JPS5925856B2 - Honeycomb catalyst cassette forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a honeycomb catalyst cassette for purifying vehicle exhaust gas.

Is there a known honeycomb catalyst cassette for exhaust gas purification as shown in Japanese Utility Model Publication No. 52-36093?This is assembled by pressing upper and lower half-cylindrical outer cylinders in the vertical direction.
Since the elastic support body is shaped like a ridge, the elastic support body receives pressing force only in the vertical direction, so it receives uneven force over the entire circumference, and the density of the elastic support body becomes uneven, resulting in a honeycomb contact. This has the disadvantage that the support of the medium becomes uncertain and the honeycomb catalyst body rotates and is damaged by wear.Also, since the lower ends of the upper and lower outer cylinders must be overlapped and pressed, a gap is created in the overlapping part and the sealing performance is poor. Unfortunately, the upper and lower outer cylinders must be fixed by welding in the axial direction, which makes workability poor, and the complex outer shape and uneven protrusions cause a lot of distortion, which is further exacerbated by the thermal cycle of the exhaust gas. It had the disadvantage that it was easily damaged and therefore could not be put into practical use. The present invention aims to eliminate these drawbacks and the method of the present invention will now be described in detail with reference to the accompanying drawings.

1 in Fig. 1 is a cylindrical wire mesh made by knitting heat-resistant thin metal wires, which is corrugated, wrapped in a bag or spirally, and pressed in a mold, with a radial portion 2a and an axial portion as shown in Fig. 2. 2
b are integrated with each other to form an elastic support 2 having an L-shaped cross section. In this case, the density of the elastic support is approximately 0.2 to 1.5 g/d. 3 is a heat-resistant sealing member, which is made by wrapping asbestos, glass wool, carbon fiber, steel wool, etc. as a non-woven band around the outer circumference of a stockinette-knitted cylindrical wire mesh, or by making it into granular powder and attaching it to the cylindrical wire mesh; The cylindrical wire mesh is wrapped into a bag and compressed into a ring shape, which is then cut into a band, or the stockinette knitted cylindrical wire mesh is pressed flat and rolled into a calendar roll using the nonwoven fabric band as a core. , asbestos, glass wool, carbon fiber, and steel wool are made into fibers and knitted together with fine metal wire, and then formed into bags or calendar rolls.

This sealing member 3 is wound around the middle part of the outer peripheral surface of the honeycomb catalyst body 4, and the elastic supports 2 are covered at both corners of the outer surface, and the honeycomb catalyst body 4 is inserted into a heat-resistant case 5 as shown in FIG. At this time, a gap is provided between the radial outer diameter of the elastic support 2 placed over the honeycomb catalyst body 4 and the outer diameter of the seal member 3. Next, the case 5 is compressed while being pressed in the radial direction from both ends toward the center, and both ends of the sealing member 3 are also pressed to press the sealing member into tight contact between the inner surface of the case 5 and the catalyst body 4, and the case 5 is compressed. Both ends of the elastic support 2 are further bent in the radial direction to form a flange 5a, and the density of the elastic support 2 is 0.2 to 3.01.
/d to form a honeycomb catalyst force set as shown in FIG. 4. End 5a' of flange 5a
can be strongly squeezed by further bending it inward in the axial direction as shown in FIG. Next, the usage conditions of the honeycomb catalyst body set formed by the method of the present invention will be explained.

As shown in FIG. 6, the end 7a of the muffler 7 and the end 8a of the exhaust pipe 8 are fitted and fixed to both ends of the case 5 of the honeycomb catalyst set 6 by welding. Note that the outer shape of the honeycomb catalyst body and the case may be any geometrically well-balanced shape such as an ellipse, a quadrangle, a hexagon, etc. other than a circle.

According to the present invention, since the outer circumference of the case is uniformly pressed to compress the elastic support body and the sealing member, the density can be made uniform over the entire circumference, and the honeycomb catalyst body can be held with a predetermined elasticity. The honeycomb catalyst body will not rotate or be damaged due to vibration, and since a sealing member is tightly pressed between the inner surface of the case of the honeycomb catalyst force set and the outer surface of the honeycomb catalyst body, there is no possibility of passing through this part. Furthermore, since the outer shape of the honeycomb catalyst body set is geometrically well-balanced, it is characterized by extremely little distortion and resistance to damage even during thermal cycles. It is something.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the cylindrical wire mesh used in the present invention, and FIG. 2 is a front sectional view of an elastic support obtained by compression molding the cylindrical wire mesh of FIG. 1.
Figure 3 is a front cross-sectional view of the main part of a honeycomb catalyst body covered with an elastic support and a sealing member before being pressed and inserted into a case;
The figure is a cutaway front view of essential parts of a honeycomb catalyst body set formed by the method of the present invention, FIG. 5 is a front cross-sectional partial view showing another embodiment of the part A in FIG. FIG. 3 is a front view with a main part cut away when the honeycomb catalyst strength set is in use. 2...Elastic support, 3...
・Sealing member, 4 ...Honeycomb catalyst body, 5
・ ・ ・ ・ ・ ・Case, 6...Honeycomb catalyst physical strength set.

Claims (1)

[Claims] 1. Cover the outer corner of the honeycomb catalyst body with an elastic support made of thin metal wire in the radial and axial directions, wrap a sealing member around the middle part of the outer surface, and attach both ends of the case covered with the outer surface in the axial and radial directions. A method for forming a honeycomb catalyst cassette in which an elastic support is compressed to a predetermined density by pressing, and a sealing member is pressed onto an inner surface of the case and an outer surface of the honeycomb catalyst by pressing the middle part of the outer surface of the case.