Abstract:
An attachment device for releasably securing an implement such as a bucket, pallet fork, etc., to the arms of an end loader includes a self-contained latching mechanism. The latching mechanism extends between the arms and has a first upper U-shaped support groove and a lower slot for receiving and engaging respective upper and lower elongated mounting pins of the implement. A linearly movable latch pin, or plunger, is disposed adjacent the lower slot for locking the implement&#39;s lower mounting pin in position within the slot in attaching the implement to the end loader. The latch pin also undergoes a pivoting motion during mounting pin insertion and removal to allow for automatic implement attachment to and disconnection from the end loader without the end loader operator having to leave the end loader and manually tend to the attachment device.

Description:
FIELD OF THE INVENTION 
   This invention relates generally to end loaders and attachments therefor, and is particularly directed to a quick attachment arrangement for allowing a first unlatched implement such as a bucket, sweeper, pallet fork, etc., to be removed from an end loader and a second replacement implement to be securely attached to the end loader without requiring the operator to leave the operating position on the end loader and manually tend to the attachment arrangement. This invention also allows an implement to be automatically attached to the end loader without operator manual intervention whether the latching mechanism is in the closed, latched configuration or the open, unlatched configuration. 
   BACKGROUND OF THE INVENTION 
   End loaders are commonly used for performing various industrial and agricultural tasks. The typical end loader is comprised of a vehicle, such as a tractor, having a pair of flexible arms typically extending from the front end of the vehicle, where the arms can be raised and lowered for performing work. Various types of implements may be attached to the ends of the arms for performing such tasks as lifting, sweeping, digging, grading, etc. Thus, the implement attached to the end loader may take the form of a scoop or a fork structure for lifting and transporting an object or loose material such as dirt or stone, a sweeper for cleaning a surface, or a grader for working the ground. In virtually all cases, the load bearing or load moving implement is of high strength and is typically comprised of a strong metal such as steel and is thus of considerable weight. 
   Because the various implements discussed above are designed to perform a specific task, it is necessary to change implements when the performance of various tasks is required. It is thus highly desirable to facilitate and simplify the removal of one implement from and the attachment of another implement to the end loader&#39;s movable arms. Unfortunately, there is a great variety of lift arm attachment arrangements, where the specific design of the attachment arrangement is determined by the individual implement or end loader manufacturer. Some end loader attachment arrangements make use of a pair of vertically spaced, horizontally aligned mounting pins which are adapted for engagement by upper and lower pairs of grooves, or slots, on the ends of the end loader arms. Another attachment scheme makes use of left and right brackets, each adapted to receive a generally vertically oriented connecting pin for attaching the implement to the ends of the end loader&#39;s two lift arms. The various attachment arrangements incorporate different connecting hardware and employ different installation and removal procedures in attaching and releasing the implement from the end loader and are thus incompatible. 
   A typical attachment device used for attaching an implement to a pair of end loader arms typically has a first side adapted for connection to the ends of the end loader arms and a second, opposed side for connecting to the implement. In some cases, part of the attachment arrangement is incorporated in the attachment device, while another part of the attachment arrangement is mounted integrally with the implement. For example, U.S. Pat. No. 4,986,722 discloses an implement attachment arrangement having a first locking pin  106  disposed on one end of a bucket  50  which is adapted for engaging an attachment carrier  30  mounted to an end of the end loader&#39;s moveable arm  22 . Also attached to the movable arm  22  is an actuator mechanism having contact pin  122  which engages a handle  118  of locking pin  106  for moving the pin to a locking position as the attachment is rocked about a pivotal axis by an attachment cylinder. This complicated arrangement requires mutually engaging components of the latching mechanism on the implement as well as on the end loader. Preferably, the entire latching mechanism would be located on either the implement or the end loader to simplify its design and eliminate the requirement for precise alignment of the implement and loader arms for attaching/detaching the implement. 
   The latching mechanism also typically requires manual intervention by the end loader operator in releasing an implement from or attaching an implement to the end loader&#39;s arms. More specifically, the end loader operator must set the latch mechanism to a release configuration for disconnection of the implement from the end loader or set the latch mechanism to an engagement configuration for attaching the implement to the end loader. This requires the end loader operator to leave the operating position on the end loader twice in changing the implement attached to the end loader, once to disconnect the implement to be released and a second time to connect a replacement implement. This procedure is inefficient and subjects the operator to possible injury during implement release from or attachment to the end loader&#39;s arms. In addition, the operator&#39;s manual intervention in the attachment procedure raises the possibility of subsequent implement detachment due to human error. 
   The present invention addresses the aforementioned limitations of the prior art by providing an attachment arrangement for mounting an implement to the arms of an end loader which is self-contained on the end loader arms and requires only a pair of fixed, spaced, parallel mounting pins on the implement. This inventive quick attachment arrangement allows an implement to be attached to the end loader&#39;s arms regardless of the configuration of the latching mechanism, and the implement may be removed and replaced with another implement attached to the arms without requiring the end loader operator to leave the operating position for the purpose of manually manipulating the latching mechanism. 
   OBJECTS AND SUMMARY OF THE INVENTION 
   Accordingly, it is an object of the present invention to provide an improved arrangement for connecting an implement to the arms of an end loader which is reliable, self-contained on the ends of the end loader arms, and does not require the end loader operator to leave the operator&#39;s seat to change implements. 
   It is another object of the present invention to provide a latching mechanism for removably mounting an implement to the ends of a pair of end loader arms which does not require manual intervention by the end loader operator. 
   Yet another object of the present invention is to provide a quick attachment device for attaching an implement to an end loader which is self-contained and includes no moving parts on either the implement or the arms of the end loader. 
   A further object of the present invention is to provide a connection arrangement for an implement on the end of a pair of boom arms such as on an end loader which employs a pair of latching pins which undergo linear displacement along their respective lengths as well as pivoting displacement in latching the implement to, as well as unlatching the implement from, the boom arms. 
   This invention contemplates apparatus for attaching an implement having upper and lower mounting pins to a movable arm of an end loader, the apparatus comprising: a bracket pivotally coupled to the movable arm; an upper support member on the bracket adapted to engage and retain the upper mounting pin of the implement; a lower slot in the bracket adapted to receive the lower mounting pin of the implement; first and second apertured members disposed on the bracket; a latch pin disposed in the apertures of the first and second apertured members and movable between a first unlatched position, wherein the latch pin is substantially clear of the lower slot and the lower mounting pin may be removed from the lower slot, and a second latched position, wherein the latch pin is disposed across the lower slot and the lower mounting pin is connected to the bracket for attaching the implement to the end loader arm; a biasing member coupled to the latch pin for urging the latch pin to the second latched position; and a catch portion of the latch pin for engaging the first apertured member and maintaining the latch pin in the first unlatched position to allow the lower mounting pin to be removed from the lower slot as the lower mounting pin engages and pivotally displaces the latch pin in a first direction for maintaining the latch pin&#39;s catch portion in engagement with the first apertured member, and wherein a second lower mounting pin attached to a second implement inserted in the lower slot engages and pivotally displaces the latch pin in a second opposed direction for removing the latch pin&#39;s catch portion from engagement with the first apertured member and allowing the latch pin to move to the second latched position by means of the biasing member in attaching the second implement to the end loader. 
   This invention further contemplates apparatus for attaching an implement having upper and lower mounting pins to a movable arm of a vehicle, the apparatus comprising: a bracket pivotally coupled to the movable arm; upper and lower slots in the bracket respectively adapted to engage and retain the upper and lower mounting pins; first and second apertured members disposed on the bracket; a latch pin having an angled distal end portion and disposed in the apertures of the first and second apertured members and movable between a first unlatched position, wherein the latch pin is clear of the lower slot allowing the lower mounting pin to be removed from the lower slot, and a second latched position, wherein the latch pin is disposed across the lower slot and the lower mounting pin is connected to the bracket for attaching the implement to the end loader arm; a biasing member coupled to the latch pin for urging the latch pin to the second latched position; and a catch portion of the latch pin for engaging the first apertured member and maintaining the latch pin in the first unlatched position to allow the lower mounting pin to be inserted in and removed from the lower slot, wherein the lower mounting pin engages the end of the latch pin when inserted in the lower slot with the latch pin in the first unlatched position for pivotally displacing the latch pin and removing the latch pin&#39;s catch portion from engagement with the first apertured member and allowing the latch pin to move to the second latched position under the influence of the biasing member for attaching the implement to the end loader, and wherein the lower mounting pin engages the angled distal end portion of the latch pin when inserted in the lower slot and the latch pin is in the second latched position for urging the latch pin to the first unlatched position and allowing the lower mounting pin to be inserted in the lower slot whereupon the lower mounting pin pivotally displaces the latch pin so as to disengage the latch pin&#39;s catch portion from the first aperture member allowing the latch pin to assume the second latched position in attaching the implement to the end loader. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The appended claims set forth those novel features which characterize the invention. However, the invention itself, as well as further objects and advantages thereof, will best be understood by reference to the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings, where like reference characters identify like elements throughout the various figures, in which: 
       FIG. 1  is a side elevation view showing a bucket implement attached to an arm such as of an end loader by means of an attachment device in accordance with the principles of the present invention; 
       FIGS. 2–5  are vertical sectional views of the attachment device of the present invention illustrating the position of various components of the attachment device during insertion in and removal from the attachment device of an implement mounting pin, and further illustrating the attachment device in the unlatched and latched configurations; 
       FIGS. 6 ,  7  and  8  are vertical sectional views illustrating the series of steps involved in attaching an implement to the attachment device of the present invention with the attachment device&#39;s latching pin, or plunger, in the up, unlatched position; 
       FIGS. 9 ,  10  and  11  are vertical sectional views illustrating the series of steps involved in attaching an implement to the attachment device of the present invention with the attachment device&#39;s latching pin the down, latched position; 
       FIGS. 12 ,  13  and  14  are vertical sectional views illustrating the series of steps involved in detaching an implement from the attachment device of the present invention; and 
       FIGS. 15 ,  16  and  17  are respectively top plan, front elevation and side elevation views of a second embodiment of a quick attachment arrangement in accordance with the principles of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIG. 1 , there is shown a side elevation view of an implement such as a bucket  28  connected to a loader arm  22  such as of an end loader by means of a quick attachment arrangement  20  in accordance with the principles of the present invention. Attached to an aft portion of the bucket  28  is a mounting bracket  34 . Attached to the loader arm  22  is a hydraulic cylinder  24  for raising and lowering the loader arm as well as the bucket  28  attached thereto. The attachment device  26  of the present invention is attached to the hydraulic cylinder  24  and the loader arm  22  by means of respective first upper and lower mounting pins  30   a  and  30   b . A second, opposed portion of the attachment device  26  is connected to the bucket mounting bracket  34  by means of second upper and lower mounting pins  32   a  and  32   b.    
   Referring to  FIGS. 2–5 , there are shown vertical sectional views of a quick attachment arrangement  20  including an attachment device  26  in accordance with the present invention illustrating the attachment device configuration when being attached to, and when removed from, a mounting pin of an implement. Referring to  FIGS. 6 ,  7  and  8 , there are shown vertical sectional views of the quick attachment arrangement  20  of the present invention illustrating the series of steps involved in engagement of the attachment device  26  with a bucket  28  with the latch pin, or plunger,  40  in the up, or retracted, position. Referring to  FIGS. 9 ,  10  and  11 , there are shown vertical sectional views of the quick attachment arrangement  20  of the present invention illustrating the series of steps involved in engagement of the attachment device  26  with bucket  28  with latch pin  40  in the down, or extended, position. Referring to  FIGS. 12 ,  13  and  14 , there are shown vertical sectional views of the quick attachment arrangement  20  of the present invention illustrating the disengagement sequence of attachment device  26  from bucket  28 . The configuration and operation of the quick attachment arrangement  20  shown in these figures will now be described in detail. 
   The attachment device  26  of the quick attachment arrangement  20  of the present invention includes a plate  27  which is pivotally connected to and through which extend first upper and lower mounting pins  30   a  and  30   b . The attachment device  26  may also include a second plate (not shown) in spaced relation from plate  27 , with the first upper and lower mounting pins  30   a ,  30   b  connected to and extending between the two spaced, generally parallel plates. Each of the first upper and lower mounting pins  30   a ,  30   b  is connected to an aft portion of the attachment device&#39;s plate  27 . A forward portion of the attachment device  26  includes an upper U-shaped support groove, or surface,  36  and a lower slot  38 , each of which is integrally formed with the attachment device&#39;s plate  27 . Attachment device  26  further includes an upper catch plate  42  and a lower guide plate  44  mounted to the attachment device&#39;s plate  27 . Catch plate  42  and guide plate  44  are in vertical alignment and each includes a respective aperture within which is positioned an elongated latch pin, or plunger,  40 . Also attached to the attachment device&#39;s plate  27  is a face plate  52  which is in contact with the lower guide pin  44  and engages a lower end portion of latch pin  40 . Latch pin  40  includes a notch  40   b  in the surface thereof and an angled end portion  40   a  on the lower end thereof. The latch pin&#39;s notch  40   b  is adapted to engage an inner edge portion of the upper catch plate  42  where the catch plate&#39;s inner edge defines the aperture through which the latch pin extends. The latch pin&#39;s angled end portion  40   a  is adapted to engage a bottom mounting pin  32   b  when attaching the attachment device  26  to an implement as described in detail below. 
   As shown in  FIG. 6 , attachment device  26  is initially maneuvered so as to position the upper mounting pin  32   a  of the bucket  28  within the upper U-shaped support groove  36  located within an upper portion of the attachment device&#39;s plate  27 . This is accomplished by orienting the attachment device  26  at an inclined angle and raising the attachment device in the direction of arrow  25  shown in  FIG. 6 . The lower portion of the attachment device  26  is then moved toward the bucket  28  in the direction of arrow  56  shown in  FIGS. 7 and 8  so as to position the bucket&#39;s second lower mounting pin  32   b  within the attachment device&#39;s lower slot  38  as shown in  FIG. 8 . Latch pin  40  is shown in  FIGS. 6 and 7  in the raised position to allow the bucket&#39;s second lower mounting pin  32   b  to be inserted in the attachment device&#39;s lower slot  38 . However, the attachment device  26  is also adapted to receive the bucket&#39;s second lower mounting pin  32   b  within its lower slot  38  with latch pin  40  in the lowered position as described in detail below. 
   As shown in the various figures, a coil spring  46  is disposed about and attached to latch pin  40 . Coil spring  46  engages and is disposed between the upper catch plate  42  and a roll pin  43  inserted through latch pin  40 . Coil spring  46  urges latch pin  40  downward to the latched position wherein the lower end of the latch pin extends across lower slot  38  in plate  27 . As stated above, notch  40   b  in latch pin  40  is adapted to engage an inner surface of upper catch plate  42 . In this manner, latch pin  40  may be securely maintained in a retracted, upraised position even while being urged in a downward direction by coil spring  46 . In the upraised position, latch pin  40  does not extend across lower slot  38  within the attachment device&#39;s plate  27 . When in the upraised, retracted position as shown in  FIGS. 6 and 7 , only the lower end of latch pin  40  extends into an upper portion of the attachment device&#39;s slot  38 . Latch pin  40  may be moved to the full down, extended position by expansion of coil spring  46  by laterally displacing the latch pin so that its catch notch  40   b  is no longer in engagement with the upper catch plate  42 . Latch pin  40  may be laterally displaced so as to no longer engage catch plate  42  by engagement of the lower end of the latch pin by the bucket&#39;s second lower mounting pin  32   b  during automatic operation of quick attachment arrangement  20  as described in the following paragraph. 
   In accordance with automatic operation of the quick disconnect arrangement  20  of the present invention, the bucket&#39;s second lower mounting pin  32   b  is moved in the direction of arrow  29  in  FIG. 2  and into the attachment device&#39;s lower slot  38 . When this occurs, the second lower mounting pin  32   b  engages the lower end of latch pin  40  forcing a lower portion of the latch pin into engagement with a pivot point  44   a  on an inner surface of the lower guide plate  44  defining the aperture therein. With the lower end of pivot pin  40  displaced in the direction of arrow  29  in  FIG. 2 , the upper portion of the pivot pin is pivotally displaced about the pivot point  44   a  in a second direction opposed to that of arrow  29 . It is in this manner that the catch notch  40   b  of pivot pin  40  becomes disengaged from catch plate  42  as shown in  FIG. 2 , allowing coil spring  46  to urge pivot pin  40  downward across the lower slot  38  within the attachment device  26  as shown in  FIG. 4 . It is in this manner that the attachment device  26  is automatically connected to an implement such as bucket  28  with latch pin  40  initially in the unlatched position without requiring manual intervention by the end loader operator or anyone else. This sequence of automatic operation of the attachment device  26  is also shown in  FIGS. 6 ,  7  and  8 . 
   Bucket  28  may also be automatically connected to attachment device  26  with latch pin  40  initially in the full down position as shown in  FIGS. 9 ,  10  and  11 . In this configuration, latch pin  40  is in the full down position prior to connecting bucket  28  to attachment device  26  as shown in  FIG. 9 . As the lower portion of the attachment device  26  is displaced in the direction of arrow  51  in  FIG. 9  toward bucket  28  with the bucket&#39;s second upper mounting pin  32   a  disposed within the attachment device&#39;s upper U-shaped support groove  36 , the bucket&#39;s second lower mounting pin  32   b  engages the latch pin&#39;s angled lower end portion  40   a  as shown in  FIG. 10 . Continued displacement of the second lower mounting pin  32   b  into lower slot  38  causes upward displacement of latch pin  40 . In addition, the force exerted on the lower end of latch pin  40  by the second lower mounting pin  32   b  causes pivoting displacement of the latch pin about pivot point  44   a  on lower guide plate  44 . This causes the lower end of latch pin  40  to move in a direction opposite to that of arrow  51  in  FIG. 9  and the upper portion of the latch pin to move in the direction of this arrow. This causes the latch pin&#39;s catch notch  40   b  to be displaced away from the inner portion of catch plate  42  defining the aperture therein so that the latch pin is freely slidable within the upper catch plate  42 . This allows latch pin  40  to be displaced downward under the influence of coil spring  46  and to assume the full down position after insertion of the second lower mounting pin  32   b  within lower slot  38  as shown in  FIG. 11 . It is in this manner that latch pin  40  assumes the latched configuration even when the latch pin is in the fully extended, or down, position prior to insertion of the second lower mounting pin  32   b  in lower slot  38 . 
   Referring to  FIGS. 12 ,  13  and  14 , there is shown the disengagement sequence for disconnecting bucket  28  from attachment device  26 . In  FIG. 12 , latch pin  40  is shown in the full up, unlatched position. This is achieved by manually engaging handle  48  connected to latch pin  40  by nut and bolt combinations  50   a ,  50   b  and moving the handle in the direction of arrow  45  in  FIG. 12 . Thus, handle  48  and latch pin  40  are displaced upward and to the right as shown in  FIG. 12  causing the latch pin&#39;s catch notch  40   b  to engage the inner surface of catch plate  42  so as to maintain latch pin in the upraised, unlatched position shown in  FIG. 12 . The lower portion of attachment device  26  is then displaced in the direction of arrow  47  by moving end loader arm  22  in a rightward direction as shown in  FIG. 13 . This causes the bucket&#39;s second lower mounting pin  32   b  to be removed from the attachment device&#39;s lower slot  38  as shown in  FIGS. 12 and 13 . As the bucket&#39;s second lower mounting pin  32   b  is removed from the attachment device&#39;s lower slot  38 , the second lower mounting pin engages the lower end of latch pin  40  causing the latch pin to pivot about pivot point  44   b  in the lower guide plate  44 . Latch pin  40  may also partially engage a face plate  52  attached to plate  27  and pivot about a point of contact between the latch pin and the face plate. This urges the upper end of latch pin  40  in the direction of arrow  47  in  FIG. 13  so as to maintain the latch pin&#39;s catch notch  40   b  in engagement with the catch plate  42  to maintain the latch pin in the fully upraised, unlatched position shown in  FIG. 13 . While lower guide plate  44  and face plate  52  are shown as separate elements in the various figures, they may equally as well be in the form of a single piece of hard, high strength metal such as steel which is the preferred composition of the entire inventive quick attachment arrangement. The attachment device  26  is then lowered in the direction of arrow  49  shown in  FIG. 14  by end loader arm  22  to disconnect bucket  28  from the attachment device  26 . With latch pin  40  in the fully upraised, unlatched position, the attachment device  26  is then ready for connection to another implement without requiring manual intervention or reconfiguration of the quick attachment arrangement of the present invention. 
   Referring to  FIGS. 15 ,  16  and  17 , there are respectively shown top plan, front elevation and side elevation views of a quick attachment arrangement  60  in accordance with another embodiment of the present invention. Quick attachment arrangement  60  includes a mounting bracket  62  to which are attached a top guide plate  64  and a bottom guide plate  65 . Mounting bracket  62  is adapted for attachment to an arm of an end loader (not shown for simplicity) by means of plural bolt  72  and nut  74  combinations. Each of the top and bottom guide plates  64 ,  65  includes a respective aperture, with the apertures in each of these guide plates in vertical alignment. Disposed within the vertically aligned apertures of the top and bottom guide plates  64 , 65  is a movable latch pin, or plunger,  63 . Inserted through latch pin  63  is a roll pin  69 . Disposed about latch pin  63  and between the top guide plate  64  and roll pin  69  is a coil spring  70  which is shown in simplified dotted line form in  FIGS. 16 and 17 . Coil spring  70  urges latch pin  63  in a downward direction as viewed in  FIGS. 16 and 17  so that the latch pin assumes the latching position as shown in  FIG. 17 . Latch pin  63  may be manually raised upward by means of a handle  68  so as to assume the unlatched position wherein the latched pin is clear of a slot  62   a  in a lower portion of mounting bracket  62 . Latch pin  63  may be maintained in the retracted, unlatched position by engaging a notch  63   a  in a lateral surface of the latch pin with an inner portion of the top guide plate  64  defining the aperture therein as in the previously described embodiment. 
   Slot  62   a  within mounting bracket  62  is adapted to receive a mounting pin  76  attached to an implement, such as the previously described bucket; for attaching the bucket to the arms of an end loader by means of the inventive quick attachment arrangement  60 . A back stop  66  in the form of a 90° bent section of steel is attached to a lateral surface of mounting bracket  62  adjacent the inner end of slot  62   a  in the bracket. Back stop  66  engages a lateral portion of a mounting pin  76  attached to an implement (not shown for simplicity) inserted in slot  62   a  for maintaining the mounting pin securely in position in the slot of mounting bracket  62 . The lower end of latch pin  63  includes first and second beveled portions  63   b  and  63   c . An upper portion of mounting pin  76  includes a beveled corner  76   a  which is adapted for engaging the latch pin&#39;s shorter first beveled end portion  63   b  when inserting mounting pin  76  into slot  62   a . The engagement of the mounting pin&#39;s beveled corner  76   a  with the latch pin&#39;s shorter first beveled end portion  63   a  facilitates rightward movement of mounting pin  76  and upward displacement of latch pin  63  for connecting the mounting pin to mounting bracket  62 . Engagement of the rounded upper corner  76   b  of mounting pin  76  with the longer second beveled end portion  63   b  of mounting pin  63  facilitates leftward displacement of the mounting pin and upward movement of the latch pin  76  for disconnecting the mounting pin from mounting bracket  62 . 
   While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the relevant arts that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. The present invention is thus intended to provide a quick attachment arrangement between an end loader and virtually any type of load bearing or work performing implement with which end loaders operate. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.