Abstract:
A device for remotely actuating the safety lock of individual oil pumping apparatuses, (also known as AIB) employed in oil wells for extraction of this fluid. The actuating device or locking device permitting to an AIB operator to remotely actuate a safety lock for locking the entire movement of the AIB, without the need that the operator go upwards the AIB to a zone wherein the safety lock is usually housed. For this purpose the locking device includes an actuator for moving upwardly and downwardly the safety lock. The locking device also including an indicator for indicating the position of the safety lock.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a device for remotely actuating the safety lock of individual oil pumping apparatuses. These individual oil pumping apparatuses are generally called AIB, also known as storks and little horses. 
         [0002]    The rectilinear pumping movement of the AIB is generated by a motor, such as an electric motor, explosion engine or the like actuating over a mechanism for transforming movement. When it is necessary to stop the operation of these pumping apparatuses, either for operative questions or for service maintenance, the person operating the AIB must follow a sequence of steps for permitting the personnel to operate the AIB in a safety manner. 
         [0003]    First, the electric motor is stopped, then a brake is actuated generally by operating a lever that prevents the pumping movement of the AIB. This is necessary because while the motor movement has been stopped there are still vertical movements of the pumping head generated by the weight and/or inertia of the movement of the moving parts of the AIB. Finally, for really guarantying the safety of any operation in the AIB and while the brake has already been actuated it is necessary to place a safety lock into a locking position. This last step really guarantees that the AIB is kept completely immobilized. 
         [0004]    Some people without knowledge of the art and without knowledge of the weights and sizes involved in an individual pumping apparatus may find the safety locking operation in the AIB unnecessary. However, this conclusion is absolutely erroneous as long as the parts conforming the individual pumping apparatuses are really big not only in volume but also in mass parameters. This is evident when paying attention to the side counterweights employed in an AIB. 
         [0005]    Indeed, because of the complex morphology of the individual pumping apparatuses and since the same operate under really adverse conditions, that is outdoor, subject to extreme temperatures, to sand, dust, wind, snow, etc. the service and maintenance operations are very frequent. In addition, generally these operations are very complex and dangerous for the operators involved in the same. 
       DESCRIPTION OF THE PRIOR ART 
       [0006]    Today, an operator follows the above described locking steps to safely guarantee that an individual pumping apparatus is completely stopped and is stable. It happens that in the last step, namely the location of the safety lock into the “locking” position, the operator must literally climb the AIB structure. This is because the safety lock is located in a reduction box placed at a height that some times exceeds the 2 meters. Concretely, it may be said that the safety lock is really safe but what is unsafe in the operation, in fact extremely unsafe if considered the weather under which the operations are carried out, is the action that must be performed by the operator to accede to the safety lock for placing the same into the “locking” position. In like manner, but following the inverse procedure, once the maintenance operations have been finished the operator is again exposed to a risky situation when he/she has to place said lock into an “unlocking” position. 
         [0007]    It is known that due toe the means provided by the prior art many accidents have occurred to the operators and, some times, these accidents have been fatal ones. 
         [0008]    The present invention is aimed to solve the inconveniences related to the unsafe situations, including comfort, as occurring in the prior art. 
       SUMMARY OF THE INVENTION 
       [0009]    It is therefore an object of the invention to provide a device for remotely actuating the safety lock of individual oil pumping apparatuses, wherein the device is capable of permitting the operator to actuate the safety lock in a safe manner, thus preventing the operator to enter into contact with the large mechanism of the AIB. 
         [0010]    It is still another object of the present invention to provide a device for remotely actuating the safety lock of individual oil pumping apparatuses, wherein the device is capable of permitting the operator to verify the position of the safety lock without the need of entering into contact with the same, with the verification being made through means for indicating the position of said lock. 
         [0011]    It is a further object of the present invention to provide a device for remotely actuating the safety lock of individual oil pumping apparatuses, wherein the device is capable of being put into practice in an easy manner without practically increasing the costs of the individual oil pumping apparatus wherein the device is installed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    For better clarity and comprehension of the object of the present invention a preferred embodiment of the same has been illustrated by way of example in the following drawings wherein: 
           [0013]      FIG. 1  schematically shows a side elevation view of an individual pumping apparatus or AIB. 
           [0014]      FIG. 2  shows a detail of the parts conforming a locking device according to the prior art. 
           [0015]      FIG. 3  shows the locking device of  FIG. 2  including a remote actuating device according to a first exemplary embodiment (hydraulic) of the present invention. 
           [0016]      FIG. 4  shows the locking device of  FIG. 2  including a remote actuating device according to a second exemplary embodiment (mechanical) of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    First, reference to  FIG. 1  will be made where a side elevation schematic view of the individual pumping apparatus is shown and indicated with the general reference number  1 . General reference number  2  indicates a locking device (not illustrated in this Figure) as it is known in the prior art. It can be easily have a view of the magnitude of the AIB  1  and it is possible to appreciate the possible lesions that an operator can suffer if he/she is impacted by some of the AIB parts, such as counterweights  3  and  4 . 
         [0018]      FIG. 2  permits to clearly identify the parts conforming a locking device  2  as it is know in the prior art. 
         [0019]    As it was explained above, the individual pumping apparatuses are of the type employed in the oil wells for extraction of petroleum and they are known as storks, little horses or AIBs. Each AIB includes a motor means which can be an electrical motor, an engine, a pneumatic motor, or the like, which motor means is connected to a reduction box  5 . The output of this box is defined by an output shaft  6  operatively connected to a mechanism for general movement of the AIB. The movement of shaft  6 , and hence the movement of the moving parts of the AIB, are alternatively restricted by means of a brake operated by means of a lever indicated by reference number  7  in  FIG. 1 . Furthermore, this movement may be locked by locking device  2  (located in the upper middle part of the AIB). 
         [0020]    Locking device  2  basically consists of a safety lock  7  including an end  8  rotatably connected to said reduction or gear box and a second end  9  vertically movable and alternatively resting and locking into at least one peripheral groove of a toothed disc  10 . Toothed disc  10  is fixedly connected to output shaft  6  of reduction box  5 . 
         [0021]    When lock  10  is in a lower position, that is when it is locked into one groove of disc  10 , a locking position or condition for the AIB is defined. On the other hand, when lock  7  is in an upper position, a unlocking position or condition of the AIB is defined. 
         [0022]    The present invention is based in the provision of a remote actuating device for the locking device, or more precisely, a provision of a lifting means for moving upwardly and downwardly safety lock  7 . This also permits an operator located in the lower or bottom portion of the AIB to easily actuate said means for moving upwardly and downwardly. 
         [0023]    Now referring to  FIG. 3  wherein locking device  22  is shown, it may be seen that the same is very similar to locking device  2  of  FIG. 2 , but differing from device  2  in that it includes the device for remote actuation of safety lock  7 . This lifting means consists of a hydraulic pump  23  that may be operated or actuated by actuating means  24  arranged in the lower part of the AIB. Pump  23  is connected to a couple of hoses  25  and  26  which in turn are connected to a hydraulic cylinder  27 . Hydraulic cylinder  27  includes a two-position piston  28  located just below vertically moving end  9  of safety lock  7 . In addition, the piston has a longitudinal axis that is substantially coincident with the gravity vector, that is, it is normal to the floor where the AIB is installed. 
         [0024]    When piston  28  is extended, safety lock  7  will be in an upper position, that is, unlocking the movement of AIB  1 . On the other hand, when piston  28  is in its resting position safety lock will be in a lower position, that is, locking the movement of the AIB  1 . 
         [0025]    In the exemplary embodiment of  FIG. 3  actuating means  24  is a three-position valve for switching the hydraulic circuit defined by pump  23 , hoses  25  and  26  and hydraulic cylinder  27 . However, actuating means may be defined by a three-position electric switch for switching the electric circuit (not illustrated) of the hydraulic pump, as well as actuating means may be defined by any other actuator permitting to bi-directionally operate or actuate a hydraulic circuit, either directly or indirectly. 
         [0026]      FIG. 4  shows a second embodiment wherein a locking device is shown, this time remotely actuated by a mechanical arrangement. 
         [0027]    In this embodiment the lifting means for moving upwardly and downwardly safety lock  7  consists of a rotating crank  43  arranged in the lower part of the AIB  1 . This crank is mechanically connected to three rods  44 ,  45  and  46  for transferring the rotation of crank  43 . Rods  44 ,  45  and  46  are connected to each other by crossheads  47  and  48 . In addition, rod  46 , namely the rod located at a greater distance from rotating crank  43  is mechanically connected to a endless screw  49  which is capable of rotating within a threaded bushing  50 . Endless screw  49  is located just below vertically moving end  9  of safety lock  7 , the screw having a longitudinal axis thereof arranged in coincidence to the gravity vector, that is geometrically normal to the floor (like piston  28  of  FIG. 3 ). 
         [0028]    The above disclosed arrangement permits safety lock  7  to be located or placed in the upper position when screw  49  is extended and it will be placed in the lower position when screw  49  is substantially retracted into the bushing  50 . 
         [0029]    Locking means  22  shown in  FIG. 3  as well as its equivalent one shown in  FIG. 4  may be provided of an indicator means for indicating the position of safety lock  7 . For better clarity and easy disclosure only the description of the operation of this indicator will be made by use of  FIG. 3 . 
         [0030]    As may be appreciated, locking device  22  includes a steel wire  60  movable into a sheath  61  and connected, at a first end thereof, to vertically moving end  9  of safety lock  7 . At a second end thereof, steel wire  60  is connected to indicator means  62  for indicating the position of safety lock  7 . Indicator means  62  is located and arranged in the lower part of the AIB and it is moved by steel wire  60  between a position indicating that safety lock  7  is at its lower position, and a second position indicating that safety lock  7  is in its upper position. The possible movement of indicator means  62  is indicated by arrows A and B. 
         [0031]    It is not necessary to remark that the purpose of indicator means  62  is to inform the operator of AIB  1  about the locking condition of the AIB, therefore indicator means  62  is easily viewed by the operator. 
         [0032]    In embodiments with minimal variations it is contemplated the possibility that indicator means  62  may be alternatively anchored in any of the two positions of safety lock  7  that are indicated by the indicator means. This may be achieved, for example, by providing indicator means with orifices that are coincident with orifices in a plate fixed to the AIB, through which orifices a padlock can be placed, for example, for preventing any movement possibility. 
         [0033]    As any person skilled in the art may understand it would be clear that the present patent application aims to disclose the concept of the invention. However, many variations are contemplated in the present invention, such as variations of sizes, materials, number of employed pistons, type of safety lock, cranks, hydraulic valves, use of electric actuators including actuators intelligently controlled by modern electronics, etc. Therefore, all these variants and/or modifications, as well as any other variants and/or modifications that may be naturally put in practice, are included in the concept of the present invention.