US3603110A

US3603110A - Well tools

Info

Publication number: US3603110A
Application number: US855309A
Authority: US
Inventors: John V Fredd
Original assignee: Otis Engineering Corp
Current assignee: Halliburton Co
Priority date: 1969-09-04
Filing date: 1969-09-04
Publication date: 1971-09-07
Anticipated expiration: 1988-09-07

Abstract

A coupler for interconnecting spaced bodies in an articulated manner. One form of the coupler includes elongate locking fingers having external locking bosses along opposite ends and supported by a spring in parallel spaced relationship along opposite sides of a pair of elongated spacers. The spacers are movable longitudinally against the spring toward either end of the coupler to allow the locking fingers along the other end of the coupler to be squeezed together for coupling into or uncoupling from a locking recess of one of the spaced bodies. Upon release the spring returns the spacers to neutral aligned positions holding the locking finger in parallel noncompressible coupling relationship. Another form of the coupler includes rotatable spaced latch rings around the locking fingers at opposite ends of the spring. The latch rings have internal release recesses and locking flanges and are each rotatable between a first position at which the spacers are released to move longitudinally relative to the ring and locking fingers and a second position at which the spacers are held against longitudinal movement at neutral positions between the locking fingers holding the locking fingers against compression in coupling positions. Both forms of the coupler are useful for interconnecting a plurality of well tools to form an articulated train of tools for movement through a tubing string.

Description

United States Patent [72] .Inventor John V. Fredd ABSTRACT: A coupler for interconnecting spaced bodies in Dallas, Tex. an articulated manner. One form of the coupler includes elon- [21] Appl. No. 855,309 gate locking fingers having external locking bosses along op- [22] Filed Sept. 4, 1969 posite ends and supported by a spring in parallel spaced rela- [45] Patented Sept. 7, 1971 tionship along opposite sides of a pair of elongated spacers. [73] Assignee Otis Engineering Corp. The spacers are movable longitudinally against the spring Dallas, Tex. toward either end of the coupler to allow the locking fingers along the other end of the coupler to he s ueezed to ether for q 2 coupling into or uncoupling from a locking recess of one of [54] WELL TOOLS the spaced bodies. Upon release the spring returns the spacers 17 Claims, 18 Drawing Figs. to neutral aligned positions holding the locking finger in paral- [52] U S I I M 64/16 lel noncompressible coupling relationship. Another form of [51] Fwd 3/44 the coupler includes'rotatable spaced latch rings around the [50] Fie'ld 0 64/16 locking fingers at opposite ends of the spring. The latch rings I 6 have internal release recesses and locking flanges and are each rotatable between a first position at which the spacers are 5 References i d released to move longitudinally relative to the ring and locking UNITED STATES PATENTS fingers and a second position at which the spacers are held against longitudinal movement at neutral positions between 3*096'679 7/l963 g 24/2 the locking fingers holding the locking fingers against com- 3507528 4/1970 Debmdrchm 287/124 pression in coupling positions. Both forms of the coupler are Primary Examiner-Mark M. Newman useful for interconnecting a plurality of well tools to form an Assistant Ixaminer-Randall Heald articulated train of tools for movement through a tubing Attorney-H. Mathews Garland string.

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' Ga l l f 73 y I l I I l l v 7 a I l 42 PATENTED SEP 71911 3.603110 sum 1 or 5 "Wm/r0)? John V. Fredd ATTORNEY PATENTEUSEP mm 31303110 SHEEI 2 0F 5 INVENTOR J0 h n V. F re d d ATTORNEY PATENTED SEP 7 l9?! SHEET t [1F 5 l/VVE/VTUR John V. Fredd BY ATTORNEY PATENT-E7085? nan 3503110 sum 5 or s nvvmron John V. Fre dd Arm/ms) WELL TOOLS This invention relates to well tools and more particularly relates to a coupler for connecting spaced bodies in an articulated manner.

It is a particularly important object of this invention to provide a new and improved coupler for pivotally interconnecting spaced well tools to provide an articulated well tool train which is movable through curved section of tubing.

It is another object of the invention to provide a new and improved coupler which resists accidental release. I

It is another object of the invention to provide a new and improved coupler which is releasably connectable at each of its opposite ends into a locking recess of a body.

It is another object of the invention to provide a coupler having locking fingers which do not require longitudinal movement for release and locking of the fingers thereby minimizing required end play between the coupler and bodies coupled therewith.

It is another object of the invention to provide a coupler of the character described including locking fingers having locking means at opposite ends thereof and which may remain in locked relationship in a locking recess of a body at one end while the locking fingers at the opposite end are compressed together for release of the coupler from a locking recess in a body.

It is still another object of the invention to provide a coupler of the character described which includes somewhat loosely fitting parts and having a flow passage therethrough leaving ample flow space in a flow conductor for fluid flow through the conductor past the coupler for performing various operational procedures in the handling of a tool train including one or more such couplers.

It is still a further object of the invention to provide a'coupler ofthe character described which is manually operable for coupling into and release from a locking recess of a body thereby eliminating the need for special tools in making up a tool train including one or more ofthe couplers.

It is a still further object of the invention to provide a coupler which is capable of transmitting torque between spaced bodies interconnected by the coupler so that the coupler is useful in self-orienting tool trains which require rotation to achieve a desired angular position in 21 HOW conductor.

It is a further object of the invention to provide a coupler of the character described which includes a pair of locking fingers supported along opposite sides of a pair of spacers by a spring biasing the fingers and spacers to a longitudinally aligned relationship holding the locking fingers parallel at coupling positions, and the spacers being longitudinally movable against the spring in either direction for releasing the other end portions of the locking fingers to be compressed together to uncoupling positions.

his a further object of the invention to provide a form of coupler which includes a pair of spaced rotatable latch rings disposed on the locking fingers and spaces and urged in opposite directions by the spring against flanges on the locking fingers. the latch rings having internal locking flanges and release recesses so that at one position of rotation of each of the latch rings it holds the spacers against longitudinal movement relative to the locking fingers while at another position of rotation the spacers are released for longitudinal movement relative to the locking fingers for compressing the locking fingers to uncoupling positions.

Additional objects and advantages of the invention will be readily apparent from reading the following description of a device constructed in accordance with the invention and by reference to the accompanying drawings thereof wherein:

FIG. 1 is a longitudinal side view in elevation of one form of coupler embodying the invention with its locking fingers and spacers aligned for holding the locking fingers at parallel locking positions and showing in cross section locking recesses in end portions of spaced bodies interconnected by the coupler;

FIG. 2 is an end view in elevation of the coupler of FIG. I removed from the interconnected spaced bodies;

FIG. 3 is a longitudinal side view in elevation showing the coupler of FIG. 1 with the spacers shifted longitudinally for uncoupling one end of the coupler from one of the interconnected spaced bodies;

FIG. 4 is an end view in elevation of the upper end of the coupler shown in FIG. 3 illustrating particularly the compressed positions of the fingers of the uncoupled end of the coupler;

FIG. 5 is a longitudinal outside view in elevation of one of the locking fingers of the coupler of FIG. 1 showing the surfaces of the locking finger viewed at to the view in FIG. 1;

FIG. 6 is a view in section of the locking finger along the line 66 of FIG. 5;

FIG. 7 is a longitudinal inside view in elevation of the locking finger of FIG. 5;

FIG. 8 is a longitudinal side edge view in elevation of one of the spacers of the coupler of FIG. 1 as seen at a 90 angle to the view shown in FIG. 1;

FIG. 9 is a longitudinal inside view in elevation of the spacer of FIG. 8 as seen at 90 to the right of the view shown in FIG.

FIG. 10 is a view in section of the spacer of FIGS. 8 and 9 as seen along the line 10--10 of FIG. 9;

FIG. 11 is a longitudinal view in section and elevation of another form of the coupler illustrating the coupling of spaced bodies by the coupler;

FIG. 12 is a longitudinal view in section and elevation of the coupler illustrated in FIG. 11 as viewed 90 to the right of the view presented in FIG. 1 1;

FIG. 13 is a longitudinal view in section and elevation of the coupler of FIGS. 11 and 12 illustrating the upper latch ring and the spring compressed downwardly with the spacers for compressing and uncoupling the upper end of the coupler;

FIG; 14 is a view in section along the line l4-14 of FIG. 1 1;

FIG. 15 is a view-in section along the line l5 15 of FIG. 11;

FIG. 16 is a view in section along the line 16-16 of FIG. 13;

FIG. 17 is a view in section along the line 17-17 of FIG. 13; and

FIG. 18 is an exploded perspective view of the parts of the coupler illustratedin FIGS. l1-l7.

Referring to FIG. 1 of the drawings, a coupler A embodying the invention is illustrated with its parts disposed at coupling positions interconnecting spaced bodies T and U which may comprise well tools in an articulated tool train movable in a flow conductor. For example, such a tool train is illustrated in FIGS. 1 and 3 of U.S. Pat. No. 3,419,074 issued to Norman F. Brown, Dec. 31, I968. The coupler A fulfills the function discharged by the couplers 260 shown and described in the Brown patent. Use of the coupler A as particularly discussed in the Brown patent and also in U.S. Pat. No. 3,428,346, issued Feb. 18, 1969 to John V. Fredd, facilitates the assembly of an articulated tool train which is particularly useful in remote well servicing operations especially in undersea, offshore wells where pump down procedures are employed and tool train capability of traversing curved flow conductor sections is essential to the well operations. Thus, for example, the spaced bodies T and U may comprise the piston unit 200 and the upper sleeve shifter of the down-shift assembly 300, as shown in FIG. 1 of the Brown patent.

The coupler A includes a pair of identical locking fingers 30 oppositely disposed along opposite sides of a pair of oppositely positioned identical spacers 31. The locking fingers and spacers are held together in operative relationship by a coil spring 32 which serves a dual function of holding the locking fingers and spacers together and biases them toward a neutral, longitudinally aligned, coupling relationship, as illustrated in FIG. 1. The spacers are movable toward either end of the coupler to a position represented in FIG. 3 at which end portions of the locking fingers at the other end of the coupler are compressed together for coupling and uncoupling such end of the coupler.

Each of the locking fingers has the general shape of a longitudinal cylindrical segment as evident from FIGS. 2, 4, and 6. The central body portion 33 of each locking finger is substantially a longitudinal half-cylinder section, FIG. 6, extending between a shoulder surface 34 on an externalboss 35 near one end of the locking finger and an identical shoulder surface 34a on an identical boss 35a near the other end of the locking finger. The upper end portion of the locking fingers 30, as shown in FIG. 1, above are provided with a locking recess defined by an upwardly and inwardly tapered surface portion 41 on the boss 35, a cylindrical recess bottom surface portion 42 and a surface portion 43 on a locking boss or flange 44 of the locking finger tapered toward the center of the finger. The locking boss 44 has an upwardly and inwardly tapered surface 45. The opposite lower end portion of the locking finger is identical with its various surface portions referred to by the same reference numerals with the subscript a added. The locking finger has parallel flat opposite longitudinal side surfaces and an internal longitudinal cylindrical surface portion 52 running the length of the finger between chamfered outwardly sloping end surfaces 53 and 53a. The locking finger is provided internally along opposite sides of the cylindrical surface 52 with identical locking surfaces 54 and 54a disposed along opposite end portions of the locking finger at opposite ends of a flat relieved inside surface 55 extending between sloping cam surfaces and 60a. The inside surfaces 60 and 60a with the relieved surfaces 55 define an internal recess 61 along each inside edge surface along'opposite sides of the cylindrical surface 52 of each locking finger for receiving an end portion of the associated spacer when the spacers are misaligned longitudinally for locking and releasing the coupler as in FIG. 3. Each of the locking fingers has identical end surfaces 62 and 62a which lie in planes perpendicular to the longitudinal axis of the finger.

Each of the spacers 31 has a central cylindrical segment portion 69 having spaced

spring retainer flanges

70 and 70a provided with

shoulders

71 and 71a, respectively. The central portion 69 and the spring retainer flanges are formed integral with an elongate, generally rectangular, bar 72 having locking end portions 73 and 73a. The bar has identical tapered opposite ends 74 and 74a which may perform a camming function as discussed later in spreading the locking fingers from uncoupling to coupling positions. The end portion 73 of the bar has opposite side locking surfaces 75 while the other end portion of the bar has identical parallel locking surfaces 750, each pair of end locking side surfaces being positionable between adjacent end portions ofthe locking fingers for holding the fingers outwardly at their locked coupling positions. The spacer has flat internal-surfaces 80, FIG. 9, disposed on opposite sides of the bar 72 which engage and slide along the side surfaces 50 the locking fingers along each side of the coupler.

The locking fingers 30, spacers 31, and the spring 32 of the coupler A are assembled in the relationship shown in FIGS. 1 and 2. The two locking fingers are held in parallel spaced relationship with their inner surfaces 52 facing each other and the internal locking surfaces 54 and 54a of the two locking fingers laterally and longitudinally aligned. The pair of spacers 31 are disposed along the side surfaces 50 of the locking fingers as shown in FIG. 2. The opposite end portions 73 and 73a of the spacer bar on each of the spacers are aligned between the facing locking surfaces 54 and 54a, respectively, of the locking fingers so that the locking fingers are spaced apart in substantially parallel relationship at which position they are held by the spacers so long as the spacers remain centrally longitudinally aligned with the locking fingers. The spring 32 is assembled around the locking fingers and spacers with the opposite ends of the spring being confined between the shoulder surfaces 34 and 34a of the locking fingers and 71 and 71a of the spacers. The spring holds the locking fingers and spacers together in the relationship illustrated and so long as no force is applied to either the spacers or the fingers to longitudinally displace them from each other, the spring holds them in the longitudinal alignment of FIG. 1 with the shoulder surfaces 71 and 71a on the spacers being generally in alignment with the shoulder surfaces 34 and 34a, respectively, on the locking fingers. With the end portions of the spacer bars at the opposite ends of the spacers being disposed between adjacent locking finger locking surfaces the locking fingers cannot be compressed toge ther at either end. i

FIG. 3 illustrates the shifted positions of the spacers and spring of the coupler and compression of the end portions of the locking finger for either coupling or uncoupling either end of the coupler. For example, assuming that the upper end of the coupler is to be connected with the well tool, the spacers 31 are both grasped by their flanges 70 and forced downwardly against the spring 32 compressing the spring and moving the spacers downwardly relative to the locking fingers. The spacers slide along the finger side surface 50. The spacers are readily moved downwardly by grasping the flanges 71 with the thumb and forefinger of one hand of the operator while generally grasping the locking fingers in the other hand in such a manner that the spacers may be forced downwardly relative to the locking fingers. The spacers are both forced downwardly at the same time as they both must be moved simultaneously and in alignment with each other for the functioning of the coupler. As the spacers move downwardly the lower end portions 73a of the spacer bars are inserted farther into the space between the locking surfaces 54a along the lower end portions of the locking fingers while the upper spacer bar end portions 73 are withdrawn downwardly from between the upper locking surfaces 54 of the locking fingers. When the tapered upper ends 74 of the spacers are below the locking finger surfaces 60, the upper end portions of the locking fingers are squeezed together to the contacting relationship shown in FIG. 3 at which the upper ends of the adjacent locking surfaces 54 along the inside edges of the fingers are in engagement with each other. The recesses 61 along the locking finger inside edges provide clearance space for the spacer end portion 73 to allow the upper ends of the locking fingers to come together. The distance between the locking finger flange surfaces 44 and thus the effective diameter of the upper end of the coupler is substantially reduced as evident in FIGS. 3 and 4 so that the upper end portions of the locking fingers may be inserted into the locking recess of the well tool T past its locking flange 91. It will be seen that when the upper end portions of the locking fingers are brought together into contact, the lower ends of the fingers which are illustrated in FIG. 3 within the locking recess of the lower tool U are spread very slightly apart due to the lever action of the fingers about their points-of contact with the lower spacer bar portions 731; of the spacers. It will also be observed that the locking fingers remain in longitudinal alignment with each other, and since they are not displaced longitudinally from each other and their lower ends are only slightly affected by the compression of their upper ends, the coupling relationship of the lower end of the coupler. with the tool U is not affected by the manipulation of the upper end when coupling or uncoupling it.

The compressed end portion of the coupler is inserted into the locking recess 90 until the locking flange surfaces 43 on the locking fingers are past the locking flange 91 of the tool. The spacers are then released allowing the spring to expand with the upper end of the spring bearing against the spacer shoulder surfaces 71 lifting the spacers relative to the locking fingers. The tapered upper ends 74 of the spacer bars engage the internal cam surfaces 60 of the locking fingers spreading the upper end portions of the fingers apart until they are spaced to receive the upper end portions 73 of the spacer bars. The spring lifts the spacers back to the aligned position shown in FIG. 1 so that the locking fingers are returned to their substantially parallel coupling relationship at which neither end of the coupler can be compressed due to the presence of the end portions of the spacer bars between the internal locking surfaces of the locking fingers at both ends of the coupler. The locking finger surfaces 44 with the spacer between and holding the finger end portions apart cannot be compressed together sufficiently to clear the locking flange 91 at the mouth of the locking recess 90 in the tool T so that the upper end portion of the coupler is locked with the tool as shown in FIG. 1. Similarly, the lower end of the coupler is coupled with the tool U by insertion of the lower end portions of the locking fingers into the locking recess 92. The spacers of the coupler are lifted upwardly against the spring 32 compressing the spring with the spacer flanges 70a until the lower end portions 73a of the spacer bars are withdrawn from between the locking surfaces 54a along the lower end portions of the locking fingers so that the lower locking finger end portions are compressed together allowing the locking flanges on the fingers to be inserted into the locking recess of the tool.

When the tools T and U are coupled as shown in FIG. 1 by the coupler A substantial forces may be applied either intension or compression between the tools T and U and the tools may be bent or pivoted substantially relative to each other while remaining connected together by the coupler and without any tendency to accidentally disengage the coupler from either of the tools. The only way in which the coupler is disengageable from either of the locking recesses of the tools is by longitudinal movement of the pair of spacers to either of their end positions so that the locking fingers of the coupler may be fully compressed together at the opposite end of the coupler. Since only the spacers need be displaced longitudinally for coupling or uncoupling the coupler, the locking fingers themselves remain in longitudinal alignment so that only minimum length locking recesses, such as the

recesses

90 and 92 in the tools T and U, are required to accommodate the locking flange portions of the locking fingers of the coupler. Either end of the coupler may be manipulated for coupling or uncoupling without disturbing the relationship at the other end of the coupler. When the coupler is connected between tools such as T and U in FIG. 1, either tension or compressive forces between the tools only serve to squeeze the coupler finger end portions more tightly against the intervening end portions of the spacers. For example, in FIG. 1, a force tending to lift the tool T relative to tool U urges the tapered locking boss surface portions 43a of the locking fingers against the tapered surface 93a of the flange 93 on the tool U camming the locking fingers toward each other more tightly engaging the inner locking surfaces 540 of the fingers against the side surfaces 75a of the spacers, the spacers preventing the fingers from being squeezed together sufficientlyto withdraw the coupler from the locking recess of the tool U. The same action, of course, occurs at the upper end of the coupler with the locking flange 91 of the tool T. Similarly, a compressive force tending to push the tool T downwardly toward the tool U forces the downwardly and inwardly tapered surfaces 41a on the coupler locking fingers against the upper end of the tool U also camming the locking finger end portions inwardly more tightly against the spacer end portions 730. The central flow passage 95 along the longitudinal centerline of the coupler defined by the locking fingers and spacer as evident in FIG. 2 allows free flow of fluid through the coupler so that if fluid is pumped along the tool string and the tools T and U are designed to conduct a stream of fluid, the stream may readily pass along the tool train through the coupler. The coupler is simple, strong, and includes no parts which are secured by threads or other similar forms of connection which are likely to become disengaged during the use of the coupler under severe downhole operating conditions. The coupler may be manually quickly coupled and released at either of its ends.

Another form of coupler B embodying the invention is illustrated in FIGS. 11-18. The coupler B consists of a pair of identical locking fingers 100 supported in longitudinal opposed relationship along opposite edges of a pair of elongate oppositely disposed spacers 101. The locking fingers and spacers are held together by a coil spring 102 which bears at its opposite ends against identical split latch rings 103 encircling the locking fingers and spacers and each rotatable between a position for locking the spacers against movement relative to the locking fingers and a position for releasing the spacers for movement relative to the locking fingers.

Each of the locking fingers includes an elongate body 104 in the form of a longitudinal cylindrical segment having identical external integral spaced arcuate flanges 105 and 105a. The flanges 105 and 105a have facing shoulder surfaces and 110a, respectively, which lie in planes perpendicular to the longitudinal axis of the finger and which function as end stops for the latch rings 103 and 103a. Each of the flanges 105 and 105a has parallel side edges designated by the reference numeral 111 on the

flange

105 and 111a on the flange 1050. The opposite ends of the locking finger body 104 are provided with the external locking bosses 112 and 112a which are spaced on the body from the flanges 105 and 105a, respectively. The locking boss 112 is defined by a spherical surface portion 113 facing the flange 105 and joining a cylindrical surface portion 114 having an axis common with the axis of the locking finger body andan end spherical surface portion 115. The locking boss 112 has an open ended longitudinal slot which extends radially through the entire thickness of the locking boss end of the finger and is extended symmetrically along the longitudinal axis of the finger extending longitudinally in the finger into the spherical surface 113. The locking boss also has parallel side edge surface portions 121 which lie in the same planes as the side surfaces 111 and 1 11a on the

flanges

105 and 1050. The locking boss 112a along the other end of the locking finger has identical surface features and other characteristics as the locking boss 112 and which are referred to by the same reference numerals with the suffix a added. The inner side of the locking fingers has a cylindrical internal surface portion between longitudinal spaced inside edges 131 which extend between cam surfaces 132 and 132a which slope inwardly toward the opposite ends of the locking finger. The locking fingers have inside locking surface edge portions 133 along the inner face of the locking boss 112 and 133a along the inner face of the locking boss 1120. The locking surfaces 133 and 1330 all lie in a common plane which is parallel to and displaced inwardly from the plane of the inside edge surfaces 131. The longitudinal surfaces 131 with the sloping cam surface 132 and 132a define an internal longitudinal recess along each longitudinal inside edge of each of the locking fingers to provide space to receive portions of the spacers 101 between the locking fingers when the spacers are shifted longitudinally out of alignment with the finger-locking surfaces at either end of the coupler to allow the coupler fingers to be squeezed together at that end for coupling and uncoupling. The combined space between the oppositely positioned fingers provided by the recesses along adjacent inside edges of the fingers each accommodate the necessary portion of the spacer between such adjacent edges for'the fingers to be fully compressed together at either end of the coupler when the spacers are shifted toward the other end of the coupler.

The spacers 101 each comprise an elongate rectangular spacer bar formed integral with identical longitudinal flange end portions 141 and 141a spaced on opposite ends of a central flange portion 142. The spacing between the

flange portions

141 and 142 defines a latch ring slot 143 for the latch ring 103 and the spacing between the flange portions 141a and 142 defines an identical latch ring slot 143a for the latch ring 103a. As particularly evident in the left spacer 101 of FIG. 18, the lateral opposite ends of the

slots

143 and 143a are outwardly divergent thereby eliminating abrupt corner edges to provide for smoother rotation of the latch rings between their spacer latching and spacer releasing positions. The inner faces of the

flange portions

141 and 1410 and 142 of the spacers provide bearing surface portions as designated by the reference numeral 144 along the right spacer in FIG. 18 which bearing surfaces are perpendicular to the adjacent side edges 145 of the spacer bar 140 so that the spacers readily slide along the side edge surfaces of the locking fingers. For example, the inside flange surfaces 144 along one side of each spacer engage and slide along the side face surfaces 111, 1

11a

121, and 1210 of one of the locking finger while the surfaces 144 along the other side of the spacer engage and slide along the corresponding surfaces of the other locking finger. The opposite ends of the spacers have tapered surfaces at and 1500 which facilitate smooth longitudinal movement of the spacers and provide cam surfaces which coact with the internal cam surfaces 132 and 132a of the fingers for spreading the fingers when returning the spacers toward an end of the coupler to shift the locking bosses at that end of the coupler from their compressed back to their coupling positions. For example, the tapered surfaces 150 at the upper ends of the spacers in FIGS. 13 and 18 engage the cam surfaces 132 along the inside edges of the locking fingers on opposite sides of the spacers forcing the locking finger ends apart to return them from compressed to spaced apart coupling positions.

The split latch ring 103 is counterbored at 160 providing an internal shoulder surface 161 so that the upper end portion of the spring 102 as viewed in FIG. 18 is received within the latch ring with the upper end of the spring bearing against the shoulder surface 161 within the latch ring. The upper face of the latch ring 103 is counterbored at 162 on a diameter slightly larger than the effective diameter between the outside cylindrical surface portions of the opposed spacers as seen in FIG. 17. By such proportioning of the counterbore 162, the lower ends of the spacer flange portions 141 are received within the counterbore 162 when the latch ring 103 is oriented in the position shown in FIG. 18 in the assembled relationship of the coupler parts as represented in FIGS. 11 and 12. The counterbores provide an internal annular flange 163 which is received in the slots 143 of the spacers when the latch ring oriented in the position of rotation represented in FIG. 18 thereby holding the spacers against movement relative to the latch ring. The latch ring is slotted or split at 164 and has a recess 165 on the opposite side of the ring 180 from the slot 164 extending through the thickness of the ring longitudinally in its internal annular flange 163. The depth of the recess 165 measured radially of the ring is sufficient that in the assembled relationship of the parts when the ring is aligned with the spacer as in FIG. 17, the spacer flange section 142 may move longitudinally through the ring. Similarly, the slot 164 allows the front spacer to move through the ring along the locking fingers. The position of the latch .ring in FIG. 17 is 90 removed from the position of the ring represented in FIG. 18. The top or outside face of the latch ring 103 in its position in FIG. 18 has a transverse key slot defined by the top face recesses 170 and 171 on opposite sides of the top face of the ring symmetrical with the slot 164 and the recess 165, respectively. The key slot defined by the

recesses

170 and 171 functions to lock the latch ring against rotation when the ring is oriented as in FIG. 18. The locking finger flange 105 of the righthand finger rests in the recess 171 while similarly the flange 105 on the left-hand locking finger extends within the recess 170 on the opposite side of the latch ring. The flange surface 110 on the right-hand finger flange 105 rests against the top face of the latch ring 103 within the recess 172 so that the edge surfaces 173 on each side of the recess engage the side edges 111 of the locking finger flange 105 precluding rotation of the latch ring relative to the locking finger. Identically, on the other side of the ring the recess edges 171 engage the side faces 1 11 of the flange 105 of the other locking finger. The inner bore of the latch ring, that is the opening through its internal flange portion 163, is of a diameter slightly larger than the diameter of the circle defined by the oppositely positioned locking fingers along the outside surface oftheir body portions 104 between the flanges 105 and 105a as evident in FIG. so that the latch ring is free to move longitudinally along the central body portions of the locking fingers in their assembled relationship for shifting the latch rings and the spacers between the positions required for coupling and uncoupling either end of the coupler. The other latch ring 103a is identical to the latch ring 103 with its various features referred to by the same reference numerals with the suffix a added.

The coupler B is useful in the same manner as the coupler A for interconnecting well tools such as the tools X and Y represented FIGS. 11-13 to form a tool train for movement in a flow conductor. The coupler B is especially useful under conditions where it is desired to orient the tool train at a par ticular position of rotation in a flow conductor and transmission of torque between the tools X and Y is required to keep the tools X and Y in the same relative radial positions with respect to each other as tool train is rotated in the flow conductor.

The tool X is provided with an open ended locking recess 180 opening through the end of the tool body through an internal annular locking flange 181. A pair of diametrically opposed lock pins 182 are press fitted along their outer end portions through the tool housing inwardly of its locking flange 181 with the inward end portions 183 of the lock pins projecting into the locking recess 180. Similarly, the lower tool Y has an open ended locking recess 184 opening into the upper end of the tool through a locking flange 185. A pair of diametrically opposed lock pins 190 are press fitted through the wall of the tool housing into the locking recess 184 with the inward end portions 191 of the pins projecting into the locking recess. FIGS. 11 and 12 show the coupler B interconnecting the tools X and Y with the lock pins 182 of the tool X received within the slots in the locking fingers of the coupler and the inward end portion 191 of the lock pins 190 in the tool Y received within the slots 120:: at the lower end of the coupler locking fingers. Thus, torque is transmittable from the tool X through its pins 182 to the coupler to rotate the coupler or hold it relative to the tool X, while similarly the coupler is held against rotation relative to the tool Y by the interconnection between the lock pins 190 and the coupler. The tools X and Y and the coupler B remain at the same positions of rotation so long as they are interconnected as viewed in FIGS. 11 and 12. FIG. 13 represents the coupling or uncoupling of the upper end of the coupler with the tool X.

Referring to FIGS. 11 and 12, in the assembled relationship of the parts of the coupler B, the locking fingers 100 are parallel and in longitudinal alignment with each other with inside surfaces including the cylindrical surfaces and the flat edge surfaces 131 and 133 and 133a facing each other in substantially parallel spaced relationship. Along the opposite longitudinal sides of the locking fingers the spacers 101 are disposed in parallel relationship to each other with their spacer bars extending between the

inside edges

131, 133, and 133a of the locking fingers. At the neutral coupling positions of the parts represented in FIGS. 11 and 12, the locking surfaces 133 and 133a of one of the locking fingers of the coupler engage opposite end portions of the some side edges of the spacer bars 140, while the locking surfaces 133 and 133a of the other locking finger engage opposite end portions of the other side edges 145 of the spacers so that the locking fingers are held along their entire lengths by the spacer bars in parallel spaced relationship with each other and with the spacer bar portions interposed between the locking fingers. The locking fingers cannot be compressed inwardly at either end from the parallel spaced positions at which they are held by the spacer bars, such relationship being particularly evident in FIG. 1 1.

The latch rings 103 and 103a are assembled around the central portions of the locking finger bodies 104 and the flange sections 142 of the spacers. The rings are urged to their longitudinally spaced end positions against the flanges 105 and 105a by the spring 102. The upper end of the spring 102 is received within the counterbore of the latch ring 103 with the upper end of the spring bearing against the internal flange surface 161 of the ring urging the ring upwardly against shoulder surfaces 110 of the flanges 105 on the locking fingers. The latch ring 103 is aligned as represented in FIG. 18 and FIG. 11 so that the flange 105 of the right-hand locking finger in the drawings is received in the recess portion 172 of the key slot across the top surface of the latch ring, and similarly, the flange 105 of the left-hand locking finger fits in the key slot recess portion 170 of the latch ring whereby the latch ring cannot rotate relative to the locking fingers. The portions of the flange 163 on the opposite sides of the slot 164 and recess 165 pass through the spacer recesses 143 of the spacers 101 holding the spacer against movement relative to the latch ring. Thus, with the latch ring 103 bearing against the upper flange faces 110 of the locking finger flanges 105 and the spacers held by the latch ring flange 163 against movement, the spacers cannot move upwardly beyond the position illustrated in FIG. 11. The lower latch ring 103a is urged by the lower end of the spring 102 against the flange faces 110a of the flanges 1050. The lower end of the spring bears against the flange surface 161 within the lower latch ring. The lower latch ring fits partially over the flanges 105a with the flange 1050 on the right-hand locking finger being received in the key slot portion 170 in the bottom face of the latch ring and the flange 105a on the left-hand locking finger being received in the key slot portion 172 in the bottom face of the latch ring so that the lower latch ring also is not rotatable relative to the locking fingers. The flange portions 1630 in the lower latch ring extend through the recesses 143a of the spacers thereby precluding relative movement between the spacers and the lower latch ring. The lower face of the lower latch ring is engaged with the shoulder surfaces 110a of the lower locking finger flanges 105a and thus the spacers cannot move downwardly relative to the locking fingers. With the spacers being held against upward movement by engagement with the upper latch ring 103 and against downward movement by the lower latch ring 103a and the opposite end portions of the spacer bar 140 of each spacer disposed between the locking surfaces 133 within the upper ends of the locking fingers and the locking surfaces 133a within the lower ends of the locking fingers, the locking fingers are held in parallel spaced relationship and cannot be pressed inwardly at either end.

Thus, with the coupler connected with the tools X and Y, FIGS. 11 and 12, and the spacer bars locked against longitudinal movement preventing compression of either end of the coupler fingers, the coupler provides a pivotal connection with each of the well tools. The locking bosses 112 at the upper end of the coupler have an effective diameter larger than the internal diameter of the opening through the locking flange 181 in the upper well tool so that the locking flanges are confined within the locking recess 180 of the tool X. Similarly, the lower locking bosses 112a are confined within the lower locking recess 184 of the lower tool Y. The

pins

182 and 190 prevent rotation of the coupler relative to the tools X and Y, respectively, while permitting pivotal movement between the coupler and the respective tools. For example, the pins 182 are received within the slots 120 at the upper end of the coupler along a line coincident with the pivot point of the upper end of the coupler within the tool locking recess so that pivotal movement in any direction is permitted between the coupler and the tool. The elongated slots 120 allow the coupler axis to change relative to the axis of the locking pins 182 within the limits permitted by the space between the body portionsof the locking fingers and the opening through the locking flange 181 around the locking recess 180 in addition to the coupler pivoting on the axis of the pins providing a torque transmitting universal joint between each end of the coupler and the tools connected to it. The compressive or ten sion forces on either end of the coupler simply tends to urge the coupler finger end portions more tightly against the intervening spacer bars which are holding them in their parallel coupling relationship.

By manipulation ofthe latch rings 103 and 103a the spacers 101 may be released for movement in either direction relative to the locking fingers so that the locking fingers at the other end of the coupler may be squeezed together for coupling and uncoupling. Compression of the locking fingers along the upper end of the coupler is shown in FIG. 13 to permit the upper end of the coupler to be inserted into or withdrawn from the locking recess 180 of the tool X. To shift the coupler from the relationship shown in FIG. 11 to that of FIG. 13 so that the locking bosses 112 at the upper end of the coupler may be squeezed together, the latch ring 103a is revolved 90 in a clockwise direction as viewed from above the coupler so that it is shifted to the position represented in FIG. 17. The latch ring 1030 is released for rotation by lifting it a short distance against the spring 102 until the upper portions of the locking finger flanges 105a are withdrawn from the lower face

key slot recesses

170 and 172 of the latch ring. When the lower latch ring is free to turn, it is manually revolved 90 to the position shown in FIGS. 17 and 13 with the slots 164a and the recess 165a being aligned with the oppositely disposed spacers 101 and the latch ring flange sections 163 being revolved out of alignment with the spacer slots 143a so that the spacers are not held against movement relative to the lower latch ring. The latch ring slot 164a and recess 165a provide space in the ring 103a to allow the spacers to move longitudinally relative to the latch ring. The upper latch ring 103 remains engaged with the spacers by its flange portions 163 disposed through the upper spacer slots 143 so that the upper latch ring is forced downwardly against the spring with the latch ring flange sections 163 engaging the top end edges of the central spacer flange portions 142 forcing both of the spacers downwardly relative to the locking fingers. The upper latch ring is moved downwardly until it is at substantially the position shown in FIG. 13 at which the upper ends 150 of the spacers are below the upper internal locking surfaces 133 of the locking finger. The lower ends of the spacers simply move farther downwardly between the lower locking finger surfaces 1330 as illustrated. When the upper ends of the spacers move below the cam surfaces 132, the upper ends of the locking fingers along the bosses 112 are free to be compressed inwardly together as shown in FIG. 13. The upper ends of the locking surfaces 133 of both of the locking fingers are brought together thereby reducing the effective diameter of the upper end portion of the coupler along the locking bosses 112 to less than the diameter of the retainer flange 181 of the locking recess 180 of the tool X so that the upper end of the coupler may be introduced into or removed from the tool-locking recess. In introducing it into the recess, the slots of the locking fingers are aligned with the pins 182 so that when the coupler is inserted into the recess, the pin portions 183 are received in the slots 120. In coupling the fingers into the locking recess, the boss portions 112 are inserted until the spherical surface portion 113 on the fingers is above the locking flange 181. The upper latch ring 103 is then released allowing the spring 102 to expand forcing the latch ring upwardly with its flange portions 163 engaging the lower ends of the flange portion 141 on the spacers lifting the spacers upwardly relative to the fingers. The tapered upper ends of the spacers engage the cam surfaces 132 within the locking bosses of the locking fingers camming the fingers back apart until they are sufficiently spaced to receive the bar portions of the spacers between the locking surfaces 133 within the upper ends of the locking fingers. The latch ring and the spacers are lifted by the spring until the upper face of the latch ring engages the lower faces 110 on the locking finger flanges 105 with the flanges 105 being again received within the

key slot portions

170 and 172 of the ring holding the latch ring against rotation relative to the locking fingers and limiting further upward movement of the spacers. The lower latch ring 1030 is rotated back 90 until its key slot recess portions 170a and 172a are again aligned with and receive the locking finger flanges 105a thus returning the lower latch ring to its locked position and holding the spacers against downward movement relative to the locking fingers.

When coupling or uncoupling of the lower end of the coupler is desired, the upper latch ring 103 is rotated 90 to align its slot 164 and recess with the spacers thereby releasing the spacers for upward movement relative to the locking fingers. The lower latch ring is lifted against the spring 102 lifting the spacers from between the lower locking surfaces 133a of the locking fingers until the lower end 1500 of the spacers are above the cam surfaces 132a within the locking fingers so that the lower ends of the locking fingers are compressible together until the surfaces 133a of the fingers engage each other reducing the effective diameter of the lower end of the couplersufficiently to permit its insertion into or withdrawal from the locking recess 184 of the lower tool Y. Once the locking fingers in their parallel coupling relationship. The

upper latch ring is rotated 90 back to a locked position on the locking fingers.

While the rotation of the latch rings has been described in terms of a particular direction and the orientation of the rings has been illustrated with the slot 164 of the upper ring facing in one direction and the slot 164a of the lower ring facing in the opposite direction when the spacers are locked against movement in either direction, it is to be understood that the functional symmetry of the latch rings permits them .to be either aligned with each other or opposite to each other without affecting the operation of the coupler. ln shifting the latch rings through 90 rotation for moving them from either a release or a latch position to the opposite position, they may be moved in either direction 90.

As with the coupler A, the coupler B is manipulated between coupling and uncoupling conditions by movement of only its spacers 101 without affecting the longitudinal aligned relationship of its locking fingers 100 so that only minimum tolerance is required in the locking recesses of the tools with which the coupler is connected. The latch rings are readily manipulated by hand thereby eliminating the need for special tools for operation of the coupler. The locking feature of the latch rings whereby they are held against rotation relative to the locking fingers when the fingers are in their coupling position minimizes any tendency toward accidental release of the coupler. The location of the latch rings between the flanges of the locking fingers sufficiently removes them from the end portions of the coupler to prevent accidental contact between the rings and whatever tool is connected with the coupler so that only positive longitudinal and rotational movement of the latch rings allows the coupler to be operated for either coupling or uncoupling at either end. Complete assembly and disassembly of the coupler is readily effected by the use of the split latch rings permitting them to be assembled on and removed from the locking fingers and couplers utilizing the slots 164 and 164a in the latch rings. In both assembly and disassembly of the coupler, the latch rings may be aligned with each other with their slots and recesses 164, 165, 164a, and 165a being aligned with the spacers so that the spacers may slide into position through the latch rings along side the edges of the locking fingers from either end of the aligned locking fingers. Assembly and disassembly may be accomplished generally without special tools and at most a simple tool such as a screwdriver is required.

It will be seen that the coupler B provides means for connecting a train of spaced bodies such as well tools in an articulated manner giving maximum flexibility and thus capability of traversing curved sections of flow conductors; it may be connected at either end without affecting the opposite end of the coupler; and it may be utilized where transmission of torque between connected tools is desired for orientation and similar purposes.

Theforegoing description of the invention is explanatory only and changes and details of the construction illustrated may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent IS.

1. A coupler for interconnection of spaced bodies comprising: a plurality of locking members supported together for movement along opposite end portions between locking and release positions; and spacer means disposed for movement between a first position for holding said locking members in locking positions and other positions for releasing said locking members for movement to nonlocking positions along one end portion of said coupler while retaining said locking members in locking positions along an opposite end portion of said coupler.

2. A coupler in accordance with claim I wherein said locking members have locking surfaces engageable by said spacer means for holding said locking members in spaced locking relation at said first position of said spacer means when said spacer means is disposed between said locking surfaces and said locking surfaces being coengageable at one end of said coupler upon movement of said spacer means to one of said other positions at which said spacer means is removed from between said locking surfaces at said end of said coupler.

3. A coupler as defined in claim 2 wherein said locking members comprise locking fingers longitudinally aligned with each other at both locking and unlocking relationships and said spacer means comprises means longitudinally movable along said locking fingers between said locking surfaces on said locking fingers between said first position at which said spacer is disposed between said locking surfaces of said locking fingers along opposite end portions of said coupler and said other positions at which said spacer member is spaced longitudinally from said locking surfaces at one end of said coupler to release said locking fingers along said end of said coupler for movement toward each other to a nonlocking relationship.

4. A coupler in accordance with claim 3 including spring means associated with said locking fingers and said spacer means biasing said spacer means toward said one position for holding said locking members in locking relationship and compressible for movement of said spacer means to said other positions.

5. A coupler in accordance with claim 4 including latch means operatively associated with said spacer means and movable between a first position for holding said spacer means against movement relative to said locking fingers and a second position for releasing said spacer means for movement relative to said locking fingers.

6. A coupler for interconnecting spaced bodies comprising: elongate locking fingers supported in longitudinal alignment spaced for lateral movement at each end thereof between a first spaced locking relationship and a second engaging release relationship; and an elongate spacer disposed between said locking members and movable between a.first central position holding said fingers at each end of said coupler at said first spaced locking relationship and end positions toward either end of said locking fingers for releasing said fingers for movement toward each other at the other end of said fingers while holding said fingers in spaced locking relationship at the end toward which said spacer is moved.

7. A coupler in accordance with claim 6 including spring means associated with said locking fingers and said spacer biasing said spacer toward said first position.

8. Acoupler in accordance with claim 7 including latch ring means operatively associated with said spacer for holding said spacer at said first position at one position of rotation of said latch ring and being rotatable to a second position of rotation for releasing said spacer for longitudinal movement to said end position.

9. A coupler in accordance with claim 8 wherein said latch ring means comprises a first latch ring for locking said spacer against movement toward a first end of said locking fingers and a second latch ring for locking said spacer against movement toward a second end of said locking fingers, said latch rings being engageable with said spring and biased in opposite directions by said spring.

10. A coupler for interconnection of spaced bodies comprising: a pair of elongate locking fingers supported in substantially longitudinal alignment with each other, said locking fingers each having external locking bosses along opposite end portions thereof and a pair of external spring retainer flanges spaced from each other and spaced from said locking bosses, said locking fingers being further provided with inside locking surfaces along the opposite ends thereof, said locking surfaces at corresponding ends of said locking fingers being disposed in parallel spaced relationship when maintaining said locking bosses in locking relationship and movable toward each other to position the locking bosses along said ends in nonlocking released relationship; a pair of elongate spacers oppositely disposed from each other and along opposite sides of said locking fingers for longitudinal movement relative to said locking fingers from a central position at which end portions of said spacers are disposed between said locking surfaces of said locking fingers at both ends of said coupler holding said locking finger end portions and the locking bosses thereon in substantially parallel spaced locking relationship and said spacers being movable toward either end of said coupler withdrawing the other ends of said spacers from between the locking finger locking surfaces at the other end of said coupler thereby releasing said fingers for movement toward each other along such other end of said coupler to an uncoupling relationship of said locking bosses at said end of said coupler; a spring disposed around said locking fingers and said spacers between said spring retainer flanges on said locking fingers; and means associated with said spacers interconnecting said spacers and said spring biasing said spacers to said central position relative to said locking fingers for holding both ends of said locking fingers in parallel spaced locking relationship.

1 l. A coupler in accordance with claim wherein each of said spacers has spaced external spring retainer flanges positioned on said spacers in alignment with said spring retainer flanges on said locking fingers when said spacers are centrally disposed along said locking fingers, said spring being confined between said spacer flanges.

12. A coupler in accordance with claim 10 including a pair of latch rings disposed around said locking fingers and spacers and spaced on said fingers and spacers at opposite ends of and engaged with said spring, one of said latch rings being biased toward the spring'flanges on said locking fingers toward one end of said locking fingers and the other of said latch rings being biased toward the spring flanges toward the other end of said locking fingers, each of said latch rings being rotatable between a first locking position for holding said spacers against movement in the direction of the end of said locking fingers adjacent to said latch ring and movable to a second position of rotation for releasing said spacers for movement toward said adjacent end of said locking fingers.

l3.'A coupler in accordance with claim 12 wherein each of the said latch rings has a laterally extending key slot defining recesses toward each side of each latch ring on the side of said ring facing the spring flanges on the locking fingers toward which said ring is biased, said key slot being adapted to receive said spring flanges at said first position of each of said latch rings for releasably locking each of said latch rings against rotation relative to said locking fingers and spacers, said latch rings having internal recesses toward opposite sides of said rings extending in a direction of the axis of each of said rings for receiving said spacers whereby said spacers are released for movement relative to each of said rings when each of said rings is rotated to said second position, each of said rings having internal locking flanges, and each of said spacers having locking recesses for receiving one of said locking flanges in said latch rings for holding said spacers against movement relative to said latch rings when said latch rings are at said first positions of rotation on said coupler.

14. A coupler in accordance with claim 13 wherein each of said locking fingers has a longitudinal slot opening through the locking boss at each end of said finger for receiving a pin supported from the spaced body with which said end of said coupler is connected whereby torque is transmitted between said coupler and said spaced body while said coupler is pivotally connected with said spaced body.

15. A coupler in accordance with claim 10 wherein each of said locking fingers has internal longitudinally extending recesses for receiving an end portion of said spacers when said spacers are moved against said spring toward either end of said coupler whereby the end portion of said spacers retracted from between the locking surfaces at one end of said coupler is received within said internal longitudinal locking finger recesses thereby permitting said locking surfaces of said fingers at said end of said coupler to be moved closer together for releasing said end of said coupler for coupling and uncoupling said end of said coupler.

16. A coupler in accordance with claim 15 wherein said spacers each have longitudinal flange means engageable with corresponding side surfaces of the locking fingers along opposite sides of each of said spacers whereby said spacers are movable along said locking finger side surfaces between locking and release positions of said spacers.

17. A coupler in accordance with claim 13 wherein each of said spacers is provided with longitudinally spaced external laterally extending locking recesses positioned along each of said spacers to receive said internal locking flanges of said latch rings whereby when said spacers are at neutral locking positions along said locking fingers and said latch rings are at said first positions of rotation the locking flanges of one of said latch rings is received in the locking recesses of said spacers toward one end of said coupler and the locking flanges of the other of said latch rings are received in the other locking recesses of said spacers toward the other end of said coupler whereby said spacers are locked by said latch rings against movement in either direction relative to said locking fingers and rotation of either of said latch rings to said second position of said latch rings releases said spacers whereby movement of the other of said latch rings toward said rotated latch ring displaces said spacers along said locking fingers toward said rotated latch ring for releasing the locking bosses at the end of said coupler away from which said spacers are moved for coupling and uncoupling at said end.

Claims

2. A coupler in accordance with claim 1 wherein said locking members have locking surfaces engageable by said spacer means for holding said locking members in spaced locking relation at said first position of said spacer means when said spacer means is disposed between said locking surfaces and said locking surfaces being coengageable at one end of said coupler upon movement of said spacer means to one of said other positions at which said spacer means is removed from between said locking surfaces at said end of said coupler.

6. A coupler for interconnecting spaced bodies comprising: elongate locking fingers supported in longitudinal alignment spaced for lateral movement at each end thereof between a first spaced locking relationship and a second engaging release relationship; and an elongate spacer disposed between said locking members and movable between a first central position holding said fingers at each end of said coupler at said first spaced locking relationship and end positions toward either end of said locking fingers for releasing said fingers for movement toward each other at the other end of said fingers while holding said fingers in spaced locking relationship at the end toward which said spacer is moved.

8. A coupler in accordance with claim 7 including latch ring means operatively associated with said spacer for holding said spacer at said first position at one position of rotation of said latch ring and being rotatable to a second position of rotation for releasing said spacer for longitudinal movement to said end position.

11. A coupler in accordance witH claim 10 wherein each of said spacers has spaced external spring retainer flanges positioned on said spacers in alignment with said spring retainer flanges on said locking fingers when said spacers are centrally disposed along said locking fingers, said spring being confined between said spacer flanges.

12. A coupler in accordance with claim 10 including a pair of latch rings disposed around said locking fingers and spacers and spaced on said fingers and spacers at opposite ends of and engaged with said spring, one of said latch rings being biased toward the spring flanges on said locking fingers toward one end of said locking fingers and the other of said latch rings being biased toward the spring flanges toward the other end of said locking fingers, each of said latch rings being rotatable between a first locking position for holding said spacers against movement in the direction of the end of said locking fingers adjacent to said latch ring and movable to a second position of rotation for releasing said spacers for movement toward said adjacent end of said locking fingers.

13. A coupler in accordance with claim 12 wherein each of the said latch rings has a laterally extending key slot defining recesses toward each side of each latch ring on the side of said ring facing the spring flanges on the locking fingers toward which said ring is biased, said key slot being adapted to receive said spring flanges at said first position of each of said latch rings for releasably locking each of said latch rings against rotation relative to said locking fingers and spacers, said latch rings having internal recesses toward opposite sides of said rings extending in a direction of the axis of each of said rings for receiving said spacers whereby said spacers are released for movement relative to each of said rings when each of said rings is rotated to said second position, each of said rings having internal locking flanges, and each of said spacers having locking recesses for receiving one of said locking flanges in said latch rings for holding said spacers against movement relative to said latch rings when said latch rings are at said first positions of rotation on said coupler.