JPH07217511A - Synthetic resin blow-molded duct for automobile engine air intake - Google Patents

Abstract

PURPOSE:To reduce the deformation of both a duct and a resonator so as to obtain the duct durable and withstanding even under long-term use and dispense with the connecting work of the duct and resonator prior to use by eliminating a joint between the duct and the resonator, and connecting the duct and the resonator integrally in the state of making up each other. CONSTITUTION:A curved blow-molded duct 10 is formed of a soft part and a hard part. A part of the soft part 10b is formed into a bellows part 14. At least one resonator 11 is integrally formed along the outside of the partial side face fo the hard part 10a by a single parison made of thermoplastic synthetic resin. The duct 10 and the resonator 11 are communicated with each other in the ventilated state by a partial communicating part 12. As a result, the duct 10 and the resonator 11 are integrally connected in the state of making up each other so as to reduce the deformation of both, thereby obtaining the duct 10 durable and withstanding even under long-term use and dispensing with the connecting work of the duct 10 and resonator 11 heretofore necessary prior to use.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile engine intake duct formed by blow molding of thermoplastic synthetic resin.

[0002]

2. Description of the Related Art In an air intake duct of an automobile engine, each time air or air and fuel gas are taken into a cylinder of the engine, the pressure of the air is drastically changed and a vibration noise is generated. Friction between the airflow and the ducts also makes noise, which is unpleasant not only for those who drive the vehicle but also for other passengers, as well as for passers-by outside the vehicle and residents along the road.

On the other hand, since the engine room is exposed to high temperature and violent vibration, a tortuous duct having a hard portion and a soft portion is disclosed in Japanese Unexamined Patent Publication No. 4-1895.
It is known from Figures 28 and 28c of publication 28.

Further, a hollow body having one opening is separately molded in advance, and the hollow body is inserted into a blow mold so that the opening contacts the parison guided in the blow mold. , The parison is blown in a blow molding die to bring the previously molded hollow body and the blow molding part into close contact with each other, and at the opening, the parison is ruptured by the air pressure in the parison to blow the hollow body and the former hollow body. A method of communicating with a hollow body by molding through the opening and a method manufactured by this method are described in the claims of Japanese Patent Publication No. 3-24329 and column 3, line 35 to column 4, line 17. Have been described.

In the prior art described in this publication, when the insert hollow body is large, it may be crushed by the heat and air pressure received during blow molding, and the rupture of the plow wall at the opening does not have a uniform shape. Or, it is difficult to expect to obtain a molded product having a constant shape as a whole, and the molding is performed in two steps, which increases the molding cost.

Further, holes are formed in the preformed pipe in the radial direction, a parison is supplied to the outside of the hollow pipe, the blow mold is closed from the outside of the hollow pipe and the parison, and pressurized air is introduced from the inside of the hollow pipe. From the radial holes,
A method of blowing into the parison on the outside of the hollow pipe to form the hollow chamber having the holes connected to the outside of the hollow pipe is disclosed in Japanese Patent Publication No.
No. 3, column 3, line 8 to column 6, line 14 and the drawings are described in detail. However, this molding is also a two-step process, and it is difficult to supply the parison to the outside of the meandering duct, and it is limited to the linear shape.

However, in a duct used in an engine room, where the bellows portion is soft and has no burr, the duct 10 is provided as shown in FIGS. 7 to 9 for the purpose of generating or absorbing the noise. Resonator 1 separately from
A resonance box referred to as No. 1 is molded by a blow molding method, and this is connected to a duct 10 made of the blow molded product via a rubber tube 1, a seam thereof is welded, or fixed with screws or tacks 2. And is using it. Alternatively, as shown in FIG. 10, a straight pipe having a short rigid duct and a resonator are integrally formed by blow molding, and a curved pipe and a bellows pipe are connected to the front and rear of the blow pipe, which is also found in the market.

However, joining many parts as described above is not only a great labor, but also the duct 1
0 means that the pressure change is repeated and the high-speed air flow passes through the inside, so that the load repeatedly applied causes rattling in the screwed or tacked portion 1 and the fitting portion, and air leaks from this portion. Alternatively, if the joining is insufficient, there is a possibility that it may become a source of generating a severe friction noise due to air leakage.

[0009]

SUMMARY OF THE INVENTION Therefore, according to the present invention, a series of ducts are composed of a hard portion and a soft portion, and meander, and a part of the bellows portion is formed at least in the soft portion. In addition, in the case where there is no burr in the bellows part during blow molding, the duct and the resonator are joined together to eliminate the seam between the duct and the resonator during molding, and without impairing the intake performance of the duct. The deformation is reduced, especially the resonator part is durable so that it does not deform due to changes in atmospheric pressure, and it can withstand long-term use, eliminating the need to connect ducts and resonators prior to use. It is a common purpose of each claim.

A further object peculiar to the invention of claim 3 is that a duct having a complicated curved shape or a curved shape is molded by a single parison as described above. It is to absorb the noise of the resonance at the same time.

The object of the present invention according to claim 4 is that the part inserted in a part of the duct is firmly connected to the duct, and the insert part and the duct of the part to which the part is attached are made of different materials. Also provides the market with a blow-molded duct in which these are firmly bonded during duct molding. Another specific object of the invention according to claim 6 is to provide a blow molded product to the market in which a hard pipe-shaped insert part is connected to a part of a soft part of a duct.

[0012]

In order to solve the above-mentioned problems, according to the present invention, the duct is formed by a single parison consisting of a hard part and a soft part, and is curved or bent. , A part of the soft part in which a bellows-free bellows part is formed, and at least one resonator is provided by the duct and a single parison along the outside of a part of the side surface of the hard part of the duct. A blow molding duct made of synthetic resin for intake of an automobile engine, characterized in that the duct and the resonator are integrally formed so that the duct and the resonator are communicable only in a part of the communicating portion.

In order to solve the above-mentioned problems, the duct and the resonator of the synthetic resin blow molding duct for automobile engine intake of the present invention are integrally formed by a connecting wall formed in a part of the parison in the axial direction of the duct. It is preferable that it is characterized by

In order to solve the above problems, the resonator of the blow molding duct made of synthetic resin for automobile engine intake according to the present invention is different in volume and diameter of a communicating portion between the ducts. In some cases, it is characterized in that three to three are provided.

In order to solve the above-mentioned problems, insert parts are integrally joined to a part of the blow molding duct made of synthetic resin for automobile engine intake of the present invention at the time of blow molding of this duct. The insert part is formed by injection-molding a thin disk collar-shaped connecting base made of the same material as that of the duct mounting part on the base, and the connecting base is integrated with the duct during the blow molding. Is preferable.

In order to solve the above-mentioned problems, the other portion of the insert part of the blow molding duct made of synthetic resin for intake of an automobile engine of the present invention has a pipe shape with a small diameter, and the hollow hole is in the duct. In some cases, it is characterized by being in communication with.

In order to solve the above-mentioned problems, the duct of the insert part mounting portion of the blow molding duct made of synthetic resin for automobile engine intake of the present invention and the joint base of the insert part are both made of a soft thermoplastic synthetic resin, In some cases, the same type of resin is used, and the other part of the insert part is a hard synthetic resin molded product.

In this specification, the hard resin and the soft resin are relative expressions, not absolute expressions.
Hard resin has a tensile or flexural modulus of about 45.
00kgf / cm refers to ^two or more things, the soft resin is the elastic modulus refers to those 2000 to 5000 kgf / cm ^2, there is no limiting sense to this number itself.

[0019]

With respect to the specified invention according to claim 1 of the present invention,
To use this, it is usually used by connecting it to the intake manifold and the air cleaner or the upstream side of the air cleaner. In this way, when the engine is operated, the air flow passes through the duct of the present invention while repeatedly changing the atmospheric pressure according to the intermittent intake of the engine.

At this time, the air flow propagates a friction noise due to friction with the inner surface of the duct, a vibration noise of the duct due to repetition of the above-mentioned unevenness of atmospheric pressure, and an impact noise caused by opening and closing the intake and exhaust valves of the engine. Although generated, the change in atmospheric pressure in the duct propagates as it is into the resonator through the ventilation portion, and a part of the noise is resonantly absorbed, thereby significantly reducing the noise. Since the resonator has no opening other than the ventilation part, no air is sucked in from the outside.

Since the duct has a bellows-shaped bellows portion made of a soft portion, one end of the duct is fixed to the engine side and the other end is fixed to the vehicle body side. Vibrations are absorbed by the bellows, and stress concentration does not occur at the both end mounting portions. Further, since the duct and the resonator are not fitted, welded, or connected to each other by screws or tacks, there is no risk of air leakage from the connected part even by the above-mentioned vibration.

Further, since there is no burr on the entire length of the duct and the resonator as a whole, there is no weak portion in the entire circumference of the duct, and the entire duct has the function of withstanding the above-mentioned atmospheric pressure change. Further, as described above, since the duct and the resonator are a single member, it is only necessary to connect the duct when assembling to the automobile, and the parts production and inventory management are facilitated.

According to a second aspect of the present invention, the duct and the resonator are integrated on both sides of the air-permeable communicating portion with a connecting wall formed by a part of a parison forming the duct and the resonator. Since it is characterized, it does not separate even if there is vibration due to the above-mentioned gas flow, air pressure density, vibration due to running of the car, and since the connecting part is formed by the connecting wall, the connecting part by vibration vibrates. There is no effect of forming holes.

According to a third aspect of the present invention, the number of the resonators provided in the duct is different from that of the volume of the resonator and the diameter of the communicating portion with the duct. Therefore, it has the function of simultaneously absorbing noises of several frequencies corresponding to the volume of each resonator and the diameter of the communicating portion.

In the invention according to claim 4, the insert part is, as described above, a thin disk brim-shaped connecting base made of the same material as that of the duct mounting part, which is integrally connected to the base part by injection molding. Since the connection base portion is integrated with the duct at the time of the blow molding, the connection between the connection base portion and the duct is strong.

In the invention according to claim 5, the other part of the insert part is in the shape of a pipe having a small diameter, and the hollow hole communicates with the inside of the duct. It is used by fitting various measurement sensors, hoses, etc. to the hype-shaped part of the part.

In the invention according to claim 6, even if the duct is a soft portion, since the portion other than the connection base of the insert part is hard, it is sufficient even when the sensor, hose, etc. are fitted. Retains supporting power. Further, the connecting force between the insert part and the duct is firmly integrated.

[0028]

【Example】

Embodiment 1 It is an embodiment shown in FIGS. 1 to 3 and including the inventions of claims 1 and 2, and claims 4 to 6. Reference numeral 10 denotes a duct made of a blow molded product, and a part of the duct 10 and a parison forming the duct are integrally formed with a resonator (silence box) 11 which is integrally formed at the time of blow molding. Is the communication part 12
The duct 10 and the resonator 11 other than the communicating portion 12 are integrated by a connecting wall 13 extending in the axial direction of the duct 10 formed by closely contacting the parison. Therefore, the resonator 11 is the duct 1
It is formed along part of 0.

A bellows portion 14 is formed in the portion of the duct 10 without the resonator 11. The duct 10 is composed of two layers of a hard resin and a soft resin (resin having elasticity). The portion integrated with the above-mentioned resonator 11 is the hard portion 10a in the thick portion of the hard layer and the bellows 13 portion. The vicinity of one end of the duct is a soft portion 10b whose thickness is formed of a soft layer. These ducts 10 and resonators 11 do not have burrs formed by cutting through with a mold during blowing.

In the above description, the hard portion 10a and the soft portion 10
Although b is shown as having two layers, the hard part 10a and the soft part 10b are formed by a single parison in a continuous manner in the axial direction, respectively. include.

Numeral 15 is an insert part consisting of a soft pipe 16 provided in the hard portion 10a of the duct 10 (see FIG. 5), and the connecting base 17 at the base of the soft pipe 16 is the duct 1
The same hard thermoplastic synthetic resin as that of No. 0, the same materials are integrated by injection molding, and the joint base 17 is a thin disk flange-shaped joint base. 17 is integrated with the duct hard portion 10a.

The soft pipe 16 and the connection base 17 are mechanically and firmly connected to each other due to the unevenness of the boundary surface rather than welding (see FIG. 5). Reference numeral 18 is a hard insert part provided in the soft portion 10b of the duct 10, and the joint base 20 of the base portion of the hard pipe 19 is the same soft thermoplastic synthetic resin as that of the duct 10 of that portion, and the same material is injected. The integrated base 2 is formed by molding and is integrated.
Reference numeral 0 denotes a thin disk brim shape, and this thin disk brim-shaped coupling base 20 is integrated with the duct soft portion 10b (see FIG. 6).

As described above with reference to FIG. 6, the hard pipe 19 and the soft joint base 20 are joined together as shown in FIG.
A plurality of grooves 21 in the circumferential direction and through holes 22 penetrating the hard pipe 19 in the radial direction are provided on the outer side of the groove 21.
And a part of the coupling base 20 is injection-molded into the through hole 22 to firmly and integrally form it.

Embodiment 2 As shown in FIGS. 4 and 5, this is an embodiment including the invention of claims 3 to 6. The parts having the same reference numerals as those in the first embodiment are the same as those in the first embodiment. The difference is that the two resonators 11a and 11b are provided, and the diameter of the communicating portion 12 and the volume of the resonator are different from each other. The volume and the diameter of the communicating portion 12 correspond to the frequency of the noise to be absorbed most. It is molded. The other structure is substantially the same as that of the first embodiment.

Polypropylene, for example, is used as the hard resin having a tensile or flexural modulus of about 6000 to 7,000 kgf / cm ² in each of the above-mentioned embodiments, and the polypropylene is an elastomer resin (for example, AES Japan stock) as the soft resin. Santoprene (registered trademark of the company) was mixed and the same elastic modulus of about 3000 kgf / cm ² was used. The soft material and the hard material are not limited to the above-mentioned materials, and other thermoplastic resins such as polyethylene and polyamide are naturally included in the embodiments of the present invention as long as they are resins of the same series or compatible with each other.

Operation of the Embodiments In the devices of these embodiments, the opening of the hard portion 10a is usually on the upstream side, and the opening of the soft portion 10b is on the downstream side. Used by connecting with members. Corresponding sensors and other parts are connected to the soft pipe 16 and the hard pipe 18. If you do this Each sensor projects into the duct 10.

When the automobile engine is operated, the air flows violently in these ducts as the engine operates, and the air flowing inside the duct as the intake valve of each engine opens and closes. The atmospheric pressure pulsates, and the opening / closing sound of the intake valve propagates to the internal air flow.

The vibration of the change in the atmospheric pressure of the air, which is such a noise source, propagates into the resonator 11 through the ventilation portion 13 and is resonantly absorbed therein. In the second embodiment, two types of resonators 11a and 11b are provided, so that noises of two types of cycles are resonantly absorbed. If there are three or more resonators, the noise of the corresponding frequency will be absorbed.

In this case, the resonator 11 (11a,
(Including 11b) is formed in the hard portion of the duct 10 and therefore does not deform even by the above-mentioned resonance vibration. When attached to the insert part 15 or 18 of the duct, the tip of each sensor is in a state of protruding into the duct 10,
Information corresponding to the purpose, such as temperature and atmospheric pressure, is detected.

At the portion where the hard pipe 19 is connected to the soft portion 10b of the duct 10 through the soft connecting base 20, the twisting force and the bending force are applied when the sensor device is attached to the hard pipe 19 portion. Is applied to the hard pipe portion, the soft base 20 and the soft portion 10b of the duct 10 in the vicinity thereof are both deformed, and stress concentration does not occur in a part.

In the portion where the soft pipe 16 is connected to the hard portion 10a of the duct 10 through the hard connection board 17, when the equipment mounting portion is inserted into the soft pipe 16 portion, the soft pipe 16 is inserted. Is easily deformed, and when a bending force is applied to the instrument after installation, the soft pipe 1
Only the 6 parts are inclined.

[0042]

According to the first aspect of the present invention, the friction noise due to the friction between the inner surface of the duct and the air flow, the vibration noise of the duct due to the repetition of the unevenness of the atmospheric pressure, and the impact noise due to the opening and closing of the intake and exhaust valves of the engine propagate. And these sounds are generated,
The change in atmospheric pressure in the duct propagates into the resonator as it is, and a part of the noise is absorbed by resonance, which has the effect of significantly reducing the noise. Among the ducts, the resonator is
Since it is characterized in that it is molded into a hard portion, there is no possibility of causing new vibration during resonance absorption.

A bellows portion is formed in a part of the duct, and the bellows portion is soft. Therefore, when this bellows portion is assembled to other parts, this part is once contracted and both ends are fitted to the other parts. Be combined. Even after the assembling, the bellows portion has an effect to disperse and absorb the external force even when the attachment portions at both ends of the duct vibrate separately.

In addition, since there is no burr in the entire length and the entire circumference of the duct, there is no fragile portion, and there is no risk of the duct rupturing or cracking in the axial direction or the circumferential direction even when the atmospheric pressure changes drastically.

According to the second aspect of the invention, since it is constructed and operates as described above, in addition to the effect of the first aspect of the invention, it is possible to use the above-mentioned vibration due to the air flow, the density of the atmospheric pressure, and the running of the automobile. Even if there is accompanying vibration, the duct and the resonator are firmly integrated with each other by the connecting wall 13, and there is no connection by screws or tacks at all, so there is no separation, and vibration causes a hole in the connecting portion. There is no fear that

According to a third aspect of the present invention, the number of the resonators having different volumes and the diameters of the communicating portions with the ducts is different, and the number of the resonators is two or three. Therefore, it has an effect of simultaneously absorbing noise of several kinds of frequencies corresponding to the volume of each resonator and the diameter of the communicating portion.

According to the fourth aspect of the present invention, the insert part is, as described above, a thin disk collar-shaped connecting base made of the same material as that of the duct mounting part, which is connected to the base by injection molding. Since the base part is integrated with the duct at the time of the blow molding, the bond between the base plate and the duct is firmly melt-bonded and they are not separated during use. .

According to a fifth aspect of the present invention, the other part of the insert part has a pipe shape with a small diameter, and the hollow hole communicates with the inside of the duct. If various measuring sensors are inserted into the pipe-shaped part of the component, the tip of the sensor can easily be projected into the duct, and the state inside the duct can be detected. It is also possible to fit a hose or the like to connect to another device.

According to the sixth aspect of the present invention, even if the duct is a soft portion, the insert part is hard, so that even when the sensor, the hose, etc. are fitted,
Holds sufficient supporting force. Also, the connecting force between the insert part and the duct is firmly integrated.

Further, even if a twisting force when connecting these connected devices or hoses or the like and the duct parts and these devices after mounting vibrate separately, since the connection base of the insert parts is soft, The bond is not only strong, but stress is not concentrated on a part of the bond, and there is no risk that the bond base part will separate from the duct.

Effects Unique to the Embodiments In the first embodiment, the effects of the inventions described in all the other claims are combined with the effect of the invention described in the third embodiment. In the second embodiment, the effects of all the claimed inventions are also obtained.

Others In the above-mentioned two embodiments, particularly the connection base 20 of the insert part and the other hard pipe 1
The rigid pipe 19 is coupled to the rigid pipe 19 by welding and mechanical coupling by several grooves 21 formed on the outer peripheral surface of the rigid pipe 19 and through holes 22 penetrating in the radial direction. With respect to the twisting force, the coupling force of the through hole 22 in the radial direction is sufficiently endured, and with respect to the pulling force, the coupling of the several grooves 21 and the through hole 22 and the coupling of the through hole 22 with each other. Upon joining, the hard pipe 19 and the joining base 20 are not separated from each other, and the joining base 20 and the duct portion to which this is joined are both of the same type of soft synthetic resin, and are inserted during blow molding, Since they are welded to each other, they are completely welded and integrated, and since they are both soft, stress is not concentrated on a part of the external force applied to the hard pipe 19 as described above, and the connection base 2
0 does not separate from the duct 10.

In the above two embodiments, the duct 1
Even in the case where it is connected to the hard portion 10a of 0 through the hard connecting board 17 which is connected to the soft pipe 16, the connection is strong as described above, and the soft pipe portion has a lightweight sensor or the like. If the device is inserted as it is, it is bound and supported by the soft pipe 16 portion. Alternatively, a simple band can be used to bind and secure from the outside of the soft pipe.

[Brief description of drawings]

FIG. 1 is a side view of a first embodiment.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a side view of the second embodiment.

FIG. 5 is a cross-sectional view of the insert part before being joined to the duct.

FIG. 6 is a cross-sectional view of another insert component before being joined to the duct.

FIG. 7 is a cross-sectional view showing a connected state of a duct and a resonator of a prior art.

FIG. 8 is a cross-sectional view of another prior art.

FIG. 9 is a cross-sectional view of yet another prior art.

FIG. 10 is a partially cutaway side view of another prior art.

[Simple explanation of symbols]

 10 Duct 11 Resonator 12 Communication part 13 Connection wall 14 Bellows part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location // B29K 105: 20 B29L 31:30

Claims (6)

[Claims] 1. A duct is molded from a single parison composed of a hard portion and a soft portion, and is curved or bent, and a burr-free bellows portion is formed in a part of the soft portion. At least one resonator is integrally formed by the duct and a single parison along the outer side of a part of the hard portion of the duct, and the duct and the resonator partially communicate with each other. A blow molded duct made of synthetic resin for automobile engine intake, characterized in that it is ventilated only in the section. 2. The blower made of synthetic resin for automobile engine intake according to claim 1, wherein the duct and the resonator are integrated by a connecting wall formed in a part of a parison in the axial direction of the duct. Molded duct. 3. The resonator according to claim 1 or 2, wherein two or three resonators having different volumes and diameters of communicating portions with the duct are provided for one duct. Blow molding duct made of synthetic resin for automobile engine intake. 4. An insert part is integrally connected to a part of the duct during blow molding of the duct, and the insert part has a thin disk flanged shape made of the same material as that of the attachment part of the duct at a base part thereof. 4. The connection base according to claim 1 is connected by injection molding, and the connection base is integrated with the duct during the blow molding. Blow molding duct made of synthetic resin for automobile engine intake. 5. The method according to claim 3, wherein the other portion of the insert part has a pipe shape with a small diameter, and the hollow hole communicates with the inside of the duct.
A blow molding duct made of synthetic resin for intake of an automobile engine as described. 6. The duct of the insert part mounting portion and the joint base of the insert part are both soft thermoplastic synthetic resin and the same type of resin, and the other part of the insert part is a hard synthetic resin molded product. A blow molding duct made of synthetic resin for automobile engine intake according to claim 4, characterized in that.