JP2860239B2 - Resin-coated spring member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

FIELD OF THE INVENTION This invention relates to a mosquito puller, pump,
The present invention relates to a resin-coated spring member used for a part having chemical resistance such as a valve.

2. Description of the Related Art Conventionally, as a spring member used for a portion as described above, for example, as shown in FIG.
The outer surface of a coil spring 12 formed by winding a wire rod 12a made of stainless steel is covered with a coating tube 13 made of FEP resin (tetrafluoroethylene / hexafluoropropylene copolymer), and the outside thereof is made of PTFE resin (polytetrafluoroethylene). after coating the coating tube 14, coating tube 13 is heat treated at an appropriate temperature thermally welded, the coating tube 14 is tree butter coated spring 11 which is heat-shrinkable.
On the other hand , as shown in FIG. 7, the outer surface of a coil spring 16 formed by winding a SUS wire 16a is coated with a PTFE resin coating tube 17, and then heat-treated at an appropriate temperature to thermally weld the coating tube 17. and certain heat shrunk tree fat coated spring 15 also. However, the resin-coated spring 11 of the conventional example shown in FIG. 6 is not suitable for use under high-temperature conditions because the heat-resistant temperature of the coated tube 13 formed of FEP resin is as low as 270 ° C. In addition, as shown in Table 1, FEP resin has poor stress crack resistance, and is subjected to stress due to repeated compression and restoration.
A crack may occur in a part of the coating tube 13 at a relatively early stage after use. That is, the melting point of FEP is 270 ° C., the melting point of PTFE is 327 ° C.,
Since the melting temperature difference between these two is about 60 ° C., the heat shrinkage of PTFE is weak in the integral molding, and there is a problem such as peeling of the coating layer. , The stress is concentrated and causes cracks. In other words, FEP has low crack resistance of the resin itself, and in addition, peeling of the metal material and the resin causes the crack resistance to be further reduced. On the other hand, in FIG.
The illustrated resin-coated spring 15 has a coating tube 17 made of PTFE resin and has a heat resistant temperature of 327.
Because of the high temperature of ℃ and the good releasability inherent in the PTFE resin, welding is difficult and the welded portion of the coating tube 17 is easily peeled off. Further, it is difficult to weld the coating tube 17 made of PTFE resin to the coil spring 16, and a gap may be formed between the joining surfaces of the coil spring 16 and the coating tube 17. When the coating tube 17 is cracked by the stress caused by the repeated compression and restoration, there is a problem that the entire coil spring 16 is corroded by a chemical solution, gas or the like penetrating from the crack. Further, in the conventional configuration shown in FIGS. 6 and 7, since both ends of the wires 12a and 16a have corners, there is a problem that the covering member is damaged during bending and extension of the spring. There was a problem that corrosion resistance sometimes deteriorated. By the way , JP-A-6
There is a thermofluid fluororesin coating method as described in JP-A-3-102920. In this method, the surface of the article is, for example, PTF
When coated with a fluororesin shrinkable tube such as E, a primer containing a fluororesin such as PFA, which has a lower melting point than the fluororesin heat shrinkable tube covering the surface of the article, is spray-coated on the surface of the coated article. Then, the tube is placed on the surface of the coated article, heated and shrink-fixed, and further heated to a temperature higher than the melting point of the fluororesin constituting the primer and lower than the melting point of the tube. In this conventional configuration, a primer obtained by adding a surfactant and the above-mentioned fluororesin to an aqueous dispersion liquid comprising an aqueous solution is dispersed (dispersed into a water-soluble fluororesin particle).
Spraying), it is impossible to obtain a uniform, smooth and thick coating layer by means of this primer spray coating , and countless porous (pinholes) are formed.
Made is because, it is difficult to apply to those repetitive stress effects of high compression and decompression of multi-cycle, such as a spring member, even provisionally applied, a problem that cracks in the coating layer at an early stage is generated In addition, in order to form a coating layer using the above-described primer, it is necessary to apply and bake a plurality of times to the object to be coated, which not only increases the number of man-hours but also increases the processing cost. There is a problem in that air bubbles are mixed in and pinholes are formed after baking, and corrosion occurs from the pinholes.

SUMMARY OF THE INVENTION The present invention relates to a coupler.
Used for parts with chemical resistance such as pumps, valves, etc.
A resin-coated spring member to be partially covered with a PFA resin tube extending the entire outer surface of the spring body from the end of the spring body and a PTFE resin tube covering the entire outer surface of the tube. The entire spring can be reliably prevented from being corroded from the cracks that occur on the surface, and it can be used even under high temperature conditions. Its application temperature range is wide, and it has a double tube coating structure.
In addition, by securing sufficient thickness, defects such as pinholes
, Especially when repeated loads are applied and chemical resistance is required.
Greatly improves safety for spring members such as couplers
Excellent in stress crack resistance and flex life
An object of the present invention is to provide a very good resin-coated spring member.

The present invention provides a coupler,
Used for chemical resistant parts such as pumps and valves
In a resin-coated spring member, a PF in which the entire outer surface of a spring body formed of a metal wire is extended from an end of the spring body.
PF covered with A resin tube and covered with the spring body
After the outer surface of the A resin tube is double- coated with a PTFE resin tube having good heat shrinkability, the spring body is heat-treated at an appropriate temperature to form a coupler and a pump.
It is a resin-coated spring member used for a part having chemical resistance such as a pump and a valve .

According to the present invention, the resistance of couplers, pumps, valves, etc.
Resin-coated spring members used for parts with chemical properties
Then, a spring body formed of a metal wire is covered with a PFA resin tube extending from the spring body, and the outside of the spring body is double- coated with a PTFE resin tube. The PFA resin tube is welded and fixed to the spring body while keeping the tube shape ,
The PTFE resin tube coated on the outside is thermally shrunk to be integrally formed.

According to the present invention, the entire outer surface of the spring body constituting the resin-coated spring member is formed by the PFA resin tube and the PFA resin tube.
Since the PFA resin tube is double-coated with the TFE resin tube, the PFA resin tube is firmly welded and fixed to the spring body made of a metal wire, and the PFA resin tube and the PTFE resin tube are cracked by stress due to repeated compression and restoration. However, even if cracks occur, only the cracked portion needs to be corroded, and the entire spring can be reliably prevented from being corroded. Further, the PFA resin has a higher heat resistance temperature than the FEP resin and is excellent in stress crack resistance, so that it can be used even under high temperature conditions, and its applicable temperature range is widened. Further, under conditions where a repeated load is applied, the safety against breakage is greatly improved, and the PF
The PTFE resin tube has better chemical resistance than the A resin tube, and improves the chemical resistance with respect to a structure in which the entire spring is covered with only the PFA resin tube. Moreover, the present invention is coated by extending the PFA resin tube from resolver <br/> ne body end portion, such a metal wire, a heat-shrinkable PTFE resin tube constituting the outer tube, inner PFA
Utilizing the heat melting property of the resin tube, PF
A resin tube is melted as it is in the form of a tube, and at the same time, the sheath tube, the spring body and the tube end are welded by the shrinkage force of the shrinkage of the PTFE resin tube, and the melting point is similar to PTFE as the inner tube. Since PFA is selected and used, the heat shrinkability of PTFE can be fully exhibited, and a large shrink force can be obtained. Therefore, PTFE
In combination with the good weldability of PFA and PFA, it is possible to obtain a solid coating layer, and at the same time, it is also possible to form the tube end firmly.
There is no peeling between the resin coating portion and the spring body, and there is an effect that a spring member having high corrosion resistance can be obtained. Further, unlike a conventional primer, a tube is used, so that the number of manufacturing steps and manufacturing costs are increased. In addition to the reduction of the thickness, a sufficient thickness can be ensured, and there is an effect that defects such as pinholes do not occur. In particular, a double tube coating configuration as described above
Due to repeated loading, chemical resistance is required
For spring members such as couplers, pumps and valves,
Has greatly improved safety and has excellent stress rack resistance.
And the applicable temperature range has been expanded.
The resistance to stress cracking is very good.
There is a remarkable effect of significantly increasing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. The drawing shows a SUS coil spring made of PFA resin and PTFE resin as an example of a resin-coated spring member.
It indicates a resin-coated spring which is coated on heavy, in FIGS. 1 and 4, a resin-coated spring of the present onset Ming, for example, made of PFA resin to the entire outer surface of the coil spring 2 formed by winding a wire 2a made of SUS ( the coated tube 3 of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) thermally welded, integrally coated tube 4 of this made of PTFE resin was coated on the entire outer surface of the coating tube 3 (polytetrafluoroethylene) by heat shrinkage Molding.
When manufacturing the resin-coated spring 1 described above, as shown in FIGS. 2 and 3, a longitudinal end portion is formed in a substantially hemispherical shape on the entire outer surface of the coil spring 2 formed by winding a SUS wire 2a. A coating tube 3 made of PFA resin formed to have a hole diameter slightly larger than the outer diameter of the wire 2a is extended from one end side to cover the entire surface of the coating tube 3 covered with the coil spring 2. A coating tube 4 made of PTFE resin having good heat shrinkability and having a hole diameter slightly larger than the outer diameter of the coating tube 3 is coated from one end to form a double coating structure. Next, as shown in FIGS. 4 and 5, while the entire coil spring 2 is covered with a coating tube 3 made of PFA resin and a coating tube 4 made of PTFE resin, a suitable heating means such as a heating tool or a heating furnace is used. (Not shown) to heat the coating tube 3 at an appropriate temperature to cover the entire outer surface of the coil spring 2 with the coating tube 3.
The coated tubes 4 which were heat-welded in the form of a tube and which were coated on the outside were thermally shrunk,
The entire outer surface of the coil spring 2 is integrally molded in a state in which the entire outer surface of the coil spring 2 is double-coated with a coating tube 3 made of PFA resin and a coating tube 4 made of PTFE resin Can be. For the purpose of comparing the characteristics of the resin-coated spring 1 formed as described above , for example, as shown in Table 1, the conventional resin-coated spring 1
Resin (trade name = Teflon FEP1)
00-J and Teflon FEP140-J) were used.
And comparative, the onset Ming PFA resin used in the resin-coated spring 1 (trade name = Teflon PFA350-J) using
It manufactures and use the example of the invention, the flex life MI
Showing T-type tester (folding endurance test method) test results obtained on the same conditions by the following table 1.

[Table 1] As is clear from the above Table 1, the flex life value of the PFA resin used for the resin-coated spring 1 of the present invention is higher than that of the FEP resin used for the resin-coated spring 11 of the conventional product. A PFA resin having a higher value is more suitable for an application involving bending. In addition, since the fresh life value is an indicator of the stress crack resistance, it is clear that the PFA resin is more excellent in the stress crack resistance than the FEP resin. That is, the entire outer surface of the coil spring 2 constituting the resin-covered spring 1 is covered with the cover tube 3 made of PFA resin and the PT.
Since it is doubly covered with the coating tube 4 made of the FE resin, the coating tube 3 made of the PFA resin is firmly welded and fixed to the coil spring 2, and the coating tubes 3 and 3 are subjected to stress due to repeated compression and restoration. Even if a crack occurs in the coil spring 4, only the cracked portion needs to be corroded, and the entire coil spring 2 can be reliably prevented from being corroded. Further, the PF used for the resin-coated spring 1 of the present invention is higher than the heat-resistant temperature (melting point 270 ° C.) of the FEP resin used for the resin-coated spring 11 of the conventional product.
A resin has a higher heat-resistant temperature (melting point: 300 to 310 ° C.) and is more excellent in stress crack resistance, so that it can be used even under high temperature conditions, and its applicable temperature range is widened. Further, under conditions where a repeated load is applied, the safety against breakage is greatly improved, and the PF
The PTFE resin is more excellent in chemical resistance than the A resin, and the chemical resistance is improved as compared with the conventional configuration in which the entire outer surface of the coil spring 2 is simply covered with only the PFA resin coating tube. Moreover, in this embodiment, the PFA resin tube is extended from the end of the substantially hemispherical spring main body made of a metal wire and covered, and the heat shrinkability of the PTFE resin tube constituting the outer tube and the inner PFA resin tube are improved. Utilizing the heat melting property of PFA resin tube during heat treatment
Simultaneously with the melt remains tubular, there is configured by covering the tube with the spring body and tube ends welded contractile force due to shrinkage of the PTFE resin tube, selecting a PFA of PTFE and the melting point is approximated as the inner tube Since the PTFE is used, the heat shrinkability of PTFE can be fully exhibited, and a large shrink force can be obtained. Therefore, in combination with the good weldability of PTFE and PFA, a solid coating layer can be obtained, and at the same time, the tube end can be formed firmly. Since there is no peeling between the covering portion and the spring body, there is an effect that a spring member having high corrosion resistance can be obtained. Further, unlike the conventional primer, the structure uses a tube.
Not only the number of manufacturing steps and manufacturing cost can be reduced, but also a sufficient thickness can be ensured, and there is an effect that defects such as pinholes do not occur. In particular, as mentioned above
With a double tube coating configuration, repeated loading
Couplers, pumps, and valves that require chemical resistance
The safety of lubes and other spring members has been greatly improved.
It has excellent stress rack resistance and the applicable temperature range
As it becomes wider, the flex life is extremely good.
Sensible as a result, resistance to stress cracks is enhanced significantly the
Significant effect. In correspondence between the configuration of the present invention and the above-described embodiment, the resin-coated spring member of the present invention corresponds to the resin-coated spring 1 of the embodiment, and similarly, the spring body corresponds to the coil spring 2, The PFA resin tube corresponds to the covering tube 3, and the PTFE resin tube corresponds to the covering tube 4. However, the present invention is not limited to the configuration of the above-described embodiment. In the above embodiment, the entire outer surface of the coil spring 2 constituting the resin-coated spring 1 is made of a PFA resin-coated tube and PT.
Although it is double coated with a coating tube made of FE resin,
For example, a spring member such as a spiral spring, a leaf spring, a disc spring, or the like may be double-coated with each of the coating tubes 3 and 4, and is not limited to the coil spring 2 of the embodiment.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a resin-coated spring member of the present invention.

FIG. 2 is a longitudinal sectional view of a coil spring showing a state covered with a coating tube made of PFA resin.

FIG. 3 is a longitudinal sectional view of the coil spring showing a state where the coil spring is covered with a covering tube made of PTFE resin.

FIG. 4 is a longitudinal sectional view of a coil spring showing a state in which a coating tube made of PFA resin and PTFE resin is thermally welded.

FIG. 5 is a radial cross-sectional view of the coil spring showing a state in which a coating tube made of PFA resin and PTFE resin is thermally welded.

FIG. 6 is a longitudinal sectional view showing a conventional resin-coated spring.

FIG. 7 is a longitudinal sectional view showing another conventional resin-coated spring.

[Explanation of symbols]

 2: Coil spring 2a: Wire rod 3: Covered tube 4: Covered tube

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 15/08 102 B32B 15/08 102B B29K 27:12 105: 02 B29L 9:00 31:00

Claims (1)

(57) [Claims] 1. Chemical resistance of couplers, pumps, valves, etc.
In the resin-coated spring member used for the portion having the PF, a PF in which the entire outer surface of a spring main body formed of a metal wire material whose longitudinal end is substantially hemispherical is extended from the end of the spring main body.
PF covered with A resin tube and covered with the spring body
After double cover the entire outer surface of the A resin tube with a good PTFE resin tube having heat shrinkability, Karapu of was integrally molded by heat treatment by an appropriate temperature the spring body, Pong
A resin-coated spring member used for parts having chemical resistance, such as pumps and valves .