Abstract: A tube bending machine having a rotatable bend die, a pressure die, a clamp die, an actuator and a controller. A clamp assembly holds the clamp die and includes a base, a clamp die holder which is spring biased away from and slideably engageable with the base. A spacer is also attached to the base and is moveable between positions. A gear rotatably mounted to the base is attached to a first and second cam by a shaft and the gear moves on a rack. The first cam is followed by a cam follower which moves to allow the spacer to change positions. The clamp die holder may move toward the housing in case the clamp die engages an obstruction, thus avoiding damage or injury to the obstruction. A second position of the spacer substantially blocks the space between the clamp die holder and the base, thus making a substantially rigid connection between them. The second position is used during the tube bending process.

Abstract: A tube bending machine having a rotatable bend die, a pressure die, a clamp die, an actuator and a controller. A clamp assembly holds the clamp die and includes a base, a clamp die holder which is spring biased away from and slideably engageable with the base. A spacer is also attached to the base and is moveable between positions. A gear rotatably mounted to the base is attached to a first and second cam by a shaft and the gear moves on a rack. The first cam is followed by a cam follower which moves to allow the spacer to change positions. The clamp die holder may move toward the housing in case the clamp die engages an obstruction, thus avoiding damage or injury to the obstruction. A second position of the spacer substantially blocks the space between the clamp die holder and the base, thus making a substantially rigid connection between them. The second position is used during the tube bending process.

Abstract: A machine for cold bending a thick walled tube is provided which includes a rotatable bend die around which the tube is bent and a pressure die which engages an outer side wall of the tube tangential to the bend. The pressure die has a pinch-type tube groove with multiple radiuses which receives the tube and substantially prevents relative movement between the pressure die and the outer side wall of the tube. The machine also includes a pressure die boost system which linearly advances the pressure die in a forward direction as the bend die is rotated. The boost system includes a linear actuator and an electro-hydraulic control system which automatically drives the linear actuator in accordance with a pre-programmed profile of pressure and flow parameters. The linear actuator has a hydraulic cylinder with a piston, a pusher coupling the piston to the pressure die, and ports in the cylinder on opposite sides of the piston.

Abstract: A tube bending machine is provided which includes a rotatable bend die about which the tube is bent, a mandrel insertable into the tube adjacent the bend, and a mandrel rod fixed to a rear end of the mandrel. A mandrel extractor system is also included which linearly advances and retracts the mandrel. The mandrel extractor system includes a linear actuator connected to the mandrel rod and an electro-hydraulic control system which automatically drives the linear actuator at variable pressures. The linear actuator includes a hydraulic cylinder with a piston connected to the mandrel rod.

Abstract: A tube bending machine is provided which includes a rotatable bend die about which the tube is bent and a rotatable clamp die disposed outwardly of said bend die and movable to secure the tube between the clamp die and the bend die. A clamp die positioning system is provided which includes a drop-away clamp die holder supporting the clamp die, a hydraulic cylinder directly attached to the die clamp holder which advances and retracts the clamp die holder, and an electro-pneumatic control system which drives the cylinder at preselected pressures. The electro-hydraulic control system includes a hydraulic pump, a directional valve which varies the direction of flow of the hydraulic fluid to the cylinder, a proportional pressure reducing valve which varies the pressure of the hydraulic fluid, and a microprocessor controller which provides control signals to set the pressure to the preselected levels.