Pneu/hydraulic tube flaring tool apparatus and method

Abstract

A pneumatic-hydraulic tube flaring tool includes a pneumatic actuator, a hydraulic actuator coupled to the pneumatic actuator, a ram coupled to the hydraulic actuator, and a plurality of die elements. A tube is clamped between the two die elements, which are then clamped inside a casing that is attached to an actuator housing. Compressed air is introduced into the pneumatic actuator on a pressure side of a pneumatic piston. The pneumatic piston actuates a hydraulic plunger in order to actuate a hydraulic piston which applies a force to the ram. The distal end of the ram and the aggregate end of the die elements are shaped to form a flared tube end. The ram impinges the end of the tube and plastically deforms the tube end between the ram and the die elements forming a flared tube end.

1 . A tube flaring device, comprising: 
 a pneumatic actuator;    a hydraulic actuator operatively connected to the pneumatic actuator;    a ram mechanically coupled to the hydraulic actuator, a distal end of the ram including an interior portion of a shape to form a flared tube end; and    a plurality of die elements, a proximal aggregate end of which includes an exterior portion of the shape to form the flared tube end,    wherein the pneumatic actuator actuates the hydraulic actuator, which in turn actuates the ram to form the flared tube end.    
   
   
       2 . The tube flaring device of  claim 1 , further comprising a substantially cylindrical plunger attached to the pneumatic actuator at a first end and introduced into a cylindrical bore at a second end, wherein the plunger reciprocates within the bore when the pneumatic actuator is actuated, exerting a force upon a hydraulic fluid in the bore that results in an increased pressure within the hydraulic fluid, which pressure actuates the hydraulic actuator.  
   
   
       3 . The tube flaring device of  claim 1 , wherein an aggregate interior surface of the plurality of die elements defines a central bore whereby a tube having a tube end is clamped between the plurality of die elements and held in place while the ram impinges the tube end to form the flared tube end.  
   
   
       4 . The tube flaring device of  claim 1 , further comprising: 
 an actuator housing that encloses the pneumatic actuator and the hydraulic actuator; and    a casing that attaches to the actuator housing to hold the ram and the plurality of die elements, a tube having a tube end being introduced into the casing.    
   
   
       5 . The tube flaring device of  claim 4 , further comprising an opening in a wall of the casing that allows insertion of the ram and the plurality of die elements into the casing.  
   
   
       6 . The tube flaring device of  claim 4 , further comprising: 
 a threaded hole in a wall of the casing; and    a clamping screw that extends through the threaded hole, the clamping screw including a clamping surface at a distal end that contacts at least one of the plurality of die elements, whereby the plurality of die elements are held in place between the clamping surface and an opposite wall of the casing.    
   
   
       7 . The tube flaring device of  claim 4 , wherein the pneumatic actuator comprises: 
 a pneumatic piston of substantially cylindrical shape including a pressure side and a back side;    a cylindrical cavity within the actuator housing, wherein the pneumatic piston is configured to slide toward a distal end of the cavity when a compressed gas is applied to the pressure side of the pneumatic piston;    a sealing surface between the pneumatic piston and a cavity wall;    a resilient element biasing the pneumatic piston in the direction of a proximal end of the cavity; and    an orifice in the cavity wall to introduce the compressed gas into the cavity on the pressure side of the pneumatic piston.    
   
   
       8 . The tube flaring device of  claim 7 , wherein the resilient element comprises a helical spring.  
   
   
       9 . The tube flaring device of  claim 7 , further comprising: 
 an interior cylindrical surface in the actuator housing defining a cylindrical bore including an open end;    a substantially cylindrical slide valve configured to reciprocate within the bore that protrudes from the open end of the bore;    a first sealing surface around a circumference of the slide valve at an inward location along the axis of the slide valve;    a second sealing surface around the circumference of the slide valve at an outward location along the axis of the slide valve;    an inlet channel including a first end that opens into the bore at a first location along the axis of the bore and a second end that opens into a generally cylindrical threaded socket for attaching a pneumatic fitting;    a supply channel including a third end that opens into the bore at a second location along the axis of the bore and a fourth end that opens into the cavity at the orifice; and    an exhaust channel including a fifth end that opens into the bore at a third location along the axis of the bore and a sixth end that is open to the atmosphere,    wherein the slide valve permits fluid communication between the inlet channel and the supply channel when the slide valve is moved to an inward position but not when the slide valve is moved to an outward position, and between the supply channel and the exhaust channel when the slide valve is moved to an outward position but not when the slide valve is moved to an inward position, such that the compressed gas may be selectively introduced to the cavity or exhausted to the atmosphere by movement of the slide valve.    
   
   
       10 . The tube flaring device of  claim 9 , further comprising: 
 a trigger lever coupled to the actuator housing that contacts the protruding slide valve to apply a trigger force to move the slide valve in an inward direction with respect to the bore; and    a valve return resilient element that contacts the slide valve to apply a valve return force to the slide valve in an outward direction with respect to the bore,    wherein the slide valve is configured to be closed when positioned toward the outward direction and open when positioned toward the inward direction.    
   
   
       11 . The tube flaring device of  claim 4 , wherein the hydraulic actuator comprises: 
 a hydraulic piston of generally cylindrical shape including a pressure side and a back side;    a cylindrical cavity within the actuator housing, wherein the hydraulic piston slides toward a distal end of the cavity when a pressurized hydraulic fluid is applied to the pressure side of the hydraulic piston;    a sealing surface between the hydraulic piston and a cavity wall; and    a resilient element biasing the hydraulic piston to resist translation of the hydraulic piston in the direction of the distal end of the cavity,    wherein a hydraulic fluid is introduced into the cavity on the pressure side of the hydraulic piston.    
   
   
       12 . The tube flaring device of  claim 11 , wherein the resilient element comprises a helical spring.  
   
   
       13 . The tube flaring device of  claim 11 , wherein the hydraulic piston includes a cylindrical appendage extending axially from a central portion of the back side of the hydraulic piston through an aperture to contact the ram outside the cavity and apply an axial force to the ram.  
   
   
       14 . The tube flaring device of  claim 1 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a 45-degree double-flared tube end.  
   
   
       15 . The tube flaring device of  claim 1 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a “bubble” flared tube end.  
   
   
       16 . The tube flaring device of  claim 1 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a “push-connect” type flared tube end.  
   
   
       17 . A method of forming a flared tube end, comprising the steps of: 
 clamping a tube having a tube end between a plurality of die elements that include an aggregate interior surface defining a central bore to hold the tube in place, the plurality of die elements including a proximal aggregate end including an exterior portion of a shape to form a flared tube end;    channeling a compressed gas into a cavity on a pressure side of a pneumatic piston to actuate the pneumatic piston;    actuating a plunger to apply a force to a hydraulic fluid in a cylindrical bore on a pressure side of a hydraulic piston to actuate the hydraulic piston; and    actuating a ram to impinge the tube end, a distal end of the ram including an interior portion of the shape to form the flared tube end.    
   
   
       18 . The method of  claim 17 , wherein a  45 -degree double-flared tube end is formed.  
   
   
       19 . The method of  claim 17 , wherein a “bubble” flared tube end is formed.  
   
   
       20 . The method of  claim 17 , wherein a “push-connect” type flared tube end is formed.  
   
   
       21 . A tube flaring device, comprising: 
 means for clamping a tube having a tube end between a plurality of die elements that include an aggregate interior surface defining a central bore to hold the tube in place, the plurality of die elements including a proximal aggregate end including an exterior portion of a shape to form a flared tube end;    means for channeling a compressed gas into a cavity on a pressure side of a pneumatic piston to actuate the pneumatic piston;    means for actuating a plunger to apply a force to a hydraulic fluid in a cylindrical bore on a pressure side of a hydraulic piston to actuate the hydraulic piston; and    means for actuating a ram to impinge the tube end and form a flared tube end, a distal end of the ram including an interior portion of the shape to form the flared tube end.    
   
   
       22 . The tube flaring device of  claim 21 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a 45-degree double-flared tube end.  
   
   
       23 . The tube flaring device of  claim 21 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a “bubble” flared tube end.  
   
   
       24 . The tube flaring device of  claim 21 , wherein the interior portion of the shape of the distal end of the ram and the exterior portion of the shape of the proximal aggregate end of the plurality of die elements correspond to a “push-connect” type flared tube end.