Patent Application
20070035073
The invention relates to electric motors and more particularly to an isolator for vibrationally isolating an electric motor.
Electric motors often produce vibrational energy in a frequency related to the harmonics of the number of windings within the motor. This vibrational energy can be transmitted to the structure of the component to which the electric motor is attached such that it causes the component to vibrate and emit noise. This can occur with automotive HVAC modules wherein the blower motor causes an objectionable tone noise to occur.
The invention provides an isolator for isolating vibration associated with an electric motor. The isolator includes a first body portion operable to be positioned adjacent to an external surface of a motor case of the electric motor. The isolator also includes a tongue integrally formed with and narrower than the first body portion. The tongue is operable to be received in a groove formed in the motor case. The isolator also includes a second body portion integrally formed with and wider than the tongue. The second body portion is operable to be disposed adjacent an internal surface of the motor case. As a result, at least a portion of the motor case of the electric motor is disposed between the first and second body portions.
Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
A plurality of different embodiments of the invention are shown in the Figures of the application. Similar features are shown in the various embodiments of the invention. Similar features have been numbered with a common reference numeral and have been differentiated by an alphabetic designation. Also, to enhance consistency, features in any particular drawing share the same alphabetic designation even if the feature is shown in less than all embodiments. Similar features are structured similarly, operate similarly, and/or have the same function unless otherwise indicated by the drawings or this specification. Furthermore, particular features of one embodiment can replace corresponding features in another embodiment unless otherwise indicated by the drawings or this specification.
Referring now to
The first body portion 14 defines a first width 46 and the tongue defines a second width 48 less than the first width 46. The tongue 20 is operable to be received in a groove 22 formed in the motor case 18. The isolator 10 also includes a second body portion 24 integrally formed with and wider than the tongue 20. The second body portion 24 defines a third width 50 greater than the second width 48. The second body portion 24 is operable to be disposed adjacent an internal surface 26 of the motor case 18. As a result, at least a portion of the motor case 18 of the electric motor 12 is disposed between the first and second body portions 14, 24.
As best shown in
As best shown in
The first body portion 14 extends a first length (such as first length 28a of the second exemplary embodiment shown in
The first body portion 14 extends the first length and has a first height 30. The first height 30 is variable along the first length. The first height 30 continuously increases along the first length from a first end 64 of the first body portion 14 to a second end 66. The first height 30 increases at first rate along a first portion 68 of the first length and increases at second rate greater than the first rate along a second portion 70 of the first length adjacent to the first portion 68. The change in the first height 30 along the first length can enhance assembly of the electric motor 12 in the housing 56. For example, the radially outward surface 72 of the first body portion 14 that is defined by the first height 30 can engage an inner surface 74 of the housing 56 to guide installing movement of the electric motor 12 relative to the housing 56. Also, the ramped, second portion 70 can accommodate irregularities in the surface 74 and/or manufacturing inconsistencies.
Referring now to
In the second exemplary embodiment of the invention, the first body portion 14a is longer than the second body portion 24a. The first body portion 14a extends a first length 28a and the second body portion 24a extends a second length 76a less than the first length 28a. Also, the tongue 20a is shorter than the first body portion 14a. During assembly of the isolator 10a to the motor case 18a, the second body portion 24a can be inserted in an aperture 78a. The aperture 78a communicates with the groove 22a. A protrusion 80a can extend radially inwardly from the first body portion 14a. The protrusion 80a can be shaped to correspond to the shape of the aperture 78a . During assembly of the isolator 10a to the motor case 18a, the protrusion 80a can snap into the aperture 78a when the tongue 20a reaches a bottom of the groove 22a to enhance the engagement between the isolator 10a and the motor case 18a.
Referring now to
In the third exemplary embodiment of the invention, a plurality of outer body portions, such as first body portion 14b, are integrally formed together. The second body portion 24b extends along a substantially annular path 32b corresponding to the internal surface of the motor case. A second tongue 34b is integrally formed with the second body portion 24b and is spaced from the tongue 20b along the annular path 32b. The second tongue 34b is narrower than the second body portion 24b and is operable to be received in a second groove formed in the motor case. A third body portion 38b is integrally formed with the second tongue 34b and is operable to be positioned adjacent to the external surface of the motor case of the electric motor. The third body portion 38b is shaped substantially similar to the first body portion 14b. The second body portion 24b also includes at least one aperture 44b operable to receive a portion of a brush card, such as brush card 42c as shown in
Referring now to
In the fourth exemplary embodiment of the invention, a plurality of outer body portions, such as first body portion 14c, are integrally formed together. The second body portion 24c extends along a substantially annular path, such as annular path 32b, corresponding to the internal surface of the motor case 18c. A second tongue 34c is integrally formed with the second body portion 24c and is spaced from the tongue 20c along the annular path. The second tongue 34c is narrower than the second body portion 24c and is operable to be received in a second groove 36c formed in the motor case 18c. A third body portion 38c is integrally formed with the second tongue 34c and is operable to be positioned adjacent to the external surface 16c of the motor case 18c of the electric motor 12c. The third body portion 38c is shaped substantially similar to the first body portion 14c. The second body portion 24c also includes at least one notch 40c operable to receive a portion of a brush card 42c whereby the second body portion 24c vibrationally isolates the brush card 42c from the motor case 18c.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
