JPS59108816A - Secondary air feeder for engine - Google Patents

Abstract

PURPOSE:To prevent deterioration of appearance and to promote compaction by arranging an exhaust system secondary air feeder in a space produced at the crank shaft end position of primary cylinder and the other side cylinder in V- type or horizontally facing engine. CONSTITUTION:An engine mounted on an auto-bicycle is a V-type engine comprising a cylinder section 4a positioned in front of crank shaft and a cylinder section 4b positioned in the rear. Front cylinder section 4a and rear cylinder section 4b are arranged while shifting in axial direction of crank shaft and an exhaust system secondary air feeder 10 is arranged in a space to be produced at the shaft end position of both shafts.

Description

DETAILED DESCRIPTION OF THE INVENTION V) The invention relates to a secondary air supply device that supplies #r air to the exhaust line of an engine, particularly a V-type or horizontal twin-type engine. The air supply port having a reed valve is connected to the exhaust boat or exhaust pipe which is the exhaust system of the engine, and the reed valve is opened and closed by the pulsation of exhaust gas to supply fresh air to the exhaust line. σJHC (hydrocarbons), C0 (-carbon oxide), etc. in the exhaust gas), U (water), C0
2 (carbon dioxide), and has the advantage of being able to purify exhaust gas with simple equipment, but it is not suitable for vehicles such as motorcycles, where there is little installation space and the arrangement of parts greatly affects the exterior appearance. When the secondary air supply device t is installed in an engine, it is necessary to consider the arrangement of the secondary air supply device and the shape of the engine.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a secondary air supply device that does not impair the appearance or sacrifice compactness even when applied to vehicles such as motorcycles. , its characteristics are ■ type or horizontal vs. same type engine shape? It's about being used effectively.

For example, in a V-type engine, one of a pair of cylinders forming a V-shape is offset (displaced) relative to the other in the axial direction of the crankshaft. 1 prostitute)
When viewed from above, a void corresponding to the offset is formed on the sides of both cylinders. The present invention is to dispose a secondary air supply device in the space 70 Hereinafter, the present invention σ] One embodiment t-Drawings t-Explained with reference to FIG. 1 is an embodiment of the present invention. The main parts of a motorcycle to which this is applied are seen from one side on the left.L is the body frame, 2 is the fuel tank, 8 is the radiator, and 4 is the V-type engine.

This V-type engine 4 has two cylinders formed in parallel, a pair of cylinder parts 4a and 4bt, and cylinder parts 4a and 4bt which are arranged in a V-shape with each other.
:A V-type 44-cylinder engine, with the axis of the crankshaft pointing across the width of the vehicle (in the direction perpendicular to the page in Figure 7), giving it a V-shape when viewed from the side of the vehicle? It is attached to a single frame l so that the total width of the engine is
In contrast, the offset fit (shift amount) of the cylinder parts 4a and 4b is placed on the front left side of the vehicle body and the rear right side of the vehicle body, respectively.
A space 5 and a space 6 having widths W'cv corresponding to the width W'cv are formed.

Bank portion 4C formed by the pair of cylinder portions 4as4b
and the bottom of the fuel tank 2. 17
, an air cleaner case 8, a carburetor 0, etc. are arranged, and in the spaces 5 and 6 located on both sides of the vehicle, there are secondary air supply devices 10 and 11 for supplying engine exhaust boats 4diC@F+air, respectively. The carburetor 9 is arranged so that its suction port 9a is communicated with the base portion 8a of the air cleaner case 8. The configuration of the feeding device 10.11 is 11"i
]- Therefore, the secondary air supply bag filO arranged on the left side of the vehicle body will be explained below with reference to Fig. fs1 and Figs. 3 to 1.

The secondary air supply bag v1tO has an air passage chamber 15FElic in which an air intake port 12 communicating with the air cleaner case 8 is formed in the upper part, and an air supply port 14 having a reed valve 18 in the lower part and the rear part, respectively. Cut off the communication between the air intake port 12 and the air supply port 14 a! The air cleaner case 80 base part 8a connects the air cleaner case 80 base part 8a to the front cylinder part 4Bti] through the hose 17 to the exhaust port 4d located on the left side of the vehicle, and also to the rear air The supply port 14 is passed through the rear (Ql17) cylinder part 4bσ] exhaust bow) 4dCM located on the left side of the vehicle through the hose 18. The cylinder portion 4a is provided with four boat communication holes 4ee4f, which pass through the wall surface of the cylinder head and communicate with each boat 4dK, at a distance of 1Vc from each other. V-, the open end of each port communication hole 114f is closed with a plug 4g. and the hose 17
, 18 has a communication hole A (communicated with the intersection of the port communication holes 4e and 4f, and an exhaust bow via the boat communication holes 4e and 4ft) bored in the cylinder part 4as4b.
dK is in communication). ! A junction pipe 19 is provided.

The connecting pipe 19 is l! ! It has a flange part 19at that comes into contact with the opposite part a of the through hole A, and is connected to the flange 20, retainer f21, and fixing plate 22.
It is screwed airtightly to b.

The IIu sub-valve 16 is a cup 11% attached to one end of the casing 16av forming the air passage chamber 15t.
a and the diaphragm 16b held between the cover lRa and the casing 15a form a sealed chamber 1fSC, and the sealed chamber 1'PI C! ? Tube 16d.

Hose 166 etc. t-through engine σ] Throttle 1F
The valve body 1flf, which is connected to the downstream intake pipe 4h, is caused to reciprocate by the negative pressure of the @fiLW4h, the force of which is fixed at one end on the diaphragm 1flb. g] When the negative pressure becomes 1 large, the diaphragm iab force moves to the right in FIG. 15a
The air intake port 12 and the air supply port 14 are disconnected from each other by contacting the inner contact surface 15b, thereby stopping the air supply to the exhaust port 4d. In addition, at a position corresponding to the air intake port 12 of the base portion 8a of the air cleaner case 80, there is a hole located above the carburetor 90 installation port 9a which is located inside the base 1% 8a. 'Prominent communication'
f8b is integrally molded. This communication pipe 8b allows air to flow into the secondary air supply bag device 10 through the inlet port 9a.
This prevents this mixed gas from flowing into the secondary air supply bag 10 even if the gas containing fuel is blown back from the carburetor 9. The secondary air supply device 1O has the following configuration: - When the engine decelerates when unburned gas is likely to be included in the exhaust gas, the control valve 16 cuts off the communication between the air intake port 12 and the air supply port 14 and closes the exhaust bow. The IFF air supply to 4d is stopped to prevent afterburn (afterfire) from occurring in the exhaust pipe.When not decelerating, the air intake port 12 and air supply port 14 are communicated with each other to prevent the occurrence of afterburn in the exhaust pipe. Fresh air is supplied to port 4d, and Hc, co, etc. in the exhaust gas are
)Convert to 1.0°CO. ■Tako's secondary air supply device TL.

Are the VM Engine 4 mutually V-shaped? Since the secondary air supply bag [10] is placed in the empty space 5 created on the side of the cylinder when the cylinder 7 is set, the secondary air supply bag [10] does not protrude too much from the full width W of the engine noise, and therefore the air supply bag [10]
By installing the secondary air supply M@IO, the overall width of the engine is expanded and the low engine speed is not impaired. This is a device that supplies fresh air from
For example, a secondary air supply device l is provided above the O.

Piping, etc. of a separate member that communicates between the air cleaner case 8 and the air cleaner case 8? Although it is not necessary to provide it, it is easy to make it compact. The secondary air supply device 10 and the exhaust port 4d are arranged close to each other, and the secondary air supply device 1110 and the exhaust port 4d are arranged close to each other.
Since the flow path communicating with 4d is shortened, flow path resistance is reduced (even at low engine speeds with little exhaust pulsation, sufficient fresh air is supplied to the exhaust boat, resulting in efficient exhaust gas treatment). becomes possible.

In the above-described embodiments, the case where the engine is V-type has been described, but the present invention can also be applied to a case where the engine is of the same type horizontally and the opposing cylinders are offset from each other in the direction of the crankshaft axis. In that case, the space behind the cylinder located closer to the front end of the crankshaft axis and the space in front of the cylinder located closer to the rear end is the empty space 5. in the above embodiment. This corresponds to Fl.

As explained above, the secondary air supply device according to the present invention is constructed by shifting the cylinders located on one side and the other side with respect to the axis of the crankshaft in the direction of the axis of the crankshaft of the engine. Due to the misalignment along
One device is installed in a space formed between the crankshaft end position +t of the cylinder on the negative side and the cylinder on the other side. Therefore, the secondary air supply H1it does not protrude significantly from the overall width of the engine, and even when applied to a vehicle such as a motorcycle,
The appearance of the secondary air supply device is not impaired, and the compactness of the engine is not sacrificed. The open cylinder and the secondary air supply device are placed close to each other, and the piping that connects the exhaust system such as the exhaust port with the secondary air supply device is short, and the flow path resistance is reduced to 8. Sufficient FLRT even at low engine speeds with little pulsation
L can be supplied to the exhaust fi yarn and O enables efficient exhaust gas treatment.

[Brief explanation of the drawing]

FIG. 1 is a book view showing an embodiment of a motorcycle to which the present invention is applied, #! Fig. 3 is a cross-sectional view taken along line I-1 in Fig. 1. Fig. ψ is a cross-sectional view taken along line N-IV in Fig. 1. 0 4°...°...V-type engine, 4a# 4b...
・Cylinder part, 4d...Exhaust port, 4h...
...Intake pipe, 5, 6...Vacancy, Air cleaner case for 8, Base part for 8a, 8b...
...Continuation'! ? , 9...Carburetor,
9a...Intake port, 10.11...River/secondary air supply device 6% 1z...Air intake port, 18...
... Reed valve, 14 ... Air supply port, 15
... Air passage chamber b 15a ... Casing, L5b ... Contact surface, 16 ... Control valve 0 Applicant Honda Motor Co., Ltd.

Claims (1)

[Claims] The cylinders on one side and the other side of the engine are formed by shifting the cylinders located on one side and the other side with respect to the axis of the crankshaft. Cylinder crank 4! A secondary air supply device for an engine, characterized in that a secondary air supply and a supply bag U for supplying primary air to an exhaust system are arranged in a space created at an end position U.