JPH0570992B2 - - Google Patents
Info
- Publication number
- JPH0570992B2 JPH0570992B2 JP20661081A JP20661081A JPH0570992B2 JP H0570992 B2 JPH0570992 B2 JP H0570992B2 JP 20661081 A JP20661081 A JP 20661081A JP 20661081 A JP20661081 A JP 20661081A JP H0570992 B2 JPH0570992 B2 JP H0570992B2
- Authority
- JP
- Japan
- Prior art keywords
- cabinet
- diaphragm
- pressure
- sealed
- sealed cabinet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000006073 displacement reaction Methods 0.000 claims description 27
- 238000001514 detection method Methods 0.000 claims description 15
- 239000007788 liquid Substances 0.000 claims description 9
- 230000004044 response Effects 0.000 description 4
- 238000009835 boiling Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- AJDIZQLSFPQPEY-UHFFFAOYSA-N 1,1,2-Trichlorotrifluoroethane Chemical group FC(F)(Cl)C(F)(Cl)Cl AJDIZQLSFPQPEY-UHFFFAOYSA-N 0.000 description 2
- 229920001328 Polyvinylidene chloride Polymers 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000005033 polyvinylidene chloride Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- CYRMSUTZVYGINF-UHFFFAOYSA-N trichlorofluoromethane Chemical compound FC(Cl)(Cl)Cl CYRMSUTZVYGINF-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/002—Damping circuit arrangements for transducers, e.g. motional feedback circuits
Description
本発明は、密閉したキヤビネツトの内部に１成
分又は複数成分よりなる気体と液体の２相を共存
するスピーカ装置の内部圧力の制御装置に関する
ものである。
最近のオーデイオ機器においては、高忠実度の
再生が可能なスピーカ装置が要望されており、音
圧周波数特性のすぐれた平板振動板を備えた密閉
型スピーカ装置が着目されている。
密閉型スピーカ装置において、その低減限界を
定める最低共振周波数f0は次式で表わされる。
The present invention relates to an internal pressure control device for a speaker device in which two phases, gas and liquid, each consisting of one or more components, coexist inside a sealed cabinet. In recent audio equipment, there is a demand for speaker devices capable of high-fidelity reproduction, and closed-type speaker devices equipped with flat diaphragms with excellent sound pressure frequency characteristics are attracting attention. In a closed-type speaker device, the lowest resonant frequency f 0 that determines the reduction limit is expressed by the following equation.
【化】
ただし、S1はスピーカのステイフネス、S2はキ
ヤビネツトのステイフネス、Ｍは付加質量を含め
たスピーカ振動系の質量である。
さらにS2は
S2＝γPA2／Ｖ ……(2)
で表わされる。ただし、γは比熱比（空気の場合
1.4）、Ｐはキヤビネツト内の圧力（通常 １気圧
＝105N／m2）、Ａはスピーカの開口面積、Ｖはキ
ヤビネツトの体積である。したがつて、Ｖの小さ
な小型スピーカ装置においてはS2が大となり、そ
の結果、式(1)におけるf0が高くなるため、低音再
生を十分に行なうことができない。
ところで、キヤビネツトの内部を１成分又は複
数成分よりなる気体と液体の２相を共存する状態
に保持すると見掛け上のγが小さくなり、その結
果、S2の小さなキヤビネツトにすることができ、
低音再生に効果がある。この方法を実施する場合
は、キヤビネツトの内部圧力が外部圧力と等しく
なるようキヤビネツト内部の温度を調整保持する
必要がある。キヤビネツトの内部圧力と外部圧力
との間に圧力差があると振動板の位置を正しい位
置に保持することができないからである。
第１図は従来の密閉型のスピーカ装置を示して
いる。同図において、１はキヤビネツト、２はス
ピーカの振動板、３は液体、４は温度センサ、５
はヒータ、６は制御回路であつて、キヤビネツト
１内の温度を温度センサ４が検知して、その出力
により制御回路６がヒータ５を制御する。
ところで、この方式はキヤビネツト内部の温度
分布がキヤビネツトの形状、大きさ等によつて異
なるため、温度センサの取付位置に問題のあるこ
と、温度の変化と圧力の変化に時間的なずれがあ
るため、応答速度が遅いことなどの欠点がある。
本発明は、上記のような欠点のない温度（圧
力）制御装置を備えた密封型スピーカ装置を提供
することを目的とするものである。
本発明は、振動板を取付けた密閉キヤビネツト
の内部に１成分又は複数成分からなる気体と液体
の２相を共存するスピーカ装置において、前記密
閉キヤビネツトの内部圧力を検出する圧力センサ
あるいは前記振動板の変位を検出する変位検出セ
ンサと、前記圧力センサあるいは変位検出センサ
の出力によつて動作する温度制御装置とを備え、
前記密閉キヤビネツトの内部圧力を外部圧力と等
しくするよう調整、保持することを特徴とする密
封型スピーカ装置である。
以下、本発明の実施例を第２図について説明す
る。１は密閉キヤビネツト、２はスピーカの振動
板、３は液体、５はヒータ、６は制御回路、７は
圧力センサである。なお、常温において、密閉キ
ヤビネツト１内で気体と前記液体３の２相を共存
する物質としては、例えば、フロン113（CCl3F−
CCl2F、沸点47.6℃）や、フロン11（CCl3F、沸点
23.8℃）などが使用できるが、キヤビネツトを冷
却するのは困難なので沸点が常温よりもやや高い
フロン113を使用する。
第１図の従来の装置では、温度センサ４により
キヤビネツト内部の温度を検出し、その出力によ
つて制御回路６がヒータ５を制御しているのを、
本実施例は、圧力センサ７によつてキヤビネツト
１内の圧力を検出し、その出力によつてヒータ５
と制御回路６とよりなる温度制御装置を作動さ
せ、密閉キヤビネツト１の内部温度を制御するも
のである。
密閉キヤビネツト１の内部温度を調節するのは
キヤビネツト内外の圧力を等しくするためであ
る。従来の装置は温度センサによつてキヤビネツ
トの内部温度を検出していたため、前述のような
障害があつたが、本実施例においては、圧力セン
サ７によりキヤビネツト１の内部圧力を直接検出
するから前述のような障害はない。すなわち、キ
ヤビネツト内部の圧力の変化は、キヤビネツト内
部に均一に波及するので、圧力センサ７の取付位
置に制限はなく、かつ圧力の変化を圧力センサ７
が直接感知するから応答が早い。
この圧力センサ７にはシリコンダイアフラム型
や差動キヤパシタンス型の圧力センサが採用され
る。
第３図は特許請求の範囲２の発明の実施例を示
している。この実施例は、密閉キヤビネツト１の
内部圧力又は外部圧力の変化による振動板２の変
位を変位検出センサ８によつて検出し、その出力
によつて温度制御装置（ヒータ５および制御回路
６）を動作させるものである。キヤビネツト内外
の圧力を等しくするのは、振動板２の変位を防止
することにある。したがつて、振動板２の変位を
直接検出することは、本発明の終局の目的により
近づくことになる。
変位検出センサ８は、振動板２に近接して設け
られ、キヤビネツト内外の圧力の相違に基づく振
動板２の変位を検出する。振動板２は、スピーカ
の入力によつて振動するが、変位検出センサ８が
振動板２の変位のみを検出するように設定するこ
とは容易である。
第３図の実施例においては、変位検出センサ８
は中高音用振動板２′に近接して設けてある。こ
の理由としては、中高音用振動板２′は、低音用
振動板２よりも口径が小さく、その振動範囲が、
低音用振動板２では１mm〜１cm以上であるのに対
し、中高音用振動板２′では微小であるため、変
位検出センサ８を振動板に近接して設けることが
できるからである。
第４図は、特許請求の範囲２に記載された発明
の他の実施例である。この実施例は変位検出セン
サ８を密閉キヤビネツト１の外部に設けたもので
あつて、キヤビネツト内部の雰囲気に影響される
ことなく振動板２の変位を検出することができ
る。
なお、振動板２、エツジの材料については、振
動板２にはアルミハニカムを、またエツジにはガ
スの透過率が極めて小さいポリ塩化ビニリデンと
エラストマとをラミネートしたもの用いればよ
い。また変位検出センサ８には静電容量型や渦電
流型が用いられる。これらの変位検出センサ８は
1μｍ程度の変位を容易に検出することができる。
一方、振動板２のステイフネスはせいぜい
5000N／ｍ程度なので、1μｍの変位は0.005Nの
力で得られることになり、振動板２の面積を10cm2
とすれば1/20000気圧の変化を検出できることに
なる。
以上のように上記の実施例によれば、例えば、
口径12cmで、Ｍ＝0.01Kg、S1＝1000N／ｍのスピ
ーカユニツト単体のf0は前記式(1)より50Hzとな
り、このユニツトを容積が0.002m3の密閉キヤビ
ネツト１に取り付けたとするとキヤビネツトのス
テイフネスS2はS2＝9000N／ｍとなり、スピーカ
システムのf0は約160Hzとなるが、キヤビネツト
内を２相共存状態に保つと、密閉キヤビネツト１
の体積変化は２相の間の相変態によつて吸収され
圧力変化を起こさない。すなわち見かけ上、比熱
比が０となり、その結果S2＝０となる。実験では
S2の値は通常の約1/8に低下し、その結果f0は73
Hzとなり、従来に比べて低域再生限界が大きく広
がるものである。
以上述べたように、本発明の密閉型スピーカ装
置は、密閉キヤビネツトの内部圧力又は振動板の
変位を直接検出して、密閉キヤビネツトの内部圧
力を調整するものであつて、従来の温度検出方式
のもつセンサの取付位置の問題や応答速度が遅い
という欠点を解消する調整方式であることは前述
のとおりであるから、冒頭で述べた本発明の所期
の目的を達成する効果を有する。[C] Here, S 1 is the stiffness of the speaker, S 2 is the stiffness of the cabinet, and M is the mass of the speaker vibration system including the additional mass. Further, S 2 is expressed as S 2 =γPA 2 /V (2). However, γ is the specific heat ratio (in the case of air
1.4), P is the pressure inside the cabinet (usually 1 atm = 10 5 N/m 2 ), A is the opening area of the speaker, and V is the volume of the cabinet. Therefore, in a small speaker device with a small V, S 2 becomes large, and as a result, f 0 in equation (1) becomes high, making it impossible to sufficiently reproduce bass sounds. By the way, if the interior of the cabinet is maintained in a state where two phases of gas and liquid consisting of one or more components coexist, the apparent γ becomes smaller, and as a result, the cabinet can be made with a smaller S2 .
Effective for bass reproduction. When carrying out this method, it is necessary to adjust and maintain the temperature inside the cabinet so that the internal pressure of the cabinet is equal to the external pressure. This is because if there is a pressure difference between the internal pressure and the external pressure of the cabinet, the position of the diaphragm cannot be maintained in the correct position. FIG. 1 shows a conventional closed-type speaker device. In the figure, 1 is a cabinet, 2 is a speaker diaphragm, 3 is a liquid, 4 is a temperature sensor, and 5 is a
1 is a heater, and 6 is a control circuit in which a temperature sensor 4 detects the temperature inside the cabinet 1, and the control circuit 6 controls the heater 5 based on its output. By the way, with this method, the temperature distribution inside the cabinet varies depending on the shape and size of the cabinet, so there are problems with the mounting position of the temperature sensor, and there is a time lag between temperature changes and pressure changes. , has drawbacks such as slow response speed. SUMMARY OF THE INVENTION An object of the present invention is to provide a sealed speaker device equipped with a temperature (pressure) control device that does not have the above drawbacks. The present invention provides a speaker device in which two phases of gas and liquid consisting of one or more components coexist inside a sealed cabinet to which a diaphragm is attached, and a pressure sensor for detecting the internal pressure of the sealed cabinet or a pressure sensor for detecting the internal pressure of the diaphragm. comprising a displacement detection sensor that detects displacement, and a temperature control device that operates based on the output of the pressure sensor or the displacement detection sensor,
The sealed speaker device is characterized in that the internal pressure of the sealed cabinet is adjusted and maintained to be equal to the external pressure. Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1 is a sealed cabinet, 2 is a speaker diaphragm, 3 is a liquid, 5 is a heater, 6 is a control circuit, and 7 is a pressure sensor. An example of a substance that coexists in two phases, gas and liquid 3, in the sealed cabinet 1 at room temperature is Freon 113 (CCl 3 F-
CCl 2 F, boiling point 47.6℃) and Freon 11 (CCl 3 F, boiling point
(23.8℃) can be used, but since it is difficult to cool the cabinet, Freon 113, whose boiling point is slightly higher than room temperature, is used. In the conventional device shown in FIG. 1, a temperature sensor 4 detects the temperature inside the cabinet, and a control circuit 6 controls a heater 5 based on its output.
In this embodiment, the pressure inside the cabinet 1 is detected by the pressure sensor 7, and the heater 5 is
The internal temperature of the sealed cabinet 1 is controlled by operating a temperature control device comprising a control circuit 6 and a control circuit 6. The purpose of regulating the internal temperature of the sealed cabinet 1 is to equalize the pressure inside and outside the cabinet. The conventional device used a temperature sensor to detect the internal temperature of the cabinet, which caused the above-mentioned problems, but in this embodiment, the pressure sensor 7 directly detects the internal pressure of the cabinet 1. There are no such obstacles. That is, since changes in the pressure inside the cabinet spread uniformly inside the cabinet, there are no restrictions on the mounting position of the pressure sensor 7, and changes in pressure can be detected by the pressure sensor 7.
The response is quick because it is directly sensed. As the pressure sensor 7, a silicon diaphragm type pressure sensor or a differential capacitance type pressure sensor is adopted. FIG. 3 shows an embodiment of the invention claimed in claim 2. In this embodiment, a displacement detection sensor 8 detects the displacement of the diaphragm 2 due to a change in the internal pressure or external pressure of the sealed cabinet 1, and the temperature control device (heater 5 and control circuit 6) is controlled by the output of the displacement detection sensor 8. It is something that makes it work. The purpose of equalizing the pressure inside and outside the cabinet is to prevent displacement of the diaphragm 2. Therefore, directly detecting the displacement of the diaphragm 2 comes closer to the ultimate objective of the present invention. Displacement detection sensor 8 is provided close to diaphragm 2 and detects displacement of diaphragm 2 based on the difference in pressure inside and outside the cabinet. Although the diaphragm 2 vibrates in response to input from the speaker, it is easy to set the displacement detection sensor 8 to detect only the displacement of the diaphragm 2. In the embodiment of FIG. 3, the displacement detection sensor 8
is provided close to the middle and high frequency diaphragm 2'. The reason for this is that the diaphragm 2' for medium and high frequencies has a smaller diameter than the diaphragm 2 for low frequencies, and its vibration range is
This is because the displacement detection sensor 8 can be provided close to the diaphragm because the diaphragm 2' for medium and high frequencies is minute, whereas the diaphragm 2 for bass sounds has a diameter of 1 mm to 1 cm or more. FIG. 4 shows another embodiment of the invention set forth in claim 2. In this embodiment, the displacement detection sensor 8 is provided outside the sealed cabinet 1, and the displacement of the diaphragm 2 can be detected without being affected by the atmosphere inside the cabinet. Regarding the materials of the diaphragm 2 and the edges, aluminum honeycomb may be used for the diaphragm 2, and a laminate of polyvinylidene chloride and elastomer, which have extremely low gas permeability, may be used for the edges. Further, the displacement detection sensor 8 is of a capacitance type or an eddy current type. These displacement detection sensors 8
Displacements of about 1 μm can be easily detected.
On the other hand, the stiffness of diaphragm 2 is at most
Since it is about 5000N/m, a displacement of 1μm can be obtained with a force of 0.005N, and the area of the diaphragm 2 is 10cm 2
If so, changes of 1/20000 atmospheric pressure can be detected. As described above, according to the above embodiment, for example,
The f 0 of a single speaker unit with a diameter of 12 cm, M = 0.01 Kg, and S 1 = 1000 N/m is 50 Hz from the above equation (1). If this unit is installed in a sealed cabinet 1 with a volume of 0.002 m 3 , the cabinet's f 0 is 50 Hz. The stiffness S 2 is S 2 = 9000 N/m, and the f 0 of the speaker system is approximately 160 Hz. However, if the two-phase coexistence condition is maintained within the cabinet, the sealed cabinet 1
The volume change is absorbed by the phase transformation between the two phases and does not cause a pressure change. That is, the specific heat ratio apparently becomes 0, and as a result, S 2 =0. In the experiment
The value of S 2 drops to about 1/8 of the normal value, resulting in f 0 of 73
Hz, which significantly expands the low-frequency reproduction limit compared to conventional models. As described above, the sealed speaker device of the present invention adjusts the internal pressure of the sealed cabinet by directly detecting the internal pressure of the sealed cabinet or the displacement of the diaphragm, and is capable of adjusting the internal pressure of the sealed cabinet by directly detecting the internal pressure of the sealed cabinet or the displacement of the diaphragm. As described above, this adjustment method solves the problem of the mounting position of the sensor and the slow response speed, so it has the effect of achieving the intended purpose of the present invention as stated at the beginning.
第１図：従来の密閉型スピーカ装置を示す図、
第２図：特許請求の範囲１に記載された発明の実
施例を示す図、第３図：特許請求の範囲２に記載
された発明の実施例を示す図、第４図：特許請求
の範囲２に記載された発明の他の実施例を示す図
〔記号〕、１…密閉キヤビネツト、２，２′……
振動板、３……液体、４……温度センサ、５……
ヒータ、６……制御回路、７……圧力センサ、８
……変位検出センサ。
Figure 1: Diagram showing a conventional closed-type speaker device,
Figure 2: A diagram showing an example of the invention described in claim 1, Figure 3: A diagram showing an example of the invention described in claim 2, Figure 4: Claims Figures showing other embodiments of the invention described in 2 [Symbols], 1... Sealed cabinet, 2, 2'...
Vibration plate, 3...Liquid, 4...Temperature sensor, 5...
Heater, 6... Control circuit, 7... Pressure sensor, 8
...Displacement detection sensor.
Claims (1)
１成分又は複数成分よりなる気体と液体の２相を
共存するスピーカ装置において、前記密閉キヤビ
ネツトの内部圧力を検出する圧力センサと、該圧
力センサの出力によつて動作する温度制御装置と
を備え、前記密閉キヤビネツトの内部圧力を外部
圧力と等しくするよう調整保持することを特徴と
する密閉型スピーカ装置。 ２ 振動板を取付けた密閉キヤビネツトの内部に
１成分又は複数成分よりなる気体と液体の２相を
共存するスピーカ装置において、前記振動板の変
位を検出する変位検出センサと、該変位検出セン
サの出力によつて動作する温度制御装置とを備
え、前記密閉キヤビネツトの内部圧力を外部圧力
と等しくするよう調整保持することを特徴とする
密閉型スピーカ装置。 ３ 特許請求の範囲２において、前記変位検出セ
ンサを、前記密閉キヤビネツトの外部に、前記振
動板に近接して設けたことを特徴とする密閉型ス
ピーカ装置。[Scope of Claims] 1. A speaker device in which two phases of gas and liquid made of one or more components coexist inside a sealed cabinet to which a diaphragm is attached, including a pressure sensor for detecting the internal pressure of the sealed cabinet; What is claimed is: 1. A closed-type speaker device comprising: a temperature control device operated by the output of the pressure sensor, and adjusting and maintaining the internal pressure of the sealed cabinet to be equal to the external pressure. 2. In a speaker device in which two phases of gas and liquid consisting of one or more components coexist inside a sealed cabinet to which a diaphragm is attached, a displacement detection sensor that detects displacement of the diaphragm and an output of the displacement detection sensor are provided. 1. A closed-type speaker device, comprising: a temperature control device operated by a temperature control device, which adjusts and maintains the internal pressure of the sealed cabinet to be equal to the external pressure. 3. The sealed speaker device according to claim 2, wherein the displacement detection sensor is provided outside the sealed cabinet and close to the diaphragm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20661081A JPS58106989A (en) | 1981-12-21 | 1981-12-21 | Closed speaker device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20661081A JPS58106989A (en) | 1981-12-21 | 1981-12-21 | Closed speaker device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58106989A JPS58106989A (en) | 1983-06-25 |
| JPH0570992B2 true JPH0570992B2 (en) | 1993-10-06 |
Family
ID=16526229
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20661081A Granted JPS58106989A (en) | 1981-12-21 | 1981-12-21 | Closed speaker device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58106989A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ITMI20041972A1 (en) * | 2004-10-18 | 2005-01-18 | Daniele Ramenzoni | ELECTRO-ACOUSTIC DEVICE, WITH CAVITY RESONATOR, THAT PROVIDES EXTREME THREE-DIMENSIONAL CHARACTERISTICS TO CONTROL, CONCENTRATE AND SPREAD INFRASOUNDS, SOUNDS AND ULTRASOUNDS. |
| DE102012222447B3 (en) | 2012-12-06 | 2014-05-28 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | SPEAKER WITH PRESSURE COMPENSATION ELEMENT |
| JP2016225690A (en) * | 2015-05-27 | 2016-12-28 | 京セラ株式会社 | Electronic device and control method of the same |
-
1981
- 1981-12-21 JP JP20661081A patent/JPS58106989A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58106989A (en) | 1983-06-25 |
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