CA1156286A

CA1156286A - Ball and socket type pipe coupling

Info

Publication number: CA1156286A
Application number: CA000363276A
Authority: CA
Inventors: Toshiyuki Sato
Original assignee: Suiken KK
Current assignee: Suiken KK
Priority date: 1979-10-26
Filing date: 1980-10-27
Publication date: 1983-11-01
Also published as: DE3040117C2; FR2468824B1; GB2066399B; FR2468824A1; JPS5666593U; JPS6329985Y2; DE3040117A1; GB2066399A

Abstract

ABSTRACT OF THE DISCLOSURE

A novel ball-and-socket-type pipe coupling is provided herein for interconnecting a first pipe with a second pipe. It includes a first socket housing fixedly mounted to an end of the first pipe; a second socket housing fixedly mounted to an end of the second pipe; each of the first and second socket housings having a spherical concave surface formed internally thereof; a single piece of joint pipe of simple cylin-drical construction having opposite free end sections; one of the free end sections extending into the first socket housing and the other of the free end sections extending into the second socket housing; a first ball member including an annular member mounted on the one of the free end sections and having a spherical outer surface disposed in spherically sliding contact with the concave surface of the first socket housing; and a second ball member including an annular member mounted on the other of the free end sections and having a spherical outer surface disposed in spheri-cally sliding contact with the concave surface of the second socket hous-ing. The joint pipe is angularly movable in accordance with spherical sliding movement of the first and second ball members with respect to the housing, while maintaining parallel relationship between the first and second pipes. Each of the first and second ball members includes a front end section including an annular projection extending radially in-wardly and having a first internal annular wall, a rear end section which is formed with an annular extension extending radially inwardly and having a second internal annular wall, and an annular hollow space ex-tending between the first and second internal annular walls. A first stop member is fixedly mounted on the one of the free end sections of the joint pipe and is disposed within the annular hollow space of the first ball center. A second stop member is fixedly mounted on the other of the free end sections of the joint pipe and is disposed within the annular hollow space of the second ball member, preferably also in its center.
The joint pipe is telescopically slidable in its axial directions with respect to the first and second ball members within a limited range.
The coupling is particularly advantageous when utilized in places where it is necessary to connect a pair of parallel pipe lines lying on two different planes or it is expected that a pair of connected pipe lines might be subjected to dislocation by an earthquake, subsiding of ground, or considerable weight, shocks or vibrations. The pipe coupling is also very useful in repairing such pipe lines that have been misaligned or actually affected by dislocation or subsiding of ground.

Description

This invention relates to a pipe coup]ing device, and more particularly to an improved ~all-and-socket-type pipe coupling.
Owing to subsiding of ground caused, for instance, by lowering of the water table, or dislocation of ground caused by an earthqlJake or any other reason, one of a pair of fluid-supplying pipe lines interconnected by a pipe coupling device is occasionally forced down to a new level lower than the level where the remainder pipe lines lies, causing damsge to the coupling device with a resulting leakage of fluid.
Conventional ball-and-socket-type pipe couplings as disclosed, for example, in Japanese Utility Model Laid-open No. 76515/79 is of such a type that one of a pair of pipes interconnected by the coupling is capable of axial and angular movement relative to the other pipe but is incapable of automatically establishing a new parallel relationship between the two centerlines thereof without losing the interconnection between the coupl~d pipes when one of the pipes is moved to a new different level or plane. The ball-and-socket-type pipe couplings as disclosed in U.S. Patent No. 2,918,313 and U.S. Patent No.

2,381,426 are capable of the aforementioned automatic establishment of a new cellterline parallel relationsllip thercbetween in response to a variation of the plane where one of a pair of pipcs is disposed, because they are designed so as to permit relative movement in all directions between the pair of conpled pLpcs.
Ilowever, the device of the f;rst-mentioned U.S. patent has a specific construction in which a first half section of a socket housing mollllted on a first pipe and a second half section thereof mounted on a second pipe are screwed together when assembled. An axially and angularly movable joint pipe is not employed between the first and the second half sections of the socket housing, resulting in the fact that freedom of the axial and angular movement is so restricted that it is quite limited in utility and not applicable to piping in such a place where a considerable difference between the pipe-lying levels may occur.
In the device of the second-mentioned U.S. patent, a pair of joint pipes each having a spherical bulge formed integral with its one end are disposed between a pair of socket housings, the pair of joint pipes being different in diameter so as to be relatively telescopical with each other. In other words, in the device of this U.S. patent, two kinds of non-interchangeable joint pipes which are specific in construction and different in diameter are necessary, resulting in an increase of manufacturing cost and inconvenience in application. Further, in this device of the U.S. patent, no positive stopper means are provided for restricting the angular movement of the joint pipes and the relative telescopical motion between the joint pipes, appearing to invite easy breakage and less safety in the coupling.
An object of one aspect of this invention is to provide an improved ball-and-socket-type pipe coupling which is capable of automatic-ally establishing a new parallel relationship between two centerlines of a pair of interconnected pipe lines without losing interconnection therebetween when one of the pair of pipe lines is moved to a new plane or level different from the level of the remainder of the pair of pipe lines.
An object of a further aspect of the present invention is to provide an improved ball-and-socket-type pipe coupling which has a single pi.ece of joint pipe for interconnecting a pair of spaced socket housings each having an internal spherical concave surface, and a pair of cooperat-ing ball members at least one of which is in the form of an annular member having a spherical outer surface disposed in spherically sliding contact with the associated spherical concave surface of the socket housing and relatively slidably mounted on one end section of the joint pipe.
According to a broad aspect of the present invention, a ball-and-socket-type pipe coupling is provided for interconnecting a first pipe ,:
with a second pipe, comprising: a first socket housing fixedly mounted to an end of the first pipe; a second socket housing fixedly mounted to an end of the second pipe; each of the first and second socket housings hav-ing a spherical concave surface formed internally thereof; a single piece of joint pipe of simple cylindrical construction having opposite free end sections; one of the free end sections extending into the first socket housing and the other of the free end sections extending into the second socket housing; a first ball member including an annular member mounted on the one of the free end sections and having a spherical outer surface dis-posed in spherically sliding contact with the concave surface of the first socket housing; a second ball member including an annular member mounted on the other of the free end sections and having a spherical outer surface disposed in spherically sliding contact with the concave surface of the second socket housing; the joint pipe being angularly movable in accord-ance with spherical sliding movement of the first and second ball members with respect to the housing, while maintaining parallel relationship be-tween the first and second pipes; each of the first and second ball mem-bers including a front end section including an annular projection extend-ing radially inwardly and having a first internal annular wall, a rear end section which is formed with an annular extension extending radially inwardly and having a second internal annular wall, and an annular hollow Space extending between the first and second internal annular walls; a first stop member fixedly mounted on one of the free end sections of the joint pipe and disposed within the annular hollow space of the first ball member, preferably in its center; a second stop member fixedly mounted on the the other of the free end sections of the joint pipe and disposed within the annular hollow space of the second ball mem-ber, preferably in its center; the joint pipe thus being telescopically slidable in its axial directions with respect to the first and second ball members within a limited range.
By a variant of the invention, each of the first and second socket housings has a stopper surface formed at its free end for re-stricting an excessive angular movement of the joint pipe.
By a further variant, each of the socket housings are comprised of a first half section and a second half section coupled together.
By still another variant, the projection is formed of a separ-dte piece of metal and embedded in the front end section of the annular member, preferably by screwing.

~, ~ 1562~6 By still another variant, at least one sealing member is inter-posed between the socket housing and the ball member.
By another variant, at least one sealing member is interposed between the joint pipe and the annular member.
By still another variant, at least one indication means is provided in position on a periphery of the joint pipe for giving a visible warning against an excessive axial movement of the joint pipe with rela-tive to the annular member.
By a variation thereof, the indication means is a colored zone.
Thus, the present invention in its various aspects, provides a pipe coupling which is particularly advantageous when utilized in areas where it is necessary to connect a pair of parallel pipe lines lying on two different planes or it is expected that a pair of connected pipe lines might be subjected to dislocation by an earthquake, subsidence of ground, or considerable weight, shocks or vibrations. The pipe coupling according to aspects of this invention is also very useful in repairing such pipe lines that have been misaligned or actually affected by dis-location or subsidence of ground.

- 4 a -~3 11 115628~

¦~ In the accompanyiny drawings:
Figure 1 is a side el.evation with parts broken away, showing one embodirnent of the ball_and-socket-type pipe coupling .le~(lr~ to an as~ect of thc presf.nt invelltion;
F.igure 2 is an enlargcd vicw showiny a part of Figure l;
Figure 3 is a side eleva~ion wi.th parLs broken away, sh~wing a cen~erline offset positi.on of ~-he coupl.ed pipes of Figure 1;
Figure 4 is a similar view to Figure 3, but showing a centerline offset and axially extended position of the coupled pipes of Figure l;
Figure 5 is a similar view to Fiyure 1, showing the modification of the couplin~ of an aspect of this invention;
Fiyure 6 is a side elevation with parts brokcn away, g~ ~wing another eml~odiment of the coup]ing of nnother agpect of tlle present invention;
Figure 7 is a side elevation with parts broken away, showing a centerline offset position of the coupled pipes of Figure 6; and Figure 8 is a similar view to Figure 7, but showing a centerline offset and axially extended position of the coupled pipes of Figure 6.
The ball and socket type pipe coupling of an aspect of this invelltion comprises a pair of axially spaced socket housings la, lb each of which is preferably a cup or bell-shaped member having open ends and internally formed with a spherical concave surface 2.

1~ 1156286 Tn the first embodjment as illustrated in Yigures 1 to 4, one end of the first housing la may be formed with a flange 3_ for connection with a f~rst pipe line 4_ by means of a cooperating flange 5_ formed at the opposcd end of the pipe line 4a, while the sacond housing ]b may also be formed with a flangc 3b for con-necti.on with a second pipe ].ine 4_ by means of a cooperating flange 5b forrned at ~he opposed end of the pipe l;.ne 4b. Ilowever, in c.lse where a di.ameter of the employed pipes or a maximum fluid pressure to be applied to thé pipe lines are so limited that safety is we11 maintained, the connection between the first pipe line 4_ and the first housing 1_ as well as the connection between the second pipe line 4b and the second housing 1_ may be achieved by screwing as indicated at 3 in Figure 5.
The socket housings 1_, lb may be a single piece structure;
however, for the convenience of easy manufacture and disassembly, each of the housings la, l_ may preferably be comprised of two separate pieces, that is, a first half section 6 and a second half section 7 which are coupled together when in use, for example by means of bolts 8 and nuts 9 as illustrated in Figures 1 to 4 or by screwing as indicated at 8' in Figure 5. In maintenance, by removing the bolts 8 or by unscrewing at 8', the first half section 6 of the housing can be easily removed for inspection or replacement of the sealing members 22, 23, 25 and/or the stop ring 15. A free end 10 of each of the first half sections 6 is ..
formed with a surface 10' serving as a stopper for the purpose to be hereinafter described. soth of the housings 1_, lb may be structurally symmetrical, but more preferably, be structurally identical for interchangeability.
In the embodiments shown in Figures 1 and 5, a single piece of joint pipe 11 is telescopically interposed between the 1 15~286 pair of axially spaced housings la, lb with each of its opposite end sections 11' extending into the housings, respectively. The meaning of the term "a single piece of ~oint pipe" herein used should not be limited so strictly but includes in its scope a pair of pipes made separately and then connected together hy welding, screwing, or the like conventional method.
Ball ~embers in the form of annular members 12a, 12b, each having a spherical outer surface 13, are respectively unted on the o~osite end sections 11' of the joint pipe 11. m e spherical radius of the surfaces 13, 2 are in spherically sliding contact with each other.
Thus, the ball members are independently rockable or angularly movable with respect to the associated housings. Each of the annular members 12a, 12b is internally formed with an annular hollow space 14 extending between its front and rear end sections. Within the hollow space 14, a stop mem-ber 15, preferably a split stop ring, is disposed and fixedly mounted on each of the end sections 11' of the joint pipe 11. The stop rings 15 should be prevented from axial dislocation. For this purpose, as best shown in Figure 2, it is preferable to form an annular groove 16 in the periphery of each of the end sections 11l of the pipe 11 so that the stop -ring 15 can be snap fit thereinto. Further, each stop ring 15 preferably is respectivély located substantially in the center of the distance (L2) (Figure 3) of the space 14 when the joint pipe 11 is in its normal posi-tion as shown in Figures 1 and 2.
The front end section 17 of each of the annular members 12a, 12b is formed with an annular projection 18 serving as a stopper and also as a guide for the relative axial movement between the joint pipe 11 and the associated annular member. m e projection extends radially inwardly and E~

has an internal wall 18' (Figures 2 and 5) arranged so as to be engageable with the stop ring 15. For convenience of assembly and disassembly, this projection 18 may preferably be formed of a separate piece of metal and then be embedded in the front section 17, as best shown in Figure 2.
Alternatively, the projection may be mounted to the front end of each annular member by screwing as indicated at 24 in Figure S. It is also possible to form the projection 18 so as to be integral with each body of the annular members 12a, 12b. The configuration of the projection may be modified in various ways. The length (Ll~ (Figure 3) of the joint pipe 11 should be predetermined in the manner as will be hereinafter described.
The rear end section of each of the annular members 12a, 12b is formed with an annular extension 19 which extends radially inwardly and has an internal wall 19' (Figure 2). The extension 19 is formed with a pair of annular grooves 20, 21 in which a pair of known sealing members 22, 23 such as sealing rings or packings are fixedly positioned, so that a desired fluid sealing effect can be obtained between the joint pipe 11 and the annular members. One pair of sealing members 22, 23 may be eliminated as shown at ~2' in Figure 5, or three or more sealing members (not shown) may be employed, if desired. It is important that the seal-ing member or members should be arranged so as to permit axially sliding motion of the joint pipe 11 relative to the annular members 12a, 12b.
A further sealing member 25 e.g., a sealing ring or packing known per se is interposed between the first housing la and the annular member 12a, and also between the second housing lb and the annular member 12_ for the known fluid sealing effect.
As shown in Figures 2 and 4, the joint pipe 11 may preferably y 1 ~5628~

be provided with a pair of indication zones 26 on the periphery thereof in order that an operator or plumber can easily - 8 a ~

~¦re~co~ni~c how far t}le joint plpe 6~ is axially 1JUI1ed out of the ~ ousi.ngs. If the jo.int pipe has been pulled out to the maximum deyree, the operator can know the fact by the indication zones 26 and do something to prevent an accident or damage to the coupling which might be caused for instance by an excessive fluid pressure axially appli.ed to the coupling. The indication means may be a pa.i.nted zone, a colored tape, scale mark.s or any other. suitable ones known per se.
In the embodiment of ~igure 2, the indication zones 26 are respectively located under the annular projection 18, and the width (W) of the indication zone is substanti.ally equal to one half of the distance (Dl) between the projection 18 and the stop ring 15. Thus, when the joint pipe ll is positioned at its non-pulled out position as shown in Figures 1 and 3, the indication zones 26 are not visible from outside. However, as the pipe ll is pulled out of the housings la, lb, the indication zones come to appear gradually. When the pipe ll is pulled out of the housings to the maximum degree, in oth~r words, the pipe coupling takes its maximum extended position as shown in Figure 4, the indication zones appear substantially entirely to give a visible warning information that the pipe 11 should not be pulled out any more.
Figures 6 to 8 illustrate another embodiment of tl~e coupling of an aspect of this invention, wherein one of the ball members is in the form of a spherical bulge 12_ formed integral with or connected to one end of the joint pipe ll. The bulge 12_ has a spherical outer surface 13' whose spherical radius is equal to that of the internal spherical surface 2 of the housing l_ for achieving a relatively sllding contact relationship therebetween. Thus, the joint pipe ll is angularly movable with respect to the housing la. As will be noted from Figures 6 to 8, the fundamental structure of the _g_` -1 156~86 modification other than the ball member 12c is substantially the same with the structure of the preceding embodiment already described wi.th reference to Figures 1 to 4~
The pipe coupling according to aspects of this invention is normally installed in such a manner that the centerline Cl of the first pipe line 4a and the centerline C2 of the second pipe line 4_ lie on the same plane or level, as shown in Figures 1, 5 and 6. When the level where the second pipe line 4_ lies is lowered in the direction of an arrow P
(figures 3 and 7~, for instance, by ground subsiding, resulting in that the centerline C2 of the second line 4b is forcibly lowered by the dis-tance (Hl) with respect to the centerline C2 of the first line 4a, while maintaining the parallel relationship therebetween, the joint pipe 11 can be inclined in the direction of an arrow Q (Figures 3 and 7) by a cer-tain angle e defined by the (Hl) since both of the ball members are inde-pendently rockable with respect to the socket housings. If the joint pipe is inclined to the maximum degree, the stopper surfaces 10~ of the hous-in~s come into contact with the periphery of the pipe 11 to restrict a further inclination thereof, as shown in Figures 3, 4, 7 and 8. However, if the level where the second pipe line 4b lies is lowered by more than the distance (Hl) and if the housing l_ and the line 4b are permitted to go down further in the direction of an arrow R (Figures 4 and 8) by their own weight, while maintaining the parallel relationship between the centerlines Cl and C2, the ball member 12b axially slides down on the joint pipe 11 until the internal wall 18' of the annular projection 18 is engaged with the stop ring 15. In this case, as will be easily under-stood, the value of the angle ~ does not vary but the distance (H2~ be-tween the centerlines Cl and C2 is increased as compared to the afore-1 1~6286 mentioned distance (Hl). It be also easily understood that the value of (H2) in Figure 4 is greater than that in Figure 8, because, in the embodiment of Figures 1 to 4, the pipe 11 is axially slidable within sub-stantially the range of the distance (L2) (Figures 2 and 3), with relative to the ball member 12a in the direction of an arrow R, while, in the em-bodiment of Figures 6 to 8, the pipe 11 is not axially slidable relative to the lefthand ball member 12c.
When a sudden fluid pressure is axially imparted to the coupled pipe lines lying on the same plane, one or both of the socket housings la, lb can slide axially within substantially the range of the distance (L2), with the result that the fluid pressure is advantageously absorbed to prevent a possible accident. If the joint pipe ll-is fully pulled out of the socket housing, the indication zone 26 appears to give a visible warn-ing as described hereinabove.
The pipe coupling according to aspects of this invention is also very useful in connecting a pair of parallel pipe lines which lie on dif-ferent planes or levels. For instance, when the pair of pipe lines are extending in parallel with each other with a certain distance ~Hl) there-between, an inclination angle e and the length (Ll) or (L2) of the joint pipe can be adjusted so as to properly meet the distance (Hl). If a dis-tance (D2) (Figure 3) between the pair of housings is so narrow, a joint pipe shorter than a standard length should be employed. On the other hand, if the distance (D2) is too~large to be absorbed by adjustment of the inclination angle O of a standard joint pipe 11, a joint pipe longer than the standard length should be employed. In this way, by preparing a longer or shorter joint pipe, it is possible to absorb the distance (D2) whatever value it may be, Further, by varying a distance (L2) of the hollow space 14 and/
or a distance lL3) between a pair of stop rings 15, it is possible to adjust the sliding area of the joint pipe. It is also :: ' :

:~'~' :, ; :

~ 11 a -~ B

~1 1156;~
p~ssibic to udjus~ the ia~cli.na~i~n an~31e ~ by varying a L~osition ~f the sto~per surface 10'.
Since it is very easy to adjust a lcnc3th (Ll) or (Ll') of a joint pipe or a distance (L3) between a pair of stop rings beforehand or even at an actual job site, the pipe coupling of aspccts of tlli.s invention has a large adjllstability to absorb any '.
cl1.starlcc (Ill) between two cent:erlLIles Cl, C2 of a pair of pipe lines 4a, ~b wi~:hout losi.llg a para].lel rela~iollship tl~ere~e~ween and thus has a wide utility and convenience in actual applica-tion. In particu-lar with the embodiments of Figures 1 and 5, if a straight material pipe (not bulged at one end) of a sufficient length and a known slotting and cutting tool (or a slotter and a pipe cutter) are avai~able at the actual job site, the required repair to the damaged interconnection between the two pipe lines can be easily performed whatever distance (D2) (Figure 3) between a pair of housings la, l may be. Also with the embodiment of Figure 6~
the afore-mentioned repair can be easily performed conditioned of either such a material pipe a~ having a spherical bulge 12c formed at its one end and a sufficient length (Ll') (Figure 7) in its straight section or a combination of a ball member 12a and a sufficient length (Ll) of straight meterial pipe without a spherical bulge 12c is available at the actual job site. This particular advantage cannot be expected from the known pipe jco~pli devices heretofore proposed.

Claims

THE EBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A ball and socket type pipe coupling for interconnecting a first pipe with a second pipe, comprising:
a first socket housing fixedly mounted to an end of said first pipe;
a second socket housing fixedly mounted to an end of said second pipe;
each of said first and second socket housings having a spherical concave surface formed internally thereof;
a single piece of joint pipe of simple cylindrical con-struction having opposite free end sections;
one of said free end sections extending into said first socket housing and the other of said free end sections extending into said second socket housing;
a first ball member including an annular member mounted on said one of said free end sections and having a spherical outer sur-face disposed in spherically sliding contact with said concave surface of said first socket housing;
a second ball member including an annular member mounted on the other of said free end sections and having a spherical outer sur-face disposed in spherically sliding contact with said concave surface of said second socket housing;
said joint pipe being angularly movable in accordance with spherical sliding movement of said first and second ball members with respect to said housing, while maintaining parallel relationship between said first and second pipes;

each of said first and second ball members including a front end section including an annular projection extending radially inwardly and having a first internal annular wall, a rear end section which is formed with an annular extension extending radially inwardly and having a second internal annular wall, and an annular hollow space extending between said first and second internal annular walls;
a first stop member fixedly mounted on said one of said free end sections of said joint pipe and disposed within said annular hollow space of said first ball member;
a second stop member fixedly mounted on said other of said free end sections of said joint pipe and disposed within said annular hollow space of said second ball member;
and said joint pipe being telescopically slidable in its axial directions with respect to said first and second ball members within a limited range.

2. The pipe coupling as claimed in Claim 1, wherein each of said first and second socket housings has a stopper surface formed at its free end for restricting an excessive angular movement of said joint pipe.

3. The pipe coupling as claimed in Claim 1, wherein each of said socket housings are comprised of a first half section and a second half section coupled together.

4. The pipe coupling as claimed in Claim 1, wherein said pro-jection is formed of a separate piece of metal and embedded in said front end section of the annular member.

5. The pipe coupling as claimed in Claim 1, wherein said pro-jection is formed of a separate piece of metal and mounted to said front end section of the annular member by screwing.

6. The pipe coupling as claimed in Claim 1, wherein at least one sealing member is interposed between said socket housing and said ball member.

7. The pipe coupling as claimed in Claim 1, wherein at least one sealing member is interposed between said joint pipe and said annular member.

8. The pipe coupling as claimed in Claim 1, wherein at least one indication means is provided in position on a periphery of said joint pipe for giving a visible warning against an excessive axial movement of the joint pipe with relative to said annular member.

9. The pipe coupling as claimed is Claim 7, wherein said indication means is a colored zone.

10. The pipe coupling of Claim 1, wherein said first stop member is disposed within the center of said annular hollow space of said first ball member.

11. The pipe coupling of Claim 1, wherein said second stop member is disposed within the center of said annular hollow space of said second ball member.

12. The pipe coupling of Claim 10, wherein said second stop member is disposed within the center of said annular hollow space of said second ball member.