Patent Publication Number: US-6658770-B2

Title: Implement coupling assembly for excavating machines and the like

Description:
This invention relates to excavating machines and the like, and more particularly to an assembly for detachably coupling an implement to a dipper stick of such machines. 
     BACKGROUND OF THE INVENTION 
     In the construction, mining and other industries, it is highly desirable to readily couple and uncouple different implements such as buckets, grapples, rakes and the like relative to the dipper stick of such machines in order to enhance productivity. Preferably, the assemblies for readily coupling and uncoupling such implements should be simple in design to minimize manufacturing costs, easy to mount on conventional dipper sticks and readily operable to quickly and reliably couple and uncouple the implement onto and off of a dipper stick. 
     In view of the foregoing, the principal object of the present invention is to provide an assembly for detachably coupling an implement to the dipper stick of a machine, which meets such criteria of design, installation and use. 
     SUMMARY OF THE INVENTION 
     The present invention meets the requirements of the aforementioned criteria by providing an assembly mountable on a dipper stick and a fluid actuated assembly of a machine, and connectable to an implement having at least one pair of opposed, connecting pin receiving recesses, generally comprising at least one spacer link including a pair of segments pivotally connected together and angularly displaceable relative to each other between retracted, inoperable and extended, operable positions, one of such a link segments having a pin portion connectable to the dipper stick for pivotal movement about its axis and receivable in one of the implement recesses, and the other of the link segments having a pin portion operatively connectable to the fluid actuated assembly for pivotal movement about its axis and receivable in the other of the implement recesses, and means mounted thereon and cooperable with the one link segment when the link segments are disposed in their extended, operatively positions for releasably securing the link segments in their extended, operative positions. Preferably the assembly includes a pair of such links, each disposed on a side of the dipper stick. In addition, the releasably securing means comprises a latch on one of the link segments, cooperable with the other link segment when the link segments are in their extended, operative positions, for preventing the link segments from displacing from their extended, operative positions to their retracted, inoperable positions. In one embodiment, the latch may comprise a toggle bolt pivotally connected to one of the main link segments and receivable within a recess of the other link segment to releasably secure the segments together. In another embodiment of the invention, such a latch may comprise a spring biased pin mounted in one of the link segments and receivable in a registrable opening in the other link segment when the link segments are disposed in their extended, operable positions, with a pin disposed in such opening in the other link segment which may be displaced to eject such spring biased pin from the opening in the other link segment to permit the link segments to pivot from their extended, operative positions to their retracted, inoperable positions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view of an embodiment of the invention illustrating the coupling assembly thereof in a collapsed, inoperative condition; 
     FIG. 2 is a view similar to the view shown in FIG. 1, illustrating the coupling assembly in its expanded, operative condition; 
     FIG. 3 is an enlarged, perspective view of the coupling assembly shown in FIGS. 1 and 2, illustrating certain components in exploded relation and having portions thereof broken away; 
     FIG. 4 is a perspective view of another coupling assembly embodying the present invention; 
     FIG. 4A is an enlarged cross sectional view taken along line  4 A— 4 A in FIG. 4, illustrating a latch mechanism in a latched condition; 
     FIG. 4B is a view similar to the view shown in FIG. 4A, illustrating the latch mechanism in an unlatched condition; 
     FIG. 5 is a perspective view similar to the view shown in FIG. 4, illustrating an embodiment provided with an alternate latch mechanism; 
     FIG. 5A is a cross sectional view taken along line  5 A— 5 A in FIG. 5, illustrating the latch mechanism in a latch condition; and 
     FIG. 5B is a view similar to the view shown in FIG. 5A, illustrating the latch mechanism in an unlatched condition. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
     Referring to FIGS. 1 and 2 of the drawings, there is illustrated a dipper stick  10  of a excavating machine, an implement in the form of an excavating bucket  11  and an assembly  12  for coupling the implement to the free end of the dipper stick in the conventional manner. Dipper stick  10  is of a conventional construction and is pivotally connected at an upper end thereof to a boom, and is pivotal relative to such boom by means of a fluid actuated cylinder assembly. Rotatably mounted on the free end of dipper stick  10  is a first connecting pin  13  having a transversely disposed axis. Spaced from pin  13  is a mounting pin  14  having a transverse axis on which a pair of support links  15 ,  15  are mounted for pivotal movement in parallel planes, relative to the dipper stick. The free ends of the support links are pivotally connected to a connecting pin  16  on which there also are pivotally connected the upper ends of a pair of actuating links  17 ,  17 . Operatively interconnecting the under side of the dipper stick and connecting pin  16  is a fluid actuated assembly  18  including a cylinder member having the base end thereof pivotally connected to a set of brackets mounted on the underside of the dipper, and a rod member  19  pivotally connected at its free end to connecting pin  16 . 
     Bucket  11  is of a conventional configuration except for the mounting brackets. It is provided with a pair of laterally spaced sidewalls  20 ,  20  an adjoining wall including an upper wall section  21 , a downwardly and forwardly curved, rear wall section  22  and a forwardly extending bottom wall section  23  terminating at a front cutting edge  24 . Rigidly secured to the upper wall section  21  and rear wall section  22  is a pair of identical, laterally spaced mounting brackets  25 ,  25 . As best seen in FIG. 1, each of the brackets is recessed in an upper edge thereof, as at  26 , providing an entry or access passageway and a pair of lower guide surfaces  27  and  28  inclined toward a pair of opposed pin receiving recess portions  29  and  30 . 
     Coupling assembly  12  is best seen in FIG.  3  and includes a connecting pin  13 , a connecting pin  31  spaced from and parallel to connecting pin  13  and a pair of identical spacer links  32 ,  32 . Each spacer link includes a first link segment  33  rigidly mounted on connected pin  13  and projecting substantially radially therefrom, a second link segment  34  rigidly connected to an end of connecting pin  31  and projecting substantially radially therefrom and a pin  35  pivotally connecting overlapping, free ends of link segments  33  and  34 . Mounted on an upper edge of link segment  33  and extending beyond the free end, thereof is a plate member  36  having a recess  37  disposed in a forwardly disposed edge  38 . Mounted on a pin  39  rigidly secured to link segment  34  is a toggle bolt  40  having a shank portion  41  adapted to be received through recess  37  of plate member  36  when each spacer link  32  is in an extended, operative condition as shown in FIGS. 2 and 3. The shank portion of the toggle bolt extends through recess  37  and is threaded to receive either a threaded nut  42  or a knurled knob  43  to releasably secure the shank portion of the toggle bolt within recess  37  and correspondingly the link segments in their extended, operative position as shown in FIGS. 2 and 3. A locking pin  44  may be used with the hex nut  42  which is adapted to be inserted in registrable openings in the shank portion of the toggle bolt and hex nut  42  to prevent the nut from running off of the toggle bolt when the assembly is in use. 
     The spacer link shown in FIG. 3 is adapted to be positioned on one side of the dipper stick as shown in FIGS. 1 and 2 and the other such spacer link is adapted to be positioned on the other side of the dipper stick. When connecting pins  13  and  31  are displaced toward each other, the link segments of each spacer link will be caused to angularly displace towards each other to retracted, inoperative positions as shown in FIG. 1, and when such connecting pins are displaced apart, the link segments of each spacer will be caused to angularly displace apart to extended, operative positions as shown in FIG.  2 . As a set of link segments angularly displace apart to positions as shown in FIG. 3, plate member  36  will engage an upper edge of link segment  34  to position recess  37  for receipt of the shank portion of toggle bolt  39 . Link segment  33 , recess  37  and toggle bolt  40  are adapted to pivot in the same plane so that when a pair of link segments are angularly displaced as shown in FIG. 3, recess  37  will be properly aligned to receive the shank portion of toggle bolt  40 . 
     With bucket  11  positioned on the ground and assembly  12  disposed in the retracted, inoperable condition as shown in FIG. 1, such bucket may be coupled to the dipper stick by first manipulating the dipper stick to insert the ends of connecting pin  13  in the forwardly disposed recess portions of the mounting brackets on the implement, and then operating the actuating assembly  18  to cause link segments  33  and  34  to angularly displace apart, and correspondingly the end portions of connecting pin  27  to be inserted in the rearwardly disposed recess portions of the mounting brackets. As the dipper stick and the actuating assembly are thus maneuvered to insert connecting pins  13 ,  31  into oppose recesses  30  and  29 , respectively, connecting pin  13  will be caused to engage guide surface  29  and be guided into recesses  30  and connecting pin  31  will be caused to engage guide surface  27  and thus be guided into recess  29 . When connecting pins  13  and  31  are thus positioned in mounting brackets  25 ,  25  and plate number  36  engages the upper surface of link segment  34 , the toggle bolt on each link segment  34  is swung upwardly to insert the shank portion thereof within aligned recess  37  and a nut  42  or a knob  43  is threaded onto the threaded shank portion and tightened against plate number  36  to firmly secure the coupling assembly in its extended, operative condition with the implement pivotally connected to the dipper stick. 
     To uncouple the bucket from the dipper stick, the coupling procedure as described is essentially reversed. Nut  42  or knob  43  is first removed, the toggle bolt is then pivoted out or permitted to fall out of recess  37 , actuating assembly  18  is operated to cause the link segments to angularly displace toward each other and thus cause connecting pin  31  to be removed from recesses  29 ,  29  and then the dipper stick is maneuvered to remove connecting pin  13  from recesses  30 ,  30 . The dipper stick may then be maneuvered and actuating assembly  18  may be operated to couple another implement having a set of mounting brackets similar to mounting brackets  25 ,  25  to the dipper stick in the manner as described. 
     To accommodate dipper sticks of different thickness or implement mounting brackets of different sizes, adapter bushings  45  may be provided on the ends of the connecting pins. Such bushings include a cylindrical portion  46  adapted to receive a connecting pin and having different lengths and diameters, and an annularly portion  47  adapted to bear against a sidewall of the dipper stick. 
     Referring to FIGS. 4,  4 A and  4 B, there is illustrated a coupling assembly  50  embodying the present invention which may be used in a manner similar to coupling assembly  12  to detachably couple implement  11  to dipper stick  10 . Generally, assembly  50  includes a pair of spaced, parallel connecting pins  51  and  52  comparable to connecting pins  31  and  13  of assembly  12 , and a pair of transversely spaced, parallel spacer links  53  and  54 . The spacer links are adapted to straddle the lower end of the dipper stick and are substantially similar in construction and operation. As best shown in FIG. 4, spacer link  53  includes a link segment  55  rigidly secured to an end portion of connecting pin  52  and disposed substantially radially relative thereto, and a link segment  56  rigidly secured to an end portion of connecting pin  51  and disposed substantially radially relative thereto. The free ends of such segments are disposed in overlapping relation and are pivotally connected together by means of a bolt  57 . 
     The segments of spacer links  53  and  54  are adapted to be maintained in their extended, operative positions as shown in FIG. 4 by means of a pair of latch mechanisms  58  and  59  mounted on the spacer links. Such mechanisms are substantially identical in construction and operation. As best shown in FIGS. 4A and 4B, latch mechanism  58  includes a housing  60  mounted on link segment  56  overlying a circular opening  61  therein, and a housing  62  secured to link segment  55  overlying, a circular opening  63  therein adapted to register with opening  61  in link segments  55  and  56  when such segments are in their extended, operative positions as shown in FIG.  4 . Housing  60  is secured to link segment  56  by means of a set of bolts  64  and is provided with a cylindrical opening  65  in an end wall  66  thereof, disposed coaxially with opening  61  and having an enlarged section  67  having a diameter equal to the diameter of opening  61 . Disposed within enlarged section  67  and opening  61  is a cylindrical guide sleeve  68  in which there is disposed a latch member  69  which is adapted to displace axially within guide sleeve  68 . An outer face  70  of latch member  69  is provided with an axial opening  71  having an enlarged section  72 . Mounted in opening  71  and extending into and projectable beyond opening  65  in the housing is a guide pin  73 . Latch member  69  is urged away from end wall  60  of housing  58  by means of a coil spring  74  received within enlarged section  72  of the latch member and interposed between an annular end wall of enlarged section  72  and housing end wall  60 . As best shown in FIG. 4B, the axial dimension of latch member  69  is the same or slightly less than the axial dimension of guide sleeve  68  so that when the latch member is fully retracted within guide sleeve  68  to compress spring  74 , it will be received entirely within guide sleeve  68  to permit link segments  55  and  56  to annularly displace relative to each other about the axis of pivot bolt  57 . 
     Housing  62  is similar in construction to housing  60  and is firmly secured to link segment  55  overlying cylindrical opening  63  by means of a set of bolts  75 . The inner face of such housing is provided with a recess having a cylindrical wall  76  having a diameter similar to the diameter of opening  63 , and an end wall  77 . Disposed within such recess and opening  63  is a cylindrical guide sleeve  78  which is adapted to be axially aligned with guide sleeve  68  when link segment openings  61  and  63  are registered. Disposed within guide sleeve  68  is a piston member  79  having an inner face  80  engageable with an inner face  81  of latch member  69 . Housing  62  further is provided with a fluid passageway  82  interconnecting an inlet  83  and an outlet communicating with a chamber defined by the end wall of housing  62 , guide sleeve  76  and piston member  79 . Inlet  83  is adapted to be connected through a fluid line to a source of fluid under pressure provided with suitable control means for selectively applying fluid under pressure to fluid passageway  82 . It will be appreciated that upon applying fluid under pressure to passageway  82 , piston member  79  will be caused to displace axially to correspondingly displace latch member  69  against the biasing action of coil spring  74 . To accommodate such displacement, the outer face of piston member  79  is provided with a recess  84  communicating with the outlet of passageway  82  to provide a greater bearing surface for fluid injected through passageway  82  and acting upon piston member  79 . 
     Whenever coupling assembly  50  is in its extended, operative condition with the link segments thereof in their extended, operative positions and openings  61  and  62  registered, the biasing action of coil springs  74  will cause the latch members of mechanisms  58  and  59  to displace into the guide sleeves of the aligned housing to latch the link segments in their extended, operative positions. When it is desired to unlatch the link segments, fluid under pressure is applied to passageways  82  to cause the piston members in the mechanisms to displace and correspondingly displace the latch members against the action of the coil springs. Under such circumstances, the latch members will be caused to be retracted fully within their housings, unlatching the pivotally connected link segments and allowing them to pivot relative to each other from extended, operative positions to retracted, inoperative positions to permit a coupled implement to be uncoupled from the dipper stick. The axial dimension of each latch member prevents the displacement of an associated piston member from extending beyond the opening in which such piston member is disposed to prevent the latching of the adjoining link segments when the latch member thereof is fully retracted. 
     FIGS. 5,  5 A and  5 B illustrate a further alternate coupling assembly  90  embodying the present invention. The assembly includes a set of spaced, parallel connecting pins  91  and  92  comparable in construction and operation to connecting pins  13  and  31 , a pair of spacer links  93  and  94  comparable to spacer links  53  and  54  and a pair of latch mechanisms  95  and  96  comparable to latch mechanisms  58  and  59  with the exception of the means provided for displacing the latch member. Latch members  95  and  96  are essentially the same in construction and operation. Referring to FIGS. 5A and 5B, latch mechanism  95  includes a housing  97  rigidly secured to a link segment  98  overlying a circular opening  99  in such segment and a housing  99  rigidly mounted on link segment  100  overlying a circular opening  101  therein adapted to register with opening  99  when the assembly is in its extended, operative condition as shown in FIG.  5 . Housings  97  and  99  are provided with registrable, cylindrical guide sleeves  102  and  103  in which there is provided an axially displaceable latch member  104 . As in the previously described embodiment, latch member  104  is provided with an axially disposed guide pin  105  disposed within and extendable beyond an opening in an end wall of housing  95  and a coil spring  106  operable to displace the latch member into a registered guide sleeve  103  as shown in FIG. 5A, and compressable to allow the latch member to be displace entirely within guide sleeve  102  and thus permit the link segments to angularly displace relative to each other. The latch member is caused to displace axially to a retracted position within guide sleeve  102  against the biasing action of spring  106  by means of a cam device  107  provided on housing  99  within guide sleeve  103 . The device consists of a bolt  108  having a shank portion  109  extending through an opening in an upper wall of housing  99  and aligned openings in guide sleeve  103 , and threaded into an opening in a bottom wall of the housing, and a head portion  110  disposed on the exterior of the housing. Rigidly connected to the shank portion of bolt  108 , within guide sleeve  103 , is a cam element  111  which is adapted to be engaged by an end wall surface  112  of latch member  104 . Cam element  103  has a circular configuration and is econtrically mounted relative to the axis of shank portion  109  so that upon rotating bolt  108  about its axis, the latch member biased into engagement with the cam element will be caused to displace axially into a latching position as shown in FIG.  5 A and an unlatched position as shown in FIG.  5 B. Typically, the cam device will be rotated to latch and unlatch the link segments merely by applying a tool to the head portion of the device and rotating it. In addition to providing a manually operable camming device as shown in FIGS. 5,  5 A and  5 B, such device may be provided with a small motor mounted on housing  99  which can be operated from a remote site such as the operators station on the machine. As best illustrated in FIG. 5B, the axial dimension of the latch member is made the same as the axial dimension of guide sleeve  102  so that when the latch member is fully retracted against the biasing action of the spring, cam element  111  will be precluded from entering guide sleeve  102  and thus provide, an obstruction preventing the link segments to be angularly displaced relative to each other. 
     In each of the embodiments as described, various additional features may be included to facilitate and enhance the operations of the coupling assemblies. As previously mentioned, spacer bushings may be provided on the ends of the connecting pins to center the coupling assemblies, adapt them to different dipper stick sizes and accommodate different pin receiving openings in the mounting brackets of implements to be coupled. The connecting pins mounted on the dipper stick may be rigidly connected to one set of link segments as described and pivotally connected to the dipper stick or pivotally connected to such link segments and rigidly connected to the dipper stick. Similarly, the connecting pins connected to the actuating links may be rigidly connected to a set of link segments and pivotally connected to the actuating links as described or pivotally connected to such link segments and rigidly connected to the actuating links. To prevent the sets of links segments from freely, angularly displacing relative to each other, the pivot bolts therefore may be provided with Bellville washers to retard any free angular displacement. In lieu of a manually operable arrangement as shown in FIGS. 1 through 3, remotely operable latch and unlatching devices may be provided as shown in FIGS. 4 through 5A. Such remotely operated arrangements may be either electrically, hydraulically or pneumatically actuated. 
     It further will be appreciated that the present invention provides an arrangement whereby a conventional excavating machine and a plurality of conventional implements including buckets, grapples, racks and the like may be easily and inexpensively modified to permit such machine to easily couple and uncouple a variety of implements. Such arrangement involves not only simple modifications of the machine dipper stick and the implements to be coupled to the machine but the addition of a few, simple components. 
     From the foregoing detailed description, it will be evident that there are a number of changes, adaptations and modifications of the present invention which come within the province of those persons having ordinary skill in the art to which the aforementioned invention pertains. However, it is intended that all such variations not departing from the spirit of the invention be considered as within the scope thereof as limited solely by the appended claims.