Tube coupling for smooth walled tubes

Claim 2

A tube coupling comprising a barrel having a bore at one end, an uninterrupted smooth walled right-circular cylindrical tube received in said bore, a generally right-circular cylindrical grip pin, said barrel having a bore for reception of said grip pin intersecting said tube receiving bore whereby said pin when mounted in said grip pin receiving bore is spaced from said diametrically opposed tube receiving bore wall less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive, said grip pin being mounted in said grip pin receiving bore for rotation about its longitudinal axis, said grip pin when mounted in the grip pin receiving bore with a first angular position about its axis having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on said grip pin associated with said bore clearing region of said pin with said grip element engaging with said smooth walled right-circular cylindrical tube inserted in said tube receiving bore, means in said barrel for resiliently biasing a tube inserted in said tube receiving bore toward said one end, said grip element engaging a smooth wall portion of said smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said element is over center of said grip pin longitudinal axis toward said biasing means whereby said biasing means tends to increase the gripping force on a tube in said tube receiving bore while displacing said tube toward said one end.

Claim 3

A tube coupling according to claim 1 wherein said grip element is in the intersection of said bore clearing region with the right-circular cylindrical surface of said pin.

Claim 4

A tube coupling according to claim 1 including means secured to said grip pin for rotating said pin between the tube receiving bore clearing position and the tube engaging position.

Claim 5

A tube coupling according to claim 3 including biasing Means tending to rotate said grip pin toward said tube gripping position.

Claim 6

A tube coupling comprising a barrel having a first bore at one end for the reception of a smooth walled right-circular cylindrical tube and having a second bore of greater diameter than said tube receiving bore extending from a second end opposite said one end to said tube receiving bore and coaxial with said tube receiving bore, a generally right-circular cylindrical grip pin, said barrel having a bore for reception of said grip pin intersecting said tube receiving bore whereby said pin when mounted in said grip pin receiving bore is spaced from said diametrically opposed tube receiving bore wall less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive, said grip pin being mounted in said grip pin receiving bore for rotation about its longitudinal axis, said grip pin when mounted in the grip pin receiving bore with a first angular positon about its axis having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on said grip pin associated with said bore clearing region of said pin adapted for engagement with a smooth walled right-circular cylindrical tube inserted in said tube receiving bore, a resilient seal cylindrical in said second bore, a seal backup element abutting the end of said seal cylinder proximate said second end of said barrel, and means to releasably secure said backup element to said barrel, said seal cylinder resiliently biasing a tube inserted in said tube receiving bore toward said one end, said grip element being adapted to engage a smooth walled portion of a smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said element is over center of said grip pin longitudinal axis toward said second end whereby the biasing force of said seal cylinder acting on a tube in said tube receiving bore tends to increase the gripping force on said tube while displacing said tube toward said one end.

Claim 7

A tube coupling comprising a barrel having a first bore at one end for the reception of a smooth walled right-circular cylindrical tube and having a second bore of greater diameter than said tube receiving bore extending from a second end opposite said one end to said tube receiving bore and coaxial with said tube receiving bore, a generally right-circular cylindrical grip pin, said barrel having a bore for reception of said grip pin intersecting said tube receiving bore whereby said pin when mounted in said grip pin receiving bore is spaced from said diametrically opposed tube receiving bore wall less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive, said grip pin being mounted in said grip pin receiving bore for rotation about its longitudinal axis, said grip pin when mounted in the grip pin receiving bore with a first angular positon about its axis having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on said grip pin associated with said bore clearing region of said pin adapted for engagement with a smooth walled right-circular cylindrical tube inserted in said tube receiving bore, a resilient seal cylindrical in said second bore, a seal backup element abutting the end of said seal cylinder proximate said second end of said barrel, and means to releasably secure said backup element to said barrel, said seal cylinder resiliently biasing a tube inserted in said tube receiving bore toward said one end, said grip element being adapted to engage a smooth walled portion of a smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said element is over center of said grip pin longitudinal axis toward said second end whereby the biasing force of said seal cylinder acting on a tube in said tube receiving bore tends to increase the gripping force on said tube while displacing said tube toward said one end.

Claim 8

A tube coupling according to claim 5 wherein said seal cylinder has a coaxial passage and said backup element has a passage therethrough in registry with said coaxial passage.

Claim 9

A tube coupling according to claim 6 including a seal bead protruding from said cylinder abutting surface of said backup element and extending around the entrance to said passage in said backup element to close upon itself to engage the end of said seal cylinder over a closed path.

Claim 10

A tube coupling according to claim 5 wherein said seal backup element is rotatable around the longitudinal axis of said tube receiving bore while secured in abutting relationship to said seal cylinder.

Claim 11

A tube coupling according to claim 7 wherein said seal bead is circular and concentric with the longitudinal axis of said tube receiving bore and wherein said seal element is rotatable around the longitudinal axis of said tube receiving bore while secured in abutting relationship to said seal cylinder.

Claim 12

A tube coupling according to claim 5 wherein said backup element is a stub cylinder extending into said second bore, a locking pin for said backup element, said barrel having a locking pin receiving bore intersecting said second bore whereby said pin when mounted in said bore extends across a cross-sectional chord of said second bore in the region containing said stub cylinder, said stub cylinder having a groove registering with said locking pin for reception of said pin.

Claim 13

A tube coupling according to claim 10 wherein said groove in said stub cylinder extends around the circumference thereof normal to the longitudinal axis thereof whereby said stub cylinder is rotatable with respect to said barrel while engaged by said locking pin.

Claim 14

A tube coupling according to claim 11 wherein said locking pin is rotatable about its longitudinal axis and has a relieved region which is clear of said second bore when rotated to an unlocked position.

Claim 15

A tube coupling comprising a barreL having a first bore at one end, an uninterrupted smooth walled right-circular cylindrical tube received in said first bore, a generally right-circular cylindrical grip pin having a given diameter, said barrel having a tube receiving end at said one end which defines the limit of all elements of said coupling along the longitudinal axis of said bore toward said one end, said barrel having a bore for reception of said grip pin intersecting said tube receiving bore whereby said pin when mounted in said grip pin receiving bore is spaced from said diametrically opposed tube receiving bore wall less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive and the axis of said grip pin is a plane normal to said tube receiving bore spaced from said tube receiving end of said barrel less than said given diameter, said grip pin being mounted in said grip pin receiving bore for rotation about its longitudinal axis, said grip pin when mounted in the grip pin receiving bore with a first angular position about its axis having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on said grip pin adjacent said bore clearing region of said pin engaging with said smooth walled right-circular cylindrical tube inserted in said tube receiving bore, said grip element engaging a smooth wall portion of said smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said element is over center of said grip pin longitudinal axis toward the end of said tube receiving bore opposite said one end, whereby forces tending to bias a tube inserted in said tube receiving bore toward said one end tend to increase the gripping force on said tube.

Claim 16

A tube coupling comprising a barreL having a first bore at one end, an uninterrupted smooth walled right-circular cylindrical tube received in said first bore, a generally right-circular cylindrical grip pin having a given diameter, said barrel having a tube receiving end at said one end which defines the limit of all elements of said coupling along the longitudinal axis of said bore toward said one end, said barrel having a bore for reception of said grip pin intersecting said tube receiving bore whereby said pin when mounted in said grip pin receiving bore is spaced from said diametrically opposed tube receiving bore wall less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive and the axis of said grip pin is a plane normal to said tube receiving bore spaced from said tube receiving end of said barrel less than said given diameter, said grip pin being mounted in said grip pin receiving bore for rotation about its longitudinal axis, said grip pin when mounted in the grip pin receiving bore with a first angular position about its axis having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on said grip pin adjacent said bore clearing region of said pin engaging with said smooth walled right-circular cylindrical tube inserted in said tube receiving bore, said grip element engaging a smooth wall portion of said smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said element is over center of said grip pin longitudinal axis toward the end of said tube receiving bore opposite said one end, whereby forces tending to bias a tube inserted in said tube receiving bore toward said one end tend to increase the gripping force on said tube.

Claim 17

A tube coupling comprising a barrel having a bore at one end for the reception of a smooth walled right-circular cylindrical tube, first and second generally right-circular cylindrical grip pins, said barrel having first and second bores for reception of said first and second grip pins each intersecting said tube receiving bore whereby said pins when mounted in said respective grip pin receiving bores are spaced from said diametrically opposed tube receiving bore wall portions less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive, said first and second grip pins being mounted in said first and second grip pin receiving bores respectively for rotation about their longitudinal axes, said grip pins when mounted in their respective grip pin receiving bores with a first angular position about their axes having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on each of said grip pins associated with their respective bore clearing regions of said pins and adapted for engagement with a smooth walled right-circular cylindrical tube inserted in said tube receiving bore, said grip elements each being adapted to engage a smooth walled portion of a smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said grip elements are over center of their respective grip pin longitudinal axis toward the end of said tube receiving bore opposite said one end, whereby forces tending to bias a tube inserted in said tube receiving bore toward said one end tend to increase the gripping force of each grip element on said tube.

Claim 18

A tube coupling comprising a barrel having a bore at one end for the reception of a smooth walled right-circular cylindrical tube, first and second generally right-circular cylindrical grip pins, said barrel having first and second bores for reception of said first and second grip pins each intersecting said tube receiving bore whereby said pins when mounted in said respective grip pin receiving bores are spaced from said diametrically opposed tube receiving bore wall portions less than the diameter of the smooth walled right-circular cylindrical tube which said bore is adapted to receive, said first and second grip pins being mounted in said first and second grip pin receiving bores respectively for rotation about their longitudinal axes, said grip pins when mounted in their respective grip pin receiving bores with a first angular position about their axes having a region in registry with said tube receiving bore which clears said tube receiving bore, a grip element on each of said grip pins associated with their respective bore clearing regions of said pins and adapted for engagement with a smooth walled right-circular cylindrical tube inserted in said tube receiving bore, said grip elements each being adapted to engage a smooth walled portion of a smooth walled right-circular cylindrical tube inserted in said tube receiving bore when said grip elements are over center of their respective grip pin longitudinal axis toward the end of said tube receiving bore opposite said one end, whereby forces tending to bias a tube inserted in said tube receiving bore toward said one end tend to increase the gripping force of each grip element on said tube.

Claim 19

A tube coupling according to claim 14 including means secured to each of said first and second grip pins for rotating each of said pins between the tube receiving bore clearing position and the tube engaging position.

Claim 20

A tube coupling according to claim 15 including means to couple rotationally the rotating means for one pin with the rotating means for the other pin whereby said pins are rotated in unison.

Claim 21

A tube coupling according to claim 1 wherein said tube receiving bore clearing region of said grip pin has at least two intersecting facets on said pin to form at their intersection a croWn region extending longitudinally of said grip pin, and wherein said grip element is defined by the crown region.

Claim 22

A tube coupling according to claim 17 wherein said crown region when exposed in said tube receiving bore has a central portion spaced from the tube in said bore whereby said crown region engages the tube at spaced locations.

Claim 23

A tube coupling according to claim 5 wherein said means to releasably secure said backup element to said barrel includes a cylindrical member closely fitting within said second bore, a groove in said cylindrical member, a lock pin for said second member, said barrel having a lock pin receiving bore intersecting said second bore and said groove in said cylindrical member when mounted in said second bore whereby said lock pin engages the walls of said groove to retain said cylindrical member in said bore.

Claim 24

A tube coupling according to claim 19 wherein said groove extends circumferentially of said cylindrical member, said lock pin is rotatable in said lock pin receiving bore, said lock pin is cut away to clear said second bore when in one rotational position, and including detenting means for maintaining the rotational position of said lock pin in the positions to extend into and clear said second bore.