Abstract:
A connector having a stinger and a receiver. The receiver is cocked by applying counter-acting torques to separate sections of the receiver. The counteracting torques compress a spring member. In the cocked position, the stinger is inserted into the receiver. When the counter-acting torques are released, the spring decompresses and locks the stinger in the receiver.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to a mechanism and method for securely and quickly connecting two members. One application for such connectors is with the Completion Insertion and Retrieval under Pressure system, herein referred to as CIRP system currently offered by Schlumberger Perforating and Testing. The Schlumberger CIRP system is used to insert tools in a pressurized wellbore. The connector used in the existing CIRP system uses a conventional spiral wound wire spring to maintain the connector in its locked position. 
     SUMMARY OF THE INVENTION 
     In some applications, it may be desirable to increase the torque available to keep a connector in its locked position. Increased torque may be advantageous in a CIRP system because the connector may be subject to extreme forces. Also, as the connector diameter decreases, the engagement torque available from a conventional spiral wound wire spring decreases significantly because the usable spring size is reduced. 
     One embodiment of the present invention provides a significant increase in the torque available to secure a connector in a locked position as compared to the torque available from a similarly sized conventional spiral wound wire spring. Because one embodiment of the present invention provides increased torque density, smaller connectors are possible that have sufficient engagement torque to remain in their locked position in abusive environments. 
     Another embodiment is a connector having a receiver. The receiver has a receiver gripping surface at a first end and a fork at a second end. A stinger has a stinger fork that is concentric with and adjacent the receiver fork. A sleeve has a first end adjacent the receiver fork and a sleeve gripping surface at its second end. The sleeve is rotationally engageable with the receiver fork. A first cam is connected to the sleeve remote from the sleeve gripping surface. The first cam is concentric with and adjacent the receiver. A cam engagement member is adjacent the first cam. The cam engagement member slidingly engages the first cam. The cam engagement member is also adjacent the receiver and is rotationally restrained relative to the receiver. A compressive member support is connected to the receiver. Interposed between the compressive member support and the first cam is a compressive member. 
     In an alternative embodiment of the invention, the above-described first cam has a helical surface that is inclined approximately 20 to 30 degrees from a plane perpendicular to the axis of the receiver. 
     In another alternative embodiment, the above-described stinger fork has stinger fork teeth on its exterior surface, and the above-described receiver has receiver fork teeth on its exterior surface. The stinger fork teeth and receiver fork teeth slidingly engage sleeve teeth on the interior surface of the above-described sleeve. 
     In yet another alternative embodiment, a protective member is connected to the receiver and circumscribes the above-described first cam, cam engagement member, and compressive member. 
     In another embodiment of the invention, a connector has a receiver. The receiver has a gripping surface at its first end and a receiver fork at the second end. A stinger has a stinger fork adjacent the receiver fork. A sleeve has a first end adjacent the receiver fork and a sleeve gripping surface at a second end. The sleeve is rotationally engageable with the receiver fork and the stinger fork. A first cam is connected to the sleeve remote from the sleeve gripping surface. The first cam is concentric with and adjacent the receiver. Also, the first cam is axially restrained relative to the receiver. A second cam is adjacent the first cam. The second cam slidingly engages the first cam. The second cam is concentric with and adjacent the receiver, and the second cam is rotationally restrained relative to the receiver. A spring ring support is connected to the receiver. A spring ring is interposed between the second cam and the spring ring support. 
     In another embodiment, a connector has a receiver. The receiver has a plurality of pinion teeth at a first end and a plurality of forks at a second end. A stinger has a plurality of stinger forks that are adjacent the receiver forks. A locking sleeve has a first end adjacent the receiver forks. The locking sleeve has a plurality of pinion teeth at a second end. The locking sleeve is rotationally engageable with receiver forks and stinger forks. The locking sleeve is connected to a first cam remote from the locking sleeve pinion teeth. The first cam is concentric with and adjacent the receiver, and the first cam is axially restrained relative to the receiver. A second cam is adjacent the first cam. The second cam slidingly engages the first cam. The second cam is concentric with and adjacent the receiver, and is rotationally restrained relative to the receiver. A spring ring support is connected to the receiver, and a plurality of spring rings are interposed between the second cam and the spring ring support. 
     Another embodiment of the present invention involves a method of connecting two members. A first section of the receiving member is secured. A second section of the receiving member is rotated relative to the first section from an uncocked position to a cocked position. The rotation of the receiving member axially compresses a compressive member. A stinger member is inserted into the receiving member and the receiving member is then returned to its uncocked position, which axially decompresses the compressive member. The return of the second receiving member section to its uncocked position locks the stinger member in engagement with the receiving member. 
     The scope and applicability of the present invention will be apparent from the claims following the detailed description. It should be understood that the detailed description and examples given represent embodiments of the present invention and are given by way of illustration only. Various changes and modifications within the spirit and scope of the invention will be obvious. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of one embodiment of the present invention. 
     FIG. 2 is a perspective view of a feature of an embodiment of the present invention. 
     FIG. 3 is an elevation view of certain aspects of an embodiment of the present invention. 
     FIG. 4 is a cut-a-way perspective view of an aspect of an embodiment of the present invention. 
     FIG. 5 is an exploded perspective view of features of one embodiment of the present invention. 
     FIG.  6   a  is a perspective view of features of one embodiment of the present invention. 
     FIG.  6   b  is a perspective view of features of one embodiment of the present invention. 
     FIG. 7 is a cut-a-way exploded perspective view of aspects of one embodiment of the present invention. 
     FIG. 8 is a cut-a-way perspective view of aspects of one embodiment of the present invention. 
     FIG. 9 is an exploded cut-a-way perspective view of aspects of an embodiment of the present invention. 
     FIG. 10 is a cut-a-way perspective view of an embodiment of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 depicts one embodiment of the present invention. A stinger  12  is inserted into a receiver  14  to form a connector  16 . 
     FIG. 2 depicts a receiver body  18 . At one end of the receiver body  18  are a plurality of receiver body pinion teeth  20 . A plurality of pins  22  protrude from the receiver body  18  and a snap ring  24  is positioned in a groove in the receiver body  18  (the groove is not shown). In this embodiment, four receiving forks  26  are formed in the receiver body  18  opposite the receiver body pinion teeth  20 . In other embodiments, different numbers of receiver forks may be used. For example, one embodiment has six receiver forks. A plurality of receiver fork teeth  28  are formed in the exterior surface of each receiver fork. The receiver forks  26  are spaced around the circumference of the receiver body  18 , preferably such that a receiver fork is diametrically opposite another receiver fork. 
     FIG. 3 depicts a section of the receiver body  18 . A protective shell  30  is connected to the receiver body  18 . In this embodiment the protective shell  30  is connected to the receiver body  18  through a spring ring support  32 . In one embodiment, the protective shell  30  has an exterior diameter greater than the receiver body pinion teeth  20  and covers the receiver  14  up to the receiver body pinion teeth  20 . The spring ring support  32  is adjacent a spring ring  34  and prevents axial movement of the adjacent spring ring  34  relative to the receiver body  18 . A plurality of spring rings  34  are concentric with the receiver body  18  and are interposed between the receiver body  18  and the protective shell  30 . 
     A first cam  36  is adjacent the snap ring  24 . The snap ring  24  prevents axial movement of the first cam  36  relative to the receiver body  18 . The first cam  36  is concentric with the receiver body  18  and is free to rotate relative to the receiver body  18 . The first cam  36  has a plurality of first cam tongues  38  that extend towards the receiver forks  26  and are interposed between the snap ring  24  and the protective shell  30 . Opposite the first cam tongues  38  are a plurality of first cam stops  40  and a plurality of first cam helical surfaces  42 . 
     A second cam  44  is interposed between the first cam  36  and the plurality of spring rings  34 . The second cam  44  is shown in cross-section in FIG.  3 . The second cam  44  has a plurality of grooves  46  that slidingly engage the pins  22  protruding from the receiver body  18 . The pins  22  and second cam grooves  46  engage to prevent rotational movement of the second cam  44  relative to the receiver body  18 , while permitting axial movement of the second cam  44  relative to the receiver body  18 . The second cam  44  has a plurality of second cam stops  48  and a plurality of second cam helical surfaces  50 . 
     The second cam helical surfaces  50  slidingly engage the first cam helical surfaces  42  and, upon counter-clockwise rotation of the first cam  36 , the second cam  44  compresses the plurality of spring rings  34 . In one embodiment, the cam helical surfaces  42 ,  50  are inclined  20  to  30  degrees from a plane perpendicular to the receiver body  18  axis. The cam stops  40 ,  48  prevent clockwise rotation of the first cam  36  relative to the second cam  44  past a predetermined rest point. In one embodiment, the spring rings  34  may carry a compressive load when the first cam stop  40  is adjacent the second cam stop  48 . 
     In an alternative embodiment, the spring rings  34  are supported by a shoulder threadingly connected to the receiver body  18  and the first cam  36  abuts against a shoulder formed in the receiver body  18 . 
     FIG. 4 depicts a partial cut-a-way of spring rings  34 . The spring rings  34  are commercially available from Ringfeder Corp. of Westwood, N.J. in a variety of sizes and configurations. The spring rings  34  are a plurality of stackable external and internal rings  34   a,    34   b.  When stacked, the rings engage at alternating conical surfaces  52 . Upon compression of the stack, the external spring rings  34   a  are subject to an expanding force and the internal spring rings  34   b  are subject to a compressive force. In one embodiment, the spring rings  34  are made of beryllium copper or bronze. In an another embodiment, the spring rings  34  are protected by a sleeve. 
     FIG. 5 is an exploded view of the spring rings  34 , first and second cams  36 ,  44 , and the locking sleeve  54 . Locking sleeve pinion teeth  56  are at one end of the locking sleeve  54  and a plurality of locking sleeve grooves  58  are at the opposite end. The locking sleeve grooves  58  engage the first cam member tongues  38  as depicted in FIG.  6   a.  When the locking sleeve  54  and the first cam  36  are rotated counter-clockwise relative to the second cam  44 , the first and second cams  36 ,  44  are forced apart as depicted in  6   b.  The first cam  36  and the spring ring support  32  are restrained axially. Counter-clockwise rotation of the first cam  36  axially compresses the spring rings  34  between the second cam  44  and the spring ring support  32 . 
     As shown in FIG. 7, the locking sleeve  54  has a plurality of longitudinal locking sleeve slots  60  in its interior surface. The locking sleeve  54  is interposed between the protective shell  30  and the receiver forks  26 . In one embodiment, a plurality of locking sleeve teeth  62  are on the locking sleeve  54  interior surface between the locking sleeve slots  60 , and engage the receiver fork teeth  28 . 
     In FIG. 8, the assembled receiver  14  is uncocked. The locking sleeve slots  60  are partially aligned with the receiver forks  26  and are partially aligned with the space between the receiver forks. The receiver fork teeth  28  engage a portion of the locking sleeve teeth  62 . The remainder of each of the receiver fork teeth  28  extends into the locking sleeve slot  60 . In the uncocked position the first cam stop  40  rests against the second cam stop  48 . The portion of the locking sleeve teeth  62  not engaging the receiver fork teeth  28  extends into the space between adjacent receiver forks. 
     The assembled receiver  14  in FIG. 9 is in its cocked position. Rotation of the first cam  36  relative to the second cam  44  has forced the cams  36 ,  44  apart. The spring rings  34  are axially compressed. The spring rings  34  may only be axially compressed a predetermined distance. Once fully compressed, the exterior spring rings  34   a  abut adjacent exterior spring rings  34   a,  and interior spring rings  34   b  abut adjacent interior spring rings  34   b.  The full axial compression of the spring rings  34  creates a positive stop, preventing counter-clockwise rotation of the locking sleeve  54  past the cocked position. 
     In an alternative embodiment, a key and slot connection between the first cam  36  and the receiver body  18  (not shown) prevents counter-clockwise rotation of the locking sleeve  54  past the cocked position. 
     In the cocked position, the locking sleeve slots  60  are aligned with the gaps between the receiver forks  26 , and the locking sleeve teeth  62  fully engage the receiver fork teeth  28 . The receiver  14  is cocked by rotating the locking sleeve  54  counter-clockwise relative to the receiver body  18 . This is accomplished by applying counteracting torques to the receiver body pinion teeth  20  and the locking sleeve pinion teeth  56 . 
     When the assembled receiver  14  is in the cocked position, the stinger  12  may be inserted into the receiver  14 . The stinger forks  64  are inserted into the locking sleeve slots  60  and the space between adjacent receiver forks  26 . The stinger forks  64  are approximately as wide as the locking sleeve slots  60  and the space between adjacent receiver forks  26 . Once inserted, the stinger forks  64  abut adjacent receiver forks  26 . Stinger fork teeth  66  are on the stinger fork  64  exterior surfaces and are aligned with the receiver fork teeth  28 . 
     FIG. 10 is a cut away view of an assembled connector showing the stinger forks  64  adjacent the receiver forks  26 . 
     Once the stinger forks  64  are inserted into the locking sleeve slots  60 , the torque applied to the locking sleeve pinion teeth  56  and the receiver body pinion teeth  20  can be released. Upon release of the applied torque, the spring rings  34  axially decompress and force the first cam  36  to rotate clockwise relative to the receiver body  18 . Clockwise rotation of the first cam  36  rotates the connected locking sleeve  54  clockwise as well. As the locking sleeve  54  rotates, the locking sleeve teeth  62  engage the stinger fork teeth  66 . In the uncocked position, the locking sleeve teeth  66  engage a portion of the receiver fork teeth  28  and a portion of the stinger fork teeth  66 . 
     The embodiments described may be varied in many obvious ways. Such variations are not to be regarded as a departure from the spirit or scope of the invention. All such modifications are intended to be included within the scope of the following claims.