Pipe joints or couplings – With assembly means or feature – Particular tool-engaging means or with tool
Reexamination Certificate
2000-08-03
2001-11-06
Nicholson, Eric K. (Department: 3627)
Pipe joints or couplings
With assembly means or feature
Particular tool-engaging means or with tool
C285S340000, C285S308000, C285S322000
Reexamination Certificate
active
06312019
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a quick-type pipe joint used for connection between various kinds of fluid pressure apparatus and a tube mainly in an air pressure circuit.
PRIOR ART
Conventionally, a quick-type pipe joint for use in an air pressure circuit is known in which a cylindrical joint body for housing a tube holding mechanism is made of a metal material. This joint body typically includes a fluid passage that penetrates through the inside thereof; a housing for housing a sealing member and an enlarged diameter recess for housing the aforesaid tube holding mechanism are disposed at one end of the fluid passage; and they are made of a cut product of a metal material made of brass or the like.
However, in the joint body made of the aforesaid cut product of the metal material, the surface roughness on the inner surface of the housing for sealing member does not necessarily reach a value suitable for sealing and, in some cases, air may possibly leak out, though only slightly, between the sealing member and the aforesaid inner surface of the housing of the joint body. Also, in a joint body made of a cut product, assembly may possibly end in a state in which cutting dusts produced at the processing time keep adhering to the inner surface of the housing for sealing member, whereby a defective product with incomplete sealing may be produced even though the processing is carried out appropriately.
Further, in the aforesaid conventional pipe joint, it is usually the case that a guide member made of synthetic resin is snap-fit onto the inside of the joint body made of the metal material. In this case, the strength of the pipe joint is largely dominated by the temperature characteristics of the guide member made of the synthetic resin, so that there have been strong desires for improvements in strength, thermal characteristics, and durability in various application fields.
SUMMARY OF THE INVENTION
The present invention has been made in order to solve these problems, and a technical object thereof is to provide a pipe joint in which a simple means further improves the sealing performance produced by an elastic sealing member housed in a joint body.
Another technical object of the present invention is to provide a pipe joint with improved assembling property of the elastic sealing member and improved air-tightness by using a joint body formed with improved surface roughness of the inner surface to be more suitable as a sealing surface.
Another technical object of the present invention is to provide a pipe joint with improved strength, thermal characteristics, and durability.
In order to achieve the aforesaid objects, a pipe joint of the present invention is characterized in that a joint body includes a fluid passage that penetrates through the inside thereof; at one end of the fluid passage in said joint body, there is disposed an enlarged diameter recess in which the inner rear side thereof is made into a housing for sealing member and the mouth side thereof is made into a housing for tube holding mechanism having an engaging groove for the tube holding mechanism; an attachment to a fluid pressure apparatus is disposed on an outer circumference of the other end of the joint body; the joint body having this construction is constructed as a cold-forged component of a metal material; the elastic sealing member for sealing between the inner surface of said housing for sealing member and the outer surface of the tube inserted through the tube holding mechanism is housed in said housing for sealing member; and a portion of the tube holding mechanism is elastically engaged in a slip-resistant state with the engaging groove of said housing for tube holding mechanism.
The pipe joint having the aforesaid construction can be used in the same manner as a conventional pipe joint. However, since the joint body in which the inner rear side of the enlarged diameter recess disposed at one end of the fluid passage is made into a housing for the elastic sealing member is constructed as a cold-forged component of a metal material, it is possible to obtain a joint body having an improved surface roughness easily as compared with a case in which the joint body is made by a cutting process or the like case. In particular, the surface roughness of the aforesaid housing for the elastic sealing member is improved, and its variation is stabilized, so that the sealing between the elastic sealing member and the inner surface of the housing can be made stable and more certain, and the sealing performance produced by the elastic sealing member can be improved.
Furthermore, there is no generation of contaminants at the time of molding the joint body, such as generation of cutting dusts accompanying the cutting or the like. Therefore, it is possible to avoid the case in which the air-tightness is hindered by adhesion of such contaminants to the inner surface of the housing for the elastic sealing member, and the cause of poor air-tightness is removed, whereby the assemblage will be easy and the quality of the product can be heightened.
In the aforesaid pipe joint, it is effective for improvement of performance if an engaging section having a sharp edge at its tip end is formed by outwardly folding an inner end side turnup section of a guide member made of a springy metal material disposed on an outer circumferential side of the tube holding mechanism; said engaging section is elastically engaged in a slip-resistant state with the engaging groove disposed in the housing for tube holding mechanism; a guide section for guiding a release bush used for releasing the inserted tube is made by inwardly folding the outer end of a cylindrical guide member located on the mouth side of the enlarged diameter recess; a projection which is in contact with an inner circumference of the enlarged diameter recess of the joint body is formed by outwardly folding an outer circumferential portion thereof to protrude; and the aforesaid guide section for guiding the release bush, the aforesaid projection, and the aforesaid engaging section on the inner end side of the guide member are formed by pressing a metal plate material.
Thus, if the guide member disposed on the outer circumferential side of the tube holding mechanism is constructed with a springy metal material and pressed into the aforesaid joint body, and the sharp edge at the tip end of the engaging section which edge is formed by folding the inner end side turnup section of the guide member is elastically engaged in a slip-resistant state with the engaging groove of the joint body, then a pipe joint with improved strength, thermal characteristics, and durability can be obtained because both are made of metal and, therefore, the influence of the temperature on their joining strength is small.
Further, by forming the aforesaid guide section of the guide member for guiding the release bush, the aforesaid projection, and the aforesaid engaging section on the inner end side of the guide member are formed by pressing a metal plate material and by disposing the guide member to allow the projection to be in contact with the inner circumference of the enlarged diameter recess of the joint body, the tube holding mechanism can be positioned stably in the enlarged diameter recess, the rigidity of the product itself increases, and the resistance to the rocking of the guide member is improved, so that air-tightness and durability against rocking of the tube and vibration of the joint body can be improved.
Moreover, this guide member can be made into a simple and multifunctional component, and a stable state of being mounted on the joint body can be ensured.
REFERENCES:
patent: 4645246 (1987-02-01), Guest
patent: 4796924 (1989-01-01), Kosugi et al.
patent: 4890865 (1990-01-01), Hosono et al.
patent: 4919457 (1990-04-01), Moretti
patent: 5085472 (1992-02-01), Guest
patent: 5681062 (1997-10-01), Fukao et al.
patent: 5762380 (1998-06-01), Hiwatashi et al.
patent: 378035 (1990-07-01), None
patent: 2060106 (1981-04-01), None
patent: 1602077 (1981-11-01), None
patent: 23
Mori Shizuo
Nakazumi Masahiro
Nicholson Eric K.
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
SMC Corporation
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