first moving part suspension element which suspends said diaphragm from said supporting frame;

a voice coil attached to said diaphragm and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding, said wire winding having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween;

a second moving part suspension elements attached to said lower surface of the diaphragm, and to said magnetic motor structure.
The moving-coil loudspeaker of claim 11 wherein said second moving part suspension elements are vertically oriented to the lower surface of said diaphragm.
The moving-coil loudspeaker of claim 12 wherein said second moving part suspension elements lie outside of said voice coil.
The moving-coil loudspeaker of claim 12 wherein said second moving part suspension elements lie inside of said voice coil.
The moving-coil loudspeaker of claim 12 wherein the distance between said diaphragm and the connected points of said magnetic motor structure and said second moving part suspension elements is equal to or bigger than the distance between said diaphragm and the top plane of said magnetic motor structure.
The moving-coil loudspeaker of claim 11 wherein said motor structure has a t-pole section which is constructed in two parts, so as to allow for the temporary removal of the pole section of the motor during the transducer assembly process.
The moving-coil loudspeaker of any one of claim 11-16 wherein said second moving part suspension elements are constructed of treated fabric material, flexible rubber or flexible elastomer material.
The moving-coil loudspeaker of any one of claim 11-16 wherein said second moving part suspension elements are constructed of a coiled metal spring or a set of metal flexures or the combination of metal spring and metal flexures.
The moving-coil loudspeaker of any one of claim 11-16 wherein said second moving part suspension elements are constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material, metal springs and metal flexures.
The moving-coil loudspeaker of claim 11 wherein said second moving part suspension elements deviate from the true vertical orientation by up to 45 degrees.
A moving-coil loudspeaker, comprising:

a magnetic motor structure having a magnetic gap;

a supporting frame;

a first moving part suspension element connected to said supporting frame;

a diaphragm having a lower surface and an upper surface, connected to said first moving part suspension element which suspends said diaphragm from said supporting frame;

a voice coil attached to said diaphragm and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding, said wire winding having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween;

a set of mechanical spacer elements, attached to a surface on the magnetic motor structure;

a second moving part suspension elements attached to said lower surface of the diaphragm, and to said mechanical spacer elements.
The moving-coil loudspeaker of claim 21 wherein said second moving part suspension elements are vertically oriented to the lower surface of said diaphragm.
The moving-coil loudspeaker of claim 21 wherein said second moving part suspension elements deviate from the true vertical orientation by up to 45 degrees.
The moving-coil loudspeaker of any one of claim 22-23 wherein said second moving part suspension elements are constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material, metal springs and metal flexures.
The moving-coil loudspeaker of claim 21 wherein said motor structure has a t-pole section which is constructed in two parts, so as to allow for the temporary removal of the pole section of the motor during the transducer assembly process.
A moving-coil loudspeaker, comprising:

a magnetic motor structure having a magnetic gap;

a supporting frame;

a first moving part suspension element connected to said supporting frame;

a diaphragm having a lower surface and an upper surface, connected to said first moving part suspension element which suspends said diaphragm from said supporting frame;

a voice coil attached to said diaphragm and suspended at least partially within said magnetic gap of said magnetic motor structure, including a former having an inner surface which carries a wire winding, said wire winding having an uppermost winding, a lowermost winding and a number of intermediate windings therebetween;

a second moving part suspension elements attached to said lower surface of the diaphragm, and to a surface within the motor structure;

a non-circular shape to the magnetic motor structure which allows the second moving part suspension elements to be attached to the motor structure on an interior surface of the motor structure, with the motor structure extending outwards beyond the placement location of the second moving part suspension elements.
The moving-coil loudspeaker of claim 26 wherein said second moving part suspension elements are vertically oriented to the lower surface of said diaphragm.
The moving-coil loudspeaker of claim 26 wherein said second moving part suspension elements deviate from the true vertical orientation by up to 45 degrees.
The moving-coil loudspeaker of any one of claim 26-28 wherein said second moving part suspension elements are constructed of any combination of treated fabric material, flexible rubber and flexible elastomer material, metal springs and metal flexures.
The moving-coil loudspeaker of claim 26 wherein said motor structure has a t-pole section which is constructed in two parts, so as to allow for the temporary removal of the pole section of the motor during the transducer assembly process.
The moving-coil loudspeaker of claim 26 wherein said magnetic motor structure has attached mechanical spacer elements, placed between an interior surface of the magnetic motor structure and the second moving part suspension elements .