CN114135725A

CN114135725A - Corrugated pipe for vehicle

Info

Publication number: CN114135725A
Application number: CN202010923826.0A
Authority: CN
Inventors: 邹斌; 谢荣
Original assignee: Mahle Automobile Technology China Co ltd
Current assignee: Mahle Automobile Technology China Co ltd
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2022-03-04

Abstract

The utility model provides an automobile-used bellows, the bellows is equipped with the ripple section, the ripple section is provided with a plurality of wave form parts that connect gradually, thereby have a plurality of crests and trough, when the bellows is in natural state, through setting up the wave height of wave form part at first high range, the crest angle sets up at first angle scope, the wall thickness of ripple section sets up at first thickness scope, when the bellows adopts the mode integrated into one piece of the thermoplastic elastomer of moulding plastics, realize that the bellows is easy drawing of patterns at injection moulding's in-process, and make the bellows possess better collapse resistance ability and motion compensation ability, produce the bellows through this injection moulding process, the shortcoming of using bellows blow molding production has been avoided, and overcome rubber injection molding process complicacy, the shortcoming of raw and other materials with high costs, production efficiency is improved.

Description

Corrugated pipe for vehicle

Technical Field

The disclosure relates to engine accessories, in particular to a vehicle corrugated pipe.

Background

The air outlet pipe of an air filter of an air inlet system of an automobile engine is generally a corrugated pipe, and the existing corrugated pipe comprises the following two types:

the first is a bellows formed by blow molding a TPV (thermoplastic vulcanizate) material, which has high molding cost due to a large amount of excess material during molding, poor durability, poor dimensional accuracy and sealing properties, is easily collapsed when subjected to negative pressure, and has poor motion compensation capability.

The second is a corrugated pipe formed by processing rubber (thermosetting material) such as vulcanized rubber through an injection process, the rubber is formed through a complicated process such as coking, and the forming process is difficult to control, so that the wall thickness and the wave pitch of the corrugated section of the whole product are large, the raw material cost is high, the production efficiency is low, and the rubber belongs to the thermosetting material and can not be injection molded.

Disclosure of Invention

The present disclosure is made in view of the state of the art described above. An object of the present disclosure is to provide a corrugated pipe for a vehicle, which is simple to manufacture, low in cost, light in weight, has excellent motion compensation performance and durability, and is not easily collapsed when subjected to negative pressure.

A corrugated pipe for a vehicle is provided with a corrugated section and a connecting section, wherein the connecting section is provided with a clamp connection part, and the inner surface of the clamp connection part is provided with an annular sealing rib; thereby the ripple section sets up to a plurality of wave form portions that connect gradually and has a plurality of crests and a plurality of trough, the crest with the difference in height of trough is the wave height, adjacent two the crest or adjacent two the distance between the trough is the wave distance, the bellows adopts the whole injection moulding of thermoplastic elastomer, the wave height is 5mm to 15mm, the wave distance is 6mm to 11 mm.

Preferably, the wall thickness of the corrugated section is 0.5mm to 1.5 mm.

Preferably, the wave section has a form of a triangular wave, and the surfaces of two adjacent sides of each of the peaks of the wave section intersect to form a peak angle, and the peak angle is 10 ° to 60 °.

Preferably, the corrugated pipe is further provided with a turning section, the turning section turns relative to the corrugated section, the connecting section is positioned at two ends of the whole formed by the turning section and the corrugated section, the wall thickness of the turning section is greater than that of the corrugated section, and/or the wall thickness of the connecting section is greater than that of the corrugated section.

Preferably, the wall thickness of the turning section is 1.2mm to 4mm, and/or the wall thickness of the connecting section is 1.2mm to 4 mm.

Preferably, the outer side wall of the turning center of the turning section becomes thicker gradually in the process of extending from the corrugated section to the connecting section.

Preferably, the wave height is 8.8mm and/or the wave pitch is 8.5 mm.

Preferably, the wall thickness of the corrugated section is 0.8 mm.

Preferably, the peak angle is 24 °.

The technical scheme provided by the disclosure at least has the following beneficial effects:

the corrugated pipe with the wave pitch and the wave height provided by the disclosure is easy to demould in the injection molding process, so that the corrugated pipe can be easily manufactured through an injection molding process, and compared with a corrugated pipe manufactured through a blow molding process, the corrugated pipe manufactured through the injection molding process can reduce the generation of excess materials, for example, the excess materials can be reduced by 20%.

In addition, the corrugated pipe is manufactured through an injection molding process, so that the wave height and the wave distance of the corrugated pipe are adjusted to proper sizes, the corrugated pipe has better collapse resistance when the corrugated pipe bears negative pressure, the corrugated pipe also has better motion compensation capability, and the corrugated pipe can be manufactured by utilizing the thermoplastic elastomer through the injection molding process, so that a thermosetting material is avoided, the process complexity is reduced, and the production efficiency is improved.

The corrugated pipe obtained according to the technical scheme can also have the following effects:

the corrugated pipe has the advantages that the corrugated pipe is suitable for an injection molding process, has good durability, motion compensation capability and collapse resistance, is favorable for reducing the weight of the corrugated pipe by adopting the wave height, the wave peak angle and the wave distance of the corrugated section and combining the thickness of the corrugated pipe, and can reduce the weight by 50% compared with the corrugated pipe formed by a traditional injection process.

Drawings

Fig. 1 is a partially cut-away perspective view of one embodiment of a vehicular bellows provided by the present disclosure.

Fig. 2 is a longitudinal sectional view of the vehicle bellows of fig. 1.

FIG. 3 is an enlarged view of one embodiment of a corrugated section.

Description of reference numerals:

1 corrugated section, 11 wave crests, 12 wave troughs, 2 turning sections, 3 connecting sections and 30 annular sealing ribs.

Detailed Description

Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings. It should be understood that the detailed description is intended only to teach one skilled in the art how to practice the disclosure, and is not intended to be exhaustive or to limit the scope of the disclosure.

As shown in fig. 1 and 2, the present disclosure provides a bellows for a vehicle, which may be used in an intake system of the vehicle, for example, a bellows for connecting a supercharger and an air filter, although the present disclosure is not limited thereto. The corrugated pipe comprises a corrugated section 1, a turning section 2 and a connecting section 3, wherein in a natural state, the corrugated section 1 is straight, the turning section 2 is bent, and the turning section 2 is connected with the corrugated section 1 and turns relative to the corrugated section 1. The connecting sections 3 are located at both ends of the whole formed by the turning section 2 and the corrugated section 1 so as to connect the supercharger and the air filter.

The ripple section 1 includes a plurality of wave portions 10 connected in sequence along the axial direction of the ripple section 1 so as to have a plurality of peaks 11 and a plurality of troughs 12, the height difference between the peaks and the troughs is the wave height h, the ripple section 1 may have a form of triangular wave in which the peaks 11 and the troughs 12 have rounded arc shapes, a surface m and a surface n on which two adjacent sides of the peaks 11 are located intersect to form a peak angle θ, and the distance between the adjacent peaks or troughs is the wave distance L. The plurality of wave portions 10 are deformed to be away from each other when the bellows 1 is stretched in its axial direction, and the plurality of wave portions 10 are deformed to be close to each other when the bellows 1 is compressed in its axial direction, so that the bellows functions as motion compensation.

It is understood that each peak 11 and each valley 12 of the corrugated segment 1 in the form of a triangular wave are connected by a substantially straight line in longitudinal section, that is, the portion between the peak 11 and the valley 12 is linear except for the rounded arc portion of the peak 11 and the valley 12.

For those skilled in the art, the feasibility of injection molding and the product performance are realized by matching various parameters of the product, and for the corrugated section 1, the wave height h, the wave crest angle theta and the wave distance L, and the wall thickness b are important adjusting parameters. And it is known that: the smaller the wall thickness b is, the more difficult the injection molding is, the poor vacuum collapse performance is, and the larger the wall thickness b is, the worse the durability experiment and motion compensation performance of the corrugated pipe are; the smaller the crest angle theta is, the more difficult the injection molding demoulding is, the larger the crest angle theta is, the worse the vacuum collapse performance is; the larger the wave height h is, the more difficult the injection molding is to demold, and the smaller the wave height h is, the smaller the amount of compensation of the ripple motion is.

The corrugated section 1 is formed by injection molding a thermoplastic elastomer, and preferably, the corrugated section 1, the turning section 2 and the connecting section 3 are integrally formed by injection molding a thermoplastic elastomer. In order to achieve that the wave 10 has a shape which is easy to release from the injection mould, resistant to vacuum collapse and which facilitates compensation of the wave motion after the injection has been completed, said shape having a wave height h of 5mm to 15mm, preferably 8.8mm, a peak angle theta of 10 deg. to 60 deg., preferably 24 deg., a wall thickness b of 0.5mm to 1.5mm, preferably 0.8 mm.

In order to better achieve the above advantages, the corrugated section 1 further has a wave pitch L set to 6mm to 11mm, preferably 8.5 mm.

In other embodiments, the corrugated tube 1 may not have the turning section 2 and both ends of the corrugated section 1 are directly connected to the connection section 3, the whole corrugated tube 1 is straight, and the corrugated section 1 and the connection section 3 are integrally formed by injection molding of a thermoplastic elastomer, depending on the installation space.

Whether or not there is a turning section 2, the bellows is preferably integrally formed by injection moulding a thermoplastic elastomer.

The thermoplastic elastomer is a thermoplastic material obtained by mixing rubber and plastic, and has high elasticity at normal temperature and plasticity after heating. The thermoplastic elastomer has the advantages of good elasticity, wet skid resistance, low temperature resistance, easy processing and the like.

TPV (thermoplastic vulcanizate) can be given as an example of the above thermoplastic elastomer.

The inventor finds that: the wave pitch L is related to the injection molding demoulding difficulty and the collapse resistance of the corrugated pipe; the wave height h is related to the injection molding demoulding difficulty of the corrugated pipe and the motion compensation capability of the corrugated pipe; the thickness b of the corrugated section 1 is related to the injection molding demolding difficulty, collapse resistance, durability and motion compensation capability of the corrugated pipe.

The corrugated pipe with the wave pitch L and the wave height h provided by the disclosure is easy to demould in the injection molding process, so that the corrugated pipe can be easily manufactured through an injection molding process, and compared with a corrugated pipe manufactured through a blow molding process, the corrugated pipe manufactured through the injection molding process can reduce the generation of excess materials, for example, the excess materials can be reduced by 20%.

In addition, the corrugated pipe is manufactured through an injection molding process, so that the corrugated pipe has proper wave pitch L, better collapse resistance when the corrugated pipe bears negative pressure (the pressure in the pipe is smaller than the pressure outside the pipe), and proper wave height h, and better motion compensation capacity.

The injection molding process can be used for manufacturing the corrugated pipe by utilizing the thermoplastic elastomer, so that thermosetting materials such as EPDM (ethylene propylene diene monomer) rubber and NBR + PVC (rubber-plastic blended mixed foaming material, NBR is nitrile rubber and PVC is polyvinyl chloride) are avoided, the process complexity is reduced, and the production efficiency is improved.

The corrugated section 1 of the corrugated tube has the above-mentioned appropriate thickness b, so that it can be applied to an injection molding process and the corrugated tube has superior durability, motion compensation capability and collapse resistance. Furthermore, the hardness of the thermoplastic elastomer is greater than that of the thermosetting material, and the thickness of the thermoplastic elastomer is smaller than that of the thermosetting material when the same vacuum collapse performance is required, so that the adoption of the thickness b of the corrugated section 1 is also beneficial to the weight reduction of the corrugated pipe, for example, the weight can be reduced by 50% compared with the corrugated pipe formed by the traditional injection process. This also enables the bellows 1 to be reduced in weight.

The wall thickness c of the turning section 2 and the wall thickness a of the connecting section 3 can be greater than the wall thickness b of the corrugated section 1, so that the corrugated pipe has better collapse resistance and sealing performance.

And in order to further enhance the vacuum collapse resistance of the corrugated section, an outer annular sealing rib is arranged at the wave crest of the corrugated section 1 along the circumferential direction of the corrugated pipe, and the height h comprises the height of the annular sealing rib.

In particular, the wall thickness c of the turning section 2 may be 1.2mm to 4mm, preferably 2 mm. The wall thickness a of the connecting section 3 can be 1.2mm to 4mm, preferably 2 mm.

Due to the appropriate wall thickness c of the turnaround section 2, the bellows has better collapse resistance. The bellows has a better sealing performance due to the appropriate wall thickness a of the connecting section 3. The turning center outer side wall of the turning section 2 becomes gradually thicker in the course of extending from the bellows section 1 to the connecting section 3. It will be appreciated that the outer side wall of the steering centre of the steering section 2 is of a length in the range from the same wall thickness as the inner side wall of the steering centre, for example from 1.2mm to 4mm, and the "length" is less than the total length of the outer side wall of the steering centre.

The connecting section 3 may be cylindrical in shape, provided with a band connection, the inner surface of which is formed with an annular sealing rib 30, the radial dimension of the annular sealing rib 30 may be, for example, 0.5mm, and the axial dimension may be, for example, 0.8 mm. The annular sealing rib 30 is used to improve the sealing performance of the bellows when the connection section 3 connects the supercharger and the air filter, for example, when the connection section 3 is tightly fitted by a band at the radially outer side of the connection section 3, the annular sealing rib 30 abuts against the portion of the supercharger and the portion of the air filter to be connected.

The blow molding process can only guarantee the external precision but has difficulty in guaranteeing the internal precision, and particularly for small-sized structures such as the annular sealing rib 30, the blow molding process usually has difficulty in meeting the precision requirement, which results in poor sealing effect of the corrugated pipe manufactured by the blow molding process.

Although the annular sealing rib 30 can be manufactured by the injection process, the rubber density is high, so that the weight of the corrugated pipe is increased, and the connecting section 3 needs to be made thicker to meet the sealing requirement, so that the weight of the corrugated pipe is increased, and the manufacturing cost of the corrugated pipe is increased.

The corrugated pipe provided by the disclosure can form small-size annular sealing ribs meeting the high-precision requirement due to the injection molding process, so that the corrugated pipe has better sealing performance.

In the embodiment shown in fig. 3, each peak 11 of the wave segment 1 has a protrusion, and the wave height h of the wave 10 is the dimension from the radially outermost side of the protrusion to the radially outermost side of the wave trough 12.

The following two tables illustrate the performance of four samples of the air induction system bellows provided by the present disclosure.

Table 1 bellows endurance test results

TABLE 2 bellows leakage and vacuum collapse Experimental test results

As can be seen from table 1, the two samples passed the durability test with a leakage pressure of 0 before and after the test and no crack in the bent or free state.

It can be seen from table 2 that the leakage pressure of the two samples after the experiment both meets the requirements, and both samples pass the leakage experiment. The two samples can bear negative pressure of 32.16kpa and 29.92kpa respectively, and the collapse pressure of the two samples meets the requirement.

It should be understood that the above-described embodiments are exemplary only, and are not intended to limit the present disclosure. Various modifications and alterations of the above-described embodiments may be made by those skilled in the art in light of the teachings of this disclosure, without departing from the scope of this disclosure.

Claims

1. A corrugated pipe for a vehicle is provided with a corrugated section (1) and a connecting section (3), wherein the connecting section (3) is provided with a clamp connection part, and the inner surface of the clamp connection part is provided with an annular sealing rib (30); thereby ripple section (1) sets up to a plurality of wave form portions (10) that connect gradually have a plurality of crests (11) and a plurality of trough (12), the crest with the difference in height of trough is wave height (h), adjacent two the crest or adjacent two the distance between the trough is wave distance (L), its characterized in that, the bellows adopts the whole injection moulding of thermoplastic elastomer, wave height (h) is 5mm to 15mm, wave distance (L) is 6mm to 11 mm.

2. Vehicle bellows according to claim 1, wherein the wall thickness (b) of the bellows segment (1) is 0.5mm to 1.5 mm.

3. The vehicular corrugated pipe according to claim 1, wherein the corrugated section (1) has a form of a triangular wave, and surfaces of two adjacent sides of each of the crests (11) of the corrugated section (1) intersect to form a crest angle (θ), and the crest angle (θ) is 10 ° to 60 °.

4. Corrugated pipe for vehicles according to claim 1, characterized in that it is further provided with a turning section (2), the turning section (2) turning in relation to the corrugated section (1), the connection section (3) being located at both ends of the whole formed by the turning section (2) and the corrugated section (1), the wall thickness (c) of the turning section (2) being greater than the wall thickness (b) of the corrugated section (1) and/or the wall thickness (a) of the connection section (3) being greater than the wall thickness (b) of the corrugated section (1).

5. Vehicle bellows according to claim 4, wherein the wall thickness (c) of the turning section (2) is 1.2 to 4mm and/or the wall thickness (a) of the connecting section (3) is 1.2 to 4 mm.

6. Vehicle bellows according to claim 5, wherein the outer side wall of the turning centre of the turning section (2) becomes thicker gradually as it goes from the bellows section (1) to the connection section (3).

7. Vehicle bellows according to claim 1, wherein the wave height (h) is 8.8mm and/or the wave pitch (L) is 8.5 mm.

8. Vehicle bellows according to claim 2, wherein the wall thickness (b) of the bellows segment (1) is 0.8 mm.

9. Vehicle bellows according to claim 3, wherein the peak angle (θ) is 24 °.