JPH1136844A - Exhaust muffler incorporated with valve for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent switch hammering of a control valve caused by the pulsation pressure by forming the control valve which is opened and closed according to the increases and decrease of the pipe internal pressure, with a first valve for closing an opening edge of an inner pipe, a second valve for closing an opening edge of an enlarged pipe and a connection rod for integrally connecting the first and the second valves. SOLUTION: A control valve A included in an exhaust muffler is mounted on an opening edge at the first chamber side of a second inner valve 17 which communicates with a first chamber 19 and a third chamber 21 of the exhaust muffler, the second inner pipe 17 is mounted over a first buffle plate 13 and a second buffle plate. This control valve A is fixed on an edge part of the inner pipe 17, and comprises an enlarged pipe 1 having an inner diameter D larger than an inner diameter (d) of the inner pipe 17, a first valve 2 for closing an opening edge of the inner pipe 17, a second valve 3 for closing an opening edge 1a of the enlarged pipe 1, a connection rod 4 for integrally connecting the first valve 2 and the second valve 3, and a spring 5 for pressing the first valve 2 to an opening edge 17a of the inner pipe 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of an exhaust muffler with a built-in valve for an automobile, in which a control valve that opens and closes in accordance with an increase and decrease of the pressure in the pipe is provided at an end of an inner pipe opening into the muffler. Belong.

[0002]

2. Description of the Related Art Conventionally, as an exhaust muffler with a built-in valve for a vehicle, those described in, for example, JP-A-2-16317, JP-A-3-51124 and JP-A-5-98930 are known. Have been.

The structure of the conventional exhaust muffler with a built-in valve shown in FIG. 5 will be described. A control valve is mounted at an end of an inner pipe. The valve body is provided rotatably about a shaft, and a valve body is pressed against the open end of the inner pipe by a coil spring.

Therefore, when the force in the valve opening direction obtained by multiplying the pressure in the pipe by the pressure receiving area of the valve body exceeds the force in the valve closing direction by the coil spring, the valve body rotates about the rotary shaft and the valve is rotated. Opens.

[0005]

However, in the above-described conventional exhaust muffler with a built-in valve for a vehicle, when the pressure in the inner pipe is operated near the valve opening pressure, the pressure in the inner pipe changes finely up and down. There is a problem in that the pulsating pressure causes the valve body to repeatedly open and close and generate a tapping sound.

That is, since the pressure receiving area receiving the pressure in the inner pipe is a control valve structure with a single valve body that is constant regardless of whether the valve is opened or closed, even if the valve has a slight hysteresis characteristic due to a coil spring or the like, the valve is The valve opening pressure at which the valve starts to open and the valve closing pressure at which the valve opens are close to the same pressure level (valve opening pressure / valve closing pressure).

SUMMARY OF THE INVENTION It is an object of the present invention to provide an exhaust muffler with a built-in valve for a vehicle, which suppresses the opening / closing sound of a control valve due to a pulsating pressure during operation near a valve opening pressure or a valve closing pressure.

[0008]

[Means for Solving the Problems]

According to a first aspect of the present invention, there is provided an automobile valve having a control valve provided at an end portion of an inner pipe opening in a muffler, the control valve being opened and closed in accordance with increase and decrease of the pressure in the pipe. In the built-in exhaust muffler, the control valve is fixed to an end of the inner pipe, and an enlarged pipe having an inner diameter larger than an inner diameter of the inner pipe;
A first valve that closes an open end of the inner pipe, a second valve that closes an open end of the enlarged pipe, a connecting rod that integrally connects the first valve and the second valve, and an inner pipe that connects the first valve to the inner pipe. And a spring for applying a biasing force in the valve closing direction pressed against the open end of the valve.

According to a second aspect of the present invention, there is provided an exhaust muffler with a built-in valve for an automobile according to the first aspect of the present invention, wherein when the valve is fully closed, the second valve and the open end of the enlarged pipe are closed. It is characterized in that a slight gap is set between them.

According to a third aspect of the present invention, there is provided an exhaust muffler with a built-in valve for a vehicle according to the first or second aspect, wherein
The first valve and the second valve are characterized in that a spring retainer is fixed in a parallel arrangement, and a slide guide portion of a connecting rod is formed in the spring retainer.

According to a fourth aspect of the present invention, there is provided an exhaust muffler with a built-in valve for an automobile according to any one of the first to third aspects, wherein an enlarged pipe is provided on an outer peripheral portion of the second valve. A folded portion is formed so as to go around the outer peripheral position of the opening end.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

 Embodiment 1 First, the configuration will be described.

Embodiment 1 corresponds to the first, second and third aspects of the present invention.

FIG. 1 is a sectional view showing a control valve of an exhaust muffler with a built-in automobile valve according to the first embodiment. FIG. 2 is an overall sectional view showing the exhaust muffler with a built-in automobile valve of the first embodiment.

In FIG. 2, A is a control valve, 10 is a muffler shell, 11 is a front end plate, 12 is a rear end plate, 13 is a first baffle plate, 14
Is a second baffle plate, 15 is an exhaust inlet pipe, 16 is a first inner pipe, 17 is a second inner pipe, 18 is an exhaust outlet pipe, 19 is a first chamber,
Reference numeral 20 denotes a second chamber, and reference numeral 21 denotes a third chamber.

The control valve A is a valve that opens and closes as the pressure in the pipe increases and decreases.
The second inner pipe 17 that communicates with the first inner pipe 17 is disposed at the first chamber-side opening end.

The exhaust inlet pipe 15 includes a front end plate 11 and first and second baffle plates 1.
Exhaust gas from the engine is introduced into the second chamber 20 and the third chamber 21.

The first inner pipe 16 is provided on the first baffle plate 13, and has one end opened to the first chamber 19 and the other end opened to the second chamber 20.

The second inner pipe 17 is provided so as to bridge between the first baffle plate 13 and the second baffle plate 14. A control valve A is provided at one end opening to the first chamber 19, and the other end is provided at the other end. It is open to the third chamber 21.

The exhaust outlet pipe 18 is provided with a first
The baffle plate 13, the second baffle plate 14, and the rear end plate 12 are provided so as to penetrate therethrough. One end is open to the first chamber 19, and the other end is open to the outside air.

When the control valve A is closed, the first chamber 19 and the second chamber 20 are expansion chambers, and the third chamber 21 is a resonator chamber. When the control valve A is open, the third chamber 21 is closed.
Changes from the resonator room to the expansion room.

In FIG. 1, A is a control valve, 1 is an enlarged pipe, 2 is a first valve, 3 is a second valve, 4 is a connecting rod, 5 is a spring, 6 is a gap, 7 is a spring retainer, and 13 is a spring retainer. 1 baffle plate, 17 is the second inner pipe, 1
Reference numeral 9 denotes a first chamber, and reference numeral 20 denotes a second chamber.

The enlarged pipe 1 is fixed to an end of the second inner pipe 17 and has an inner diameter D larger than the inner diameter d of the second inner pipe 17.

The first valve 2 is provided with a second inner pipe 17
Is closed.

The second valve 3 is connected to the open end 1 of the expanded pipe 1.
Close a.

The connecting rod 4 connects the first valve 2 and the second valve 3 integrally.

The spring 5 applies an urging force in the valve closing direction to press the first valve 2 against the open end 17a of the second inner pipe 17.

As shown in FIG. 1, the gap 6 increases the degree of close contact between the first valve 2 and the opening end 17a of the second inner pipe 17 when the valve is fully closed.
Is set between the opening end 1a and the opening end 1a.

The spring retainer 7 is provided inside the enlarged pipe 1 to support the end of the spring 5.
The valve 2 and the second valve 3 are fixed in a parallel arrangement. The spring retainer 7 has a sliding guide portion 7a for guiding the sliding of the connecting rod 4 in the axial direction when the valve is opened and closed, and a differential pressure. A through hole 7b through which the exhaust gas passes is formed.

Next, the operation will be described.

When the engine speed is low or the load is low, the exhaust gas pressure of the second inner pipe 17 (hereinafter referred to as the inner pipe pressure) is low, and the inner pipe pressure and the exhaust gas receiving area of the first valve 2 are low. Is smaller than the spring force of the spring 5, the valve closed state of closing the opening 17a of the second inner pipe 17 with the first valve 2 is maintained (FIG. 1). At this time, due to the gap 6 set between the second valve 3 and the opening end 1a of the enlarged pipe 1,
The degree of close contact between the first valve 2 and the opening end 17a of the second inner pipe 17 is increased.

As the engine speed is increased by depressing the accelerator or the like, the pressure in the inner pipe increases, and the force obtained by multiplying the inner pipe pressure by the exhaust gas receiving pressure area of the first valve 2 is applied to the spring 5. When the spring force is slightly higher than the spring force, the spring 5 is compressed and the first valve 2 is opened (the inner pipe pressure at this time is the valve opening pressure).

When the first valve 2 opens even a little, the inside of the enlarged pipe 1 becomes the inner pipe pressure, and the first pipe 2 is opened.
Acting on the second valve 3 having a larger pressure receiving area than the valve 2, the first valve 2 and the second valve 3 connected by the connecting rod 4 start opening at a stretch, and the valve opening pressure and the exhaust gas of the second valve 3 The force multiplied by the pressure receiving area opens up to the valve opening amount that balances the spring force of the spring 5. Thereafter, when the inner pipe pressure further increases, the valve opening amount is increased in accordance with the valve opening characteristics of the second valve 3, and the valve is fully opened with a large opening area at the stroke limit.

When the pressure in the inner pipe decreases due to the accelerator return operation or the like in the fully opened state of the valve, the force for opening the second valve 3 decreases due to the pressure in the inner pipe, the spring 5 gradually extends, and the second valve 3 moves. When approaching the open end 1a of the enlarged pipe 1 and the inner pipe pressure further decreases and the second valve 3 and the open end 1a of the enlarged pipe 1 become a predetermined gap 6 (the inner pipe pressure at this time becomes lower). The first valve 2 closes the open end 17a of the second inner pipe 17, and the valve is fully closed.

As shown in FIG. 3, the valve opening pressure characteristic of the control valve A with respect to the pressure in the inner pipe is such that the valve opening pressure is defined by the first valve 2 having a small pressure receiving area. The valve closing pressure is defined by the second valve 3 having a large pressure receiving area, so that the valve closing pressure has a low pressure level, and a wide hysteresis width is provided between the valve opening pressure and the valve closing pressure.

Therefore, during the operation in which the pressure in the inner pipe is close to the valve opening pressure or the operation in which the pressure in the inner pipe is close to the valve closing pressure, even if the pressure in the inner pipe fluctuates due to the pulsating pressure, if the valve is open. As long as there is no pressure change larger than the hysteresis width, the valve is kept open, and if the valve is closed, the valve is kept closed unless there is a pressure change larger than the hysteresis width.
The opening and closing hitting sound corresponding to a is suppressed.

Next, the effects will be described.

(1) The control valve A is fixed to the end of the second inner pipe 17, and the enlarged pipe 1 having an inner diameter larger than the inner diameter of the second inner pipe 17 and the open end 17a of the second inner pipe 17 are A first valve 2 for closing, a second valve 3 for closing the open end 1a of the enlarged pipe 1, a connecting rod 4 for integrally connecting the first valve 2 and the second valve 3, and a second valve 2
Since the spring 5 for applying a biasing force in the valve closing direction to be pressed against the opening end 17a of the inner pipe 17 is provided, a large hysteresis is provided between the valve opening pressure and the valve closing pressure, and the valve opening pressure and the valve closing pressure are close to or close. It is possible to provide an exhaust muffler with a built-in valve for a vehicle, which suppresses the opening / closing sound of the control valve A due to the pulsating pressure during operation near the pressure.

(2) When the valve is fully closed, a slight gap 6 is set between the second valve 3 and the opening end 1a of the enlarged pipe 1, so that the first valve 2 and the second valve 2 are fully closed when the valve is fully closed. High adhesion to the opening end 17a of the inner pipe 17 can be secured.

(3) The first valve 2 and the second valve 3 are fixed to the enlarged pipe 1 in parallel with each other, and the spring retainer 7 is fixed, and the sliding guide 7a of the connecting rod 4 is formed in the spring retainer 7. Therefore, a stable valve opening / closing operation in which the first valve 2 and the second valve 3 do not tilt when the valve is opened / closed can be secured.

(Embodiment 2) First, the configuration will be described.

Embodiment 2 corresponds to the first, second, third and fourth aspects of the present invention.

FIG. 4 is a sectional view showing a control valve of the exhaust muffler with a built-in valve for a vehicle according to the second embodiment.

In FIG. 4, A 'is a control valve, 1 is an expansion pipe, 2 is a first valve, 3 is a second valve, 4 is a connecting rod, 5 is a spring, 6 is a gap, 7 is a spring retainer, and 13 is a spring retainer.
Is the first baffle plate, 17 is the second inner pipe,
19 is a first chamber, and 20 is a second chamber.

The difference from the first embodiment is that a folded portion 3a is formed on the outer peripheral portion of the second valve 3 so as to go around the outer peripheral position of the open end 1a of the enlarged pipe 1.

The other structure is the same as that of the first embodiment.

Operationally, by increasing the pressure receiving area of the second valve 3 from that of the first embodiment, the valve opening amount characteristic diagram of FIG.
As indicated by the dashed-dotted line characteristic, the valve is fully opened just by slightly increasing the inner pipe pressure from the valve opening pressure, and the responsiveness of the fully opened valve is further improved.

(Other Embodiments) In the first embodiment, an example of application to the exhaust muffler with a built-in valve for a vehicle shown in FIG. 2 has been described. However, in the case of an exhaust muffler having an inner pipe opening in the muffler, FIG. Needless to say, the present invention can be applied to an exhaust muffler having a structure other than 2.

[0049]

According to the first aspect of the present invention, an exhaust valve with a built-in valve for an automobile is provided with a control valve that opens and closes as the pressure in the pipe increases or decreases at the end of the inner pipe that opens into the muffler. In the muffler, the control valve
An enlarged pipe fixed to an end of the inner pipe and having an inner diameter larger than the inner diameter of the inner pipe; a first valve for closing an open end of the inner pipe; a second valve for closing an open end of the enlarged pipe; A connecting rod that integrally connects the second valve and a spring that applies a biasing force in the valve closing direction that presses the first valve against the open end of the inner pipe are provided. It is possible to provide an exhaust muffler with a built-in valve for a vehicle, which suppresses the opening / closing sound of the control valve due to the pulsating pressure during operation in the vehicle.

In the invention according to claim 2, claim 1
In the exhaust muffler with a built-in valve for a vehicle according to the present invention, when the valve is fully closed, a slight gap is set between the second valve and the opening end of the enlarged pipe. When the valve is fully closed, high adhesion between the first valve and the open end of the inner pipe can be secured.

According to the third aspect of the present invention, there is provided the first aspect.
In the exhaust muffler with a built-in valve for a vehicle according to claim 2, the first valve and the second valve are fixed to the enlarged pipe in a parallel arrangement with the spring retainer, and the sliding guide of the connecting rod is fixed to the spring retainer. Claim 1
Alternatively, in addition to the effect of the invention described in claim 2, it is possible to secure a stable valve opening / closing operation in which the first valve and the second valve do not tilt when the valve is opened / closed.

In the invention according to claim 4, claim 1 is
In the exhaust muffler with a built-in valve for a vehicle according to the third aspect, the folded portion is formed on the outer peripheral portion of the second valve so as to go around the outer peripheral position of the opening end of the enlarged pipe. In addition, the valve fully open response can be further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a control valve of an exhaust muffler with a built-in automotive valve according to a first embodiment.

FIG. 2 is an overall sectional view showing a control valve of the exhaust muffler with a built-in valve for a vehicle according to the first embodiment;

FIG. 3 is a characteristic diagram of a valve opening amount with respect to an inner pipe pressure in a control valve according to the first embodiment.

FIG. 4 is a sectional view showing a control valve of an exhaust muffler with a built-in valve for a vehicle according to a second embodiment;

FIG. 5 is an overall sectional view showing a conventional exhaust muffler with a built-in valve for a vehicle.

[Explanation of symbols]

 A control valve 1 enlarged pipe 1a open end 2 first valve 3 second valve 3a folded part 4 connecting rod 5 spring 6 gap 7 spring retainer 7a sliding guide part 13 first baffle plate 17 second inner pipe 17a open end

Claims (4)

[Claims] 1. An inner pipe (1) opening into a muffler.
7) In an exhaust muffler with a built-in valve for a vehicle, which is provided with a control valve (A) that opens and closes in accordance with an increase or decrease in the pressure in the pipe at the end of (7), the control valve (A) is connected to An enlarged pipe (1) fixed to the portion and having an inner diameter (D) larger than the inner diameter (d) of the inner pipe (17); and a first valve (2) for closing an open end of the inner pipe (17).
A second valve (3) for closing an open end (1a) of the enlarged pipe (1); and a connecting rod (4) for integrally connecting the first valve (2) and the second valve (3). A spring (5) for applying a biasing force in the valve closing direction for pressing the first valve (2) against the open end (17a) of the inner pipe (17). Exhaust muffler. 2. The exhaust muffler with a built-in valve for a vehicle according to claim 1, wherein when the valve is fully closed, a slight gap (6) is provided between the second valve (3) and the open end (1a) of the enlarged pipe (1). (4) An exhaust muffler with a built-in valve for a vehicle, wherein 3. The exhaust muffler with a built-in valve for a vehicle according to claim 1, wherein the expansion pipe (1) has a first valve (2) and a second valve (3).
A spring retainer (7) is fixed in a parallel arrangement, and a sliding guide (7a) for a connecting rod (4) is formed on the spring retainer (7). . 4. The exhaust muffler with a built-in valve for a vehicle according to claim 1, wherein the exhaust valve extends around an outer peripheral portion of the second valve (3) to an outer peripheral position of an opening end (1a) of the enlarged pipe (1). An exhaust muffler with a built-in valve for an automobile, wherein a folded portion (3a) is formed.