Tube end expander and method of operating the same

Claim 1

A tube end expander comprising: a rotatable, tubular cage defining a plurality of generally axially extending slots; a plurality of rollers located within the cage and extending through the slots; a rotatable, tapered mandrel axially extending into the cage in frictional, driving contact with inner surfaces of the rollers; and auxiliary drive means for transmitting rotary motion from the mandrel to the cage and rollers, and including collar means defining a collar surface and including a front collar connected to the cage for rotation therewith, and a back collar connected to the mandrel for rotation therewith, and a clutch member for transmitting rotary motion from the back collar to the front collar and including a first rotatable clutch plate defining a clutch surface contiguous to and in frictional, driving contact with the collar surface for transmitting a continuum of degrees of rotary motion between the clutch and collar surfaces, a second rotatable clutch plate axially spaced from the first clutch plate and in driving engagement with the collar means to transmit rotary motion between the collar means and the second clutch plate, means connecting the first and second clutch plates for unitary rotation, and resilient means disposed between the first and second clutch plates, urging the clutch plates axially apart, and urging the clutch surface into frictional contact with the collar surface.

Claim 7

A method of operating a tube end expander of the type having a rotatable, tubular cage defining a plurality of generally axially extending slots, a plurality of rollers located within the cage and extending through the slots, a rotatable, tapered mandrel axially extending into the cage in frictional, driving contact with inner surfaces of the rollers, and an auxiliary drive means including collar means and a clutch member, wherein the collar means includes a front collar connected to the cage for rotation therewith, and a back collar connected to the mandrel for rotation therewith, and the clutch member is located between the front and back collars and includes resilient means urging the clutch member into frictional, driving engagement with the collar means to transmit rotary motion from the back collar to the front collar, the method comprising the steps of: rotating the mandrel to rotate the rollers and cage via frictional contact between the mandrel and the roller; transmitting rotational force from the mandrel to the rollers and cage via the auxiliary drive means; and adjusting the tension of the resilient means to vary the magnitude of the frictional forces between the clutch member and the collar means to modulate the degree of rotary motion transmitted from the mandrel to the rollers and cage via the auxiliary drive means.

Claim 8

A method of operating a tube end expander of the type having a rotatable, tubular cage defining a plurality of generally axially extending slots, a plurality of rollers located within the cage and extending through the slots, a rotatable, tapered mandrel axially extending into the cage in frictional, driving contact with inner surfaces of the rollers, and an auxiliary drive means including collar means and a clutch member, wherein the collar means includes a front collar connected to the cage for rotation therewith, and a back collar connected to the mandrel for rotation therewith, and the clutch member is located between the front and back collars and includes resilient means urging the clutch member into frictional, driving engagement with the collar means to transmit rotary motion from the back collar to the front collar, the method comprising the steps of: rotating the mandrel to rotate the rollers and cage via frictional contact between the mandrel and the roller; transmitting rotational force from the mandrel to the rollers and cage via the auxiliary drive means; and adjusting the tension of the resilient means to vary the magnitude of the frictional forces between the clutch member and the collar means to modulate the degree of rotary motion transmitted from the mandrel to the rollers and cage via the auxiliary drive means.