WO2020103444A1 - 一种防液态行波旋转超声电机 - Google Patents

一种防液态行波旋转超声电机

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Publication number
WO2020103444A1
WO2020103444A1 PCT/CN2019/091681 CN2019091681W WO2020103444A1 WO 2020103444 A1 WO2020103444 A1 WO 2020103444A1 CN 2019091681 W CN2019091681 W CN 2019091681W WO 2020103444 A1 WO2020103444 A1 WO 2020103444A1
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WIPO (PCT)
Prior art keywords
sealing
hole
casing
stator
traveling wave
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PCT/CN2019/091681
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English (en)
French (fr)
Inventor
苏勋涛
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江苏紫金东方超声电机有限公司
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Application filed by 江苏紫金东方超声电机有限公司 filed Critical 江苏紫金东方超声电机有限公司
Publication of WO2020103444A1 publication Critical patent/WO2020103444A1/zh

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
    • H02N2/10—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing rotary motion, e.g. rotary motors
    • H02N2/16—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing rotary motion, e.g. rotary motors using travelling waves, i.e. Rayleigh surface waves
    • H02N2/166—Motors with disc stator
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K5/00—Casings; Enclosures; Supports
    • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
    • H02K5/10—Casings or enclosures characterised by the shape, form or construction thereof with arrangements for protection from ingress, e.g. water or fingers

Definitions

  • the invention relates to a traveling wave rotating ultrasonic motor, in particular to a traveling wave rotating ultrasonic motor with good anti-liquid invasion.
  • the traveling wave rotary ultrasonic motor is a micromotor, which uses the inverse piezoelectric effect of piezoelectric materials to excite the elastic body to generate micro-amplitude vibration in the ultrasonic frequency band, and converts it into the rotary motion of the rotor through the friction between the stator and the rotor.
  • New motor Because of its small size, light weight, low speed and large torque, low noise, fast response, high positioning accuracy, no electromagnetic interference and strong environmental adaptability. However, at present, once the existing ultrasonic motor is wetted by water or immersed in the liquid, a short circuit phenomenon will occur, resulting in the motor not working properly. Therefore, it is of great significance to develop an ultrasonic motor with high performance and good waterproof structure.
  • Object of the invention Aiming at the above-mentioned prior art, a liquid-proof traveling wave rotary ultrasonic motor is proposed to achieve a good anti-liquid invasion effect.
  • An anti-liquid traveling wave rotating ultrasonic motor including a stator base, a casing, a motor shaft, a stator, and a rotor, the rotor and a first bearing embedded in the stator, and a second bearing embedded in the casing
  • the casing is connected to the stator seat, the casing is provided with a power lead hole, the power lead hole is provided with a power lead, the piezoelectric ceramic of the stator is connected to the power lead, the machine
  • a first sealing ring is provided at the connection between the casing and the stator seat, and the first sealing ring is placed in the sealing ring mounting groove, and a sealing ring is provided inside the sealing ring mounting groove for completely sealing the first sealing ring
  • a skeleton seal ring is provided between the first bearing and the stator seat, the motor shaft passes through the skeleton seal ring, and the inner diameter of the skeleton seal ring is consistent with the outer diameter of the motor shaft.
  • the power lead extends outward from the power lead hole, the power lead hole is provided with a second sealing ring including the power lead, and the casing outside the power lead hole is provided with a sleeve joint
  • the inner diameter of the central through hole of the second sealing baffle is consistent with the outer diameter of the power supply lead.
  • the first sealing baffle is an annular baffle and is integrated with the stator seat, and the stepped structure at the bottom of the side wall of the cabinet and the stator seat form the sealing ring installation groove ,
  • the first baffle is in interference fit with the side wall of the cabinet.
  • a stepped hole is used in the center of the bottom of the stator seat, the minimum inner diameter of the stepped hole is greater than the outer diameter of the skeleton seal ring, an annular third sealing baffle is embedded at the stepped hole, and the motor shaft passes through After the third sealing baffle, the inner diameter of the central through hole of the third sealing baffle is consistent with the outer diameter of the motor shaft.
  • the power supply lead hole is a stepped hole, and the inner diameter of the large-diameter section of the stepped hole gradually shrinks from outside to inside in the axial direction, and two second seal rings are used in the large-diameter section of the stepped hole from outside to inside .
  • the invention uses multiple seals to prevent liquid intrusion at the connection between the casing and the stator base, the connection between the power lead and the power lead hole, and the connection between the motor shaft and the stator base, greatly improving the sealing of the traveling wave rotary ultrasonic motor.
  • the drawing is a schematic diagram of the structure of the anti-liquid traveling wave rotating ultrasonic motor of the present invention.
  • a liquid-proof traveling wave rotating ultrasonic motor includes a stator base 2, a casing 1, a motor shaft 3, a stator 4, a rotor 5, a rotor 5 and a first bearing 7 embedded in the stator base 2, and an embedded machine
  • the second bearing 6 of the shell 1 is connected in rotation, the stator 4 is fixed on the stator base 2, and the rotor 5 is mounted on the motor shaft 3.
  • the casing 1 is connected to the stator base 2.
  • the casing 1 is provided with a power supply lead hole.
  • the power supply lead hole is provided with a power supply lead 13.
  • the piezoelectric ceramic of the stator 4 is connected to the power supply lead 13.
  • connection between the casing 1 and the stator base 2 is provided with a first sealing ring 8
  • the first sealing ring 8 is placed in the sealing ring installation groove 15, and a first sealing ring is provided inside the sealing ring installation groove 15 8
  • the first sealing baffle 14 completely sealed in the sealing ring installation groove 15.
  • the first sealing baffle 14 is an annular baffle and is integrally connected with the stator seat 2.
  • the step structure at the bottom of the side wall of the casing 1 and the stator seat 2 form a seal ring mounting groove 15 and the first baffle 14 and the machine
  • the side wall of the shell 1 is in interference fit.
  • the first seal ring 8 as the connection between the casing 1 and the stator seat 2 forms a stepped structure, forming an integrated first seal baffle 14 to effectively seal the first seal ring 8 in the seal ring mounting groove 15 through an interference fit , That is, as the second sealing structure at the connection between the casing 1 and the stator seat 2, so as to realize the multiple sealing and liquid-proof effect.
  • a national seal ring 10 is provided between the first bearing 7 and the stator seat 2, the motor shaft 3 passes through the skeleton seal ring 10, the inner diameter of the skeleton seal ring 10 is consistent with the outer diameter of the motor shaft 3, and a stepped hole 16 is used in the center of the bottom of the stator seat 2 , The smallest inner diameter of the stepped hole 16 is larger than the outer diameter of the skeleton seal ring 10, a ring-shaped third sealing baffle 11 is embedded at the stepped hole 16, the third sealing baffle 11 is fixed by a structure such as a screw, and the motor shaft 3 passes through the third The inner diameter of the central through hole of the sealing baffle 11 and the third sealing baffle 11 is consistent with the outer diameter of the motor shaft 3.
  • the stepped hole 16 provides convenience for assembling the skeleton sealing ring 10 and the third sealing baffle 11.
  • the skeleton sealing ring 10 serves as the first sealing structure between the motor shaft 3 and the stator seat 2 and is embedded in the third sealing block of the stepped hole 16
  • the plate 11 serves as a second sealing structure, thereby forming a multi-sealing liquid-proof effect, which effectively prevents liquid from invading from the connection between the low-level shaft 3 and the stator base 2.
  • the power lead hole is a stepped hole.
  • the inner diameter of the large-diameter section of the stepped hole gradually shrinks from the outside to the inside in the axial direction.
  • the power lead 13 extends outward from the power lead hole.
  • the casing 1 outside the power lead hole is provided with a second sealing baffle 12 sleeved on the power lead 13, the inner diameter of the central through hole of the second sealing baffle is outside the power lead 13 The path is consistent.
  • the outer diameter of the power lead 13 is the same as the diameter of the small diameter section of the stepped hole, which plays the role of the first sealing: the stepped hole that gradually shrinks from outside to inside is matched with two second sealing rings 9 to effectively form a second sealing structure.
  • the second sealing baffle 12 provided on the outer side completely encloses the second sealing ring 9 in the power lead hole, forming a third sealing structure, that is, the precise cooperation of the above structures forms multiple seals at the power lead 13 and the power lead hole Liquid effect.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)

Abstract

一种防液态行波旋转超声电机，在机壳（1）与定子座（2）连接处、电源引线（13）与电源引线孔连接处以及电机轴（3）与定子座（2）连接处分别设有多重密封防液态侵入结构，多重密封防液态侵入结构均包括了密封环结构以及将密封环再次密封的密封挡板结构，通过精密的装配，大幅提高行波旋转超声电机的密封性。

Description

一种防液态行波旋转超声电机 技术领域
本发明涉及一种防行波旋转超声电机，尤其涉及一种具有良好防液体侵入的行波旋转超声电机。
背景技术
行波旋转超声电机是一种微电机，它利用压电材料的逆压电效应，激发弹性体在超声频段产生微幅振动，并通过定、转子之间的摩擦将其转换成转子的回转运动的新型电机。因其具有体积小、重量轻、低速大扭矩、噪声小、响应快、定位精度高、无电磁干扰和环境适应性强等优点。但是目前现有超声电机一旦被水淋湿或者浸入液体中就会出现短路的现象，导致电机不能正常工作。因此研制性能良好、结构及工艺简单的防水功能等级高的超声电机具有重大的意义。
发明内容
发明目的：针对上述现有技术，提出一种防液态行波旋转超声电机，实现良好的防液体侵入效果。
技术方案：一种防液态行波旋转超声电机，包括定子座、机壳、电机轴、定子、转子，所述转子与嵌入所述定子在的第一轴承以及嵌入所述机壳的第二轴承转动连接，所述机壳与定子座连接，所述机壳上设有电源引线孔，所述电源引线孔内设有电源引线，所述定子的压电陶瓷连接所述电源引线，所述机壳与定子座的连接处设有第一密封圈，所述的第一密封圈置于密封圈安装槽内，并在所述密封圈安装槽内侧设有用于将所述第一密封圈完全密封在所述密封圈安装槽内的第一密封挡板。
进一步的，所述第一轴承与所述定子座之间设有骨架密封圈，所述电机轴穿过所述骨架密封圈，所述骨架密封圈的内径与所述电机轴的外径一致。
进一步的，所述电源引线向外延伸出所述电源引线孔，所述电源引线孔内设有包括所述电源引线的第二密封圈，所述电源引线孔外侧的机壳上设有套接在所述电源引线上的第二密封挡板，所述第二密封挡板中央通孔的内径与所述电源引线外径一致。
进一步的，所述第一密封挡板为环状挡板并与所述定子座连成一体，所述机壳的侧壁底部的台阶结构与所述定子座连接处形成所述密封圈安装槽，所述第一挡板与所述机壳的侧壁与过盈配合。
进一步的，所述定子座底部中央使用阶梯孔，所述阶梯孔的最小内径大于所述骨架 密封圈外径，所述阶梯孔处嵌有环状的第三密封挡板，所述电机轴穿过所述第三密封挡板，所述第三密封挡板中央通孔的内径与所述电机轴外径一致。
进一步的，所述电源引线孔为阶梯孔，所述阶梯孔的大直径段的内径沿轴向由外向内逐渐收缩，在所述阶梯孔的大直径段由外向内使用两个第二密封圈。
有益效果：本发明在机壳与定子座连接处、电源引线与电源引线孔连接处以及电机轴与定子座连接处分别使用多重密封防液态侵入结构，大幅提高行波旋转超声电机的密封性。
附图说明
附图为本发明防液态行波旋转超声电机的结构示意图。
具体实施方式
下面结合附图对本发明的具体实施方式作进一步的详细说明。
如图1所示，一种防液态行波旋转超声电机，包括定子座2、机壳1、电机轴3、定子4、转子5、转子5与嵌入定子座2的第一轴承7以及嵌入机壳1的第二轴承6转动连接，定子4固定在定子座2上，转子5安装在电机轴3上。机壳1与定子座2连接，机壳1上设有电源引线孔，电源引线孔内设有电源引线13，定子4的压电陶瓷连接电源引线13。
其中，机壳1与定子座2的连接处设有第一密封圈8，第一密封圈8置于密封圈安装槽15内，并在密封圈安装槽15内侧设有用于将第一密封圈8完全密封在密封圈安装槽15内的第一密封挡板14。第一密封挡板14为环状挡板并与定子座2连成一体，机壳1的侧壁底部的台阶结构与定子座2连接处形成密封圈安装槽15，第一挡板14与机壳1的侧壁与过盈配合。第一密封圈8作为机壳1与定子座2连接处形成台阶型结构，形成一体式的第一密封挡板14通过过盈配合将第一密封圈8有效的密封在密封圈安装槽15内，即作为机壳1与定子座2连接处的第二道密封结构，从而实现多重密封防液态效果。
第一轴承7与定子座2之间设有国家密封圈10，电机轴3穿过骨架密封圈10，骨架密封圈10的内径与电机轴3外径一致，定子座2底部中央使用阶梯孔16，阶梯孔16的最小内径大于骨架密封圈10外径，阶梯孔16处嵌有环状的第三密封挡板11，第三密封挡板11通过螺钉等结构固定，电机轴3穿过第三密封挡板11，第三密封挡板11中央通孔的内径与所述电机轴3外径一致。阶梯孔16给装配骨架密封圈10以及第三密封挡板11提供便利，骨架密封圈10作为电机轴3与定子座2之间的第一道密封结构，嵌入到阶梯孔16的第三密封挡板11作为第二道密封结构，从而形成多重密封防液态效果，有效防止液体从低级轴3与 定子座2连接处侵入。
电源引线孔为阶梯孔，阶梯孔的大直径段的内径沿轴向由外向内逐渐收缩，电源引线13向外伸出电源引线孔，在阶梯看的大直径段由外向内设有包裹电源引线13的两个第二密封圈9.电源引线孔外侧的机壳1上设有套接在电源引线13上的第二密封挡板12，第二密封挡板中央通孔的内径与电源引线13外径一致。电源引线13的外径与阶梯孔的小直径段直径一致，起到第一道密封专作用：由外向内逐渐收缩的阶梯孔配合两个第二密封圈9，有效形成第二道密封结构，在外侧设置的第二密封挡板12将第二密封圈9完全封闭在电源引线孔内，形成第三道密封结构，即以上结构的精密配合形成电源引线13与电源引线孔处的多重密封防液态效果。
以上所述仅是本发明的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也应视。为本发明的保护范围

Claims (6)

  1. 一种防液态行波旋转超声电机，包括定子座(2)、机壳(1)、电机轴(3)、定子(4)、转子(5)，所述转子(5)与嵌入所述定子座(2)的第一轴承(7)以及嵌入所述机壳(1)的第二轴承(6)转动连接，所述机壳(1与)定子座(2连接，所述机壳(1)上设有电源引线孔，所述电源引线孔内设有电源引线(13)，所述定子(4)的压电陶瓷连接所述电源引线(13)，其特征在于:所述机壳(1)与定子座(2)的连接处设有第一密封圈(8)，所述第一密封圈(8)置于密封圈安装槽(15)内，并在所述密封圈安装槽(15)内侧设有用于将所述第一密封圈(8)完全密封在所述密封安装槽(15)内的第一密封圈挡板(14)。
  2. 根据权利要求1所述的防液态行波旋转超声电机，其特征在于：所述第一轴承(7)与所述定子座(2)之间设有骨架密封圈(10)，所述时电机轴(3)穿过所述骨架密封圈(10)，所述骨架密封圈(10)的内径与所述电机轴(3)外径研制一致。
  3. 根据权利要求1所述的防液态行波旋转超声电机，其特征在于：所述电源引线(13)向外延伸出电源引线孔，所述电源引线孔内设有包裹舒适电源引线(13)的第二密封圈(9)，所述电源引线孔外侧的机壳(1)上设有套接在所述电源引线(13)上的第二密封挡板(12)，所述第二密封挡板(12)这样通孔的内径与所述电源引线(13)外径一致。
  4. 根据权利要求1-3任一所述的防液态行波旋转超声电机，其特征在于：所述第一密封圈挡板(14)为环状挡板并与所述定子座(2)连城一体，所述机壳(1)侧壁底部的调节结构与所述定子座(2)连接处形成所述密封圈安装槽(15)，所述第一挡板(14)与所述机壳(1)的侧壁与过盈配合。
  5. 根据权利要求2所述的防液态行波旋转超声电机，其特征在于：所述定子座(2)底部这样设有阶梯孔(16)，所述阶梯孔(16)的最小内径大于所述骨架密封圈(10)外径，所述阶梯孔(16)处嵌有环状的第三密封挡板(11)，所述电机轴(3)穿过所述第三密封挡板(11)，所述第三密封挡板(11)中央通孔的内径与所述电机轴(3)外径一致。
  6. 根据权利要求3所述的防液态行波旋转超声电机，其特征在于：所述电源引线孔为阶梯孔，所述阶梯孔的大直径段的内径沿轴向内逐渐收缩，在所述阶梯孔的大直径段由外向内使用两个第二密封圈(9)。
PCT/CN2019/091681 2018-11-19 2019-06-18 一种防液态行波旋转超声电机 WO2020103444A1 (zh)

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