Abstract:
The disclosure describes, in one aspect, a powered guard group for a machine, the guard group including a frame, a linkage, two doors, an actuator cylinder, and a cam disc mechanism with two actuator arms for moving the guard group between an open position and a closed position and the ways to access them.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates generally to a guard group for a machine and more particularly to a powered bottom guard group to protect and provide service access to the underside and/or mechanical components of the machine. 
       BACKGROUND 
       [0002]    Work machines, such as track-type tractors, utilize various types of guards to protect vulnerable portions of the machine. One particular type of guard is a bottom guard which is secured to the bottom of a work machine to protect portions of the engine, transmissions, or other vital machine components. This type of guard is generally assembled to the frame of the machine. In order to sufficiently protect the bottom and components of the work machine from impacts with objects such as rocks, stumps, soil and debris, the guards must have adequate structural integrity, high yield strength and adequate wear properties. The size and material requirements of the guards make the guard large and heavy, which make the guards difficult to remove during maintenance or repair event. In addition, work machines are often used in a range of conditions such as muddy conditions which can result in excessive debris accumulation on the guards and make it difficult to access the guards. The additional weight of the debris makes the guards even heavier. 
         [0003]    One example of a bottom guard is illustrated in U.S. Pat. No. 4,957,180, titled Guard Assembly for a Vehicle. The &#39;180 Patent discloses a guard assembly for protecting the lower portions of an earthmoving machine which protect critical components and systems, such as the engine, transmission and drive train. The guard assembly includes a guard plate fastened to the machine frame using threaded fasteners. 
         [0004]    The foregoing background discussion is intended solely to aid the reader. It is not intended to limit the disclosure, and thus should not be taken to indicate that any particular element of a prior system is unsuitable for use within the disclosure, nor is it intended to indicate that any element, including solving the motivating problem, is essential in implementing the systems and methods described herein. The implementations and application of the systems and methods described herein are defined by the appended claims. 
       SUMMARY OF THE INVENTION 
       [0005]    The disclosure describes, in one aspect, a guard group assembled to the frame of a work machine including a door having an inner side, an outer side, a first edge and a second edge, the first edge being opposite of the second edge, the door being configured to move between a closed position and an open through two actuator aims moving around a cam disc coupled with the actuator. In addition, the guard group includes a frame coupled to the linkage, the frame having at least two stiffeners, the stiffeners being configured to contact the inner side and inhibit the door from moving when the door is in the closed position and is contacted by a rock, stump or the like; and an actuator linked with actuator arm and cam disc, the actuator cylinder piston extends or retracts which rotates the cam disc and in turn pushes or pulls the two actuator arms to move the doors between the open and closed positions. 
         [0006]    In another aspect, the disclosure describes a guard group for a machine including a first door movable between a closed position and an open position, the first door being configured to inhibit rocks, branches and the like from striking a mechanical component when the first door is in the closed position and a second door movable between a closed position and an open position, the second door being configured to inhibit rocks, branches and the like from striking a mechanical component when the second door is in the closed position. The guard group also includes two actuator arms and cam disc coupled to the first door, a similar set of two actuator arms and cam disc coupled to the second door, a first actuator coupled to the first linkage, the first power actuator being configured to move the first door between the closed position and the open position through the actuator arm and cam arrangement; and a second actuator coupled to the second linkage, the second power actuator being configured to move the second door between the closed position and the open position through the actuator arm and cam arrangement. 
         [0007]    In yet another aspect the disclosure describes a machine having a chassis, a work implement coupled to the chassis, a prime mover coupled to the chassis, a first and second track assembly powered by the prime mover and configured to selectively move the machine; and a guard group coupled to the chassis. The guard group includes a first guard mounting surface coupled to the chassis, a second guard mounting surface, a first stiffener and a second stiffener coupled to the first guard mounting surface and the second guard mounting surface, a linkage coupled to the first guard mounting surface, a door coupled to the linkage, the door being configured to move between a closed position and an open position and an actuator coupled to the linkage, the actuator being configured to move the door between the closed position and the open position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a side view of a machine which may incorporate a bottom guard group assembly according to the present disclosure. 
           [0009]      FIG. 2  is a perspective view of a housing and chassis for a machine shown in  FIG. 1 , showing first and second guard groups of a guard assembly according to the present disclosure with cam discs, actuator arms and doors in an open position. 
           [0010]      FIG. 3  is an end view of the guard assembly of  FIG. 2  with the doors of first and second guard groups in an open position. 
           [0011]      FIG. 4  is a perspective view of the guard assembly of  FIG. 2  showing the first and second guard groups in a closed position. 
           [0012]      FIG. 5  is a perspective view of the guard assembly of  FIG. 2  showing the first and second guard groups in an open position. 
           [0013]      FIG. 6  is an end view of the housing and chassis of  FIG. 2 , showing the first guard group in a closed position; and 
           [0014]      FIG. 7  is an end view of the housing and chassis of  FIG. 2 , showing the first guard group in an open position. 
           [0015]      FIG. 8  is a side view of the guard group with the doors showing the position of the stopper when the doors are in closed position. 
           [0016]      FIG. 9  is a side view of the guard group with the doors showing the position of the stopper when the doors are in open position. 
           [0017]      FIG. 10  is a bottom view of the bottom portion of the guard group which shows the doors of the guard assembly in closed and bolted position. 
           [0018]      FIG. 11  is a side view of the guard group with the guard assembly suspended on a hinge attached to the frame. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Referring now to  FIG. 1 , a machine  10  is a track-type tractor, however the present disclosure guard assembly is not limited to track-type tractors and is applicable to other machines such as off highway trucks, skid steer machines, backhoe loaders, landfill compactors, shovels, excavators, motor graders, wheel loaders and the like. The machine  10  includes a chassis  14 , a first work implement  18 , a second work implement  22 , a prime mover  30 , two track assemblies  26  and a guard assembly  38  ( FIG. 2 ). The work implement  18  may be a blade and the second work implement  22  may be a ripper coupled to the chassis  14  as is customary. The prime mover  30  may be an internal combustion engine which is supported by the chassis  14  ( FIG. 2 ). The two track assemblies  26  (the left track not shown) are powered by the prime mover  30  and a transmission (not shown) is connected to the prime mover  30  to allow the operator to selectively move the machine  10 . As best seen in  FIG. 2 , the guard assembly  42  allows service personnel to access the prime mover  30 , torque converter (not shown), driveshaft (not shown) and is coupled to the chassis  14  as is described in further detail below. 
         [0020]    The guard group  38  will now be described. As best shown in  FIGS. 2 and 4 , the guard group  38  is attached to an underside of the machine  10  ( FIG. 1 ) and is positioned approximately in a center portion of the underside of the machine  10 . The guard group  38  includes two actuatable guard assemblies, namely, front guard assembly  42   a  and rear guard assembly  42   b . Since guard assemblies  42   a  and  42   b  are substantially similar—except rear guard assembly  42   b  covers a larger opening—the front guard assembly  42   a  will first be described and any difference in the rear guard assembly  42   b  will be noted. The front guard assembly  42   a  includes a frame  34   a , two doors  50   a , four linkages  54 , an actuator cylinder  58 , first actuator arm  114 , second actuator arm  118  and a cam disc  110 . 
         [0021]    The frame  34   a , as best shown in  FIG. 4 , includes a guard mounting portion  62   a , a plurality of stiffeners  70  and a cross-member  74   a . The guard mounting portion  62   a  is sized and configured to allow the frame  34   a  to be attached to the chassis  14  of the machine  10  ( FIG. 1 ). The guard mounting portion  62   a  may be coupled to the chassis  14  by welding, fasteners or the like. As best seen in  FIG. 7 , the guard mounting portion  62   a  and the chassis  14  are bolted together with bolts  102  ( FIG. 4 ). The first guard mounting portion  62   a  is contoured to match the contour of the chassis  14 . The plurality of stiffeners  70  extend along the U-shaped contour of the front frame  34   a  to help provide support to the front frame  34   a . Regarding the general construct of the rear frame  34   b , three stiffeners  70  extend along the U-shaped portion of this frame  34   b  to stiffen the frame and provide a solid foundation for the door  50   b , actuator  58  and linkage  114 ,  118  assemblies. Each cross-member  74   b  of the rear guard assembly  42   b , longitudinally extends along the centerline of the guard assembly  42   b  and interacts with the three stiffeners  70  to provide a solid under-belly structure to rigidly support and protect doors  50   b . As can be seen in  FIG. 4 , the cross-members  74   b  are disposed approximately in the center of the guard assembly  42   b and are rigidly attached at ends thereof to the plurality of stiffeners  70  at center-end portions  78   b  of each of the plurality of stiffeners  70 . The cross-members  74   b  includes threaded openings  82  to receive the door bolts  134  which allow the doors  50   b  to be secured to the cross-members  74  via the fasteners coinciding with a locked condition of doors—typically locked during machine operation, for example. Similarly, the front guard assembly  42   a  has a similar construct relative to the rear guard assembly  42   b , however due to the shorter span only one cross-member  74   a  is required. 
         [0022]    The front guard assembly  42   a  includes two doors  50   a , although it is contemplated that a single door may also be used. Each door  50   a  includes an inner side  86   a , an outer side  90   a , a first edge  94   a  and a second edge  98   a . The first edge  94   a  is disposed opposite of the second edge  98   a . The door  50   a  is configured to pivot between a closed position ( FIG. 6 ) and an open position ( FIG. 7 ). In the illustrated embodiment the door  50   a  is contoured in an L-shaped configuration to match the contour of the frame  34   a . Each door  50   a  also includes threaded openings  82  which allow the door bolts  134  to pass through and engage with the four threaded openings  82  within the cross-member  74   a . In this manner, the doors  50   a  may be left closed in the machine operational state and then actuated to the open position in preparation for a service event. 
         [0023]    Referring to  FIGS. 4 and 5 , the linkage assembly  54  will now be described. The guard assemblies  42   a ,  42   b  each include four linkages  54 . Each linkage  54  is substantially similar, so only the linkage  54  relative to the front guard assembly  42   a  will be described. The linkage  54  is attached to the door  50   a  on a first end and is pivotally attached to the frame  34   a  to allow the linkage  54  to rotate with respect to the frame  34   a . The linkage  54  is approximately in the shape of a “C”, and in an exemplary embodiment, two linkages  54  are attached to each door  50   a . As is best seen in  FIG. 5 , each linkage  54  serves to support the door  50   a  when the front guard assembly  42   a  is in the open position. The linkage  54  also supports each door  50   a  when the front guard assembly  38  is in the open position ( FIG. 3 ). 
         [0024]    Referring to  FIG. 3 , the actuator cylinder  58  will now be described. The actuator cylinder has a rod end which is attached to the linkage  54  and, in turn, the linkage  54  is attached to the door  50   a . The first actuator arm  114  has a first end attached to the door  50   a  and a second end which is attached to a cam disc  110  and as the rod of the actuator cylinder  58  is moved the door  50   a  and first actuator arm  114  is moved. As the cam disc  110  is urged to rotate by the actuator arm  114  the second actuator arm  118  is urged to rotate. The other end of the second actuator arm is attached to the other door  50   a  and therefore the door is urged to move through the second actuator arm  118  based on movement of the cam disc  110 . In an exemplary embodiment the actuator cylinder  58  has its rod end attached by a pin and u-clip join on the door  50   a  and its cylinder end is attached to the frame  34  which is secured to the chassis  14 . The actuator cylinder  58  serves to move one of the doors  50   a  which in turn moves the other door contemporaneously via the cam disc  110  and linkage arms  114 ,  118 . The actuator cylinder  58  is structured and arranged to position each of the front and rear guard assemblies  42   a ,  42   b  of the guard group  38  to change the door  50   a ,  50   b  posture from the open position to the closed position. In an exemplary embodiment the actuator cylinder  58  are hydraulic actuators, however it is envisioned that other actuators, such as electric motors, for example may be used however increase expense and complication. The actuator cylinder  58  extends and retracts to open a first door  50   a ,  50   b  which, in turn, urges rotation of the cam discs  110  which in turn moves the first and second actuator arms  114 ,  118  which urges the remaining doors  50   a ,  50   b  to open/close harmoniously with the door connected to the actuator. 
         [0025]    Referring to  FIG. 8  the actuator cylinder  58  will be described. The actuator cylinder  58  rod end is withdrawn inside which is attached to the first actuator arm  114  and second actuator arm  118  which allows the door  50  to be under closed position. During this condition the stopper  130  is seen on top of the disc. And the first actuator arm  114  and second actuator arm  118  can be seen in retracted position. 
         [0026]    Referring to  FIG. 9  the actuator arms  114  and  118  will be described. The first actuator arms  114  and the second actuator  118  extend&#39;s which in order allows the guard group to open the doors  50  from the closed position to open position. During this condition the stopper  130  is seen at the bottom of the disc which prevents the excess movement of the cam disc  110 . 
         [0027]    Referring to  FIG. 10  the access to the guard group  38  will be described. The bottom guard has four major bolts  102 , on the frame  34 , which can be removed to access the entire guard group  38  for major service. 
         [0028]    Referring to  FIG. 11  the opening of the entire guard group  38  is described. The guard group  38  is attached to the hinge  122  in the frame  34 . Removing the bolts  102  ( FIG. 10 ) will allow the guard group to suspend from the hinge  122  which is an integral part of the frame  34 . 
       INDUSTRIAL APPLICABILITY 
       [0029]    The guard group  38  is useful for protecting an underside of a machine  10  and more specifically mechanical components, such as the prime mover  30 , a transmission, a hydraulic pump, etc., of the machine  10  from striking stumps, rocks or the like when the machine  10  is moving. The guard group  38  is also useful for protecting the mechanical components from debris accumulation, tar, oil sands or the like. Machines  10  need maintenance or repairs and the guard group  38  is useful for allowing maintenance personnel easy access to the mechanical components protected by the guard group  38 . The guard group  38  is preferred over other guards because the guard group  38  is powered, thus the maintenance personnel are not required to remove a large, heavy guard group from the machine rather, the guard group  38  may be powered between the open position and the closed position. 
         [0030]    If the guard group  38  is in the open position and maintenance personnel wish to move it to the closed position, the maintenance personnel powers the actuator cylinder  58  to move the first actuator arm  114  and the second actuator arm  118  through the cam disc  110 , and thus changes the guard group  38 , into closed position. In the illustrated embodiment the actuator cylinder  58  is powered by a hydraulic pump that is separate from the machine  10 , while in other embodiments the actuator cylinder  58  may receive power from the hydraulic pump on the machine  10 . The actuator cylinder  58  is sufficiently strong to hold the guard group  38  in the closed position, but maintenance personnel may wish to couple the doors  50  to the frame  34  with door bolts  134  or the like to minimize the possibility of the doors  50  from moving when struck by stumps, rocks or the like. 
         [0031]    If the guard group  38  is in the closed position and maintenance personnel wish to move it to the open position, the maintenance personnel must first remove the door bolts  134  coupling the doors  50  to the frame  34 . The maintenance personnel then power the actuator cylinder  58  to move the actuator cylinder  58 , and thus the guard group  38 , into the open position. When the guard group  38  is in the open position mechanical components are accessible for maintenance or repairs. 
         [0032]    The guard group  38  may be removed from the machine  10 , if a large mechanical component, such as the oil pan, needs to be removed from the machine  10 . 
         [0033]    The guard group  38  can be accessed for minor service by removing the four door bolts  134  which are fastened to the threaded opening  82  welded to the cross members  74 . 
         [0034]    The guard group  38  can be accessed for major service by removing the bolts  102  which are attached to the frame  34 . Removing the four bolts  102  will allow the guard group  38  to suspend from the hinge  122  and to move between open and close positions upon actuation of actuator cylinder  58 , during which the door bolts  134  should not be removed. 
         [0035]    It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated. 
         [0036]    Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.