JP4378470B2 - Housing type pipe fitting - Google Patents

Description

  The present invention is applied to various pipes such as water supply, fire extinguishing, cooling water, cold / hot water, and drainage. A gasket is fitted to both ends of pipes to be joined, a housing is covered from above, and a fluid is tightened by a bolt / nut tightening means. In particular, the housing type has a groove-type joint structure in which a circumferentially continuous annular groove is formed on the outer periphery of the end of the pipe to prevent detachment. It relates to pipe joints.

  As this type of housing-type pipe joint, those disclosed in Patent Document 1 and Patent Document 2 are known. The housing-type pipe joint disclosed in Patent Document 1 has a substantially semicircular convex engaging portion and a concave engaging portion that fit each other on seating surfaces facing each other when the pipe is mounted on a pair of housings. The housing is distributed and formed so as to be laterally displaced with respect to the center line of the housing (a line in a direction perpendicular to the longitudinal direction of the pipe). For this reason, when a pair of housings are tightened to the end of the pipe using bolts and nuts, the positioning between the convex engagement part and the concave engagement part makes it possible for the housings to move sideways (pipe length (In the hand direction), they are fixed while being displaced from each other.

  The housing-type pipe joint disclosed in Patent Document 2 is a protrusion that protrudes in the lateral direction (in the longitudinal direction of the pipe) within a predetermined angular range in the circumferential direction on both ends of a pair of semicircular arc-shaped tightening portions in the housing. Is integrally formed in a state of projecting in opposite directions at each end in the circumferential direction. According to this configuration, as the bolts and nuts are tightened and attached to the pipe end portions of the pair of housings, the projecting portions projecting inward and outward move toward the side wall of the annular groove.

  That is, these Patent Documents 1 and 2 function so that the backlash in the groove width direction (pipe longitudinal direction) between the annular groove and the tightening portion is eliminated as the housing is tightened with bolts and nuts. Yes, due to its function, when pipe thrust or thermal expansion / shrinkage occurs due to internal pressure, the pipe and the pipe joint move relatively in the longitudinal direction of the pipe, that is, the connection between pipes using a housing-type pipe joint The portion has the advantage that the disadvantage of lack of rigidity can be reduced.

Although it is a housing type pipe joint having various advantages as described above, it is considered that the connection cannot be performed well depending on the dimensional accuracy of each part and accumulation of errors. In other words, if the inner diameter of the housing (inner diameter) is finished smaller than the diameter (outer diameter) of the annular groove, or if the position of the housing end face is more than necessary on the mating housing, it will be opposed via a gasket. Even if the pipe ends are covered with a pair of housings and tightened with bolts and nuts, the gaskets cannot be compressed sufficiently, or there is a gap between the annular groove and the part that fits into the annular groove in the housing. There is a risk of inconvenience that it cannot be done. As described above, there is still room for further improvement in connecting the pipes with sufficient strength using the housing-type pipe joint.
Japanese Patent No. 2538261 JP-A-11-241793

  The object of the present invention is to provide a gasket in a mounted state in which the housings are forcibly pressed toward each other regardless of component dimensional errors, product errors, or a combination of them, mainly due to structural improvements of the housing. Therefore, an improved housing-type pipe joint is realized and provided so that the pipes can be sufficiently compressed and the pipes can be firmly connected to each other without insufficient strength to improve the quality.

According to the first aspect of the present invention, a ring-shaped gasket 2 is externally fitted so that the ends Kt of a pair of pipes K having an annular groove 5 on the outer periphery of the end Kt straddle both ends Kt, Kt. Flange claws 9 having inner peripheral end portions 9t and 10t that can be fitted into the annular grooves 5 and 5 on both sides of the space portion 6 in which the gasket 2 is arranged so as to face and connect in a sealed state. , 10 is formed in a substantially U-shaped cross-section, and the housing 1 is forced into a pair of housings 1 having a substantially semicircular shape, and the housings 1 and 1 are forced toward each other. A housing-type pipe joint comprising maintenance means I capable of being maintained;
In a state in which both end faces 8a, 8a of the pair of housings 1, 1 are in contact with each other, the housing width formed by connecting the inner peripheral surfaces 9a, 10a of the pair of housings 1, 1 respectively. In the direction of the loop, the diameter Ra in the housing opening direction is slightly larger than the maximum diameter Dmax within the allowable dimension error range of the annular groove 5, and the diameter Rb in the housing depth direction is the allowable dimension of the annular groove 5. It is formed in a substantially elliptical shape slightly smaller than the minimum diameter Dmin within the error range.

The invention according to claim 2 is the housing type pipe joint according to claim 1,
The inner peripheral surfaces 9a and 10a are formed as inclined surfaces that are inclined with respect to a reference line Z that is the center in the width direction of the housing 1 over the entire length or almost the entire length of the inner peripheral end portions 9t and 10t. And
In each of the end portions in the circumferential direction of the pair of housings 1, 1, a concave portion 16 and a convex portion 17 that can be positioned relative to each other by being fitted to each other are formed. ,
The pair of housings in a fitting state in which the concave portion 16 and the convex portion 17 are fitted to each other by setting the concave portion 16 in the housing width direction to be longer than the convex portion 17 in the housing width direction. The relative position adjusting means B is provided which can be moved by shifting the relative positions of 1 and 1 in a twisting direction, and which allows the maintaining means I to function in the shifted and moved state. It is a feature.

  According to a third aspect of the present invention, in the housing type pipe joint according to the second aspect, the width h of the inner peripheral surfaces 9a, 10a is smaller than the minimum width of the annular groove 5 and constant in the circumferential direction. It is characterized by being set to the state which becomes.

The invention according to claim 4 is the housing-type pipe joint according to claim 2 or 3, wherein the maintaining means I is a bolt insertion hole of the mounting piece 7 formed at each of both circumferential ends of the housing 1. 11 and a bolt 3 and a nut 4 that can be screwed through the bolt insertion holes 11 and 11 of the mounting pieces 7 and 7 in the fitted state,
The relative position adjusting means B includes a configuration in which the bolt insertion hole 11 is set to have a size that is flexible at a bolt passing position in the housing width direction.

  According to a fifth aspect of the present invention, in the housing-type pipe joint according to the fourth aspect, the surface 7a on the mating housing side of the mounting piece 7 is set at a position where the surface 7a recedes from the end surface 8a in the circumferential direction of the housing 1. It is characterized by that.

  According to the first aspect of the present invention, as will be described in detail in the section of the embodiment, it is avoided that the housing end faces come into contact with each other and the force by the maintaining means, for example, the tightening torque is prevented from reaching a peak, and the bolts and nuts are used. The force for maintaining the pressure between the housings by the maintaining means can be used effectively as the compressive force of the gasket regardless of its strength, and a good sealing performance can be obtained by compressing the gasket. As a result, the gaskets are fully compressed in a mounted state where the housings are forced to approach each other, regardless of component dimensional errors, product errors, or a combination of them, mainly due to structural improvements in the housing. Thus, an improved housing-type pipe joint can be provided so that the pipes can be firmly connected without lack of strength and the quality can be improved.

  Incidentally, the pipe joints disclosed in the above-mentioned Patent Documents 1 and 2 also have the following problems. That is, the above two kinds of technologies (Patent Documents 1 and 2) should improve the connection rigidity of the connection connection part of the pipes using the housing-type pipe joint, but the effect is effectively obtained in practice. There was nothing. The cause is as follows. The means for producing the annular groove formed at the end of the tube is roughly divided into those by rolling and those by cutting. FIG. 11 (a) shows the annular groove 5 formed by rolling. . The annular groove 5 by rolling is a method of making the tube wall to be deformed to the inner diameter side by using a roll processing machine (not shown), and the groove opening width groove d1 is larger than the groove bottom width d2 (d1> d2 ) The left and right side peripheral walls 5a and 5b are inclined tapered walls, the corner 5d between the groove bottom 5C and the left and right side peripheral walls 5a and 5b, and the left and right side peripheral walls 5a and 5b and the pipe outer peripheral surface Kb. Each of the corners 5e has a rounded shape (corner R, corner R).

  FIG. 11B shows an annular groove 5 formed by cutting. Since the annular groove 5 formed by cutting is formed by scraping the tube wall Kc from the tube outer peripheral surface Kb, the groove bottom 5c and the left and right side peripheral walls 5a and 5b are almost completely flat and have corners 5d. The corner 5e is not rounded, but is formed into a right angle (so-called pin corner or pin angle). Although the annular groove 5 by this cutting increases in cost, it can be finished to a dimension as designed with excellent processing accuracy and less error, whereas the annular groove 5 by rolling described above is for rolling. Although dimensional errors and product errors due to roll wear and the like tend to be relatively large, the processing cost is low and the productivity is excellent.

  The pipe joints shown in Patent Documents 1 and 2 are based on the premise that the annular groove is created with the desired dimensional accuracy. However, in actuality, there are both rolling and cutting. Even with the techniques disclosed in Patent Documents 1 and 2, rattling between the annular groove and the pipe joint is not eliminated, and in some cases, the connection rigidity is inferior. As described above, there is still room for improvement with respect to increasing the connection rigidity between the pipes in the housing-type pipe joint.

Therefore, if the invention of claim 2 is used, the following effects can be obtained. In other words, as will be described in detail in the section of the embodiment, by adopting a structure in which a pair of recesses and projections fit together, positioning at the time of assembly with a pair of housings fitted on a pipe is easy and reliable. The inner circumferential surface of the pair of flange claws is relative to the reference line, which is the center line of the housing, regardless of the relatively large dimensional error of the annular groove due to rolling, etc. As the inclined surface, the rear end of both weekly reports of the inner peripheral end of the flange claw and the side peripheral wall of the annular groove are brought into contact with each other at a gentle angle so that the pipes are sealed more firmly and tightly than before. A housing-type pipe joint that can be connected and connected can be realized. In other words, it is possible to avoid rattling between the housing and the annular groove regardless of the groove forming method such as rolling or cutting, and the connection rigidity between the pipes can be increased and the quality can be improved. An improved housing-type pipe joint can be provided.
Then, it is avoided that the housing end faces come into contact with each other, and the force by the maintaining means, for example, the tightening torque is prevented from reaching a peak, and the force to keep the housings pressed by the maintaining means such as bolts and nuts is maintained regardless of the strength. In addition, the gasket can be effectively used as the compression force of the gasket, and there is an advantage that a good sealing property can be obtained by compression of the gasket.

  As a result, in addition to the above-described effects of the invention of claim 1, it is possible to avoid rattling between the housing and the annular groove regardless of the groove forming method such as rolling or cutting, and the connection rigidity at the connection portion between the tubes. As a result, it is possible to provide an improved housing-type pipe joint that can improve the quality by increasing the number of holes.

  According to the invention of claim 3, even if the dimensional error of the groove width of the annular groove is large, the contact angle conditions between the side peripheral walls on both sides of the annular groove and the flange claws are kept in the same state. There exists an advantage which can acquire the said effect by 2. FIG.

  According to the invention of claim 4, in addition to any of the above-described effects of claim 2 or 3, a reasonable maintaining means which functions to pull down the housings by bolts and nuts and which functions reliably at low cost. A simple structure that allows the bolt insertion holes formed in the mounting pieces at both ends of the housing to be set to a size that is flexible at the bolt passage position in the housing width direction, such as a fool hole or a long hole, for example. Accordingly, it is possible to provide a housing-type pipe joint having an advantage that the above-described effect (reasonable maintenance means) can be exhibited regardless of the twisting movement of the housings.

  According to the invention of claim 5, in addition to the above-described effect of the invention of claim 4, there is a disadvantage that the attachment pieces are deflected and displaced and the attachment pieces facing each other come into contact with each other due to an increase in the tightening force torque of the bolts and nuts. Since this does not occur, the tightening force of the bolts and nuts can be effectively utilized as a force for pressing the pair of housings together, and the housing-type tube that realizes a rigid connection connection state in a sealed state between the pair of tubes A joint can be provided.

  Embodiments of a housing type pipe joint according to the present invention will be described below with reference to the drawings. 1 is an exploded perspective view of a housing-type pipe joint, FIG. 2 is a cross-sectional view of an annular groove portion, FIG. 3 is a side view of a pair of housings superimposed, FIG. 4 is a perspective view of a single housing, FIG. 5 is a developed view of the inner peripheral side of the housing, FIGS. 6 to 9 are side views showing the engagement state of the housing and the annular groove in the standard state, the narrow state, the wide state, and the special wide state, respectively. FIG. FIG. 11 is a diagram showing an annular groove for each production means.

[Example 1]
As shown in FIGS. 1 to 3, the housing-type pipe joint A according to the first embodiment is means for connecting and connecting a pair of opposed pipes K and K in a sealed state, and is a pair of identical housings 1. , 1, a ring-shaped gasket 2, and two sets of bolts 3 and nuts 4. That is, the end portions Kt of a pair of pipes K having the annular groove 5 on the outer periphery of the end portion Kt are abutted with each other in a state in which the gasket 2 is externally fitted so as to straddle both end portions Kt and Kt. In order to connect and connect in a sealed state, an inner peripheral end portion that can be fitted into the annular groove 5 on both sides of the space portion 6 where the gasket 2 is positioned (accommodated) (an example of “can be fitted”). The cross-section in which the flange claws 9 and 10 having 9t and 10t are formed is substantially U-shaped, and the overall shape is a substantially semicircular shape, and the housings 1 and 1 are in a direction to approach each other. The housing-type pipe joint A is configured to have a maintenance means I that can freely maintain the forcedly pressed state (an example of “maintainable”). The maintenance means I includes a bolt 3 and a nut 4 that can be screwed together (an example of “possible”).

  As an example of the end treatment of the tube K, the annular groove 5 formed by rolling (or cutting) at the end Kt has a groove width d of 8.1 mm (more precisely, the groove opening width d1 is 8.7 mm and the groove bottom width d2 is 7.5 mm), and the distance c from the outer end of the annular groove 5 on the tube end Ka side to the tube end Ka is set to 15.9 mm. [See also FIG. 11 (a)]. The outer diameter of the tube K is generally 2 to 6 inches. The gasket 2 is a general self-sealing type having a cross-sectional lip groove shape and an overall shape formed in a ring shape, and is made of synthetic rubber or the like.

  As shown in FIGS. 1 to 6, the housing 1 includes a substantially semicircular web 8, a pair of flange claws 9, 10 integrally formed in a state extending from both sides in the width direction of the web 8 to the inner diameter side, and the web A portion surrounded by the left and right flange claws 9 and 10 and the web 8 is formed in the space portion 6. Both end faces 8a, 8a in the circumferential direction of both webs 8 are surfaces defined as a part of a virtual horizontal plane parallel to the housing axis (same as the axis of the tube K) P, and the assembly shown in FIG. In the state, the mounting pieces 7 and 7 projecting in the outer diameter direction with respect to the housing shaft center P so that a space is formed between the mounting pieces 7 and 7 facing each other. The surface 7a is formed so as to be clearly retreated from the corresponding end surface 8a (from the virtual horizontal plane). Further, each attachment piece 7 is formed with a bolt insertion hole 11 having a long hole shape that is long in the tube longitudinal direction.

  The inner peripheral surfaces 9a and 10a of the flange claws 9 and 10 extend in the width direction of the housing 1 (arrows in FIGS. 5 and 6) over the entire length (or almost the entire length) in the circumferential direction of the inner peripheral ends 9t and 10t. (B), it is inclined at an angle θ with respect to a reference line Z which is the center and has a constant width with a width h. The housing 1 in FIG. 5 shows a state in which the inner portion including the inner peripheral surfaces 9a and 10a is developed in a flat shape. In this development view and FIG. It is a line connecting the central points of the bolt insertion holes 11 to be formed.

  The left and right outer peripheral surfaces 12, 12 of the housing 1 are outer diameter side surfaces 12 a, 12 a that are inclined with respect to the housing axis P and inclined with respect to the housing axis P in a narrowing direction. The inner side surface (an example of a “side peripheral surface portion”) 12b and 12b, and the ridgelines e and e, which are boundaries between the inner and outer side surfaces 12a and 12b, are viewed from the side (in the radial direction with respect to the housing axis P). Is set to be parallel to the reference line Z. Therefore, as shown in FIG. 5, each inner peripheral surface 9a, 10a can be defined as a surface (inclined surface) having an angle θ inclination and a width h with respect to the ridge line e in a side view. The outer edge f of the inner peripheral surfaces 9a and 10a is an inner portion of a line segment connecting one point on the ridge line e, which is an arc (or substantially arc) centered on the housing axis P, and the housing axis P. It is formed by gradually changing the orientation (inward in the housing width direction) angle β in the circumferential direction.

  That is, the inclination angle β with respect to the ridge lines e and e of the left and right outer peripheral surfaces 12 and 12 is one end (on the left inner peripheral surface 9a in FIG. 5, the lower end on the paper surface, and on the right inner peripheral surface 10a on the upper paper surface). End) is gradually increased linearly (decrease as viewed from the other end side) over a small angle close to 0 degrees (possible with a draft angle of the mold) and a large angle at the other end, The surface surrounded by the ridge line e and the outer edge f is the aforementioned inner diameter side surface 12b. Further, the inner peripheral surfaces 13 and 13 of the inner peripheral end portions 9t and 10t are formed as surfaces having a small angle such as the draft angle from the inner end edges g of the inner peripheral surfaces 9a and 10a. The space portion 6 is a portion surrounded by side peripheral walls 14 and 14 that are slightly inward from the left and right inner peripheral surfaces 13 and 13 and an inner peripheral wall 15. It is advantageous to form it smaller than the size of the gasket 2 so that it can be compressed to improve the sealing performance.

  A concave portion 16 and a convex portion 17 are fitted and formed on the end surfaces 8a and 8a, which are end portions in the circumferential direction of the pair of housings 1 and 1, so as to fit with each other in the assembled state and perform relative positioning. is there. The recess 16 has a side wall 16 a, 16 a corresponding to the side peripheral wall 14, 14 and a back wall 16 b corresponding to the inner peripheral wall 15, and the convex portion 17 corresponds to the side peripheral wall 14, 14. The side protrusions 17a and 17a and the main protrusion 17b corresponding to the inner peripheral wall 15 are formed into substantially U-shaped protrusions. As shown in FIGS. 5, 6, etc., the concave portion 16 is formed slightly larger than the convex portion 17. Specifically, in the fitting state in which the convex portion 17 is inserted into the concave portion 16, there is a clear lateral gap s1 between the side wall 16a and the side protrusion 17a, and the back wall 16b and the main protrusion 17b. A slight vertical gap s2 is formed between them (s1 ≧ s2).

  Thus, the dimension of the recess 16 in the housing width direction is set to be longer than the dimension of the protrusion 17 in the housing width direction, and the pair of housings 1 in a fitting state in which the recess 16 and the protrusion 17 are fitted with each other. The relative position adjusting means B is provided which can shift the relative positions of the two in a twisting direction and allows the maintaining means I to function in the shifted and moved state. That is, as shown in FIG. 6 and the like, the pair of bolt insertion holes 11, 11 are threaded in the housing width direction (in the direction of arrow B and coincides with the tube axis direction when assembled to the tube K). The relative position adjusting means B is established by the configuration in which the long hole having a size that is flexible in position and the configuration in which the concave portion 16 is longer than the convex portion 17 in the housing width direction.

  As shown in FIGS. 2, 7, and 8, this passes through the intersection of the housing axis P and the reference line Z and is orthogonal to the above-described virtual horizontal plane (orthogonal to both the housing axis P and the reference line Z). It is a means that enables the housings 1 and 1 to be rotated relative to each other around the rotational axis X, which is an axial center, so that they can be displaced from each other. The bolt 3 and the nut 4 are used even in the twisted state. It is possible to attach and fix to the pipe K as a pipe joint. The direction of rotation (twisting direction) can be rightward (in the direction of arrow C in FIG. 6) or leftward (in the direction of arrow D in FIG. 6). As will be described in detail later by the relative position adjusting means B, when the width of the annular grooves 5 and 5 is narrower or wider than the standard width, the housings 1 and 1 are slightly twisted to move the flange claws. Both end portions in the circumferential direction of 9 and 10 are brought into contact with the left and right peripheral walls 5a and 5b of the annular grooves 5 and 5, and the housing type pipe joint A can be assembled and mounted in a state of high rigidity.

  As shown in FIGS. 2 and 3, in the fitted state, the loop shape in the housing width direction formed by connecting the inner peripheral surfaces 9a and 10a of the pair of housings 1 and 1 to each other, The diameter Ra in the housing opening direction is slightly larger than the maximum diameter Dmax within the allowable dimensional error range in the diameter D of the groove bottom 5c of the annular groove 5, and the diameter Rb in the housing depth direction is the diameter of the groove bottom 5c of the annular groove 5. It is formed in a substantially elliptical shape slightly smaller than the minimum diameter Dmin within the allowable dimensional error range in the diameter D (see particularly FIG. 3B). With such a dimension setting, as shown in FIG. 2A, in a state where the pair of housings 1, 1 are fitted and attached to the annular groove 5, the opening portions of the inner peripheral surfaces 9 a, 10 a are always formed in the annular groove 5. The innermost surfaces 9a, 10a are in contact with the groove bottom 5c without being supported by the groove bottom 5c, and a clear gap is formed between the oppositely disposed end faces 8a, 8a. ing.

  In the mounted state shown in FIG. 2 (a), the gap between both end faces 8a and 8a is defined as the first gap n1, and the gap between the bottom surface 16d of the concave portion 16 and the top surface 17d of the convex portion 17 is defined as the second gap n2. For example, the three dimensions of the first and second gaps n1 and n2 and the longitudinal gap s2 between the back wall 16b and the main projection 17b are set so that the relational expression s2 ≦ n1 <n2 is established. Is good. The grounds are as follows. First, when tightening with the bolt 3 and the nut 4, the end faces 8a and 8a must be brought into contact with each other, so that n1 <n2 is derived. Next, it is necessary that n1> 0 in order to exert the tightening force by the bolt 3 and the nut 4 freely. Further, the vertical gap s2 that is a radial gap with respect to the axis P between the concave portion 16 and the convex portion 17 that does not significantly affect the twisting movement of the housing is preferably as small as possible for the purpose of positioning the housings 1 and 1. Thus, the above-described relational expression is obtained.

  Next, the mounting state of the housing type pipe joint A when the groove width of the annular groove 5 of the pipe K is variously different will be described. The annular groove 5 formed by rolling, which is excellent in productivity, has a property in which the dimensional tolerance of the groove width is relatively large and the corner R and the corner R are attached. FIG. 6 shows a state where the groove width is narrower than a reference value, FIG. 7 shows a state where the groove width is narrower than the reference value, FIG. 8 shows a case where the groove width is wider than a reference value, and FIG. And Here, for simplicity, the reference value of the groove width is j, and the actual groove width is d. The groove width d is an arithmetic average value of the groove opening width d1 and the groove bottom width d2 [d = (d1 + d2) / 2].

  First, as shown in FIG. 6, the standard state is when the groove width d of the annular groove 5 formed at a distance c away from the tube end Ka is as a reference value (d = j). In this standard state, the reference line Z of the housing 1 coincides with the direction (arrow A direction) perpendicular to the axis P (= housing axis) of the tube K and the circumferential direction of the annular groove 5. Thus, only the circumferential ends of the inner peripheral end portions 9t and 10t are in contact with the side peripheral walls 5a and 5b of the annular groove 5. That is, the inner peripheral surfaces 9a and 10a of one housing 1 drawn by a solid line in FIG. 6 and the inner peripheral surfaces 9a and 10a (shown by broken lines) of the other housing are viewed in the direction of the rotation axis X. The ridgelines e and e of the outer peripheral surfaces 12 and 12 of the housings 1 and 1 match each other and can be seen as one line. Further, the bolt 3 as the maintaining means I is located in the center in the right and left direction of the bolt insertion hole 11 (in the housing width direction and in the direction of arrow B), and the convex portion 17 is in the left and right direction of the concave portion 16 (housing In the width direction and in the direction indicated by arrow B), it is located in the center.

  Therefore, when viewed from the direction of the rotation axis X, the pair of housings 1 and 1 are mounted with the ridgelines e and e just overlapping each other and tightened with the bolts 3 and nuts 4 and assembled to the tubes K and K. If this is done, the inner back portions of the inner peripheral surfaces 9a, 10a of the housings 1, 1 are in contact with the groove bottoms 5c, and are in contact with the left and right side peripheral walls 5a, 5b. The pipes K and K are connected and connected in a sealed state in a rigid state (stiff state) with no play. That is, in this case, the twist angle around the rotation axis X between the housings 1 and 1 is 0 degree.

  Therefore, when the thrust or thermal expansion / contraction of the pipe K due to internal pressure occurs, the pipe K and the pipe joint A try to move relative to each other in the longitudinal direction of the pipe, or the pipe K and the pipe K tend to bend each other and be displaced. It is possible to sufficiently withstand the force to be applied. Therefore, it is possible to omit a pipe support means in the vicinity of a dedicated pipe joint such as hanging and supporting the pipe K at a plurality of positions before and after the pipe joint A. Compared to the conventional case, the arrangement space of the pipe, the structure is simplified, and the cost is reduced. Thus, the housing type pipe joint A that is advantageous in all aspects can be realized.

  For reference, the relationship between the annular groove 5 and the inner peripheral end 9t of the flange pawl 9 in the standard state is shown in FIG. If the reference line Z is assembled in a normal state perpendicular to the axis P of the tube K by the inner peripheral surface 9a inclined with respect to the reference line Z (ridge line e), the inner peripheral end 9t of the inner peripheral end 9t is in that state. It can be understood that both end portions are just in contact with the corresponding side peripheral walls 5a and 5b and fit in the groove width direction (arrow B direction) without backlash. That is, the ridgelines e and e in the direction of the rotation axis X are in a standard (reference) assembled state in which the center points of the pair of bolt insertion holes 11 and 11 of the housings 1 and 1 match each other. There is a convenience that can be confirmed by visual inspection.

  Next, when the groove width of the annular groove 5 is narrow and the pair of housings 1 and 1 are in the same relative twist posture as in the standard state (see FIG. 6), the inner peripheral surfaces 9a and 10a are inclined. Accordingly, the circumferential end portions of the inner peripheral end portions 9t and 10t protrude beyond the narrow groove width of the annular groove 5, and cannot be fitted into the annular groove 5 as they are. Therefore, as shown in FIG. 7, the angle of the inner peripheral surfaces 9a, 10a with respect to the groove center of the annular groove 5 (the angle with respect to the direction of the arrow A which is perpendicular to the tube axis P) is determined from the inclination angle θ with respect to the reference line Z. Thus, the housings 1 and 1 are rotated (twisted) about the rotation axis X in the direction of decreasing.

  In FIG. 7, the housing 1 arranged on the other side of the tube K indicated by the phantom line is twisted and moved at an angle α in the direction of the arrow D with respect to the reference line Z ′ in the standard state, and before the tube K. The located housing 1 (shown by a broken line) is twisted and moved at an angle α in the direction of the arrow C with respect to the reference line Z in the standard state. Accordingly, the relative twist movement angle between the housings 1 and 1 that have been twisted is 2α. At this time, the bolt 3 moves by an angle α around the rotation axis X with respect to the bolt insertion hole 11 of the housing 1 drawn by a solid line, but on the near side drawn by a broken line. Since it moves to the opposite side with respect to the housing 1, the movement amount is canceled out.

  Therefore, even if the pair of housings 1 and 1 are twisted and moved, the absolute position of the bolt 3 theoretically does not move from the original position (position on the reference line Z 'in the standard state). The convex portion 17 existing in the concave portion 16 can be moved by the twist angle 2α without difficulty due to the presence of the lateral gap s1 described above. Actually, the housings 1 and 1 are twisted and moved in a state where the bolt 3 and the nut 4 are loosely temporarily tightened, and then the bolt 3 and the nut 4 are finally tightened. As a result, even when the groove width of the annular groove 5 is narrowed due to a large error that cannot be performed by cutting, the housing type pipe joint A according to the present invention rigidly connects and connects the tubes K and K in a sealed state. Thus, the above-described operational effects in the standard state can be exhibited equally.

  For reference, the relationship between the annular groove 5 and the inner peripheral end 9t of the flange claw 9 in the narrow state is shown in FIG. 10A as exaggerated and simplified. By assembling the housing 1 (not shown) by twisting and moving it in the direction of the arrow D at an angle α, the inclination angle of the inner peripheral surface 9a with respect to the annular groove 5 becomes an angle (θ−α) smaller than θ in the standard state. Therefore, as in the case of the standard state, both end portions of the inner peripheral end portion 9t are just in contact with the corresponding side peripheral walls 5a and 5b, and can be stored without backlash in the groove width direction (arrow B direction).

  When the annular groove 5 is wide and wide, the pair of housings 1 and 1 have the same relative twisted posture as in the standard state (see FIG. 6). It does not reach the peripheral walls 5a and 5b, and a gap is formed in the direction of the pipe axis P, so that the pipe joint A cannot be assembled rigidly. Therefore, as shown in FIG. 8, the angle of the inner peripheral surfaces 9a, 10a with respect to the groove center of the annular groove 5 (the angle with respect to the direction of the arrow A which is perpendicular to the tube axis P) is determined from the inclination angle θ with respect to the reference line Z. Also, the housings 1 and 1 are rotated (twisted) about the rotation axis X in the direction of increasing.

  In FIG. 8, the housing 1 arranged on the other side of the tube K indicated by the phantom line is twisted and moved at an angle γ in the direction of the arrow C with respect to the reference line Z ′ in the standard state, and before the tube K. The located housing 1 (shown by a broken line) is twisted and moved at an angle γ in the direction of the arrow D with respect to the reference line Z in the standard state. Therefore, the relative twist movement angle between the housings 1 and 1 that have been twisted is 2γ. At this time, the bolt 3 moves about the rotation axis X by an angle γ with respect to the bolt insertion hole 11 of the housing 1 drawn by a solid line, but on the near side drawn by a broken line. Since it moves to the opposite side with respect to the housing 1, the movement amount is canceled out.

  Therefore, even if the pair of housings 1 and 1 are twisted and moved to the opposite side from the narrow state, the absolute position of the bolt 3 is theoretically the original position (on the reference line Z ′ in the standard state). It will not move from (position). The convex portion 17 existing in the concave portion 16 can be moved by the twist angle 2γ without difficulty due to the presence of the lateral gap s1 described above. Actually, the housings 1 and 1 are twisted and moved in a state where the bolt 3 and the nut 4 are loosely temporarily tightened, and then the bolt 3 and the nut 4 are finally tightened. As a result, even when the groove width of the annular groove 5 is widened due to a large error that cannot be performed by cutting, the housing-type pipe joint A according to the present invention rigidly connects and connects the tubes K and K in a sealed state. Thus, the above-described operational effects in the standard state can be exhibited equally.

  For reference, the relationship between the annular groove 5 and the inner peripheral end 9t of the flange claw 9 in the wide state is shown in FIG. By assembling the housing 1 (not shown) by twisting and moving it in the direction of the arrow C at an angle γ, the inclination angle of the inner peripheral surface 9a with respect to the annular groove 5 becomes an angle (θ + γ) larger than θ in the standard state. Therefore, as in the case of the standard state, both end portions of the inner peripheral end portion 9t are just in contact with the corresponding side peripheral walls 5a and 5b, and can be stored without backlash in the groove width direction (arrow B direction).

  Further, even when the groove width of the annular groove 5 is wide, the special distance that the distance from the tube end Ka of the side peripheral wall 5a on the tube end Ka side of the annular groove 5 is formed exactly according to the reference value. In some cases, the pair of housings 1, 1 can be in the same assembled state as the standard state shown in FIG. That is, as shown in FIG. 9, when the pair of housings 1 and 1 are twisted and the angle of movement is 0, that is, assembled to the tube K in a normal state, the inner surfaces 9a and 10a are inclined regardless of the inclination. A clear gap i exists in the direction of the tube axis P between the inner diameter side surface 12b of the peripheral end portions 9t and 10t and the side peripheral wall 5b far from the tube end Ka of the annular groove 5.

  However, one end of the inner peripheral surface 13 at the inner peripheral end portions 9t and 10t is in a state of just contacting the side peripheral wall 5a on the side close to the tube end Ka of the annular groove 5 without rattling, as in the standard state. Therefore, the pair of pipes K, K is tightly sealed without rattling by cooperating with the configuration in which the pipe ends Ka, Ka of the pair of pipes K are in close contact with each other without gaps. It can be connected. In the special case shown in FIG. 9, the tube ends Ka and Ka are in contact with each other. However, the standard state in FIG. 6, the narrow state in FIG. 7, and the general state in FIG. In each of the wide states, even if there is a slight gap between the pipe ends Ka, Ka, the housing-type pipe joint A of the present invention can be assembled rigidly.

  As described above, according to the housing-type pipe joint A according to the present invention, the inner peripheral surfaces 9a, 10a of the pair of flange claws 9, 10 pass through the center point of the pair of bolt insertion holes 11, 11. And a reference line Z that is a center line in the width direction as an angle and an inclined surface that is inclined at an angle θ with respect to a ridge line e that is a contour line in the width direction as viewed in the radial direction with respect to the housing axis P as the housing 1. The inner peripheral end portions 9t, 10t of the flange claws 9, 10 including the inner peripheral surfaces 9a, 10a are thereby formed so that the radial cross-sectional shape thereof has a width in the left-right direction (housing width direction) closer to the inner diameter side. The concave portion 16 and the convex portion 17 are formed so as to have a narrowed tapered shape, can be twisted together, and facilitate the assembly of the housings 1 and 1 which are the same parts. Mating with While employing the forming, by is provided with a gap required for both sides of the housing width direction with them recesses 16 and protrusions 17, it is possible to obtain the effects or advantages as follows.

  First, the inner peripheral surfaces 9a and 10a that are in contact with the groove bottom 5c of the annular groove 5 in the flange claws 9 and 10 have a width h smaller than the minimum groove width of the annular groove 5 of the pipe K in the circumferential direction. If there is a dimensional error in the annular groove 5, the inclination angle of the inner peripheral surfaces 9 a and 10 a with respect to the annular groove 5 is changed by a slight twisting movement of the housing 1. A state in which both end portions of the end portions 9t and 10t are in contact with the side peripheral walls 5a and 5b of the annular groove 5 can be obtained. As a result, the annular grooves 5 formed by rolling, which are slightly inferior in dimensional accuracy but advantageous in terms of productivity and cost, can be used for the pipes K and K and the housing 1 as compared with the conventional connecting connection using the housing type pipe joint. , 1 can be firmly assembled and fixed in a rigid state (rigid state) with no backlash in the longitudinal direction of the tube. In other words, the rigidity of the housing-type pipe joint part that connects and connects the pipes in a sealed state can be improved. For example, a structure that supports the pipes at multiple locations before and after the pipe joints using hoists and supports is unnecessary. Thus, the advantage of saving space and cost can be obtained.

  In this case, when the groove width of the annular groove 5 is narrower than the reference value, the inclination angle of the inner peripheral surfaces 9a and 10a with respect to the annular groove 5 is in the reference state (see FIG. 6 and FIG. 10B). The pair of housings 1 and 1 are twisted and moved in a direction having a smaller inclination angle (θ−α), and the inner peripheral side surfaces 12b of the inner peripheral end portions 9t and 10t and the peripheral end portions of the inner peripheral surface 13 are arranged on the corresponding side. It can be in a state of contacting the peripheral walls 5a and 5b [see FIG. 7 and FIG. 10 (a)]. When the groove width of the annular groove 5 is wider than the reference value, the inclination angle of the inner peripheral surfaces 9a, 10a with respect to the annular groove 5 is larger than that in the reference state (see FIG. 6 and FIG. 10 (b)). The pair of housings 1 and 1 are twisted and moved in a direction of an angle (θ + γ), and the inner peripheral side surfaces 12b of the inner peripheral end portions 9t and 10t and the peripheral end portions of the inner peripheral surface 13 are moved to the corresponding side peripheral walls 5a and 5b. It can be in a state of contact (see FIG. 8 and FIG. 10C). When the groove width of the annular groove 5 is the reference width, the inclination angle of the inner peripheral surfaces 9a, 10a with respect to the annular groove 5 is the inclination angle θ of the inner peripheral surfaces 9a, 10a with respect to the reference line Z (and the ridge line e). In this state, that is, when the twist angle of the housings 1 and 1 is 0 degree, the inner peripheral end portions 9t and 10t are connected to the inner peripheral surface 13b and the inner peripheral surface 13 in the circumferential direction. The state can be brought into contact with 5a and 5b (see FIG. 6 and FIG. 10B).

  At the time of twisting movement in both directions, the concave portion 16 and the convex portion 17 also rotate relative to each other, but the gaps s1, s1 provided on both sides of the concave portion 16 and the convex portion 17 in the housing width direction. Thus, the above-described twisting movement of the housings 1 and 1 is not hindered. Since the inclination of the inner peripheral surfaces 9a, 10a is a relatively gentle angle over the entire length in the circumferential direction or almost the entire length, the contact portions between the inner peripheral end portions 9t, 10t and the side peripheral walls 5a, 5b are in surface contact as much as possible. There is an advantage that the assembled state of the rigid pipe joint can be stably exhibited in a close state. Further, since the inclination angle between the inner peripheral surfaces 9a and 10a and the annular groove 5 is made the smallest when the groove width is narrow, the inner peripheral surfaces 9a and 10a and the annular groove when the groove width is the widest. The angle of inclination with the groove 5 can be suppressed so as not to become extremely large, and the above-mentioned advantages (the assembly state of the rigid pipe joint can be stably exhibited) can be enjoyed regardless of the narrow width of the annular groove. It is possible.

  Further, when the flange claws 9 and 10 are fitted in the annular grooves 5 and assembled to the tubes K and K, a state is set in which a gap is formed between the pair of opposing housing end faces 8a and 8a [FIG. 2 (a)], when the bolt 3 and the nut 4 are tightened strongly, the first contact portion with the groove bottom 5c is the central portion in the circumferential direction of the inner peripheral grooves 9a and 10a. Therefore, when a prescribed tightening force is applied, it can be effectively used as a force in the direction of tightening the gasket to improve the sealing performance. For example, in the structure in which the end faces 8a and 8a are in contact with each other first, if the tightening of the bolt 3 and the nut 4 is increased, the cut-off state in which the end faces 8a and 8a are in contact is prematurely increased, and the tightening torque is further increased. However, the inconvenience of not acting on the force for effectively tightening the gasket can be considered, but the housing type pipe joint according to the present invention does not cause such inconvenience.

An exploded perspective view showing a structure of a housing type pipe joint (Example 1) (A) Cross-sectional view showing the engagement structure between the housing and the annular groove, (b) Schematic diagram showing the actual engagement state between the inner peripheral surface of the housing and the annular groove (A) Side view in which housings are combined, (b) Schematic comparing the shapes of a pair of housing inner peripheral surfaces and circular grooves. Perspective view of single housing Development of the inner surface of the housing Side view showing the engagement structure between the housing and the tube when the annular groove is the reference value Side view showing the fitting state when the annular groove is narrower than the reference value Side view showing the fitting state when the annular groove is wider than the reference value Side view showing a special example of fittings when the annular groove is wider than the reference value The schematic diagram in which the angle of the engagement state between the inner peripheral surface and the annular groove is exaggerated is shown, (a) when the width of the annular groove is narrow, (b) when the width of the annular groove is standard, (c) the annular groove If the width is wide An annular groove at the end of the tube is shown, (a) is a rolled groove, (b) is a cutting groove.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Housing 2 Gasket 3 Bolt 4 Nut 5 Annular groove 6 Space part 7 Mounting piece 7a Surface (opposite surface) on the opposite housing side
9, 10 Flange claw 9a, 10a Inner peripheral surface 9t, 10t Inner peripheral end 8a End surface in the circumferential direction of the housing 11 Bolt insertion hole 12 Outer surface of the housing 12b Side peripheral surface portion 16 Recessed portion 17 Protruding portion e Side peripheral surface portion Edge f of outer diameter side of the outer edge f Outer edge edge of the inner peripheral surface on the outer side in the housing width direction h Width of the inner peripheral surface A Housing type fitting B B Relative position adjusting means Dmax Maximum within the allowable dimension error range of the annular groove Diameter Dmin Minimum diameter within the allowable dimensional error range of the annular groove I Maintaining means K Tube Kt End Ra Diameter in the housing opening direction Rb Diameter in the housing depth direction Z Reference line β Inclination angle of the peripheral surface portion

Claims (5)

In order to connect and connect the end portions of a pair of pipes having an annular groove on the outer periphery of the end portions so as to face each other in a sealed state with a ring-shaped gasket fitted over the both end portions. A pair of housings having a substantially U-shaped cross section in which flange claws having inner circumferential end portions that can be fitted into the annular groove are formed on both sides of a space portion where A housing-type pipe joint having maintenance means capable of maintaining a state in which the housings are forcedly pressed in a direction approaching each other,
In a state where both end faces of the pair of housings are in contact with each other, the loop shape in the housing width direction formed by connecting the inner peripheral surfaces of the flange claws in each of the pair of housings is the housing. The diameter in the opening direction is slightly larger than the maximum diameter within the allowable dimension error range of the annular groove, and the diameter in the housing depth direction is substantially elliptical slightly smaller than the minimum diameter within the allowable dimension error range of the annular groove. The formed housing type pipe joint. The inner peripheral surface is formed on an inclined surface that is inclined with respect to a reference line that is centered in the width direction of the housing over the entire length or almost the entire length of the inner peripheral end portion in the circumferential direction;
Each of the end portions in the circumferential direction of the pair of housings is formed by distributing a concave portion and a convex portion that are capable of relative positioning of the pair of housings by fitting with each other,
The dimension of the recess in the housing width direction is set to be longer than the dimension of the protrusion in the housing width direction, and the relative position of the pair of housings in the fitted state in which the recess and the protrusion fit together 2. The housing-type pipe joint according to claim 1, further comprising a relative position adjusting means that is movable in a twisting direction with respect to each other and that allows the maintaining means to function in the shifted and moved state.   The housing-type pipe joint according to claim 2, wherein the width of the inner peripheral surface is set to be smaller than the minimum width of the annular groove and constant in the circumferential direction. The maintaining means is a bolt that can be screwed through the bolt insertion holes of the mounting pieces formed at both ends in the circumferential direction of the housing and the bolt insertion holes of the mounting pieces in the fitted state. And a nut,
4. The housing-type pipe joint according to claim 2, wherein the relative position adjusting means includes a configuration in which the bolt insertion hole is set to have a size that allows the bolt insertion position in the housing width direction to be accommodated. 5.   The housing-type pipe joint according to claim 4, wherein a surface of the mounting piece on the side of the counterpart housing is set at a position retracting from an end surface in the circumferential direction of the housing.

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