JPH0452418Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is used in the technical field of engine exhaust systems, and particularly relates to a catalytic converter mounting structure in a dual exhaust system.

(Prior art) In general, engine exhaust systems include a single exhaust system that exhausts air through a single exhaust pipe, and a V-type engine, etc., has a single exhaust system that exhausts air through a single exhaust pipe, and a V-type engine, etc., has a single exhaust system that exhausts air through a single exhaust pipe. There is a dual exhaust system (see Japanese Patent Publication No. 10052/1983) that exhausts air through two exhaust pipes. In any of the exhaust systems, a catalytic converter is interposed in the middle of an exhaust pipe that is connected to the exhaust manifold of the engine for the purpose of purifying exhaust gas. In addition, a thermosensor is attached to the catalytic converter to constantly detect the temperature of the catalytic converter in case the temperature becomes abnormally high due to a failure or the like. and,
The mounting position of the thermosensor in a conventional dual exhaust system is to use a catalytic converter a with the same configuration on the left and right sides as shown in Figure 4a, and to lead the wiring c of the thermosensor b to the left and right sides separately to the vehicle body. As shown in Fig. 4b, the thermosensor b uses two types of symmetrical catalytic converters a and a.
One that leads all the wiring c to the car body side (1985)
-Refer to Publication No. 6498).

(Problem to be solved by the invention) However, in the structure shown in Fig. 4a, the wiring c of the thermosensor b is guided separately to the wiring mounting position on the left and right sides of the car body, so that it is difficult to lock the wiring c to the car body. There is a problem that the number of parts such as locking tools increases. Further, in the structure shown in FIG. 4B, the left and right catalytic converters are not shared, and therefore the left and right catalytic converters require separate manufacturing processes, which poses problems in terms of workability and manufacturing cost.

In view of this, the present invention aims to achieve both the common use of both catalytic converters and the unification of thermosensor wiring in a dual exhaust system.

(Means for solving the problem) In order to achieve the above object, the solution of the present invention is an exhaust system of an engine in which a catalytic converter having a thermosensor is installed in two exhaust pipes arranged in parallel. In the above, both of the catalytic converters have the same configuration, and are arranged in each exhaust pipe so that the mounting positions of the thermosensors face each other so that the phases are different from each other by 180° around the axis of the exhaust pipe. It is assumed that the wiring for the thermosensor in each catalytic converter is bundled between both catalytic converters and then led to the wiring mounting position on the vehicle body.

(Function) With the above configuration, in the present invention, both the catalytic converters can be shared, and the wiring of the thermosensor attached to the catalytic converter can be attached to the vehicle body all at once.

(Example) Next, Figures 1 to 3 show examples of the present invention.
This will be explained along the diagram.

In an engine 1 (such as a V-type engine) having a dual exhaust system as shown in FIG. 3
Catalytic converters 4 connected by a and 3b are interposed and form a pair on the left and right.

A thermosensor 5 for detecting the temperature of the catalytic converter 4 is attached to the rear (exhaust port side) of the catalytic converter 4. The reason why the thermosensor 5 is attached to the rear part of the catalytic converter 4 is that the rear part of the catalytic converter 4 is hotter than the front part due to a chemical reaction taking place inside, and the purpose is to detect that high temperature part. It is. The thermosensor 5 is attached to the catalytic converter 4 by screwing the threaded portion 5a of the thermosensor 5 into a nut 4b welded to the outer wall 4a of the catalytic converter 4, as shown in FIG. Temperature sensing part 5
This is done by penetrating the outer wall 4a of the catalytic converter 4 and inserting it into the interior thereof. .

On the other hand, the mounting position of the thermosensor 5 is the second one.
As shown in the figure, they are located inside the left and right catalytic converters 4, 4, facing each other, and are located symmetrically with respect to a point P on the center line l between the two catalytic converters. In other words, both the catalytic converters 4, 4 are
They have the same configuration, and are arranged in each exhaust pipe 2 so that the mounting positions of the thermosensors 5 face each other and are 180° different in phase from each other around the exhaust pipe axis. This is the catalytic converter 4 on one side.
can be used as the other catalytic converter 4 by rotating it 180 degrees, i.e. one type of catalytic converter 4
It has a common configuration that can be applied to both the left and right sides.
The wiring 5c of the thermosensor 5 extends inward of the catalytic converter 4 and is bundled together at a substantially intermediate position between the two catalytic converters 4, 4, and then guided to the wiring installation position on the vehicle body, and attached to the vehicle body with a locking tool. (not shown).

(Effects of the invention) As described above, according to the invention, the left and right catalytic converters are common, so there is no need to provide two types separately for the left and right, which is superior in terms of workability and manufacturing cost. By guiding the sensor wiring all together to the mounting position on the vehicle body, it is possible to reduce the number of parts such as a fixture for securing the wiring to the vehicle body, and this has the effect of simplifying the securing work.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention, Figure 1 is a plan view of an engine with a dual exhaust system, and Figure 2 is a diagram showing the mounting position of the thermosensor as seen from the arrow in Figure 1. , FIG. 3 is an enlarged cross-sectional view of the part where the thermosensor is attached to the catalytic converter. FIG. 4 is a diagram showing the mounting position of a conventional thermosensor. 1...Engine, 2...Exhaust pipe, 4...Catalytic converter, 5...Thermo sensor, 5c...Wiring.

Claims (1)

[Scope of Claim for Utility Model Registration] In an engine exhaust system in which catalytic converters each having a thermosensor are interposed in two exhaust pipes installed in parallel, both catalytic converters have the same configuration,
The thermosensors are arranged in each exhaust pipe so that the mounting positions of the thermosensors face each other and the phases differ by 180° around the axis of the exhaust pipe, and the wiring of the thermosensors in each catalytic converter is An engine exhaust system structure characterized in that the exhaust system is connected between the two and then guided to the wiring installation position on the vehicle body.