CN1177695A

CN1177695A - Gas tube

Info

Publication number: CN1177695A
Application number: CN 97118213
Authority: CN
Inventors: 野田达人; 加藤善久; 椿公男
Original assignee: Toyoda Gosei Co Ltd
Current assignee: Toyoda Gosei Co Ltd
Priority date: 1996-09-02
Filing date: 1997-09-02
Publication date: 1998-04-01
Anticipated expiration: 2017-09-02
Also published as: JPH1078172A; CN1070276C

Abstract

An air hose 10 is formed to have the first rubber layer 12 occupying the main part thereof, and the second rubber layer 14 formed on the external surface of the first rubber layer 12. Furthermore, the first rubber layer 12 is a rubber layer made of acrylonitrile-butadiene copolymer (NBR), and the second rubber layer 14 is a rubber layer made of chlorosulfonated polyethylene (CSM). In this case, the first rubber layer 12 and the second rubber layer 14 are concurrently molded, using a hose extruder and the thickness of the second rubber layer 14 has a value between 0.2mm and about 0.6mm. Also, the air hose 10 displays a ozone resisting function via the second rubber layer 14, regardless of thickness as small as 0.3mm, and elasticity or restorability as a hose can also be provided, due to the first rubber layer 12 formed to have approximately the same thickness as an NBR monolayer hose, as a result of applying small thickness to the second rubber layer 14.

Description

Tracheae

The present invention relates to a kind of tracheae that is connected with Pneumatic actuator.

Usually, require such tracheae to have various features such as higher ductility and productivity or the like.For example, be installed in the various Pneumatic actuator in the vehicle, these Pneumatic actuator do not exist only in the engine compartment that the various devices such as motor wherein closely and effectively are installed, and be present near near the body bottom of fuel tank, therefore, require tracheae to be connected with Pneumatic actuator by dog leg piping.Be under the situation that bent state installs at tracheae, when tracheae is deformed into to a certain degree during in bending, and if keep this distortion, will stop air to pass through tracheae.Therefore, the tracheae that requires to be used for vehicle has elasticity and restorability, the individual layer tracheae that uses rubber material good aspect elasticity and restorability, constitutes such as hycar (NBR).Be used for tracheae on the vehicle and comprise the tracheae that is connected with one-way valve with (for example) vacuum control valve, vacuum switch, membrane valve in the system of air-breathing and vent systems, fuel vaporization system and so on.

Yet, though tracheae traditional, individual layer, NBR material system is being good aspect elasticity and the restorability, but when in the vehicle that they are used for using in various open-air atmospheres, they sometimes will stand the erosion of ozone, thereby crack on the outer surface.On the other hand, when only using the good rubber material of ozone resistance, when replacing NBR, will being easy to be retained in the tracheae because of compressing the permanent permanent deformation that produces, thereby damaging elasticity and restorability such as chlorosulfonated polyethylene (CSM).

The invention solves the problems referred to above, its objective is provides a kind of except having elasticity and restorability, also has the tracheae of ozone resistance.

In order to solve above-mentioned task, tracheae of the present invention is a kind of tracheae that is connected on the Pneumatic actuator, it has first rubber layer and second rubber layer, first rubber layer comprises the butadiene rubber material, it defines an air passageways, second rubber layer comprises the chlorosulfonated polyethylene rubber material, and it is formed on the outer surface of first rubber layer, and has the thickness of about 0.2mm to about 0.6mm.

Fig. 1 is the sectional view of the amplification of tracheae 10 of the present invention, label 12 expressions first rubber layer, label 14 expressions second rubber layer;

Fig. 2 has shown the determination test that carries out on tracheae 10;

Fig. 3 is the chart that is presented at the result of the determination test that carries out on the tracheae 10.

In the tracheae with said structure of the present invention, when the external diameter of tracheae is identical with traditional tracheae, Guarantee near the thickness of thickness near traditional individual layer tracheae of first rubber layer, specifically, first rubber The thickness of second rubber layer on the glue-line outer surface approximately is 0.2mm to 0.6mm, like this, and butadiene rubber The performance of material, be that elasticity and restorability are presented by first rubber layer. On the other hand, although second Rubber layer has about 0.2mm to the thinner thickness of 0.6mm, but because CSM material Material has good ozone resistance, so this second rubber layer that is exposed in the air can be resisted invading of ozone Erosion. Therefore, according to the present invention, can provide a kind of tracheae, it also has except elasticity and restorability Ozone resistance.

In this case, second rubber layer preferably has about 0.2mm or above thickness, with facility With a hose squeezing make-up machine, obtain the evenly rubber layer (second rubber layer) of formation by two material extruding. In addition, second rubber layer preferably has about 0.6mm or following thickness, in order to guarantee first rubber layer Thickness near the thickness of traditional individual layer tracheae, namely keep the external diameter of tracheae near traditional tracheae external diameter, And the proper property of tracheae (air-tightness of passage) and elasticity and restorability do not have too many infringement.

The embodiment of tracheae of the present invention then, is described by example.

Fig. 1 is the sectional view of the amplification of the tracheae 10 in the present invention's first example.As shown in Figure 1, tracheae 10 has first rubber layer 12 that accounts for the tracheae major component and is formed on second rubber layer 14 on the first rubber layer outer surface.First rubber layer 12 comprises hycar (NBR), and second rubber layer 14 comprises chlorosulfonated polyethylene (CSM).Here, tracheae 10 have be used in vehicle in identical internal diameter and the external diameter of conventional monolayers tracheae, its internal diameter, promptly the internal diameter of first rubber layer 12 approximately is 7mm.Its external diameter, promptly the external diameter of second rubber layer 14 approximately is 12mm, and its wall thickness approximately is 2.5mm.Second rubber layer 14 utilizes the extruding synchronously of the flexible pipe machine for extrusion molding and first rubber layer to come out.That is, it utilizes a machine for extrusion molding and first rubber layer, 12 coaxial compression mouldings to come out, and like this, second rubber layer has the thickness of about 0.3mm.

To be described in the determination test that carries out on the tracheae 10 of this example below.The tracheae of comparing (relatively tracheae) is the individual layer tracheae made from NBR, and it has above-mentioned internal diameter and external diameter.At first, prepare the tracheae 10 in this example and compare tracheae, and allow them stand ozone resistance test with following manner.As shown in Figure 2, at tracheae crooked 180 degree of about neutral position with suitable length, and it is fixing firmly at suitable position with a rope.It is used as test specimen.Then, this test specimen was placed in room temperature 16-24 hour.Then, with test specimen be placed on high temperature and high-concentrated ozone experimental enviroment (temperature: 40 ± 2 ℃, ozone concentration: in 50 ± 5pphm), calculate with instruments such as magnifying glasses and see in the time of taking place on the test specimen surface to be disappeared before the crackle.Under situation,, and under the situation of the test specimen of tracheae relatively, after 10 hours, just can find crackle even, also do not find crackle through after 70 hours according to the test specimen of the tracheae 10 of this example.Therefore, can see the tracheae 10 anti-ozone of this example.

Here, the thickness that presents the NBR rubber layer (first rubber layer 12) of elasticity and restorability is 1.7mm approximately, and it is 85% of the traditional about 2mm of individual layer tracheae thickness approximately.Therefore, as described below, tracheae 10 can present the performance roughly the same with traditional tracheae.

At first, introduce the tightness of the intrinsic performance-passage of tracheae.With the tracheae in the above-mentioned example 10 (internal diameter: 7mm; External diameter: 12mm) enlarge and be connected that this tracheae will connect, corresponding pipe (external diameter: 8mm), after being connected on the pipe, tracheae was placed 24 hours in 120 ℃ heating environment with the attachment portion of Pneumatic actuator.Then, check the sealing (tightness) of attachment portion.That is, make tracheae 10 force heat ageing, and check sealing in this case.A tracheae 10 and a tracheae (relatively tracheae) at this example are gone up and are measured sealing, and wherein, the thickness of second rubber layer 14 of this example tracheae 10 is 0.2mm approximately, 0.3mm, 0.4mm, and 0.6mm, and relatively the thickness of second rubber layer 14 of tracheae is 0.8mm, surpasses scope of the present invention.Determine sealing with following manner.After being positioned in the above-mentioned heating environment, the free end of the tracheae that will be connected with pipe by suitable mode stops up, and allows water enter tracheae by the pipe injection.Then, measure the pressure (injection pressure) that begins the water leakage in the pipe joint.Fig. 3 has shown measurement result.

As shown in Figure 3, aging even tracheae is heated when the thickness of second rubber layer 14 is in the 0.2mm-0.6mm scope, sealing is the about 20N/cm that surpasses lower limit ²To about 24.5N/cm ²On the other hand, when second rubber layer 14 has the thickness that surpasses above-mentioned scope, sealing is lower than lower limit, and the performance of tracheae suffers damage.That is, because the thickness of second rubber layer 14 is in above-mentioned scope, the thickness of first rubber layer 12 can be generally identical with NBR individual layer tracheae, is 70-90% in this example, and can obtains the sealability roughly the same with traditional tracheae.On the other hand, when the thickness of second rubber layer 14 surpasses above-mentioned scope (0.8mm), the thickness of first rubber layer 12 is that 60%, the first rubber layer 12 of individual layer tracheae is too thin, thereby damages its sealing.Specifically, the sealing lower limit is a needed minimum when tracheae is connected with the Pneumatic actuator of vehicle.

Because sealing is meant the sealing after tracheae enlarges and is connected on the pipe, therefore, it is to obtain on the basis of the elasticity of tracheae and restorability.Like this, the tracheae 10 of this example also presents the elasticity and the restorability that are suitable for actual use reliably except having above-mentioned ozone resistance.

Elasticity and restorability about tracheae can obtain following result.Under the situation of NBR individual layer tracheae, because elasticity and the restorability of NBR itself, when it was compressed under 120 ℃ * 22 hours situation, it was 13-20% approximately that its compression becomes remaining shape.On the other hand, under the situation of the tracheae 10 of thickness in above-mentioned scope of first rubber layer 12, compressed residual distortion under the same conditions is 20-27% approximately, and like this, the elasticity and the restorability that are similar to traditional NBR individual layer tracheae can reach actual usage level.That is, except anti-ozone, the tracheae 10 of this example can present elasticity and restorability.

The invention is not restricted to above-mentioned example and embodiment, use can take various forms under the situation that does not exceed the scope of the invention.

Claims

1. a tracheae that is connected on the Pneumatic actuator is characterized in that, it has first rubber layer and second rubber layer, and first rubber layer comprises the butadiene rubber material and limits an air passageways; Second rubber layer comprises the chlorosulfonated polyethylene rubber material, and described second rubber layer is formed on the outer surface of first rubber layer, and has the thickness of 0.2mm to 0.6mm.