초록 ▼

A tube coupling includes a coupling body having a throughway open at one end to receive an end portion of a tube, an annular step in the throughway facing the open end to provide an end stop for a tube end, and an end cap engaging the coupling body for axial movement between forward and retracted po

A tube coupling includes a coupling body having a throughway open at one end to receive an end portion of a tube, an annular step in the throughway facing the open end to provide an end stop for a tube end, and an end cap engaging the coupling body for axial movement between forward and retracted positions on the body. The end cap has an opening for the end portion of the tube to extend therethrough and a tube locking collet in the cap to permit entry of a tube into the cap and to resist withdrawal. An annular seal is located in the coupling body adjacent the annular step, the seal having an inner annular portion with which the tube end is engageable and an outer annular portion, and a sleeve between the locking device and seal to compress the outer annular portion of the seal axially.

대표청구항 ▼

1. A tube coupling to receive and hold a tube comprises:a coupling body having a throughway open at a first end to receive an end portion of a tube, the end portion of the tube terminating at an end face; an annular step in the throughway facing the first end to provide an end stop for the tube; an

1. A tube coupling to receive and hold a tube comprises:a coupling body having a throughway open at a first end to receive an end portion of a tube, the end portion of the tube terminating at an end face; an annular step in the throughway facing the first end to provide an end stop for the tube; an end cap engaging the coupling body for axial movement between forward and retracted positions on the coupling body, the end cap having an opening for the end portion of the tube to extend therethrough and a tube locking device in the end cap to permit entry of the tube into the end cap and to resist withdrawal of the tube; an annular seal located in the coupling body adjacent the annular step, the seal having an axially facing inner annular portion with which the tube end is engageable and an axially facing outer annular portion; and a sleeve acting between the tube locking device and the outer annular portion of the seal for compressing the outer annular portion of the seal axially in response to forward movement of the locking device by the end cap to cause the inner portion of the seal to be pressed into sealing engagement with the end face of the tube. 2. A tube coupling as claimed in claim 1, wherein the annular seal is in the form of an annular disc having the axially facing inner annular portion for engagement by the end face of the tube, and the outer annular portion for engagement by the sleeve.3. A tube coupling as claimed in claim 1, wherein the outer annular portion of the annular seal has an annular projection facing the end of the coupling body with which the sleeve for compressing is engageable, the end portion of the tube engaging the inner annular portion of the seal within the projection so that compression of the projection presses the projection into sealing engagement with an outer surface of the tube.4. A tube coupling as claimed in claim 3, wherein the projection on the outer annular portion of the seal comprises a shallow collar formed on the outer periphery of the seal within which the end portion of the tube may engage, the collar having a rounded end portion with which the sleeve for compressing the outer annular portion of the seal engages.5. A tube coupling as claimed in claim 3, wherein the outer annular portion of the seal has a toroidal shaped projection within which the end portion of the tube engages the seal and with which the sleeve for compressing the outer annular portion of the seal engages the toroidal shaped projection, when compressed, the sealing against the outer surface of the end portion of the tube.6. A tube coupling as claimed in 1, wherein the tube locking device in the cap comprises an annular collet having a plurality of resilient arms and the cap has a cam surface which tapers towards the open end of the cap with which the resilient arms of the collet are engageable to be pressed inwardly with movement of the collet towards the open end of the cap to force the arms into gripping engagement with the tube.7. The tube coupling as claimed in claim 6, wherein the ends of the arms of the collet are engageable with the sleeve for compressing the outer annular portion of the seal so that when the cap is moved in a forward direction on the coupling body, the collet moving with the cap forcing the sleeve for compressing to act on the outer portion of the seal to compress the seal into sealing engagement with the end portion of the tube.8. A tube coupling as claimed in 1, further comprising means for interengaging the cap and the coupling body such that rotation of the cap in one direction drives the cap forwardly on the coupling body and in the opposite direction rearwardly on the coupling body.9. A tube coupling as claimed in claim 8, wherein the means for interengaging comprises the coupling body having a spirally wound groove, and the cap having a projection or projections engaging in the groove to cause the cap to move forwardly or rearwardly on the body with rotation of the cap in one or other direction.10. A tube coupling as claimed in claim 9, wherein the spirally wound groove on the coupling body extends approximately halfway round the coupling body and the cap has a projection engaging in the groove so that a half turn of the cap with respect to the coupling body advances or retracts the cap over the total travel of the cap permitted by the groove.11. A tube coupling as claimed in claim 9, further comprising means for retaining the projection in the fully advanced or fully retarded position in the helically wound groove.12. A tube coupling as claimed in claim 10, further comprising means for retaining the projection in the fully advanced or fully retarded position in the helically wound groove.13. A tube coupling to receive and hold a tube, the tube coupling comprising:a coupling body having an interior surface bounding a throughway, the throughway being adapted to receive a first end of a tube, the first end of the tube terminating at an end face; a step projecting from the interior surface of the coupling body into the throughway; a tubular end cap engaging the coupling body for selective axial movement between a forward position and a retracted position on the coupling body; a collet at least partially disposed within the tubular end cap; an annular seal located in the coupling body adjacent to the annular step, the annular seal having a first portion and a second portion; and a sleeve movably disposed between the collet and the annular seal, the sleeve compressing the first portion of the annular seal so as to cause the second portion of the annular seal to bias against the end face of the tube when the first end of the tube is disposed within the coupling body and the tube cap is in the forward position. 14. A tube coupling as claimed in claim 13, wherein the collet biases against the sleeve so as to compress the sleeve against the seal when the end cap is moved to the forward position.15. A tube coupling as claimed in claim 13, wherein a portion of the seal encircles the first end of the tube.16. A tube coupling as claimed in claim 13, wherein the second portion of the seal comprises a substantially flat face that biases against the end face of the tube.17. A tube coupling as claimed in claim 13, wherein the collet is movably disposed within the end cap.18. A tube coupling as claimed in claim 13, wherein the step is integrally formed with the coupling body.