A unitary combined muffler and air purifier for internal combustion engine exhaust systems having a replaceable canister for charcoal chunks or the like and other replaceable filter components, together with a fan to overcome back pressure in the unit. The device is characterized by simplicity, economy of construction, durability, minimum weight and ease of maintenance.
Application Number:
04/815385
Publication Date:
07/20/1971
Assignee:
Myerly, Richard D. (Hagerstown, MD)
, Cook Gene A. (Hagerstown, MD)
, Hurd James E. (Hagerstown, MD)
, Price William G. (Hagerstown, MD)
, Cale William E. (Hot Springs, VA)
Jr., Cale Virgel M. (Hot Springs, VA)
Other Classes:
55/482, 55/357, 96/380, 60/311, 181/225, 55/DIG.030, 55/323, 60/315, 55/473
International Classes:
F01N3/033; F01N3/08; F01N7/02; F01N7/00; B01D50/00
Field of Search:
55/276ET,267,316,322,323,325,327,331,332,350,467,471,387,472,473,279,463,482 60/29 181/50 230/120
US Patent References:
| 3227241 | Ceramic mufflers | January 1966 | Mattoon | |
| 3406501 | Automobile engine exhaust filter | October 1968 | Watkins | |
Primary Examiner:
Lutter, Frank W.
Assistant Examiner:
Nozick, Bernard
Claims:
I claim
1. An exhaust muffler and purifier unit comprising an exterior cylindrical shell having one open end and having an opposite end wall, an exhaust pipe section of reduced diameter connected centrally in said end wall of the shell and adapted for connection externally of said end wall with an exhaust pipe, a conically flared enlargement connected with said pipe section within the shell near said end wall and extending to the sidewall of the shell and having its forward end secured to the sidewall of the shell substantially forwardly of the shell and wall, an electric motor disposed within the shell centrally near and forwardly of the flared enlargement and having a rotor at its forward end including plural radial impeller blades whose tips extend close to the bore of the shell, radial bracket means supporting the motor and anchoring it to the sidewall of the shell between said blades and enlargement, a rearwardly tapering conical heat shield secured to the bracket means and substantially covering the motor and projecting concentrically into the flared enlargement and spaced therefrom so as to form a flaring annular passage around the motor for exhaust gases, said impeller blades disposed immediately forwardly of the outlet of said annular passage around said motor, an abutment ring in the shell near its longitudinal center forwardly of the impeller blades, a first removable filter pad within the shell at the forward side of the abutment ring, a second filtering and cooling element removably mounted within the shell forwardly of said first filter pad and substantially contacting the latter, a cylindrical canister containing gas-purifying charcoal elements disposed removably in the shell immediately forwardly of said second filtering element and having perforated end walls and extending substantially to the forward open end of the shell, and a tapering forward end cover member detachably secured to the shell and having a forward reduced diameter pipe extension adapted to be coupled with an exhaust tailpipe.
Description:
BACKGROUND OF THE INVENTION
There is a great need at the present time for an effective and economical purifying means for automotive exhaust systems, because of the acute worldwide air pollution control effort. A number of different approaches to solving the problem of air pollution due to automotive exhaust constituents have been offered. Some of these proposals involve improved combustion within the engine and/or improved carburetion. Others involve recycling or reburning of exhaust products before final emission into the atmosphere. Still others broadly similar to this invention propose direct placement in the exhaust conduit of a device for removing at least the more dangerous pollutants. In order for such a device to be successful and practical, it must be economical to manufacture and install without adding greatly to the total cost of the automobile or altering the otherwise conventional parts of the exhaust system, and the device must not adversely effect engine performance. To be successful, the purifier device must also be easy and economical to maintain after installation. Prior art devices of this general character have failed to measure up fully to the above requirements and as yet no completely satisfactory exhaust purifier unit or muffler has been devised.
The present invention is believed to fully satisfy the above needs and requirements of the art through the provision of a simple unit which may take the place of the conventional automobile muffler by coupling into the standard exhaust pipe without any alteration of vehicle structure or performance. The unit has easily replaceable components, is protected against excessive heat and is completely safe and reliable in operation. It is also made of high-grade materials which resist corrosion and other deterioration during a long useful life. Further advantages and features of the invention will appear to those skilled in the art during the course of the following description.
BRIEF DESCRIPTION OF DRAWING FIGURES
FIG. 1 is a central vertical longitudinal section through an exhaust muffler and purifier unit embodying the invention;
FIG. 2 is a transverse vertical section taken on line 2-2 of FIG. 1;
FIG. 3 is a similar section on line 3-3 of FIGURE 1;
FIG. 4 is a further similar section on line 4-4 of FIGURE 1; and
FIG. 5 is a central vertical longitudinal section through a unit embodying a modification.
DETAILED DESCRIPTION
Referring to the drawings in detail, wherein like numerals designate like parts, and referring initially to FIGURES 1 through 4, the numeral 10 designates a muffler body or shell of cylindrical form and constructed of materials which may include copper, zinc or the like which resist corrosion. The upstream end of the shell 10 has an end wall 11 receiving centrally therethrough a pipe section 12 which may be coupled to the usual vehicle exhaust pipe, not shown, leading from the engine. Within the shell 10, the pipe section 12 carries a conically flared head or enlargement 13 having a marginal flange 14 preferably welded to the shell.
A conical heat shield 15 of suitable material is placed axially forwardly of the head 13 and projects partly thereinto and the heat shield is fixed to the surrounding shell 10 through radial brackets 16 preferably welded thereto as well as to the shell 10. Disposed centrally within the heat shield 15 in spaced relation therewith is a fan motor 17 supported by opposing clamp straps 18 whose radial legs 19 are welded to the interior of the heat shield 15, FIGURE 2. The motor armature shaft 20 has secured thereto a disc 21 having a plurality of fan blades 22 formed thereon integrally. The blades 22 lie immediately inside of the shell 10, FIGURE 3, and immediately in front of the annular passage around the heat shield 15. In some cases, the motor 17 may be dispensed with and the fan blades may be operated by exhaust pressure. The lead wires from the electric motor are omitted in the drawings for simplicity but such wires may be covered with suitable insulation and are brought out through the wall of the shell 10 in a conventional manner. As shown in FIGURE 1, the blades 22 are located near the longitudinal center of the shell 10.
Downstream from the motor 17 there is provided a fiber glass filter disc or pad 23 approximately 1 inch in thickness. This filter disc is fibrous and allows the passage of exhaust gases without great resistance while effectively filtering out particles. The filter element 23 is backed up by a fixed ring 24, welded or otherwise secured to the shell 10 of the muffler. Immediately downstream from the filter disc 23 is another disc or filter element 25 formed of asbestos and preferably being about 21/2 inches thick. The element 25 has honeycomb openings formed therethrough axially to allow the free passage of exhaust products without excessive back pressure. An important purpose of the element 25 with its great internal surface area is to dissipate heat and thus protect from heat the downstream charcoal canister or cartridge 26, now to be described.
The canister 26 is mounted removably in the downstream or rear end of the shell 10 and embodies a suitable cylindrical casing 27 having perforated end walls 28, as shown. The canister is filled with charcoal chunks 29 or other similar purifying material and the canister 26 is equipped with a ring 30 at its downstream end to facilitate quick removal from the shell 10 and replacement when spent. The elements 23 and 25 are also easily removable from the shell 10 when the charcoal canister is removed.
The downstream end of the shell 10 has a cap or cover 31 including a short pipe extension 32 to be directly coupled in the exhaust tailpipe in a conventional manner. The cover 31 is releasably secured to the shell 10 by means of clips 33 or other suitable forms of fasteners. The construction renders the unit very easy to maintain and install on the vehicle.
In light of the foregoing description, the use or operation of the muffler and purifier unit should require little if any further explanation. The engine exhaust products enter through the pipe 12 and pass around the heat shield 15 which deflects the products outwardly to the annular passage between the heat shield and the wall of shell 10. The fan blades push the exhaust products through the filter 23 and cooling filter 25 and finally into and through the charcoal purifying canister 26. The purified exhaust finally passes outwardly to the tailpipe, not shown through the extension 32 and at this point the exhaust products are freed substantially of solid particles and poisonous gaseous constituents.
FIG. 5 shows a modification of the invention which is basically the same as the construction in FIG. 1 except for the fact that the motor and fan are placed near the downstream end away from the heat of the exhaust entering the unit at the upstream end. Hence the need for a heat shield is eliminated and the overall construction is rendered somewhat simpler.
In FIG. 5, a first casing section 34 receives through its upstream end a pipe section 35 having a conically flared head 36 within the casing or shell. The head 36 has a marginal flange 37 welded to the shell 34 with a radial shoulder 38 against which the previously described filter elements 23 and 25 and the charcoal canister 26 are stacked.
A second casing or shell section 39 houses the electric motor 40 having a bladed fan 41 facing upstream in opposition to the flow of exhaust gases and serving to suck the gases downstream rather than to push them as in the case of the motor 17. The motor 40 is bracketed to the casing section 39 by suitable brackets 42 and the motor and fan may have conical deflector portions 43 and 44 as shown to assist the gases in flowing around the motor and out through the downstream pipe extension 45 which corresponds in purpose and function to the extension 32. Since the motor 40 is remote from the high-temperature end of the device, no heat shield is required and the motor will run quite cool. The two casing sections 34 and 39 telescopically interfit as at 46 and are detachably secured together as a unit by fasteners 47.
The operation of the device is basically the same as for the unit in FIG. 1 and the favorable results achieved are basically the same. It is believed that the various features and advantages of the invention have now been brought forth and will be clear to those skilled in the art.