Ported automotive speaker enclosure apparatus and method

The present invention discloses a ported reflex speaker enclosure for use in the automotive audio systems industry. The ported reflex speaker enclosure is a design that factors the audio and thermal design considerations as found in the automotive operating environment as well as factoring the audio and mechanical mounting considerations as found in the automobile audio systems. The ported reflex speaker enclosure is primarily intended for six (6) by nine (9) inch standard speaker chassis used in automotive audio systems that typically are found as non-enclosed suspended speakers in the trunk compartment of automobiles. The speaker enclosure is a concave body having an oval shaped rim portion for receiving a similarly shaped speaker device, a convex bottom, a first sound fidelity enhancement reflex port for directing sound waves to a listening compartment, a second sound fidelity enhancement in the form of an exhaust hole for controlling sound wave pressure emanated from an enclosed speaker located within the concave body and a third sound fidelity enhancement in the form of equalizing notches that complement the exhaust hole's control of sound wave pressure emanated from an enclosed speaker.

FIELD OF THE INVENTION 
The present invention relates to speaker enclosures. More particularly, the 
present invention relates to speaker enclosures for automotive audio 
systems. Even more particularly, the present invention relates to speaker 
enclosures for automotive audio systems of the type that are provided with 
reflex ports for improving the audio frequency response of the audio 
system. 
DESCRIPTION OF THE PRIOR ART 
The prior art has taught that the frequency response, hence sound fidelity, 
of a speaker can be enhanced and be made more efficient by enclosing the 
speaker in some cabinet or enclosure. One method known concerns the 
enhancement of the sound fidelity by using a ported reflex enclosure 
whereby a tube is built into the cabinet that allows a certain amount of 
air to move in and out during operation of the cone member of the speaker. 
These type of speaker enclosure system results in getting a deeper bass 
from the system. The object of this type of enclosure is to place the low 
frequency vibrations in-phase with the operating speaker cone motion to 
achieve the enhanced sound output from the audio system. The amount of air 
displaced within the enclosure can vary according to the operating volume 
of the speaker, thus an efficient ported reflex enclosure must be tuned 
considering the maximum volume of the speaker in relation to the enclosure 
volume. The cross-sectional area and the length of the port must be 
factored along with the enclosure volume in tuning the enclosed speaker. 
Typical of speaker enclosures that relate to the ported reflex enclosures 
are U.S. Pat. No. 4,284,166 that teaches a port device for improving 
bass-reflex speaker systems directed at preventing booming and other 
resonance effects and distortions by utilizing a port to factor acoustical 
compliance of the enclosure considering the mass of the air moving 
inwardly and outwardly from the enclosure. While recognizing sound 
fidelity enhancement resulting from controlling the air pressure within 
the enclosure, the patented structure does not contemplate an automotive 
operating environment and associated sound distribution and cooling 
considerations. Other ported speaker apparatus can be found in the 
teachings of U.S. Pat. Nos. 4,635,748, 4,398,619, 4,785,908, 4,134,471 and 
4,006,311 and are similarly not directed at the automotive operating 
environment. 
As applicant has found, the enclosure of speaker systems has bee widely 
addressed in quest of better sound fidelity and has generally been 
directed at enclosures for home entertainment use, as opposed to the 
automotive industry use. Generally, speaker systems for the automotive 
industry are installed in leftover space in the dash, door panels, side 
panels or are suspended in the rear trunk compartment with appropriate 
cut-out panels beneath the rear window area for directing the sound waves 
from the top of a speaker into the listening compartment. The speakers in 
the automotive industry are typically not enclosed in the traditional 
sense of an enclosure and can be considered, for all intents and purposes, 
a non-enclosed speaker. Because of the non-enclosed nature of the 
automotive speaker systems, the advantages of enhanced sound fidelity, as 
generally available in the home entertainment industry, are not found in 
automotive audio system. While custom audio systems may include means that 
enhance the sound fidelity of the audio systems, there are no known 
commercially available enclosures that can be readily installed by the 
average consumer over non-enclosed speakers in automobiles to achieve 
sound fidelity enhancements such as found in ported reflex enclosure for 
the home audio entertainment industry. 
Therefore, a need is believed to exist for a ported reflex speaker 
enclosure for the automotive industry that takes advantage of the sound 
fidelity enhancements possible utilizing ported reflex enclosure 
techniques that are widely available in the home audio entertainment 
industry. 
SUMMARY OF THE INVENTION 
It is therefore a primary object of this invention to provide a ported 
reflex speaker enclosure for use in the automotive audio systems industry. 
It is another object of the present invention to provide a ported reflex 
speaker enclosure that factors the audio and thermal design considerations 
as found in the automotive operating environment. 
It is yet another object of the present invention to provide a ported 
reflex speaker enclosure that factors the audio and mechanical mounting 
considerations as found in the automobile audio systems. 
It is a particular object of the present invention to provide a ported 
reflex speaker enclosure for six (6) by nine (9) inch speaker chassis used 
in automotive audio systems and typically found as non-enclosed suspended 
speakers in a wide wattage range in the trunk compartment of automobiles. 
The present invention satisfies the foregoing objectives by providing a 
speaker enclosure apparatus designed to enhance an automotive audio system 
speaker's sound fidelity that comprises a concave body having a 
substantially oval shaped rim portion for receiving a similarly shaped 
speaker device, a convex bottom, a first sound fidelity enhancement means 
for directing sound waves to a listening compartment, a second sound 
fidelity enhancement means for controlling sound wave pressure emanated 
from a speaker located within said concave body and a plurality of third 
sound fidelity enhancement means for equalizing sound wave pressure 
emanated from an enclosed speaker. The concave body is designed to produce 
reflex sounds for the enclosed speaker and includes having a first tapered 
side wall integral with the rim portion, a second tapered side wall 
integral with the first tapered sidewall at an end opposed from the rim 
portion and being integral with the convex bottom to form the concave 
body. The interior surface of the concave body is provided with a rough 
surface texture to disperse the sound waves that contribute to the sound 
fidelity improvement of the enclosure. The reflex port is the first sound 
fidelity enhancement means and comprises being shaped having an elongated 
U-shaped notch located on one side of the rim portion. The side having the 
port being oriented during installation to direct sound waves from the 
speaker enclosure apparatus to the listening compartment. If desired, the 
enclosure may be rotated 180 degrees to direct the port in another 
direction. To help tune the speaker enclosure to deliver enhanced sound 
waves, the second sound fidelity enhancement means, in the form of a hole 
is provided at the convex bottom's apex. The interior bottom is convex to 
form a depression on the exterior bottom that better enables drawing air 
from within the trunk compartment to effect convection cooling of the 
speaker. As a fine tuning means for equalizing sound wave pressure within 
the enclosure, the plurality of third sound fidelity enhancement means are 
provided in the form of a plurality of perimeter disposed U-shaped notches 
on the rim portion. The U-shaped notches not only enable sound pressure 
equalization, but, also provide an entry port for electrical wiring 
required for speaker operation. Also, to enable easy attachment of the 
enclosure to a speaker, selected ones of the plurality of perimeter 
disposed U-shaped notches have mounting holes for receiving mating 
mounting hardware, such as an end of a bolt securing a speaker. The 
mounting holes on the U-shaped notches are disposed in a mounting hole 
pattern that is dimensionally larger than a pattern of the mating mounting 
hardware provided on a speaker. The concave body is preferably 
manufactured from a plastic material that will enable the rim portion to 
be flexed during attachment of the enclosure to the speaker to cause a 
momentary alignment of the mounting hole pattern with the speaker's mating 
mounting hardware to effect a compressed securement of said speaker within 
said concave body. 
Therefore, to the accomplishments of the foregoing objects the invention 
consists of the foregoing features hereinafter fully described and 
particularly pointed out in the claims, the accompanying drawings and 
following disclosure describing in detailed the invention, such drawings 
and disclosure illustrating, however, but one of the various ways in which 
the invention may be practiced.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to FIG. 1 where there is shown an automobile V having an 
audio system provided with a speaker 10 that is enclosed with an enclosure 
apparatus 20 having a reflex port 21 according to the present invention. 
The enclosure is preferably shaped to fit an automotive six by nine inch 
standard speaker chassis that can be electrically designed to wide wattage 
ranges and typically differ in the size of the magnet at the bottom of the 
cone member of the speaker. 
FIG. 2 illustrates, by example, a speaker 10 mounted to a panel 12 
typically provided on the rear portion of the passenger compartment 
beneath the rear window, which panel comprises the upper portion of a 
trunk compartment of most automobile. The speaker is typically mounted 
using hardware 11 comprising a bolt and nut arrangement having the bolt 
extending beyond the nut to which an enclosure, such as enclosure 
apparatus 20 according to present invention, can be attached. As best seen 
in FIG. 3 the speaker enclosure apparatus 20 is substantially a concave 
body having a substantially oval shaped rim portion 25 for receiving a 
similarly shaped speaker device, a convex bottom, designated C, a reflex 
port 21, termed a first sound fidelity enhancement means for directing 
reflex sound waves to a listening compartment, a hole 22 located on the 
apex of the convex bottom C, and termed a second sound fidelity 
enhancement means, for controlling and exhausting compressed sound wave 
pressure emanated from speaker 10 located within said concave body and a 
plurality of third sound fidelity enhancement means 23 for equalizing 
sound wave pressure emanated from an enclosed speaker. 
Referring to FIGS. 2, 3 and 4, the concave body is designed to produce 
reflex sounds for the enclosed speaker 10 and includes having a first 
tapered side wall designated T1 integral with the rim portion 25, a second 
tapered side wall designated T2 integral with the first tapered sidewall 
T1 at a end opposed from rim portion 25 and being integral with the convex 
bottom C to form the concave body. The interior surface of the concave 
body is provided with a rough surface texture ST used to disperse the 
sound waves that contribute to the sound fidelity improvement of the 
enclosure. As best seen in FIG. 3, the reflex port 21 comprises being 
shaped having an elongated U-shaped notch located on one side of rim 
portion 25. The side having reflex port 21 generally being oriented during 
installation to direct sound waves from the speaker enclosure apparatus to 
the listening compartment of automobile V. If desired, the enclosure may 
be rotated 180 degrees to direct the port 21 in another direction if the 
deeper base sound are not desired to be directed into the listening 
compartment. As a fine tuning means for equalizing sound wave pressure 
within the enclosure 20, the plurality of third sound fidelity enhancement 
means 23 are provided in the form of a plurality of perimeter disposed 
U-shaped notches on the rim portion 25. The U-shaped notches not only 
enable sound pressure equalization, but, also provide an entry port for 
electrical wiring required for speaker operation (not shown). The tuning 
to produce the enhanced sound from the enclosed speaker is accomplished by 
controlling the size and shape of the first, second and third sound 
fidelity enhancement means. In the preferred embodiment, for a six by nine 
inch speaker, the reflex port 21 is an elongated U-shaped notch measuring 
0.5 inch wide by 3.8 inch long bottom of notch (5.0 inch top of notch) by 
0.6 inch deep, the exhaust hole 22 measuring 0.45 inches in diameter. The 
equalizer U-shaped notches 23 measure 0.33 inch wide by 0.33 inch long 
bottom of notch (0.75 inch long top of notch) by 0.33 inch deep. The 
interior bottom C is convex to form a depression on the exterior bottom 
that better enables drawing air from within the trunk compartment through 
hole 22 to effect convection cooling of the speaker, primarily the 
speaker's magnet M, as shown by arrows A6 in FIG. 6. Also, as shown in 
FIG. 4, to enable easy attachment of the enclosure 20 to speaker 10, 
selected ones of the plurality of perimeter disposed U-shaped notches 23 
have mounting holes 24 for receiving matinq mounting hardware 11, 
typically an extended portion of a mounting bolt. The mounting holes 24 on 
the U-shaped notches 23 are disposed in a mounting hole pattern that is 
dimensionally larger than a pattern of the mating mounting hardware 
provided on a speaker. The concave body is preferably manufactured from a 
plastic material that will enable the rim portion 25 to be flexed, as 
shown by arrow A1, A2, A3 and A4 during attachment of the enclosure to the 
speaker to cause a momentary alignment, shown as hole 24a, of the mounting 
hole pattern with the speaker's mating mounting hardware to effect a 
compressed securement of said speaker within said concave body. In the 
preferred embodiment, the hole pattern dimensioning for holes 24 and 24a 
relate such that dimension D2 is greater than D1 bt 0.045 inches and 
dimension D4 is greater than D3 by 0.045 inches, see FIGS. 2 and 6 for the 
speaker mounting dimensions D1 and D3. 
Referring to FIGS. 2 and 5, an enclosed operating speaker 10 can generate 
sound waves within the enclosure 20 that compresses the air within the 
volume of the enclosure 20. The arrangement produces enhanced sound waves 
A7 at reflex port 21 by controlling the amount of compressed air being 
exhausted out hole 22 as shown by arrow A5. The notches 23 disposed on rim 
25 equalize the exhausted compressed air and complement the amount of 
compressed air being exhausted out hole 22. Collectively, hole 22 and 
notches 23 control the back pressure on the speaker's cone member to 
optimize cone movement to match low frequency vibrations. 
Therefore, while the present invention has been shown and described herein 
in what is believed to be the most practical and preferred embodiments, it 
is recognized that departures can be made therefore within the scope of 
the invention, which is therefore not to be limited to the details 
disclosed therein but is to be accorded the full scope of the claims so as 
to embrace any and all equivalent apparatus.