JP2600762Y2 - Exhaust pipe routing structure for automobiles - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust pipe routing structure for an automobile.

[0002]

2. Description of the Related Art In an automobile, the exhaust of an engine mounted in a front part in an engine room passes under the engine, straddles the upper side of a rear steering gear box, and extends along a lower side of a floor panel behind the rear side. In general, the exhaust pipe is provided to the rear of the vehicle body, and is discharged from the rear of the vehicle body through a muffler to the rear of the vehicle (see, for example, Japanese Utility Model Laid-Open No. 3-73612).

For example, in a front-wheel-drive vehicle with a horizontally opposed engine, as shown in FIG. A single exhaust pipe a merges in front of the cylinder head on the bank side, and the exhaust pipe a is routed rearward under the cylinder head on the left bank side, and a steering gear box b and a front axle shaft are provided at the rear of the engine. A configuration is adopted in which the pipe is routed to the rear, largely bypassing the area above c. In FIG. 2, d is a catalyst device for purifying exhaust gas.

[0004]

As shown in FIG. 2, the conventional construction in which the exhaust pipe a is largely bypassed above the steering gear box b and the front axle shaft c and is piped rearward is a detour part. The bending radius of the exhaust pipe a is easy because of its large radius of curvature, but the space occupied by the arrangement of the exhaust pipe in a narrow engine room becomes large, which hinders the installation of accessories and deteriorates maintainability. In addition, since the exhaust pipe a is located near the joint boot c 'of the front axle shaft c, there is a problem that heat damage countermeasures for the joint boot c' must be specially considered. doing.

An object of the present invention is to address the above-mentioned conventional problems.

[0006]

According to the present invention, an exhaust pipe is provided below an engine, and in an automobile driven by at least a front wheel, the engine passes through a lower side of a cylinder block of one of right and left banks of the engine and is located near a lower rear portion of the engine. An exhaust pipe routed rearward through the lower side of the front differential provided at the front end rises upward between the front differential and a steering gear box behind the front differential and straddles the steering gear box. The structure is characterized in that it is structured to be lowered downward at the rear, and to be piped rearward along the lower side of the vehicle body floor panel.

[0007]

As described above, the conventional exhaust pipe routed across both the steering gear box and the front axle shaft by employing the structure in which the exhaust pipe is routed across only the steering gear box as described above. Compared with the routing structure, the space occupied by the exhaust pipe in the engine room is considerably smaller, and the conventional problems of the exhaust pipe obstructing the installation of accessories and deteriorating maintainability are solved, and Since the exhaust pipe passes under the front differential that is separated from the joint boots of the front axle shaft, there is no risk of the joint boots being damaged by heat, and no measures against heat damage are required.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes a power unit including an engine (horizontally opposed engine) 2, a clutch 3, and a transmission (including a center differential 4 ').
The front differential 5 is disposed at a lower front part of the clutch 3 (rear part of the engine), and left and right output axles of the front differential 5 are connected to left and right front axle shafts 6 and 6 via constant velocity joints 7 and 7. The left and right front wheels 8 are driven.

The left and right exhaust pipes 9a, 9a protruding from the left and right banks of the engine 2 join one exhaust pipe 9 at the lower front part of the engine 1, and the exhaust pipe 9 is connected to one of the left and right banks.
For example, it is routed rearward through the lower portion of the cylinder block on the left bank side, passes under the front differential 5, rises upward between the front differential 5 and the steering gear box 10 behind the front differential 5, and It is straddled over the upper side of the gear box 10, descends downward behind the gear box 10, and is pulled backward substantially along the lower portion of the vehicle body floor panel (not shown). 9 'is a catalyst device for purifying exhaust gas,
Reference numeral 11 denotes a cross member for engine mounting.

As described above, the exhaust pipe 9 rises by utilizing the dead space between the front differential 5 and the steering gear box 10 so that the exhaust pipe 9 straddles only the steering gear box 10. As a result, compared with the conventional configuration in which the exhaust pipe straddles both the steering gear box and the front axle shaft, less space is required for arranging the exhaust pipe in the engine room, and obstacles for mounting auxiliary equipment The conventional problems such as deterioration of the maintainability are solved, and the exhaust pipe 9 is routed rearward through the lower part near the center of the engine 2 and below the front differential 5, as compared with the conventional case. The exhaust pipe 9 has a front axle shaft 6
At a position far away from the boot 7 'of the constant velocity joint 7, there is no possibility that the boot 7' will be damaged by heat.
No heat damage measures are required.

[0012]

As described above, according to the present invention, the space occupied in the arrangement of the exhaust pipe in a narrow engine room can be reduced with an extremely simple configuration, and the exhaust pipe can be attached to auxiliary equipment. Conventional problems, such as obstruction of the vehicle and deteriorating the maintainability, and eliminates the risk that the joint boot of the front axle shaft will be damaged by the heat of the exhaust pipe. The heat damage countermeasure is completely unnecessary, and can bring a great effect in practical use.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, in which (A) is a side view and (B) is a plan view.

FIG. 2 shows an example of a conventional structure, in which (A) is a side view,
(B) is a plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power unit 2 Engine 3 Clutch 4 Transmission 5 Front differential 6 Front axle shaft 8 Front wheel 9 Exhaust pipe 10 Steering gear box 11 Cross member

Claims (1)

(57) [Scope of request for utility model registration] 1. An automobile in which an exhaust pipe is provided below an engine and at least a front wheel is driven, a front differential disposed near a lower rear portion of the engine passing under a cylinder block of one of right and left banks of the engine. An exhaust pipe routed rearward through the lower side rises upward through the space between the front differential and the steering gear box at the rear thereof, and straddles the steering gear box and lowers downward at the rear thereof, An exhaust pipe routing structure for an automobile, wherein the exhaust pipe is structured so as to extend rearward along a lower side of a vehicle body floor panel.