RELEASABLE TUBE COUPLING

• US 3,743,326 A
• Filed: 05/10/1972
• Issued: 07/03/1973
• Est. Priority Date: 05/10/1972
• Status: Expired due to Term

• Current Assignee: Louis B. Courtot, Richard H. Dickinson Jr
• Original Assignee: Louis B. Courtot, Richard H. Dickinson Jr
• Inventors: Courtot, Louis B., Dickinson, Richard H. Jr.
• Primary Examiner(s): Callaghan, Thomas F.
• Application Number:
  US05/252,043
• Time in Patent Office: 419 Days
• Field of Search: 285/113,105,104,102,101,100,257,382.7,323,343,308,322,249
• US Class Current: 285/105
• CPC Class Codes: F16L 33/16 with sealing or securing means using fluid pressure
• CPC Class Codes: F16L 37/0925 with rings which bite into the wall of the pipe
• CPC Class Codes: F16L 37/0927 the wedge element being axially displaceable for releasing the coupling

Abstract

A releasable fluid coupling for connecting a flexible plastic tube to a body member includes a sleeve, a tube gripping collet and an O-ring seal. The collet carries gripping surfaces which engage the outer surfaces of the tube and axial outward movement of the collet causes the collet fingers to grip the tube more tightly because of the engagement of the conical cam surfaces on the sleeve and collet fingers. The collet carries stop means for limiting axial movement of the collet and gripping may take place at two axially separated zones and different conical cam angles impart rotational movement to the ends of the collet fingers to provide different amounts of radial movement for the two axially spaced gripping surfaces.

Claims

1. A releasable fluid coupling for connecting a flexible resilient tube to a body member having a fluid passage therein comprising an enlarged bore in said body member connecting with said fluid passage, a collet member in said bore adapted to receive and grip a tube received therein, said collet having a base portion surrounding said tube and a plurality of resilient fingers each extending axially inwardly from said base portion and terminating at its inner end in a tip portion, said tip portions having on their outer peripheral surface a first conical cam surface, a second conical cam surface on said body member in said bore and engageable by said first conical cam surface upon axial movement of said collet out of said bore to radially constrict said tip portions, said tip portions on their inner periphery defining an annular gripping means having an internal diameter less than the outer diameter of said tube when said finger portions are in the normal undeflected position, whereby said tube is gripped by said gripping means when said first and second conical cam surfaces are out of engagement with each other, and said collet and said tube are movable axially together in said bore, said bore defining an end wall adjacent said fluid passage engageable by the end of said tube, stop means on said collet and said body member to allow limited axial movement of said tube and collet so that axial movement of said tube into said collet causes said collet to move axially inward until said stop means are engaged and the end of said tube engages said end wall and said first and second cam surfaces are out of engagement, and axially outward movement of said collet and said tube is limited by the engagement of said stop means to limit movement of the end of said tube away from said end wall and to limit the radial constriction of said tip portions, and seal means in said bore axially inwardly of said collet in sealing engagement with the outer surface of said tube and said body member.

2. A releasable fluid coupling as set forth in claim 1 wherein said tip portions have on their inner periphery a second annular gripping means axially inward from said first annular gripping means, said second annular gripping means defining an internal diameter greater than the outer diameter of said tube when said finger portions are in the normal undeflected positions, and axially outward movement of said collet causes radially inward movement of said tip portions whereby both of said gripping means engage the tube at axially spaced locations.

3. A releasable fluid coupling as set forth in claim 1 wherein said body member has an arcuately curved concave surface between said enlarged bore and said end wall and engageable by said seal means to provide progressive radial compression of said seal means as said seal means moves toward said end wall and the end of said tube.

4. A releasable fluid coupling as set forth in claim 1 wherein said tip portions on their axially inner end faces define a concave surface adapted to receive said seal means under pressure conditions to limit outward extrusion of said seal means.

5. A releasable fluid coupling set forth in claim 1 wherein said stop means comprises a radially outwardly extending flange on said tip portions and a pair of axially spaced shoulders on said body member, one shoulder on each side of said flange.

6. A releasable fluid coupling as set forth in claim 1 wherein said stop means to limit outward movement of said collet comprises a radial flange on said tip portions and a radial shoulder on said body member, anD said stop means to limit inward movement of said collet comprise a radial projection on said collet base portion engageable with said body member radially outward of said enlarged bore.

7. A releasable fluid coupling as set forth in claim 1 wherein said second conical cam surface is on a sleeve secured in said enlarged bore and said collet is slidably carried in said sleeve.

8. A releasable fluid coupling for connecting a flexible resilient tube to a body member having a fluid passage therein comprising an enlarged bore in said body member connecting with said fluid passage, a collet member in said bore adapted to receive and grip a tube received therein, said collet having a base portion surrounding said tube and a plurality of resilient fingers each extending axially inwardly from said base portion and terminating at its inner end in a tip portion, said tip portions having on their outer peripheral surface a first conical cam surface, a second conical cam surface on said body member in said bore and engageable by said first conical cam surface upon axial movement of said collet out of said bore to radially constrict said tip portions, said tip portions on their inner periphery defining at least two axially spaced annular gripping means, one of said gripping means having an internal diameter less than the outer diameter of said tube when said finger portions are in the normal undeflected position, whereby said tube is gripped by said one gripping means when said first and second conical cam surfaces are out of engagement with each other, and said collet and said tube are movable axially together in said bore, the other of said gripping means being axially inward of said one gripping means and having an internal diameter greater than the outer diameter of said tube when said finger portions are in the normal undeflected position, said other gripping means being engageable with the outer surface of said tube when said tip portions are radially constricted, and seal means in said bore axially inwardly of said collet in sealing engagement with the outer surface of said tube and said body member.

9. A releasable fluid coupling as set forth in claim 8 wherein the conical angle of said first conical cam surface is greater than the conical angle of said second conical cam surface and axially outward movement of said collet produces a rotational movement of said tip portions to bring said first and second conical cam surfaces into surface abutting contact, whereby said other gripping means moves a greater radial distance than said one gripping means.

10. A releasable fluid coupling as set forth in claim 8, including stop means on said collet and said body member to limit axially inward movement of said collet toward said seal means.

11. A releasable fluid coupling as set forth in claim 10, including a second stop means on said collet on said body member to limit axially outward movement of said collet away from said seal means.

12. A releasable fluid coupling as set forth in claim 11 wherein said tip portions include a sloping outer peripheral surface adjacent said other gripping means and engageable by said seal means so that under high pressure conditions engagement of said seal means with said sloping surface increases the radially inward force of said other gripping means against said tube.