Wall-Flow Diesel Particulate Filters—Their Pressure Drop and Collection Efficiency

A particulate trap for diesel engine use which is less likely to vibrate or deform under exhaust pressures achieves goods results in particulate trapping properties, pressure drop, durability and regenerating properties. This trap has a filter element having a plurality of flat or cylindrical filters of three-dimensionally reticulated porous member. Longitudinally extending exhaust incoming and outgoing spaces are defined alternately between the adjacent filters by alternately closing the inlet and outlet ends of the spaces between the adjacent filters. Gas permeable reinforcing members are inserted in the exhaust outgoing spaces to prevent the filter from being deformed due to the difference between the pressure upstream and downstream of each filter produced when exhausts pass through the filters. Similar gas permeable reinforcing members may also be inserted in the exhaust incoming spaces or at both ends of the filter element to more positively prevent vibration of the filters.

Particulate trap for diesel engine

A filter device inserts into a duct having flow passing from upstream to downstream. The filter device includes fluted filter media having flutes (24) formed therein. The filter forms a seal between the outer edge of the filter and the downstream side of the duct. The filter media may be rolled or stacked in layers to match the shape of the duct.

Inline filter apparatus

An exhaust gas purification device having a NOx absorbent includes a by-pass passage for by-passing the NOx absorbent, an exhaust gas flow rate control portion for regulating both a flow rate of exhaust gas flowing to the NOx absorbent and the flow rate of the exhaust gas bypassing the NOx absorbent, and a reductant addition portion for adding reductant into an exhaust passage upstream of the NOx absorbent In this device, when it is necessary to discharge sulfur components from the NOx absorbent, a temperature rise control is executed such that a temperature of the NOx absorbent becomes higher than a predetermined temperature Next, a rich condition control is executed such that an air-fuel ratio of the exhaust gas flowing to the NOx absorbent becomes one of a substantially stoichiometric condition and a rich condition The flow rate of the exhaust gas to the NOx absorbent during the temperature rise control is controlled so as to be higher than that during the rich condition control

exhaust gas purification device

A ball screw device provided with a screw shaft having on the outer peripheral surface thereof a spiral ball rolling groove, a nut assembly having a load region composed of a spiral load rolling groove facing the ball rolling groove of the screw shaft and a non-load region connecting for communication start and terminal ends of the load region with each other to define an endless track for balls, and a ball connecting body formed of a multiplicity of balls rolling on the endless track of the nut assembly and a connecting body for rotatably holding the balls in an aligned state, wherein a guide groove is formed in the endless track of balls for guiding the connecting body of the ball connecting body to the non-load region so that the respective balls move the connecting body in the load region and the connecting body guides and moves the respective balls in the non-load region of the endless track, and leading portions are formed at least both end portions of the non-load region near the load region for guiding the connecting body along a direction in which the balls moving in the load region advance. Transfer of the balls between the load region and the non-load region in the endless track is made smoothly to achieve smooth circulation of the balls.

Ball screw device

An exhaust gas filter for diesel particulates, comprising a row of a plurality of channels of honeycomb structure of porous sintered ceramic fiber composite sheet, the ceramic fiber composite sheet being produced by a paper-forming method from a slurry of alumino-silicate fiber and fire clay. The honeycomb structure of the ceramic fiber composite sheet is formed by stacking plane sheets and corrugated sheets one atop the other. The filter exhibits low pressure drop yet highly efficient operation by having a bulk density of the ceramic fiber composite sheet in the range of 0.1 g/cm3 to 0.8 g/cm3.

Exhaust gas filter

This exhaust filter element has a corrugated honeycomb structure made of the porous fibrous ceramics, of which cells are alternately plugged; and is made of material having a higher dielectric factor at an inflow side or an outer circumference portion than at an inside portion. The filter element can be regenerated by irradiation of micro wave after it is soiled by particulates in an exhausted gas.

Exhaust filter element and exhaust gas-treating apparatus

An exhaust gas filter for a diesel engine made by winding a composite sheet formed of a corrugated sheet and a flat sheet, the filter being provided with many narrow openings at the entrance or at the entrance and exit of the filter, wherein the area of the upstream side face is increased to deposit carbon soot on this face and on the entrance exhaust gas channels uniformly. By providing many grooves on the cell walls at the upstream direction, more carbon soot deposits in these grooves. Accordingly, the constitution permits reliable carbon soot ignition, complete carbon soot burn out with smaller quantities of carbon deposition as a whole.

Exhaust gas filter for diesel engine

An exhaust gas filtering element is provided for filtering diesel particulates. The system comprises two filter elements disposed parallel to each other, a burner mechanism, and a four-way valve mechanism for switching over an exhaust gas flow and a preheated gas flow obtained by combustion in the burner mechanism. The exhaust gas flow is generally passed uniformly through the two filter elements which filter off particulates. However, when regeneration is required, an ellipitical vane, provided in a cylinder of the four-way valve mechanism, is rotated so as to cut off the exhaust gas flow passing through one of the filter elements and cause the preheated gas to flow through this filter, whereby particulates are oxidized and incinerated. At this time, the exhaust gas flow is passed through the other filter element, without any particulates being emitted into the atmosphere. Then, the exhaust gas flow and the preheated gas flow are switched by rotating the vane so that the other filter element is regenerated.

Purifier of diesel particulates in exhaust gas

This invention relates to a ceramic burner plate using a fiber composite ceramic (1) of low thermal conductivity having gas passages (3), and provides a burner plate, wherein the burner plate contains a lithium component and such components as nickel, manganese, cobalt, titanium, copper, iron, chromium, and vanadium, to assist in the combustion of gas, and has a surface construction (2) having triangular projections, hexagonal projections or rhombic projections, to ensure increased heat radiation.

Takao Kusuda

Papers

Exhaust gas filter

Exhaust filter element and exhaust gas-treating apparatus

Exhaust gas filter for diesel engine

Purifier of diesel particulates in exhaust gas

Ceramic burner plate