Tube coupling

A coupling for coupling two telescopable tubes, wherein an inner tube is telescopable into an outer tube and the outer tube has a terminal end out of which the inner tube projects, said coupling comprising:

• a receiving member emplaceable over the terminal end of the outer tube and over the section of the inner tube near the terminal end of the outer tube;
• said receiving member having a first sleeve portion with a first interior surface;
• said first sleeve portion first interior surface being generally circular in cross-section;
• said first interior surface extending over and being engageable with the exterior of the outer tube at and away from the terminal end of the outer tube;
• said receiving member having a second sleeve portion with a second interior surface;
• said second sleeve portion second interior surface being generally circular in cross-section;
• said second interior surface extending over the section of the inner tube that extends away from the terminal end portion of the outer tube;
• a tightening ring of generally circular cross-section emplaced inside said second sleeve portion and engageable with the exterior of the inner tube;
• said tightening ring being a split ring and terminating at end portions at both sides of the split in said split ring;
• said ring end portions each comprising a tab projecting away from said ring in generally the same direction and said tabs having side faces and said side faces thereof being opposed and spaced apart;
• ring tightening means in said receiving member and extending into engagement with at least one said ring end portion tab for biasing said ring end portions toward each other;
• respective engagement formations on said ring and also on said second interior surface at a location on said ring remote from said end portions thereof;
• said engagement formations being in engagement such that said ring is held stationary by means of the engagement of said engagement formations against movement around said receiving member and around the inner tube in said receiving member as said tightening means tightens said ring end portions toward each other;
• an abutment in said receiving member second sleeve portion for being engaged by and for blocking said other ring end portion from moving away from said one ring end portion as said tightening means moves said one ring end portion toward said other ring end portion;
• said tightening means being engageable with said one ring end portion to urge it toward said other ring end portion thereby to urge said ring end portions toward each other;
• said second sleeve portion having a chamber therein shaped to receive both said ring end portion tabs and said tabs being in said chamber;
• said abutment for engaging said other ring end portion being in said chamber.