JPH0720346Y2 - Exhaust control device for 2-cycle engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an exhaust control device for a two-cycle engine, and more specifically, to an exhaust capacity varying device and an exhaust timing varying device, and an actuator for operating a valve element of these varying devices. The present invention relates to the structure of the actuator in the exhaust control device for a two-cycle engine.

[Conventional technology]

An exhaust control device for a two-cycle engine equipped with an exhaust volume variable device and an exhaust timing variable device is adopted in, for example, a two-cycle engine mounted on a motorcycle, and FIG. The cycle engine 1 is shown conceptually.

The exhaust volume changing device 10 is a chamber communicating with the exhaust passage 2.
A valve body 12 is formed between the exhaust passage 2 and the chamber 11 while forming the valve 11, and the valve body 12 is opened in the low speed range of the engine 1 and closed in the medium and high speed range. The exhaust pulsation is matched by.

Further, the variable exhaust timing device 20 disposes the valve body 21 in and out of the exhaust passage 2 and projects the valve body 21 in the low-medium speed rotation range of the engine 1 so that the upper portion of the exhaust port 3 is provided. Is closed to slow down the exhaust timing, immerse the engine 1 in the high-speed engine speed range, open the upper part of the exhaust port 3 to accelerate the exhaust timing, and obtain the optimum compression ratio in each engine speed range. .

By the way, the valve body 12 in the exhaust volume variable device 10,
As an actuator for operating the valve body 21 in the exhaust timing varying device 20, the crankshaft 4 is driven when the number of rotations exceeds a predetermined value, and a rotating plate is used by utilizing the rotational force of the shaft 4. Is rotated by a predetermined angle, the rotational movement of the plate is transmitted to the valve elements 12 and 21 via a link, and the valve elements 12 and 21 are operated accordingly.

However, the preferable operation timings of the valve bodies 12 and 21 do not always match. Therefore, in order to operate the valve bodies 12 and 21 with one actuator, a delay mechanism or the like is interposed between the valve bodies 12 and 21 or the operation timing is shifted.
It is necessary to operate each valve body 12 and 21 independently by one actuator.

However, in the former case, the delay mechanism becomes complicated and there is a possibility that the reliability may be reduced accordingly. In the latter case, the actuator becomes large and it is disadvantageous for making the engine compact.

[Purpose of device]

An object of the present invention is to provide an exhaust control device for a two-cycle engine that can achieve miniaturization as much as possible.

[Constitution of device]

The exhaust control device for a two-cycle engine according to the present invention is
An actuator having the following structure is provided.

That is, the actuator is supported by a support shaft arranged in parallel with the crankshaft and driven and rotated by the rotation of the crankshaft, and a fixed plate supported by the support shaft in one side area of the fixed plate. A first movable plate that is moved in the axial direction of the support shaft by a centrifugal force that acts on the support shaft, and a first movable plate that is supported by the support shaft in a lateral region that does not face the fixed plate of the first movable plate. And a first rotating plate that is rotated based on the movement of the first movable plate by cam means interposed between the first rotating plate and the first movable plate.

The actuator is supported by the support shaft in the other side area of the fixed plate and is moved in the axial direction of the support shaft by the centrifugal force acting on the fixed plate, and the second movable plate. A first bearing which is supported by a support shaft in a side area not facing the fixed plate of the plate and which is pivoted based on the movement of the second movable plate by cam means interposed between the plate and the second movable plate. And two rotating plates.

Further, the first rotating plate of the actuator is linked to the valve body of the exhaust volume variable device, and the end of the actuating rod whose end is bent outwardly faces the first movable plate. The second rotating plate of the actuator is connected to the side surface and supported, while the second rotating plate of the actuator is linked to the valve body of the exhaust timing varying device and has the end portion of the actuating rod bent outwardly. , The second movable plate is supported by being connected from the side surface facing the second movable plate.

〔Example〕

Hereinafter, a specific example of the present invention will be described based on FIG. 1 showing an actuator in an exhaust control device of a two-cycle engine according to the present invention and FIG. 2 conceptually showing an overall configuration of the exhaust control device according to the present invention. This configuration will be described in detail.

The actuator 30 is arranged on an idle shaft support shaft 5 arranged in parallel with the crank shaft 4. This actuator 30
Has a fixed plate 31 in the center of the shaft 5, and the fixed plate 31 is shared by an actuator mechanism 30a for an exhaust capacity varying device and an actuator mechanism 30b for an exhaust timing varying device on the left and right in FIG. Has been done.

The actuator mechanism 30a has a first movable plate 32 disposed in one side area (left area in the first) with respect to the fixed plate 31. The movable plate 32 is engaged with the shaft 5 by a spline or the like, and is installed so as to be movable in the axial direction of the shaft 5. A flange 5a is formed on the shaft 5, and a spring 33 is interposed between the flange 5a and the movable plate 32, and the movable plate 32 is constantly urged toward the fixed plate 31 by the spring 33. A space is formed between the movable plate 32 and the fixed plate 31, and a ball 34 as a centrifugal weight is accommodated in the space. On the side walls of the movable plate 32 and the fixed plate 31 which form the space, tapered surfaces 32a, 31a are formed which approach each other toward the outside in the radial direction. Further, in a lateral region (left region in the first) that does not face the fixed plate 31 with respect to the first movable plate 32, a first rotating plate is arranged side by side with the first movable plate 32.
35 are provided. The shaft 5 is rotatably supported by the rotary plate 35, the needle bearing 36, etc., and a thrust bearing 37 is interposed between the rotary plate 35 and the movable plate 32. A cam groove 35a is formed on the side surface of the rotating plate 35. A ball holder 38 is fixedly installed at a position facing the cam groove 35a of the rotating plate 35, and the ball 39 held by the holder 38 is housed in the cam groove 35a. Also,
One end of the operating rod 40 is engaged with the peripheral edge of the first rotating plate 35. One end of the operating rod 40 is bent toward the outer side (left side in FIG. 1) in an L shape, and is supported by being connected from a side surface of the rotating plate 35 facing the movable plate 32. The other end of the rod 40 has a valve body operating lever 41 as shown in FIG.
Is engaged with.

On the other hand, the actuator mechanism 30b has substantially the same configuration as the actuator mechanism 30a, and the fixing plate 3
It has a second movable plate 42 arranged in the other lateral region (the right region in the first) with respect to 1. The movable plate 42 is engaged with the shaft 5 by a spline or the like,
It is installed so that it can move in the axial direction. A circlip 5b is locked to the shaft 5, and a spring 43 is interposed between the circlip 5b and the movable plate 42, and the movable plate 42 is constantly urged toward the fixed plate 31 by the spring 43. There is. A space is formed between the movable plate 42 and the fixed plate 31, and a ball 44 as a centrifugal weight is accommodated in the space. On the side walls of the movable plate 42 and the fixed plate 31 that form the space, the tapered surfaces 42a that approach each other radially outward,
31b is formed. Further, a second rotating plate 45 is arranged side by side with the second movable plate 42 in a lateral region (right region in the first) that does not face the fixed plate 31 with respect to the second movable plate 42. ing. This rotating plate 45 is
It is rotatably supported on the shaft 5 by a need bearing 46 and the like, and a thrust bearing 47 is interposed between the rotating plate 45 and the movable plate 42. A cam groove 45a is formed on the side surface of the rotating plate 45. A ball holder 48 is fixedly installed at a position facing the cam groove 45a of the rotating plate 45, and the ball 49 held by the holder 48 is housed in the cam groove 45a.
Further, the operation rod is provided on the peripheral portion of the second rotating plate 45.
One end of 50 is engaged. One end of the operating rod 50 is bent and formed in an L shape toward the outer side (right side in FIG. 1) and is supported by being connected from the side surface of the rotating plate 45 facing the movable plate 42. Is
The other end of the rod 50 is engaged with the valve body operating lever 51 as shown in FIG.

In the actuator, a gear 31c is formed on the peripheral surface of the fixed plate 31, and the gear 31c is connected to the crankshaft 4
Of the gear 4a. Further, in the above actuator, the spring constant of the spring 43 is made larger than the spring constant of the spring 33, and the set pressure of the spring 43 is made larger than that of the spring 33.

The operation of the actuator will be described below.

In the low speed range of the engine 10, as shown in FIG. 1, the balls 34 and 44 are located closest to the shaft 5, and as shown in FIG. Disc 12
Is opened, the exhaust passage 2 and the chamber 11 are communicated with each other, the valve body 21 of the exhaust timing varying device 20 is projected, and the upper portion of the exhaust port 3 is closed.

When the rotational speed of the engine 10 increases to reach the medium speed rotational speed range, the balls 34 are moved by the centrifugal force generated by the rotation of the shaft 5 into the shaft 5
Moved away from the movable plate
32 is moved to the left in FIG. The movable plate 32 acts on the rotating plate 35 via a thrust bearing 37. Then, the rotating plate 35 is rotated by the cam means including the cam groove 35a and the ball 39. Therefore, the rod 40 is pushed in the direction of the arrow in FIG. 2, and the valve body 12 is rotated in the direction of the arrow via the lever 41 to close the space between the exhaust passage 2 and the chamber 11.

Further, when the rotation speed of the engine 10 increases and reaches the high-speed rotation speed range, the ball 44 is moved in the direction away from the shaft 5,
As a result, the movable plate 42 is moved to the right in FIG. This movable plate 42 is a thrust bearing 47.
It acts on the rotating plate 45 via. Then, the rotating plate 45 is rotated by means including the cam groove 45a and the ball 49. Therefore, the rod 50 is pushed in the direction of the arrow in FIG. 2, and the valve body 21 is moved in the direction of the arrow via the lever 51 to open the upper portion of the exhaust port 3. Of course, in the high speed rotation range of the engine 10, the valve body 12 is maintained in the closed state.

[Effect of device]

As described above in detail, in the exhaust control device for a two-cycle engine according to the present invention, the first movable plate and the first rotating plate, which are arranged with the fixed plate in the actuator interposed therebetween, and the second movable plate. Plate and second
Since the valve plates of the exhaust capacity varying device and the exhaust timing varying device are independently operated by the rotating plate of FIG. 1, it is possible to compare with the conventional technology using the delay device and the two actuators. It is possible to achieve a compact size.

Also, an operating rod linked to the valve body of the exhaust volume variable device,
And the operating rods linked to the valve element of the exhaust timing varying device are connected from the sides of the first rotating plate and the second rotating plate that face the movable plate, that is, from the inside of each rotating plate, It is possible to achieve further miniaturization of the exhaust control device without the above operating rods protruding outward.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an actuator in an exhaust control system for a two-cycle engine according to the present invention, FIG. 2 is an overall conceptual view showing an exhaust control system for a two-cycle engine according to the present invention, and FIG. 3 is an exhaust system. It is a conceptual sectional view of a two-cycle engine provided with a capacity device and an exhaust timing variable device. 30 …… actuator, 30a …… actuator mechanism, 3
0b: Actuator mechanism, 31: Fixed plate, 32 ...
… Movable plate, 33 …… Spring, 34 …… Ball, 35
...... Rotating plate, 35a …… Cam mechanism, 39 …… Ball, 4
2 ... Movable plate, 43 ... Spring, 44 ... Ball, 45 ... Rotating plate, 45a ... Cam groove, 49 ... Ball.

Claims (1)

[Scope of utility model registration request] 1. An exhaust control device for a two-cycle engine, comprising an exhaust capacity varying device and an exhaust timing varying device, a valve body of the exhaust volume varying device, and an actuator for operating the valve body of the exhaust timing varying device. A fixed plate supported by a support shaft arranged in parallel with the crankshaft and driven and rotated based on the rotation of the crankshaft, and supported by the support shaft in one lateral region of the fixed plate. And a first movable plate that is moved in the axial direction of the support shaft based on a centrifugal force that acts on the fixed plate, and the support shaft in a lateral region of the first movable plate that does not face the fixed plate. Is pivoted on the basis of movement of the first movable plate by cam means interposed between the first movable plate and the first movable plate. And an end portion of the actuating rod which is linked to the valve body of the exhaust volume varying device and whose end portion is bent outwardly, is supported by connecting from the side surface facing the first movable play. No. 1 rotation plate and a second movable member supported on the support shaft in the other side region of the fixed plate and moved in the axial direction of the support shaft based on the centrifugal force acting on the fixed plate. The second movable plate is supported by the support shaft in a lateral region of the second movable plate that does not face the fixed plate, and the second means is provided by a cam means interposed between the second movable plate and the second movable plate. The end portion of the operating rod that is pivoted based on the movement of the movable plate, is linked to the valve body of the exhaust timing varying device, and has the end portion bent outwardly is connected to the second movable plate. An exhaust control device for a two-cycle engine, comprising: an actuator including a second rotating plate connected to and supported from a side surface opposite to the second rotating plate.