Abstract:
A locking device for a tool, such as a ratchet wrench, having a jointed drive head which may be situated in a series of angular positions relative to a handle, and which has means for temporarily holding the drive head of the tool at a predetermined angle with respect to the handle. The tool includes a spring-biased locking element disposed in the handle and which may be either engaged with, withdrawn from, or disengaged from the drive head. In the engaged position, the tool drive head is locked in place by the locking element. In the withdrawn position, the locking element is withdrawn from the head, and held away from it by the user to permit continuous changes in the angular relationship between the handle and the drive head. Finally, in the third orientation, the locking element is withdraw from the head and secured in a temporary holding position, allowing continual changes in the angular relationship between the handle and the head without the need for the user to continually hold the locking element.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application on application having Ser. No. 09/024,375, filed on Feb. 17, 1998 U.S. Pat. No. 6,167,787, which is a continuation application on application having Ser. No. 08/878,231, filed Jun. 18, 1997; U.S. Pat. No. 5,943,924 and which latter application is a continuation application of the application having Ser. No. 08/398,691, filed on Mar. 6, 1995, all of said applications still owned by the applicant herein abandoned. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     This invention relates generally to tools, and in particular to a locking device for tools such as ratchet wrenches having a handle portion and a head portion, the head portion being rotatably attached to the handle portion such that the head portion may be selectively positioned and locked in place in a plurality of angular relationships with respect to the handle portion. 
     Mechanics and other persons having reason to use ratchet wrenches frequently encounter situations where a nut to be removed or installed is either very difficult to reach, or, if accessible, is in such an awkward attitude or is obscured by an intervening structure in such a way that it is difficult to apply actuating torque. Solutions to these problems often involve the use of ratchet wrenches having head portions secured to the handle portion by means of a pivot hinge, allowing the head portion to be held at an angle relative to the handle portion. Many different locking means have been developed to secure the head in numerous selected angles relative to the handle portion of such ratchet wrenches. However, these locking means are often difficult to manipulate, making the tool awkward to use, particularly when held in one hand. 
     It is therefore, the principal object of this invention to provide, for a tool having a head portion adjustable at an angle relative to a handle portion, a locking mechanism which is both rugged and simple to manipulate. 
     BRIEF SUMMARY OF THE INVENTION 
     The primary object of this invention is to provide, for a tool having a head angularly adjustable relative to a handle portion a locking mechanism to secure the head in at a selected angular position. 
     A further object of this invention is to provide a locking mechanism which may be secured in a released position, allowing the angular position of the head relative to the handle portion to be smoothly and continually adjusted. 
     A further object of this invention is to provide a rugged locking mechanism which may be easily manipulated to either secure or release the head. 
     In accordance with the invention, generally stated, a ratchet wrench having a ratchet head and a drive handle is provided with at least one articulating joint which allows the ratchet head to be rotated approximately 180 degrees relative to the handle. A locking mechanism is provided to releasably lock the ratchet head in one of several angular positions relative to the drive handle. When in the locked position, the locking mechanism prevents rotation of the ratchet head, and will not be dislodged by application of pressure to the ratchet head, such as occurs during the application of torque. To release the locking mechanism, a locking element is withdrawn from engagement with the ratchet head, and either held away from the head during rotation, or rotated laterally into a locked-open position, allowing free rotation of the ratchet head. 
     The foregoing and other objects, features, and advantages of the invention as well as presently preferred embodiments thereof will become more apparent from the reading of the following description in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     In the accompanying drawings which form part of the specification: 
     FIG. 1 is an elevational view of an adjustable head ratchet wrench with the preferred embodiment of the locking mechanism of the present invention engaging the adjustable head; 
     FIG. 1A is a an elevational view of the adjustable head ratchet wrench of FIG. 1 with the locking mechanism shown released from the adjustable head and laterally locked in a neutral position; 
     FIG. 2 is a side elevational view of the embodiment shown in FIG. 1; 
     FIG. 3 is a side elevational view similar to FIG. 2, with the adjustable head shown in various selected angular positions relative to the ratchet wrench handle; 
     FIG. 4 is an exploded view of the embodiment shown in FIG. 2, illustrating the internal components of the locking mechanism; 
     FIG. 5 is a side elevational view similar to FIG. 3, illustrating an extreme angular adjustment of the adjustable head relative to the handle portion, and a handle extender fitted to the handle; 
     FIG. 6 is a top elevational view of the embodiment shown in FIG. 5; 
     FIG. 6A is a side elevational view of a locking pin component of the preferred locking mechanism; 
     FIG. 6B is a top elevational view of a handle extender shown in FIG.  6 A. 
     FIG. 7 is a front elevational view of the embodiment shown in FIG. 5; 
     FIG. 8 is an illustration of an alternate embodiment locking mechanism of the present invention, including a spring loaded locking collar securing an adjustable head relative to a ratchet wrench handle; 
     FIG. 9 is a side illustration of the embodiment shown in FIG. 8; 
     FIG. 10 is an exploded illustration of the alternate embodiment shown in FIG. 9, illustrating the internal components of the locking mechanism; 
     FIG. 11 is a side elevational view of an alternate embodiment locking mechanism of the present invention, illustrating separate and independent locking elements; 
     FIG. 12 is a top elevational view of the embodiment shown in FIG. 11; 
     FIG. 12A is an illustration of an alternate embodiment locking mechanism of the present invention, incorporating an axial locking pin shown released from the adjustable head and laterally locked in place, and securing the adjustable head via side pivot points; 
     FIG. 12B is an illustration of the alternate embodiment shown in FIG. 12A as viewed from a different angle; 
     FIG. 12C is an illustration of the embodiment shown in FIG. 12A, with the adjustable head locked parallel to the handle; 
     FIG. 13 is a top elevational view of an alternate embodiment of the locking mechanism of the present invention, including a transversely mounted locking element intermeshing with the base of the adjustable head; 
     FIG. 14 is a side elevational view of the embodiment shown in FIG. 13; 
     FIG. 15 is an exploded view of the embodiment shown in FIG. 13, illustrating the internal components of the locking mechanism; 
     FIG. 16 is side view of the components shown in FIG. 15; 
     FIG. 16A is a side elevational view of one embodiment of the transversely mounted locking element; 
     FIG. 16B is a side elevational view of a second embodiment of the transversely mounted locking element; 
     FIG. 17 is an exploded side elevation of an alternate embodiment of an adjustable head ratchet wrench incorporating a tongue and groove locking mechanism of the present invention 
     FIG. 18 is an exploded top elevation of the embodiment shown in FIG. 17; 
     FIG. 19 is an exploded top elevation of an alternate embodiment of an adjustable head ratchet wrench incorporating a toothed locking mechanism of the present invention; 
     FIG. 20 is an exploded side elevation of the embodiment shown in FIG. 19; 
     FIG. 21 is an exploded side elevation similar to FIG. 16, illustrating an alternate configuration for the transversely mounted locking element; 
     FIG. 22 is a partial exploded top elevation similar to FIG. 15, incorporating the alternate configuration of FIG. 21; 
     FIG. 23 is an exploded and cut-away perspective view of the alternate embodiment shown in FIG. 21; 
     FIG. 24 is an illustration of a alternate embodiment of a ratchet wrench employing dual locking elements of the present invention to provide a greater variety of angular positions within which the adjustable head may be positioned relative to the handle; 
     FIG. 25 is an exploded top illustration of the embodiment shown in FIG. 24, illustrating the internal components of the dual locking mechanisms of the present invention; 
     FIG. 26 is an illustration of an alternate embodiment of the double-jointed locking swivel wrench of the present invention illustrated in FIGS. 24 and 25; 
     FIG. 27 is an illustration of an alternate embodiment of the locking swivel wrench of the present invention illustrated in FIG. 12, detailing internal structures of the handle; 
     FIG. 28 is an illustration of an alternate embodiment of the locking swivel wrench of the present invention illustrated in FIG. 12, detailing internal structures of the locking mechanism; 
     Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following detailed description illustrates the invention by way of example and not by way of limitation. The description will clearly enable one skilled in the art to make and use the invention, describes several embodiments, adaptations, variations, alternatives, and uses of the invention, including what we presently believe is the best mode of carrying out the invention. 
     FIGS. 1 to  7  illustrate the preferred embodiment of the swivel wrench lock of the present invention, indicated generally by reference numeral  100  in the drawings. Tool  100  has an adjustable drive handle  102  with an integral dual receptacle to fit any ⅜″ socket extension  109  or ½″ socket extension  113  to be used as a handle to apply torque, and an articulating drive head  104 . The handle  102  has a body section  106  with a first flared end section  108  and a second flared end section  110  which is integrally attached to a U-shaped frame  112 . The frame  112  has two opposed arms  114  and  116  which define a space  118 . As best seen in FIG. 1A, communicating between the flared end  110  and the U-shaped frame  112 , a hook-shaped slot  120  locks a spring biased pin actuator  122  in a neutral position to unlock the drive head  104  for easy adjustment. Shown in FIG. 6A, the actuator  122  has a locking pin  124  biased outwardly towards the space  118  by a bias spring  126  which seats in a bore  128  formed in the pin actuator  122 . The bias spring  126  also seats in a bore  130  formed in the body section  106 . The pin actuator  122  further includes a thumb pad  132  to provide a tactile engaging surface. As can be seen in FIGS. 2 through 4, the respective arms  114  and  116  have holes  134  formed adjacent to their respective ends to seat a pivot pin  136 , securing the drive head  104  to the dual receptacle drive handle  102 . 
     The drive head  104  includes a conventional ratcheting socket drive  138  with a detent ball  140 . The ratcheting gearworks (not shown) in the drive head are controlled by a thumb lever  142 . The drive head  104  tapers to a base  144 , and a pivot arm  146  extends from the base. The pivot arm  146  has a rounded end  148  with a plurality of stop holes  150  formed in the radiused portion of the end  148 . The stop holes  150  are dimensioned to allow the insertion of the locking pin  124  therein. A pivot hole  152  is formed through the pivot arm  146 . The pivot arm  146  fits between arms  114  and  116 , and is secured in place by the pivot pin  136  inserted through the pivot holes  134  and  152 . 
     FIG. 3 best illustrates the articulating features of tool  100 . The user can move the spring biased pin actuator  122  and retract the locking pin  124  from a stop hole  150 , allowing the drive head  104  to then pivot freely about the pin  136  until it is in a desired angular position relative to the handle  102 . The locking pin  124  and actuator  122  or  380  may be either held away from the stop hole  150  and drive head  104  manually or, once withdrawn, may be rotated laterally into the hook portion of the hook-shaped slot  120  or  366  as shown in FIGS. 1A,  12 A and  12 B. Releasing the spring-biased pin actuator in the hook portion of slot  120  will retain the locking pin  124  or  372  away from the stop hole  150  and drive head  104 , allowing the drive head to continue to rotate freely. 
     To lock the drive head  104  at a desired angular relation to the handle  102 , the user rotates the pin actuator laterally out of the hook portion of slot  120  if necessary, and then releases the spring biased pin actuator  122  allowing the bias spring  126  to drive the locking pin  124  into a stop hole  150  aligned with the pin. When the locking pin  124  is driven into a stop hole  150 , the drive head  104  of the tool is locked in position relative to the handle  104 . As shown in FIGS. 4 through 7, the stop holes  150  are arranged around the radiused end  148  in such a manner that the drive head  104  can be articulated through approximately 180 degrees relative to the handle  102 . Rotation of the drive head  104  relative to the handle  102  allows the tool  100  to apply torque in hard to reach places. FIGS. 5 and 6 depict a ½″ socket extension  115  connected to the dual receptacle drive handle  113 . The socket extension  115  has a integral dual receptacle to fit any ⅜″ socket extension  117  or ½″ socket extension  119  for adding additional socket extensions. The socket extension  115  has an external hex bolt  121  formed on one end for applying lateral torque with adjustable wrenches or socket wrenches (not shown). 
     FIGS. 8 to  10  illustrate an alternate preferred embodiment of the swivel wrench lock of the present invention, indicated generally by reference numeral  200 . Tool  200  has a handle  202  with an integral dual receptacle to fit and ⅜″ socket extension  205  or ½″ socket extension  207  to be used as a handle to apply torque, and an articulating drive head  204 . The handle  202  includes a base section  206 , with a tapered shoulder  208 . An elongated rod  210  extends outwardly from the shoulder  208 . The rod  210  has a locking groove  212  formed in the surface adjacent to the shoulder  208 , and a flattened forward segment  214  with a pivot hole  216  formed therein. The locking groove  212  further includes a locking slot  215  adjacent the shoulder  208 , extending perpendicular to the groove  212  around a thirty degree arc of the circumference of the rod  210 . Surrounding the rod  210 , a bias spring  218  is seated on the rod  210  and is retained thereon by a locking pin collar  220 , seated on the forward segment of the rod. 
     The locking pin collar  220  is generally tubular in shape and has a pair of integral locking pins  222 A and  222 B extending outwardly from the sides of the collar on opposite sides of the forward segment  214 . There is an axial bore  224  formed through the collar, having a first chamber  226  and a second chamber  228 . The chambers are separated by an internal shoulder  230 . A detent  232  protrudes into chamber  226 , such that it is aligned within the locking groove  212  when the collar  220  surrounds the rod  210 . Accordingly, the chamber  228  is dimensioned to allow the bias spring  218  to seat therein and abut the shoulder  230 , and the chamber  226  is dimensioned to allow the insertion of the flattened forward segment  214  of the rod  210  therethrough. 
     Drive head  204  includes a conventional ratcheting drive  234  with a spring biased detent ball  236  in a cavity  238 . A conventional thumb control  240  operates the ratcheting gearworks (not shown) inside the head  204 . The drive head incorporates an integral neck  242  having a pair of opposed tabs  244  and  246 , defining a space  248 . The outer ends of the respective tabs are radiused, and have a plurality of locking holes  250  formed therein. The locking holes  250  are dimensioned to allow the insertion of the engaging pins  222 A and  222 B therein. Each tab includes a pivot hole  252  formed transversely therein, positioned such that when the flattened forward segment  214  of the rod  210  seats in the space  248 , a pivot pin  254  may be inserted through the holes  252  in the tabs, as well as the hole  216  in the rod to pivotally secure the drive head to the handle. 
     In use, the bias spring  218  urges the locking pin collar  220  towards the drive head  204 , engaging pins  222 A and  222 B into the locking holes  250 , to lock the drive head in an angular position relative to the handle  202 . The collar  220  may be drawn back against the bias spring  218 , withdrawing the engaging pins out of the locking holes and allowing the drive head  204  to pivot about the pivot pin  254  until a desired angular relationship with the handle  202  is reached. The locking pin collar  220  can be retained in a withdrawn position by pulling it back until the detent  232  is aligned with the lock slot  215 , and then rotating the locking pin collar laterally to engage the detent in the locking slot  215 . The bias force of the bias spring  218  will retain the locking pin collar  220  in the locking slot  215  until released by lateral rotation. The release of the locking pin collar  220 , and the bias spring  218 , either from the locking slot  215  or the withdrawn position will drive the locking pins  222 A and  222 B into the locking holes  250 , locking the drive head in the desired angular position. The holes are positioned along the tabs  244  and  246  such that the drive head  204  can be rotated through an arc of approximately 180 degrees relative to the handle. Rotation of the drive head  204  relative to the handle  202  allows the tool  200  to apply torque in hard to reach places. 
     FIGS. 11 and 12 illustrate another preferred embodiment of the locking swivel wrench lock of the present invention, indicated generally by reference number  300 . Tool  300  has a drive handle  302 , terminating in a pair of opposed arms  304  and  306  on the first or upper end of the handle. The arms define a space  308  wherein a drive head  310  is supported, and are prevented from movement by a threaded support pin  311 . Each arm  304  and  306  includes a bias spring  312  seated in a bore  314  adjacent to the upper end of the respective arm. The upper ends of each arm  304  and  306  include identical pivots  316 , each supporting a thumb actuated pivotal locking pin  318  rotatably attached to the pivot  316  such that rotation of the locking pins  318  engages and disengages the drive head  310 . 
     The drive head  310  is seated in space  308  with clearance to rotate through a full 360 degree arc. The drive head  310  includes a first boss  320  with a spring seating bore  322  formed therein, and a second boss  324  with a second spring seating bore  326  formed therein, integrally formed on the opposite sides and aligned with the bores  314  on the arms  304  and  306 . Pivot pins (not shown) are seated inside each spring  312 , and extend through bores  322  and  326  respectively, to seat in each bore  314 , pivotally holding the drive head  310  within space  308 . The drive head  310  further includes a number of locking holes  328  arranged in an arcuate pattern, forward of bosses  320  and  324 . 
     In a normally spring-biased position, each locking pin  318  is driven into one of the locking holes  328 , securing the drive head  310  against any rotation about the pivot pins (not shown). Each locking pin  318  can be actuated by exerting pressure against a lever portion  330 , causing the locking pin to pivot about point  316 , and withdraw from the locking hole  328 . Thus withdrawn, the drive head  310  can be moved in angularly relative to the drive handle  302 . The drive head  310  further includes a conventional ratchet drive  332 , thumbwheel actuator,  334  and ratcheting gearworks (not shown). 
     FIGS. 12A through 12C and FIGS. 27-28 illustrate another preferred embodiment of the swivel wrench lock of the present invention based upon a similar drive handle structure as the embodiment shown in FIGS. 11 and 12. Shown generally at  350 , the tool includes a drive handle  352 , with an integral receptacle (not shown) to fit any length ½″ socket extension to be used as a handle to apply torque, terminating at one end in two opposing arms  354  and  355 , which define a space  357 . A drive head  356  is supported in the space  357 , between the arms  354  and  355  by means of pivot pins  358  and  360 , extending laterally from the drive head and seating within an identical bore  362  in each arm  354  and  355 . A washer  364  is fitted around each pivot pin, between the drive head  356  and each arm, ensuring the drive head is free to rotate about an axis defined by the pivot pins  358  and  360 , with reduced frictional interference. 
     The drive handle  352  further includes a longitudinal hook-shaped slot  366 , terminating at the base  368  of the arms  354  and  355  which engages a spring biased pin actuator  370 . Shaped identical to the actuator shown in FIG. 6A, the actuator  370  has a locking pin  372  biased outwardly towards the space  357  by a bias spring  374  which seats in a bore  376  formed axially in the pin actuator  370 . FIG. 27 illustrates the locking pin  372  without the bias spring  374  for clarity. The bias spring  374  also seats in an axial bore  378  formed in the arm  354  and arm  355  at the base of the slot  366 . The pin actuator  370  further includes a thumb pad  380  to provide a tactile engaging surface. A threaded bore  373  shown in FIGS. 27 and 28 at the end of arm  355  and a threaded bore  375  at the end of arm  354  are held in place by drive handle  352  and secured by a bolt  377 . 
     The drive head  356  includes a conventional ratcheting socket drive  382  with a detent ball  384 . The ratcheting gearworks (not shown) in the drive head are controlled by a thumb lever  386 . The drive head  356  is formed as an oblate spheroid, with a plurality of stop holes  388  arrayed on the radiused portions, aligned with the locking pin  372 . An additional stop hole  389  is placed at the axial center of the thumb lever  386 . Each stop hole  388  is dimensioned to allow the insertion of the locking pin  372  therein. 
     Use of the tool  350  is substantially similar to that described above for the embodiment shown in FIGS. 1 through 7, with the added benefit that the drive head  356  is capable of rotating through a full 360 degrees relative to the drive handle  352 . The additional stop hole  389  placed on the thumb lever  386  allows the drive head to be secured in axial alignment with the drive handle, allowing the tool  300  to function as an extension ratchet. 
     FIGS. 13 through 16 illustrate another preferred embodiment of the swivel wrench lock of the present invention, indicated generally at  400 . Tool  400  has an adjustable drive handle  402  and an articulating drive head  404 . The handle  402  has a body section  406  with a first flared end section  408  with an integral dual receptacle (not shown) to fit any ⅜″ or ½″ socket extension to be used as a handle to apply torque. A second flared end section  410  is integrally attached to a U-shaped frame  412 . The frame  412  has two opposed arms  414  and  416  which define a space  418 . As best seen in FIG. 16, communicating between the flared end  410  and the U-shaped frame  412 , is a recessed portion  419  in the upper surface of section  410 . A transverse slot  420  at one end of the recessed portion  419  receives a thumb lock  422 . 
     The thumb lock  422 , best seen in FIG. 16A, includes a lever arm  424  on an upper surface  426 , a cylindrical body  428  with a flattened surface  430  extending downward from the upper surface, and a retaining flange  432  arrayed parallel to the upper surface. The cylindrical body  428  of the thumb lock  422  is received in the transverse slot  420 , with the upper surface  426  and lever arm  424  resting on the recessed portion  419  as seen in FIG.  13 . The radiused portion of the cylindrical body  428  includes a number of circumferential teeth  433 , and a retaining detent  434 . A bias spring  436  and detent ball  438  are fitted within an axial bore  440  in section  410 , such that rotation of the thumb lock  422  engages and disengages the detent ball  438  in the retaining detent  434 . 
     As can be seen in FIGS. 14 through 16, the respective arms  414  and  416  have holes  442  formed adjacent their respective ends to seat a pivot pin  444 , securing the drive head  404  to the handle  402 . The drive head  404  includes a conventional ratcheting socket drive  446  with a detent ball  448 . The ratcheting gearworks (not shown) in the drive head are controlled by a thumb lever  450 . The drive head  404  tapers to a base  452 , and a pivot arm  454  extends from the base. The pivot arm  454  has a rounded end  456  with a plurality of parallel locking grooves  458  formed in the radiused portion with a slightly larger diameter than the pivot arm  454 . The locking grooves  458  are dimensioned to mesh with the circumferential teeth  433  of the thumb lock  422 , and traverse more than 180° to provide a true 90° locking handle in either direction relative to the drive head. A pivot hole  460  is formed through the pivot arm  454 , with one side including a recessed seat  462  for a tension ring  464 . The pivot arm  454  fits between arms  414  and  416 , and is secured in place by the pivot pin  444  inserted through the pivot holes  442  and  460 , and tension  464 . 
     During use, the user can move the thumb lock  422  and engage or disengage the circumferential teeth  433  from the locking grooves  458 , allowing the drive head  404  to then pivot about the pin  444  until it is in a desired angular position relative to the handle  402 . When the teeth  433  are disengaged from the locking grooves  458 , the flattened surface  430  is aligned with the locking grooves, allowing the drive head  404  to rotate freely. Additionally, the bias spring  436  drives the detent ball  438  into the retaining detent  434 , holding the thumb lock in the released position until a rotation force sufficient to overcome the spring bias is exerted. To lock the drive head  404  at a desired angular relation to the handle  402 , the user rotates thumb lock  422  out of the release position, engaging the teeth  433  with the locking grooves  458 . When the teeth and grooves engage, the drive head  404  of the tool is locked in an angular position relative to the handle  404 . As shown in FIGS. 15 and 16, the locking grooves are arranged around the radiused end  456  in such a manner that the drive head  404  can be articulated through approximately 180 degrees relative to the handle  402 . Rotation of the drive head  404  relative to the handle  402  allows the tool  400  to apply torque in hard to reach places. 
     FIGS. 17 through 20 illustrate alternate embodiments of the locking swivel wrench of the present invention illustrated in FIGS. 1 through 7. Turning to FIGS. 17 and 18, the locking pin  124  of actuator  122  in FIG. 6A is replaced with a locking tongue  500 , and the stop holes  150  are replaced with matching stop grooves  502 . Additionally, the pivot pin  136  in FIG. 2 is replaced with a combination of a threaded hinge pin  504  and a compression spring  506  seated in a recess  508  between the drive head base  144  and the arm  116  of the frame  112 . FIGS. 19 and 20 are identical to FIGS. 17 and 18, however, the locking tongue  500  and matching stop grooves  502  are replaced with locking teeth  510  and matching stop radial recesses  512 , allowing multiple teeth and recesses to mesh when locking the drive head  104  in position and traversing more than 180° to provide a true 90° locking handle in either direction relative to the drive head. 
     FIGS. 21 through 23 illustrate an alternate embodiment of the swivel wrench lock of the present invention illustrated in FIGS. 13 through 16. The thumb lock  422  includes an additional retaining flange  514 , located directly below, and parallel to, the lever arm  424 . A corresponding recessed slot  516  is located adjacent the transverse slot  420 , and receives the retaining flange  514  when the thumb lock  422  is inserted therein. The retaining flange  514  aids in stabilizing the thumb lock  422  during rotation. 
     FIGS. 24 and 25 illustrate an alternate embodiment of the locking dual swivel wrench of the present invention, indicated generally at  600 . Tool  600  includes a multi-sectioned handle  602  and an articulating drive head  604 . The handle  602  includes a body section  606  with a radiused end  608 , and an intermediate connector  610 . The connector  610  has an axial bore  612 , and terminates at opposite ends in U-shaped frames  614  and  616 , each identical to frame  412  shown in FIG.  13 . The bore  612  extends through connector  610 , and opens into spaces  618  and  620 , defined by frames  614  and  616  recessed portions  622  and  624  in the upper surface of the connector. A transverse slot  626  and  628  at the end of each respective recessed portion receives a thumb lock  422 , the construction and operation of which is described above in connection with FIGS. 13-16 and  21 - 23 . Bias spring  630 , seated in bore  612  replaces bias spring  436 . The length of bias spring  630  is sufficient that detent ball  632  and  634 , placed at opposite ends of the spring are sufficiently biased to retain the respective thumb locks  422  in the disengaged positions as described above. 
     The drive head  604  of this embodiment is constructed identically to drive head  404 . Correspondingly, drive handle  602  includes a number of parallel locking grooves  636  on the radiused end  608  to interlock with the thumb lock  422  located in recess  624 . The drive handle  602  is pivotally linked to connector  610  by means of a pivot pin  638  inserted through bores  640  and  642  in the arms of frame  614 , and through bore  644  in the end  608 . 
     During use, either thumb lock  422  may be either engaged or disengaged with the corresponding locking grooves in drive handle  602  or the drive head  604 , allowing for double-jointed articulation. Double-jointed articulation allows the tool  600  to be employed in locations where a single-jointed tool would be incapable of exerting torque. 
     FIG. 26 illustrates an alternate embodiment of the double-jointed dual locking swivel wrench lock of the present invention illustrated in FIGS. 24 and 25. Indicated generally at  700 , the tool incorporates the drive handle  402 , drive head  404 , and thumb lock  422  of FIG. 13 with an intermediate connector  702  including a single U-shaped frame  704  and a radiused end  706 . The frame  704  is constructed identical to frame  412 , and  704  and a radiused end  706 . The frame  704  is constructed identical to frame  412 , and incorporates the structures needed to support a thumb lock  422 , including a bore  708 , bias spring  710 , detent ball  712 , and recessed portion  714 . The radiused end  706  has locking grooves  716 , constructed identical to the locking grooves  458  on drive head  404 . 
     The drive handle  402  is pivotally connected to the radiused end  706  by means of a pivot pin  718 , and the drive head  404  is similarly connected to the frame  704  by means of a second pivot pin  720 . This allows for double-jointed articulation of the drive hand and the drive head relative to each other, allowing the tool  700  to be employed in locations where a singlejointed tool would be incapable of exerting torque. 
     One skilled in the art will further recognized that additional numbers of joints may be employed in the locking dual swivel wrench, and that a variety of locking mechanisms including each of those described above may be incorporated to engage and disengage the drive head from the drive handle, allowing angular adjustments to be made. 
     In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results are obtained. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.