JPH0691974B2 - Cyclone type dust collector - Google Patents

Cyclone type dust collector

Info

Publication number
JPH0691974B2
JPH0691974B2 JP35190291A JP35190291A JPH0691974B2 JP H0691974 B2 JPH0691974 B2 JP H0691974B2 JP 35190291 A JP35190291 A JP 35190291A JP 35190291 A JP35190291 A JP 35190291A JP H0691974 B2 JPH0691974 B2 JP H0691974B2
Authority
JP
Japan
Prior art keywords
chamber
outer cylinder
cylinder
type dust
dust
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
Application number
JP35190291A
Other languages
Japanese (ja)
Other versions
JPH05161861A (en
Inventor
寿 今井
Original Assignee
寿 今井
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 寿 今井 filed Critical 寿 今井
Priority to JP35190291A priority Critical patent/JPH0691974B2/en
Publication of JPH05161861A publication Critical patent/JPH05161861A/en
Publication of JPH0691974B2 publication Critical patent/JPH0691974B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は集塵に用いる分級精度に
優れたサイクロン型集塵装置に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cyclone type dust collecting apparatus which is used for dust collection and has excellent classification accuracy.

【0002】[0002]

【従来の技術】従来より図3に示すようなサイクロン型
の集塵装置が使用されている。即ち、コーン部50の上
端に連続した円筒部51に突設してなる含塵流体流入管
52から接線方向に個体粒子を含む気体を高速で流入す
ると共に、該流入に伴って内部に生ずる旋回気流によっ
て粒径及び比重の大きい粒子が遠心力の作用によって外
壁に向かって沈降し、器壁に沿ってコーン部50に下降
して該コーン部50下端の排出口から排出される。一
方、大径または比重の大きい粒子を除去された円筒部5
1中央に位置する気体は、該軸芯位置に上壁53から導
入した排気管54の負圧によって吸引されるようになっ
ている。
2. Description of the Related Art Conventionally, a cyclone type dust collector as shown in FIG. 3 has been used. That is, a gas containing solid particles is introduced at a high speed in a tangential direction from a dust-containing fluid inflow pipe 52 protruding from a cylindrical portion 51 that is continuous with the upper end of the cone portion 50, and a swirl that occurs inside due to the inflow is generated. Due to the action of centrifugal force, particles having a large particle size and a large specific gravity are settled toward the outer wall by the air flow, descend to the cone portion 50 along the vessel wall, and are discharged from the discharge port at the lower end of the cone portion 50. On the other hand, the cylindrical portion 5 from which particles having a large diameter or a large specific gravity have been removed
1 The gas located at the center is sucked by the negative pressure of the exhaust pipe 54 introduced from the upper wall 53 to the axial center position.

【0003】そして、一般にこの種の遠心分離による分
級粒子径δ〔cm〕は、式1に示す計算式で決定され
る。ここで円周方向流速vθ〔cm/s〕は、含塵流体
導入管52からの供給輸送速度である。
In general, the classified particle size δ [cm] of this kind of centrifugation is determined by the calculation formula shown in Formula 1. Here, the circumferential flow velocity vθ [cm / s] is the supply / transport velocity from the dust-containing fluid introduction pipe 52.

【0004】[0004]

【式1】 [Formula 1]

【0005】[0005]

【発明が解決しようとする課題】しかし上記式1から判
るように、分級粒子径δ〔cm〕は排気管54からの吸
引速度v〔cm/s〕、即ち出口パイプ径断面での流速
の影響を強く受けるが、従来のこの種の装置では、該排
気管54の断面方向の流速分布が一定しないため、分級
粒子径δ〔cm〕のばらつきが大きくなり、分級精度に
問題を有していた。
However, as can be seen from the above equation 1, the classification particle size δ [cm] is influenced by the suction speed v [cm / s] from the exhaust pipe 54, that is, the flow velocity in the outlet pipe diameter cross section. However, in the conventional apparatus of this type, since the flow velocity distribution in the cross-sectional direction of the exhaust pipe 54 is not constant, the classified particle diameter δ [cm] has a large variation, and there is a problem in the classification accuracy. .

【0006】本発明は上記問題に鑑みてなされたもので
あり、分級精度に優れた分級装置或は分級集塵装置に使
用する新規構成のサイクロン型集塵装置を提供すること
を目的とするものである。
The present invention has been made in view of the above problems, and an object of the present invention is to provide a cyclone-type dust collecting device having a new structure for use in a classifying device or a classification dust collecting device having excellent classification accuracy. Is.

【0007】[0007]

【課題を解決するための手段】本発明に係るサイクロン
型集塵装置は、逆円錐状のコーン部の上端に円筒部を連
設し、下端に粗粒排出口を開口した分級室を構成すると
共に、該分級室に円錐台状の反転盤を架設し、分級室に
含塵流体流入管と微粒排出口を設けてなるサイクロン型
集塵装置において、前記微粒排出口を、円筒部の上壁軸
芯に位置して設けた外筒に対して内筒を同芯状に内挿
し、且つ分級室4に延びる両筒の反転盤からの距離を外
筒が内筒より長く構成した分流排気構造とすると共に、
前記含塵流体流入管を前記外筒の外側に位置して同芯状
に形成した円筒状分流室の一側から含接線方向に突出
し、該円筒状分流室の下端部に位置して分流筒の内壁か
ら内径方向に向かって渦状に傾斜した複数の分流翼を突
設した含塵流体流入口を構成したことを要旨とするもの
である。
A cyclone type dust collecting apparatus according to the present invention constitutes a classifying chamber in which a cylindrical portion is continuously provided at an upper end of an inverted conical cone portion and a coarse particle discharge port is opened at a lower end thereof. In addition, in the cyclone-type dust collector in which a frustoconical inversion plate is installed in the classification chamber, and a dust-containing fluid inflow pipe and a fine particle discharge port are provided in the classification chamber, the fine particle discharge port is provided on the upper wall of the cylindrical portion. A split flow exhaust structure in which an inner cylinder is concentrically inserted into an outer cylinder provided at an axial center, and the distance between the two cylinders extending to the classification chamber 4 from the reversal plate is longer than the inner cylinder. And
The dust-containing fluid inflow pipe is located outside the outer cylinder and protrudes in a tangential direction from one side of a cylindrical diversion chamber formed concentrically, and is located at the lower end of the cylindrical diversion chamber. The gist of the present invention is that the dust-containing fluid inlet is formed by projecting a plurality of flow-dividing vanes that are spirally inclined from the inner wall to the inner diameter direction.

【0008】また前記分流排気構造は、直径dの外筒に
対して直径略0.7dの内筒を同芯状に内挿すると共
に、分級室に延びる両筒の反転盤からの距離が、外筒の
Lに対して内筒は略1/2Lになるように構成すること
が好ましい。
In the split exhaust structure, an inner cylinder having a diameter of about 0.7d is concentrically inserted into an outer cylinder having a diameter d, and the distances of both cylinders extending into the classification chamber from the reversing plate are: It is preferable to configure the inner cylinder to be approximately 1/2 L with respect to the outer cylinder L.

【0009】[0009]

【作用】上記構成では、分級室の軸芯位置に上壁から内
挿した微粒排出側構造が外筒と内筒の断面積を二分割し
た分流排気構造になり、パイプの断面方向で均一な流速
を確保することができる。従って前式1の吸引速度v
〔cm/s〕が一定となり、分級粒子径δ〔cm〕を一
定にすることができる。
In the above construction, the fine particle discharge side structure inserted from the upper wall at the axial center position of the classification chamber is a split flow exhaust structure in which the cross-sectional areas of the outer cylinder and the inner cylinder are divided into two parts, which are uniform in the cross-sectional direction of the pipe. The flow velocity can be secured. Therefore, the suction speed v of the previous equation 1
[Cm / s] becomes constant, and the classified particle diameter δ [cm] can be made constant.

【0010】[0010]

【実施例】以下、本発明に係るサイクロン型集塵装置の
一実施例を図1及び図2に従って説明する。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cyclone type dust collecting apparatus according to the present invention will be described below with reference to FIGS.

【0011】符号1は逆円錐状のコーン部2の上端に連
続した円筒部であり、コーン部2の下端に粗粒排出口3
を開口すると共に、分級室4には円筒部1の下端軸芯C
Lに位置して頂端に円盤面6を有する円錐台状の反転盤
5を架設してなる。
Reference numeral 1 denotes a cylindrical portion which is continuous with the upper end of an inverted cone-shaped cone portion 2, and has a coarse grain discharge port 3 at the lower end of the cone portion 2.
And the lower end axis C of the cylindrical portion 1 is opened in the classification chamber 4.
A truncated cone-shaped reversing plate 5 having a disk surface 6 at the top is located at L.

【0012】また上記円筒部1の上壁7には、軸芯CL
に位置して分流排気構造8と渦流流入構造9が構成され
る。該分流排気構造8は、直径dの外筒10に直径0.
7dの内筒11を同芯状に内挿したものであり、分級室
4に延びる両筒10,11の反転盤5の円盤面6からの
距離は、外筒10がLであるのに対して内筒11は1/
2Lになるように構成してある。そして該両筒10,1
1は、微粒排出口12として吸引装置(図示せず)に連
通する。
The upper wall 7 of the cylindrical portion 1 has an axial center CL
A split flow exhaust structure 8 and a vortex flow inflow structure 9 are formed at the position. The split exhaust structure 8 has an outer cylinder 10 having a diameter of d.
The inner cylinder 11 of 7d is inserted concentrically, and the distance of both cylinders 10 and 11 extending into the classification chamber 4 from the disk surface 6 of the reversing disk 5 is L in comparison with the outer cylinder 10. The inner cylinder 11 is 1 /
It is configured to be 2L. And the both cylinders 10, 1
1 communicates with a suction device (not shown) as a fine particle discharge port 12.

【0013】上記渦流流入構造9は、分流筒13によっ
て上記外筒10の外側に位置して同芯状に形成した円筒
状分流室14の一側から含塵流体流入管15を接線方向
に突出すると共に、該円筒状分流室14の下端部に位置
して分流筒13の内壁から内径方向に向かって渦状に傾
斜(渦流方向A)した複数(実施例では6個)の分流翼
16,16…を突設した含塵流体流入口17を構成して
なる。そして含塵流体流入管15から、被分級粒子を含
んだ気体を所定の輸送速度(12〜20m/s)で供給
する。
The vortex inflow structure 9 has a dust-containing fluid inflow pipe 15 projecting tangentially from one side of a cylindrical flow dividing chamber 14 which is located outside the outer cylinder 10 by a flow dividing cylinder 13 and is concentrically formed. In addition, a plurality (six in the embodiment) of the flow dividing blades 16 and 16 located at the lower end of the cylindrical flow dividing chamber 14 and being inclined (vortex flow direction A) from the inner wall of the flow dividing cylinder 13 toward the inner diameter direction. The dust-containing fluid inlet 17 is provided so as to project. Then, the gas containing the particles to be classified is supplied from the dust-containing fluid inflow pipe 15 at a predetermined transport speed (12 to 20 m / s).

【0014】上記構成になるサイクロン型集塵装置は、
被分級粒子を含んだ気体を含塵流体導入管15から供給
することによって、粗粒を粗粒排出口3から、また微粒
を含んだ気体を微粒排出口12から分離回収するもので
あり、この分離点を変更することによって微粒排出口1
2から気体のみを回収する集塵装置とすることができ
る。
The cyclone type dust collector having the above structure is
By supplying the gas containing the particles to be classified from the dust-containing fluid introducing pipe 15, the coarse particles are separated and recovered from the coarse particle outlet 3, and the gas containing the fine particles is separated and recovered from the fine particle outlet 12. Fine particle outlet 1 by changing the separation point
It is possible to use a dust collector that collects only the gas from 2.

【0015】上記構成によれば、含塵流体導入管15か
ら円筒状分流室14に流入した含塵流体は渦流流入構造
9の分流翼16,16…によって矢印A方向の渦流とな
って分級室4に向かって噴出し、次第に沈降(沈降方向
F1)するようになる。然るに、該分級室4では分流排
気構造8によって外筒10と内筒11の筒状排気流路及
び内筒11の管通路が形成され、而も断面積が二分割さ
れているため、両流路から吸引される均一な平行気体流
速(流速方向F2)によって中心CLに向かう均等な求
心力が作用するようになり、気体中に含有する粒子は渦
流によって生じる遠心力F3と該求心力F2の差と、前
記沈降力F1の合力方向Fに落下する。
According to the above construction, the dust-containing fluid flowing from the dust-containing fluid introducing pipe 15 into the cylindrical flow dividing chamber 14 becomes a vortex in the direction of arrow A by the flow dividing blades 16, 16 ... It spouts toward No. 4 and gradually sinks (settling direction F1). However, in the classification chamber 4, the split exhaust structure 8 forms the tubular exhaust passages of the outer cylinder 10 and the inner cylinder 11 and the pipe passage of the inner cylinder 11, and since the cross-sectional area is divided into two, both flows are separated. Due to the uniform parallel gas flow velocity (flow velocity direction F2) sucked from the passage, a uniform centripetal force toward the center CL acts, and the particles contained in the gas have a centrifugal force F3 generated by the vortex flow and a difference between the centripetal force F2. , Fall in the resultant direction F of the sinking force F1.

【0016】この落下によって反転盤5と円筒部1の間
隙から粗流排出口3に向かって落下する粒子と、反転盤
5の円盤面6内に落下して外筒10または内筒11から
気体と一緒に吸引排出される粒子とに分級されるが、実
施例の構成によれば、分流排気構造8による吸引速度v
〔cm/s〕が、出口パイプ径断面で均一化されてお
り、而も安定しているため、前記式1による分級粒子径
δ〔cm〕が一定になる。
Due to this drop, the particles that drop from the gap between the reversing plate 5 and the cylindrical portion 1 toward the rough flow outlet 3 and the particles that fall into the disk surface 6 of the reversing plate 5 from the outer cylinder 10 or the inner cylinder 11 The particles are classified into particles that are sucked and discharged together with the particles.
[Cm / s] is uniform in the cross section of the diameter of the outlet pipe and is stable, so that the classified particle diameter δ [cm] according to the equation 1 becomes constant.

【0017】[0017]

【発明の効果】以上述べたように本発明によれば、サイ
クロン型の集塵装置において、分級室の軸芯位置に上壁
から内挿した微粒排出側構造が分流排気構造になり、パ
イプの断面方向で均一な流速を確保するようにしたこと
により、分級点が安定して分級精度が向上したものであ
り、本発明実施に伴う効果は極めて大きい。
As described above, according to the present invention, in the cyclone type dust collector, the fine particle discharge side structure inserted from the upper wall at the axial center position of the classification chamber becomes the split flow exhaust structure, By ensuring a uniform flow velocity in the cross-sectional direction, the classification point is stable and the classification accuracy is improved, and the effect of implementing the present invention is extremely large.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明に係るサイクロン型集塵装置の一実施例
を示す縦断面図である。
FIG. 1 is a vertical cross-sectional view showing an embodiment of a cyclone type dust collecting apparatus according to the present invention.

【図2】図1におけるII−II線断面図である。FIG. 2 is a sectional view taken along line II-II in FIG.

【図3】従来のサイクロン型集塵装置を示す縦断面図で
ある。
FIG. 3 is a vertical sectional view showing a conventional cyclone type dust collector.

【符号の説明】[Explanation of symbols]

1 円筒部 2 コーン部 3 粗粒排出口 4 分級室 5 反転盤 8 分流排気構造 9 渦流流入構造 10 外筒 11 内筒 12 微粒排出口 13 分流筒 14 円筒状分流室 15 含塵流体流入管 16 分流翼 17 含塵流体流入口 DESCRIPTION OF SYMBOLS 1 Cylindrical part 2 Cone part 3 Coarse grain discharge port 4 Classification chamber 5 Inversion board 8 Dividing flow exhaust structure 9 Eddy current inflow structure 10 Outer cylinder 11 Inner cylinder 12 Fine particle discharge port 13 Dividing cylinder 14 Cylindrical diversion chamber 15 Dust-containing fluid inflow pipe 16 Flow divider 17 Dust-containing fluid inlet

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 逆円錐状のコーン部の上端に円筒部を連
設し、下端に粗粒排出口を開口した分級室を構成すると
共に、該分級室に円錐台状の反転盤を架設し、分級室に
含塵流体流入管と微粒排出口を設けてなるサイクロン型
集塵装置において、 前記微粒排出口を、円筒部の上壁軸芯に位置して設けた
外筒に対して内筒を同芯状に内挿し、且つ分級室4に延
びる両筒の反転盤からの距離を外筒が内筒より長く構成
した分流排気構造とすると共に、前記含塵流体流入管を
前記外筒の外側に位置して同芯状に形成した円筒状分流
室の一側から含接線方向に突出し、該円筒状分流室の下
端部に位置して分流筒の内壁から内径方向に向かって渦
状に傾斜した複数の分流翼を突設した含塵流体流入口を
構成してなることを特徴とするサイクロン型集塵装置。
1. A classifying chamber in which a cylindrical part is continuously provided at an upper end of an inverted conical cone part and a coarse particle discharge port is opened at a lower end thereof, and a truncated cone-shaped reversing plate is installed in the classifying chamber. In a cyclone-type dust collector in which a dust-containing fluid inflow pipe and a fine particle discharge port are provided in a classification chamber, the fine particle discharge port is an inner cylinder with respect to an outer cylinder provided at an axial center of an upper wall of the cylindrical portion. Is inserted concentrically and the distance between both cylinders extending into the classification chamber 4 from the reversal plate is made longer so that the outer cylinder is longer than the inner cylinder, and the dust-containing fluid inflow pipe is connected to the outer cylinder. It is located on the outer side and protrudes in a tangential direction from one side of a concentric cylindrical flow dividing chamber, is positioned at the lower end of the cylindrical flow dividing chamber, and is spirally inclined from the inner wall of the flow dividing cylinder toward the inner diameter. Cyclone type dust collector characterized in that it comprises a dust-containing fluid inlet port formed by projecting a plurality of divided flow vanes
【請求項2】 前記分流排気構造が、直径dの外筒に対
して直径略0.7dの内筒を同芯状に内挿すると共に、
分級室に延びる両筒の反転盤からの距離が、外筒がLに
対して内筒は略1/2Lになるように構成したことを特
徴とする請求項1記載のサイクロン型集塵装置。
2. The split flow exhaust structure is configured such that an inner cylinder having a diameter of approximately 0.7d is concentrically inserted into an outer cylinder having a diameter d, and
2. The cyclone type dust collecting apparatus according to claim 1, wherein the distance between the two cylinders extending to the classification chamber from the reversing plate is such that the outer cylinder is L and the inner cylinder is approximately 1 / 2L.
JP35190291A 1991-12-13 1991-12-13 Cyclone type dust collector Expired - Lifetime JPH0691974B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP35190291A JPH0691974B2 (en) 1991-12-13 1991-12-13 Cyclone type dust collector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP35190291A JPH0691974B2 (en) 1991-12-13 1991-12-13 Cyclone type dust collector

Publications (2)

Publication Number Publication Date
JPH05161861A JPH05161861A (en) 1993-06-29
JPH0691974B2 true JPH0691974B2 (en) 1994-11-16

Family

ID=18420398

Family Applications (1)

Application Number Title Priority Date Filing Date
JP35190291A Expired - Lifetime JPH0691974B2 (en) 1991-12-13 1991-12-13 Cyclone type dust collector

Country Status (1)

Country Link
JP (1) JPH0691974B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0841085A1 (en) 1995-12-15 1998-05-13 Toyo Gijutsu Kogyo Co., Ltd. Cyclon type dust collector
CN1067295C (en) * 1996-09-04 2001-06-20 东洋技术工业株式会社 Cyclone dust collector

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6042628A (en) * 1996-11-12 2000-03-28 Toyo Gijutsu Kogyo Co., Ltd. Cyclone type dust collector
JP4640542B2 (en) * 2000-12-27 2011-03-02 有限会社吉工 Cyclone
CN100382895C (en) * 2003-05-13 2008-04-23 乐金电子(天津)电器有限公司 Cyclone duster
CN100375655C (en) * 2003-05-13 2008-03-19 乐金电子(天津)电器有限公司 Cyclone dust collector
CN100342979C (en) * 2003-05-13 2007-10-17 乐金电子(天津)电器有限公司 Cyclonic dust collector
CN100358639C (en) * 2003-05-13 2008-01-02 乐金电子(天津)电器有限公司 Cyclone duster
CN100342978C (en) * 2003-05-13 2007-10-17 乐金电子(天津)电器有限公司 Cyclone dust collector
CN100342977C (en) * 2003-05-13 2007-10-17 乐金电子(天津)电器有限公司 Cyclone duster
US8403149B2 (en) 2005-11-18 2013-03-26 Ricoh Company, Ltd. Cyclone classifier, flash drying system using the cyclone classifier, and toner prepared by the flash drying system
JP4732276B2 (en) * 2005-11-18 2011-07-27 株式会社リコー Cyclone classifier, airflow drying system and toner
JP4730286B2 (en) * 2006-11-24 2011-07-20 トヨタ自動車株式会社 Foreign matter removing apparatus and foreign matter removing method
GB2455535A (en) * 2007-12-12 2009-06-17 Prime Sourcing Ltd Cyclone chamber with vortex shield
CN102000636B (en) * 2010-09-06 2012-08-29 山东海韵生态纸业有限公司 Grass sheet impurity-removing method and equipment
JP5759341B2 (en) * 2011-11-15 2015-08-05 株式会社マキタ Cyclone equipment
CN113457859B (en) * 2020-03-30 2023-03-24 中国石油化工股份有限公司 Cyclone separator and solid-gas separation system
CN112942218B (en) * 2021-01-29 2023-02-10 厦门威迪思汽车设计服务有限公司 Subside gaseous purifier of formula and motor sweeper that has device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0841085A1 (en) 1995-12-15 1998-05-13 Toyo Gijutsu Kogyo Co., Ltd. Cyclon type dust collector
CN1067295C (en) * 1996-09-04 2001-06-20 东洋技术工业株式会社 Cyclone dust collector

Also Published As

Publication number Publication date
JPH05161861A (en) 1993-06-29

Similar Documents

Publication Publication Date Title
JPH0691974B2 (en) Cyclone type dust collector
US4756729A (en) Apparatus for separating dust from gases
US6596170B2 (en) Long free vortex cylindrical telescopic separation chamber cyclone apparatus
CA1084448A (en) Dynamic dense media separator
CA2687349C (en) Induced vortex particle separator
US3675401A (en) Cyclones to lessen fouling
US3850816A (en) Cyclone
US4409008A (en) Dust disposal cyclones
US3372532A (en) Dry separator
US4789476A (en) Cyclone separator with two separating zones and static guide mechanisms
US20050155916A1 (en) Cylindrical telescopic structure cyclone apparatus
US3636682A (en) Cyclone separator
JPH03224649A (en) Method and device for removing solid particle from fluid stream
GB675365A (en) Improvements in or relating to method of and apparatus for classifying particles
US5201422A (en) Classifier for powdery material
JPH0525717Y2 (en)
US20040069705A1 (en) Long free vortex, multi-compartment separation chamber cyclone apparatus
US3042202A (en) Cyclone classifier
JPH08299728A (en) Cyclone dust collector
JP2011045819A (en) Powder classifying apparatus
GB1401331A (en) Grader for fine-grained material
CN212119297U (en) Cyclone separator with particle material reverse cyclone gas flow control and multiple particle size distribution
JPH0663452A (en) Cyclone separator
RU2006291C1 (en) Cyclone
JPH09155239A (en) Coneless cyclone made as low as possible in height