JP3784158B2 - Intake device for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intake device for an internal combustion engine in which the length of an intake passage is variably set according to the rotational speed of the internal combustion engine (engine).
[0002]
[Prior art]
In general, in order to improve the engine torque, it is effective to set the intake manifold length longer during low-speed rotation and shorter during high-speed rotation using the intake inertia effect. As described above, various intake devices have been proposed in order to variably set the length of the intake manifold in accordance with the engine speed. For example, in Japanese Patent Laid-Open No. 60-1332023, a surge tank is constituted by using a rotating member, and the rotating member is rotated to change the position of a communication portion between the intake pipe and the intake air that leads to the engine. An air intake device capable of variably setting the length of the pipe is disclosed. Japanese Patent Application Laid-Open No. 59-188027 and Japanese Patent Application Laid-Open No. 62-214223 also disclose the same type of intake device.
[0003]
[Problems to be solved by the invention]
By the way, the intake device disclosed in the various publications described above rotates the position of the communication portion formed in the rotating member by rotating the rotating member housed in the housing. By the way, the housing for storing the rotating member has a complicated shape and is usually manufactured by molding. In recent years, the housing of the intake device is often formed of a resin material due to demands for weight reduction and cost reduction. However, since the dimensional accuracy of the housing manufactured by resin molding is not so good, the rotation of the rotating member described above is required. There is a possibility that the accuracy may be deteriorated or that good airtightness between the intake pipes constituting the intake manifold cannot be secured, and a sufficient intake inertia effect cannot be obtained. Further, when a housing is manufactured by molding, a method is generally used in which a housing is divided into two or more divided parts and then joined together by vibration welding or the like. However, in the housing manufactured by such a method, a step is likely to occur at the joint, and it becomes increasingly difficult to deteriorate the rotational accuracy and to ensure airtightness described above. Such a step generated in the joint portion occurs not only when the housing is manufactured by resin molding, but also when the housing is manufactured using a metal material such as aluminum.
[0004]
The present invention has been created in view of the above points, and an object of the present invention is to provide an intake air for an internal combustion engine that can ensure the dimensional accuracy of the rotation mechanism and can also ensure the airtightness between the intake pipes. To provide an apparatus.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, an intake device for an internal combustion engine according to the present invention includes a surge tank between a surge tank that variably sets the length of each intake pipe by rotation and a storage member that stores the intake tank. The enclosure member is provided as a separate part from the storage member, so that high machining accuracy can be maintained, and the rotation accuracy of the surge tank can be increased, and the surge tank and the storage can be stored. By narrowing the gap between the members, the airtightness between the intake pipes can be ensured.
[0006]
The surrounding member described above is preferably cylindrical. Since the surge tank as a rotating body generally has a cylindrical shape, when surrounding the surge tank, the surrounding member is also formed into a cylindrical shape, so that the rotational center of the surge tank can be obtained simply by enclosing the surge tank in the surrounding member. Therefore, it is easy to obtain high rotational accuracy. In addition, when the cylindrical members are combined, it becomes easy to manage the gap between them, and the airtightness between the intake pipes can be improved.
[0007]
Furthermore, the enclosing member described above, in addition to the case of forming a part of the sole is formed as a plurality of divided members to them to attach to correspond to each compartment positions of the intake pipes. Since the dividing members are arranged at the respective partition positions, the airtightness between the respective intake pipes is ensured in each. Further, instead of making the entire outer periphery of the surge tank face the inner peripheral surface of the surrounding member over a wide range, a collar portion that circulates around the outer periphery of the surge tank may be formed and brought into contact with the surrounding member. Since only the outer periphery of the flange portion of the surge tank is in contact with the surrounding member, the contact resistance is reduced, the surge tank can be rotated with a small rotational force, and the rotational drive portion can be reduced. This collar part can be easily generated by attaching a ring member to the outer periphery of the surge tank. In this case, the surge tank having the collar portion can be easily manufactured by attaching the ring member to the straight tubular member.
[0008]
Further, a groove portion may be formed around the outer periphery of the surge tank, and a ring member may be attached to the groove portion to form the above-described collar portion. In this case, by bringing the ring member into contact with the inner peripheral surface of the surrounding member, the gap between the surge tank and the surrounding member can be eliminated, and the airtightness between the intake pipes is maintained well. be able to.
[0009]
Moreover, in order to make it easy to assemble the surge tank, it is preferable that the above-described surrounding member has a thin one end and a thick other end to continuously or discontinuously change the diameter of the intermediate cylindrical surface. In addition, according to the present invention, even when the storage member is formed of a resin material and the dimensional accuracy is poor, good rotation accuracy can be obtained in the surge tank included in the surrounding member, and each intake pipe can be obtained. This is particularly effective when the housing member is made of a resin material.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In an engine intake device according to an embodiment to which the present invention is applied, a cylindrical member surrounding the surge tank is mounted outside a rotary cylindrical surge tank used for realizing a variable-length intake pipe. There is a special feature. Hereinafter, an engine intake device according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings.
[0011]
[First Embodiment]
FIG. 1 is a cross-sectional view showing the structure of an engine intake device according to a first embodiment to which the present invention is applied. 2 is a cross-sectional view taken along line II-II shown in FIG. As shown in FIGS. 1 and 2, the intake device 1 of the present embodiment includes a passage 10 for taking in intake air, and a surge tank 20 that is rotatably connected to the passage 10 through an opening 21. A cylindrical portion 40 as an enclosing member containing the surge tank 20, a housing 50 as a storage member to which the cylindrical portion 40 is fixed and four intake pipes 52 and a resonance chamber 54 are formed around the cylindrical portion 40; And a drive unit 70 that rotationally drives the tank 20.
[0012]
The surge tank 20 is a straight tubular cylindrical member, and is attached to be rotatable around a central axis. On the cylindrical surface of the surge tank 20, an opening 21 communicating with the passage 10, an opening 22 communicating with each intake pipe 52, and an opening 23 communicating with the resonance chamber 54 are formed. A plurality of groove portions 24 are formed in the circumferential direction on the outer peripheral surface of the surge tank 20 in correspondence with positions where the intake pipes 52 are partitioned, and a ring member for forming a flange portion in the groove portion 24 25 is loosely inserted.
[0013]
FIG. 3 is a view showing the shape of the outer peripheral surface of the surge tank 20. As shown in FIG. 2A, circumferential groove portions 24 are formed at six locations on the outer peripheral surface of the surge tank 20, and the ring members 25 shown in FIG. The ring member 25 has a notch portion 26, and is attached to each groove portion 24 on the outer peripheral surface of the surge tank 20 in a state where the notch portion 26 is expanded.
[0014]
A rotating shaft 28 is integrally formed at the center of the bottom surface portion 27 that is one end surface of the surge tank 20 and protrudes outward. The other end face of the surge tank 20 is joined with a lid 31 having a rotary shaft 29 and a gear 30 formed integrally around the rotary shaft 29.
The cylindrical portion 40 is fixed to the housing 50 so as to contain the surge tank 20, and the inner diameter dimension is accurately formed so that a substantially uniform gap is formed between the cylindrical portion 40 and the outer peripheral surface of the surge tank 20. Yes. The cylindrical portion 40 is in contact with the ring member 25 mounted on the outer peripheral surface of the surge tank 20, and the openings 21, 22, 23 formed in the surge tank 20 and passages except for the contact portion. 10, a large opening is formed so as not to hinder communication between the intake pipe 52 and the resonance chamber 54.
[0015]
The housing 50 is integrally formed with four spiral intake pipes 52, a passage 10, and a resonance chamber 54 so as to go around the cylindrical portion 40 joined inside. As shown in FIG. 2, each intake pipe 52 makes a circuit so as to cover the periphery of the included cylindrical portion 40, and an attachment portion 56 extending to the tip thereof is attached to the engine (not shown) with a bolt or the like. .
[0016]
FIG. 4 is a view showing the structure of the housing 50 including the cylindrical portion 40. As shown in the figure, the housing 50 includes a cylindrical portion 40, and positions 58 a, 58 b, 58 c that define the four intake pipes 52 formed on the inner periphery of the cylindrical portion 40 and formed in the housing 50. , 58d, 58e are in contact with the ring member 25 mounted in the groove 24 on the outer peripheral surface of the surge tank 20. In the cylindrical portion 40 other than the abutting portion, an opening 59 is formed over substantially the entire circumference so as not to prevent the communication between each intake pipe 52 and the opening 22 of the surge tank 20, and the passage 10 and the resonance chamber 54 are formed. Opening portions 60 and 61 are formed so as not to prevent communication with each other.
[0017]
The resonance chamber 54 is for reducing intake noise, and is attached so as to communicate with the surge tank 20 constituting a part of the intake passage in order to reduce resonance noise generated in response to engine rotation. In the intake device 1 of the present embodiment, the surge tank 20 and the resonance chamber 54 communicate with each other through the opening 23 formed in the surge tank 20 and the opening 61 formed in the cylindrical portion 40.
[0018]
Further, as shown in FIG. 1, when the shape of the opening 23 of the surge tank 20 is a triangular shape whose axial length varies along the circumferential direction, the opening 23 and the cylindrical portion 40 are formed. Since the cross-sectional area of the communication portion between the surge tank 20 and the resonance chamber 54 determined by the overlapping state with the opened opening 61 varies depending on the rotation state of the surge tank 20, a variable frequency type resonator is realized.
[0019]
Further, the drive unit 70 has a geared motor 74 housed and fixed in a cover 72 that also serves as a bearing portion of one rotating shaft 29 of the surge tank 20, and the lid of the surge tank 20 is interposed via this gear. The surge tank 20 is rotated by transmitting the rotational driving force to the gear 30 formed in the portion 31.
The intake device 1 of this embodiment has such a configuration, and the operation thereof will be described next. Air taken in from the intake port is sucked into the passage 10 from the intake port 12 via an air cleaner, a throttle, or the like (not shown), and introduced into the surge tank 20 through the opening 21. Since the opening 21 is formed over almost the entire circumference of the cylindrical surface of the surge tank 20, the opening is introduced into the surge tank 20 without resistance from the passage 10 regardless of the rotation state of the surge tank 20. The
[0020]
The air introduced into the surge tank 20 is distributed to the intake pipes 52 from the four openings 22 formed on the cylindrical surface of the surge tank 20, and is taken into the engine. Here, the circumferential positions of the four openings 22 are set so that the length of each intake pipe is optimized in accordance with the engine speed. The settable range of the opening 22 is the range indicated by the section A shown in FIG. 2, and the length from the opening 22 to the tip of each intake pipe 52 is changed by changing the circumferential position of the opening 22. Changes only in the section A. For example, the cross-sectional structure shown in FIG. 2 shows the position of the opening 22 when the length from the opening 22 to the tip of each intake pipe 52 is the longest, and corresponds to the low-speed rotation of the engine. The cross-sectional structure shown in FIG. 5 shows the position of the opening 22 when the length from the opening 22 to the tip of each intake pipe 52 is the shortest, and corresponds to the time of high-speed rotation of the engine. Since it is determined in advance how much the position of the opening 22 in the circumferential direction needs to be changed in accordance with the engine speed, a surge tank is instructed to rotate the motor 74 by an engine control unit (not shown) or the like. 20 is rotated by a predetermined amount, and the circumferential position of the opening 22 is set.
[0021]
As described above, the intake device 1 of the present embodiment includes the rotatable cylindrical surge tank 20 and changes the circumferential position of the opening 22 communicating with each intake pipe according to the engine speed. Thus, the length of each intake pipe 52 can be set variably, and the torque at each engine speed can be increased by utilizing the intake inertia effect.
[0022]
In addition, the intake device 1 described above does not directly hold the surge tank 20 in the housing 50 but holds the cylindrical portion 40 therebetween. Since the cylindrical portion 40 has a simple structure, it can be manufactured as a single component, and high dimensional accuracy of the inner peripheral surface containing the surge tank 20 can be ensured. Moreover, even when a plurality of parts are joined by welding or the like, it is easy to cut the inner diameter surface, and it is easy to increase the dimensional accuracy. Therefore, when the surge tank 20 is inserted and rotated inside the cylindrical portion 40, high rotation accuracy can be ensured. Further, when the housing 50 is manufactured by resin molding, the dimensional accuracy cannot be increased so much, but the rotation accuracy of the surge tank 20 and the airtightness between the intake pipes 52 are secured with the cylindrical portion 40. Therefore, the method of the present invention using the cylindrical portion 40 is particularly effective when the housing 50 is made of resin.
[0023]
Further, the ring member 25 attached to the groove portion 24 on the outer peripheral surface of the surge tank 20 is brought into contact with the inner peripheral surface of the cylindrical portion 40 at a position that partitions each intake pipe 52 with an urging force. And the inner peripheral surface of the cylindrical portion 40 can be almost eliminated, and sufficient airtightness can be secured between the intake pipes. Accordingly, it is possible to increase the torque at each engine speed by fully utilizing the intake inertia effect, and to obtain a high output from a low speed to a high speed.
[0024]
[Second Embodiment]
In the first embodiment described above, the cylindrical portion 40 is formed as a single component. However, since most of the portions corresponding to the intake pipes 52 are fastened by the openings 59, the intake pipes 52 You may make it replace with the division | segmentation cylindrical part as a some division | segmentation member divided | segmented by the corresponding part.
[0025]
FIG. 6 is a cross-sectional view showing the structure of an engine intake device according to a second embodiment to which the present invention is applied. FIG. 7 is a view showing the housing and the divided cylindrical portion included in the intake device shown in FIG. The intake device 2 shown in these drawings is different from the intake device 1 of the first embodiment described above in that the cylindrical portion 40 is replaced with a divided cylindrical portion, and description will be made focusing on this difference.
[0026]
As shown in FIG. 7, the divided cylindrical portions 40 a to 40 e of the present embodiment are divided into five parts so as to correspond to the divided positions of the four intake pipes 52, and each divided position of each intake pipe 52. Encapsulated and joined. In addition, each divided cylindrical portion 40a and the like are integrally formed with a flange portion 42 extending outward in the radial direction and used for positioning along the axial direction of the surge tank 20.
[0027]
In this manner, the divided cylindrical portions 40a to 40e are arranged at the partition positions of the intake pipes 52, and the ring member 25 mounted on the outer peripheral surface of the surge tank 20 is brought into contact with each of the divided cylindrical portions 40a and the like with a biasing force. By doing so, the gap between the ring member 25 and the inner peripheral surface of the divided cylindrical portion 40a and the like can be almost eliminated, so that the intake inertia effect can be fully utilized as in the intake device 1 of the first embodiment described above. Thus, the torque at each engine speed can be increased, and a high output can be obtained from a low speed to a high speed.
[0028]
In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, a plurality of groove portions 24 are formed on the outer peripheral surface of the surge tank 20, the ring member 25 is attached to each groove portion 24, and the outer periphery thereof is the inner periphery of the cylindrical portion 40, the divided cylindrical portion 40a, or the like. Although the surface abuts on the surface with a biasing force, the dimensional accuracy of the outer diameter of the groove 24 may be increased so that the inner diameter of each ring member 25 abuts on the outer diameter portion with a biasing force. Since the ring member 25 can be formed with high dimensional accuracy, the dimensional accuracy of the outer diameter of the ring member 25 is increased by fitting the ring member 25 into the groove portion 24 and restraining the inner diameter side. Therefore, the gap between the ring member 25 and the inner peripheral surface of the cylindrical portion 40 or the divided cylindrical portion 40a can be reduced, and the airtightness between the intake pipes 52 can be kept good.
[0029]
Further, the collar portion may be formed integrally with the surge tank 20 instead of using the ring member 25 as a separate member from the surge tank 20. For example, as shown in FIG. 8, when the surge tank 20 is molded, secondary injection molding is performed to form the surge tank body 20a and the collar portion 20b from different materials, so that the surge tank body 20a and the cylinder are formed. Even if the portion 40 and the like are formed of the same material, only the collar portion 20b is made of a different material. The surge tank 20 can be rotated.
[0030]
In the above-described embodiment, the motor 74 is rotated to transmit the rotational force to the rotating shaft 29 of the surge tank 20 via the gears. However, as shown in FIG. The rotary shaft 29 may be directly driven to rotate. Alternatively, a linear driving force generated using a vacuum actuator may be converted into a rotational force and used.
[0031]
In addition, in the intake devices 1 and 2 according to the present embodiment described above, the straight tubular surge tank 20 is used. However, considering the ease of assembly work and the like, the surge tank 20 and the cylindrical portion 40 on the non-motor side. The end portion may be narrowed and the motor side end portion may be thickened, and the diameter of the cylindrical surface may be changed continuously (in a so-called taper shape) or discontinuously (in multiple steps).
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a structure of an intake device for an engine according to a first embodiment.
FIG. 2 is a cross-sectional view taken along line II-II shown in FIG.
FIG. 3 is a view showing a shape of an outer peripheral surface of a surge tank.
FIG. 4 is a view showing a structure of a housing including a cylindrical portion.
FIG. 5 is a cross-sectional view of the intake device when the length of the intake pipe is changed.
FIG. 6 is a cross-sectional view showing a structure of an intake device for an engine according to a second embodiment.
7 is a view showing a housing and a divided cylindrical portion extracted from the intake device shown in FIG. 6; FIG.
FIG. 8 is a diagram showing another example of a surge tank.
FIG. 9 is a cross-sectional view showing a modified example of the intake device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Intake device 10 Passage 20 Surge tank 21, 22, 23 Opening part 40 Cylindrical part 50 Housing 52 Intake pipe 54 Resonance chamber 70 Drive part

Claims (6)

A plurality of compartmented intake pipes leading to each cylinder of the internal combustion engine;
A surge tank that has an opening for communication with the plurality of intake pipes, is rotatable, and changes the length of the intake pipe that communicates with the opening when rotated;
A storage member including at least a part of the intake pipe and storing the surge tank;
An enclosure member fixed inside the storage member and surrounding the surge tank ;
The enclosing member, an intake system for an internal combustion engine, characterized that you have been composed of a plurality of divided members disposed in correspondence with each compartment positions of the plurality of intake pipes. Oite to claim 1,
An intake device for an internal combustion engine, characterized in that a circumferential collar portion is formed on the outer periphery of the surge tank so as to correspond to each partition position of the plurality of intake pipes. In claim 2 ,
An intake device for an internal combustion engine, wherein the collar portion is formed by mounting a ring member on an outer periphery of the surge tank. In claim 2 ,
An intake device for an internal combustion engine, wherein a groove portion is formed around the outer periphery of the surge tank, a ring member is attached to the groove portion, and the ring member is brought into contact with an inner peripheral surface of the surrounding member. In any one of Claims 1-4 ,
An intake device for an internal combustion engine, wherein the surrounding member is formed such that one end of a cylindrical shape is thin and the other end is thick, and the inner diameter of the cylindrical surface is changed continuously or discontinuously. In any one of Claims 1-5 ,
An intake device for an internal combustion engine, wherein the storage member is made of a resin material.

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