Pipe coupling

• US 5,280,969 A
• Filed: 06/17/1991
• Issued: 01/25/1994
• Est. Priority Date: 06/18/1990
• Status: Expired due to Fees

• Current Assignee: Straub Federnfabrik AG
• Original Assignee: Straub Federnfabrik AG
• Inventors: Straub, Immanuel
• Primary Examiner(s): Reese, Randolph A.
• Assistant Examiner(s): SHACKELFORD, HEATHER CHUN
• Application Number:
  US07/716,139
• Time in Patent Office: 953 Days
• Field of Search: 285/373, 285/112, 285/104, 285/105, 285/108, 285/383
• US Class Current: 285/105
• CPC Class Codes: F16L 17/04 with longitudinally split or divided sleeve

Abstract

A pipe coupling having an elastomer sealing sleeve which is approximately C-shaped in cross-section has a cylindrical housing which is split in the longitudinal direction, and which defines inwardly bent end walls and can be constricted like a pipe clip by means of a closure having tensioning screws, in which arrangement the sleeve, which is enclosed at the end faces and at the circumference by the housing and by a metal insert sheet bridging the housing gap and is approximately C-shaped in cross-section, is compressed in the circumferential direction and is brought to bear against the pipes to be coupled. Sliding rings, which are compressible in the circumferential direction, are located between the end faces of the sleeve and the end walls of the housing. Upon assembly of the coupling, these sliding rings are brought to bear against the outer walls of the pipes and form a sliding seat with the latter. This leads to increased insensitivity to changes with regard to the relative position of the sealing parts and the parts to be sealed, as well as to further increases in the existing adaptability of the coupling to irregular pipes.

Claims

1. In a pipe coupling of the type comprising an elastomer sealing sleeve which is approximately C-shaped in cross-section and defines sealing lips which extend toward each other and are each supported on a sleeve web by means of an annular bead;

a housing comprising a cylindrical jacket which surrounds the sleeve and which defines radial end walls and a longitudinal gap, said housing further comprising an insert sheet which is inserted between the sleeve and the jacket and which bridges the longitudinal gap; and

a closure comprising tensioning bolts operative to constrict the housing;

wherein the sealing lips of the sleeve define first, larger dimensions before the housing is constricted, and wherein it is possible for said sealing lips to be compressed in the circumferential direction and to be pressed snugly onto respective pipe walls due to compression of the annular beads as the housing is constricted;

the improvement comprising;

means for forming a sliding seat between the pipe coupling and the pipe walls after the housing is constricted to permit axial displacement of the pipe walls with respect to the housing, said means comprising a ring inserted on each side between the sealing sleeve and the respective radial end wall of the housing, said ring being compressible in the circumferential direction and defining an inwardly directed sliding surface, wherein said sliding surface defines first, larger dimensions before the housing is constricted, and wherein said sliding surfaces are configured to bear on the pipe to form a sliding seat with the pipe as the housing is compressed.

2. The pipe coupling as claimed in claim 1, wherein the sleeve defines an extension snugly enclosing the ring.

3. The pipe coupling as claimed in claim 2, wherein the extension defines a cross-section tapering to the outside, and wherein the ring forms together with the housing an annular space of corresponding profile.

4. The pipe coupling as claimed in claim 1, wherein the sliding ring is made of a compressible material.

5. The pipe coupling as claimed in claim 4, wherein the ring is made of polyethylene.

6. The pipe coupling as claimed in claim 1, wherein the ring comprises a snap ring that defines two ends separated by a slit, and wherein the slit closes directly before the housing is tightened to a final position.

7. The pipe coupling as claimed in claim 1, wherein the ring comprises a helical spring having coils bearing tightly after compression, and a wire-shaped snap ring which engages in the helical spring.

8. The pipe coupling as claimed in claim 7, wherein the snap ring has larger dimensions in relation to the width of the housing before constriction of the housing.

9. In a pipe coupling of the type comprising an annular elastomer sealing sleeve which is approximately C-shaped in cross-section and defines annular sealing lips which extend toward each other and are each supported on an annular sleeve web by means of an annular bead;

a housing comprising a cylindrical jacket which surrounds the sleeve and which defines radial end walls and a longitudinal gap;

a closure comprising tensioning bolts operative to constrict the housing; and

an insert sheet which is inserted between the sleeve and the housing and bridges the longitudinal gap, wherein the sealing lips of the sleeve define first, larger dimensions before the housing is constricted, and wherein it is possible for said sealing lips to be compressed in the circumferential direction and to be pressed snugly onto a pipe wall due to compression of the annular beads as the housing is constricted;

the improvement comprising;

a ring inserted on each side between the sealing sleeve and the respective radial end wall of the housing, said ring being compressible in the circumferential direction and defining an inwardly directed sliding surface, wherein said sliding surface defines first, larger dimensions before the housing is constricted, and wherein said sliding surfaces are configured to bear on the pipe to form a sliding seat with the pipe as the housing is compressed;

wherein the sleeve defines an extension snugly enclosing the ring.

10. The pipe coupling as claimed in claim 9 wherein the extension defines a cross-section tapering to the outside, and wherein the ring forms together with the housing an annular space of corresponding profile.

11. In a pipe coupling of the type comprising an elastomer sealing sleeve which is approximately C-shaped in cross-section and defines sealing lips which extend toward each other and are each supported on a sleeve web by means of an annular bead;

a housing comprising a cylindrical jacket which surrounds the sleeve and which defines radial end walls and a longitudinal gap;

a closure comprising tensioning bolts operative to constrict the housing; and

an insert sheet which is inserted between the sleeve and the housing and bridges the longitudinal gap, wherein the sealing lips of the sleeve define first, larger dimensions before the housing is constricted, and wherein it is possible for said sealing lips to be compressed in the circumferential direction and to be pressed snugly onto a pipe wall due to compression of the annular beads as the housing is constricted;

the improvement comprising;

a ring inserted on each side between the sealing sleeve and the respective radial end wall of the housing, said ring being compressible in the circumferential direction and defining an inwardly directed sliding surface, wherein said sliding surface define first, larger dimensions before the housing is constricted, and wherein said sliding surfaces can be brought as the housing is compressed to bear on the pipe to form a sliding seat with the pipe;

wherein the ring comprises a snap ring that defines two ends separated by a slit, and wherein the slit closes directly before the housing is tightened to a final position.

12. In a pipe coupling of the type comprising an elastomer sealing sleeve which is approximately C-shaped in cross-section and defines sealing lips which extend toward each other and are each supported on a sleeve web by means of an annular bead;

a housing comprising a cylindrical jacket which surrounds the sleeve and which defines radial end walls and a longitudinal gap;

a closure comprising tensioning bolts operative to constrict the housing; and

an insert sheet which is inserted between the sleeve and the housing and bridges the longitudinal gap, wherein the sealing lips of the sleeve define first, larger dimensions before the housing is constricted, and wherein it is possible for said sealing lips to be compressed in the circumferential direction and to be pressed snugly onto a pipe wall due to compression of the annular beads as the housing is constricted;

the improvement comprising;

a ring inserted on each side between the sealing sleeve and the respective radial end wall of the housing, said ring being compressible in the circumferential direction and defining an inwardly directed sliding surface, wherein said sliding surface defines first, larger dimensions before the housing is constricted, and wherein said sliding surfaces can be brought as the housing is compressed to bear on the pipe to form a sliding seat with the pipe;

wherein the ring comprises a helical spring having coils bearing tightly after compression, and a wire-shaped snap ring which engages in the helical spring;

wherein the snap ring has larger dimensions in relation to the width of the housing before constriction of the housing.

13. A method for coupling two pipes comprising the following steps:

a) providing a pipe coupling of the type comprising an elastomer sealing sleeve which is approximately C-shaped in cross-section and defines sealing lips which extend toward each other and are each supported on a sleeve web by means of an annular bead;

a housing comprising a cylindrical jacket which surrounds the sleeve and which defines radial end walls and a longitudinal gap;

a closure comprising tensioning bolts operative to constrict the housing; and

an insert sheet which is inserted between the sleeve and the housing and bridges the longitudinal gap, wherein the sealing lips of the sleeve define first, larger dimensions before the housing is constricted, and wherein it is possible for said sealing lips to be compressed in the circumferential direction and to be pressed snugly onto a pipe wall due to compression of the annular beads as the housing is constricted;

said pipe coupling further comprising a ring inserted on each side between the sealing sleeve and the respective radial end wall of the housing, said ring being compressible in the circumferential direction and defining an inwardly directed sliding surface, wherein said sliding surface defines first, larger dimensions before the housing is constricted, and wherein said sliding surfaces can be brought as the housing is compressed to bear on the pipe to form a sliding seat with the pipe.

b) positioning the pipe coupling around and over a pair of aligned pipes with each sealing lip aligned with a respective pipe; and

c) tightening the tensioning bolts to constrict the housing, thereby pressing the sealing lips snugly onto the respective pipe walls; and

(d) forming sliding seats between the sliding surfaces and the pipe walls during step (c) by compressing the rings in the circumferential direction to being the sliding surfaces to bear on the respective pipes.