JPH1076992A - Cavitation preventive structure of properller - Google Patents

Cavitation preventive structure of properller

Info

Publication number
JPH1076992A
JPH1076992A JP8235520A JP23552096A JPH1076992A JP H1076992 A JPH1076992 A JP H1076992A JP 8235520 A JP8235520 A JP 8235520A JP 23552096 A JP23552096 A JP 23552096A JP H1076992 A JPH1076992 A JP H1076992A
Authority
JP
Japan
Prior art keywords
propeller
water discharge
water
boss
discharge hole
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.)
Withdrawn
Application number
JP8235520A
Other languages
Japanese (ja)
Inventor
Yoshiki Hirahara
吉樹 平原
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yamaha Motor Co Ltd
Original Assignee
Yamaha Motor Co Ltd
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 Yamaha Motor Co Ltd filed Critical Yamaha Motor Co Ltd
Priority to JP8235520A priority Critical patent/JPH1076992A/en
Publication of JPH1076992A publication Critical patent/JPH1076992A/en
Withdrawn legal-status Critical Current

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  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

PROBLEM TO BE SOLVED: To prevent erosion without weakening strength of a propeller blade by opening a hole for water discharge on a propeller boss in the neighbourhood of a base part of the propeller blade on a rear surface side in the rotational direction of the propeller blade and communicating the hole for discharge to a small channel opened at a part higher inhydraulic pressure than its part. SOLUTION: A hollow part (small channel) 5 for weight reduction opened to its rear end part is formed into an annular shape around a propeller boss 29, and a hole 4 for water discharge 18 opened in the orthogona. direction on a shaft from the hollow part 5. The hole 4 for water discharge is formed upstream of a propeller blade 3 in the neighbourhood of a base part of the propeller blade 3 on a rear surface side in the rotational direction of the propeller blade 3. Thereafter, a water current 35 along a front surface 31 in the rotational direction is pressurized, and a water current 36 along a back surface 32 in the rotational direction is decompressed. Additionally, water between the propeller blade 3 and a fixed blade 61 is pressurized, the hollow part 5 is also pressurized through a clearance 50, and it is discharged to the side of an outer surface of the propeller boss 2 through the hole 4 for water discharge. Consequently, a decompression degree is reduced, and cavitation is prevented.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】この発明は、プロペラのキャ
ビテーション防止構造に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for preventing cavitation of a propeller.

【0002】[0002]

【従来の技術】一般に、船舶用などのプロペラにおいて
高速回転させるものではキャビテーションが発生するこ
とが避けられず、このキャビテーションによりプロペラ
翼の基部付近が侵食されることになる。これを防止する
ために、従来は例えば図6に示すような構造が採用され
ている。すなわち、プロペラシャフトに外嵌されるプロ
ペラボス20の外周部には複数枚のプロペラ翼30が一
体に取付けられてなり、このプロペラ翼30の基部には
回転方向の前面側から後面側に貫通する貫通穴40がそ
れぞれ形成されている。このためプロペラ翼30の回転
により、回転方向前面側から水が貫通穴40を通して回
転方向後面側に吐出され、回転方向後面側における減圧
部に水を供給することによりキャビテーションが発生す
るのを防止するようにしている。すなわち、プロペラの
回転によりプロペラ翼30の回転方向前面側は減圧さ
れ、回転方向後面側は加圧されることになり、回転方向
後面側ではプロペラ翼30の回転方向前端縁で気泡が発
生してそれがプロペラ翼30の基部に沿って回転方向後
方に流れ、その途中で気泡がつぶれることにより、衝撃
音および衝撃圧が発生して侵食(エロージョン)を生じ
させることになる。この現象を防止するために上記貫通
穴40が形成されている。
2. Description of the Related Art In general, cavitation inevitably occurs in propellers for boats and the like that rotate at high speed, and the cavitation erodes the vicinity of the base of the propeller blades. In order to prevent this, conventionally, for example, a structure as shown in FIG. 6 has been adopted. That is, a plurality of propeller blades 30 are integrally attached to the outer peripheral portion of the propeller boss 20 fitted on the propeller shaft, and the propeller blades 30 penetrate the base portion of the propeller blade 30 from the front side to the rear side in the rotation direction. Each of the through holes 40 is formed. Therefore, rotation of the propeller blades 30 causes water to be discharged from the front side in the rotation direction to the rear side in the rotation direction through the through holes 40, and prevents water from being supplied to the decompression unit on the rear side in the rotation direction, thereby preventing cavitation. Like that. That is, due to the rotation of the propeller, the front side in the rotation direction of the propeller blade 30 is depressurized, and the rear side in the rotation direction is pressurized. At the rear side in the rotation direction, air bubbles are generated at the front edge in the rotation direction of the propeller blade 30. It flows rearward in the rotational direction along the base of the propeller blade 30, and the bubbles are crushed on the way, thereby generating an impact sound and an impact pressure to cause erosion. In order to prevent this phenomenon, the through hole 40 is formed.

【0003】[0003]

【発明が解決しようとする課題】上記構成では、キャビ
テーションの発生を防止するという点ではとくに問題は
ないが、プロペラ翼30に貫通穴40を形成するため
に、この貫通穴40の部分に応力が集中することになっ
てプロペラ翼30の強度が低下することになり、このた
めプロペラの寿命が短くなるという問題がある。
In the above configuration, there is no particular problem in preventing the occurrence of cavitation. However, since the through hole 40 is formed in the propeller blade 30, stress is applied to the portion of the through hole 40. As a result, the strength of the propeller blades 30 is reduced, and the life of the propeller is shortened.

【0004】この発明は、このような従来の課題を解決
するためになされたものであり、プロペラ翼の強度を弱
めることなくキャビテーションによる侵食を確実に防止
することができるプロペラのキャビテーション防止構造
を提供するものである。
The present invention has been made to solve such a conventional problem, and provides a cavitation preventing structure for a propeller which can surely prevent erosion due to cavitation without reducing the strength of a propeller blade. Is what you do.

【0005】[0005]

【課題を解決するための手段】請求項1の発明は、プロ
ペラシャフトにプロペラボスが外嵌され、このプロペラ
ボスの外周部には複数枚のプロペラ翼が一体に取付けら
れてなり、このプロペラ翼の回転方向後面側におけるプ
ロペラ翼の基部近傍のプロペラボスにはそれぞれ水吐出
用穴がプロペラボスの表面に開口して形成され、この水
吐出用穴は、プロペラボスの他の部分またはその近傍で
あって水吐出用穴の部分より水圧の高い部分に開口して
いる小流路に連通しているものである。
According to a first aspect of the present invention, a propeller boss is externally fitted to a propeller shaft, and a plurality of propeller blades are integrally attached to an outer peripheral portion of the propeller boss. In the propeller boss near the base of the propeller blades on the rear side in the rotation direction of the propeller boss, a water discharge hole is formed by opening to the surface of the propeller boss, and this water discharge hole is formed in the other part of the propeller boss or in the vicinity thereof. There is a small flow path which is open to a portion where the water pressure is higher than the water discharge hole.

【0006】請求項1の発明では、水圧の高い部分の水
が小流路を通してプロペラボスのプロペラ翼の回転方向
後面側の減圧部に開口している水吐出用穴から吐出さ
れ、このため減圧部の減圧程度が軽減されてキャビテー
ションが発生するのが防止されることになる。しかもこ
の水吐出用穴は強度的に余裕のあるプロペラボスに形成
されており、プロペラ翼を強度的に弱めることがない。
According to the first aspect of the present invention, the water in the high water pressure portion is discharged from the water discharge hole which is opened through the small flow path to the pressure reducing portion on the rear side in the rotation direction of the propeller blades of the propeller boss. Cavitation is prevented from occurring due to reduction in the degree of pressure reduction in the section. In addition, the water discharge hole is formed in a propeller boss having a sufficient strength, so that the propeller blade is not weakened in strength.

【0007】請求項2の発明は、上記水吐出用穴は、プ
ロペラ翼の基部近傍であってプロペラ翼の回転方向前端
縁近傍に位置して、プロペラボスの外表面に開口してい
るものである。
According to a second aspect of the present invention, the water discharge hole is located near the base of the propeller blade and near the front edge in the rotation direction of the propeller blade, and is open to the outer surface of the propeller boss. is there.

【0008】請求項2の発明では、上記作用効果に加
え、水吐出用穴から、プロペラ翼の回転方向後面側の減
圧部に供給された水は、プロペラ翼の回転方向後面に沿
ってプロペラ翼の回転方向前端縁から後端縁に向かって
流れるために、プロペラ翼の回転方向後面のほぼ全域に
亘ってキャビテーションが発生するのを防止することが
できる。
According to the second aspect of the present invention, in addition to the above-described functions and effects, the water supplied from the water discharge hole to the pressure reducing portion on the rear side in the rotation direction of the propeller blades flows along the rear surface in the rotation direction of the propeller blades. Since the air flows from the front edge to the rear edge in the rotation direction of the propeller blade, cavitation can be prevented from occurring over substantially the entire rear surface of the propeller blade in the rotation direction.

【0009】請求項3の発明は、上記水吐出用穴は、プ
ロペラボスの前端部の水流上流向きの面に開口する流路
に連通しているものである。
According to a third aspect of the present invention, the water discharge hole communicates with a flow path that opens on a surface of the front end of the propeller boss facing the water flow upstream.

【0010】請求項3の発明では、上記作用効果に加
え、簡単な構成で水吐出用穴に水を確実に供給すること
ができる。
According to the third aspect of the invention, in addition to the above-described functions and effects, water can be reliably supplied to the water discharge hole with a simple configuration.

【0011】請求項4の発明は、上記プロペラボスの後
側にはプロペラシャフトを回転可能に支持する軸受部が
形成され、この軸受部の外周にはプロペラ翼からの旋回
流を整流する固定翼が形成され、上記プロペラボスの後
端面と軸受部の前端面との間には隙間が形成され、上記
プロペラボスには、その後端部に開口する中空部が形成
され、この中空部に上記隙間が連通し、上記水吐出用穴
は上記中空部に連通しているものである。
According to a fourth aspect of the present invention, a bearing portion for rotatably supporting a propeller shaft is formed on the rear side of the propeller boss, and a fixed blade for rectifying a swirling flow from the propeller blade on the outer periphery of the bearing portion. Is formed, a gap is formed between the rear end face of the propeller boss and the front end face of the bearing portion, and a hollow portion is formed in the propeller boss at the rear end portion, and the gap is formed in the hollow portion. And the water discharge hole communicates with the hollow part.

【0012】請求項4の発明では、上記作用効果に加
え、水吐出用穴に水を導く小流路を、重量軽減用の中空
部5および回転用の隙間を利用して形成しているので、
小流路を特別に形成する必要がない。
According to the fourth aspect of the present invention, in addition to the above-described functions and effects, a small flow path for guiding water to the water discharge hole is formed by utilizing the hollow portion 5 for reducing weight and the clearance for rotation. ,
There is no need to specially form a small channel.

【0013】[0013]

【発明の実施の形態】図1〜図3において、プロペラ1
はプロペラボス2の外周部に3枚のプロペラ翼3がそれ
ぞれ一体に螺旋状の傾斜で取付けられてなり、このプロ
ペラ1はジェット推進機のハウジング11内の流路12
中でプロペラシャフト10に取付けられている。すなわ
ち、プロペラシャフト10の後端部付近においてプロペ
ラボス2がプロペラシャフト10に外嵌され、その中心
穴に形成されたねじ部13でねじ結合されている。この
プロペラボス2には、その後端部に開口する重量軽減用
の中空部(小流路)5が環状に形成され、この中空部5
から軸に直角方向に外部に開口するように水吐出用穴4
が形成されている。この水吐出用穴4は、プロペラ翼3
の回転方向後面側(プロペラ1の進行方向前面側)にお
けるプロペラ翼3の基部近傍であって、プロペラ翼3の
上流側(回転方向前方側、すなわちプロペラ翼3の回転
方向前端縁33に近い側)に形成されている。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
The three propeller blades 3 are integrally mounted on the outer peripheral portion of the propeller boss 2 at a spiral inclination, and the propeller 1 is provided with a flow path 12 in a housing 11 of the jet propulsion device.
Mounted on the propeller shaft 10. That is, the propeller boss 2 is fitted around the propeller shaft 10 in the vicinity of the rear end of the propeller shaft 10 and is screwed together with the screw portion 13 formed in the center hole thereof. The propeller boss 2 is formed with a hollow portion (small flow path) 5 for reducing the weight, which is opened at the rear end thereof, in an annular shape.
Water discharge hole 4 so as to open to the outside in the direction perpendicular to the axis
Are formed. The water discharge hole 4 is provided with the propeller blade 3
Near the base of the propeller blade 3 on the rear side in the rotation direction (the front side in the traveling direction of the propeller 1), and on the upstream side of the propeller blade 3 (the front side in the rotation direction, that is, the side close to the front edge 33 in the rotation direction of the propeller blade 3). ) Is formed.

【0014】またプロペラ1の後方には上記ハウジング
11に連結部材16によって連結された軸受部6が形成
され、この軸受部6によってプロペラシャフト10の後
端部が回転可能に保持されている。すなわち、軸受部6
中にはプロペラシャフト10の後端部が貫通して前後一
対のベアリング62,63を介して回転可能に保持さ
れ、軸受部6の前端部にはパッキン64が配置され、こ
れによってベアリング62の部分に水が浸入しないよう
にシールされている。またこの軸受部6の外周部にはプ
ロペラ翼3からの旋回流を整流する固定翼61が周方向
に適宜の数形成され、また軸受部6の後端部にはプロペ
ラシャフト10の後端部を覆うとともに軸受部6の後流
を整流するための先細り形状のキャップ65が取付けら
れている。また上記プロペラボス2の後端面と軸受部6
の前端面との間にはプロペラボス2の回転が支障なく行
なわれるように隙間(小流路)50が形成されている。
A bearing 6 connected to the housing 11 by a connecting member 16 is formed behind the propeller 1, and the rear end of the propeller shaft 10 is rotatably held by the bearing 6. That is, the bearing 6
The rear end of the propeller shaft 10 penetrates and is rotatably held through a pair of front and rear bearings 62 and 63, and a packing 64 is disposed at the front end of the bearing 6, whereby a portion of the bearing 62 is provided. It is sealed to prevent water from entering. An appropriate number of fixed blades 61 for rectifying the swirling flow from the propeller blades 3 are formed on the outer peripheral portion of the bearing portion 6 in the circumferential direction, and the rear end of the propeller shaft 10 is provided at the rear end of the bearing portion 6. And a tapered cap 65 for rectifying the wake of the bearing 6. The rear end face of the propeller boss 2 and the bearing 6
A gap (small flow path) 50 is formed between the front end face and the front end face so that the rotation of the propeller boss 2 is performed without any trouble.

【0015】図4および図5はこの発明の別の実施形態
を示し、プロペラシャフト10に外嵌されたプロペラボ
ス29には上記同様に外周部にプロペラ翼3が一体に取
付けられ、プロペラボス29の前端部には水流上流向き
の前端面28が形成され、またこのプロペラボス29の
後端部には整流用のキャップ65が取付けられている。
そしてこのプロペラボス29の外周面には、水吐出用穴
44が形成され、この水吐出用穴44に連通する小流路
41の他端部は上記プロペラボスの前端面28に開口し
ている(開口部42)。この水吐出用穴44も、上記同
様にプロペラ翼3の回転方向後面側におけるプロペラ翼
3の基部近傍であって、プロペラ翼3の回転方向前端縁
近傍に形成されている。
FIGS. 4 and 5 show another embodiment of the present invention, in which the propeller blades 3 externally fitted to the propeller shaft 10 are integrally attached with the propeller blades 3 on the outer periphery in the same manner as described above. A water flow upstream-facing front end surface 28 is formed at a front end of the propeller boss 29, and a rectifying cap 65 is attached to a rear end of the propeller boss 29.
A water discharge hole 44 is formed on the outer peripheral surface of the propeller boss 29, and the other end of the small flow path 41 communicating with the water discharge hole 44 is open to the front end surface 28 of the propeller boss. (Opening 42). The water discharge hole 44 is also formed near the base of the propeller blade 3 on the rear side in the rotation direction of the propeller blade 3 and near the front end edge in the rotation direction of the propeller blade 3 in the same manner as described above.

【0016】上記図1〜図3の構成において、プロペラ
1が回転すると流路12中の水はプロペラ翼3の回転方
向前面側で加圧されつつ後方に旋回しながら送られ、ま
た回転方向後面側は減圧される。すなわち、図3仮想線
に示すように、プロペラ翼3はいわゆる翼形断面形状に
形成され、回転方向前面31は平坦面に形成され、回転
方向後面32は凸曲面に形成されている。そして回転方
向前面31に沿う水流35は加圧され、回転方向後面3
2に沿う水流36は減圧されることになる。固定翼61
の部分に送られた水は固定翼61によって整流されてさ
らに流路12中を後方に送られる。このプロペラ翼3と
固定翼61との間では流れ方向が変えられるために水は
加圧されることになり、その水は隙間50を通して中空
部50中に供給されて中空部5も加圧状態となる。そし
て水吐出用穴4の先端が開口してプロペラ翼3の回転方
向後面側は減圧されているため中空部5中の水は水吐出
用穴4を通してプロペラボス2の外面側に吐出され、減
圧部の減圧程度が軽減されてキャビテーションが発生す
るのが防止されることになる。しかもこの水吐出用穴4
は強度的に余裕のあるプロペラボス2に形成され、プロ
ペラ翼3を強度的に弱めることがない。また重量軽減用
の中空部5および回転用の隙間50を利用して水吐出用
穴4に水を供給する小流路を形成している。このため水
吐出用穴4に水を導く小流路を特別に形成する必要がな
い。
In the configuration shown in FIGS. 1 to 3, when the propeller 1 rotates, the water in the flow path 12 is sent while rotating backward while being pressurized on the front side in the rotation direction of the propeller blades 3, and the rear surface in the rotation direction. The side is depressurized. That is, as shown by the phantom line in FIG. 3, the propeller blade 3 is formed in a so-called airfoil cross-sectional shape, the front surface 31 in the rotational direction is formed as a flat surface, and the rear surface 32 in the rotational direction is formed as a convex curved surface. Then, the water flow 35 along the rotation direction front surface 31 is pressurized, and the water direction 35
The water stream 36 along 2 will be depressurized. Fixed wing 61
The water sent to the portion (1) is rectified by the fixed blades 61 and further sent backward in the flow path 12. Since the flow direction is changed between the propeller blade 3 and the fixed blade 61, the water is pressurized. The water is supplied into the hollow portion 50 through the gap 50, and the hollow portion 5 is also pressurized. Becomes Since the tip of the water discharge hole 4 is open and the rear side in the rotational direction of the propeller blade 3 is depressurized, the water in the hollow portion 5 is discharged to the outer surface side of the propeller boss 2 through the water discharge hole 4 and decompressed. Cavitation is prevented from occurring due to reduction in the degree of pressure reduction in the section. Moreover, this water discharge hole 4
Is formed in the propeller boss 2 having a sufficient strength, and does not weaken the propeller blade 3 in strength. A small flow path for supplying water to the water discharge hole 4 is formed by utilizing the hollow portion 5 for reducing the weight and the gap 50 for rotation. For this reason, it is not necessary to specially form a small flow channel for guiding water to the water discharge hole 4.

【0017】なお、中空部5中の水が水吐出用穴4を通
して逃がされるために、この部分の水圧が減少すること
になり、このためパッキン64を通してベアリング62
へ水が浸入するのを防止しやすくなるという利点もあ
る。
Since the water in the hollow portion 5 is released through the water discharge hole 4, the water pressure in this portion is reduced.
There is also an advantage that it is easy to prevent water from entering.

【0018】また図4および図5の実施形態では、水は
プロペラの回転によりプロペラ翼3の回転方向前面側で
加圧されつつ後方に旋回しながら送られ、またプロペラ
翼3の回転方向後面側は減圧される点は上記同様であ
る。プロペラボス29よりも前方では水はプロペラシャ
フト10の軸方向に流れるために前端面28には直角に
当たることになり、このためプロペラボス29の前端面
28は加圧され、これによって水が開口部42から送り
込まれて水吐出用穴44から吐出される。そしてこの水
吐出用穴44は上記同様にプロペラ翼3の回転方向後面
側の減圧部に開口しているために、減圧部の減圧程度が
軽減されてキャビテーションが発生するのが防止される
ことになる。この構成では上記作用効果に加え、簡単な
構成で水吐出用穴44に水を確実に供給することができ
る。
In the embodiment of FIGS. 4 and 5, the water is sent while being rotated rearward while being pressurized by the rotation of the propeller on the front side in the rotation direction of the propeller blades 3, and on the rear side in the rotation direction of the propeller blades 3. Is similar to the above in that the pressure is reduced. In front of the propeller boss 29, the water flows in the axial direction of the propeller shaft 10, so that the water hits the front end face 28 at a right angle, and the front end face 28 of the propeller boss 29 is pressurized. The water is discharged from the water discharge hole 42 and discharged from the water discharge hole 44. Since the water discharge hole 44 is open to the pressure reducing portion on the rear surface side in the rotation direction of the propeller blade 3 in the same manner as described above, the degree of pressure reduction in the pressure reducing portion is reduced, thereby preventing the occurrence of cavitation. Become. With this configuration, in addition to the above-described functions and effects, water can be reliably supplied to the water discharge hole 44 with a simple configuration.

【0019】[0019]

【発明の効果】請求項1の発明では、水圧の高い部分の
水が小流路を通してプロペラボスのプロペラ翼の回転方
向後面側の減圧部に開口している水吐出用穴から吐出さ
れ、このため減圧部の減圧程度が軽減されてキャビテー
ションが発生するのが防止されることになる。しかもこ
の水吐出用穴は強度的に余裕のあるプロペラボスに形成
されており、プロペラ翼を強度的に弱めることがない。
According to the first aspect of the present invention, the water in the high water pressure portion is discharged from the water discharge hole which is opened through the small flow path to the pressure reducing portion on the rear side in the rotation direction of the propeller blades of the propeller boss. Therefore, the degree of decompression of the decompression unit is reduced, thereby preventing the occurrence of cavitation. In addition, the water discharge hole is formed in a propeller boss having a sufficient strength, so that the propeller blade is not weakened in strength.

【0020】請求項2の発明では、上記作用効果に加
え、水吐出用穴から、プロペラ翼の回転方向後面側の減
圧部に供給された水は、プロペラ翼の回転方向後面に沿
ってプロペラ翼の回転方向前端縁から後端縁に向かって
流れるために、プロペラ翼の回転方向後面のほぼ全域に
亘ってキャビテーションが発生するのを防止することが
できる。
According to the second aspect of the present invention, in addition to the above-described functions and effects, the water supplied from the water discharge hole to the pressure reducing portion on the rear side in the rotational direction of the propeller blades flows along the rear side in the rotational direction of the propeller blades. Since the air flows from the front edge to the rear edge in the rotation direction of the propeller blade, cavitation can be prevented from occurring over substantially the entire rear surface of the propeller blade in the rotation direction.

【0021】請求項3の発明では、上記作用効果に加
え、簡単な構成で水吐出用穴に水を確実に供給すること
ができる。
According to the third aspect of the present invention, in addition to the above-described functions and effects, water can be reliably supplied to the water discharge hole with a simple configuration.

【0022】請求項4の発明では、上記作用効果に加
え、水吐出用穴に水を導く小流路を、重量軽減用の中空
部5および回転用の隙間を利用して形成しているので、
小流路を特別に形成する必要がない。
According to the fourth aspect of the present invention, in addition to the above-mentioned functions and effects, a small flow path for guiding water to the water discharge hole is formed by utilizing the hollow portion 5 for reducing the weight and the gap for rotation. ,
There is no need to specially form a small channel.

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

【図1】この発明の実施形態を示す斜視図である。FIG. 1 is a perspective view showing an embodiment of the present invention.

【図2】図1の正面図である。FIG. 2 is a front view of FIG.

【図3】図1のプロペラを推進機へ取付けた状態の縦断
面図である。
FIG. 3 is a longitudinal sectional view showing a state where the propeller of FIG. 1 is attached to a propulsion device.

【図4】この発明の別の実施形態を示す斜視図である。FIG. 4 is a perspective view showing another embodiment of the present invention.

【図5】図4の部分断面側面図である。FIG. 5 is a partial sectional side view of FIG. 4;

【図6】(a)は従来のプロペラの斜視図、(b)は
(a)の縦断面図である。
6A is a perspective view of a conventional propeller, and FIG. 6B is a longitudinal sectional view of FIG.

【符号の説明】[Explanation of symbols]

1 プロペラ 2,29 プロペラボス 3 プロペラ翼 4,44 水吐出用穴 5 中空部(小流路) 10 プロペラシャフト 12 流路 41 小流路 42 小流路の開口部 50 隙間 DESCRIPTION OF SYMBOLS 1 Propeller 2, 29 Propeller boss 3 Propeller blade 4, 44 Water discharge hole 5 Hollow part (small channel) 10 Propeller shaft 12 Channel 41 Small channel 42 Small channel opening 50 Gap

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】 プロペラシャフトにプロペラボスが外嵌
され、このプロペラボスの外周部には複数枚のプロペラ
翼が一体に取付けられてなり、このプロペラ翼の回転方
向後面側におけるプロペラ翼の基部近傍のプロペラボス
にはそれぞれ水吐出用穴がプロペラボスの表面に開口し
て形成され、この水吐出用穴は、プロペラボスの他の部
分またはその近傍であって水吐出用穴の部分より水圧の
高い部分に開口している小流路に連通していることを特
徴とするプロペラのキャビテーション防止構造。
1. A propeller boss is externally fitted to a propeller shaft, and a plurality of propeller blades are integrally attached to an outer peripheral portion of the propeller boss, and a vicinity of a base of the propeller blade on a rear surface side in a rotation direction of the propeller blade. In each of the propeller bosses, a water discharge hole is formed by opening on the surface of the propeller boss, and this water discharge hole is located at or near another part of the propeller boss and has a higher water pressure than the water discharge hole. A structure for preventing cavitation of a propeller, characterized in that it communicates with a small flow path that opens to a high part.
【請求項2】 上記水吐出用穴は、プロペラ翼の基部近
傍であってプロペラ翼の回転方向前端縁近傍に位置し
て、プロペラボスの外表面に開口していることを特徴と
する請求項1記載のプロペラのキャビテーション防止構
造。
2. The propeller boss according to claim 2, wherein the water discharge hole is located near the base of the propeller blade and near the front edge in the rotation direction of the propeller blade, and is open to the outer surface of the propeller boss. 2. The structure for preventing cavitation of a propeller according to claim 1.
【請求項3】 上記水吐出用穴は、プロペラボスの前端
部の水流上流向きの面に開口する流路に連通しているこ
とを特徴とする請求項1記載のプロペラのキャビテーシ
ョン防止構造。
3. The structure for preventing cavitation of a propeller according to claim 1, wherein the water discharge hole communicates with a flow path opened on a surface of the front end of the propeller boss facing the water flow upstream.
【請求項4】 上記プロペラボスの後側にはプロペラシ
ャフトを回転可能に支持する軸受部が形成され、この軸
受部の外周にはプロペラ翼からの旋回流を整流する固定
翼が形成され、上記プロペラボスの後端面と軸受部の前
端面との間には隙間が形成され、上記プロペラボスに
は、その後端部に開口する中空部が形成され、この中空
部に上記隙間が連通し、上記水吐出用穴は上記中空部に
連通していることを特徴とする請求項1記載のプロペラ
のキャビテーション防止構造。
4. A bearing portion for rotatably supporting a propeller shaft is formed on a rear side of the propeller boss, and a fixed blade for rectifying a swirling flow from the propeller blade is formed on an outer periphery of the bearing portion. A gap is formed between the rear end face of the propeller boss and the front end face of the bearing portion, and the propeller boss has a hollow portion formed at the rear end thereof, and the gap communicates with the hollow portion. The structure for preventing cavitation of a propeller according to claim 1, wherein the water discharge hole communicates with the hollow portion.
JP8235520A 1996-09-05 1996-09-05 Cavitation preventive structure of properller Withdrawn JPH1076992A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP8235520A JPH1076992A (en) 1996-09-05 1996-09-05 Cavitation preventive structure of properller

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP8235520A JPH1076992A (en) 1996-09-05 1996-09-05 Cavitation preventive structure of properller

Publications (1)

Publication Number Publication Date
JPH1076992A true JPH1076992A (en) 1998-03-24

Family

ID=16987202

Family Applications (1)

Application Number Title Priority Date Filing Date
JP8235520A Withdrawn JPH1076992A (en) 1996-09-05 1996-09-05 Cavitation preventive structure of properller

Country Status (1)

Country Link
JP (1) JPH1076992A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101225147B1 (en) 2010-06-29 2013-01-22 삼성중공업 주식회사 Boss cap and ship having the same
CN108891566A (en) * 2018-06-27 2018-11-27 长航集团芜湖江东船厂有限公司 Roll-on/roll-off vessel for vehicle propeller
RU2750507C1 (en) * 2020-09-02 2021-06-29 Александр Николаевич Уткин Floating propeller
CN115071937A (en) * 2022-07-06 2022-09-20 湘潭大学 Underwater driving device without bearing

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101225147B1 (en) 2010-06-29 2013-01-22 삼성중공업 주식회사 Boss cap and ship having the same
CN108891566A (en) * 2018-06-27 2018-11-27 长航集团芜湖江东船厂有限公司 Roll-on/roll-off vessel for vehicle propeller
RU2750507C1 (en) * 2020-09-02 2021-06-29 Александр Николаевич Уткин Floating propeller
CN115071937A (en) * 2022-07-06 2022-09-20 湘潭大学 Underwater driving device without bearing
CN115071937B (en) * 2022-07-06 2024-04-02 湘潭大学 Bearingless underwater driving device

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Effective date: 20031202