JPH0221539Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an apparatus for purifying particulate particulate contained in exhaust gas of a diesel engine.

Conventional technology As a diesel particulate filter purification device,
It is known to place a particulate collection material in the middle of the exhaust pipe. This particulate collection material is made of a filter having three-dimensional pores, such as foamed ceramic, and particulate is collected by such a collection material. As the collection material gets clogged over time, it is necessary to regenerate it. For this purpose, it is known that a heater device is placed facing the collection material to burn the collected combustible particulate. It is being

The applicant of this application previously filed Utility Application No. 58-65012 and Utility Application No.
The structure of such a heater device was proposed in No. 58-171896.

Problems to be Solved by the Invention In the heater device as described above, the heater wire is supported while being folded between two adjacent support insulators arranged radially. For this reason, the length of the heater wire between the folds becomes longer toward the outer periphery, and the amount of expansion due to heat generation during energization increases. On the other hand, since the support insulator is disposed across the exhaust passage, its width is set to a uniform minimum so that the effective cross-sectional area of the exhaust passage can be increased. Therefore, when used for a long period of time, the heater wire undergoes repeated thermal expansion and contraction, and the portions near the outer periphery of the heater wire in the radial direction are subject to greater strain, causing problems such as the wire coming off the supporting insulator or coming into contact with neighboring heater wires. It was hot.

Means for Solving the Problems In order to solve the above problems, the present invention includes a heater device disposed in the middle of the exhaust pipe facing the particulate collection material, and the heater device comprises a plurality of radially arranged heater devices. each support insulator and a heater wire supported while being folded between adjacent support insulators,
A diesel particulate purifying device characterized in that the heater wire support portion of the support insulator is formed by a narrow inner portion and a wide outer portion, increasing the supporting area of the heater wire at the outer peripheral portion. It provides:

Embodiment FIG. 2 shows a schematic configuration of a diesel particulate filter purification device, in which a particulate collecting material 2 is installed in the middle of an exhaust pipe 1 of a diesel engine.
and the heater device 3 are arranged facing each other. Arrow A indicates the flow direction of exhaust gas.

FIG. 3 is a front view of the heater device 3 shown in FIG. 2 as viewed from the collection material 2 side, and a heat-resistant metal support frame 5 is installed inside the outer tube case 4. FIG. As also shown in FIG. 1, the support frame 5 consists of an outer annular portion and six bridging spoke portions extending radially in the center.
Both edges 6 of the spoke portions are bent upward from the base, and a lower support insulator 7 (FIG. 1) is placed in each spoke portion so as to be held between the edges 6.

The supporting surface of the lower support insulator 7 is formed with a U-shaped groove 8 as shown in FIG. 4, and the open end of the groove 8 is formed with a protrusion 9.
As shown in FIG. 3 and FIG. 3, the heater wire 10 can be supported by the adjacent support insulator 7 while being folded back, and the folded portion of the heater wire 10 is accommodated in the groove 8, and the protrusion 9 acts as a retainer. do. With the heater wire 10 supported by the lower support insulator 7 in this manner, the upper support insulator 11 shown in FIG.
is attached, and the upper support insulator 11 and the lower support insulator 7 have holes 12 (fourth
It is fixed to the support frame 5 by welding or the like using a U-shaped heat-resistant pin 13 passing through the hole shown in FIG.

FIG. 3 shows six support insulators 11, 7 and six heater wires 10, and each heater wire 10 is independently supported between adjacent support insulators 11, 7. The outer end of each heater wire 10 is connected to a guide rail 14.
etc., each anode terminal 16 of the connector 15
The inner end of each heater wire 10 is connected to the central common cathode terminal 17 to control the energization to each anode terminal 16 in the connector 15.
Each heater wire 10 can be made to generate heat independently. The number of support insulators 11, 7 and the corresponding heater wires 10 arranged radially is not limited to the above example. Further, the heater wire 10 can be bent near the support insulators 7 and 11 so as to be flush with the surface of the upper support insulator 11, and therefore the heater wire 10 can be brought closer to the collecting material 2. can.

Looking at FIG. 3, it can be seen that the length extending in the circumferential direction between the folded support points of the heater wire 10 (although it is actually linear) becomes longer toward the outer periphery. Therefore, the distortion of the heater wire 10 due to thermal expansion and contraction increases toward the outermost periphery. The present invention prevents the heater wire 10 from coming off from the support insulators 7 and 11 by increasing the supporting area of the outer peripheral portion of the heater wire 10 where the momentum is large.

1 and 4 to 6, the base surface 18 of the lower support insulator 7 has a uniform width, and the upper support surface provided with the groove 8 has a base surface 18 as shown in FIG. An outer support surface portion 19 that rises with the same width as the surface 18 and an inner support surface portion 20 that rises narrowly from the base surface 18 in a crank shape as shown in FIG. 5 are connected. It is completed. The outer support surface portion 20 includes two outer support grooves 8;
These two support grooves 8 form the inner support surface portion 19.
The heater wire 10 can be supported over a larger area or over a longer distance than the support groove 8 of the heater wire 10, that is, the engagement area between the heater wire 10 and the support insulator 7 can be increased. It is possible to correct twisting and the like and prevent the heater wire 10 from coming off. The heater wire 10 is designed to be able to slide within each groove 8.
When the heater wire 10 is extended when energized, the folded part forms the groove 8.
By entering the heater wire deeply, the elongation caused by heat is absorbed, and the central portion of the heater wire 10 is prevented from bending and coming into contact with the collection material 2.

The upper support insulator 11 has a shape corresponding to the upper support surface of the lower support insulator 7. The raised edges 6 of the spoke portions of the support body 5 are folded into claws 6a (FIG. 5) at the step portion formed in a crank shape between the inner support surface 20 and the base surface 18 of the lower support insulator 7. The lower support insulator 7 is bent and caulked to the support frame 5. Furthermore, the lower support insulator 7 has a protrusion 21 (FIG. 4) on the lower half of its inner end, and is pressed against the lower half of the cathode terminal (FIG. 1) having a hexagonal head. Helps with positioning.

FIG. 7 shows a modification of FIG. 6, in which the outer support surface 1
9a is made wider than the base surface 18, and in this case also the inner part is the fifth
It can be similar to that shown in the figure. Figures 8 and 9 show the upper insulator 11 and the lower insulator 7.
In order to fix the
3 shows an example in which plate 23 is used instead of plate 23. The plate 23 covers the upper support insulator 11, and its inner end is welded to the cathode terminal 17, and its outer end is welded to the support frame 5. In this example as well, the heater wire support portions of the upper support insulator 11 and the lower support insulator 7 are wide on the outside and narrow on the inside together with the plate 23.

Effects of the Invention As explained above, according to the present invention, the outer peripheral portion of the heater wire with large strain can be transferred to the support insulator without substantially increasing the cross-sectional area of the heater wire support insulator disposed across the exhaust passage. It is possible to obtain a diesel particulate purifying device that can be held reliably and has excellent durability.

[Brief explanation of the drawing]

Fig. 1 is a partially enlarged perspective view of Fig. 3, Fig. 2 is a schematic diagram showing the outline of the diesel particulate purifying device, Fig. 3 is a detailed front view of the heater device shown in Fig. 2, and Fig. 4 is a partial enlarged perspective view of Fig. 1. Fig. 5 is a sectional view taken along the line - in Fig. 4, Fig. 6 is a sectional view taken through the line - in Fig. 4, and Fig. 7 shows a variation of Fig. 6. 8 is a perspective view of another embodiment, and FIG. 9 is a sectional view taken along the line - in FIG. 8. 2... Collection material, 3... Heater device, 7, 11...
... Support insulator, 10 ... Heater wire, 19 ... Outer support surface, 20 ... Inner support surface.

Claims (1)

[Scope of utility model registration request] A heater device is disposed in the middle of the exhaust pipe facing the particulate collection material, and the heater device includes a plurality of radially arranged support insulators and a heater wire supported while being folded between adjacent support insulators. The diesel particulate is characterized in that the heater wire support portion of the support insulator is formed by a narrow inner portion and a wide outer portion, increasing the support area of the heater wire at the outer peripheral portion. Purification device.