JP3186540B2 - Mass excited acoustic device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates generally to electromagnetic transducers and, more particularly, to a mass excited acoustic device used to reproduce the sound of an audible voice message signal using a tuned sound board.
ustic device).

[0002]

BACKGROUND OF THE INVENTION Portable radiotelephones, such as pocket-sized cellular telephones and second-generation (CT2) cordless telephones, are becoming increasingly popular, especially due to the reduced size and price of portable radiotelephones. I am doing it.
Current cellular radio telephones utilize an audible ringing signal to notify the cellular radio telephone user of an incoming call. However, the use of audible ringing signals has drawbacks. One of these disadvantages
First, when the portable radiotelephone is carried in a pocket, the audible call signal becomes difficult to hear, and the user of the portable radiotelephone may miss the call. In addition, there are many places in public business, such as theaters and restaurants, where the use of devices that generate audible call signals is prohibited, as the audible call signals may bother other customers there. .

[0003] In order to generate a vibration warning signal, a tactile, ie, silent, warning device may be used in a portable communication device such as a pager. An advanced haptic warning device among portable communication devices according to the prior art is an eccentric weight vibrator driven by a motor.
r). Such motor-driven eccentric weight vibrators are used in certain types of portable communication devices, but because of the large space required for mounting the motor, their use in current portable radio telephones is Not very welcome.
Also, most portable radios have a very limited battery life, so using a motor-driven eccentric weight transducer that requires a significant amount of current to operate makes such portable radios available Operating time is further reduced. Transducers that generate both haptic and audio outputs have been filed by McKee et al. On July 6, 1992, and entitled "Stabilized Electromagnetic Resonant Armature."
US Patent Application No. 07 /, entitled "Tactile Vibrator"
909,261. While this transducer can generate tactile and audio output in portable communication devices such as portable radiotelephones, conventional mounting methods that can be used provide sufficiently low frequency, or bass, response. Generating audio frequency responses has generally been unsuccessful.

[0004] Therefore, there is a need for improved means for mounting a transducer that can be used in a portable radiotelephone or other sound generating device. The improved mounting means is to optimize the soundboard with respect to the resonance frequency, thereby driving the soundboard directly and generating an enhanced bass response,
It must also be compatible with any of a number of transducers.

[0005]

SUMMARY OF THE INVENTION In a preferred embodiment of the present invention, a mass excited acoustic device comprises a sound board having a predetermined resonant frequency for coupling kinetic energy to a user of the device.
A pedestal constituted by the platform and a leg disposed opposite thereto and coupled to the sound board and having a size substantially smaller than the platform; and the platform around an axis extending centrally between the platform and the leg. Transducer that converts the electrical input signal into kinetic energy generated in a direction parallel to the axis, whereby the kinetic energy is transmitted through the legs without substantially altering the resonance frequency of the sound board. A transducer provided to the board.

In an alternative embodiment of the present invention, the mass excited acoustic device comprises a sound board having a predetermined resonant frequency for coupling kinetic energy to a user of the device; a platform and a sound board disposed opposite the sound board. A pedestal formed by legs that are substantially smaller in size than the platform; coupled to the platform about an axis extending centrally between the platform and the legs to function an alternating electromagnetic field in response to an audio input signal. An armature comprising: an electromagnetic driver; and an upper and lower substantially parallel planar suspension members coupled to the electromagnetic driver, each planar suspension member being regularly spaced about a central planar region within a planar peripheral region. An armature constituted by a plurality of independent planar circular non-linear spring members arranged, and an upper portion around a central planar region and A magnetic kinetic mass suspended between two planar suspension members, wherein the magnetic kinetic mass is coupled to an electromagnetic field and alternately moves the magnetic kinetic mass in response to the electromagnetic kinetic mass; And a magnetic kinematic mass that is converted to kinetic energy generated in a direction parallel to the axis through an electromagnetic driver, thereby substantially increasing the resonance frequency of the sound board. Without change, the kinetic energy is transmitted to the sound board through the legs.

In a first aspect of the present invention, a sound transmission system includes a sound source for generating a sound input signal; processing means for processing the sound input signal to drive a transducer; and a kinetic energy transferred to the sound source. A sound board having a predetermined resonance frequency to be coupled to the user, a pedestal constituted by a platform and a leg disposed opposite to and coupled to the sound board and having substantially smaller dimensions than the platform; and One or more mass excitations coupled to the platform about a centrally extending axis between the legs and a transducer for converting an audio input signal into kinetic energy generated in a direction parallel to the axis. An acoustic device that substantially changes the resonance frequency of the soundboard. Kinetic energy mass excited acoustic device delivered to the soundboard through legs without;
And a housing that is coupled to the sound board and houses the pedestal and the transducer.

In a second aspect of the present invention, a personal communication device includes a housing having a portion forming a sound board having a predetermined resonance frequency; an encoded housing contained within and transmitted to the housing. A receiver for receiving and detecting the detected message signal; processing means for processing the detected encoded message signal; and coupled to and coupled to the platform about an axis extending centrally between the platform and the leg. An electromagnetic driver that produces an alternating electromagnetic field in response to the processed encoded message signal; and an armature including an upper and lower substantially parallel planar suspension member coupled to the electromagnetic driver. By a plurality of independent planar circular non-linear spring members, each of which is regularly arranged around a central planar region within the planar peripheral region And armature to be made, is suspended between upper and lower planar suspension members to the planar area around the central,
A magnetic kinematic mass coupled to an electromagnetic field to alternately move the magnetic kinematic mass in response thereto, wherein the motion of the magnetic kinematic mass is parallel to an axis via a planar non-linear spring member and an electromagnetic driver. A transducer constituted by a magnetic kinetic mass which is converted into kinetic energy generated in a direction.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a top view of a planar non-linear spring member 100 utilized in a mass excited acoustic device according to a preferred embodiment of the present invention. Planar nonlinear spring member 100
Is, in one embodiment, a circular inner diameter 104 and a circular outer diameter 10.
6 and, in an improved embodiment, has a planar substantially circular spring member 102 having an elliptical inner diameter 104 and a circular outer diameter 106 as shown in FIG.

[0010] The planar non-linear spring member 100 shown in FIG.
Improved embodiment provides a spring member having a non-uniform width, wherein the width "2X" is the widest and substantially circular planar spring member 1 in the region up to the end restraint 108.
In the vicinity of the intermediate point 114 of 02, the width is reduced to the width “X”. The circular spring member 102 has a substantially uniform width “2.5
Through the end constraining portion 108 having “7X”, it is connected to the central flat region 110 and the flat peripheral portion 112.

FIG. 2 is a sectional view taken along the line 1-1 in FIG. As shown, the thickness of the improved planar nonlinear spring member 100 is, for example, “.43X”.
It should be understood that the dimensions and thickness of the planar non-linear spring member 100 affect the resonance frequency at which the dual mode oscillator resonates and can be changed to accommodate different operating frequencies.

FIG. 3 shows a dual mode transducer 3.
00 is a top view (with the circuit board 306 removed) of FIG. FIG. 3 illustrates a coil mold 302, which is, for example, about 0.7 inches (17.78 mm) in diameter and serves as an electromagnetic driver that generates an alternating magnetic field in response to an excitation signal, such as an audio input signal. The electromagnetic coil 304 (FIG. 4) is housed. The coil type 302 has terminals 32 for making an electrical connection to the coil 304 such as a 30% glass-filled liquid crystal polymer.
It is made using a conventional two-stage injection molding method using a plastic material that completely encloses the coil 304 except for 6. It should be understood that other plastic materials can be utilized as well for the coil mold 302. The coil mold 302 defines two planar peripheral seating surfaces 330 (FIG. 4) around the planar perimeter 308, on which two planar suspension members 310 are supported, which further comprises eight continuous And a boss 332 that has been molded. These bosses are subjected to a staking process using heat or ultrasonic waves.
s) is used to orient and secure the planar spring member 310 to the coil mold 302.

Each of the two planar suspension members 310
It comprises four independent planar non-linear spring members 312 regularly arranged around a central planar region 314. The central region 314 is used to position the movable mass 316 and secure it to the two planar suspension members 310, again using a caulking process. Planar nonlinear spring member 312
Is defined as having a circular outer periphery and a circular or elliptical inner periphery, as illustrated in FIG. 1 above. The planar suspension member 310 is made from a sheet metal such as Sandvik (TM) 7C27M02 stainless martensite chromium steel alloy with molybdenum or CH900 precipitation hardened stainless steel heat treated with 17-7PH. Please understand that other materials can be used as well. The thickness of the metal sheet is preferably 0.002 inches (0.0508 mm)
And the planar suspension member is preferably formed by chemical etching or machining. The movable mass 316 is
It is made by the conventional die casting method using Zamak3 zinc die casting alloy, but it should be understood that other materials can be used.

The arrangement of the components of the dual mode transducer 300 is such that the moving mass 316 can be displaced up and down in a direction perpendicular to the two planar suspension members 310, and in response to this displacement an independent planar nonlinear This displacement is limited by the restoring force provided by the spring member 312. The movable mass portion 316 is formed so as to penetrate the independent planar non-linear spring member 312 during the movement of the movable mass portion 316 and form a groove 318 around which the movable mass portion 316 extends, as described later. , Dual mode
The transducer 300 is better than the case without the groove 318.
Can also provide a large output. The driving force of the movable mass section 316 is generated by four radially polarized permanent magnets 320 attached to the movable mass section 316 and magnetically coupled to the electromagnetic coil 304. The permanent magnet 320
Produced using samarium-cobalt with a maximum energy generation of 28-33 and having an NS radiation orientation of 8K-1
Generates a coercive force of 1K Oersted. Two planar suspension members 310, a movable mass 316 and four permanent magnets 3
20 constitute the resonant armature system for the dual mode transducer 300.

The detail shown in FIG. 3 further includes a flat peripheral portion 308 of the upper flat suspension member 310 which projects in a direction perpendicular to the respective surfaces (upper and lower surfaces) of the coil mold 302.
There are four radial projections 322 that are in compression engagement with the boss. The planar suspension member 310 is attached to the surface of the coil mold 302 using bosses 332 located on each side of each protrusion 322 .
Be killed. The boss 332 is caulked using heat or ultrasonic waves, and the planar suspension member 310 is fixed to the planar peripheral portion 308 of the coil mold 302 . The protrusions 322 help prevent audible (high frequency) parasitic vibrations during operation of the dual mode transducer 300 .

Referring to FIG. 4, the cross-section of the dual mode transducer of FIG.
24 are clearly shown. The gap 324 is formed by the movable mass 31
6 (partially shown) so that the movable mass 316 can move in a direction perpendicular to the plane of the two planar suspension members 310. During operation, the electromagnetic coil 3
04 is a resonance armature system 3 constituted by a movable mass 316, a magnetic member 320, and a planar suspension member 310.
An alternating magnetic field polarized in a direction parallel to axis 342 through the center of 36 is generated at a frequency substantially the same as the fundamental resonance frequency of resonant armature system 336. The alternating magnetic field is generated when the drive signal is coupled to the electromagnetic coil 304,
The drive signal is preferably a swept low frequency drive signal for generating a tactile alert or an audible drive signal for generating an audible response. The generated alternating magnetic field is magnetically coupled to four permanent magnets 320 that are physically coupled to the moving mass 316. This magnetic coupling creates an alternating excitation force on the resonant armature system 336, causing the resonant armature system 336 to oscillate in a displacement direction parallel to the axis 342 when a swept low frequency drive signal or an audible drive signal is provided. When the dual-mode transducer 300 is installed in a device such as a personal portable radiotelephone such that the axis 342 is oriented perpendicular to the user's body, less power is required than for a conventional transducer. The advantage is that a strong haptic response is generated when input to the dual mode transducer 300. Such an improvement in efficiency is obtained because dual mode transducer 300 overcomes many of the power dissipation characteristics associated with early transducer designs.

The preferred embodiment according to the present invention is a permanent magnet 3
Although an electromagnetic coil 304 that interacts with 20 to generate an alternating exciting force is used, the alternating exciting force can be similarly generated using other means such as a piezoelectric means.

FIG. 5 is a graph comparing the displacement and fundamental frequency response of a dual mode transducer and an equivalent linear resonant oscillator system. Frequency response curve 502
Is, for example,. Driven at an excitation voltage of 9 volts, and in response, at a center drive frequency of 85 Hz. Shown for a linear resonant oscillator system producing a peak displacement of 035 inches (.89 mm), corresponding to a shock power of 27 g's calculated from the following equation:

[0019]

G's = 0.10235 (d) (f) ^{3 where} g is the shock output generated by the system, d is the displacement of the oscillating mass, and f is the drive frequency.

As shown by the frequency response curve 502, the linear resonant oscillator system has a high Q and the shock output falls off rapidly on both sides of the peak center frequency. As a result, great care must be taken to control the drive frequency to match the peak center frequency to maximize the shock output. Fluctuations in the drive frequency, and more specifically, fluctuations in the response of the linear resonant oscillator system due to manufacturing errors, can significantly reduce the resulting shock output.

In contrast, dual-mode transducers are hardened spring-type resonance systems that can provide high shock output over a wide range of drive frequencies 504. Same as above. The shock output for a hardened spring resonance system when driven with an excitation voltage of 9 volts is:
Compare to the linear oscillator system in the following table: Reference number Impact displacement Drive frequency (g's) (in./mm) (Hz) 506 12 0.020 /. 51 85 508 24 0.025 /. 64 95 510 45 0.035 /. Above the 89 115 point 512, the shock output of the dual mode transducer drops off rapidly. This will be described later.
As can be seen from the above table, it is possible to obtain a much higher impact response as compared with the linear resonance oscillator system without restricting the control of the center drive frequency.

FIG. 6 is a graph 600 illustrating the impact output as a function of frequency for a dual mode transducer utilizing a non-linear stiffened spring resonance system. Unlike linear resonant oscillator systems, which require meticulously controlled drive frequencies to maximize shock output, dual mode transducers utilizing a non-linear stiffened spring-type resonance system preferably have low shock A first drive frequency that produces an output 602 and a second drive frequency that produces a high shock output 604
It is driven by a sweep drive frequency operating between the drive frequency. The high shock output 604 is preferably selected such that a stable operating state substantially corresponds to a maximum drive frequency of only one. As can be seen from FIG. 6, when the drive frequency is set to the value required to obtain the shock output 610, two stable operating states 604, 610 are possible. And as the drive frequency increases from there, three stable states are possible, as indicated, for example, by the shock outputs 606, 608, 612. When using the dual mode transducer 300 as a tactile warning device,
It can be seen that only an impact response on curve 600 between operating states 602 and 604 is desired. This is because the shock output is reliably maximized in this frequency range. As explained below, the shock response on curve 600 beyond operating state 612 is suitable for providing an audible response. In addition, the response to audio input frequencies beyond operating state 612 is a dual mode transducer 3
Enhanced by a 00 harmonic response.

FIG. 7 is a front elevational view of a personal portable radiotelephone 700 utilizing the dual mode transducer 300 shown in FIGS. Silver link 2000 Personal Teleph from Motorola, Schaumburg, Illinois
A personal radiotelephone 700, such as one, has a housing 702 containing transceiver circuitry used to provide two-way radio frequency communication with other personal radiotelephones or telephones coupled to conventional telephone networks. Is included. A keypad 706 coupled to the housing 702 allows a user to enter information such as a telephone number or password, and provides a display 708 for displaying the entered telephone number or password to be dialed. Microphone 710 is located within a hinged housing member 704 and dual mode transducer 300 is mounted on top 716 of housing 702. The housing portion identified as 714 functions as a sound board, as described below, and is shown cut away to show dual mode transducer 300. Dual mode transducer 300
Functions as a tactile warning device in one mode and as a sound range transducer in a second mode.
Transmission and reception of the bidirectional wireless communication signal are performed by the antenna 718.

FIG. 8 is a cross-sectional view taken along line 3-3 of FIG.
One method for mounting the transducer 300 is shown. The sound board 714 is constructed using conventional injection molding and thermoset plastic materials.
6 are integrally molded. A ring 852 having a circular perimeter is formed continuously on the underside of the soundboard 714 and is used to mount the dual mode transducer 300 as shown. Duplex mode
Transducer 300 is provided on the periphery 85 of coil shape 308.
It is attached to ring 852 at 6 and is preferably held in place using an adhesive such as cyanoacrylate or epoxy adhesive. On the front of the sound board 714 is a depression, which partially identifies the position of the dual mode transducer 300 and contributes to the sound board compliance. This will be described later. There is no sound exit hole such as an electromagnetic speaker required for the conventional acoustic transducer. The sound board 714 has a uniform thickness as a whole and is tapered so as to be thinner at the peripheral edge 864.
The tapered shape contributes to the compliance of the sound board 714 and causes the sound board 714 to resonate. As the magnetic kinematic masses 316, 320 move, the motion of the magnetic kinematic masses is transformed into haptic or acoustic energy via a planar non-linear spring member coupled to an electromagnetic driver, which is further transformed via a circular ring 852 into a sound board 714.
To join. The sound board 714 functions as an earpiece that transmits tactile or acoustic energy to the user. When the housing contacts the user's ear, acoustic energy is first transmitted by bone conduction. This will be described later in detail.

As described above, the resonance of the sound board 714 is performed by the compliance of the sound board. Note that the soundboard compliance is controlled by the overall dimensions of the soundboard, shown as a circular soundboard 714, and the stiffness of the annular soundboard area 860. The kinetic energy generated by the dual mode transducer 300 is
It couples to a sound board 714 around a central sound board area 862 and to an annular sound board area 860. It should be understood that many devices have a limited surface area of the housing on which the sound board is provided, such as the portable wireless telephone device shown in FIG. As a result, the annular soundboard area 860 is relatively narrower than the entire active area of the soundboard 714, so that the soundboard resonance is relatively higher as shown in FIG. 10 described below.

FIG. 9 shows a dual mode transducer 3
FIG. 8 is an electrical block diagram of the portable wireless telephone shown in FIG. 7 utilizing 00. Voice messages are transmitted over a radio frequency channel and communicate over the CT2 (2nd generation cordless) common air interface protocol (CT2 Common Air Interface).
ce protocol). In this protocol, audio signals are processed using adaptive differential pulse code modulation and transmitted in a time division multiplexed manner. As shown in FIG. 9, the transmitted voice message signal is captured by antenna 902 and processed by radio frequency transceiver 904 into a recovered voice message signal with time division multiplexed information. Processing means 936 comprising a time division multiplexer 906, an adaptive differential pulse code modulator / demodulator 908 and a coder decoder (codec) 910 processes the detected voice message signal. This will be described later. The time-division multiplexed voice message signal is recovered from the received channel information in the form of a 4-bit adaptive differential pulse-modulated signal processed by an adaptive activation pulse code modulator / demodulator 908 to provide an 8-bit pulse code modulation. The output is processed by a time division multiplexer 906. The 8-bit pulse code modulated signal is coupled to the input of a coder decoder 910, which converts the pulse code modulated signal to an audio signal (au).
It is converted to an analog signal representing a dio ringer signal, followed by the original audible voice message. The audio signal signal is coupled to and detected by a call detector circuit, a function performed within microcontroller 1912. When an audio signal signal is detected, a ringer enable signal is sent to the microcontroller 912.
, Which is coupled to a swept low frequency signal generator 916 that generates a swept audio lower frequency signal. The swept sub-audible frequency signal is preferably repeatedly swept at predetermined time intervals, such as at 550 millisecond intervals, while the audio signal device signal is received. The frequency range of the swept sub-audible frequency signal is a function of the dual mode transducer design and typically covers a frequency range of 70-110 Hz to 105-190 Hz. The frequency range in which the tactile stimulus is most sensitive to the user of the device is selected.

The response of dual mode transducer 300 to a swept sub-audible frequency signal is shown in FIG. This is a dual mode transducer 300 mounted using conventional mounting methods within a portable radiotelephone housing 702.
5 is a graph showing the overall frequency response of the. As the dual mode transducer 300 is swept in the sub-audible frequency range, a prominent response 1002 is generated at the fundamental resonance frequency of the dual mode transducer 300, imparting a large amount of tactile energy to the portable transceiver housing 702. As the frequency input increases, the haptic energy output drops sharply, as described in FIG. A relatively constant audible output 1004 is generated, allowing the dual mode transducer 300 to function as an audible transducer over the received voice message frequency range. The output 1006 of the dual mode transducer 300 peaks again at a relatively high frequency of 6 kHz, which is the resonance frequency of the sound board 714 in the example of FIG. This is due to the relatively low compliance of the annular soundboard area 860, which leads to a relatively high soundboard stiffness, as described above.
As seen in FIG. 10, audible distortion 1008 remains relatively constant and low over most of the audible or voice message frequency range. As expected, the audible distortion peak 1010 increases at the fundamental resonance frequency of the dual mode transducer 300, but the peak caused by the secondary sound board 714 and / or the dual mode transducer 300 response is smaller.

Returning to FIG. 9, to control the haptic response of dual mode transducer 300, processing means 936
A high-pass filter 914 that is part of the received voice path is placed in the received voice path and significantly attenuates the frequency received in the voice message at the fundamental resonance frequency of the dual mode transducer. The filtered audible message signal is coupled to a dual-mode driver circuit, which amplifies the audible message signal and couples it to the dual-mode transducer.

Microphone 920, gain adjustment circuit 922
And the sidetone adjustment circuit 924 allows the user of the portable transceiver to convey audible messages in a manner well known in the art. With the received audible signal, the output of the sidetone conditioning circuit 924 is coupled to the dual mode transducer 300 via a high pass filter 914 to prevent unwanted tactile responses by the dual mode transducer 300. The audible message generated by microphone 920 is processed through a coder decoder 910, an adaptive differential pulse code modulator 908, a time division multiplexer 906, and a transmitter portion of transceiver 904, in a manner well known in the art. A keyboard 926 for entering the called party's telephone number or looking up the stored telephone number
Is provided. The input of the telephone number is processed by the microcontroller 912. Microcontroller 91
2 couples the telephone number information to a display driver 928 to provide a display 930 such as a liquid crystal display.
Display above. The code memory 932 stores the address of the portable transceiver and the PIN number. These are used by the microcontroller to selectively connect the portable transceiver 900 upon receipt of a matching selective call address signal or to communicate with the telephone base station in a manner well known in the art. Make it possible.

The received call signal is decoded to generate either a preset audible call or chirp signal or a ramp-up audible call or chirp signal to generate an audible signal for notifying the user of an incoming call. Unlike conventional portable radiotelephone handsets that generate, portable transceivers using dual mode transducer 300 preferably generate haptic alerts. Tactile alerts indicate a newly received call or "call-waitin
g) "when the call alert is generated, the alert signal is unobtrusive, i.e., if the portable transceiver is placed on the user's ear during a conversation during the" call waiting "alert, the user may be close to the user. This has the advantage that the user is not disturbed and the user is not exposed to loud audible alarms.

FIG. 11 is a cross-sectional view of a mass excited acoustic device 1100 according to a preferred embodiment of the present invention. The mass excited acoustic device comprises a sound board 1102 having a predetermined resonant frequency used to couple kinetic energy generated by the transducer 1124 to a user of the device. A pedestal 1104 that operates as a resonance bridge is coupled to the sound board 1102. This will be described later. The pedestal 1104 comprises a platform 1106 and legs 1108, which are formed continuously on the back of the sound board 1102 using conventional injection molding and thermoset plastic materials. A ring 1118 having a circular perimeter is formed continuous with the surface of the platform 1106 and is used to mount a transducer 1124, such as the dual mode transducer 300. When a dual mode transducer 300 is utilized, the dual mode transducer 300 is attached to the ring 1118 at the periphery 1120 of the coil form 308, preferably using an adhesive such as a cyanoacrylate or epoxy adhesive. It is held in place. There is a depression in the front of the sound board 1102 and there is no audio exit hole. Sound board 11
02 has a radially thinner thickness to the substantially thinner thickness of the periphery 1114. In the preferred embodiment of the present invention, the thickness of the sound board is. 125 inches (3.2
mm) at the sound board periphery 1114. 035
It is as thin as inches (0.9 mm) and produces a soundboard resonance frequency of about 2 kilohertz. The actual shape and dimensions of the soundboard can be empirically adjusted to set any soundboard resonance frequency commensurate with the overall area of the soundboard. Adjust the soundboard resonance of the mass excited acoustic device to provide low frequency resonance,
By utilizing a transducer that provides a low frequency response, the mass excited acoustic device can be optimized to provide an enhanced bass response as desired with high quality audio headphones. This will be described later.

In the preferred embodiment of the present invention, the legs 1
106 is the diameter. 145 inches (3.7 mm), which is the .1 700 inches (17.8m
m), which is substantially smaller than the 1.8 inch (45.5) of the circular sound board 1102 as shown in FIG.
7 mm). It should be understood that other sound board shapes such as oval shapes can be used as well. Regarding the dimensions of the sound board mentioned above,
The area of the leg 1108 is equal to the central sound board area 86.
2 is 15% of the sound board area, compared to the conventional mounting method shown in FIG. 8 percent. As a result, the soundboard compliance and the actual resonance frequency are largely determined solely by the soundboard design and the soundboard compliance between the central soundboard area 1112 and the soundboard perimeter 1114, and by the actual mass of the transducer and platform 1104. The degree to be decided is small. Also, the kinetic energy generated by the transducer is transmitted to the sound board 1102 through the legs 1108 without substantially changing the resonance frequency of the sound board 1102.

A sound board with a small overall sound board area as described for portable radiotelephone 700 is shown in FIG. 8 since the resonant frequency of sound board 1102 is not significantly affected by the mounting of transducer 1124. Can be designed to enhance bass response compared to a sound board. FIG.
Utilizes a dual mode transducer 300
When built into the housing of the portable transceiver 700,
4 is a graph illustrating the frequency response of a mass excited acoustic device 1100 that provides such enhanced bass response according to a preferred embodiment of the present invention. Dual mode transducer 3
As 00 is swept in the sub-audible frequency range, a prominent response 1202 is generated at the fundamental resonant frequency of the transducer 300 as described above, imparting significant tactile energy to the portable transceiver housing 702. As the frequency input increases, the haptic energy output drops sharply, as described above in FIG. Relatively constant audible output 1
204 are generated to provide dual mode transducer 3
00 can function as an audible transducer in the received voice message frequency range. Duplex mode
The output 1206 of the transducer 300 peaks again at a frequency as low as 2 kilohertz, as shown in the example of FIG. 12, and as described above, the sound board region 1110 compliance is greatly improved due to the significantly improved compliance. The resonance frequency of the board 714 is greatly reduced, which makes the sound board much less rigid and lowers the resonance frequency. As can be seen in FIG. 12, the audible distortion 1208 remains relatively constant and low over most of the audible or voice message frequency range. As would be expected, the audible distortion 1210 will have a large peak at the fundamental resonance frequency of the dual mode transducer 300, and a smaller peak caused by the response of the secondary sound board 1102 and / or the dual mode transducer 300.

In summary, unlike the transducer mounting method shown and described in FIG. 8, the kinetic energy generated by the transducer 1124 is transmitted via the platform 1106 and the legs 1108 around which the transducer is mounted. The sound is transmitted to the sound board 1102 in a direction parallel to an axis 1116 extending centrally between the leg 1106 and the leg 1108. Kinetic energy is transmitted to the soundboard via the legs without substantially altering the resonance frequency of the soundboard, but only slightly, except that the soundboard compliance is induced by the actual transducer mass. This is because it only changes. Although the above description describes a mass excited acoustic device utilizing a dual mode transducer 300, it should be understood that other types of transducers, such as inertial sound transducers, may be utilized as well.

FIG. 13 illustrates a headphone system 1300 that provides enhanced bass response as described above utilizing a mass excited acoustic device 1100 according to a preferred embodiment of the present invention.
It is an electric block diagram of. Headphone system 130
0 is a housing 130 that houses the pedestal 1104 and the transducer 1124 of the mass-excited acoustic device 1100.
4 may have a single pair of headphones 1302 or for stereo operation.
Headphones 1302 are coupled to headband 1306 so that headphones 1302 can be worn around the user's head. A soft wearing cushion 1308 made of foam rubber or the like can be added to the mass-excited acoustic device to improve comfort when wearing headphones.

Each headphone 1302 is connected to a stereo audio amplifier 13 via a conductive cable or wire 1310.
12 is coupled to an audio output device. Audio amplifier 13
12 is provided by a sound source 1314. Sound source 1314 can be a broadcast receiver such as an AM / FM receiver that receives a broadcast signal at antenna 1316. A user control unit such as a control unit 1318 for selecting and tuning a channel and a control unit 1320 for controlling the volume of an audio program are provided, and other control units (not shown) well known in the art are provided. .
The sound source 1314 may be a cassette tape player / recorder, a CD disk player, or any other commonly known sound source that is available, portable, and accepts external headphones. Audio output from sound source 1314 is coupled to audio amplifier 1312 through high pass filter 1322. The high-pass filter 1322 has a dual mode
It is used to reject frequencies that would normally excite the transducer 300 into a vibration mode so that only audio programming is available from the headphones 1302.

The paging receiver 1324 is connected to headphones
In addition to the system 1300, further highly desirable features can be obtained. One such function is to notify the user of the page received while the user is listening to the audio program. The paging signal is received by an antenna 1326 and a paging receiver 132
4 in a manner well known in the art. When the address is received by paging receiver 1324, a swept low frequency alert signal is generated, as described above. The warning signal is usually a synthesizing circuit 133 for summing analog signals.
2 and is synthesized with the program voice. The aggregated audio program and alert signal are processed by the audio amplifier 1312 and sent to the dual mode transducer, resulting in an audio program and a vibration alert at the same time. Following the generation of the alert signal, the paging receiver 1324
Is a mute signal 1334 for reducing the volume of the audio program
Occurs. The received voice message is then coupled to a high pass filter 1322 via a combining circuit 1330. The received voice message is passed through a high-pass filter 132.
2 to eliminate frequencies that produce unwanted vibrational responses. The resulting filtered voice message is processed as described above, and the user can listen to the received voice message.

FIG. 14 is a signaling diagram illustrating the operation of a mass excited acoustic device in accordance with the preferred and alternative embodiments of the present invention. The following description is with reference to FIG.
It should be understood that the operations described also apply to the headphone system of FIG. Paging receiver 934
Can be coupled to the microcontroller 912 to provide an indication of a "call waiting" message. Once set up with the paging receiver 934, the user of the portable wireless telephone handset 900 can make a telephone call as shown in FIG. Ongoing phone call 1402
During the period, an address 1404 identifying the portable radiotelephone handset 900 and a numeric data message identifying the telephone number of the "call waiting" caller are transmitted to the paging receiver 9.
34 can receive. The address and data messages are processed in a manner well known to those skilled in the art to generate a warning enable signal 938 and a received data signal 940. The warning enable signal 938 is processed by the microcontroller 912, resulting in a signal enable signal, which is coupled to the swept frequency generator 916. This generator 916 generates the swept audible lower frequency signal 1408 as described above. The swept audible lower frequency signal 1408 is coupled to the dual mode driver 918 while the telephone call 1402 is in progress, resulting in a haptic alert being issued to the user as well as the voice of the ongoing telephone call. Alerts you of a "waiting" call. Since the "call waiting" alert is tactile, controlling the amplitude of the alert signal is not as critical as would be required if an audible alert signal was issued. The audible alert has the further advantage that the haptic alert signal can be issued simultaneously with the ongoing telephone call, while the audible alert disturbs the ongoing telephone call. When the telephone call ends, the numerical data transmitted by the received data signal can be processed by the microcontroller 912, and the received telephone number is displayed on the display 93.
0 can be displayed. The keyboard 926 can be used to automatically dial the received telephone number in a manner well known in the art.

In summary, a mass-excited acoustic device has been described that offers several other advantages over conventional devices that utilize a transducer coupled to a sound board.
The resonance frequency of the sound board can be set, and as described above, interaction with the resonance frequency when coupled to the transducer is minimized. Small area sound boards can be designed to have enhanced bass response. The mass-excited acoustic device is compatible with many portable devices and has no holes in the sound board, so that it can be used for devices requiring high waterproofness. As described above, utilizing a dual mode transducer in a mass excited acoustic device allows audio programming to be played simultaneously with a haptic alert. Providing headphones using a mass-excited acoustic device can achieve excellent low-frequency response and a wide voice bandwidth.

[Brief description of the drawings]

FIG. 1 is a top view of a planar non-linear spring member utilized in a mass excited acoustic device according to a preferred embodiment of the present invention.

FIG. 2 is a sectional view taken along a straight line 1-1 in FIG.

FIG. 3 is a top plan view of a dual mode transducer utilized in a mass excited acoustic device according to a preferred embodiment of the present invention.

FIG. 4 shows the dual mode transducer of FIG.
It is sectional drawing cut | disconnected by -2.

FIG. 5 is a graph comparing the fundamental frequency response and amplitude of a linear resonant oscillator system and a dual mode transducer.

FIG. 6 is a graph showing impact power as a function of frequency for a dual mode transducer utilizing a hardened spring resonance system.

FIG. 7 is a front elevational view of a personal portable radiotelephone utilizing the dual mode transducer of FIGS. 3 and 4;

8 is a cross-sectional view taken along line 3-3 of FIG. 7 illustrating one method of mounting a dual mode transducer in a portable radiotelephone housing.

FIG. 9 is an electrical schematic diagram of a personal portable radiotelephone utilizing the dual mode transducer of FIGS. 3 and 4.

FIG. 10 is a graph showing the frequency response of a dual mode transducer according to the mounting method of FIG.

FIG. 11 is a cross-sectional view of a mass excitation acoustic device according to a preferred embodiment of the present invention.

FIG. 12 is a graph showing a frequency response of the mass excited acoustic device according to the preferred embodiment of the present invention.

FIG. 13 is an electrical block diagram of an alternative embodiment of the present invention, a headphone system utilizing a mass excited acoustic device with enhanced bass response.

FIG. 14 is a signal diagram showing the operation of the mass excited acoustic device according to the preferred embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1100 Mass excitation acoustic device 1102 Sound board 1104 Pedestal 1106 Platform 1108 Leg 1110 Sound board area 1112 Central sound board area 1114,1120 Perimeter 1116 Axis 1118 Ring 1124 Transducer

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Charles W. Mooney, Kayser Court 7521, Apartment Bee, Lake Worth, Florida, USA (72) Inventor Eving Harold Holden, Boca Raton, Florida, USA San Esta Way, 21363 (72) Inventor Gerald Eugene Brinkley, Wellington Trace, West Palm Beach, Florida, USA 14335 (72) Inventor Philip Paul McNack, West Palm, Florida, USA Beach, horse show trace 447 (JP, U) US Patent 5,327,120 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04R 13/02 H02K 33/02 H04M 1/02 H04Q 7/14

Claims (27)

(57) [Claims] 1. A pedestal comprising: a soundboard having a predetermined resonance frequency for coupling kinetic energy to a user of the device; and a pedestal comprising a platform and a leg coupled to the soundboard on the opposite side. Toko but substantially dimension than smaller <br/> the platform
Filtration of the pedestal; and among the platform and the leg portion
Coupled to the platform along an axis through the heart ,
A transducer for converting an electrical input signal into kinetic energy generated in a direction parallel to the axis, the kinetic energy being transmitted to the sound board through the legs without substantially changing a resonance frequency of the sound board. mass exciting acoustic device, characterized in that it comprises a; transducer being. 2. The mass-excited acoustic device according to claim 1, further comprising a housing coupled to the sound board and housing the pedestal and the transducer. 3. The mass excited acoustic device of claim 1, wherein said platform mechanically supports and secures said transducer to said pedestal. 4. The mass excited acoustic device according to claim 1, wherein said sound board is formed continuously with said pedestal around said leg. 5. The mass excited acoustic device according to claim 1, wherein said sound board has an inner surface connected to said legs and an outer surface having a depression. Wherein said sound board have a shape of elliptical
And radially from the central part having the predetermined thickness to the end part.
Mass exciting sound apparatus thinner claim 1, wherein the predetermined method I. Wherein said soundboard has a circular shape,
The mass-excited acoustic device according to claim 1, wherein the thickness decreases radially from a central portion having a predetermined thickness toward an end portion in a predetermined manner. 8. sound board having a predetermined resonant frequency which bind to the user of the kinetic energy device; a pedestal having a platform, and a leg portion coupled to the sound board at its opposite side, said legs Toko substantially dimension than smaller <br/> the platform
A mass-excited acoustic device comprising : a pedestal; a dual-mode transducer;
The transducer is : along an axis passing through the platform and the center of the leg
Coupled to said platform, the electromagnetic driver generates an alternating electromagnetic field in response to the speech input signal Te; includes and upper <br/> and lower parts of the substantially parallel planes suspension members, coupled to said electromagnetic driver that the armature; become more, the armature is: central rules planar plane peripheral portion definitive around the region-arranged plurality of independent planar circular non-linear spring members; and the planar suspension member and the lower plane of the upper A magnetic kinematic mass suspended between the suspension member and the periphery of the central planar area, wherein the magnetic kinematic mass is alternately moved in response to the alternating electromagnetic field; There through said planar non-linear spring members and said electromagnetic driver, a magnetic moving mass unit to be converted into kinetic energy that will be generated in a direction parallel to said axis; constituted by the kinetic energy Transmitted to the soundboard through without the leg portion substantially altering the resonant frequency of the serial soundboard, mass exciting acoustic device, characterized by providing an audio output having predetermined bass response. Wherein said flat circular non-linear spring members are mass excited acoustic device according to claim 8, further comprising an inner periphery of the circular peripheral edge and an oval. 10. The planar non-linear spring member has a minimum opposing width and a maximum opposing width defined by a difference between the inner peripheral edge and the outer peripheral edge, and the planar non-linear spring member has the maximum opposing width via the maximum opposing width. The mass-excited acoustic device according to claim 9, wherein the mass-excited acoustic device is coupled to a central plane region and the plane peripheral region. 11. The mass-excited acoustic device according to claim 10, wherein the maximum facing width is twice the minimum facing width. 12. The mass excited acoustic device of claim 1, wherein said planar periphery of said electromagnetic driver and said armature has a substantially circular periphery, said electromagnetic driver being coupled to said platform at said periphery. . 13. The apparatus according to claim 1, wherein said planar non-linear spring member has a restoring force.
9. The mass excitation acoustic device according to claim 8 , wherein the magnetic motion mass section moves . 14. The mass excited acoustic device of claim 9 , wherein the kinetic energy generated by the alternating electromagnetic field is acoustic energy responsive to an audible input signal coupled to the electromagnetic driver. 15. The mass excited acoustic device according to claim 14 , wherein the kinetic energy generated by the alternating electromagnetic field is haptic energy responsive to an audible input signal coupled to the electromagnetic driver. 16. The mass-excited acoustic device according to claim 8, wherein the armature and the magnetic kinematic mass constituting the resonance armature system have a fundamental mode resonance frequency and a displacement amplitude. 17. The mass excited acoustic device according to claim 16, wherein the displacement amplitude of the magnetic kinematic mass increases nonlinearly in a predetermined frequency range exceeding a resonance frequency of a fundamental mode. 18. A sound transmission system comprising : a sound source for generating a sound input signal; processing means for processing the sound input signal to drive a transducer; and one or more mass excitation sound devices;
A pedestal comprising: a soundboard having a predetermined resonance frequency for coupling kinetic energy to a user of the device; a platform and legs opposite the soundboard coupled to the soundboard , wherein the legs are < br /> substantially Toko dimension is smaller than the platform
Filtration of the pedestal; along an axis passing through the center of the platform and the leg portion
Coupled to said platform Te, a transducer for converting an audio input signal to the kinetic energy that is generated in a direction parallel to said axis, said through said leg without substantially changing the resonance frequency of the soundboard A sound transmission system, comprising: a transducer for transmitting kinetic energy to a sound board; and a housing coupled to the sound board and surrounding the pedestal and the transducer. 19. At least one mass excited acoustic device is provided.
19. The audio transmission system according to claim 18, further comprising a headband supporting the mass excited acoustic device around the user's head . 20. The transducer according to claim 19, wherein: the transducer is: along an axis passing through the center of the platform and the leg.
Comprises and upper and lower substantially parallel planar suspension members, the armature is coupled to said electromagnetic driver; coupled to said platform Te, the electromagnetic driver generates an alternating electromagnetic field in response to an input signal become more the armature is: a plurality of independent planar circular non-linear spring members arranged regularly in a plane peripheral portion around the central planar area; the between and the planar suspension member and a lower planar suspension member of the upper A magnetic kinematic mass suspended around a central plane region, wherein the magnetic kinematic mass is alternately moved in response to the alternating electromagnetic field, wherein the motion of the magnetic kinematic mass is in parallel with the planar non-linear spring member. said through an electromagnetic driver, a magnetic moving mass unit to be converted into kinetic energy that will be generated in a direction parallel to said axis; sound transmitting according to claim 18, wherein constituted by Shi Stem. 21. The voice transmission system of claim 19 wherein said flat circular non-linear spring member has an inner peripheral edge of the circular peripheral edge and an oval. 22. A housing having a portion forming a sound board having a predetermined resonance frequency; a receiver housed in the housing for receiving and detecting a transmitted encoded message signal; processing means for processing the message signal; and transducer; a more composed personal communication device, the transducin
Sa is along an axis passing through the center of the platform and the leg portion
Includes an upper and lower substantially parallel planar suspension members; coupled to said platform, the electromagnetic driver generates an alternating electromagnetic field in response to the processed encoded message signal is coupled thereto Te
Coupled to said electromagnetic driver, you around the central planar region
An armature constituted by a plurality of independent planar circular non-linear spring members regularly arranged within a planar periphery of the armature;
And a magnetic moving mass unit to be suspended around the central planar region between the planar suspension member and a lower planar suspension member of the upper, alternating the magnetic moving mass portion in response to said alternating electromagnetic field is moved to the through movement of the magnetic moving mass portion and the planar non-linear spring members and said electromagnetic driver, a magnetic moving mass unit to be converted into kinetic energy that will be generated in a direction parallel to said axis; be constituted by A personal communication device characterized by the above-mentioned. 23. The personal communications device of claim 22, wherein said flat circular non-linear spring member has an inner peripheral edge of the circular peripheral edge and an oval. 24. The encoded message signal includes at least one address signal associated therewith, and wherein said processing means responds to said electromagnetic driver in response to detecting an address signal matching a predetermined personal communication device address. Generates a combined audible alert signal and responds to the alternating electromagnetic field
Is constituted by a controller for generating the movement of the magnetic moving mass unit, wherein a planar nonlinear spring member is converted into tactile energy through an electromagnetic driver, claim 22 provides a vibrational response that is coupled to the user through the soundboard A personal communication device as described. 25. The encoded message signal includes a voice message signal associated with a received address, and wherein the processing means processes the detected voice message signal coupled to the electromagnetic driver and responds thereto. issued an alternating magnetic field
Is live, the movement of the magnetic moving mass unit, wherein a planar nonlinear spring member is converted into acoustic energy through an electromagnetic driver, personal of claim 24 which provides an audible response which is coupled to the user through the soundboard Communication device. 26. The method of claim 25, wherein the processing means is a personal communication device of claim 24, further comprising a high pass filter to make attenuating a received voice message signals below 150 Hz. 27. The encoded message signal further includes a call waiting signal included in a voice message signal, wherein the processing means processes the call waiting signal and the voice message signal, and wherein the movement of the magnetic kinematic mass is in the plane. 25. The personal communication device of claim 24, wherein the personal communication device is converted to haptic and acoustic energy through a non-linear spring member and the electromagnetic driver to provide both a vibrational and audible response coupled to a user through the sound board.