JPS60179590A - Pipe joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a pipe joint, and relates to a novel pipe in which a spring washer placed inside the joint is used to obtain a seal between a pipe to be connected and a pipe joint. It provides a joint.

BACKGROUND OF THE INVENTION Many types of fixed and mobile mechanical devices have internal fluid flow systems that utilize tubes to conduct gas or liquid. The components in such systems are typically
1 which is connected to these members by pipe joints.
They are connected to each other by one or more tubes. An example of the use of such connection pipes is in automobiles, where pipes are used to guide fuel, lubricating oil, cooling fluid, exhaust gas, and the like. Due to design and operating factors and manufacturing costs, tubing made from ductile metal materials or alloys is commonly used. Certain machines with piping systems for fluid communication1. Due to dimensional tolerances that occur during mass production of devices, the relative placement and distances between the tubing connections often vary. For this reason, often
It is necessary to use specially tailored fittings to connect the tubes by precisely engaging the ends of the tubes into the fittings. Such custom fittings allow the tube to be cut to the correct length so that the axis of the tube at the end is precisely aligned with the axis of the hole in the fitting to facilitate insertion of the end into the fitting. It requires cutting and proper bending. This problem is typically exacerbated when the ends of the tube are not parallel to each other. The need for specially tailored fittings to fit the pipes of a particular application increases the cost and length of manufacturing time for the mechanical device. In addition to the problems of precisely dimensioning the pipe to be connected in relation to the fitting as described above and precisely aligning the tube end with the fitting, it is also necessary to ensure proper engagement with the fitting. There is a problem in that residual stress exists in the piping structure due to the fact that the pipe must be deformed. Such residual stresses can predispose to fatigue failure when the tube is subjected to steady vibration or other stresses such as occur in automotive fluid flow systems. Therefore, instead of using special pipe joints, piping has been carried out using corrugated pipes or pipes made from materials with high elastic deformability, but such piping has its own unique characteristics in terms of cost and strength. Has disadvantages.

Problem to be solved Accordingly, without precisely dimensioning the length of the tube,
Also, without having to precisely align the pipe end with the pipe fitting,
It has been desired to develop a pipe joint that can sealingly engage a pipe, and the primary object of the present invention is to provide such a pipe joint.

In addition, there is a desire to develop a pipe joint that has a small number of parts and can be easily assembled, so this invention provides a pipe connection structure that has a small number of parts and is highly reliable and inexpensive even for inexperienced personnel. Another challenge is to provide a new pipe joint that can do this.

Technical Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a new spring washer compression type pipe joint that uses a truncated conical spring washer. be. The spring washer is compressed along its axial direction by the tightening of the two joint elements that are fastened to each other, and as a result, the inner edge of the washer overflows in the radial direction and contracts, sealingly engaging the pipe. It will be installed as follows. The pipe joint according to the present invention is configured to have a hole inside thereof with a diameter exceeding the outer diameter of the pipe to be connected, and the pipe joint can be inserted within the range that the hole allows for the pipe to be inserted with a margin. It is possible to arrange the tube by shifting the axis so that the axis of the tube intersects with the axis.

The hole in a pipe joint can be formed to have a length that allows the insertion length of the pipe to be changed within a range when viewed in the axial direction of the joint, and by forming the hole in this way, it is possible to create a hole with a precise length for the pipe to be connected. will not be required.

The second invention proposes a pipe joint that uses a pair of spring washers as a pipe joint that requires a greater degree of sealing between the pipe and the pipe to be connected. The pair of frusto-conical spring washers is connected between the two joint elements which are fixedly tightened together, and the ends of the inner edges or the outer edges of the washers are J-touched to each other. When the circumferential joint elements are tightened, the inner edges of both washers engage with the tube, thereby increasing the degree of sealing.

Hereinafter, the present invention will be described in detail with reference to the drawings. Embodiment A spring washer compression type pipe joint according to the present invention is shown in FIG. This pipe joint 10 includes a first joint element 12 having a male thread forming portion 14f and constituting a joint body, and can be adopted in a joint portion where a conventional pipe joint is commonly used. ing. The first coupling element further has an externally threaded portion 16 . External thread forming part 14 and external thread forming part 1
A radially projecting flange portion 18 is provided between the flange portion 6 and the flange portion 6, and the flange portion 18 has a large square outer surface so that the joint element 12 can be assembled using a conventional tool. is desirable. The first coupling element 12 has a hole 20, which has a first inner diameter section 22. i2 inner diameter part 2
4 and a shoulder portion 26 extending in the radial direction between these portions 22,24.

Two significant features of the invention are that the diameter of the second inner diameter portion 24 of the bore 20 is sized to exceed the outer diameter of the pipe to which it is connected, indicated at 28; This allows an arrangement with no offset or intersection between the longitudinal axes of the tube 28 and the bore 20. The diameter of the second inner diameter portion 24 is preferably greater than the outer diameter of the tube 28 by an amount sufficient to provide an intersection of about 50 degrees between the axes mentioned above. Angle A shown in FIG. 1 represents such a crossing angle.

Another significant feature of the invention is that the axial length of the second inner diameter portion 24 is such that the tube 28 can be inserted into the bore 20 a sufficient length. 1/2
For inch (about 1.27 cx) diameter tubing, an insertion length of at least 1/8 inch (about 0.320), preferably about 1/2 inch (about 1.27 am) is obtained. , it is desirable to set the above-mentioned axial length.

The first coupling element 12 also has one flat end surface 32 at the end of the externally threaded portion 16 lying in a plane perpendicular to the longitudinal axis 30 of the borehole 20 .

The first coupling element 12 constituting the coupling body can also have a shape different from that shown.

For example, when the pipe joint is formed integrally with another structure, the male thread forming portion 14 can be omitted. In addition, in the case of a pipe joint for connecting two pipes, the first joint element 1
A structure corresponding to 2 is given.

Tube 28 is preferably a conventional thin-walled tube, typically formed from a ductile metal. The tube 28 may also be made of other materials, such as plastic.

The only difference in the material for the tube 28 is that the tube 28 made of the same material can be deformed into a radially inward circular shape, which will be described later.

The pipe fitting 10 also includes a second fitting element 34, which is a nut, and the second fitting element 34 has an inner threaded portion threaded onto the outer threaded portion 16 of the first fitting element 12, which is the fitting body. It has a threaded portion 36. The second coupling element 34 preferably has a hexagonal outer surface 38 to facilitate tightening using conventional tools, and includes a radially inwardly projecting lip portion 40. This flange portion 40 has a flat inner surface 42 lying on a plane perpendicular to the axis 30, similar to the one end surface 32 of the first coupling element 12 described above. Flange portion 40 also has a through hole 44 having a diameter larger than the outside diameter of tube 28 . To accommodate the aforementioned off-axis arrangement between the tube 28 and the second inner diameter portion 24, the bore 44 described above may be tapered as shown.

Pipe fitting 10 further includes a spring washer 46 disposed between second coupling element 34 and first coupling element 12 . In the undeformed state where this spring washer 46 is not subjected to compression,
It is curved as shown in Figure 3. As can be clearly seen in FIG. 3, the spring washer 461 is formed into a frusto-conical shape having an outer edge 48 and an inner edge 50.

Although the shape of the outer end edge 48 does not need to be M-tight, it is desirable that the inner end surface 50 be machined to form a cylindrical surface centered on the axis of the spring washer 46. Angle B shown in FIG. 3 is the bevel angle of spring washer 46 measured between straight lines 56 and 58 drawn along the surface of spring washer 46 on a plane passing through axis 60 of spring washer 46. The diameter of the outer edge 48 is dimensioned such that the spring washer 46 remains inserted and installed within the second coupling element 34 without interfering with the internally threaded portion 36 under any conditions.

The inner edge 50 of the spring washer 46 is sized to receive the tube 28 without interference, but the inner edge 50 of the spring washer 46 is sized to receive the tube 28 without interference.
For example, the air gap between 3/1000-5/1000 inches (
It is desirable that the dimensions be such that it has an extremely small value, such as approximately 0.076-0.127 mm. If the above-mentioned gap is large, the degree of compression of the tube 28 by the spring washer 46 is limited, and the seal L between the spring washer 46 and the tube 28 is reduced.
A significant loss of sealing properties can occur especially when off-axis connections are made. Spring washer 46 is preferably formed from spring steel or high yield point stainless steel (if corrosion problems are anticipated).

The joint element 34 of the nut and the name 2 is the inner surface 42 described above.
and one end surface 32 contact each other, or both surfaces 42, 32
The spring washer 46 is formed to be threadedly engaged with the first joint element 12, which is the joint body, until the distance between the spring washers 46 and the spring washer 46 is smaller than the thickness of the spring washer 46.

FIG. 1 shows a pipe joint 10 which has been assembled with a spring washer 46 disposed between the surface 32 and inner surface 42 of the bell 11 described above. This FIG. 1 illustrates the pipe fitting 10 in a state W in which the spring washer 46 has not undergone any deformation. In this state, the tube 28 can be inserted into the hole 20 of the first coupling element 12.

The degree of insertion of the tube 28 into the hole 20 does not need to be set precisely, and the tube end 52 on the side of the pipe fitting 10 can be changed to any position within the range of X shown in FIG. No problem. Since the insertion depth of the tube 28 can be changed within this range, the length of the tube 28 does not need to be set precisely.

Furthermore, since a gap is secured between the pipe 28, the first joint, and the element 12, the 11I111 line misalignment between the pipe 28 and the pipe joint 10 is accommodated, and between the structures that are mutually read by the pipe 28. There is no need to precisely set the degree of alignment and spacing. 81
The position of the pipe 28 indicated by the chain line in the figure is the position of the pipe 28 and the pipe fitting 1.
0 are arranged with their axes shifted from each other.

The second (2) shows a state in which the pipe joint 12 is completely tightened. By tightening the second coupling element 34, which is a nut, onto the first coupling element 12, which is the coupling body, the spring washer 46 is compressed in the axial direction between the one end surface 32 marked 1111 and the inner surface 42. receive. Such compression causes the inner edge 50 of the spring washer 460 to contract radially, creating a localized circular compression of the tube 28. Due to the compression of the tube 28 by this spring washer 46, the tube 2
8 causes the tube 28 and the spring washer 4 to
A fluid-tight contact is obtained between the two. The bevel angle B of the spring washer 46 is set so that the inner edge 50 thereof contracts in the radial direction to a desired extent. During the development of the present invention, it was found that excellent results are obtained when the angle iB is approximately 110°. Second fitting oxygen 34
is tightened against the first coupling element 12 until the spring washer 46 is flat or nearly flat (i.e., until the angle B is approximately 180°), so that the spring washer 46 is attached to the one end face 32 described above. and inner surface 42 to create a seal. Since the annular gap exists on the outer circumferential side of the spring washer 46, the washer 46 is compressed even when it is eccentrically positioned 1ffi with respect to the first joint element 12. 1st
When tightening the second coupling element 34 against the stray element 12, the torque required to rotate the second coupling element 34''fc, which is a nut, reaches the state shown in FIG. When the second coupling element 34 is tightened to the desired degree, the operator can easily know that the second coupling element 34 has been tightened to the required degree.

FIG. 1 shows a spring washer 46 in the pipe fitting 10, with the outer edge 48 of the washer 46 facing one end surface 32 of the first fitting element 12 before deformation.
Although the spring washer 46 is shown assembled in such a way that it is in contact with the spring washer 46, the direction of the spring washer 46 is reversed and the outer edge 4 of the washer 46 is removed before deformation.
8 can also be installed in such a way that it contacts the inner surface 42 of the second coupling element 34.

The spring washer 46 can be assembled in either orientation, with one end surface 32 of the first coupling element 12 and the inner surface 4 of the second coupling element 34.
This is possible because both 2 and 2 are flat.

In order to permit installation of the spring washer 46 in either orientation, the hole diameters of both coupling elements 12.34 are such that the spring washer 46 will not displace the spring washer when tightened on the fitting 10, regardless of the orientation of the spring washer 46. The settings are such that 46 axial compressions are achieved. In applications where it is desired to reduce the threading stress acting on the tube 28 during threading of the second coupling element 34, which is a nut, the spring washer 46
It is preferable to incorporate it in the orientation shown in FIGS. 1 and 2. This is because the spring washer 46 and the non-rotating body (first joint element 12)
This is because the contact radius between the spring washer 46 and the rotating body (second coupling element 34) is larger than the contact radius between the spring washer 46 and the rotating body (second coupling element 34).

FIG. 4 shows a pipe joint according to a second embodiment of the present invention, indicated generally by the reference numeral 10'.

This embodiment differs from that shown in FIG. 1.2 only in that a pair of spring washers 46 is provided instead of a single spring washer. As shown in FIG.
0' so that the ends of the tabs υ on the inner edge 50 side are in contact with each other in opposite directions. The fitting 10' shown in FIG. 4, when tightened, provides a greater degree of sealing engagement with the outer circumferential surface of the tube 28. This embodiment is suitable for use when a higher degree of sealing is required or when a higher force is required to cause compressive deformation of the tube 28.
It has become desirable. 1 as in this example
When providing the pair of spring washers 46, the pair of spring washers 46 may be arranged such that their ends on the outer edge 48 side are in contact with each other, which is different from the case shown in the first drawing. In the structure according to the second embodiment, the length of the internally threaded portion 36 of the second coupling element 34, which is a nut, must be increased to accommodate the additional spring washer 46t.

Effects of the Invention The pipe joint of the present invention has one end surface (on the first joint element) and an inner surface (on the first joint element) located opposite to each other in the joint axial direction on the first and second joint elements that are fixedly tightened together. (2) on the coupling element), and then a truncated conical spring washer having an opening with a diameter slightly larger than the outside diameter of the pipe to be connected is placed between such two surfaces. The spring washer is compressed between the two surfaces by tightening between the inner joint elements, and sealingly engages the two surfaces, and the inner edge of the washer contracts due to the compression to seal the pipe to be connected. conversely, the hole in the inner fitting element into which the pipe to be connected is inserted has enough room to insert the pipe to be connected. It can be, and is actually, made to have a diameter like that. The tube can therefore be tilted relative to the tube fitting within the range permitted by the bore of the inner fitting element, so that precise alignment of the tube end of the tube to be connected with respect to the tube fitting is no longer necessary.

Furthermore, since the spring washer placed between one end surface of the first joint element and the inner surface of the second joint element fixes the pipe and seals between the pipe and the joint, the first joint element There are no restrictions on increasing the axial length of the hole in the first joint element, and there is no problem even if a large pipe is inserted into the hole. As long as the length t of the pipe to be connected is set, there is no need to precisely dimension the pipe to be connected.

Furthermore, since the pipe joint of the present invention is constructed by combining two joint elements that are fixedly tightened together and one or two spring washers, the number of parts is small, and the number of parts between the inner joint elements is small. The pipe connection operation can be easily performed because the pipe can be connected and the required seal can be obtained by tightening the pipe.

When a pair of spring washers is provided according to the second invention, the inner edges of the two spring washers engage with the pipe to be connected, so that the degree of sealing between the pipe joint and the pipe is improved. Also, when the pipe is not susceptible to deformation due to compression, the large tightening applied to compress the two spring washers in the axial direction will cause the pipe to undergo deformation through the spring washers due to the force. 0,'The inner edge of the spring washer is held to the tube at the deformed portion to improve the degree of sealing.4.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing the spring washer compression type pipe fitting according to this invention together with the pipe to be connected, in a state where the spring washer is not compressed and is not aligned with the pipe joint. The tubes arranged in the figure are shown in dashed lines. FIG. 2 shows the pipe fitting shown in FIG. 1 by tightening the fitting and compressing the spring washer in the axial direction to form a sealing engagement between the fitting and the pipe to be connected. It is a longitudinal cross-sectional view drawn in the obtained state. FIG. 3 is a partially cutaway perspective view of a spring washer provided in the pipe joint shown in FIG. 1.2. FIG. 4 is a longitudinal cross-sectional view showing another example of the pipe joint according to the present invention, in which a pair of spring washers are provided in a converging state. 10111]'... Pipe joint, 12... First coupling element, 16... External thread forming portion, 20... Hole, 24...
...Second inner diameter portion, 28...Pipe, 32...One end surface, 34...Second joint element, 36...Inner thread forming portion, 42...Inner surface, 44... Through hole, 46... Spring washer, 50... Inner edge.

Claims (1)

[Scope of Claims] 1. A pipe joint, which includes: (a) a first joint element having a hole therein that opens at one end surface, into which the pipe to be connected can be inserted with a margin; a first coupling element having a diameter; (b) A second joint element having an inner surface facing one end surface of the first joint element described above when viewed in the axial direction of the pipe joint, through which a pipe to be connected can be inserted with a sufficient margin. a second coupling element forming a through hole of a certain diameter;
(C) A truncated conical spring washer disposed between one end surface of the above-described first joint element and the bare inner surface of the above-described second joint, the spring washer having an outer diameter of the pipe to be connected. (d) a spring washer having an opening with a slightly larger diameter in its center; and the spring washer is compressed between the one end surface and the inner surface to seal the second joint element relative to the first joint element when viewed in the axial direction of the pipe joint. a tightening means for positioning the inner edge of the washer to contract and sealingly engage the pipe to be connected as a result of the compression;
Pipe fitting with. 2. The pipe joint according to claim 1, wherein the tightening means is a threaded portion formed on each of the first and second joint elements and screwed into each other. Fittings. aQ! The pipe joint according to item 1, wherein the spring washer has a groove angle of approximately 1100 degrees. 4. The pipe joint according to claim 1 (wherein the hole of the first joint element and the through hole of the second joint element should each be connected to the axis of the pipe joint. Pipe joint 05. A pipe joint formed to have a diameter that allows the axis of the pipe to be tilted up to a maximum angle of 5 degrees. (a) A pipe joint with an internal hole for IJ rolling on one end surface. (b) the above-mentioned joint element when viewed in the axial direction of the pipe joint; A second joint element having an inner surface facing one end surface of the first joint element, the second joint element forming a through hole having a diameter that allows insertion with sufficient clearance on the pipe to be connected. and (C), disposed between one end surface of the above-mentioned first joint element and the inward direction of the above-mentioned second joint element, with their inner edges or outer edges in contact with each other. a pair of frusto-conical spring washers, each of which has an opening at its center mK having a diameter slightly larger than the outer diameter of the pipe to be connected; (d); The tightening means formed on the first and second coupling elements described above and tightening or fixing the two coupling elements is a coupling element whose second longitudinal diameter is ml when viewed in the axial direction of the pipe coupling. Relative to this, the above-mentioned pair of spring washers receive pressure mk between the above-mentioned one end surface and the inward direction, and sealingly engage with said both surfaces, and the inner end edges of both washers contract due to the compression. 6. A pipe fitting that is positioned so as to engage in a sealing manner with respect to the pipe to which it is to be connected. and the RN tightening means is a pipe joint in which the means are threaded portions formed on the first and second joint elements and threadedly engaged with each other.7. The pipe fitting described above,
...The angle angle of each of the pair of spring washers described above is approximately 110.
° Pipe fitting O s, ta! j. The pipe joint according to claim 5, wherein the hole of the first joint element and the through hole of the second joint element are respectively connected to the pipe to be connected to the axis of the pipe joint. A pipe fitting that is formed to have a completely blind diameter that allows the axis of the pipe to be tilted up to an angle of approximately 5°.