JPH0122894Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to a device (so-called trap) for collecting and removing particulates in the exhaust gas of a diesel engine.

BACKGROUND OF THE INVENTION In a typical device for collecting and removing particulates from exhaust gas in a diesel engine, a filter member and a heater are provided in the case and in close proximity to the filter member. By energizing the heater every time the engine travels a predetermined distance while the engine is running, the particulates collected by the filter material are burned and regenerated, thereby maintaining a state in which particulates can be collected at all times.

When a ceramic heater is adopted as the heater, the heater is divided into a plurality of ceramic elements, and each element is held in the case via its own heat-resistant spring material at the outer periphery, and each element is held at the inner periphery by They are fixed together by bolts via washers to the stay located in the center of the case. In this case, thermal expansion and vibration during assembly or use may cause misalignment of each element, resulting in a problem where the elements interfere with each other.

Purpose and Structure of the Invention The present invention was devised in view of the drawbacks of the prior art, and it is an object of the present invention to provide a structure in which interference between heater elements does not occur despite thermal expansion or vibration.

In the device of the present invention, a ceramic heater is arranged close to a filter material in a cylindrical case and perpendicular to the flow direction of exhaust gas, and the ceramic heater is composed of a plurality of elements distributed in an angular direction. are held by heat-resistant elastic holders at their outer ends, a stay is provided in the center of the case, and all elements are fixed at their inner ends by screws between the stay and the washer. A spacer is fitted onto the screw between them, and the spacer has engaging portions at equal intervals on its inner periphery to engage with the inner ends of each element.

Embodiment Hereinafter, an embodiment will be described with reference to the drawings. In FIG.
is fixed to the intake manifold 11 of the internal combustion engine, and the flange portion 102 at the lower end is fixed to an exhaust pipe (not shown) of the internal combustion engine. A cylindrical filter material 12 made of porous ceramic or the like is arranged inside the case 10. A sealing material 1 made of a heat-resistant material is provided between the outer periphery of the filter material 12 and the inner periphery of the case 10.
4 and 14' are arranged to sandwich the cushion material 16. The lower end of the filter material 12 is connected to the case 1 by a cushion material 18 and a retainer 20.
0 shoulder 103. A heater assembly 22 is disposed on the upper surface of the filter material 12 in close proximity thereto and perpendicular to the flow of exhaust gas. As shown in FIG. 3, the heater assembly 22 consists of six angularly divided elements 24, each of which is fan-shaped as a whole and has a window 240 to allow free flow of exhaust gas. It is said that Each element 24
has a cross section U at its outer circumference 241 (Fig. 1)
A holder 26 made of a letter-shaped electrically conductive elastic body
It is held with a clip. The holder is held between upper and lower holding plates 28 and 30 made of an insulator. A threaded portion 32 extends from the holder 26,
Its threaded portion 32 protrudes through an insulating sleeve 34 inserted into the wall of the exhaust manifold, and the nut 3
6 is concluded. Lead wire 38 to threaded part 32
is connected to the positive terminal of the battery.

In FIG. 1, a plurality of tensioners 40 extend radially from the inner wall of the exhaust manifold 11, and a stay 42 extends downward from the center.
The inner end 242 of the heater element 24 is attached to the inner end 242 of the heater element 24 . That is, the inner end 242 (FIG. 2) of each element 24 extends to this stay 42 and is fixed by a bolt 48 via a washer 46. This fixed portion also serves as a ground terminal for the heater 22.

According to the present invention, a separator 50 is located between the washer 46 and the stay 42 and inserted into the bolt 48. The separator 50 has six recesses 501 as engaging parts formed at equal intervals on its outer periphery, and the rounded inner end 2 of the heater element is formed in the recesses 501.
42 are fitted. Therefore, each heater element 2
4 are reliably held with a predetermined gap S between them, and do not interfere with each other even when subjected to vibration or thermal expansion.

When the present invention is used, the heater 22 is normally not energized. By energizing the heater 22, the particulate matter that has been collected on the filter material 12 is ignited and burned, thereby ensuring the collection function of the filter material at all times.

Effect of the invention Each filter element 24 is placed in the recess 5 of the separator 50.
01, each element can be held at a distance S regardless of vibration or thermal expansion, and problems caused by mutual interference can be solved.

[Brief explanation of the drawing]

Fig. 1 is a side view partially showing the device of the present invention in cross section, Fig. 2 is a partial enlarged view of Fig. 1 showing the attachment part of the inner end of the heater element to the stay, and Fig. 3 is a partially enlarged view of the device of the present invention.
An arrow view seen from the − direction in the figure. 10...Case, 11...Exhaust manifold, 1
2... Filter material, 22... Heater, 24... Heater element, 241... Outer end of heater element, 242...
... Heater element inner end, 26 ... Holder, 42 ... Stay, 46 ... Washer, 48 ... Bolt, 50
. . . Spacer, 501 . . . Recess as an engaging portion.

Claims (1)

[Scope of utility model registration request] Inside the cylindrical case, a ceramic heater is arranged close to the filter material and perpendicular to the flow direction of the exhaust gas, and the ceramic heater is composed of a plurality of elements distributed in the angular direction, and each element is A stay is provided in the center of the case, and all elements are fixed at their inner ends with screws between the stay and the washer, and a spacer is attached to the screw between the washer and the stay. An exhaust gas purification device for an internal combustion engine, in which the spacer is fitted, and the spacer has engaging portions at equal intervals on its inner periphery to engage with the inner ends of the respective elements.