Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
  • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
  • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
  • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
  • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
  • F01N3/28—Construction of catalytic reactors
  • F01N3/2839—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration
  • F01N3/2853—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration using mats or gaskets between catalyst body and housing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
  • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
  • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
  • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
  • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
  • F01N3/28—Construction of catalytic reactors
  • F01N3/2839—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
  • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
  • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
  • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
  • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
  • F01N3/28—Construction of catalytic reactors
  • F01N3/2839—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration
  • F01N3/2853—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration using mats or gaskets between catalyst body and housing
  • F01N3/2864—Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration using mats or gaskets between catalyst body and housing the mats or gaskets comprising two or more insulation layers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
  • F01N2310/00—Selection of sound absorbing or insulating material
  • F01N2310/02—Mineral wool, e.g. glass wool, rock wool, asbestos or the like
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
  • F01N2350/00—Arrangements for fitting catalyst support or particle filter element in the housing
  • F01N2350/02—Fitting ceramic monoliths in a metallic housing
  • F01N2350/04—Fitting ceramic monoliths in a metallic housing with means compensating thermal expansion

Definitions

• This invention concerns catalytic converters principally for motor vehicles.
• Catalytic converters are used for treatment of exhaust gases from motor vehicle engines to render them substantially harmless before emission to atmosphere. Treatment is by passing the exhaust gases through a chamber enclosing as porous ceramic block whose pores are coated with a suitable catalyst.
• the ceramic block is contained in a chamber formed from two half shells welded together at their edges, the chamber having an inlet and an outlet.
• the block is wrapped in fibrous material in order to insulate it from colder temperatures outside the converter, to provide sound proofing and to cushion the ceramic block against expansion and contraction of the chamber.
• a commonly used fibrous material is that sold under the trade name SAFFIL which is 95% alumina and provided as a low density mat.
• SAFFIL 95% alumina and provided as a low density mat.
• two pads of fibrous material are used, one being laid in the first half shell and the other on top of the converter block when it has been laid on the first pad of fibrous material. This method -is unsatisfactory in a number of respects. Firstly, the pads do not always meet at the ends leaving unprotected areas of catalytic converter block. Secondly, the fibrous material is pre-cut and its weight adjusted to be within tolerance, but the resultant pad thickness can vary considerably even by a factor of two. That variation in thickness presents problems when putting together a catalytic converter. Proposals have been made in U.K. Patent Applications Nos. 2171180A and 2205929A for methods of wrapping ceramic blocks to facilitate fitting of same catalytic converters.
• An object of this invention is to provide a way of installing fibrous material about catalytic converter blocks so that the above-mentioned disadvantages are overcome or at least mitigated.
• fibrous material pads for catalytic converter blocks be provided in a preferably sealed envelope.
• said envelope preferably has its depth reduced in at least localised areas or positions by drawing together of opposing faces of the envelope.
• Said drawing together of said envelope faces may be achieved in a variety of ways.
• plastics tags such as of the type used for affixing labels to clothing and the like may be used, such tags comprising a thin flexible plastics rod with a T-bar at each end. Such tags are usually inserted by a specially designed machine.
• the opposed faces of the envelope may be stitched or tacked together either by hand or preferably by machine.
• Tags or stitches may be provided at discrete locations of the envelope, in an ordered pattern or randomly. Stitching or tacking may be provided in separate lines, possibly crossing over each other, or in one continuous line or indeed in any other desirable or convenient formation, particularly from production considerations. The positioning and spacing of tags or stitches may be dependent on the size of the pad of fibrous material.
• the thickness of an envelope containing fibrous material may be controlled to within a desired range irrespective of the original thickness of the pad of fibrous material contained in the envelope.
• the envelopes for use in the present invention are preferably made of plastics material and may be conveniently sealed by heat sealing along edges of overlapped sheets or of a folded sheet of suitable plastics material.
• the plastics material itself should preferably be sufficiently strong to withstand the insertion of tags or stitches, for example without tearing.
• the plastics material is preferably air permeable so that the pad of fibrous material can be flexed to follow the shape of a catalytic converter half shell and/or block and be compressed by said tags or stitching.
• Non-woven textile material made from plastics fibres, such as polypropylene fibres, may be particularly suitable for producing envelopes for the invention.
• Figure 1 shows a pad of fibrous material in an envelope
• Figure 2 shows a pad of fibrous material in an envelope with a first stitch arrangement
• Figure 3 shows a pad of fibrous material in an envelope with a second stitch arrangement
• Figure 4 shows a pad of fibrous material in an envelope with a third stitch arrangement
• Figure 5 shows, a pad of fibrous material in an envelope with a tag arrangement
• FIG. 6 shows a pad of fibrous material in an envelope with a fourth stitch arrangement.
• a pad of fibrous material typically SAFFIL
• an envelope 10 of non-woven textile material made from polypropylene fibres The envelope is formed by heat sealing together edges of overlaid sheets of the textile material with the pad of SAFFIL therebetween or by heat sealing together edges of a sheet of the textile material folded about a pad of SAFFIL. The heat sealed join is indicated at 12.
• enveloped pads will be used in a catalytic converter either side of a catalytic converter block for protection and sound proofing.
• the enveloped pad of Figure 1 is shown treated to reduce its thickness, i.e. by drawing together the opposed larger faces of the envelope. That drawing together is achieved by means of stitching 16 through the envelope.
• the stitching 16 is shown as a continuous line.
• the pad of Figure 2 being thinner is easier to install in a catalytic converter and there is less likelihood of edges thereof being trapped between half shell edges to be welded together.
• stitching 116 is in the form of straight lines in a crossover arrangement.
• stitching 216 is in the form of discrete parallel lines.
• tags 316 of the type comprising a rod and T-bar ends are used to draw the envelope faces towards each other to compress the pad of fibrous material therein.
• the tags 316 are inserted using a special machine and are arranged in an orderly pattern.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Exhaust Gas After Treatment (AREA)
• Catalysts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10676648

Family Applications (1)

Country Status (5)

Families Citing this family (5)

Family Cites Families (5)

• 1990
  • 1990-05-26 GB GB909011858A patent/GB9011858D0/en active Pending
• 1991
  • 1991-05-16 JP JP3509749A patent/JPH05509372A/ja active Pending
  • 1991-05-16 EP EP91909918A patent/EP0531367A1/de not_active Withdrawn
  • 1991-05-16 WO PCT/GB1991/000773 patent/WO1991019082A1/en not_active Ceased
  • 1991-05-27 ZA ZA913990A patent/ZA913990B/xx unknown

Non-Patent Citations (1)

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