JP7549351B2 - Universal joint for fluid passage - Google Patents

Description

The present invention relates to a universal pipe joint for fluid piping that is used when connecting various pipes used as fluid passages, and more specifically, to a universal pipe joint for fluid passages that can easily adjust and set the delicate setting angles required at various connection points of pipes that serve as passages for various fluid flows made of liquids, and that has high joint strength, is highly flexible, and has excellent earthquake resistance.

Conventionally, there are two types of ventilation equipment for indoor ventilation: a direct-attached type that is attached directly to an opening in the wall of a building, and a stationary type that is installed on the inside of a ceiling or wall. In recent years, the stationary type has become mainstream. This stationary type ventilation equipment is connected to an external exhaust port attached to the wall of the building using an integrally formed elbow pipe or bellows pipe.

In other words, depending on the opening direction of the connection exhaust port on the installed type ventilation device, the connection direction between the connection exhaust port and the external exhaust port may be misaligned and not match due to factors such as the mounting position of the external exhaust port relative to the wall. In this case, the connection exhaust port and the external exhaust port are connected using either an elbow pipe, a bellows pipe, or a combination of an elbow pipe and a bellows pipe.

By the way, elbow pipes are effective as pipe joints for indoor ventilation because there are no irregularities on the inner surface that would hinder the flow of air, but since they are pipe joints with a fixed bending angle such as 90°, depending on the misalignment of the connection direction (misalignment angle), not only can the task be very difficult, but there are also cases where the elbow pipe alone cannot handle the job. In such cases, it is often combined with a bellows pipe, which has the flexibility to be freely oriented, or a bellows pipe alone is used.
In this way, the bellows pipe can be said to be an effective piping joint for such connections because it can be adjusted freely and smoothly to accommodate misalignment in the connection direction between the connection exhaust port and the external exhaust port. However, the bellows pipe has a problem in that the smooth flow of indoor air cannot be expected because of the presence of small irregularities on the inner surface of the pipe, such as high ventilation resistance.
In particular, when a bellows pipe is used as the external piping of a range hood that exhausts polluted air generated during cooking outdoors, the grease contained in the polluted air will repeatedly collide with the fine protrusions, causing the grease to easily accumulate inside the pipe, which is undesirable from the standpoint of fire safety.

On the other hand, in ordinary houses and high-rise buildings, domestic wastewater, like exhaust fluids, is installed by arranging pipes for said fluids in the narrow spaces between the walls and exterior walls of the building and between the floor and ceiling. However, in order to reduce construction costs, the space for said piping is generally limited to extremely narrow passages or spaces. Therefore, in such extremely narrow spaces, it is required to have a certain gradient as stipulated by the Building Standards Act, for example. At the same time, there is a problem in that the connection angle of the pipes must be arbitrarily changed and connected in relation to the installation of the pipes.
This work is extremely hard even for experienced workers, and it makes the work more complicated and prolonged, resulting in delays in delivery and significant increases in costs, making it uneconomical.

In order to solve this problem, conventionally there are bent tubular bodies called elbow pipes that are integrally molded from synthetic resin, but the bending angles of these elbow pipes are limited to a number of pre-defined specific angles, such as 45 degrees, 75 degrees, 90 degrees, and 180 degrees, which are manufactured by each manufacturer. However, all of these elbow pipes only have a fixed angle specified by the manufacturer, and therefore no matter how these are combined, it is impossible to set the bending angle of the connected pipe to any angle. Furthermore, even if multiple elbow pipes are combined to achieve a specified bending angle, a considerable amount of space is required around the group including the elbow pipe at the connection part, so that it is practically impossible to combine such multiple elbow pipes to set a specified gradient or angle within the already set narrow piping layer part.

In addition, there are universal elbow pipe joints, for example made of PVC resin, that are designed to allow the connection angle of two adjacent straight pipes to be changed by interposing a joint section that utilizes a spherical surface in part. However, the connectable bending angle of the two straight pipes to be connected in such universal elbow pipe joints is at most about 10 to 20 degrees, so that their practical value is essentially negligible.
Therefore, in the past, it was impossible to realize the gradient stipulated by the Building Standards Act in all of the piping layers, and as a result, a significant portion of the fluid piping sections were not set to the specified gradient, and in some cases were arranged in a roughly parallel state in many locations. As a result, in such detached houses and high-rise buildings, it was necessary to clean the inside of the fluid piping sections at least once a year using a high-pressure washer, etc., which resulted in a major drawback of high management and maintenance costs.

Alternatively, there are a number of cases in which straight pipes of a specified length are forcibly bent within the pipe connection processing space to conceal the appearance that the pipes have been connected to a specified gradient. Such improper pipe connection processing naturally results in material being retained within the pipes or excessive loads being applied to the pipes for long periods of time, resulting in a major social problem of a significant deterioration in the durability of the piping system.
This relationship applies not only to the piping inside the detached house or high-rise building, but also when domestic wastewater discharged from the detached house or high-rise building is connected to the main sewer pipe buried under the road, etc., and the same problem is occurring at multiple connection points installed in multiple piping sections that lead from the underground part of the detached house or high-rise building to the main sewer pipe.

Furthermore, in the connection of the piping sections using conventional elbow pipes, the elbow pipe section and the straight pipe section that is joined to it are simply fitted together, and the structure has no flexibility, so the connection strength is low. If a large vibration such as an earthquake is applied, the fitting parts of the two may be destroyed or come apart, and in some cases, necessary gas or fluid may leak to the outside, creating a risk of a secondary disaster.
Furthermore, the above-mentioned universal elbow pipe joint also has a problem in that the angle adjustment change is small and the degree of overlap of the mating parts at the joint part including the spherical surface is small, so that it cannot fully absorb vibrations caused by earthquakes, etc., and the pipe joint part can easily be destroyed.

As an example of a method for solving the above-mentioned conventional problems, a technical idea has been proposed that aims to solve the technical drawbacks by improving the structure of the above-mentioned universal elbow pipe joint.
For example, Japanese Patent Laid-Open Publication No. 07-265973 (Patent Document 1) discloses a universal joint having a structure in which one of the first and second straight pipe sections can swivel at a slight angle relative to the other straight pipe section due to the inner spherical body being smoothly joined to the second straight pipe section, and a first connecting structure consisting of a first fitting portion made up of a first straight pipe section and an inner spherical body connected to one end of the first straight pipe section, and a second connecting structure consisting of a second straight pipe section and an outer spherical body connected to one end of the second straight pipe section and fitting onto the outer peripheral surface of the inner spherical body, and the first and second straight pipe sections can swivel at a slight angle relative to the other straight pipe section due to the inner spherical body and the outer spherical body being smoothly joined to each other.

However, Patent Document 1 merely discloses a universal joint in which the first straight pipe section joined to the inner spherical body is configured to rotate around an appropriate axis passing through the center point of the inner spherical body within a range inclined at an angle of only 30 degrees. With this configuration, it is impossible to connect at least two straight pipe sections to be connected with a large degree of freedom in the bending angle, and since it can only be used as a connecting joint for a very limited number of purposes, it has little practical use.

On the other hand, Japanese Patent Application Laid-Open No. 2010-242880 (Patent Document 2) discloses a universal joint having a configuration substantially identical to that of the universal joint of Patent Document 1 above, but the feature of Patent Document 2 is that the shapes of the opening edge portions of the inner and outer spherical bodies that are slidably fitted together are set to a specific shape in order to expand the range of connection angles between the two straight pipe sections to be connected in the universal joint of Patent Document 1 above.

That is, as shown in FIG. 3 of the same patent document 2, the shape of the opening edge of the inner spherical body is determined on a reference plane formed by a straight line X connecting the center point P of the inner spherical body and the central axis Z of the straight pipe portion, which is located eccentrically from the center point P, and an intersecting straight line Y that passes through the center point P of the inner spherical body and is perpendicular to the plane formed by the spherical center point P and the central axis Z of the straight pipe portion, from the point where one end side of the straight line X, which is located within the reference plane, intersects with the opening edge of the inner spherical body, to the point where the other end side of the straight line X intersects with another end side of the opening edge of the inner spherical body. The outer sphere is designed so that the sense of distance from the reference plane gradually increases as it reaches the point where it intersects with the reference plane, while the shape of the opening edge of the outer sphere is formed to have an opening shape that follows the reference plane, as shown in FIG. 5 of the same patent document 2. It is described that by adopting this configuration, the shape of the opening edge of the inner sphere has a larger inclination angle than the shape of the opening edge of a conventional inner sphere, making it possible to set the bending angle between the connecting straight pipe sections with more freedom.

However, the technical explanation disclosed in Patent Document 2 does not clarify the setting conditions of the reference plane, and therefore does not specify the location of the reference plane or its inclination angle with respect to the horizontal plane, etc., and merely indicates an impracticable state.
In other words, in the above configuration, although it is defined that "a straight line X connects the center point P of the inner spherical body and the central axis Z of the straight pipe section," an infinite number of straight lines X can exist within the plane formed by the spherical center point P and the central axis Z of the straight pipe section, and with this technical explanation as it is, it is impossible to specify the position and shape of the reference plane.
However, in another specific example in Patent Document 2, it is disclosed that the straight line X can be set so that the angle between the straight line X and a straight line W drawn from the center point P of the sphere at a right angle to the central axis Z of the straight pipe portion is 26 degrees or 34 degrees in the plane formed by the center point P of the sphere and the central axis Z of the straight pipe portion. If this configuration is an essential constituent element of the invention, the industrial implementation of the invention will be guaranteed. However, unless this is the case, the invention in Patent Document 2 merely discloses an invention that cannot be implemented, and it must be said that it cannot become a publicly known example that is effective for any later invention.

Furthermore, even if we were to concede and accept that the invention of Patent Document 2 exists only in the above specific example, the shape of the opening edge of the outer spherical body does not specify at all what height the inclined wall, i.e., the auxiliary sliding part, should be formed with respect to the reference plane that is formed at a slight angle to the horizontal plane, and no specific example is disclosed in relation to this. Therefore, even a person skilled in the art would not be able to manufacture an industrially usable universal joint from the invention of Patent Document 2. In other words, Patent Document 2 does not contain any technical suggestions that would enable the creation of a new and inventive technical configuration that is necessary to avoid the above-mentioned problems of the prior art.

Furthermore, the shape of the opening edge of the outer spherical body in Patent Document 2 is formed by extending an oblique auxiliary member with an unclear range from the reference plane, and the shape of the opening edge of the inner spherical body is simply arranged and formed on the same plane as the reference plane in the same manner as in the prior art. Therefore, the area, length, etc. of the portion where the opening edge of the outer spherical body and the opening edge of the inner spherical body overlap and fit together is not found to be significantly larger than in the prior art, and there is no evidence that the bending angle formed between the two connected straight parts is larger than in the prior art, and there is no clear guarantee of this.

Furthermore, in Patent Document 2, since the overlapping engagement area between the opening edge of the outer spherical body and the opening edge of the inner spherical body is not set significantly larger than in the prior art, it is inevitable to conclude that the strength of the connection part of the universal joint remains weak and, at the same time, there is a high risk that it will easily separate or be destroyed by vibrations such as those caused by earthquakes.
In other words, neither Patent Document 1 nor Patent Document 2 discloses any technical information necessary to solve the problems of the prior art, nor is there any description that suggests such a thing.
On the other hand, in Japanese Utility Model Application Laid-Open Publication No. 01-069990 (Patent Document 3), in a pipe joint in which a pair of spherical portions are fitted together, a pair of half-split ring members are used to reinforce the fitting portion of the spherical portions, and the strength of said portion is reinforced by utilizing the tightening force of screws. However, with this configuration, since both straight pipe portions cannot bend or rotate freely relative to each other, it is completely impossible to easily correct slight misalignment between the central axes of the front and rear pipes during piping installation work, and the pipe joint is simply unable to absorb vibrations from earthquakes, etc., and has a structure that makes it easily destroyed.

On the other hand, JP 2015-124510 A (Patent Document 4) discloses a structure in which a pipe joint in which a pair of spherical parts are fitted together uses a pressing member having an annular ring shape to reinforce the fitting area of the spherical parts, and by fitting an inclined hole formed on the side of the pressing member into a protrusion provided on the outer peripheral surface of the periphery of one of the spherical parts and rotating the pressing member, the pair of spherical parts are pressed together, thereby increasing the strength and fixing the joint. However, in a pipe joint with this structure, when the pressing member is loosened, the pair of spheres can certainly rotate and slide relative to each other freely, but after the pressing member is operated, the pair of spheres are configured to be in a state where they cannot move, rotate, or rotate relative to each other at all, and there is no function to absorb shaking from earthquakes, etc.

Japanese Patent Application Publication No. 07-265973 JP 2010-242880 A Japanese Utility Model Application Publication No. 01-069990 JP 2015-124510 A (Patent No. 5807984 A)

The object of the present invention is therefore to improve upon the deficiencies of the prior art described above, and to provide a universal pipe joint for fluid passages that allows workers at the construction site to easily and precisely adjust and set the bending angle between pipes when connecting the pipes, in order to meet the delicate required setting angles required at the various connection points of the pipes that serve as the passageways for various fluid flows, mainly consisting of liquids, and as a result, allows pipe installation work to be easily carried out even in a narrow space, making it possible to significantly reduce the construction costs related to pipe installation work, while at the same time providing a universal pipe joint with high joint strength in its structure, allowing it to move, slide and rotate freely, and therefore having excellent earthquake resistance that allows it to absorb vibrations caused by earthquakes, etc.

In order to achieve the above object, the present invention employs the basic technical configuration described below.
That is, as a specific embodiment of the basic technical idea of the present invention, there is provided a universal joint used in a pipe joint, the universal joint being composed of a first connection structure portion composed of a first straight pipe portion and a first fitting portion composed of a first curved body connected to one end of the first straight pipe portion and forming a part of a first spherical body having a predetermined spherical curvature and a smooth outer surface, and a second connection structure portion composed of a second straight pipe portion and a second curved body connected to one end of the second straight pipe portion and forming a part of a second spherical body having substantially the same spherical curvature as the first curved body, the second fitting portion having substantially the same diameter as the diameter of the outer surface of the first curved body and having a smooth inner surface, the first and second fitting portions both having a spherical diameter larger than the diameters of the first and second straight pipe portions, and fitting together such that the first fitting portion is housed inside the second fitting portion. The first and second fitting portions are fitted and arranged so that their spherical centers coincide with each other, and the two are configured to be able to slide and rotate relative to each other in a watertight manner, and the central axes of the first and second straight pipe portions are arranged eccentrically so as not to pass through the spherical centers of the first and second fitting portions, and in a side cross-sectional view taken along a first plane formed by the spherical center and the central axis of the first or second straight pipe portion, the inside of the first or second straight pipe portion is A part of the surface and at least a part of the inner surface of the first or second fitting portion form a continuous flat portion, and the end peripheral portion of the first fitting portion is perpendicular to the first plane, which is a straight line connecting the first spherical center portion and the center line of the first straight pipe portion and which is set at an angle of 38 degrees to 68 degrees with the center line portion, in a side cross-sectional view seen on a first plane formed by the first spherical center portion and the central axis of the first straight pipe portion. The second fitting portion is formed at a position away from a reference plane inside the first sphere formed on the second plane in a direction opposite to the side where the first straight pipe portion is connected, by a length of 15 to 30% of the maximum diameter length of the sphere portion formed on the reference plane, while the end peripheral portion of the second fitting portion is formed on a fourth plane perpendicular to the third plane in a side cross section seen on a third plane formed by the second sphere center portion and the central axis of the second straight pipe portion, the fourth plane including a straight line connecting the sphere center portion and the center line portion of the second straight pipe portion and set at an angle of 38 degrees to 68 degrees with the center line portion, and further, the outer peripheral surface of the peripheral portion of the second connecting structure portion has at least one spiral protrusion portion or a spiral groove portion having a predetermined length, the outer peripheral surface of the peripheral portion is adjacently arranged at predetermined intervals along the outer peripheral surface and surrounding the peripheral portion. a fitting protrusion configured as a fitting protrusion is formed, while an annular reinforcing support is provided at a portion of the first and second connecting structures where the first and second fitting portions are fitted together, the reinforcing support being formed so as to cover the mutually fitting portion, the reinforcing support being composed of an upright annular cylindrical portion having a predetermined height and formed with a predetermined thickness and an outer diameter larger than an outer diameter of the fitting protrusion provided on the periphery of the second connecting structure, and a truncated hollow cone-like portion connected to an upper portion of the upright annular cylindrical portion and formed integrally therewith, the inner circumferential surface of the upright annular cylindrical portion being provided with a first annular recess formed with a predetermined height from a lower end surface of the upright cylindrical portion toward the top, the first annular recess being formed so as to be able to fit and engage with at least a portion of the outer circumferential edge portion and/or the fitting protrusion of the second connecting structure ,
Furthermore, a groove or protrusion is disposed on the inner wall of the first annular recess, which can slidably fit with the helical protrusion or helical groove formed on the outer surface of the fitting protrusion, while the outer peripheral surface of the truncated hollow cone-shaped portion is configured with an inclined surface having a predetermined angle with respect to the vertical central axis of the reinforcing support, and the inner peripheral surface of the truncated hollow cone-shaped portion has a spherical curvature substantially the same as the spherical curvature of the outer surface of the first fitting portion of the first connecting structure, so that the inner peripheral surface of the truncated hollow cone-shaped portion and the spherical outer surface of the first fitting portion can slide and rotate relative to each other in a watertight manner , and the overall height of the reinforcing support is greater than the spherical curvature of the second spherical outer surface of the second fitting portion of the second connecting structure. a first insertion hole portion having a predetermined length extending upward from the lower end surface of the fitting protrusion at a portion corresponding to a position where the continuity of the arrangement of the plurality of helical protrusions or helical grooves formed on the outer circumferential surface of the fitting protrusion is interrupted, and a second insertion hole portion having a predetermined length extending upward from the lower end surface of the reinforcing support at a portion corresponding to a position where the continuity of the arrangement of the plurality of helical protrusions or helical grooves formed on the outer circumferential surface of the fitting protrusion is interrupted, and a locking device integrally formed so that a first insertion pin portion and a second insertion pin portion formed to be insertable into the second insertion hole portion are parallel to each other, is inserted into the first and second insertion holes simultaneously to prevent relative movement between the second connection structure portion and the reinforcing support body, and further, in the first connection structure portion, an outer surface of the spherically curved surface portion of the first fitting portion is provided with a first outer surface portion adjacent to a joint boundary portion of the spherically curved surface portion of the first fitting portion corresponding to a portion where the length between an edge portion of the first straight pipe portion and the joint boundary portion is shortest, as measured in a direction parallel to the central axis of the first straight pipe portion, and a second outer surface portion adjacent to the joint boundary portion of the spherically curved surface portion of the first fitting portion corresponding to a portion where the length between the edge portion of the first straight pipe portion and the joint boundary portion is longest, a stopper portion consisting of a continuous annular protrusion arranged so as to pass through both the first outer surface portion and a second outer surface portion in contact with the first straight pipe portion, and a stopper portion notch formed in the first outer surface portion, the stopper portion notch having a length of 20 mm or less in each direction along the longitudinal axis of the stopper portion, centered on a portion of the stopper portion facing the first outer surface portion, in accordance with changes in the thickness or outer diameter of the first straight pipe portion, and further configured so that in the second outer surface portion, the portion of the stopper portion facing the second outer surface portion is set at a position between the same basic arrangement position as the second outer surface portion and an arrangement position a predetermined distance away from the basic arrangement position, in accordance with changes in the thickness or outer diameter of the first straight pipe portion.

According to the universal joint for pipe joints of the present invention, as a result of adopting the basic technical configuration as described above, the connection adjustment work between the multiple pipe sections to be connected, i.e., the straight pipe sections, is extremely easy, despite its simple configuration, and since there are no uneven obstacles at all on the inner surface of the connection part between the straight pipe sections, especially on the inner surface of the lower end, it has the function of not impeding the flow of gas or fluid, and further, in the universal pipe joint for fluid passages of the present invention, an extremely wide range of angle changes is possible in the adjustment operation of the set angle required between both straight pipe sections at the connection part of at least two consecutive straight pipe sections, and Fine angle setting and angle adjustment operations can be easily performed at each part, and the diameter of each connected straight pipe section can also be freely changed and adjusted, so the required piping gradient setting operations can be easily and quickly performed within the limited, narrow space of the piping passage, which has the effect of significantly reducing the cost of piping installation work. At the same time, it is no longer necessary to clean the inside of the piping using a high-pressure cleaning system, which is required to be performed at least once a year, especially for fluid piping, so the cost required for long-term maintenance and inspection work can also be significantly reduced.

Furthermore, in the universal pipe joint for fluid passages of the present invention, by combining the essential constituent elements described above, the straight pipe section is capable of rotating and changing direction in almost all directions, and at the same time, the area of the overlapping region between the spherical portions of the first and second fitting sections is designed to be large. Therefore, it exhibits high strength against vibration and external impacts and also has the function of absorbing vibration and impacts, and therefore shows great durability against impacts such as earthquakes and explosions. Therefore, it is possible to obtain a universal pipe joint for fluid passages with high earthquake resistance, which can significantly contribute to long-term maintenance effects.
Furthermore, by using at least two of the universal pipe joints for fluid passages according to the present invention in one line, the straight pipe sections of the universal joints can be freely oscillated, thereby providing the effect of providing greater earthquake resistance.

In addition, in conventional universal pipe joints for fluid passages, the pair of spherical portions each have a peripheral end portion located beyond the center of each spherical portion when viewed from the straight pipe portion of the respective spherical portion, so that the two connecting components that are mutually engaged can stably move, slide, and rotate relative to one another. However, when manufacturing a spherical portion with this structure, a large amount of money is required for the structure of the mold portion and for removing the mold after molding, and the mold removal operation is also complex and time-consuming, making it difficult to manufacture an inexpensive spherical portion easily and cheaply, and it is uneconomical.
Furthermore, in the conventional universal pipe joint for fluid passages according to the present invention, the operation of fitting the pair of spherical portions to each other is not an easy task, and the overall strength is maintained only at the mutually fitted parts of the pair of spherical portions. However, such a configuration has limitations in tensile strength and compressive strength, and has the disadvantage of being weak in durability against shaking movements caused by earthquakes, etc. However, in the present invention, the formation position of the peripheral edge portion of one of the pair of spherical portions is designed to be formed within a plane including the center line of that spherical portion. As a result, the manufacturing cost of the other spherical portion is significantly reduced, and at the same time, the operation of fitting the pair of spherical portions to each other is extremely simple and easy, thereby achieving the effect of significantly reducing manufacturing costs.

On the other hand, because the structure of the spherical body is partially deformed, the strength of the universal pipe joint for fluid passages is reduced, and at the same time, there is a risk of the boundary portion of the pair of spherical body parts forming a crack when the boundary portion is rotated or turned. Therefore, the above-mentioned annular reinforcing support body is configured to abut against the boundary portion of the pair of spherical body parts to improve strength and avoid the risk of cracks forming, thereby obtaining the effect of obtaining a universal pipe joint for fluid passages that is stronger, has excellent earthquake resistance, and is easy to operate.

FIG. 1 is a side view showing the configuration of one embodiment of a universal joint 100 for fluid passage according to the present invention. FIG. 2 is a vertical sectional view and a top perspective view showing the configuration of one example of a first connection structure including a first fitting portion constituting the universal joint 100 for fluid passages according to the present invention. FIG. 3 is a vertical sectional view and a bottom perspective view showing the configuration of one example of a second connection structure including a second fitting portion constituting the universal joint 100 for fluid passages according to the present invention. FIG. 4 is a vertical sectional view showing an example of the construction of the universal joint for fluid passages of the present invention shown in FIG. FIG. 5 is a plan view and a sectional view showing an embodiment of the auxiliary support used in the universal joint for fluid passages according to the present invention. FIG. 6 is a partially enlarged cross-sectional view of the auxiliary support in the present invention. FIG. 7A is a perspective view of the auxiliary support of the present invention, and FIG. 7B is a side view of the second connection structure including the second fitting portion of the present invention. FIG. 8 is a diagram showing the structure of one embodiment of a locking device used in the present invention. FIG. 9 is a partial cross-sectional view showing an embodiment of the packing portion used in the present invention.

The configuration of one embodiment of the universal pipe joint for fluid passage according to the present invention will be described in detail below with reference to the drawings. That is, Fig. 1 to Fig. 4 are diagrams showing an embodiment of the basic structure of the universal pipe joint for fluid passage 100 according to the present invention. In the drawings, the universal joint 100 is used for a pipe joint, and the universal joint 100 comprises a first connecting structure portion 8 composed of a first straight pipe portion 5 and a first fitting portion 7 composed of a first curved body 6 connected to one end of the first straight pipe portion 5 and forming a part of a first spherical body having a predetermined spherical curvature and a smooth outer surface; a second straight pipe portion 1 and The second curved body 2 is connected to one end of the second straight pipe section 1 and forms a part of a second spherical body having substantially the same spherical curvature as the spherical curvature of the first curved body 6, and the second fitting section 3 has a diameter substantially the same as the diameter of the outer surface of the first curved body 6 and a smooth inner surface. The first and second fitting sections 7, 3 each have a spherical diameter larger than the diameters of the first and second straight pipe sections 5, 1. The first and second fitting portions 7 and 3 are fitted together so that the first fitting portion 7 is housed inside the second fitting portion 3 , and are capable of sliding and rotating, and the first and second fitting portions 7 and 3 are fitted together so that their spherical centers P coincide with each other to the extent that the first and second fitting portions 7 and 3 can slide and rotate watertightly relative to each other, and the central axes Z1 and Z2 of the first and second straight pipe portions 5 and 1 are eccentrically arranged so as not to pass through the spherical centers P of the first and second fitting portions 7 and 3. In a side cross-sectional view taken along a first plane formed by the spherical center P and the central axis Z1, Z2 of the first or second straight pipe portion 5, 1, a part of the inner surface of the first or second straight pipe portion 5, 1 and at least a part of the inner surface of the first or second fitting portion 7, 3 form a continuous flat portion, and an end peripheral portion 13 of the first fitting portion 7 forms a continuous flat portion when viewed along a first plane formed by the first spherical center P and the central axis Z1 of the first straight pipe portion 5. In the side cross-sectional view, a straight line connecting the first spherical center P and the center line portion Z1 of the first straight pipe portion 5 and set at an angle F with the center line portion P within a range of 30 degrees to 62 degrees is formed on a second plane perpendicular to the first plane, and the straight pipe portion 5 is connected to a reference plane R inside the first sphere, the reference plane R being formed on the second plane perpendicular to the first plane, and including a straight line set at an angle F within a range of 30 degrees to 62 degrees, the reference plane R being formed on the second plane perpendicular to the first plane, and the straight pipe portion 5 is connected to the reference plane R by a length of 15 to 30% of the maximum diameter portion length of the spherical portion 6 formed on the reference plane R in a direction V opposite to the side to which the first straight pipe portion 5 is connected. The second fitting portion 3 is formed at a position spaced a length L from the plane R, while the end peripheral portion 12 of the second fitting portion 3 is formed on a fourth plane perpendicular to the third plane in a side cross-sectional view seen on a third plane formed by the second spherical center portion P and the central axis Z2 of the second straight pipe portion 1, the fourth plane including a straight line connecting the spherical center portion P and the center line portion Z2 of the second straight pipe portion 1 and set at an angle F' with the center line portion P in the range of 30 degrees to 62 degrees, and further The outer peripheral surface of the peripheral portion 12 of the first and second connection structures 4 is provided with a fitting protrusion 39 having at least one helical protrusion or a helical groove 37 having a predetermined length, the fitting protrusion 39 being arranged adjacent to each other at a predetermined interval U along the outer peripheral wall surface 38 of the peripheral portion 12 and surrounding the peripheral portion 12. Meanwhile, at the portion where the first and second fitting portions 7, 3 of the first and second connection structures 8, 4 are fitted to each other, The second connecting structure 4 has an annular reinforcing support 41 formed so as to cover at least a part of the interfitting portion 40, and the reinforcing support 41 is composed of an upright annular cylindrical portion 42 having a predetermined height H1 and formed with a predetermined thickness having an outer diameter larger than the outer diameter of the fitting protrusion 39 provided on the peripheral portion 12 of the second connecting structure 4, and a truncated hollow cone-shaped portion 43 connected to an upper portion of the upright annular cylindrical portion 42 and formed integrally therewith. The upright annular cylinder portion 42 has an inner peripheral surface 44 provided with a first annular recess 46 formed with a predetermined height H3 from a lower end surface 45 of the upright cylindrical portion 42 upward, the first annular recess 46 being formed so as to be able to engage with at least a part of the outer peripheral edge portion 12 and/or the fitting protrusion 39 of the second connecting structure portion 4. Furthermore, the first annular recess 46 has an inner wall portion 47 formed with the fitting protrusion 39. The truncated hollow cone-shaped portion 43 has an outer peripheral surface 50 formed with an inclined surface having a predetermined angle Θ with respect to the vertical central axis of the reinforcing support 41, and an inner peripheral surface 51 of the ... inner peripheral surface 51 formed with an inclined surface having a predetermined angle Θ with respect to the outer surface of the first fitting portion 7 of the first connecting structure portion 8. The reinforcing support 41 has a spherical curvature substantially the same as that of the spherical curvature of the truncated hollow cone-shaped portion 43, so that the inner peripheral surface of the truncated hollow cone-shaped portion 43 and the spherical outer surface of the first fitting portion 7 are configured to be watertight and capable of sliding and rotating relative to each other, and the overall height H2 of the reinforcing support 41 is 15 to 25 times larger than the maximum inner diameter of the peripheral portion 12 formed on the fourth plane passing through the center point P of the second spherical portion 2 in the second fitting portion 3 in the second connection structure portion 4. %, and a first insertion hole 54 having a predetermined length extending upward from the lower end surface 53 of the fitting protrusion 39 is provided at a portion corresponding to a position T where the continuity of the arrangement is interrupted in a situation where the plurality of spiral protrusions or spiral grooves 37 formed on the outer peripheral surface of the fitting protrusion 39 are continuously arranged in the longitudinal direction at a predetermined interval U, and a second insertion hole 52 having a predetermined length extending upward from the lower end surface 45 of the reinforcing support 41 is provided at a portion corresponding to a position T where the continuity of the arrangement is interrupted in the plurality of spiral protrusions or spiral grooves 37 formed on the outer peripheral surface of the fitting protrusion 39, and a predetermined base portion 55 and a first insertion pin portion 57 formed on the base portion 55 so as to be able to be fitted and inserted into the first insertion hole 54 and the second insertion hole portion The locking device 58 is integrally formed so that the second plug pin portion 56 formed to be able to be fitted and inserted into the first fitting portion 52 is in a mutually parallel state, and the locking device 58 having a locking device drop prevention function portion 59 is inserted individually and simultaneously into the first and second insertion hole portions 54, 52, respectively, to prevent the second connecting structure portion 4 and the reinforcing support body 41 from moving relative to each other. Furthermore, in the first connecting structure portion 8, the spherical bay of the first fitting portion 7 is The outer surface of the curved portion is provided with a first outer surface region 62 adjacent to the joint boundary 58 of the spherically curved surface portion of the first fitting portion, which corresponds to a region 61 where the length between the edge of the first straight pipe portion 5 and the joint boundary 58 is the shortest, as measured in a direction parallel to the central axis of the first straight pipe portion 5, at the joint boundary 58 between the first straight pipe portion 5 and the first fitting portion 7; and a second outer surface region 63 adjacent to the joint boundary 58 of the spherically curved surface portion of the first fitting portion, which corresponds to a region 64 where the length between the edge of the first straight pipe portion 5 and the joint boundary 58 is the longest, as measured in a direction parallel to the central axis of the first straight pipe portion 5. and a second outer surface region 64 adjacent to the joint boundary portion 58 of the spherically curved surface portion of the first fitting portion 7, and a stopper portion notch is formed in the first outer surface region, the stopper portion notch having a length of 0 mm to 20 mm (20 mm or less) in each direction along the longitudinal axis of the stopper portion, centered on the portion of the stopper portion facing the first outer surface region, in accordance with changes in the wall thickness or outer diameter of the first straight pipe portion, and the second outer surface region is configured so that the portion of the stopper portion facing the second outer surface region is set to any position between the same basic position as the second outer surface region and an position spaced a predetermined distance from the basic position, in accordance with changes in the wall thickness or outer diameter of the first straight pipe portion.

The universal pipe joint 100 for fluid passages according to the present invention is based on the basic technical concept of the universal pipe joint for fluid passages that the inventor himself has disclosed in the already published Patent Publication No. 5807984 or Patent Publication No. 6083032984, and is a further improvement and development of that technical concept.

That is, the universal pipe joint 100 for fluid passage according to the present invention employs the above-mentioned basic technical configuration, so that the area of the mutually overlapping portion of the first and second curved fitting portions 7 and 3 is minimized, and the fitting and joining portion of the first and second curved fitting portions 7 and 3 slides and rotates more firmly, stably, and easily relative to each other, and the inclination angle F of the reference plane T of the first curved fitting portion 7 with respect to the central axis Z1 of the straight pipe 5 is limited within the above-mentioned specific range. As a result, the swing angle range M of the straight pipe section 1 provided on the second fitting section 3 relative to one fitting section 7 when viewed on the first plane S1 can be set larger than that of conventional universal joints, and the straight pipe section 5 provided on the first fitting section 7 can rotate 360 degrees around the axis P2 that passes through the fitting center point P and is parallel to the axis Z1 of the straight pipe section 5, as shown by the arrow N. As a result, the piping connection angle can be set in almost any direction.

On the other hand, in the second fitting portion 3, the peripheral portion 12 of the second curved spherical portion 2 is set and arranged at a position indicating the maximum diameter portion of the curved spherical portion 2 including the center P of the second curved spherical portion 2. This achieves a reduction in the cost of molding the spherical portion and a significant improvement in production efficiency, and reduces the overlapping area of the two spherical portions 6, 2 that are fitted together as described above, allowing for smooth turning and sliding operations. Furthermore, even if at least a portion of the peripheral portions of the two spherical portions 6, 2 is opened, the reinforcing support body 41 can fully cover this defect. Furthermore, the reinforcing support body 41 provides an overall reinforcing function for the universal pipe joint for fluid passages 100 and ensures easier and more stable turning and sliding operations. In addition, it can also exhibit an absorbing effect against vibrations and shaking caused by earthquakes, etc., and can exhibit excellent earthquake resistance.

In this invention, "almost all directions" does not mean all directions in the complete sense, but rather means that it is extremely flexible and any bending angle can be easily selected and set within the range of rotation and bending angles required for the piping connection work.
The universal joint 100 for fluid passage according to the present invention may be used for any gas, but is particularly effective in the field of processing fluids including liquids.
Furthermore, the material constituting the universal pipe joint 100 for fluid passages in the present invention is not particularly specified, but for example, metals and various commonly used synthetic resins such as polyvinyl chloride resin and polyethylene resin are preferably used, and it is also desirable for the material to be composed of FRP resin containing reinforcing materials including glass fiber or carbon fiber, ceramics, etc.

Furthermore, in the present invention, the diameter (inner diameter) X1 of the straight pipe section 5 provided in the first connection structure section 8 and the diameter (inner diameter) X2 of the straight pipe section 1 provided in the second connection structure section 4 may be the same as or different from each other, and in the present invention, it is possible to use any combination of straight pipe sections having different diameters.
However, when the second fitting portion 3 is used downstream with respect to the direction of flow of the fluid used, and the first fitting portion 7 is used upstream with respect to the direction of flow of the fluid used, it is desirable that the bore (inner diameter) X2 of the straight pipe portion 1 of the second fitting portion 3 be larger than the bore (inner diameter) X1 of the straight pipe portion 5 of the first fitting portion 7.

Next, the configurations of the first connecting structure 8 and the second connecting structure 4 used in the universal pipe joint 100 for fluid passages according to the present invention will be described more specifically.
The technical configuration of each connection structure part of the present invention is basically based on the technical ideas and experimental result data disclosed in Patent Gazette No. 5,807,984, to which new improved technologies have been added.
First, a specific configuration of the first connection structure 8 in the present invention will be described.
In order to solve the various problems associated with the conventional pipe joints described above, the present inventor considered the results of numerous experiments described in the above-mentioned Patent Publication No. 5,807,984 and pursued the necessary configurational elements of a universal joint required to achieve the object of the present invention. As a result, it was found that an approximately ideal universal joint can be obtained by limiting, within a desired value range, one or more of the following: the angle F between the reference plane T inside the curved sphere 6 in the first connection component 8 and the center line Z1 of the straight pipe section 5, the distance L by which the end peripheral portion 13 is separated from the reference plane T, or the ratio of the length R2 of the maximum diameter inside the sphere 6 to the diameter X1 of the straight pipe section 5.

That is, FIG. 2A is a side view illustrating the configuration of the first connecting structure 8 according to the present invention, and FIG. 2B is a top perspective view thereof.
In other words, in the first connection structure 8 of the present invention, in a side cross-sectional view of the reference plane T as viewed on the first plane S1 formed by the spherical center P and the central axis Z1 of the first straight pipe section 5, a straight line W0 connecting the spherical center P and the center line Z1 of the straight pipe section 5 is set at a predetermined angle F with the center line Z1, and the line 58 in Figure 2 (B) is a connecting line indicating the location where the first straight pipe section 5 and the first curved spherical section 6 are joined to each other.

The basic structure of the first connection structure 8 is as described above, and in particular, it is desirable to set the maximum diameter R2 of the spherical curved portion in the first fitting portion 7 to be 1.2 to 2.0 times larger than the diameter X1 of the first straight pipe portion 5, and it is particularly preferable to set the maximum diameter R2 of the spherical curved portion 6 to be 1.6 times larger than the diameter X1 of the first straight pipe portion 5.
That is, when the ratio R2/X1 is 1.2 or less, there is no substantial difference between the maximum diameter R1 of the spherical curved portion and the diameter X1 of the first straight pipe portion, and as a result, the rotation angle of the first straight pipe portion 5 is significantly restricted, and it is impossible to rotate it from the free angle of 90 degrees. In other words, the angle range is narrowed, and at the same time, the area of the overlapping region between the first fitting portion 3 and the second fitting portion 6 is narrowed. Therefore, it is impossible to arrange a gasket 15 as described later, and the strength of the contact surface between the two types of spherical bodies is reduced, and the stability during rotation is reduced, which has the disadvantage that the strength of the universal joint itself or its stability during use is greatly impaired.

On the other hand, when the ratio R1/X1 is 2.0 or more, the substantial difference between the maximum diameter R1 of the spherical curved portion and the diameter X1 of the first straight pipe portion becomes large, and the spherical portion becomes large. As a result, the rotation angle of the first straight pipe portion 5 becomes large. However, on the other hand, the joint area of the attachment portion between the spherical portion 6 of the first fitting portion 7 and the first straight pipe portion 5 becomes small, resulting in a decrease in strength, and a problem occurs in that the strength and durability of the entire universal joint is reduced.
Furthermore, under these conditions, if it is desired to increase the diameter X1 of the first straight pipe section 5, the diameter of the spherical section 6 of the first fitting section 7 becomes extremely large, and the size of the universal joint itself also becomes large. This not only increases the manufacturing cost, but also increases the area of use, i.e., the spatial area in which piping can be installed, so that the universal joint cannot be used unless it is large, resulting in a problem that the freedom of construction conditions is significantly restricted.

As described above, the present invention was carried out by thoroughly examining samples in which various combination conditions were individually changed, and as a result, it was found that the sample in which the ratio R1/X1 was 1.6 exhibited the most preferable characteristics, and therefore it was determined that the optimal value for the ratio R1/X1 was 1.6.
Therefore, in the present invention, the ratio R1/X1 is preferably 1.2 to 2.0, and more preferably 1.6.
In the present invention, it is an extremely important technical component that the end peripheral portion 13 of the first fitting portion 7 is set at a specific portion of the first fitting portion 7 described above, and as the basic technical idea is described in detail in the patent, the end peripheral portion 13 of the first fitting portion 7 is set at a specific portion of the first fitting portion 7 as shown in FIG. 2 and FIG. 4, in a side cross-sectional view taken on a first plane S formed by the center P of the first spherical portion 6 and the central axis Z1 of the first straight pipe portion 5, The first sphere 6 is formed on a second plane perpendicular to the first plane S, and includes a group of straight lines (W0, W1, W2, etc.) connecting the center line portion Z1 of the straight pipe portion 5 and the first sphere 6, the group of straight lines (W0, W1, W2, etc.) including a straight line set at an angle F within a range of 38 degrees to 68 degrees with the center line portion P. The first sphere 6 is formed in a position away from the reference plane R by a length L that is 15 to 30% of the maximum diameter length of the spherical portion 6 formed on the reference plane R, in a direction V opposite to the side to which the first straight pipe portion 5 is connected, relative to a reference plane R inside the first sphere 6 formed on the second plane perpendicular to the first plane S.

Furthermore, according to the setting conditions of the present invention, for example, when the linear distance (length) L from the reference plane T to the end periphery 13 is set to 20% of the maximum diameter R2 of the spherical portion 6, and the inclination angle F of the reference plane T with respect to the central axis Z1 of the straight pipe portion 5 is set to 45 degrees, the angle Q1 detailed in the patent is 89 degrees to 111 degrees, the angle Q2 is 159 degrees to 187 degrees, the allowable range of each angle is 28 degrees, and the angle Q3 is 106 degrees, and it has been recognized that the device has a rotation function in almost all directions.

Next, the specific configuration of the second connection structure 4 used in the present invention is as shown in the side view and top perspective view of Figure 3 (A) and Figure 3 (B), and its basic configuration, referring to Figure 3 and Figure 4, the end peripheral portion 12 of the second spherical curved body portion 2, which is the main portion of the second fitting portion 3 constituting the second connection structure portion 4, is configured to be formed on a fourth plane perpendicular to the third plane, including a straight line (Y0, Y1, Y2, ...) connecting the spherical center P and the center line portion Z2 of the second straight pipe portion 1, and a straight line set at an angle F' within the range of 30 degrees to 62 degrees with the center line portion P, in a side cross-sectional view seen from a third plane S formed by the second spherical center P and the central axis Z2 of the second straight pipe portion 1.

In other words, the end peripheral portion 12 of the second spherically curved body portion 2, which is the main portion of the second fitting portion 3 that constitutes the second connection structure portion 4, is characterized in that it is formed and arranged on a plane that includes the center point P of the second spherically curved body portion 2.
In the present invention, the reason for limiting the angle F formed by the straight line (W0, W1, W2, etc.) connecting the spherical center P and the center line portion Z1 of the first straight pipe section 5, and the angle F' formed by the straight line (Y0, Y1, Y2, etc.) connecting the spherical center P and the center line portion Z2 of the second straight pipe section 1 to within the range of 38 degrees to 68 degrees is made clear by the detailed experimental data backing up in the patent.

In addition, in the present invention, the restrictive condition that the position of the end peripheral portion 13 of the first fitting portion 7 is formed in a position away from the reference plane R by a length L that is 15 to 30% of the maximum diameter portion length of the spherical portion 6 formed on the reference plane R, in a direction V opposite to the side to which the first straight pipe portion 5 is connected, relative to a reference plane R inside the first sphere 6 formed on a second plane perpendicular to the first plane S, is also made clear with the support of detailed experimental data in the patent.
Furthermore, in the present invention, the outer surface of the first spherical body 6 which forms the first mating portion 7 constituting the first connecting body 8 in the universal pipe joint 100 for a fluid passage, and the inner surface of the second spherical body 2 which forms the second mating portion 3 constituting the second connecting body 4 are both composed of flat surfaces, without any protrusions, recesses or uneven portions, and therefore the abutment portion at the mutual fitting portion of the first spherical body 6 and the second spherical body 2 is maintained in a state in which they can slide easily, freely and lightly without any obstacles.

On the other hand, in the present invention, the first and second mating portions 7, 4 are formed into the shapes described above, which contributes greatly to cost reduction. However, in the region 40 where the first and second mating portions 7, 3 of the first and second connecting structures 8, 4 are mated with each other, the mating portions are easily destroyed. Therefore, in order to maintain the mutual sliding and rotating functions of the two mating portions and to prevent them from separating from each other, a reinforcing support member 41 such as that shown in Figures 5 and 6 is used as described above.
That is, the basic aspect of the reinforcing support is that an annular reinforcing support 41 is provided so as to cover at least a portion of the mutually interfitting portion 40, and the reinforcing support 41 is composed of an upright annular cylindrical portion 42 having a predetermined height and formed with a predetermined thickness having an outer diameter larger than the outer diameter of the interfitting protrusion 39 provided on the peripheral portion 12 of the second connection structure portion 4, and a truncated hollow cone-shaped portion 43 connected to the upper portion of the upright annular cylindrical portion 42 and formed integrally therewith, and is composed of the same material as the first and second connection structures 8, 4.

The configuration for fitting the reinforcing support 41 to the first and second connection structures 8, 4 is, for example, as shown in FIG. 3, first, on the outer peripheral surface of the peripheral portion 12 of the second fitting portion 3 in the second connection structure 4, one helical protrusion or spiral groove portion 37 having at least a predetermined length is provided, and multiple fitting protrusions 39 are arranged adjacent to each other at a predetermined interval U along the outer peripheral wall surface 38 of the peripheral portion 12 and surrounding the peripheral portion 12, while the reinforcing support 41 is formed with a predetermined thickness having an outer diameter larger than the outer diameter of the fitting protrusion 39 provided on the peripheral portion 12 of the second connection structure 4. It is composed of an upright annular cylindrical portion 42 having a predetermined height and a truncated hollow cone-shaped portion 43 connected to the upper portion of the upright annular cylindrical portion 42 and formed integrally therewith. The inner peripheral surface portion 44 of the upright annular cylindrical portion 42 is provided with a first annular recess 46 for receiving at least a part of the fitting protrusion 39 formed with a predetermined height upward from the lower end surface 45 of the upright cylindrical portion 42. Furthermore, the inner wall portion 47 of the first annular recess 46 is provided with a groove or protrusion 48 that can slidably fit with the spiral protrusion or groove 37 formed on the outer surface 38 of the fitting protrusion 39.

On the other hand, the outer peripheral surface 50 of the truncated hollow cone-shaped portion 43 is formed of an inclined surface having a predetermined angle with respect to the vertical central axis of the reinforcing support 41, and the inner peripheral surface 51 of the truncated hollow cone-shaped portion 43 has a spherical curvature that is substantially the same as the spherical curvature of the outer surface of the first fitting portion 7 in the first connection structure portion 8, thereby exerting the function of abutting the first fitting portion 7 against the second fitting portion 3 with an appropriate pressure while making strong planar contact with the inner peripheral surface of the truncated hollow cone-shaped portion 43, and is configured so that the spherical outer surface of the first fitting portion 7 can easily slide and rotate against each other in any direction in a watertight manner.

Furthermore, it is a desirable example that the overall height H2 of the reinforcing support 41 is set to a height equivalent to a length of 15 to 25% of the maximum inner diameter of the peripheral portion 12 formed on the fourth plane passing through the center point P of the second spherical body portion 2 in the second fitting portion 3 in the second connection structure portion 4.
The dimensions of each portion of the reinforcing support in the present invention are not particularly limited. For example, in the case of the specific example of the second fitting portion 3 shown in FIG. 3, referring to FIG. 5, the maximum inner diameter R of the second fitting portion 3 is 142.6 mm, so that the maximum diameter of the lower end of the reinforcing support 41 is 172 mm, the height H1 of the upright annular cylinder 42 is 20 mm, the height H3 of the first recessed portion 46 of the upright annular cylinder 42 is 15 mm, the height H2 of the reinforcing support 41 is 35 mm, and the thickness, i.e., the wall thickness, is 3.0 mm to 3.5 mm. Also, the inclination angle Θ of the outer surface of the truncated hollow cone-shaped portion 43 with respect to the central axis of the truncated hollow cone-shaped portion 43 is 25 degrees.
In the present invention, by using the auxiliary support 41, the set position of the outer peripheral edge 12 of the second fitting portion 3 is set to be exactly the same as the set position of the outer peripheral edge 13 of the first fitting portion 7, as if it had been moved within the range of the above-mentioned conditions in the direction of the existence of the first fitting portion 7, even though the actual outer peripheral edge 12 of the second fitting portion 3 is formed on a plane including the center point P of the sphere in the second fitting portion 3. As a result, the fitting effect of both is improved, and the sliding and turning effect is achieved more smoothly and stably.

Here, as shown in FIG. 3 of the present invention, the helical protrusion or helical groove 37 provided on the outer peripheral surface of the peripheral portion 12 of the second fitting portion 3 in the second connection structure portion 4 will be described in more detail with reference to FIG. 3(C). FIG. 3(C) is a planar development of the entire outer peripheral surface of the peripheral portion 12 of the second fitting portion 3, and as is clear from the figure, a plurality of helical protrusions or helical grooves 37, each of which has at least a predetermined length and is arranged in a parallel combination, are arranged adjacent to each other at a predetermined interval U along the outer peripheral wall surface 38 of the peripheral portion 12 and surrounding the peripheral portion 12.

As a preferred example of the present invention, at least two sets of the spiral protrusion or spiral groove 37-1, 37-2, ... 37-n, which is composed of one or more pieces, must be provided, and each set must be arranged in a location that covers half the circumference so as to divide the length of the outer circumferential surface of the peripheral portion 12 in half, or they may be arranged in a divided arrangement, such as one-third or one-quarter of the length of the outer circumferential surface of the peripheral portion 12.

On the other hand, it goes without saying that the groove or protrusion 48 provided on the inner wall 47 of the first annular recess 46 formed on the inner surface 44 of the upright annular cylindrical portion 42 of the reinforcing support 41 is arranged so as to be able to slidably engage with the spiral shape of the spiral protrusion or groove 37 formed on the outer surface 38 of the fitting protrusion 39.
It goes without saying that in the present invention, when the object formed on the outer peripheral surface of the engaging protrusion 39 is a protrusion-like object, a corresponding groove portion is formed on the inner peripheral surface 44 of the upright annular cylindrical portion 42 of the reinforcing support 41, and when the object formed on the outer peripheral surface of the engaging protrusion 39 is a groove-like object, a corresponding protrusion-like portion is formed.

In the present invention, the first and second fittings 7, 3 can be held firmly and stably by screwing the multiple spiral projections or spiral grooves 37 formed on the outer peripheral surface of the fitting protrusion 39 in the second fitting 3 as described above into the groove or protrusion 48 of the reinforcing support 41. Moreover, the reinforcing process uses multiple split screws, making the screwing operation extremely easy, and the tightening effect is much more effective than conventional reinforcing means. In addition, the compressive strength and tensile strength between the first and second fittings 7 and 3 are significantly improved, and the rotation and sliding between the two are ensured more smoothly. At the same time, it is possible to maintain the absorbing effect against shaking caused by earthquakes, etc., so a pipe joint with excellent earthquake resistance, operability, and workability is realized.

Furthermore, in the present invention, in order to further improve the strength between the first and second mating portions 7 and 3, and to prevent the occurrence of misalignment and loosening between the reinforcing support 41 and the second mating portion 3, a locking device as described below is introduced.
That is, referring to Figures 6 and 7, in the present invention, first, as shown in Figure 6, in a situation where the multiple spiral protrusions or spiral grooves 37 are continuously arranged in the longitudinal direction at a predetermined interval U on the lower end surface 53 of the engagement protrusion portion 39, a first insertion hole portion 54 having a predetermined length extending upward from the lower end surface 53 of the reinforcing support body 39 is provided at a position corresponding to the position Q where the continuity of the arrangement is interrupted.

On the other hand, a second insertion hole portion 52 having a predetermined length extending upward from the lower end surface 45 of the reinforcing support body 41 is provided at a position on the lower end surface 45 of the reinforcing support body 41 corresponding to the position T where the continuity of the arrangement of the multiple spiral protrusions or spiral groove portions 37 formed on the outer peripheral surface of the fitting protrusion portion 39 is interrupted.
Furthermore, as shown in Figure 8, a locking device 58 is separately prepared, which is made of an appropriate synthetic resin material or metal material and has a first plug pin portion 56 formed to be able to be fitted and inserted into the first insertion hole portion 54 and a second plug pin portion 57 formed to be able to be fitted and inserted into the second insertion hole portion 52, which are integrally formed on a specified base portion 55 so that they are parallel to each other.The locking device 58 is then pushed upward from the lower end surface 45 of the reinforcing support body 41 and the lower end surface 53 of the engagement protrusion portion 39 so that the first and second plug pin portions 56 and 57 are individually and simultaneously inserted into the specified first insertion hole portion 54 and second insertion hole portion 52, respectively.
This prevents the second connection structure 4 and the reinforcing support 41 from moving relative to each other.
Furthermore, in the present invention, the first insertion hole portion 54 and the second insertion hole portion 52 indicate the target operation start positions when a worker at a desired construction site performs a screw-fitting operation between the auxiliary support body 41 and the engaging protrusion portion 39 by engaging the two and starting the screwing operation, which greatly contributes to improving work efficiency.

The dimensions of the locking device 58 used in the present invention are not particularly limited, but for example, as illustrated in FIG. 8, it is configured as a plate-like body with a length C of 14 mm, a width D of 6.8 mm, and a thickness E of 4 mm, and further, the basic width of the first plug pin portion 56 connected to the base portion 55 is 3 mm, and the basic width of the second plug pin portion 57 is 2 mm.
In addition, the outer surface of the first plug pin portion 56 is provided with a fall prevention function portion 59 of an appropriate shape that can engage and disengage with an appropriate protrusion (not shown) formed in the first insertion hole portion 54, while the side portion of the base portion 55 on which the second plug pin portion 57 is formed is provided with an operating groove portion 60 into which the tip portion of an operating instrument such as a suitable screwdriver can be inserted to separate and remove the locking device 58 from both insertion holes 52, 54, which is a preferred example.

On the other hand, in the above explanation, an example was shown in which the second and first insertion hole portions 52, 54 are individually arranged on the lower end surface portion of the auxiliary support 41 and the lower end surface portion of the mating protrusion portion 39, respectively, while being independent of and spaced apart from each other. However, in some cases, the two may be close to each other and formed integrally in a continuous state across the boundary surface between the auxiliary support 41 and the mating protrusion portion 39.
Furthermore, in the first connection structure 8, a stopper portion 30 consisting of a continuous protrusion having an annular shape is provided on the outer surface of the spherically curved surface portion of the first fitting portion 7, the stopper portion 30 being configured to pass through both a first outer surface portion 62 adjacent to the joint boundary portion 58 of the spherically curved surface portion of the first fitting portion 7 corresponding to a portion 61 at the joint boundary portion 58 between the edge portion of the first straight pipe portion 5 and the joint boundary portion 58 where the length is shortest, measured in a direction parallel to the central axis Z1 of the first straight pipe portion 5, and a second outer surface portion 64 adjacent to the joint boundary portion 58 of the spherically curved surface portion of the first fitting portion 7 corresponding to a portion 63 at the joint boundary portion 58 where the length is longest, the second outer surface portion 64 being adjacent to the joint boundary portion 58 of the spherically curved surface portion of the first fitting portion 7 corresponding to a portion 63 at the joint boundary portion 58 between the edge portion of the first straight pipe portion 5 and the joint boundary portion 58 where the length is longest.

The protruding shape of the stopper 30 is not particularly limited, and the height is preferably 1 mm to 5 mm. The presence of the stopper portion prevents the rotation angle of the first straight pipe section 5 from increasing excessively, while at the same time facilitating the rotation and swinging action during the operation stage of the pipe joint, and reliably protecting the pipe joint from unexpected destructive action.

The universal joint 100 according to the present invention basically utilizes the technical idea disclosed in the above-mentioned Patent No. 5,807,984, and the basic technical idea is, for example, to set the angle F between the central axis Z1 of the first straight pipe section 5 and the reference plane T at the first fitting section to 38 degrees to 68 degrees, preferably 65 degrees, in order to allow the straight pipe section 5 of the first connection structure 8 to slide and rotate over as wide a range as possible relative to the second connection structure 4, but the angle F is set to 38 degrees to 68 degrees, preferably 65 degrees, up to 45 degrees. , a relatively large space is created in the vicinity of the first outer surface portion 62 adjacent to the joint boundary portion 58 of the spherically curved surface portion of the first fitting portion 7 corresponding to the portion 61 with the shortest length between the edge portion of the first straight pipe portion 5 and the joint boundary portion 58, making it possible to individually place the stopper portion 30. However, if the angle F is changed beyond 45 degrees to about 65 degrees, there will be no room in the vicinity of the first outer surface portion 62, making it physically impossible to place the stopper portion 30.

For this reason, in the present invention, under the former setting conditions, it is possible to provide a stopper portion 30 consisting of a continuous protrusion presenting a complete ring shape that is arranged so as to pass through both the first outer surface region 62 and the second outer surface region 64, but under the latter setting conditions, it is preferable to provide a stopper portion cutout portion 31 consisting of a space of about several centimeters on the left and right sides of the first outer surface region 62 as shown in Figure 1, thereby forming a discontinuous annular stopper portion 30.
Here, to further explain the arrangement of the stopper portion 30 in the present invention, it is a preferred embodiment that the arrangement of the stopper portion 30 or the shape of the stopper portion 30 is configured to be changed depending on the outer diameter or the wall thickness of the first straight pipe 5 used.
That is, according to the results of numerous experiments conducted by the inventors of the present application, it has been determined that, when the assembly angle of the pipe fitting 100 is constant, it is preferable to configure the length of the stopper portion absence portion 31 provided in the vicinity of the first outer surface region 62 of the stopper portion 30 to increase as the outer diameter of the first straight pipe 5 increases or the thickness thereof decreases; on the other hand, when the assembly angle of the pipe fitting 100 is constant, it is preferable to configure the position of the stopper portion 30 provided in the vicinity of the second outer surface region 64 of the stopper portion 30 to change in a direction away from the second outer surface region 64 as the outer diameter of the first straight pipe 5 increases or the thickness thereof decreases.
More specifically, in the first outer surface region 61, a stopper portion notch 31 is formed with a length of 0 mm to 20 mm in both directions along the longitudinal axis direction of the stopper portion 30, centered on the portion of the stopper portion 30 facing the first outer surface region 62, in accordance with changes in the thickness or outer diameter of the first straight pipe portion 5. Also, in the second outer surface region 64, in accordance with changes in the thickness or outer diameter of the first straight pipe portion, the portion of the stopper portion 30 facing the second outer surface region 64 is configured to be set at any position between the same basic arrangement position as the second outer surface region 64 and an arrangement position a predetermined distance away from the basic arrangement position 64.
In addition, in the present invention, as shown in Figure 6, a preferred embodiment is to form a second annular recess 70 having a desired height and depth at the portion of the annular inner wall surface 44 of the reinforcing support portion 41 that abuts and joins with the upper surface portion of the outer peripheral edge portion 12 of the second fitting portion 3 in the second connecting structure portion 4, and to store a desired annular packing material 71 inside the second annular recess 70.

In this specific example, the height and depth of the second annular recess 70 are not particularly limited, and can be set to any appropriate dimensions.
Furthermore, the characteristics or shape of the packing material 71 used in the present invention are not particularly specified, but, for example, a packing material made of silicone resin and formed in a ring shape can be preferably used. In addition, as for the shape configuration, for example, as shown in FIG. 9, an inner wall surface portion 72 of the annular packing material 71 has at least one recessed annular groove portion 73 formed with a predetermined depth along the longitudinal direction of the annular packing material 71 from the surface of the inner wall surface portion 72 of the annular packing material 71 toward the direction of the outer wall surface portion 74 of the annular packing material.

As described above, the present invention adopts a technical concept that organically combines new and highly progressive technical configurations, and therefore a universal joint, particularly for connecting fluid piping, that can exhibit the remarkable effects described above can be obtained. In particular, it provides a universal joint that is economical because it allows piping installation and repair work, including packing replacement, to be carried out simply, easily and quickly on site.
Furthermore, there are no unevenness whatsoever on the inner or outer surfaces of both mating portions 7, 3, and the rotatable annular auxiliary support 41 is used to screw-fit and engage both mating portions 7, 3 together, which allows for easy and quick installation and repair work on site, and the axial alignment of the pipes can be accurately performed. Furthermore, the strength, flexibility, durability, and earthquake resistance between the two mating portions can be significantly improved, and both straight pipe portions 5, 1 can easily move, slide, and rotate freely in almost all directions. In addition, the structure has excellent shaking absorption properties, especially during earthquakes, resulting in significantly high earthquake resistance.

Furthermore, by adopting a locking device in the auxiliary support, it is possible to reliably resolve the serious problem of the tightening force of the auxiliary support decreasing during use, thereby achieving further improvement in durability.
Meanwhile, in the past, when performing various piping work using such a universal pipe joint, at least two workers were required to be positioned on both sides of the pipe joint and adjust the angles on both sides while actually checking the alignment of the pipes and the placement position and inclination angle of the piping pipes to be connected. In contrast, when the universal pipe joint of the present invention is used, all of the operations that were previously performed simultaneously and individually by the two workers can now be completed completely, quickly, easily and in a short time by a single worker, making it possible to significantly reduce the total cost including labor costs required for the work.

Furthermore, by making the external shape of the auxiliary support in the present invention an integrally combined structure of a cylindrical shape and a truncated hollow conical portion, firstly, the strength (tensile strength, compressive breaking strength, etc.) of the auxiliary support as a single component is increased, thereby strengthening the overall strength of the support itself and contributing to improved abrasion resistance. In addition, the overall external shape is compact and neat, adding to its aesthetic appeal, thereby reducing manufacturing costs and maintaining the structural beauty of the construction site in a form that is preferred by consumers and users, and also providing excellent workability.
Furthermore, due to the shape of the auxiliary support in the present invention, it is possible to reliably reinforce the strength of the peripheral edge of the second fitting portion, and it is also possible to use a screw-type fastening method to connect the two parts around the entire circumference, which makes it possible to significantly facilitate and speed up the operation of connecting the two parts.As a result, the connection operation at the construction site can be completed reliably by simply rotating the auxiliary support pipe, which greatly contributes to work efficiency.

On the other hand, the inner wall surface of the truncated hollow cone-shaped portion of the auxiliary support is set to the same curvature as the spherical outer surface curvature of the first fitting portion 7, so that the inner wall surface of the truncated hollow cone-shaped portion and the spherical outer surface of the first fitting portion 7 can be reliably pressed against each other with a predetermined contact pressure. This allows the first fitting portion 7 and the second fitting portion 3 to move, slide, and rotate in any direction they like, and at the same time, they do not move in a completely free state, but are able to move under a predetermined contact pressure. This completely prevents the two surfaces from moving or sliding on their own, and they can move, slide, and rotate only when an appropriate pressure force is applied. The universal pipe joint is designed to be able to perform such movements, so that it can only slide or move when a certain vibration, such as an earthquake, is applied, and can absorb the excessive vibration. In addition, when the universal pipe joint is attached to one end of the pipe during installation work and then the same operation is performed on the other end, the set angle of the universal pipe joint that was attached to the one end may shift unexpectedly, which may require repeated correction work. However, with the universal pipe joint of the present invention, such defects do not occur at all, and as described above, installation work can be easily and quickly performed by a single worker.

Furthermore, in the universal pipe joint 100 of the present invention, it is possible to provide a packing material 71 on the inner wall surface 51 of the truncated hollow cone-shaped portion 43 of the auxiliary support 41. The presence of such packing material 71 not only completely prevents leakage of the liquid flow being treated from the second fitting portion 3, but also completely prevents leakage from the first fitting portion 7, providing a double liquid leakage prevention effect.

1: second straight pipe section 2: second curved body 3: second fitting section 4: second connection structure section 5: first straight pipe section 6: first curved body 7: first fitting section 8: first connection structure section 9, 10: part of inner surface 11: continuous flat section 12: end peripheral edge section of second fitting section 13: end peripheral edge section of first fitting section 30: stopper section 31: stopper section notch 37: helical protrusion section or helical groove section 38: outer peripheral wall surface of peripheral section, outer surface of fitting protrusion section 39: fitting protrusion section 40: interfitting section 41: annular reinforcing support 42: upright annular cylindrical section 43: truncated hollow cone section 44: Inner peripheral surface portion of upright annular cylindrical body portion 45: Lower end surface of upright cylindrical body portion of reinforcing support 46: First annular recess portion 47: Inner wall portion of first annular recess portion 48: Groove portion or protrusion portion 50: Outer peripheral surface portion of truncated hollow cone-shaped portion 51: Inner peripheral surface portion of truncated hollow cone-shaped portion 52: Second insertion hole portion 53: Lower end surface of fitting protrusion portion 54: First insertion hole portion 55: Base portion 56: First bayonet portion 57: Second bayonet portion 58: Joint boundary portion between first straight pipe portion and first fitting portion 59: Fall-off prevention function portion for locking device 60: Operation groove portion 61: Region 62 where the distance between the edge of the first straight pipe portion and the joint boundary portion of the first straight pipe portion is the shortest: First outer surface region 63: Region 64 where the distance between the edge of the first straight pipe portion and the joint boundary portion of the first straight pipe portion is the longest: Second outer surface region 68: Locking device 70: Second annular portion recessed portion 71: Annular packing material 72: Inner wall surface portion 73 of the annular packing material: Concave annular groove portion 74: Outer wall surface portion 100 of the annular packing material: Universal pipe joint for fluid passage W0, W1, W2: Straight lines Y0, Y1, Y2 connecting the center of the first sphere and the center line portion Z1 of the first straight pipe portion: Second sphere Straight line F connecting the center and center line Z2 of the second straight pipe section: angle F' between the center of the curved sphere and center line Z1 of the first straight pipe section: angle L between the center of the curved sphere and center line Z2 of the second straight pipe section: distance T that the end peripheral section is away from the reference plane T: reference plane Z1 inside the first sphere: central axis Z2 of the first straight pipe section: central axis R of the second straight pipe section: reference plane L inside the first sphere: length U from reference plane R: mutual separation distance Q of the helical protrusions or helical grooves: portion where the continuity of the helical protrusions or helical grooves is interrupted

Claims (3)

A universal joint used in a pipe joint,
The universal joint is
a first connecting structure part including a first straight pipe part and a first fitting part including a first curved body that is connected to one end of the first straight pipe part and forms a part of a first spherical body having a predetermined spherical curvature and a smooth outer surface;
a second connecting structure portion including a second straight pipe portion and a second curved body connected to one end of the second straight pipe portion, the second curved body forming a part of a second spherical body having substantially the same spherical curvature as the spherical curvature of the first curved body, and a second fitting portion having a diameter substantially the same as the diameter of the outer surface of the first curved body and a smooth inner surface;
the first and second fitting portions each have a spherical diameter larger than the diameters of the first and second straight pipe portions, and are fitted to each other so that the first fitting portion is housed inside the second fitting portion , and the first and second fitting portions are fitted to each other so that their spherical centers coincide with each other, and the two fitting portions are configured to be capable of sliding and rotating relative to each other in a watertight manner;
the central axes of the first and second straight pipe portions are eccentrically disposed so as not to pass through the spherical centers of the first and second fitting portions;
In a side cross-sectional view taken along a first plane formed by the spherical center and the central axis of the first or second straight pipe portion, a part of an inner surface of the first or second straight pipe portion and at least a part of an inner surface of the first or second fitting portion form a continuous flat surface portion;
Moreover, the end peripheral portion of the first fitting portion is
in a side cross-sectional view taken along a first plane formed by the first spherical center and the central axis of the first straight pipe portion, the first spherical center and the first straight pipe portion are connected to a reference plane inside the first sphere formed on a second plane perpendicular to the first plane, the second plane including a straight line connecting the first spherical center and the center line of the first straight pipe portion and set at an angle of 38 degrees to 68 degrees with the center line portion, the first spherical center and the first straight pipe portion are formed in a position spaced from the reference plane by a length of 15 to 30% of the maximum diameter length of the spherical portion formed on the reference plane in a direction opposite to the side to which the first straight pipe portion is connected,
On the other hand, the end peripheral portion of the second fitting portion is
In a side cross-sectional view taken along a third plane formed by the second spherical center and the central axis of the second straight pipe section, the second spherical center is formed on a fourth plane perpendicular to the third plane, the fourth plane including a straight line connecting the spherical center and the center line of the second straight pipe section and forming an angle with the center line within a range of 38 degrees to 68 degrees;
Furthermore, an engagement protrusion is formed on the outer peripheral surface of the peripheral portion of the second connection structure, the engagement protrusion being configured such that a plurality of helical protrusions or helical grooves having at least a predetermined length are adjacently arranged at predetermined intervals along the outer peripheral surface and surrounding the peripheral portion,
On the other hand, at a portion where the first and second fitting portions of the first and second connection structures are fitted to each other, a ring-shaped reinforcing support is provided so as to cover the mutually fitting portion,
the reinforcing support is composed of an upright annular cylindrical portion having a predetermined height and formed with a predetermined thickness having an outer diameter larger than an outer diameter of the fitting protrusion provided on the peripheral edge of the second connection structure portion, and a truncated hollow cone-shaped portion connected to an upper portion of the upright annular cylindrical portion and formed integrally therewith;
a first annular recess formed on an inner peripheral surface of the upright annular cylindrical body portion with a predetermined height from a lower end surface of the upright cylindrical body portion toward an upper side, the first annular recess formed to be capable of fittingly engaging with at least a part of the outer peripheral edge portion and/or the fitting protrusion of the second connecting structure portion ;
Furthermore, a groove or a protrusion is disposed on an inner wall of the first annular recess, the groove or protrusion being capable of slidingly engaging with the helical protrusion or the helical groove formed on the outer surface of the fitting protrusion,
On the other hand, the truncated hollow conical portion has an outer peripheral surface formed of an inclined surface having a predetermined angle with respect to the vertical central axis of the reinforcing support, and the inner peripheral surface of the truncated hollow conical portion has a spherical curvature substantially the same as the spherical curvature of the outer surface of the first fitting portion of the first connecting structure portion, so that the inner peripheral surface of the truncated hollow conical portion and the spherical outer surface of the first fitting portion can slide and rotate relative to each other in a watertight manner ,
Moreover, the overall height of the reinforcing support is set to a height equivalent to a length of 15 to 25% of the maximum inner diameter of the peripheral edge portion formed on the fourth plane passing through the center point of the second spherical portion in the second fitting portion of the second connection structure portion,
a first insertion hole portion having a predetermined length extending upward from the lower end surface of the fitting protrusion at a portion of the lower end surface of the fitting protrusion corresponding to a position where the continuity of the arrangement of the plurality of helical protrusions or helical grooves formed on the outer peripheral surface of the fitting protrusion is interrupted; and a second insertion hole portion having a predetermined length extending upward from the lower end surface of the reinforcing support at a portion of the lower end surface of the reinforcing support corresponding to a position where the continuity of the arrangement of the plurality of helical protrusions or helical grooves formed on the outer peripheral surface of the fitting protrusion is interrupted;
Furthermore, a locking device is integrally formed on a predetermined base portion such that a first plug pin portion formed on the base portion so as to be able to be fitted and inserted into the first insertion hole portion and a second plug pin portion formed so as to be able to be fitted and inserted into the second insertion hole portion are parallel to each other, and is configured to prevent relative movement between the second connection structure portion and the reinforcing support body by simultaneously inserting the first and second plug pin portions into the first and second insertion holes, respectively.
Furthermore, in the first connection structure, a stopper portion consisting of a continuous protrusion having an annular shape is provided on the outer surface of the spherically curved surface portion of the first fitting portion, the stopper portion being configured to pass through both a first outer surface portion adjacent to the joint boundary of the spherically curved surface portion of the first fitting portion corresponding to a portion at the joint boundary with the first straight pipe portion where the length between the edge portion of the first straight pipe portion and the joint boundary is shortest, measured in a direction parallel to the central axis of the first straight pipe portion, and a second outer surface portion adjacent to the joint boundary of the spherically curved surface portion of the first fitting portion corresponding to a portion at the joint boundary with the first straight pipe portion where the length between the edge portion of the first straight pipe portion and the joint boundary is longest,
Furthermore, in the first outer surface region, a stopper portion cutout portion is formed in accordance with a change in the wall thickness or outer diameter of the first straight tube portion, the cutout portion being formed with a length of 20 mm or less in each direction along the longitudinal axis of the stopper portion and centered on a portion of the stopper portion facing the first outer surface region,
Furthermore, in the second outer surface region, the portion of the stopper portion facing the second outer surface region is configured to be set at any position between the same basic arrangement position as the second outer surface region and an arrangement position a predetermined distance away from the basic arrangement position, depending on changes in the thickness or outer diameter of the first straight pipe portion. The universal joint for fluid passages according to claim 1, characterized in that a second annular recess having a desired height and depth is formed in the annular inner wall surface of the reinforcing support part where it abuts and joins with the upper surface of the outer circumferential edge of the second fitting part of the second connection structure part, and a desired annular packing material is stored inside the second annular recess. The universal joint for fluid passages according to claim 2, characterized in that the annular packing material is made of silicone resin, and the inner wall surface of the annular packing material has at least one recessed annular groove formed with a predetermined depth along the longitudinal direction of the annular packing material from the surface of the inner wall surface of the annular packing material toward the outer wall surface of the annular packing material.

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