Patent Application
20060086564
1. Field of the Invention
The present invention generally relates to a resonator for attenuating acoustic pressure pulsations from an engine.
2. Description of Related Art
Internal combustion engines produce undesirable air induction noise in the form of acoustic pressure pulsations. This induction noise depends on the engine configuration and engine speed and is caused by a pressure wave that travels from the inlet valve towards the inlet of the air induction system.
Resonators for attenuating acoustic pressure pulsations in automotive applications are well known. The induction noise may be reduced by reflecting a portion the noise wave 180° out of phase with the noise wave. As such, Helmholtz type resonators have been used to attenuate the noise wave generated from the air intake event.
Additionally and more recently, resonators have been developed that change the volume of the resonator to adjust for varying frequencies of the noise wave, as engine speed changes. Previous designs, however, have not provided a wide enough frequency range to attenuate the various noise frequencies produced by the engine.
In view of the above, it is apparent that there exists a need for an improved resonator having broader flexibility to attenuate various noise frequencies of the engine.
In satisfying the above need, as well as, overcoming the enumerated drawbacks and other limitations of the related art, the present invention provides a resonator for attenuating pressure pulses. Walls of the housing of the resonator form a cavity with first and second openings. A divider is located in the cavity and cooperates with the housing to form first and second chambers. The shape of the housing and orientation of the divider is such that rotation of the divider changes the volume of the first and second chambers.
Located between the first opening and the first chamber is a first neck and a second neck located between the second opening and the second chamber. The first and second necks are configured to change neck length based on the rotational position of the divider.
In another aspect of the present invention, the first neck has a cross-sectional area smaller than the cross-sectional area of the first chamber. Similarly, the second neck has a smaller cross-sectional area than the cross-sectional area of the second chamber.
In yet another aspect of the present invention, to change the rotational position of the divider based on engine speed, an actuator is connected to the divider. Further, a first valve is in communication with the first neck and a second valve is in communication with the second neck. Each valve being configured to change the open area within their respective necks based on the engine speed.
Further objects, features and advantages of this invention will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification.
Referring now to
The resonator housing 12 has walls 13 that form a main cavity 14. Located within the cavity 14 and separating the cavity 14 into a first chamber 20 and a second chamber 22 is a divider 16. A seal 18, of a compressible durable material, is preferably attached to the divider 16 between the divider 16 and the wall 13 of the resonator housing 12. The seal 18 serves to separate the first and second chamber 20, 22 preventing the transmission of pressure pulsations between the first and second chamber 20, 22.
A first opening 24 in the resonator housing 12 allows the first chamber 20 to receive pressure pulsations for attenuation. Extending through the first opening 24 and into the first chamber 20 is a first neck 26. A first portion 30 of the first neck 26 is stationary, while a second portion 32 of the first neck 26 may extend from or retract over the first portion 30 of the first neck 26.
The divider 16 is rotatable to change the volume of the first and second chambers 20, 22. As shown, the divider 16 changes the volume of the first chamber 20 in proportion to a change in the volume of the second chamber 22. In addition, a linkage 34 is connected between the divider 16 and the second portion 32 of the first neck 26. The linkage 34 is attached to both the first neck 26 and the divider 16, and configured to change the neck length of the first neck 26 based on an angular position of the divider 16.
A first valve 28 is located in the first neck 26 and is configured to provide a variable area within the neck 26 to control acoustic wave propagation into the first chamber 20. The first valve 28 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the first chamber 20. Further, the first valve 28 is in communication with a controller 58 that controls the position of the first valve 28, via a proportional solenoid or motor, based on the engine speed.
A second opening 44 in the resonator housing 12 allows the second chamber 22 to receive pressure pulsations for attenuation. Extending through the second opening 44 and into the first chamber 22 is a second neck 46. A first portion 50 of the second neck 46 is stationary, while a second portion 52 of the second neck 46 may extend from or retract over the first portion 50 of the second neck 46.
Connected between the divider 16 and the second portion 52 of the second neck 46 is a linkage 54 that is configured to change the neck length of the second neck 46 based on an angular position of the divider 16. A second valve 48 is located in the neck 46 and is configured to provide a variable area within the neck 46 to control acoustic wave propagation into the second chamber 22. The second valve 48 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the first chamber 22. Further, the second valve 48 is in communication with the controller 58, which controls the second valve 48, via a proportional solenoid or motor, based on the engine speed.
To vary the angular position of the divider 16, a motor 56 is coupled to the divider 16 to rotationally manipulate the divider 16. A controller 58 is configured to drive the motor 56, thereby manipulating the angular position of the divider 16, based on one or many vehicle parameters. Specifically, the controller 58 may manipulate the angular position of the divider 16 based on the speed or revolutions per minute of the vehicle's engine. The motor 56 includes an output shaft 60 that includes gear teeth to engage teeth of a gear 62 coupled to a shaft 64 supporting and manipulating the divider 16. Alternative connections between the motor 56 and the divider 16 to control the angular position of the divider 16, may include various gearing configurations, multiple gear sets, direct drives, drive belts, chains and rollers to transfer torque.
Now referring to
The first resonator 70 has a first divider 78 that forms a first and second volume. A first neck 82 communicates with the first volume and a second neck 83 communicates with the second volume. A first motor 84 is coupled to the first divider 78 to rotate the first divider 78 thereby adjusting each of the first and second volume to change frequency attenuation characteristics.
A first portion 90 of the first neck 82 is stationary, while a second portion 92 of the first neck 82 may extend from or retract over the first portion 90 of the first neck 82. In addition, a first linkage 94 is connected between the first divider 78 and the second portion 92 of the first neck 82. The first linkage 94 is configured to change the neck length of the first neck 82 based on an angular position of the first divider 78.
A first valve 96 is located in the first neck 82 and is configured to provide a variable area within the first neck 82 to control acoustic wave propagation into the first chamber. The first valve 96 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the first chamber. Further, the first valve 96 is in communication with a controller 98 that controls the position of the first valve 96, via a proportional solenoid or motor, based on the engine speed.
A first portion 100 of the second neck 83 is stationary, while a second portion 102 of the second neck 83 may extend from or retract over the first portion 100 of the second neck 83. In addition, a second linkage 104 is connected between the first divider 78 and the second portion 102 of the second neck 83. The second linkage 104 is configured to change the neck length of the second neck 83 based on an angular position of the first divider 78.
A second valve 106 is located in the second neck 83 and is configured to provide a variable area within the second neck 83 to control acoustic wave propagation into the second chamber. The second valve 106 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the second chamber. Further, the second valve 106 is in communication with controller 98 that controls the position of the second valve 106, via a proportional solenoid or motor, based on the engine speed.
The second resonator 72 has a second divider 80 that forms a third and fourth volume. A third neck 86 communicates with the third volume and a fourth neck 87 communicates with the fourth volume. A second motor 88 is coupled to the second divider 80 to rotate the second divider 80 thereby adjusting each of the third and fourth volume to change frequency attenuation characteristics.
A first portion 110 of the third neck 86 is stationary, while a second portion 112 of the third neck 86 may extend from or retract over the first portion 110 of the third neck 86. In addition, a third linkage 114 is connected between the second divider 80 and the second portion 112 of the third neck 86. The third linkage 114 is configured to change the neck length of the third neck 86 based on an angular position of the second divider 80.
A third valve 116 is located in the third neck 86 and is configured to provide a variable area within the third neck 86 to control acoustic wave propagation into the third chamber. The third valve 116 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the third chamber. Further, the third valve 116 is in communication with controller 98 that controls the position of the third valve 116, via a proportional solenoid or motor, based on the engine speed.
A first portion 120 of the fourth neck 87 is stationary, while a second portion 122 of the fourth neck 87 may extend from or retract over the first portion 120 of the fourth neck 87. In addition, a fourth linkage 124 is connected between the second divider 80 and the second portion 122 of the fourth neck 87. The fourth linkage 124 is configured to change the neck length of the fourth neck 87 based on an angular position of the second divider 80.
A fourth valve 126 is located in the fourth neck 87 and is configured to provide a variable area within the fourth neck 87 to control acoustic wave propagation into the fourth chamber. The fourth valve 126 may open or close to any position thereby changing the cross-sectional area available for pressure pulsations to enter the fourth chamber. Further, the fourth valve 126 is in communication with controller 98 that controls the position of the fourth valve 126, via a proportional solenoid or motor, based on the engine speed.
As a person skilled in the art will readily appreciate, the above description is meant as an illustration of implementation of the principles this invention. This description is not intended to limit the scope or application of this invention in that the invention is susceptible to modification, variation and change, without departing from spirit of this invention, as defined in the following claims.
