Rotary drill mast locking mechanism

Abstract

A locking mechanism for locking a mast includes a double acting cylinder having a piston coupled with a piston rod adapted to slide inside a cylinder barrel. The cylinder barrel is coupled with a first shaft through a first coupling pin. Mounting brackets coupled to a base plate of the mast guide a sliding motion of the first coupling pin, and the cylinder barrel. A first locking pin connected to the piston rod selectively engages a first side plate based on the sliding motion of the piston rod. A retraction stopper restricts a sliding motion of the first locking pin away from the first side plate, and subsequently causes a movement of the cylinder barrel towards the first end of the cylinder barrel. A second locking pin connected to the shaft selectively engages a second side plate based on the sliding motion of the cylinder barrel.

What is claimed is: 
     
         1 . A locking mechanism for locking a mast of a rotary drill, the locking mechanism comprising:
 a double acting cylinder, wherein the double acting cylinder comprises:
 a cylinder barrel having a first end and a second end; 
 a first barrel cover coupled to the cylinder barrel at the first end, the first barrel cover including:
 a cover adapted to be coupled to the cylinder barrel at the first end; and 
 a barrel cover shaft coupled to the cover, wherein the barrel cover shaft includes a first surface defining a first aperture; 
 
 a second barrel cover coupled to the cylinder barrel at the second end; 
 a piston adapted to perform a sliding motion inside the cylinder barrel between the first end and the second end; and 
 a piston rod coupled to the piston, the piston rod adapted to slide in a first direction and a second direction relative to the second end of the cylinder barrel; 
   a first coupling mechanism for coupling the first barrel cover to a first shaft towards the first end of the cylinder barrel, wherein the first coupling mechanism includes:
 a first cover member having a first cover surface defining a first coupling pin hole, and a first shaft opening adapted to receive the first shaft therein; and 
 a first coupling pin passing through the first coupling pin hole and the first aperture of the barrel cover shaft such that the first coupling pin couples the first cover member and the barrel cover shaft, wherein the first coupling pin has a first end and a second end extending out from the first coupling pin hole; 
   a pair of mounting brackets coupled to a base plate of the mast, the pair of mounting brackets comprising:
 a first mounting bracket having a first bracket surface defining a first slot, wherein the first slot has a first end and a second end; and 
 a second mounting bracket having a second bracket surface defining a second slot, wherein the second slot has a third end and a fourth end; 
 wherein the first slot allows the first end of the first coupling pin to slide inside the first slot between the first and second ends of the first slot, and the second slot allows the second end of the first coupling pin to slide inside the second slot between the third and fourth ends of the second slot such that a sliding motion of the first coupling pin, and subsequently a sliding motion of the cylinder barrel is guided by the first slot and the second slot; 
   a first locking pin connected to the piston rod, and adapted to selectively engage a first side plate based on the sliding motion of the piston rod;   a retraction stopper mounted on the base plate of the mast, wherein the retraction stopper is adapted to restrict an extent of sliding motion of the first locking pin in a second direction, and adapted to subsequently cause a movement of the cylinder barrel in the first direction;   a second locking pin connected to the first shaft, and adapted to selectively engage a second side plate based on the movement of the cylinder barrel;   wherein the mast of the rotary drill is locked when the first locking pin and the second locking pin are engaged with the first side plate and the second side plate respectively; and   wherein the mast of the rotary drill is unlocked when the first locking pin and the second locking pin are disengaged with the first side plate and the second side plate respectively.   
     
     
         2 . The locking mechanism of  claim 1 , further comprising a second shaft coupled to the piston rod towards the second end of the cylinder barrel such that the second shaft transfers motion of the piston rod to the first locking pin. 
     
     
         3 . The locking mechanism of  claim 2 , wherein the second shaft is coupled to the piston rod through a second coupling mechanism, the second coupling mechanism includes:
 a second cover member having a second cover surface defining a second shaft opening adapted to receive the second shaft therein; and   a second coupling pin passing through the second cover member and the second aperture in a piston rod surface defined by the piston rod such that the second coupling pin couples the second cover member and the piston rod.   
     
     
         4 . The locking mechanism of  claim 1 , wherein the first locking pin locks with a first lock nut at one end to selectively restrict an extent of movement of the first locking pin in the second direction by abutting against the retraction stopper. 
     
     
         5 . The locking mechanism of  claim 1 , wherein at least one mounting bracket from the pair of mounting brackets is coupled to the base plate by a mechanical fastener. 
     
     
         6 . The locking mechanism of  claim 1 , wherein at least one mounting bracket from the pair of mounting brackets is welded to the base plate. 
     
     
         7 . The locking mechanism of  claim 1 , wherein the first side plate has a surface defining a plurality of angularly spaced openings such that in a locked condition the first locking pin slides into one of the plurality of angularly spaced openings to engage the first side plate to lock the mast in a corresponding angular position. 
     
     
         8 . The locking mechanism of  claim 1 , wherein the second side plate has a surface defining a plurality of angularly spaced openings such that in a locked condition the second locking pin slides into one of the plurality of angularly spaced openings to engage the second side plate to lock the mast in a corresponding angular position. 
     
     
         9 . A rotary drill comprising:
 a chassis supported over a ground engaging mechanism;   a first side plate coupled to the chassis;   a second side plate coupled to the chassis;   a mast provided between the first side plate and the second side plate;   a base plate coupled to the mast towards a bottom end of the mast; and   a locking mechanism for locking the mast with the first side plate and the second side plate, the locking mechanism comprising:
 a double acting cylinder, wherein the double acting cylinder comprises:
 a cylinder barrel having a first end and a second end; 
 a first barrel cover coupled to the cylinder barrel at the first end, the first barrel cover including:
 a cover adapted to be coupled to the cylinder barrel at the first end; and 
 a barrel cover shaft coupled to the cover, wherein the barrel cover shaft includes a first surface defining a first opening; 
 
 a second barrel cover coupled to the cylinder barrel at the second end; 
 a piston adapted to perform a sliding motion inside the cylinder barrel between the first end and the second end; and 
 a piston rod coupled to the piston, the piston rod adapted to slide in a first direction and a second direction relative to the second end of the cylinder barrel; 
 
 a first coupling mechanism for coupling the barrel cover to a first shaft towards the first end of the cylinder barrel, wherein the first coupling mechanism includes:
 a first cover member having a first cover surface defining a first coupling pin hole, and a first shaft opening adapted to receive the first shaft therein; and 
 a first coupling pin passing through the first coupling pin hole and the first aperture of the barrel cover shaft such that the first coupling pin couples the first cover member and the barrel cover shaft, wherein the first coupling pin has a first end and a second end extending out from the first coupling pin hole; 
 
 a pair of mounting brackets coupled to a base plate of the mast, the pair of mounting brackets comprising:
 a first mounting bracket having a first bracket surface defining a first slot, wherein the first slot has a first end and a second end; and 
 a second mounting bracket having a second bracket surface defining a second slot, wherein the second slot has a third end and a fourth end; 
 wherein the first slot allows the first end of the first coupling pin to slide inside the first slot between the first and second ends of the first slot, and the second slot allows the second end of the first coupling pin to slide inside the second slot between the third and fourth ends of the second slot such that a sliding motion of the first coupling pin, and subsequently a sliding motion of the cylinder barrel is guided by the first slot and the second slot; 
 
 a first locking pin connected to the piston rod, and adapted to selectively engage the first side plate coupled to the chassis based on the sliding motion of the piston rod; 
 a retraction stopper mounted on the base plate of the mast, wherein the retraction stopper is adapted to restrict an extent of sliding motion of the first locking pin in the second direction, and adapted to subsequently cause movement of the cylinder barrel in the first direction; 
 a second locking pin connected to the first shaft, and adapted to selectively engage the second side plate coupled to the chassis based on the movement of the cylinder barrel; 
 wherein the mast of the rotary drill is locked when the first locking pin and the second locking pin are engaged with the first side plate and the second side plate respectively; and 
 wherein the mast of the rotary drill is unlocked when the first locking pin and the second locking pin are disengaged with the first side plate and the second side plate respectively. 
   
     
     
         10 . The rotary drill of  claim 9 , further comprising a second shaft coupled to the piston rod towards the second end of the cylinder barrel such that the second shaft transfers motion of the piston rod to the first locking pin. 
     
     
         11 . The rotary drill of  claim 10 , wherein the second shaft is coupled to the piston rod through a second coupling mechanism, the second coupling mechanism includes:
 a second cover member having a second cover surface defining a second shaft opening adapted to receive the second shaft therein; and   a second coupling pin passing through the second cover member and a second aperture in a piston rod surface defined by the piston rod such that the second coupling pin couples the second cover member and the piston rod.   
     
     
         12 . The rotary drill of  claim 9 , wherein the first locking pin locks with a lock nut at one end to selectively restrict an extent of movement of the first locking pin in the second direction from the first side plate by abutting against the retraction stopper. 
     
     
         13 . The rotary drill of  claim 9 , wherein at least one mounting bracket from the pair of mounting brackets is coupled to the base plate by a mechanical fastener. 
     
     
         14 . The rotary drill of  claim 9 , wherein at least one mounting bracket from the pair of mounting brackets is welded to the base plate. 
     
     
         15 . The rotary drill of  claim 9 , wherein the first side plate has a surface defining a plurality of angularly spaced openings such that in a locked condition the first locking pin slides into one of the plurality of angularly spaced openings to engage the first side plate to lock the mast in a corresponding angular position. 
     
     
         16 . The rotary drill of  claim 9 , wherein the second side plate has a surface defining a plurality of angularly spaced openings such that in a locked condition the second locking pin slides into one of the plurality of angularly spaced openings to engage the second side plate to lock the mast in a corresponding angular position. 
     
     
         17 . A method for locking a mast of the rotary drill, the method comprising;
 supplying an actuating fluid to a first opening of a double acting cylinder, wherein the double acting cylinder has a cylinder barrel, and a piston rod coupled to a piston adapted to slide inside the cylinder barrel;   moving a first locking pin coupled with the piston rod, through the movement of the piston rod due to force applied by the actuating fluid, to engage a first side plate; and   moving a second locking pin coupled with the double acting cylinder, through the movement of the cylinder barrel of the double acting cylinder, to engage a second side plate, wherein the mast of the rotary drill is locked when the first locking pin and the second locking pin are engaged with the first side plate and the second side plate respectively.   
     
     
         18 . The method of  claim 17  further comprising:
 supplying the actuating fluid to a second opening of the double acting cylinder; 
 moving the first locking pin coupled with the piston rod, through the movement of the piston rod, to disengage from the first side plate, wherein an extent of motion of the first locking pin is restricted by a retraction stopper; and 
 moving the second locking pin coupled with the double acting cylinder, through the movement of the cylinder barrel of the double acting cylinder, to disengage from the second side plate, wherein the movement of the cylinder barrel is restricted by abutment of the first coupling pin with the first end of the first slot and the third end of the second slot, and wherein the mast of the rotary drill is unlocked when the first locking pin and the second locking pin are disengaged with the first side plate and the second side plate respectively. 
 
     
     
         19 . The method of  claim 18 , wherein moving the second locking pin coupled with the double acting cylinder further comprises:
 moving the second locking pin, through the movement of the cylinder barrel, wherein the cylinder barrel is coupled to the second locking pin through a first shaft.   
     
     
         20 . The method of  claim 17 , wherein moving the first locking pin coupled with the piston rod further comprises:
 moving the first locking pin, through the movement of a second shaft, wherein the second shaft couples the piston rod with the first locking pin.