JPH094529A - Intake air taking in device for engine - Google Patents

Abstract

PURPOSE: To reduce the intake noise of an engine in an intake air taking in device for a vehicular engine such as an automobile and an electric car or an industrial engine such as a tractor. CONSTITUTION: In this device, a pipe member 28 arranged in parallel to an intake air taking in pipe 20 attached to the intake pipe of an engine is arranged, and a plurality of openings with which variable valves 34 by which the flow- through sectional area of a communicating passage 39 between the intake air takin in pipe 20 and the pipe member 28 are varied are communicated or by which the intake air taking in pipe 20 and the pipe member 28 are communicated with each other is arranged. The structure of this device is such that the variable valves 34 arranged to these openings are sequentially operated according to the rotation of the engine so that the effective length of the pipe member 28 is changed and resonated with an intake noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial engine intake / intake device such as an engine for vehicles such as automobiles and trains, or an industrial engine such as a tractor.

[0002]

2. Description of the Related Art As is well known, the engine produces a low-frequency sound at a low rotation speed, and when the rotation speed increases, an explosion sound is added and a high-frequency noise is generated at a higher rotation speed. Conventionally, various means have been adopted in order to reduce the noise of the vehicle and industrial engines described above. For example, as is well known, there are side branch type and resonator type structures for muffling the truck. .

An example of the resonator type is Japanese Utility Model Laid-Open No. 3-56865. The technique described in the publication is, as shown in FIGS. 3 and 4, a side frame 2 of the truck.
Along the side wall 1 of the cab 3 of the truck mounted in the vehicle, a partition wall 4 extending downward from the vicinity of the upper end thereof is provided in an intake intake pipe 5 made of a hollow cylindrical body provided in the vertical direction.
A passage 6 of the intake air intake pipe 5 communicating with the atmosphere is provided by one of the passages divided by the above, and the intake passage is formed in the other passage 7 divided by the partition wall 4 through communication holes 8 and 9 of small diameter. A resonance chamber composed of closed chambers 10 and 11 communicating with 6 is formed.

An example of the side branch type is Japanese Utility Model Laid-Open No. 3-56686. In the technique described in the publication, as shown in FIG. 5, the intake intake pipe 5 made of a hollow cylindrical body arranged along the side wall 1 of the cab 3 is appropriately lowered from its upper end by a suitable length as shown above. And a lower pipe member 5b formed of a common pipe communicating with the plurality of divided pipes 6a and 7a, and the upper pipe member 5a formed of two divided pipes 6a and 7a connected to each other. One of the split tubes 6a and 7a has an opening 13 at its upper end.
It is formed as a side branch that closes a and 13b to reduce intake noise.

As another conventional example, there is Japanese Unexamined Utility Model Publication No. 3-56867 (not shown). The technique described in the publication is similar to the above-mentioned conventional example in that a hollow cylindrical intake pipe is arranged vertically along the side wall of the cab, and the lower end of the intake pipe is arranged in parallel along the intake pipe. It has a movable pipe closing member which is inserted into the side branch communicated with the inlet pipe and which changes the effective length of the side branch by its displacement, and further drives the pipe closing member according to the rotational speed of the engine. An actuator is provided to reduce intake noise of the engine and muffle noise in the cab.

[0006]

However, the side branch type and the resonator type shown in FIGS. 4 to 5 described above are aimed at the silencing effect only at a certain frequency. That is, as shown in FIG. 4, the communication holes 8 and 9 of the resonance chamber including the closed chambers 10 and 11 of the resonator are provided at a fixed position of the partition wall 4 and are tuned to a certain frequency. Since there is no mechanism for adjusting the respective peak frequencies when the vehicle is running or idling, the effect can be exerted only for removing the constant noise set above.

The length L of the side branch of the side branch type shown in FIG. 5 is fixed.
It is tuned to a certain frequency corresponding to the length L of this side branch, and there is no mechanism to adjust to each peak frequency when the vehicle is running, idle,
Similar to the resonator type, the effect can be exerted only for removing the constant noise set as described above.

Further, in the technique described in Japanese Utility Model Laid-Open No. 3-56867 (not shown), it is necessary to provide a plurality of actuators corresponding to the plurality of pipe closing members, respectively.
Further, various control devices must be provided between the actuator and the engine, which increases the cost and requires man-hours for maintenance and the like. The present invention has been made in view of such a problem, and is arranged in parallel along an intake intake pipe provided in an upper portion of an intake pipe of an engine, at least an upper portion of which is closed and a lower end portion of which is communicated with the intake intake pipe. A pipe member, which is supported by at least one of the intake intake pipe and the pipe member, is provided at the lower end of the pipe member, and is rotated by the intake inflow pressure. A variable valve that changes the flow cross-sectional area of the communication passage, or an opening that is supported by at least one of the intake intake pipe and the pipe member and that communicates the intake intake pipe with the pipe member is provided. A plurality of variable valves are provided from the upstream side to the downstream end, are rotated by the intake inflow pressure, and are configured to sequentially open the openings from the downstream side to the upstream side as the intake inflow pressure increases. Equipped It allows an object to provide an intake intake device for an engine capable of reducing any desired intake noise over the entire region of the high-rotation low rotation of the engine.

[0009]

Therefore, an engine intake intake device of the present invention according to claim 1 is provided with an intake intake pipe connected to an upper part of an intake pipe of the engine and along the intake intake pipe. A pipe member that is provided in parallel and has at least an upper portion closed and a lower end portion that communicates with the intake intake pipe; and a pipe member that is supported by at least one of the intake intake pipe and the pipe member and that is provided at the lower end portion of the pipe member A variable valve that is rotated by an inflow pressure to change the flow cross-sectional area of the communication passage between the intake intake pipe and the pipe member, or is supported by at least one of the intake intake pipe and the pipe member and the intake air described above. A plurality of openings communicating the intake pipe and the pipe member are provided from the upstream side to the downstream end of the intake intake pipe so that the intake pipe is rotated and opened and closed by the intake inflow pressure, and the downstream side is increased as the intake inflow pressure increases. Yo It is characterized by comprising a plurality of variable valve configured to sequentially open the opening to the upstream side.

According to a second aspect of the present invention, there is provided an intake system for an engine according to the first aspect, wherein the variable valve is provided in at least one of the intake pipe and the pipe member. In the normally open direction of the communication passage,
Alternatively, it is characterized in that the variable valve provided in the plurality of openings is always biased in the closing direction and a biasing means formed integrally with or separately from the variable valve is provided.

According to a third aspect of the present invention, in the intake system for an engine of the present invention, in the structure of the first or second aspect, the inside of the intake intake pipe is limited along a substantially longitudinal axis of the intake intake pipe. It is characterized by including a partition wall forming the above-mentioned tube member. According to a fourth aspect of the present invention, in the intake system for an engine of the present invention, in the configuration according to the third aspect, the variable valve having a pressure receiving portion that is provided at a lower end portion of the partition wall and projects into the intake air intake pipe is provided. It is characterized by having done.

According to a fifth aspect of the present invention, there is provided an intake system for intake of an engine according to any one of the first to fourth aspects, wherein the variable valve is attached to a lower end portion of the pipe member. And a plate member which is provided below the variable valve and which forms the communication passage with the lower end of the pipe member. According to a sixth aspect of the present invention, in the intake air intake device for an engine of the first aspect, in the configuration according to any one of the first to fifth aspects, the upper and lower end portions of the pipe member are formed by closed pipes, and the pipe member A communication passage is provided at the lower end to connect the intake air intake pipe and the pipe member.

According to a seventh aspect of the present invention, in the intake system for an engine of the present invention, in the configuration of the third or fourth aspect, the intake system is supported by at least one of the intake pipe and the pipe member. It is characterized in that a plurality of the above-mentioned openings for communicating the intake intake pipe and the pipe member are provided in the partition wall along the upstream to the downstream end of the intake intake pipe. The intake air intake device for an engine of the present invention according to claim 8 is the device according to claim 3,
In the configuration according to any one of 4 and 7, the variable valve having the pressure receiving portion that is provided so as to be capable of opening and closing the opening of the partition wall and projects into the intake intake pipe and receives the intake inflow pressure, and the opening are closed. The urging means for reducing the urging force of the variable valve in the direction toward the downstream side.

According to a ninth aspect of the present invention, in the intake system for an engine according to the second aspect of the present invention, in the structure according to the second aspect, the urging means is formed of resin, metal or the like which is integral with or separate from the variable valve. It is characterized by being composed of members. Claim 10
The intake intake system for an engine according to the present invention described in claim 1,
The configuration described in any one of 2, 5, 6, and 9 is characterized in that the intake intake pipe and the pipe member are separately formed and connected.

According to an eleventh aspect of the present invention, there is provided an intake system for an engine according to any one of the first to ninth aspects, wherein an opening provided in a closed upper portion of the pipe member is provided. And a variable valve that is rotated by the inflow pressure and is normally biased in the closing direction to close the opening, and is configured to open the variable valve by the intake inflow pressure when the engine is rotating at high speed. It is characterized by that.

[0016]

In the intake intake system for an engine according to the present invention as set forth in claim 1, the intake intake pipe connected to the upper part of the intake pipe of the engine and the intake intake pipe arranged along the intake intake pipe are closed at least in the upper part. A pipe member whose lower end is communicated with the intake intake pipe, and a pipe member supported by at least one of the intake intake pipe and the pipe member and provided at the lower end of the pipe member and rotated by the intake inflow pressure. A variable valve that changes the flow cross-sectional area of the communication path between the intake intake pipe and the pipe member, or is supported by at least one of the intake intake pipe and the pipe member, and the intake intake pipe and the pipe member are provided. A plurality of communicating openings are provided from the upstream side to the downstream end of the intake intake pipe so that they can be opened and closed by being rotated by the intake inflow pressure, and the opening from the downstream side to the upstream side can be opened as the intake inflow pressure increases. Sequentially Since a plurality of variable valves configured as described above are provided, it is possible to automatically change the variable valve by following the intake amount based on the intake amount that changes depending on the engine speed. it can.

According to a second aspect of the present invention, there is provided an intake device for an engine according to the present invention, wherein in the variable valve provided in at least one of the intake pipe and the pipe member, the variable valve is provided in a direction in which the communication passage is normally opened. In addition, or because the variable valve provided in the plurality of openings is always urged in the closing direction and the urging means formed integrally with or separately from the variable valve is provided, The variable valve can be operated according to the intake inflow pressure against the biasing means.

According to a third aspect of the present invention, there is provided an intake device for an engine according to the present invention, wherein a partition wall is formed to limit the inside of the intake pipe along a longitudinal axis of the intake pipe to form the pipe member. Since it is provided, since the intake intake pipe and the pipe member can be integrally formed and have substantially the same shape, the effective resonant frequency can be generated. In the intake air intake device for an engine according to the present invention as set forth in claim 4, the variable valve having the pressure receiving portion provided at the lower end of the partition wall and protruding into the intake air intake pipe is provided. The intake flow hits the protruding portion of the engine, and the variable valve is opened / closed by the intake inflow pressure in accordance with the increase in the intake amount, and at any desired plural positions from low rotation to high rotation of the engine. The intake noise can be reduced by resonating with the pipe member.

According to a fifth aspect of the present invention, there is provided the intake device for an engine according to the present invention, wherein the variable valve is attached to the lower end portion of the pipe member, and the lower end of the pipe member is provided below the variable valve. Since it has a plate member that forms the communication passage between the two, it is possible to easily form the resonance chamber,
The flow cross-sectional area of the communication passage can be easily changed by the variable valve.

According to a sixth aspect of the present invention, there is provided an intake system for an engine according to the present invention, wherein the upper and lower ends of the pipe member are closed pipes, and the lower end of the pipe member has the intake pipe and the pipe member. Since a communication passage for communicating with the pipe is provided, it is possible to attach the variable valve for opening and closing the communication passage to the pipe member at any desired plural positions from low rotation to high rotation of the engine. It can resonate.

According to a seventh aspect of the present invention, there is provided an engine intake intake device, which is supported by at least one of the intake intake pipe and the pipe member and communicates the intake intake pipe with the pipe member. Since the plurality of openings are provided in the partition wall from the upstream side to the downstream side of the intake air intake pipe, the effective length of the pipe member can be changed according to the change of the intake air inflow pressure.

According to an eighth aspect of the present invention, there is provided an intake device for an engine according to the present invention, which has the pressure receiving portion which is provided so as to be capable of opening and closing the opening of the partition wall and which projects into the intake pipe and receives the intake inflow pressure. Since the variable valve is provided with the valve and the biasing means for reducing the biasing force of the variable valve in the direction of closing the opening toward the downstream side, it is possible to reduce the start-up of the engine from low. Due to the intake inflow pressure that accompanies the increase in the intake flow rate over rotation and high rotation, the variable valve arranged on the downstream side is opened in this order to the variable valve arranged on the upstream side. The effective length of can be obtained.

In the intake intake device for an engine according to the ninth aspect of the present invention, since the urging means is an elastic member formed integrally with or separately from the variable valve and made of resin, metal or the like, The biasing means can be provided depending on the position where the variable valve is disposed, and the flow cross-sectional area of the communication passage and the effective length of the pipe member can be promptly formed. In the intake air intake device for an engine according to the present invention as set forth in claim 10, since the intake air intake pipe and the pipe member are separately formed and connected,
The locations where the above-mentioned intake intake pipe and the pipe member are arranged can be arbitrarily selected.

In the case where there is a restriction on the above-mentioned installation location, there is a degree of freedom in the above setting. In the intake intake device for an engine according to the present invention as set forth in claim 11, the opening provided in the closed upper part of the pipe member and the intake inflow pressure are caused to rotate and are normally urged in the closing direction. It has a variable valve with an opening closed, and is configured to open the variable valve by intake inflow pressure when the engine is rotating at a high speed. Therefore, when the engine speed is high and the sound is in a noisy region. Since the intake air amount is further increased and the intake air inflow pressure is also increased, the variable valve provided on the upper portion of the pipe member is opened and closed by the increased intake air inflow pressure, so that the intake air amount can be increased.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) First, the first embodiment will be described.
FIG. 1 is an explanatory view schematically showing an intake air intake device of an engine.

This embodiment shows the above-mentioned resonator type used as the above-mentioned intake noise reducing device, and an intake intake device provided on the side wall of a truck cab shown as a conventional example in FIG. 4 will be described. As shown in FIG. 1, an intake air intake pipe 20 connected to an upper portion of an intake air pipe of an engine (not shown) is provided, and a ventilation path 24 in the intake air intake pipe 20 is arranged substantially along the longitudinal axis of the intake air intake pipe 20. A partition wall 30 is provided which forms a tubular member 28 which is bounded along and closed at the top 26.

At the lower end 32 of the partition wall 30, natural rubber,
The variable valve 34 made of a flexible resin such as synthetic resin is provided in the ventilation passage 24.
It is attached so as to protrude so as to close a part of the inside. A pressure receiving portion R for receiving the intake air inflow pressure is formed on the upper surface of the variable valve 34 at the protruding portion. The ventilation path 24 and the pipe member 28 of the intake intake pipe 20 are provided between the pipe member 28 which is provided below the variable valve 34 so as to project from the intake intake pipe 20 and whose lower end is closed. Communication passage 3 that communicates
A plate member 40 forming 9 is arranged.

The variable valve 34 is arranged at the position shown by the solid line in FIG. 1 in which the communication passage 39 is fully opened when the engine is stopped. The disposition positions of the variable valve 34 and the plate member 40 at the time of stopping the engine described above restrict a part of the air passage 24 of the intake intake pipe 20, but have a sufficient margin so as not to affect the operation of the engine. It is provided with.

Since this embodiment is constructed as described above, when the engine is idle, the amount of intake air introduced from the inlet 22 of the intake intake pipe 20 and sucked into the intake pipe of the engine through the air passage 24. Therefore, the intake air inflow pressure acts on the pressure receiving portion R on the back surface of the variable valve 34.
The elastic force of the variable valve 34, which is the urging means D, cannot be overcome, and the position shown by the solid line in FIG. 1 is maintained. The so-called pipe member 28 acts as a resonator, and the intake air of the engine is The intake noise can be reduced by resonating with the low frequency of the noise, and the muffled noise of the truck cab can be effectively reduced.

Further, the vehicle speed of the vehicle is increased, the amount of intake air in the air passage 24 of the intake intake pipe 20 is increased, and the intake inflow pressure acts on the pressure receiving portion R and thus rises to increase the variable valve 34.
The variable valve 34 is operated at the position shown by the chain double-dashed line in FIG. 1 against the elastic force of the engine to reduce the flow cross-sectional area of the communication passage 39. By resonating with noise, it is possible to reduce intake noise as well as muffled noise in the cab and acceleration noise.

Also in the variable valve 34, the thickness of the variable valve 34 is partially changed, the hardness is partially changed, and a thin portion having a hinge action is provided to distribute the flow in several stages according to the intake air amount. By changing the cross-sectional area, it is possible to reduce the intake noise by causing it to resonate with intake noise of several kinds of frequencies. Further, when the engine reaches a region where the engine speed is increased to a higher level and the influence of intake noise is reduced, a variable valve 54 for opening the opening 52 of the upper portion 26 of the pipe member is provided as shown in FIG. When the valve 54 is opened, the amount of intake air can be increased and the intake air corresponding to the acceleration fuel can be supplied, so that the performance of the engine can be improved.

Next, a second embodiment will be described. (Second Embodiment) Substantially the same parts as those in the first embodiment are designated by the same reference numerals, and only different parts will be described. This embodiment shows the side branch type used as the intake noise reducing device as shown in FIG. 2, and this embodiment is provided at the lower end of the partition wall 30 of the first embodiment. The variable valve 34 and the plate member 40 are eliminated, and the lower end of the pipe member 28 is opened.

In the partition wall 30, a plurality of, in this embodiment, two openings 36a, which communicate the above-mentioned air passage 24 and the pipe member 28, are provided from upstream to downstream of the intake intake pipe 20.
36b is provided. The opening 36 of the partition wall 30
The variable valve 42 has rotary blades 42a and 44a, which are pressure-receiving portions R that are provided so as to be openable and closable a and 36b, respectively, and project into the air passage 24 and receive intake air inflow pressure according to the amount of intake air in the air passage 24. , 44 are provided.

Springs 46a, 4 serving as a biasing means D for reducing the biasing force of the variable valves 42, 44 in the direction of closing the openings 36a, 36b toward the downstream side.
6b is attached to the upper portions of the partition walls 30a and 30b. The variable valves 42 and 44 are both closed when the engine is stopped, and resonate with the pipe member 28.
The effective length is L1 shown in FIG. 2, and the effective length at the time of low rotation such as idle rotation of the engine is L2,
Further, the effective length at the time of high rotation is L3.

When the vehicle is running, the variable valve 44 and the variable valve 42 operate in this order as the engine speed rises and the intake amount increases, but when the variable valve 42 moves, the variable valve 44 moves.
Is configured to close. However, it goes without saying that when the variable valve 42 is open, the effective length L3 of the pipe member 28 is determined regardless of the open / closed state of the lower variable valve 44.

Since the present embodiment is constructed as described above, the intake air introduced from the inlet 22 of the intake intake pipe 20 when the engine is started and at a low rotation speed is passed through the air passage 24 and the intake pipe of the engine (not shown). Is supplied to. At this time, the intake flow acts on the rotary blades 42a and 44a of the variable valves 42 and 44. However, since the intake amount is small and the intake inflow pressure is small, the spring 46a remains in the closed state. Against the biasing force of 46b, the variable valve 44 operates from the closed position indicated by the chain double-dashed line in FIG. 2 to the open position indicated by the solid line.

By the opening operation of the variable valve 44, the effective length L2 of the pipe member 20 resonates with the low-frequency intake noise at the time of low rotation, and the intake noise can be reduced. When the vehicle runs, the engine speed rises, and the intake air amount increases, the intake air inflow pressure increases, so that the rotary vanes 42a rotate against the spring 46a and the variable valve 42 moves to the position shown in FIG. The variable valve 42 is opened by operating from the position indicated by the solid line to the position indicated by the chain double-dashed line, and the effective length L3 of the pipe member 28 is formed.

By resonating the high-frequency intake noise of the intake noise at the time of high rotation with the effective length L3 of the pipe member 28, the intake noise can be reduced. The present embodiment has been described for the case where the two variable valves 42 and 44 are provided, but it is effective to provide two or more variable valves 42 and 44 in accordance with the frequency of the intake noise to be reduced according to the characteristics of the engine used. Intake noise can be reduced.

In this embodiment, the variable valves 42 and 44 are made of hard resin or metal.
Although the springs 46a and 46b for urging the springs 2 and 44 to close the openings 36a and 36b are used, when a soft resin variable valve is used, although not shown, the first
Similar to the variable valve of the embodiment, the variable valves 42, 44 are fixed to the upper portions of the partition walls 30a, 30b so that the intake inflow pressure is received by the rotary vanes 42a, 44a so that the variable valves can be opened and closed by the elastic force of the variable valves. May be.

Further, the variable valve 3 of the first and second embodiments described above.
No. 4, 42, 44 are not limited to these, for example, so-called
A butterfly type choke valve may have a rotating shaft pivotally supported on at least one of the intake intake pipe and the pipe member, that is, the variable valve of the communication passage 39 of the first embodiment or the opening 36a of the second embodiment. It is needless to say that the same operational effect as that of the above-mentioned embodiment can be obtained even if it is used for the variable valve of 36b.

Since the rotary shaft of the choke valve is eccentrically attached to the center of the Chuuk valve body as is well known, the choke valve is opened / closed according to the intake inflow pressure. When the choke valve is arranged, the resonance effect is prevented as much as possible when the choke valve is rotated, and when the choke valve is rotated, the choke valve is excessively rotated to prevent the resonance effect. If you install an appropriate stopper so as not to interfere,
Further opening / closing operation can be reliably performed.

Also in the second embodiment, as in the first embodiment, when the engine is in a region where the engine speed is further increased and the influence of intake noise is reduced, the upper portion 2 of the pipe member 28 is reduced.
If a variable valve 54 that opens the opening 52 of 6 is provided, the variable valve 5
When 4 is opened, the amount of intake air can be increased and the intake air corresponding to the acceleration fuel can be supplied, so that the performance of the engine can be improved.

[0043]

As described in detail above, according to the engine intake intake system of the present invention as set forth in claim 1, the intake intake pipe connected to the upper portion of the intake pipe of the engine and the intake intake pipe are connected to the intake intake pipe. A pipe member that is provided alongside each other and has at least an upper portion closed and a lower end portion that communicates with the intake intake pipe; and a pipe member that is supported by at least one of the intake intake pipe and the pipe member and that is provided at the lower end portion of the pipe member. Together with the variable valve that is rotated by the intake inflow pressure to change the flow cross-sectional area of the communication passage between the intake intake pipe and the pipe member, or is supported by at least one of the intake intake pipe and the pipe member and A plurality of openings for communicating the intake intake pipe with the pipe member are provided from the upstream side to the downstream end of the intake intake pipe so that the intake intake pipe is rotated and opened and closed by the intake inflow pressure. Downstream side Since it has a plurality of variable valves configured to sequentially open the openings to the upstream side, the intake amount that changes due to the rotation of the engine is used as a base to follow the intake amount and automatically The variable valve can be changed.

Therefore, the intake noise can be reduced by causing the pipe member to resonate at any desired plurality of positions from low rotation to high rotation of the engine. According to the intake air intake device for an engine of the present invention as set forth in claim 2,
In the configuration described above, in a variable valve provided in at least one of the intake intake pipe and the pipe member, the variable valve is provided in the normally opening direction of the communication passage or in the plurality of openings provided in the plurality of openings. Since the valve is always biased in the closing direction and the biasing means is formed integrally with or separately from the variable valve, the variable valve is acted against by the intake inflow pressure against the biasing means. It can be activated depending on the inflow pressure.

Therefore, the intake noise can be reduced by causing the pipe member to resonate at any desired plural positions from low rotation to high rotation of the engine. Further, the operation of the variable valve does not require a specially provided actuator for operating the variable valve as in the conventional example described above, and the variable valve can be operated only by the intake air inflow pressure as described above. It is inexpensive, the structure is simple, and it can be made compact.

According to the intake air intake device for an engine of the present invention as defined in claim 3, in the structure of claim 1 or 2,
Since the inside of the intake intake pipe is provided with a partition wall that limits the inside of the intake intake pipe along a substantially longitudinal axis of the intake intake pipe to form the pipe member, the intake intake pipe and the pipe member are integrally structured and have substantially the same shape. Therefore, the above-mentioned resonant frequency can be effectively generated.

Therefore, the intake noise can be accurately reduced, and the intake noise can be reduced by causing the pipe member to resonate at any desired plural positions from low rotation to high rotation of the engine. According to a fourth aspect of the present invention, in the intake system for an engine of the present invention, in the configuration according to the third aspect, the variable valve has a pressure receiving portion that is provided at a lower end portion of the partition wall and projects into the intake air intake pipe. Since, the intake flow hits the protruding portion of the variable valve,
The variable valve is opened / closed by the intake inflow pressure in accordance with the increase of the intake amount, and the intake noise is reduced by resonating with the pipe member at any desired plural positions from low rotation to high rotation of the engine. can do.

Therefore, the intake noise can be accurately reduced, and the intake noise can be reduced by causing the pipe member to resonate at any desired plural positions from the low rotation to the high rotation of the engine. According to the intake intake device for an engine of the present invention described in claim 5, in the configuration according to any one of claims 1 to 4, the variable valve attached to the lower end portion of the pipe member, Since the plate member is provided below the variable valve and forms the communication passage between the lower end of the pipe member and the lower end of the pipe member, the resonance chamber can be easily formed. The distribution cross-sectional area can be easily changed.

According to the sixth aspect of the present invention, there is provided the intake system for an engine according to the first aspect, wherein the upper and lower ends of the pipe member are closed pipes. Since the lower end of the pipe member is provided with a communication passage that communicates the intake intake pipe with the pipe member, it is possible to increase the engine speed from low rotation to high by simply attaching the variable valve that opens and closes the communication passage. The pipe member can be made to resonate at any desired plural positions throughout the rotation, and the intake noise can be reduced.

According to the intake air intake device for an engine of the present invention as defined in claim 7, in the structure as defined in claim 3 or 4,
A plurality of the openings, which are supported by at least one of the intake intake pipe and the pipe member and communicate the intake intake pipe and the pipe member, are provided in the partition wall from the upstream side to the downstream end of the intake intake pipe. Since the individual pieces are provided, the effective length of the pipe member can be changed according to the change of the intake air inflow pressure.

Therefore, the intake noise can be accurately reduced, and the intake noise can be reduced by causing the pipe member to resonate with the pipe member at any desired plural positions from low rotation to high rotation of the engine. According to the intake intake device for an engine of the present invention described in claim 8, in the structure according to any one of claims 3, 4 and 7, the opening of the partition wall is provided so as to be openable and closable, respectively. The variable valve having a pressure receiving portion that projects into the pipe and receives the intake inflow pressure; and the urging means that reduces the urging force of the variable valve in the direction of closing the opening toward the downstream side. Since it is equipped with a variable valve, low rotation from the start of the engine,
Due to the intake inflow pressure that accompanies the increase in the intake flow rate over high rotation, the variable valve arranged on the downstream side is sequentially opened to the variable valve arranged on the upstream side. Moreover, the effective length of the pipe member can be obtained.

Therefore, the intake noise can be accurately reduced, and the intake noise can be reduced by causing the pipe member to resonate with the pipe member at any desired plural positions from low rotation to high rotation of the engine. According to the engine intake air intake device of the present invention described in claim 9, in the configuration of claim 2, the biasing means is a resin which is integral with or separate from the variable valve,
Since the elastic member is made of metal or the like, the urging means can be provided according to the position of the variable valve, and the flow cross-sectional area of the communication passage and the effective length of the pipe member can be controlled. Can be changed promptly.

Therefore, the intake noise can be properly reduced, and the intake noise can be reduced by causing the pipe member to resonate at any desired plural positions from low rotation to high rotation of the engine. According to the engine intake air intake device of the present invention as defined in claim 10, claims 1, 2, 5, 6, are provided.
9. In the configuration according to any one of 9 above, since the intake intake pipe and the pipe member are separately formed and connected, the place where the intake intake pipe and the pipe member are arranged can be arbitrarily selected. In addition, the shape of the tube member can be set arbitrarily, so that a resonance effect can be obtained as needed.

When there is a restriction on the place of installation, there is a degree of freedom in the above settings. According to the intake air intake device for an engine of the present invention described in claim 11, in the configuration according to any one of claims 1 to 9, the opening provided in the closed upper portion of the pipe member and the intake air inflow. It has a variable valve that is rotated by pressure and is normally urged in the closing direction to close the opening, and is configured to open the variable valve by intake inflow pressure when the engine is rotating at high speed. In the region where the engine speed becomes high and the noise is not annoying, the intake amount further increases and the intake inflow pressure also increases. Therefore, the variable valve provided above the pipe member increases. It is opened and closed by the intake inflow pressure, and the intake air is introduced from both the intake intake pipe and the pipe member, so that the performance of the engine can be improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view schematically showing an intake air intake device for an engine according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view schematically showing an intake air intake device for an engine according to a second embodiment of the present invention.

FIG. 3 is a schematic side view of a cab of a truck equipped with a conventional engine intake intake device.

FIG. 4 is a schematic vertical section taken along line 4A-4A in FIG.
Explanatory diagram.

FIG. 5 is a schematic vertical sectional view similar to FIG. 4 showing another conventional example.

[Explanation of symbols]

 20 intake air intake pipe 22 inlet 24 air passage 26 upper 28 pipe member 30 partition wall 30a partition wall 30b partition wall 32 lower end portion 34 variable valve 36a opening 36b opening 39 communication passage 40 plate member 42 variable valve 44 variable valve 42a rotary blade (pressure receiving portion R) 44a rotary blade (pressure receiving part R) 46a spring 46b spring 52 opening 54 variable valve D biasing means R pressure receiving part

Claims (11)

[Claims] 1. An intake air intake pipe connected to an upper portion of an intake air pipe of an engine; and a pipe member arranged along the intake air intake pipe in parallel, at least an upper portion of which is closed, and a lower end portion of which is connected to the intake air intake pipe. A flow cross-sectional area of the communication passage between the intake intake pipe and the pipe member, which is supported by at least one of the intake intake pipe and the pipe member, is provided at the lower end of the pipe member, and is rotated by the intake inflow pressure. Or a variable valve for changing the intake air intake pipe and an opening that is supported by at least one of the intake air intake pipe and the pipe member and connects the intake air intake pipe and the pipe member to each other from an upstream side to a downstream end of the intake air intake pipe. A plurality of variable valves are provided, which are opened and closed by being rotated by the intake inflow pressure, and which are configured to sequentially open the opening from the downstream side to the upstream side as the intake inflow pressure increases. To The symptoms, intake intake device for an engine. 2. A variable valve provided in at least one of the intake intake pipe and the pipe member, wherein the variable valve is provided in the normally open direction of the communication passage or in the plurality of openings. The intake device for an engine according to claim 1, further comprising a biasing means that is always biased in the closing direction and is integrally or separately provided with the variable valve. 3. The partition wall according to claim 1, further comprising a partition wall which forms the pipe member by limiting the inside of the intake air intake pipe along a substantially longitudinal axis of the intake air intake pipe. Engine intake intake device. 4. The intake device for an engine according to claim 3, further comprising: the variable valve having a pressure receiving portion provided at a lower end portion of the partition wall and protruding into the intake intake pipe. 5. A variable valve attached to a lower end portion of the pipe member, and a plate member provided below the variable valve and forming the communication passage between the variable valve and the lower end of the pipe member. The intake intake device for an engine according to any one of claims 1 to 4, characterized in that. 6. A communication passage that connects the intake intake pipe and the pipe member is provided at a lower end portion of the pipe member, the closed pipe having upper and lower ends of the pipe member closed. The intake air intake device for an engine according to any one of claims 1 to 5. 7. The opening, which is supported by at least one of the intake intake pipe and the pipe member and communicates the intake intake pipe with the pipe member, extends from the upstream side to the downstream end of the intake intake pipe. The intake air intake device for an engine according to claim 3 or 4, wherein a plurality of them are provided on the partition wall. 8. A variable valve having a pressure receiving portion which is provided to open and close each opening of the partition wall and projects into the intake intake pipe to receive the intake inflow pressure; and a variable valve for closing the opening. The intake device for an engine according to any one of claims 3, 4 and 7, further comprising: the urging means that reduces the urging force toward the downstream side. 9. The intake intake system for an engine according to claim 2, wherein said urging means is made of an elastic member formed integrally with or separately from said variable valve and made of resin, metal or the like. 10. The intake air for an engine according to claim 1, wherein the intake intake pipe and the pipe member are separately formed and are connected to each other. Intake device. 11. An opening provided in the closed upper portion of the pipe member, and a variable valve which is rotated by intake air inflow pressure and is normally biased in the closing direction to close the opening. A variable valve is opened by intake air inflow pressure when the engine is rotating at high speed,
An engine intake intake device according to any one of claims 1 to 9.