Abstract: An object is to provide a particulate trap for a diesel engine which can efficiently burn particulates trapped by a filter while supplying oxygen by natural convection so that the filter can be regenerated in a short time while minimizing the power consumed by the heater. To accomplish this purpose, end plates 6, 7 and brackets 9 may be welded to compressed portions 4a, 5a of an inner cylinder 4 and an outer cylinder 5; heater-supporting ceramic insulators are mounted, spaced from each other, on a heater 14; and/or an ambient air introducing passage 36 is provided to extend from outside the case into a multiple-cylinder filter provided in the case.

Abstract: A particulate trap which can be used in a medium- or small-sized diesel engine car includes concentrically arranged cylindrical filters made of a three-dimensionally reticulated metallic porous material and a plate-shaped electric heater for regeneration having an output of 400 W or less, and is provided between the filters and spaced therefrom. The filters have a relatively shortened length. The heating amount of the filters by the heater is 0.60 W/cm.sup.2 or more. The filter has an increased thickness to make up for reduction in the filter surface area due to the shortened filter length. With this arrangement, it is possible to achieve a high regeneration efficiency with a low-output heater while suppressing heat loss.