JPH0452412Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an engine intake system in which a rotary valve having a cylindrical valve body is interposed in an intake passage.

(Prior Art) It has been known that a rotary valve is installed in the intake passage of an engine for various purposes.
For example, as seen in Special Publication No. 58-55329,
2. Description of the Related Art An engine intake system is known in which an intake passage is closed by a rotary valve earlier than the intake valve closes during low load to reduce pumping loss.

(Problem to be solved by the invention) When a plurality of intake passages are opened and closed by the rotary valve as described above, it is necessary to open and close the plurality of passages with a single valve. However, reducing the clearance between the valve body and the outer casing of a rotary valve is difficult due to deformation or vibration, etc., and machining is difficult. Communication between the passages may occur, and the desired function may not be obtained.

Furthermore, when a sealing material is attached to the outer periphery of the valve body between the openings formed in the valve body of a rotary valve in order to open and close a plurality of intake passages, this sealing material increases the driving resistance for rotating the valve body. This results in a decrease in operational response or an increase in the size of the drive device.

As described above, a rotary valve having a valve body interposed in an intake passage is required to be lighter and stronger, and it is also necessary to improve reliability by ensuring stable operation.

Therefore, in view of the above circumstances, the present invention opens and closes the two intake passages with a single rotary valve, thereby reducing the valve driving force and achieving stable operation and reliability while ensuring sealing performance between both intake passages. It is an object of the present invention to provide an intake device for an engine as described above.

(Means for Solving the Problems) The intake system of the present invention is provided with a single rotary valve that spans two intake passages and has two openings for opening and closing each intake passage. The valve body is characterized in that one bearing part using a rolling bearing that supports the valve body on the valve casing is disposed only between two openings of the valve body.

(Function) A rolling bearing is used only between the openings in the valve body of the rotary valve that opens and closes the two intake passages.
Two bearings are provided, and the valve body is supported by the bearings, and the bearings ensure sealing between the passages on both sides.Since the bearings are supported at the middle part of the valve body, the casing is caused by the deflection of the valve body. This prevents collisions with other parts, resulting in high precision rotation and reduced clearance. In addition, by providing one bearing portion at the middle portion, compared to the case where bearing portions are provided at both ends, there is less driving resistance in the rotational operation of the rotary valve valve body, and the valve driving force can be reduced.

(Example) Hereinafter, an example of the present invention will be described along with the drawings. FIG. 1 schematically shows the overall structure of an intake system in a two-cylinder rotary piston engine, and FIGS. 2 and 3 show the specific structure.

An engine main body 1 (rotary piston engine) including a first cylinder A and a second cylinder B includes two rotor housings 2 and both rotor housings 2.
A rotor 5 rotates planetarily within a casing constituted by an intermediate housing 3 between them and two side housings 4 at both ends, and three combustion chambers 6 (operating Air is taken into the chamber from low-speed and high-speed intake ports 7 and 8 on both sides, the air-fuel mixture is ignited by a spark plug 9, and exhausted from an exhaust port 10.

Note that the intake ports 7 and 8 are connected to each cylinder A and B.
On the other hand, low-speed intake ports 7 are opened on both sides of the intermediate housing 3, and high-speed intake ports 8 are opened on the inner surface of the side housing 4, respectively.

Separate low-speed and high-speed intake passages 1 for supplying air-fuel mixture to the combustion chamber 6 for the intake ports 7 and 8
3 and 14 are connected. That is, the low speed intake port 7 of each cylinder is connected to the intermediate housing 3.
Independent low-speed intake passages 13, 13 are connected to the side housing 4, and independent high-speed intake passages 14, 14 are connected to the side housing 4, respectively.

The above independent intake passages 13, 1 for low speed and high speed
4 is composed of lower independent intake pipes 13a, 14a connected to one side of the engine body 1, upper independent intake pipes 13b, 14b connected thereto, and further upstream connecting intake pipes 13c, 14c. ,
The independent intake passages 13 and 14, which have one end communicating with the combustion chamber 6 as a whole, are shaped to extend away from one side of the engine body 1 and then curve upward toward the one side of the engine body 1. There is (second
(see Figures and Figure 3).

A low-speed fuel injection valve 15 is attached from above to the downstream portion of the low-speed independent intake passage 13 in the rotor housing 2 located below, and an upper independent intake pipe 14b constituting the high-speed independent intake passage 14 is installed from above. A high-speed fuel injection valve 16 is provided in the downstream portion. Fuel distribution pipes 17 and 17 are connected to the respective fuel injection valves 15 and 16, and fuel is supplied thereto. The low-speed fuel injection valve 15 achieves responsiveness by directly injecting fuel near the intake port 7, while the high-speed fuel injection valve 16 is installed on the upstream side to promote vaporization and atomization of the injected fuel. I'm trying to figure it out.

Further, the interval between the upper independent intake pipes 13b and 14b is widened, and the rotary valve 18 is formed between the upper independent intake pipes 13b and 14b for the cylinders A and B on both sides.
is installed. The rotary valve 18 is
As shown in FIG. 1, the low-speed independent intake passages 13, 13 and the high-speed independent intake passages 14, 14 of the cylinders on both sides are connected at predetermined times (at medium and high speeds).
The supercharging effect is obtained through the intake air interference effect between the cylinders.

As shown in FIG. 4, the details of the rotary valve 18 include a stepped shaft-shaped cylindrical valve body 20 rotatably fitted into a casing 19. The valve body 20 has a small diameter portion 21 with an opening 21a for opening and closing communication between the independent intake passages 13, 13 for low speed, and a large diameter portion 22a for opening and closing communication between the independent intake passages 14, 14 for high speed. The diameter portion 22 forms a stepped shaft shape. The valve body 20 is fitted into the cylindrical part 19a of the casing 19, and is inserted into the casing 19 between the opening 21a of the small diameter part 21 and the opening 22a of the large diameter part 22 on the outer periphery of the base of the small diameter part 21. It is rotatably supported by a bearing portion 23 which is a sealed bearing.
Further, the tip of the small diameter portion 21 is fitted into a recess 19c formed at the center of the bottom of the casing 19, and the shaft portion 24 erected at the center of the end face of the large diameter portion 22 is inserted into the center hole of the casing lid 19b. It penetrates and protrudes to the outside.

An actuator 25 formed by a diaphragm device is linked to the tip of the shaft portion 24 of the valve body 20, and is rotated to close both openings 21a and 22a at low speeds. The actuator 25 may be constructed of an electromagnetic actuator as shown in FIG. 1, and may be controlled to close at low engine speeds depending on the operating state (engine speed) using a drive signal from the control unit 26. .

Upper independent intake pipes 13b, 14b of the low-speed and high-speed independent intake passages 13, 14 are provided on both sides of the casing 19 of the rotary valve 18 at positions corresponding to the openings 21a, 22a of the valve body 20.
The upper connecting end of the downstream portion of the upper independent intake pipes 13b and 14b is
The low-speed and high-speed intake pipes are curved sideways and connected to face each other, while the upper independent intake pipe 1
The lower connection end portions of the upstream portions of 3b and 14b are curved from below and connected to the vicinity of the connection portion to the casing 19 of the downstream portion. Note that the upstream ends of the connecting intake pipes 13c and 14c are connected to the throttle body from a surge tank (not shown), and are connected to the throttle body for low speed and high speed.
(Fig. 1) are interposed respectively.

In the structure of the above embodiment, the installation direction is set so that when the rotary valve 18 is viewed from the side as shown in FIG. 2, its axial direction is parallel to the direction in which the intake pipes 13b and 14b are formed. This allows the overall height of the intake device to be made low. Furthermore, by connecting the upstream portions of the upper independent intake pipes 13b and 14b to the connecting portions of the casing 19 from below, space can be used effectively and the overall height can be reduced. . Furthermore, the structure of the connecting portion of the downstream portion of the upper independent intake pipes 13b, 14b to the casing 19 is as follows.
Low-speed side independent intake passage 1 with low intake flow rate and narrow diameter
The independent intake pipe 13b of No. 3 is on the inside and the high-speed independent intake passage 14b is on the outside, curved to the side, so that the pressure waves accompanying the opening and closing of the intake ports 7 and 8 can effectively direct the intake air of the other cylinder. It is formed so as to act on ports 7 and 8, and even if the radius of curvature of the low-speed independent intake pipe 13b, which has a small intake flow rate, becomes smaller inside, the effect of increasing intake resistance due to this is small.
The radius of curvature of the high-speed independent intake passage 14b with a large intake flow rate is increased to suppress an increase in intake resistance and to obtain good intake performance.

FIG. 5 shows another embodiment of the rotary valve,
It is a split type.

The valve body 32 of the rotary valve 30 has an opening 33 that opens and closes communication between the low-speed independent intake passages 13 and 13.
a small diameter portion 33 and a high-speed independent intake passage 1
The large diameter part 34 is formed separately from the large diameter part 34 provided with an opening 34a for opening and closing communication between the parts 4 and 14.
The protrusion 34b and the recess 33b of the small diameter portion 33 are integrated by fitting to form a stepped shaft shape. The valve body 32 is a cylindrical portion 31a of the casing 31.
is inserted into the opening 33a of the small diameter part 33 and the large diameter part 3.
The casing 31 is attached to the outer periphery of the base of the small diameter portion 33 (formed with a slightly small diameter) between the opening 34a of the
It is rotatably supported by a bearing part 35 which is a sealed bearing as a rolling bearing fitted into the bearing part 35 . Center protrusion 33c at the tip of the small diameter portion 33
is fitted into a recess 31c formed at the center of the bottom member 31b of the casing 31, and the shaft 36, which is erected at the center of the end face of the large diameter section 34, passes through the center hole of the casing lid 31d as in the previous example. protruding to the outside.

The rest is the same as the previous example, and the same components are given the same reference numerals.

FIG. 6 shows a rotary valve according to yet another embodiment, and is an example of a lightweight type.

The valve body 40 of the rotary valve 38 has an opening 41 that opens and closes communication between the low-speed independent intake passages 13 and 13.
and openings 42 for opening and closing communication between the high-speed independent intake passages 14, 14 on both sides, and recesses 40a, 40b are formed from both ends of the valve body 40 toward the center to reduce the weight of the valve body 40. is reduced. The valve body 20 is fitted into the cylindrical portion 39a of the casing 39,
Between the low-speed opening 41 and the high-speed opening 42, the valve body 40 is rotatably supported by a bearing portion 43, which is a sealed bearing as a rolling bearing and supported by the casing 39 against the outer peripheral surface of the valve body 40. There is. One end of the valve body 40 is fitted into a recess 39b formed at the center of the bottom of the casing 39, and the shaft 45, which is erected by a support member 44 at the center of the other end, is connected to the casing lid as in the previous example. It penetrates through the center hole of the portion 39c and protrudes to the outside.

The rest is the same as the previous example, and the same components are given the same reference numerals.

In addition to the embodiments described above, rotary valves for opening and closing two intake passages are used for various purposes, and the present invention is applicable to these rotary valves. In other words, for example, in order to change the dynamic effect of the intake air depending on the driving condition, the length of the intake passage can be shortened at high speeds and lengthened at low speeds, or by changing the length of the intake passageway for high speeds and medium speeds. A rotary valve is inserted in the communication passage to open the valve in each region, or when natural intake and supercharging are performed, the intake timing of supercharged air in each cylinder is controlled. For this reason, there are some systems in which a rotary valve is installed in the supercharging passage to open and close at a predetermined timing.

(Effects of the invention) According to the invention as described above, the valve body of the rotary valve is supported by one bearing portion made of a rolling bearing provided only between the openings for opening and closing the two intake passages, and this bearing In addition to ensuring sealing performance between the openings on both sides, deformation such as deflection of the valve body is absorbed by support in the middle part, and contact with the casing is prevented, thereby reducing clearance. In addition, without increasing the driving resistance due to the use of sealing materials, there is less driving resistance in the rotational operation of the valve body, and the valve driving force can be reduced.
The rotary valve and drive mechanism can be made more compact.

In particular, when attempting to simplify the structure so that two intake passages are opened and closed by a single rotary valve, communication between the passages can be prevented by improving the sealing performance between the openings, and the intake passage The desired opening and closing function can be obtained. This makes it possible to improve responsiveness and stable operation of the rotary valve, improve reliability, and obtain desired characteristics as an intake device.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing the entire engine equipped with an intake system according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional side view of the engine according to the specific example of FIG. 1, and FIG. 4 is a sectional plan view of the rotary valve in FIG. 3, FIG. 5 is a sectional plan view of the rotary valve in another embodiment of the present invention, and FIG. 6 is a sectional plan view of the rotary valve in another embodiment of the present invention. FIG. 3 is a cross-sectional plan view of a rotary valve in an example. 1...Engine body, 6...Combustion chamber, 13,1
4... Independent intake passage, 18, 30, 38... Rotary valve, 19, 31, 39... Casing,
20, 32, 40... Valve body, 21a, 22a, 3
3a, 34a...Opening, 23, 35, 43...Bearing portion, 41, 42...Opening.

Claims (1)

[Scope of utility model registration request] An intake system for an engine equipped with a single rotary valve that is provided across two intake passages and has two openings for opening and closing each intake passage, the valve body of the rotary valve being supported by a valve casing. An intake device for an engine, characterized in that one bearing portion using a rolling bearing is disposed only between two openings of a valve body.