JP4461326B2 - Automotive fuel tank piping connector - Google Patents

Description

  The present invention relates to a connector for piping in a fuel tank of an automobile.

  Conventionally, automobile fuel tanks (usually metal tanks) are first subjected to surface treatment (painting and drying) at a high temperature, and then various valves and piping are attached to the upper surface of the tank. High heat resistance was not required for valves and piping. Thereafter, in order to cope with the environmental regulations of automobiles and the lengthening of the warranty period, valves and pipes attached to the upper surface of the fuel tank have been moved into the tank (for example, see Patent Document 1).

  In this case, since the surface treatment is performed at a high temperature after valves and piping are attached in advance in the fuel tank, the piping disposed in the tank can withstand a surface treatment at a temperature higher than the normal use environment. Heat resistance is required.

Here, a combination of a rubber hose and a metal pipe may be employed as the heat-resistant piping, but a combination of a resin tube and a resin connector is desired in terms of weight reduction and assembly workability.
JP 2003-49976 A

  Therefore, the present invention is intended to provide a resin connector that can withstand the surface treatment of the fuel tank and that does not cause any inconvenience during actual use.

  In order to solve the above problems, the present invention takes the following technical means.

(1) A connector for piping in an automobile fuel tank according to the present invention includes a housing portion 5 having a connecting end portion 2 of a resin tube 1 and an insertion end portion 4 of a male pipe 3, and a flange portion 6 for retaining the male pipe 3. And the housing part 5 is made of a material having a melting point of 180 ° C. or higher (ASTM D789-94) and a deflection temperature under load of 170 ° C. (ASTM D648-95, a load of 1.8 MPa). The retainer 7 is made of a polybutylene naphthalate elastomer having a melting point of 180 ° C. or higher (ASTM D789-94) and a flexural modulus of 1000 to 3000 MPa (ASTM D790-95a). After heat treatment at 170 ° C. for 3 hours, it is left in an oven at 65 ° C. for 500 hours in a state immersed in deteriorated fuel oil. Even after, the strength retention of the retainer 7, characterized in that 50% or more.

  In this automobile (including trucks and other special vehicles) fuel tank piping connectors, the melting point of the resin housing material and the deflection temperature under load are defined, and the melting point and flexural modulus of the resin retainer material are defined. Therefore, it can withstand the surface treatment of the fuel tank and does not cause any inconvenience during actual use.

  That is, when the melting point (ASTM D789-94) of the material of the housing part is less than 180 ° C., it melts and deforms during the surface treatment of the fuel tank, and the function as a connector cannot be maintained. Also, when the deflection temperature under load (ASTM D648-95, load 1.8 MPa) is less than 170 ° C., the load applied during the surface treatment of the fuel tank (tightening force from the connected resin tube, male pipe or O-ring) Deformation occurs due to the pressing force of the connector, and the function as a connector cannot be maintained.

  When the melting point of the retainer material (ASTM D789-94) is less than 180 ° C., the retainer melts and deforms during the surface treatment of the fuel tank, and the function as a connector cannot be maintained. In addition, when the flexural modulus (ASTM D790-95a) is less than 1000 MPa, the retainer strength decreases and the male pipe is easily pulled out, which is inappropriate for actual use (during travel). When the male pipe is attached or detached after being deformed, the retainer is difficult to deform, and the male pipe becomes difficult or impossible to attach or detach.

  Specifically, as the material of the housing part, PTFE (polytetrafluoroethylene) with filler, PA11 (polyamide 11) with filler, PA6 (polyamide 6) with filler, PA66 (polyamide 66) with filler, PA6 / 12 with filler (polyamide 6/12), PA46 with filler (polyamide 46), PA6T with filler (polyamide 6T), PPA with filler (polyphthalamide), PA9T with filler (polyamide 9T), MXD6 with filler (polymetaxylylene apamid), PET with filler (polyethylene terephthalate), PBT with filler (polybutylene terephthalate), PBN with filler (polybutylene naphthalate), PCT with filler (polycyclohexane) Terephthalate), LCP (liquid crystal polymer), filled PPS (polyphenylene sulfide), filled PEEK (polyetheretherketone) It can be mentioned PES (polyether sulfone).

  Specific examples of the retainer material include PA11 (polyamide 11), PA6 / 12 (polyamide 6/12), modified PA66 (modified polyamide 66), and PBN elastomer (polybutylene naphthalate elastomer).

 (2) As a material of the housing part, a material made of any of aliphatic polyamide, aromatic polyamide, polybutylene naphthalate, polyphenylene sulfide, or a blend of two or more thereof may be used. Specifically, PA11 with filler (polyamide 11), PA6 with filler (polyamide 6), PA66 with filler (polyamide 66), PA6 / 12 with filler (polyamide 6/12), PA46 with filler ( Polyamide 46), PA6T with filler (polyamide 6T), PA9T with filler (polyamide 9T), PBN with filler (polybutylene naphthalate), PPS with filler (polyphenylene sulfide), or these 2 The blended product described above may be used.

  If comprised in this way, while a housing part can endure the temperature of the surface treatment of a fuel tank, it is excellent in deteriorated fuel oil property.

(3) A material made of any one of polyamide 11 (PA11) and polybutylene naphthalate (PBN) elastomer or a blend thereof may be used as the material of the retainer.

  If comprised in this way, while a retainer can endure the temperature of the surface treatment of a fuel tank, it is excellent in deteriorated fuel oil property.

(4) A filler (a material for improving strength and rigidity such as glass fiber and carbon fiber) can be added to the material of the retainer.

  If the housing material or retainer material deteriorates and the strength decreases significantly, connector damage (male pipe disconnection) due to internal pressure applied to the piping or connector damage due to vibration during travel may occur. A high rate is desired.

  Since the housing portion needs to have strength, it is preferable to use a material containing a filler, although it depends on the material (when the filler is contained, the strength is less likely to decrease). On the other hand, since the retainer needs to be deformed when the male pipe is attached to or detached from the housing, it can be adjusted so that the elastic modulus is 3000 MPa or less even if the filler is not filled or contained depending on the material. Desirable (if the elastic modulus becomes too high, it becomes hard and difficult to deform).

  The present invention is configured as described above and has the following effects.

  In this automotive fuel tank piping connector, the melting point of the housing material and the deflection temperature under load are regulated, and the melting point and bending elastic modulus of the retainer material are regulated. It is possible to provide a resin connector that does not cause any inconvenience.

  Embodiments of the present invention will be described below with reference to the drawings.

  As shown in FIGS. 1 and 2, the automotive fuel tank piping (in-tank piping) quick connector of this embodiment includes a housing portion having a connection end 2 of a resin tube 1 and an insertion end 4 of a male pipe 3. 5 and a retainer 7 for performing an attaching / detaching operation through a flange portion 6 for preventing the male pipe 3 from coming off. The retainer 7 has an inward projecting piece 8 that can be advanced and retracted inward. By deforming the inward projecting piece 8, the retainer 7 is attached to and detached from the retaining flange portion 6 of the male pipe 3. The operation is performed. 9 is a rubber main O-ring, 10 is a rubber stem O-ring, and 11 is a resin stopper for preventing the main O-ring 9 from coming off.

  The material of the housing part 5 is made of a thermoplastic resin having a melting point (ASTM D789-94) of 180 ° C. or higher and a deflection temperature under load (ASTM D648-95, load 1.8 MPa) of 170 ° C., and the retainer 7 This material is made of a thermoplastic resin having a melting point of 180 ° C. or higher (ASTM D789-94) and a flexural modulus of 1000 to 3000 MPa (ASTM D790-95a).

  A filler (a material for improving strength and rigidity such as glass fiber and carbon fiber) can be added to the material.

If the material of the housing part 5 or the material of the retainer 7 deteriorates and the strength decreases greatly, there is a possibility of connector destruction due to internal pressure applied to the pipe (male pipe disconnection) or connector destruction due to vibration during travel. A high strength retention is desired.
Since it is necessary to give the housing part 5 strength, it is preferable to use a material containing a filler, although depending on the material (deterioration is unlikely to occur when the filler is contained). On the other hand, since the retainer 7 needs to be deformed when the male pipe is attached to or detached from the housing portion 5, it is adjusted so that the elastic modulus is 3000 MPa or less even if the filler is not filled or contained, depending on the material. Is desirable (If the elastic modulus becomes too high, it becomes hard and difficult to deform.)
Specifically, the material of the housing part 5 is PTFE (polytetrafluoroethylene) with filler, PA11 (polyamide 11) with filler, PA6 (polyamide 6) with filler, PA66 (polyamide 66) with filler , PA6 / 12 with filler (polyamide 6/12), PA46 with filler (polyamide 46), PA6T with filler (polyamide 6T), PPA with filler (polyphthalamide), PA9T with filler (polyamide 9T) , MXD6 with filler (polymetaxylylene apamid), PET with filler (polyethylene terephthalate), PBT with filler (polybutylene terephthalate), PBN with filler (polybutylene naphthalate), PCT with filler (poly) Cyclohexane terephthalate), LCP (liquid crystal polymer), filled PPS (polyphenylene sulfide), filled PEEK (polyetheretherketone) , Mention may be made of PES (polyether sulfone).

  Table 1 shows the melting point (ASTM D789-94) and deflection temperature under load (ASTM D648-95, load 1.8 MPa).

前記リテーナ７の材料として、具体的には、PA11（ポリアミド11）、PA6/12（ポリアミド6/12）、変性PA66（変性ポリアミド66）、PBNエラストマー（ポリブチレンナフタレートエラストマー）を挙げることができる。

Specific examples of the material of the retainer 7 include PA11 (polyamide 11), PA6 / 12 (polyamide 6/12), modified PA66 (modified polyamide 66), and PBN elastomer (polybutylene naphthalate elastomer). .

  Table 2 shows the melting point (ASTM D789-94) and flexural modulus (ASTM D790-95a). Note that these do not contain a filler.

次に、この実施形態の自動車燃料タンク内配管用コネクタの使用状態を説明する。

Next, the usage state of the automobile fuel tank piping connector of this embodiment will be described.

  In this automobile fuel tank piping connector, the melting point and the deflection temperature under load of the resin housing part 5 are specified, and the melting point and bending elastic modulus of the resin retainer 7 are specified. There is an advantage that it can withstand the processing and does not cause any inconvenience during actual use.

  That is, when the melting point (ASTM D789-94) of the material of the housing part 5 is less than 180 ° C., it melts and deforms during the surface treatment of the fuel tank, and the function as a connector cannot be maintained. When the deflection temperature under load (ASTM D648-95, load 1.8 MPa) is less than 170 ° C., the load applied during the surface treatment of the fuel tank (clamping force from the connected resin tube 1, male pipe 3 or Deformation occurs due to the pressing force from the O-ring, and the function as a connector cannot be maintained.

  When the melting point (ASTM D789-94) of the material of the retainer 7 is less than 180 ° C., the retainer 7 is melted and deformed during the surface treatment of the fuel tank, and the function as a connector cannot be maintained. Also, when the flexural modulus (ASTM D790-95a) is less than 1000 MPa, the strength of the retainer 7 is reduced and the male pipe 3 is easily pulled out, so it is inappropriate for actual use (running). When the retainer 7 is deformed and the male pipe 3 is attached / detached, the retainer 7 is difficult to deform, and the male pipe 3 is difficult or impossible to attach / detach.

Next, the configuration of the present invention will be described more specifically.
(1) Deterioration fuel oil resistance test of housing part 5 As shown in FIG. 3, a sample assembly in which a resin tube 1 and a male pipe 3 are connected to a connector for piping in an automobile fuel tank is prepared, and heat treatment is performed at 170 ° C. for 3 hours. (Assuming surface treatment of metal tank). Thereafter, the sample assembly was left in an oven at 65 ° C. for 500 hours in a state where it was immersed in deteriorated fuel oil (alcohol-containing gasoline and t-BHPO [tertiary butyl hydroperoxide]).

  The sample assembly (A) to which only the heat treatment was applied and the sample assembly (B) to which the deteriorated fuel oil was further immersed on the heat treatment were attached to a tensile tester configured as shown in FIG. The load when the connector breaks was measured. Then, the measured value b / a (%) from the measured value a of the fracture strength of the sample assembly (A) subjected only to heat treatment and the measured value b of the fracture strength of the sample assembly (B) immersed in deteriorated fuel oil after heat treatment. The strength retention after immersion of deteriorated fuel oil was evaluated by calculating the value of. Here, when the strength retention was 50% or more, the degree of deterioration of the material itself was evaluated as low and good.

  (1) As a result, the strength retention after dipping in deteriorated fuel oil when the material of the housing part 5 is made of polyamide 11 containing 30% filler is 60% (50% or more). The degree of degradation was low and good.

  (2) In addition, the strength retention ratio after immersion of deteriorated fuel oil in the case of polyamide 6/12 containing 33% filler in the material of the housing part 5 is 60% (50% or more), and the material itself The degree of degradation was evaluated as low and good.

  (3) Further, the strength retention after immersion in deteriorated fuel oil when the material of the housing part 5 is made of polyamide 66 containing 33% filler is 60% (50% or more), and the material itself deteriorates. The degree was rated low and good.

  (4) In addition, the strength retention rate after immersion of deteriorated fuel oil in the case of polyamide 9T containing 30% filler in the material of the housing part 5 is 70% (50% or more), and the material itself deteriorates. The degree was rated low and good.

  (5) Further, the strength retention after immersion of deteriorated fuel oil in the case where polybutylene naphthalate containing 30% filler in the material of the housing part 5 is 90% (50% or more), and the material itself The degree of degradation was evaluated as low and good.

  (6) In addition, the strength retention rate after immersion in deteriorated fuel oil is 95% (50% or more) when the material of the housing part 5 is made of polyphenylene sulfide containing 30% filler, and the material itself deteriorates. The degree was rated low and good.

(2) Deterioration fuel oil resistance test of retainer A sample dumbbell of JIS K7162 test piece 5A (thickness 1 mm) is formed as a retainer material, and heat treatment at 170 ° C for 3 hours (assuming surface treatment of metal tank) went. Thereafter, the sample dumbbell was left in an oven at 65 ° C. for 500 hours in a state of being immersed in deteriorated fuel oil (alcohol-containing gasoline and t-BHPO [tertiary butyl hydroperoxide]).

  A sample dumbbell (C) with only heat treatment and a sample dumbbell (D) that has been further immersed in deteriorated fuel oil on the heat treatment are attached to a tensile tester, and the load is applied when the dumbbell breaks. It was measured. Then, the measured value d / c (%) from the measured value c of the breaking strength of the sample dumbbell (C) subjected only to the heat treatment and the measured value d of the breaking strength of the sample dumbbell (D) immersed in the deteriorated fuel oil after the heat treatment. The strength retention after immersion of deteriorated fuel oil was evaluated by calculating the value of. Here, when the strength retention was 50% or more, the degree of deterioration of the material itself was evaluated as low and good.

  (1) As a result, when the retainer material is polyamide 11 with no filler added, the strength retention after immersion in deteriorated fuel oil is 60% (50% or more), and the deterioration degree of the material itself is low. It was evaluated as good.

  (2) Also, when the retainer material is polyamide 11 containing 8% filler, the strength retention after immersion in deteriorated fuel oil is 60% (50% or more), and the deterioration degree of the material itself is It was evaluated as low and good.

  (3) In addition, when the retainer material is polybutylene naphthalate elastomer with no filler added, the strength retention after immersion in deteriorated fuel oil is 80% (50% or more), and the degree of deterioration of the material itself Was rated as low and good.

(3) As described above, the material of the housing portion 5 is made of any one of polyamide 11 (PA11), polyamide 6/12 (PA6 / 12), polyamide 66 (PA66), and polybutylene naphthalate (PBN). If the material of the retainer 7 is made of any one of polyamide 11 (PA11) and polybutylene naphthalate (PBN) elastomer, it can withstand the temperature of the surface treatment of the fuel tank and is deteriorated fuel oil (with alcohol) There is an advantage that it is excellent in gasoline and t-BHPO (tertiary butyl hydroperoxide).

  By defining the melting point and load deflection temperature of the housing material and by defining the melting point and bending elastic modulus of the retainer material, it can withstand high-temperature surface treatment of the fuel tank and does not cause any inconvenience during actual use. The present invention can be applied to the use of automobile resin connectors.

The half sectional view explaining the state which attached the resin tube and the male pipe in embodiment of the connector for piping in the fuel tank of this invention. FIG. 2 is a half cross-sectional view illustrating a state before a male pipe or the like is attached to a housing portion with the automobile fuel tank piping connector of FIG. 1. The figure explaining the deterioration-proof fuel oil test of a housing part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Resin tube 2 Connection end part 3 Male pipe 4 Insertion end part 5 Housing part 6 Flange part 7 Retainer

Claims (3)

A housing part (5) having a connection end part (2) of the resin tube (1) and an insertion end part (4) of the male pipe (3), and a retaining flange part (6) of the male pipe (3) And a retainer (7) for performing attachment / detachment operation, and the material of the housing part (5) is a melting point (ASTM D789-94) of 180 ° C. or higher and a deflection temperature under load of 170 ° C. (ASTM D648-95, load). The material of the retainer (7) is a polybutylene having a melting point of 180 ° C. or higher (ASTM D789-94) and a flexural modulus of 1000 to 3000 MPa (ASTM D790-95a). A sample dumbbell made of phthalate elastomer and having the size of JIS K7162 test piece 5A (thickness 1 mm) as a test for resistance to deterioration of the retainer (7). After the sample dumbbell (C) to which only heat treatment at 170 ° C. × 3 hours was applied and heat treatment at 170 ° C. × 3 hours, gasoline containing alcohol and t-BHPO (tertiary butyl hydroperoxide) Measure the load when the dumbbell breaks by attaching the sample dumbbell (D) left in an oven at 65 ° C. for 500 hours while immersed in a deteriorated fuel oil consisting of And
The value of d / c (%) is calculated from the measured value c of the fracture strength of the sample dumbbell (C) subjected only to heat treatment and the measured value d of the fracture strength of the sample dumbbell (D) immersed in deteriorated fuel oil after heat treatment. A connector for piping in an automobile fuel tank, characterized in that the strength retention after immersion of deteriorated fuel oil is 50% or more. A housing part (5) having a connection end part (2) of the resin tube (1) and an insertion end part (4) of the male pipe (3), and a retaining flange part (6) of the male pipe (3) And a retainer (7) for performing attachment / detachment operation, and the material of the housing part (5) is a melting point (ASTM D789-94) of 180 ° C. or higher and a deflection temperature under load of 170 ° C. (ASTM D648-95, load). The material of the retainer (7) is a polybutylene having a melting point of 180 ° C. or higher (ASTM D789-94) and a flexural modulus of 1000 to 3000 MPa (ASTM D790-95a). consists phthalate elastomer, a deterioration resistance fuel oil tests housing portion (5), and a resin tube (1) to the vehicle fuel tank pipe connector opacity The sample assembly (A) connected with the pipe (3) was subjected to heat treatment at 170 ° C. for 3 hours, and heat treatment at 170 ° C. for 3 hours. The sample assembly (B) of the retainer (7) left in an oven at 65 ° C. for 500 hours while immersed in a deteriorated fuel oil made of BHPO (tertiary butyl hydroperoxide) is attached to a tensile tester and loaded. Measure the load when the connector breaks by applying a load, measure the fracture strength a of the sample assembly (A) with heat treatment only, and the fracture strength of the sample assembly (B) immersed in deteriorated fuel oil after heat treatment from the measured value b, motor fuel data that b / a (%) values strength retention rate after deterioration fuel oil immersion obtained by calculating the is characterized in that 50% or more Connector for-click inside of the pipe. The automobile fuel tank according to claim 1 or 2, wherein a material comprising any of aliphatic polyamide, aromatic polyamide, polybutylene naphthalate, polyphenylene sulfide or a blend of two or more thereof is used as the material of the housing part (5). Connector for internal piping.

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