Internal-combustion engines – Intake manifold – Manifold tuning – balancing or pressure regulating means
Reexamination Certificate
2000-03-13
2001-03-27
Kamen, Noah P. (Department: 3747)
Internal-combustion engines
Intake manifold
Manifold tuning, balancing or pressure regulating means
C181S229000
Reexamination Certificate
active
06205968
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to an air intake system, especially for use as an air intake duct of an internal combustion engine.
Air intake systems for internal combustion engines are provided with shunt resonators especially in the area of the intake tube in order to suppress the air intake noise. In the simplest case these shunt resonators consist of a resonator chamber and a resonator neck which connects the resonator chamber to the intake tube. This basic form of the shunt resonator can be varied according to the particular application. It is conceivable to have several necks which have different lengths to make it possible to dampen air intake noises of different frequencies. The resonator chamber can have almost any desired shape.
A disadvantage in the use of shunt resonators is the space they require in the area of the air intake tube. This must be provided in the motor compartment, which is difficult due to the restricted space in the motor compartment. An approach to the solution of the problem is to be found, for example, in DE 3842248 A1. A resonator is proposed which is integrated into the housing of the air intake system. In this manner it is possible to use the dead space present in the housing as a resonator chamber. Therefore there is no need to provide additional installation space in the motor compartment.
The above-described resonator chamber must, however, be given attention structurally when establishing the configuration of the intake tube housing. It is disadvantageous that the resonator described cannot be used to improve the acoustics of an existing intake tube if the results in regard to the intake noise of the intake tube are unsatisfactory. In such a situation there often is no more room in the motor compartment for a shunt resonator, since the development of the vehicle in question is nearly completed. Thus an expensive new design may be necessary in the intake tube area.
SUMMARY OF THE INVENTION
The object of the invention is to provide a Helmholz resonator which requires little space for its installation and can also be inserted subsequently into an already existing intake tube structure. At the same time either special frequencies of the intake noise are to be damped or a broad-band damping is to be achieved.
ADVANTAGES OF THE INVENTION
The object is achieved in accordance with the invention in that an internal structure is placed in the interior of the intake tube and fastened there. This internal structure forms together with the walls of the intake tube a resonator chamber which must have at least one opening into the interior volume of the intake tube. Such an internal structure requires no additional installation space in the motor compartment. Furthermore, the possibility of retrofitting is an advantage. Above all this is easy to accomplish in air intake tubes which are manufactured by the multiple shell technique. Likewise, however, such an internal structure can be installed through the inlet and outlet openings of the intake tube. At the same time the shape of the intake tube need not be changed or need only be changed to an insubstantial extent. If the internal structure has been glued in, for example, it need only be adapted to a certain contour area of the intake tube. Advantageously, the internal structure can be configured in such a way that, after installation in the intake tube, it produces several resonator chambers of different volume. By this means different frequencies can be damped at points of concentration in the intake area.
One practical variant of the invention envisions installation of the internal structure in the interior of the air intake tube. It is arranged ahead of the air intake ducts to the cylinders. Therefore the noise damping acts on all of the air intake ducts of the air intake tube.
According to one practical embodiment of the internal structure, it is constructed of a flat component, e.g., a perforated plate, and spacers. The resonator chamber is accordingly produced between the perforated plate and the wall of the intake tube. It is advantageous in this case that the internal structure can be produced from simple semi-finished products. This leads to an economical improvement in the case of small series, e.g., in the tuning area.
An alternative variant of the internal structure envisions configuring it as an insert. It can be made in one piece with a positive influence on economy in large series production.
In accordance with a further embodiment of the invention the internal structure can have areas of differing wall thickness. If a plurality of openings are provided in an internal structure, then different neck lengths will result for the shunt resonator. The positive effect of this embodiment is a broad-band damping of the air intake noise.
On condition that the internal structure and the air intake tube are composed of the same material, the internal structure can also be welded into the air intake tube. This applies in particular to synthetic resin intake tubes, however it is also conceivable for metal intake tubes. A synthetic resin insert can be installed especially by ultrasonic welding methods. In any case other welding methods are also possible, as for example friction welding.
These and additional features of preferred embodiments of the invention will be found not only in the claims but also in the description and the drawings, and the individual features can each be realized by itself or together in the form of subcombinations in the embodiment of the invention and in other fields, and can constitute advantageous as well as independently patentable embodiments, for which protection is hereby claimed.
REFERENCES:
patent: 2869670 (1959-01-01), Hoffman
Evenson, McKeown, Edwards & Lenahan P.L.L.C.
Filterwerk Mann & Hummel GmbH
Kamen Noah P.
LandOfFree
Induction system, especially for use as an induction port of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Induction system, especially for use as an induction port of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Induction system, especially for use as an induction port of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2442513