Patent Publication Number: US-2023160419-A1

Title: Compact actuated shear pin

Description:
TECHNICAL FIELD 
     This disclosure relates generally to industrial machines, and, more specifically, to an actuated shear pin for selectively inhibiting relative movement of portions of the industrial machine. 
     BACKGROUND 
     Industrial machines, such as earth moving machines, construction machines, mining machines, or the like, can include movable work implements. For instance, a wheel loader can include a bucket disposed at a distal end of a lift arm. The lift arm is movable relative to a frame of the wheel loader, e.g., to lift and lower the bucket, and the bucket can be pivoted, e.g., to receive or dump a payload during material loading and transferring operations. 
     For desired operational performance, regular servicing or maintenance of industrial machines is performed. For inspection or maintenance of the lift arm and/or components associated with the lift arm, e.g., actuators, fluid transfer lines, of the like, the lift arm is generally maintained in a raised position. For instance, an operator may hold a lever in a position that actuates the lift arm to, and retains the lift arm in, the raised position. However, the lift arm may be brought down if one or more actuators malfunction, or if a person unwittingly moves the lever during inspection/maintenance. Some conventional maintenance routines include using an additional machine, such as a crane or service truck to retain the lift arm in the raised position. However, some wheel loaders are used in underground applications, were the use of additional machines is not practical or desired. 
     U.S. Pat. No. 10,995,470 describes an improvement to manually retaining a lift arm in a raised position. Specifically, the &#39;470 patent relates to a service pin assembly for a machine that includes a service pin and a tray for retaining the service pin. The tray of the &#39;470 patent can be manually moved between a first position that facilitates storage of the service pin with the machine and a second position that facilitates an engagement of the service pin with a lift arm of the machine and a frame of the machine to restrict relative movement therebetween. 
     While the &#39;470 patent describes an improvement to conventional systems that required manual retention of a lever in an actuated position, the &#39;470 patent requires a mechanic, operator or other individual to physically access the service pin and tray, e.g., by climbing onto the machine or approaching the location of the pin via a boom lift or the like. Physically accessing the pin can expose the individual to moving parts of the machine, which can be hazardous. 
     Example implementations of the present disclosure are directed toward overcoming the deficiencies described above. For instance, aspects of the present disclosure are directed to improved shear pin designs and methods of using shear pins to facilitate relative locking of components on industrial machines. 
     SUMMARY 
     In an aspect of the present disclosure, an example electric rope shovel includes a machine comprising: a frame; a lift arm coupled to the frame and movable relative to the frame; and an actuated pin assembly actuatable between a stowed configuration and a locking configuration, the actuated pin assembly including a stationary member; a movable member coupled to and movable relative to the stationary member; and a pin body coupled to the movable member and movable with the movable member relative to the fixed member, the pin body including (i) an interior surface at least partially defining an axial bore that, with the actuated pin assembly in the stowed configuration, surrounds at least a portion of the fixed member and (ii) an exterior surface that, with the actuated pin assembly in the locking position, contacts at least one of the lift arm or the frame to inhibit movement of the lift arm relative to the frame. 
     In another aspect of this disclosure, an example actuated pin assembly includes: an actuator comprising a movable member and a fixed member, the movable member being movable relative to the fixed member between a retracted position and an extended position; and a pin body coupled to the movable member to move with the movable member relative to the fixed member, the pin body including an interior surface at least partially defining an axial bore that, with the actuator in the retracted position, at least partially surrounds the fixed member of the actuator. 
     In yet another aspect of this disclosure, an example actuated pin assembly includes: an actuator comprising a movable member and a fixed member, the movable member being movable relative to the fixed member between a retracted position and an extended position; a pin body coupled to the movable member to move with the movable member relative to the fixed member, the pin body including an interior surface at least partially defining an axial bore; and a resilient member coupled to the movable member and contacting the interior surface of the pin body. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a perspective view of a portion of an industrial machine including an actuated pin assembly, in accordance with an example of the present disclosure. 
         FIG.  2    includes a perspective view of an actuated pin assembly, for use with a machine, in each of a stowed configuration and a locking configuration, in accordance with aspects of the present disclosure. 
         FIG.  3    is a cross-sectional view of the actuated pin assembly of  FIG.  2   , taken along the section line  3 - 3  in  FIG.  2   , in accordance with aspects of this disclosure. 
         FIG.  4    is a cross-sectional view of the actuated pin assembly of  FIG.  2   , taken along the section line  4 - 4  in  FIG.  2   , in accordance with aspects of this disclosure. 
         FIG.  5    is an exploded perspective view of aspects of the actuated pin assembly of  FIG.  2   , in accordance with aspects of this disclosure. 
         FIG.  6    is a flow chart representative of a process for controlling an industrial machine including an actuated pin assembly, in accordance with aspects of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure generally relates to industrial machines, such as wheel loaders, with movable implements. The improvements and techniques described herein can result in improved safety for workers tasked with maintaining and/or servicing such machines. Moreover, although the present disclosure is described in connection with industrial machines, the systems and techniques described herein may be useful in other implementations in which it is desirable to impede relative motion of mechanical components. Wherever possible throughout this disclosure, the same reference numbers will be used through the drawings to refer to the same or like features. 
       FIG.  1    illustrates a lift arm assembly  100  for use with an industrial machine. The industrial machine may be configured to perform work associated with a particular industry, e.g., underground mining, open pit mining, construction, excavation, or the like. Without limitation, the industrial machine may be an excavator, an underground mining loader, a load haul dump loader, a wheel loader, a skid steer loader, or any other machine having a lift arm assembly. 
     More specifically, the lift arm assembly  100  includes a frame  102 , a first lift arm  104   a  and a second lift arm  104   b  (collectively, the lift arms  104 ) coupled to, and movable relative to, the frame  102 . For clarity, only a portion of the frame  102  is illustrated. However, in examples, the frame  102  may support traction devices (e.g., wheels, tracks, or the like), one or more power sources (e.g., a hydrostatic drive, an engine, or the like), a cabin for housing an operator, and/or other features. In still further examples, the frame  102  shown in  FIG.  1    may be a portion of a larger frame assembly that supports some or all of the features just described and/or other features. For instance, the frame  102  may include a number of plates, beams, weldments, or other components forming a rigid frame. 
     The lift arms  104  are coupled to the frame  102  and are configured to rotate relative to the frame  102 , as noted above. More specifically, first ends  106  of the lift arms  104  are disposed to couple to the frame  102 , e.g., at a pivot  108 . The lift arms  104  move about the pivot  108  relative to the frame  102 . The pivot  108  may be embodied as one or more pins, latches, and/or any other coupling that facilitates pivoting of the lift arms  104  relative to the frame  102 . Second or distal ends  110  of the lift arms  104  are configured for attachment of a work implement, e.g., a bucket (not shown). For instance, in the example of  FIG.  1   , the distal ends  110  of the lift arms  104  are illustrated as including holes  112 , which may be sized and positioned to accept a pin, latch, or other feature that secures the work implement, as is generally known in the art. Although two lift arms  104  are illustrated, more or fewer lift arms (e.g., a single lift arm) may be provided. Moreover, the shape, size, and other attributes of the lift arms  104  are for example only. 
     Although omitted from  FIG.  1    for clarity, the lift arm assembly  100  may also include additional components, including but not limited to one or more lift arm actuators. Such lift arm actuators may operatively couple the lift arms  104  to the frame  102 . As in conventional applications, the lift arm actuators may be extended or retracted to raise or lower the lift arms  104 , e.g., relative to the frame  102 . The lift arm assembly  100  may also include one or more implement actuators, e.g., to manipulate a bucket or other implement coupled to the lift arms  104 . In examples, the lift arm actuator(s) and/or the implement actuator(s) may be hydraulic, electrostatic, electromagnetic, compressed air, or any type of actuator. Also in examples, the lift arm actuator(s) and/or the implement actuator(s) may be controlled autonomously, remotely, by an operator, e.g., via an operator interface associated with the machine, or otherwise. 
     As also illustrated in  FIG.  1   , the lift arm assembly  100  includes a first actuated pin assembly  114   a  and a second actuated pin assembly  114   b  (collectively, the actuated pin assemblies  114 ). The first actuated pin assembly  114   a  is associated with the first lift arm  104   a  and the second actuated pin assembly  114   b  is associated with the second lift arm  104   b . As discussed further herein, the pin assemblies  114  are configured to selectively impede motion of the lift arms  104  relative to the frame  102 . More specifically, as illustrated in the example of  FIG.  1   , the second actuated pin assembly  114   b  is mounted, via a mount  116 , to an inboard surface  118  of the second lift arm  104   b . Although not visible in  FIG.  1   , the first actuated pin assembly  114   a  may be similarly mounted to an inboard surface (e.g., facing the inboard surface  118  of the second lift arm  104   b ) of the first lift arm  104   a  via a mount like the mount  116 . The mount  116  is depicted schematically, and may include any features or components that facilitate mounting of the second actuated pin assembly  114   b  to the second lift arm  104   b . Without limitation, the mount  116  may be bolted or welded to the second lift arm  104   b , and the second actuated pin assembly  114   b  may be coupled to the mount  116  using bolts, welding, or other conventional fasteners or fastening mechanisms. 
     The actuated pin assemblies  114  are secured to the lift arms  104 , respectively, at a position to selectively inhibit movement of the lift arms  104  relative to the frame  102 . More specifically, and as detailed further below with reference to  FIGS.  2 - 4   , the actuated pin assemblies  114  are configured to selectively actuate between a stowed configuration and a locking configuration. Specifically, in the stowed configuration, the actuated pin assemblies  114  are disposed so as to not impede movement of the respective lift arms  104 , relative to the frame  102 . In contrast, in the locking configuration, a portion of the actuated pin assemblies  114  is disposed to prevent some movement of the respective lift arms  104  relative to the frame  102 . 
     In the example of  FIG.  1   , the first actuated pin assembly  114   a  is configured in the locking configuration. In this configuration, a pin body  122  of the first actuated pin assembly  114   a  extends beyond an outboard surface  124  of the first lift arm  104   a . In this position, the pin body  122  is disposed to limit travel of the first lift arm  104   a  relative to the frame  102 . Specifically, the pin body  122  is disposed to contact a surface  126  of the frame  102  to prevent movement of the first lift arm  104   a  relative to the frame  102  in a direction indicated by an arrow  128 . In the example of  FIG.  1   , the surface  126  may include a saddle or other contoured feature that generally corresponds to an outer surface of the pin body  122 . In other examples, a hole or other feature may be disposed in the frame  102 , with the pin body  122  being disposed in the hole to prevent relative movement of the frame  102  and the lift arm  104   a , as detailed herein. Although obscured in the view of  FIG.  1   , the second actuated pin assembly  114   b  may be similarly configured in a locking configuration, e.g., in which a pin body associated therewith extends outboard of the lift arm to contact a surface  130  (or opening or other feature) of the frame  102 . In the illustrated example, the actuated pin assemblies  114 , in the locking configurations, retain the lift arms  104  in a raised position. 
     In the stowed position (not illustrated in  FIG.  1   , but demonstrated in  FIG.  3   , discussed below), the pin body  122  is positioned so as to not contact the surface  126  of the frame  102 . In the illustrated example, the pin body  122  may be retracted into an opening  132  formed through the first lift arm  104   a . Accordingly, the first actuated pin assembly  114   a  is disposed at least partially in the opening  132  and at least a portion of the first actuated pin assembly  114   a , e.g., at least a portion of the pin body  122 , extends from the opening  132  in the locking configuration. Although obscured by the mount  116 , the second lift arm  104   a  may have an opening similar to the opening  132 , with portions of the second actuated pin assembly  114   b  being disposed in and/or configured to extend from the opening. Details of this arrangement are described further below, including with reference to  FIGS.  3  and  4   . 
       FIG.  1    also shows an actuated pin control system  134  associated with the lift arm assembly  100 . The actuated pin control system  134  is shown schematically, and includes one or more sensors  136 , one or more actuators  138 , and one or more controllers  140 . Generally, the actuated pin control system  134  facilitates actuation of the actuated pin assemblies  114 , e.g., between the stowed and locked configurations, discussed above. Aspects of the actuated pin control system  134  may be integrated into the individual actuated pin assemblies  114  and/or may be remote from the actuated pin assemblies  114 . In some examples, the actuated pin control system  134  facilitates remote actuation of the actuated pin assemblies  114 , e.g., between the stowed and locking configurations. Remote actuation obviates the need for a worker or operator to physically place or adjust the pin body, thereby improving safety outcomes. 
     In more detail, the sensor(s)  136  may include one or more sensors associated with the lift arms  104 , the frame  102 , and/or the actuated pin assemblies  114 . For instance, and without limitation, the sensor(s)  136  can include position and/or state sensors that sense a position or presence of the lift arms  104  relative to the frame  102 . In examples, data from the sensor(s)  136  can indicate that the lift arms  104  are in a raised position or a lowered position, e.g., relative to the frame  102 . In other examples, the sensor(s)  136  can include position and/or state sensors that sense a position or state of the actuated pin assemblies  114 . Without limitation, data from the sensor(s)  136  can indicate whether the actuated pin assemblies  114  are in the locking configuration or in the stowed configuration. Additional examples of the sensor(s)  136  are discussed further herein. 
     The actuator(s)  138  are configured to selectively actuate components of the lift arm assembly  100 . For instance, the actuator(s)  138  can include lift arm actuators, e.g., coupled to the frame  102  and to the lift arms  104 , that cause the lift arms  104  to move relative to the frame  102 , e.g., between a raised position and a lowered position. The actuator(s)  138  can also include actuators associated with the actuated pin assemblies  114 , e.g., actuation of which configures the actuated pin assemblies  114  in the stowed or locking configurations. As noted above, and although not illustrated in  FIG.  1   , the lift arm assembly  100  can also include one or more implement actuators, e.g., to move a bucket or other implement relative to the lift arms  104 . 
     The controller(s)  140  are configured to control aspects of the lift arm assembly  100 . The controller(s)  140  may include a central processing unit, a suitable memory component, various input/output peripherals, and other components typically associated with machine controllers. The controller(s)  140  may include programs, algorithms, data maps, etc., associated with operation of the aspects of the machine. In examples, the controller(s)  140  may be configured to receive information from multiple sources, such as, for example, the sensor(s)  136 , the actuator(s)  138 , and/or a machine operator for instance, via a control device or user interface element. In some instances, the controller(s)  140  may include a dedicated electronic control module (ECM) or other type of onboard computer of the machine. In some embodiments, aspects of the controller(s)  140  may be integrated into the sensor(s)  136  and/or the actuator(s)  138 , e.g., such that the sensor(s)  136  and/or the actuator(s)  138  may be configured to perform operations discussed herein. In this case, the controller(s)  140 , or certain aspects thereof, may be eliminated. 
     In examples detailed further below, including below with reference to  FIG.  6   , the controller(s)  140  may include logic to receive a request to secure the lift arm assembly  100 , e.g., a request from an operator to ready the lift arm assembly  100  for maintenance or inspection. For instance, as noted above, it may be desirable to secure or “lock” the lift arms  104  in a raised position, e.g., relative to the frame  102 . The controller(s)  140  may also include functionality to receive sensor data from the sensor(s)  136 . For example, the controller(s)  140  can receive sensor data from the sensor(s)  136  indicative of a position or state of the lift arms  104  and/or the actuated pin assemblies  114 . Based on data from the sensor(s)  136 , the controller(s)  140  can determine that the lift arms  104  are in a raised position, and thus capable of being locked out. The controller(s)  140  can also include logic to generate and/or send one or more signals to control the actuator(s)  138 . For example, when the controller(s)  140  determine, from the sensor data, that the lift arms  104  are in the raised position, the controller(s)  140  may control actuators associated with the actuated pin assemblies  114  to configure the actuated pin assemblies  114  in the locking configuration. The controller(s)  140  may also include logic to determine that the actuated pin assemblies  114  are in the locked configuration, e.g., based on data from one or more of the sensor(s)  136  associated with the actuated pin assemblies  114 . Additional functionality associated with the controller(s)  140  is detailed further herein. 
     As will be appreciated from the foregoing, the controller(s)  140  may be configured to control the actuated pin assemblies  114 , e.g., remotely. As a result, the arrangement and techniques described herein can obviate the need for an operator, mechanic, or other individual to physically place a shear pin to lock out the lift arms  104 . Accordingly, aspects of this disclosure provide improved safety outcomes. 
     The lift arm assembly  100  illustrated in  FIG.  1    is for example only; modifications are contemplated. For example, although each of the lift arms  104  is illustrated in  FIG.  1    as including one of the actuated pin assemblies  114 , in other examples only a single instance of the actuated pin assemblies may be provided. For instance, when the first lift arm  104   a  and the second lift arm  104   b  are fixed to each other, a single instance of the actuated pin assemblies  114 , e.g., only the first actuated pin assembly  114   a , may be sufficient to retain both lift arms  104  in the raised position. 
     Moreover, individual of the lift arms  104  may include more than one instance of the actuated pin assemblies  114 . For example, multiple instances of the actuated pin assemblies  114  may be disposed along a length of the lift arms  104 , each configured to secure the lift arms  104  at a different position relative to the frame  102 . With specific reference to  FIG.  1   , although not illustrated, an additional instance of the actuated pin assemblies  114  may be disposed to cooperate with holes  142  relatively closer to the distal end  110  of the first lift arm  104   a . In this example, the additional instance of the actuated pin assemblies may include a pin body that contacts an additional surface  144  of the frame  102 . As will be appreciated, this example contact will retain the first lift arm  104   a  in a different position, relative to the frame  102 , than that illustrated. 
     Moreover, although the actuated pin assemblies  114  are illustrated as being secured to the lift arms  104 , in other examples, the actuated pin assemblies  114  may be coupled to the frame  102 . In such examples, the pin body  122 , in the locking configuration, may be contacted by a surface of the lift arms  104 . Stated differently, in the locking configuration, the pin body  122  may be disposed in a travel path of the lift arms  104 , e.g., a travel path relative to the frame  102 . Moreover, although the actuated pin assemblies  114  are disposed to selectively allow/prevent movement of the lift arms  104  relative to the frame  102 , other instances of the actuated pin assemblies  114  may be used to prevent other relative movement. Without limitation, the actuated pin assemblies  114  may be disposed to selectively prevent movement of an implement relative to the lift arms  104 , of articulating frame portions, and/or of any two components configured to move relative to each other. As will be appreciated with the benefit of this disclosure, the features and techniques described herein may be useful to prevent relative movement of any mechanical components in many applications. Aspects of this disclosure are not limited to use with lift arms on machines. 
       FIG.  2    is a perspective view showing an actuated pin assembly  200  in more detail. The actuated pin assembly  200  may be one of the actuated pin assemblies  114 , for example. More specifically,  FIG.  2    shows the actuated pin assembly  200  in a stowed configuration  202  and in a locking configuration  204 , generally corresponding to the stowed and locking configurations, respectively, discussed above in connection with  FIG.  1   . 
     As illustrated in  FIG.  2   , the actuated pin assembly  200  includes a pin body  206 , which may correspond to the pin body  122 . The pin body  206  is illustrated as having a generally cylindrical, exterior surface  210 , e.g., a sidewall, extending between a first end  212  and an opposite, second end  214  (obscured in  FIG.  2   ). Although the exterior surface  210  is cylindrical in  FIG.  2   , the exterior surface  210  may be differently shaped, e.g., depending on the application. For instance, the exterior surface  210  may have one or more flat, arcuate, or other surface contours. In some examples, a contour of the exterior surface  210  may be configured to cooperate with a surface or feature on a part to be “locked” in the locking configuration  202 . However, the cylindrical sidewall  210  may be preferred in some examples, for instance, because the pin body  206  will have the same configuration regardless of a rotational orientation of the pin body  206 . 
     In the example of  FIG.  2   , and better illustrated in  FIGS.  3  and  4   , the pin body  206  is coupled to a movable member, embodied as a piston rod  216 . The piston rod  216  is disposed to move relative to a fixed or stationary member, embodied as a cylinder  208 . More specifically, the piston rod  216  is movable relative to the cylinder  208  between a retracted position and an extended position. In the example of  FIG.  2   , a distal end of the piston rod  216  is threaded, and a nut  218  retains the pin body  206  on the piston rod  216 . An axial bore  220  is formed in the first end  212  of the pin body  206 , and the distal end of the piston rod  216  and the nut  218  are disposed in the first bore  220 . This arrangement is detailed further in  FIG.  3   , although the arrangement is also for illustration only. In one alternative example, the bore  220  may not be present, e.g., the nut  218  may be secured to the first end  212  of the pin body  206 . The threaded nut  218  is only one example of a retaining fastener that can be secured to the piston rod  216  to secure the pin body  206  to the piston rod  216 . Other retaining fasteners may include pins, clips, collars, and/or the like. 
     In the stowed configuration  202 , the piston rod  216  is retracted, relative to the cylinder  208 . Accordingly, the pin body  206  is also in a retracted position. As detailed further below with reference to  FIG.  3   , in the stowed configuration  202 , the pin body  206  is disposed to surround the cylinder  208 , e.g., by receiving a body of the cylinder  208  in an axial bore formed in the second end  214 . In the locking configuration  204 , when the piston rod  216  is extended, the pin body  206  is also extended from the cylinder  208 . In the stowed configuration  202 , as discussed above, the pin body  206  is disposed out of the path of travel of a first component (e.g., the frame  102 ) that moves relative to a second component (e.g., the lift arms  104 ) so as to not impede such relative motion. As also discussed above, in the locking configuration  204  the pin body  206  is disposed in the path of travel, e.g., to contact a surface of the first component. This contact limits (or prevents) relative movement of the components, thereby “locking” the components in a desired position. 
       FIGS.  3  and  4    show the interaction of the actuated pin assembly  200  with components of a machine. More specifically,  FIG.  3    is cross-sectional view  300  taken along section line  3 - 3  in  FIG.  2   , and  FIG.  4    is a cross-sectional view  400  taken along section line  4 - 4  in  FIG.  2   . In each of  FIGS.  3  and  4   , additional environment for the actuated pin assembly  200 , e.g., portions of the frame  102  and the lift arm  104 , is shown, also in cross-section. Moreover, in  FIGS.  3  and  4   , the elements introduced above with reference to, and labelled in,  FIG.  2   , are referred to, and labelled, using the same reference numerals. 
     The cross-sectional view  300  of  FIG.  3    corresponds to the stowed configuration  202 . As shown, the pin body  206  is disposed in the opening  132  extending through the lift arm  104 . Here, the lift arm  104  is illustrated as including three pieces, although more or fewer components could form the thickness of the lift arm  104  through which the opening  132  is formed. The pin body  206  is secured to the piston rod  216 , and the piston rod  216  is disposed to move relative to the cylinder  208 .  FIG.  3    also shows, schematically, that the cylinder  208  is coupled to the lift arm  104  via the mount  116 . 
     In more detail, the cylinder  208  and the piston rod  216  comprise portions of an actuator  302 , which may be one of the actuator(s)  138  discussed above. In more detail, the cylinder  208  at least partially defines a volume  304 . A piston  306 , to which the piston rod  216  is attached, is disposed in the volume  304 . A piston seal  308  seals the volume  304 . As in conventional actuators, the piston  306  is configured to slide, in an axial direction, relative to an inner surface of the cylinder  208  in response to a force applied on a side of the piston. In the illustrated example, the actuator  302  is a hydraulic actuator, and hydraulic fluid is selectively forced into the volume  304  to cause actuation of the piston  306 . Hydraulic fittings, supply lines, and/or the like are not shown, for clarity. Moreover, although  FIGS.  3  and  4    embody the actuator  302  as a hydraulic cylinder, other actuators are contemplated. Without limitation, the actuator  302  may be a compressed air actuator, an electromechanical actuator, a drive screw, or the like. 
     As also shown in  FIG.  3   , the pin body  206  includes an axial opening  310 . The axial opening  310  has a varied profile, e.g., formed by a number of different diameters, providing a contoured interior surface  312  of the pin body. For example, proximate the first end  212 , the axial opening  310  defines the bore  220  discussed above, which may be a first bore. The axial opening  310  also defines a protrusion  314 , an intermediate section  316 , and a second bore  318  proximate the second end  214 . As illustrated, the axial opening  310  also defines a first transitional section  320 , between the first bore  220  and the protrusion  314 , and a second transitional section  322 , between the intermediate section  316  and the second bore  318 . Thus, the interior surface  312  of the pin body includes, from the first end  212  of the pin body  206  to the second end  214 , the bore  220 , the first transitional section  320 , the protrusion  314 , the intermediate section  316 , the second transitional section  322 , and the second bore  318 . Functionality and attributes of the varied sections are described in more detail, below. Moreover, the sections, shapes, and sizes of the axial opening  310  are for example only. In examples, some or all of the sections may be combined, omitted, and/or differently sized/shaped. As detailed further herein, the axial opening  310  may be configured to provide clearance between the interior surface  312  and components of the actuator  302 , except at a cushioned interface. 
       FIG.  3    also shows additional aspects of the actuated pin assembly  200 . For example, a resilient member  324  (shown more clearly in the magnified insert of  FIG.  3   ) is disposed on the piston rod  216 , e.g., proximate a distal end of the piston rod  216 . The resilient member  324  cooperates with the protrusion  314  of the axial opening  310 . More specifically, the resilient member  324  includes a first radial protrusion  326  spaced from a second radial protrusion  328 . The first radial protrusion  326  and the second radial protrusion  328  form an annular channel  330  therebetween. As shown in  FIG.  3   , the resilient member  324  is disposed, in the axial direction, between washers  332 . Moreover, a sleeve  334  is disposed between the piston rod  216  and the resilient member  324 . In other examples, one or both of the washers  332  may be replaced by other members configured to retain the resilient member  324  in a fixed position on the piston rod  216 , e.g., in the axial dimension, or one or both of the washers  332  may be omitted entirely. As described further below, the washers  332  may also apply a force in the axial direction to the resilient member, e.g., to retain the resilient member at least partially compressed in the axial direction. 
     The resilient member  324  may be a compressible member, e.g., made of a polymer, rubber, or the like. In some implementations, the resilient member  324  may be embodied as an isolation mount, e.g., a mushroom mount. Isolation mounts are conventionally used to accommodate displacement, damp vibration, reduce shock, or the like. In this example, the resilient member may be formed as two pieces, e.g., a first piece including the first radial protrusion  326  and a second piece including the second radial protrusion  328 . Moreover, two or more of the first radial protrusion  326 , the second radial protrusion  328 , the washers  332  and/or the sleeve  334  may be formed as one or more integral parts. As will be appreciated, isolation mounts may have different sizes, shapes, durometer or hardness characteristics, or the like, e.g., depending on the application. In the example, the washers  332  and/or the sleeve  334  may be harder than the resilient member  324 . For instance, the washers  332  and/or the sleeve  334  may be metal or other relatively rigid materials. 
     In still further examples, the resilient member  324  may be embodied as one or more other components that provide for non-destructive displacement of the pin body  206  relative to the piston rod  216 , as described herein. As noted above, polymeric members may provide for such displacement, but other types of resilient members  324 , such as springs, spaced-apart magnets, e.g., spaced in the radial direction, or the like, also are contemplated. 
     The actuated pin assembly  200  also includes a disc  336  arranged closer to the distal end of the piston rod  216  than the resilient member  324 . Specifically, the disc  336  includes an axial opening sized to retain the outer surface of the piston rod  216 , and the disc  336  is positioned between the resilient member  324  and the nut  218 . In some examples, the disc  336  may be substantially cylindrical and the axial opening of the disc  336  may also be round. However, in other examples the disc  336  and/or the piston rod  216  may include anti-rotation features. In the example illustrated in  FIG.  3   , the piston rod  216  includes a number of flats  338  (shown more clearly in  FIG.  5   , discussed below) forming a non-circular profile for the piston rod  216  proximate the threaded end. The axial opening in the disc  336  has a contour to match the non-circular profile of the piston rod  216 , e.g., at straight or planar segments corresponding to the flats  338 . Accordingly, the flats  338  may require that the disc  336  be oriented on the piston rod  216  in one or more specific ways. Moreover, the flats  338  ensure that the disc  336  does not rotate relative to the piston rod  216 . For example when the nut  218  is tightened on the piston rod  216 , the disc  226  will not rotate relative to the piston rod  216 , e.g., if there is friction between the nut  218  and the disc  336 . Although the example of  FIG.  3    includes the flats  338  on the piston rod  216  and corresponding flats on the axial opening of the disc  336 , other arrangements and configurations may be used to reduce inhibit rotation of the disc  336  relative to the piston rod  216 . For instance, any non-circular profiles, a keyed arrangement, or the like, may be used. 
     During assembly, the resilient member  324 , washers  332 , and the disc  336  are placed over the distal end of piston rod  216 , e.g., with one of the washers  332  contacting a step  340  formed on the piston rod  216 . As will be appreciated, the step  340  may be formed from a reduction in the diameter of the piston rod  216 , although in other examples the step  340  may be formed via a collar or other diameter-altering structure secured to an outer surface of the piston rod  216 . The step  340  provides an axial positioning of the resilient member  324  and other features just discussed. Specifically, the step  340  provides a rigid surface that inhibits further axial displacement, relative to the piston rod  216 . Threading the nut  218  onto the piston rod will cause the disc  336  to move in the axial direction, thereby applying a force to compress the resilient member  324  in the axial direction, e.g., between the step  340  and the nut  218 . The compression caused by tightening the nut  218  will cause the first and second radial protrusions  326 ,  328  to “pinch” the protrusion  314  of the axial opening  310  of the pin body  206 . In the illustrated embodiment, the sleeve  334  may be sized, and sufficiently stiff, to maintain an axial distance between the washers  332  and prevent further tightening of the nut  218 . In some examples, the nut  218  may be tightened to a predetermine torque, e.g., based on properties of the resilient member  324 , a loading of the resilient member  324 , and/or the like. 
     As noted above, the flats  338  or similar feature(s) may be provided to prevent relative rotation of the disc  336  to the piston rod  216  during tightening of the nut  218 . However, as will be appreciated, the disc  336  and the piston rod  216  may rotate, e.g., together, during tightening of the nut  218 . Accordingly, aspects of this disclosure also include a tool interface, via which rotation of the disc  336 , e.g., relative to the pin body  206 , may be prevented. In the example of  FIG.  3   , a threaded hole  342  is formed through the disc  336 . The threaded hole  342  is offset from a central axis of the piston rod  216 . The threaded hole  342  is configured to selectively receive a threaded bolt  344 . With the threaded bolt  344  threaded into the threaded hole, a torque may be applied to the nut  218 , to tighten the nut  218  as discussed above, and a tool, such as a wrench, may be coupled to a head of the threaded bolt to apply a force that counters the torque applicated to the nut  218 . In this example, once the nut is sufficiently tightened, the threaded bolt  344  can be removed. 
     In this example, the threaded bolt  344  is sufficiently long to extend past the first end  212  of the pin body  206 , e.g., for ready engagement by the tool. However, in other examples the bolt head may be disposed in the first bore  220  and may be accessed by a socket or similar tool. Similarly, the nut  218  may be tightened using a socket wrench, e.g., because the nut  218  is disposed in the first bore  220 . Other tool interfaces and/or tool interface arrangements also are contemplated. For example, multiple instances of the threaded hole  342  may be formed through the disc  336 , e.g., circumferentially spaced from each other. In this example, a tool may be configured to contact each of a plurality of bolts disposed in the threaded openings. Without limitation, the tool may have a plurality of surfaces configured to engage with the bolts. In other examples, instead of the threaded opening, the disc  336  can be replaced with a protrusion, e.g., that is engageable with a tool (such as a socket wrench) or with a differently-shaped opening that can receive a different tool, e.g., an Allen key or the like. 
     In the illustrated example, the portions of the axial opening  310  provide for coupling of the piston rod  216 , e.g., via the protrusion  314  and the resilient member  324 . However, at other axial positions of the pin body  206 , the interior surface  312  is sized to be radially spaced from the piston rod  216  and other components associated with the piston rod  216 . For example, the disc  336  is spaced from the first bore  222 , the washers  332  are spaced from the first transitional section  320  and the intermediate section  316 . The piston rod  216  and the cylinder  208  also are spaced from the interior surface  312 . As detailed further below, minimizing contact of the pin body  206  and the piston rod  216  to the interface at the protrusion  314  and the resilient member  324  may prevent damage to both the actuator  302  and the pin body  206 , e.g., by controlling how, and where, contact is made. 
     In the example of  FIG.  3   , in the stowed configuration, at least a portion of the cylinder  208  is disposed in the second bore  318 . Stated differently, the pin body  206  acts as a sleeve that receives at least a portion of the cylinder therein in the stowed configuration. As noted above, the outer surface of the cylinder  208  is radially spaced from the interior surface  312  of the pin body  206 , e.g., at the second bore  318 . This arrangement reduces an overall length of the actuated pin assembly  200 . For example, this reduced length may facilitate incorporation of the actuated pin assembly  200  into existing machines and/or work implements, such as the lift arm assembly  100  with minimal modification or clearance requirements. 
     In the example of  FIG.  3   , the mount  116  couples the cylinder  208  to the side of the lift arm  104  such that the pin body  206  is substantially entirely disposed in the opening  132 . The opening  132  and the pin body  206  are sized to provide a clearance fit, e.g., such that the exterior surface  210  of the pin body  206  is spaced from the inside of the opening  132 . Also in the stowed configuration shown in  FIG.  3   , the pin body  206  does not extend from the opening  132 , e.g., in the axial direction, into a path of travel of the frame  102 . More specifically,  FIG.  3    also shows a portion of the frame  102 , and in the illustrated configuration, the lift arm  104  is free to move relative to the frame  102 , e.g., generally in the direction of an arrow  342 , which corresponds in direction to the arrow  128  of  FIG.  1   . 
       FIG.  4    shows the actuated pin assembly  200  in the locking configuration. In this example, the piston rod  216  is extended, e.g., relative to the cylinder  208 . More specifically, the piston  306  is moved relatively closer to the piston seal  308 . In this configuration, the pin body  206  extends into the path of travel of the frame  102  (e.g., relative to the lift arm  104 ). As will be appreciated, the exterior surface  210  of the pin body  206  contacts the surface  126  of the frame  102  to prevent continued motion of the lift arm  104 , e.g., in the direction of travel represented by the arrow  342 . As noted above, although the surface  126  is shown as an upper surface or saddle associated with the frame  102 , in other examples the pin body  206  may engage with an opening or hole formed in the frame  102 . Use of the opening or hole may require greater positioning precision before actuating the pin body  206  to the locking configuration, but may also have the benefit of restricting substantially all relative movement of the lift arm  104  relative to the frame  102 . Moreover, although the lift arm  104  is illustrated as including a hole through which the pin body  206  extends, in other examples the hole may be replaced with different openings and/or different surfaces. For example, and without limitation, the pin body  206  may be configured to contact a surface of the lift arm  104  that includes a saddle or other surface features, like the surface  126 . 
     In the example of  FIG.  4   , the actuated pin assembly  200  may be subjected to large shear loads. Specifically, with the pin body  206  extended into the travel path of the frame  102  the pin body  206  will experience a first shear force at a first region  402  and a second shear force at a second region  404 . The first shear force at the first region  402  results from contact of the pin body  206  with the lift arm  104  and is represented in  FIG.  4    by a first arrow  406 . The second shear force at the second region  404  results from contact of the pin body  206  with the frame  102  and is represented in  FIG.  4    by a second arrow  408 . Because the first shear force and the second shear force are in generally opposite directions and are spaced from each other, e.g., in a direction parallel to the axis of the actuated pin assembly  200 , components of the actuated pin assembly  200  may be subjected to a bending or twisting resulting from the first and second shear forces. However, in examples of this disclosure, the resilient member  324  is configured to offset, e.g., absorb, these forces. For instance, the resilient member  324  may allow for movement of the pin body  206  relative to the piston rod  216  and/or other components of the actuator  302 , while preventing the interior surface  312  of the pin body  206  from contacting components of the actuated pin assembly  200 . Stated differently, the resilient member  324  may allow for a pliable connection between the pin body  206  and the actuator  302  that absorbs the relative displacement until the pin body  206  fully contacts the surface  126 . This contact results in substantially all loads being transferred from the pin body  206  to the contact surface  126 , e.g., without being transferred to the piston rod  216 . Stated differently, the resilient member  324  decouples the cylinder from the pin load, by absorbing displacement caused by offsets resulting from clearance between the pin body  206  and the opening  132 , mechanical tolerances, and/or the like. In some alternative examples a rigid connection may be used instead of the resilient member  324 , although such a rigid connection may completely transfer loads to the piston rod  216  and/or other components of the actuated pin assembly  200 . Such transfer of loads may lead to premature failure of the piston seal  308 , undesirable wear of the piston  306 , bending of the piston rod  216 , or other problems that could prevent proper functioning of the actuated pin assembly  200 . 
     In addition to using the resilient member  324  at the connection of the pin body  206  and the actuator  302 , the inventors have found that the positioning of the resilient member  324 , e.g., in the axial direction, may also provide benefits. As shown in  FIG.  4   , a gap  410  is disposed between the frame  102  and the lift arm  104 . As will be appreciated, the gap  410  provides clearance between the frame  102  and the lift arm  104  to allow the two components to move relative to each other, as discussed herein. In the locking configuration shown in  FIG.  4   , the resilient member  324  is generally aligned with the gap  410 , e.g., along a line  412 . In this position, the resilient member  324  may be better positioned to absorb the forces at the first region  402  and the second region  404 . However, the actuated pin assembly  200  is not limited to the resilient member  324  being aligned with the gap  410 . Without limitation, in other examples, the resilient member  324  may be offset from the line  412  and still function to absorb the displacement at the first region  402  and/or the second region  404  and allow the pin body  206  to bear the loads without transferring the loads to the piston rod  216 . 
       FIG.  5    is an exploded perspective view of portions of the pin assembly  200 . Specifically,  FIG.  5    shows additional details of the piston rod  216 , the resilient member  324 , and the disc  336 . For clarity, some components shown in  FIGS.  3  and/or  4    are omitted from  FIG.  5   , including but not limited to the washers  332  and the sleeve  334 . 
     In detail,  FIG.  5    shows the flats  338  as including four planar surfaces arranged at 90-degree intervals around a segment of the piston rod  216 . The disc  336  includes an axial opening  502  having four corresponding planar sections  504 . Accordingly, and as discussed above, the flats  338  and the planar sections  504  act as an anti-rotation feature. Accordingly, when the nut (not shown in  FIG.  5   ) is threaded onto the piston rod  216 , the disc  336  will not rotate relative to the piston rod  216 . As noted above, modifications to the illustrated arrangement are contemplated. 
       FIG.  5    also shows that the resilient member  324  can be formed of two pieces, e.g., a first piece  506  including the first radial protrusion  326  and a second piece  508  including the second radial protrusion  328 . In this example, the second piece  308  also includes a protrusion  510  that contacts the first piece  506  to define the channel  330  discussed above. 
       FIG.  6    is a flow chart corresponding to an example process  600  of using an actuated pin assembly, like the actuated pin assemblies  114 ,  200  discussed above. For example, and without limitation, some or all of the process  600  can be implemented by the actuated pin control system  134 , including the sensor(s)  136 , the actuator(s)  138 , and/or the controller(s)  140 . However, the process  600  is not limited to being performed by the actuated pin control system  134  or components thereof. 
     At an operation  602 , the process  600  includes receiving a signal to secure one or more lift arms in a locked position. For example, an operator or maintenance worker may determine that a machine including the lift arms  104  should be repaired, inspected, or the like, and may enter a command, e.g., via a switch, button or other user input, indicating that the lift arms  104  should be “locked out.” The user interface may generate a signal corresponding to the command, and transmit the signal to the controller(s)  140  in some examples. 
     At an operation  604 , the process  600  includes confirming that the lift arm(s) are in a position for locking. As detailed herein, the lift arms  104  may be locked, e.g., secured relative to the frame  102  in a raised position. The operation  604  may include receiving a signal confirming that the lift arms  104  are at (or above) the raised position. For example, the operation  604  can include receiving a signal, e.g., from the sensor(s)  136  or the actuator(s)  138  confirming that the lift arms  104  are raised above a predetermined height, past a predetermined angle, or the like. The sensor(s)  136  can also include presence/absence sensors, which may confirm that the frame  102  would not obstruct actuation of the pin assembly to the locking configuration, as detailed herein. In still further examples, the operation  604  may include a visual inspection, e.g., by an operator or maintenance worker, that the lift arms  104  are raised above a predetermined height. In this example, the operator/worker may be required to provide an input, e.g., via a user interface, confirming that the lift arms  104  are sufficiently positioned. 
     At an operation  606 , the process  600  includes configuring the actuated pin assembly in the locking configuration. Specifically, the actuator  302  of the actuated pin assembly  200  may be actuated to position the piston/piston rod in the extended position shown in  FIG.  4   . In the extended position, the pin body  206  is disposed in the relative path of the travel between the frame  102  and the lift arms  104 . An example of the locking configuration is also illustrated at  204  in  FIG.  2   . As will be appreciated, with the actuated pin assembly  200  in the locking configuration, lowering of the lift arms  104  is inhibited by the extended pin body  206 , thereby “locking out” the lift arms  104 . With the lift arms  104  locked out, repair, maintenance, and/or other services can be performed on the lift arm assembly  100  and/or other parts of the machine, with the lift arms  104  safely locked out. In other examples, the lift arms  104  may be locked out using the actuated pin assembly  200  when the machine is to be unattended. 
     In some examples, the operation  606  can also include confirming that the actuated pin assembly is in the locking configuration. Without limitation, the actuator  302  may include a sensor, e.g., a position sensor, that confirms that the piston rod  216  is in the extended position. Moreover, one or more sensor(s), such as a presence sensor or state sensor and which may be the sensor(s)  136 , may be disposed on the lift arm  104  and/or the frame  102  to confirm that the pin body  206  is in an extended position, corresponding to the locking configuration  204 . 
     At an operation  608 , the process  600  includes receiving a signal to return the lift arm to an operational state. For example, the operation  608  can include receiving a user input, e.g., from an operator or maintenance worker, that the machine should return to normal operation. The machine may include a user interface to facilitate such user input, and the user interface may be configured to generate a signal indicative of the desire to return the machine to functional. 
     At an operation  610 , the process  600  includes configuring the actuated pin assembly in a stowed configuration. For example, the operation  610  can include actuating the actuator  302  to retract the piston rod  216 , as in the example of  FIG.  3   .  FIG.  2    also shows the actuated pin assembly  200  in the stowed configuration  202 . As detailed herein, in the stowed configuration, the pin body  206  is disposed in the opening  132  formed through the lift arm  104  or some other position that does not inhibit relative movement of the lift arm  104  and the frame  102 . 
     In some examples, the operation  610  can also include confirming that the actuated pin assembly  200  is in the stowed configuration. Without limitation, the actuator  302  may include a sensor, e.g., a position sensor, that confirms that the piston rod  216  is in the retracted position. Moreover, one or more sensor(s), such as a presence sensor or state sensor and which may be the sensor(s)  136 , may be disposed on the lift arm  104  and/or the frame  102  to confirm that the pin body  206  is in the retracted position, corresponding to the stowed configuration  202 . 
     INDUSTRIAL APPLICABILITY 
     The present disclosure provides improved safety mechanisms, e.g., actuated pin assemblies, for use with conventional machines, such as industrial machines including lift arm assemblies. The actuated pin assemblies according to this disclosure provide improved safety over conventional lockout pins, resulting in reduced damage to equipment and/or safer working conditions, thereby reducing downtime for machines. The improvements and techniques described herein may be particularly useful on machines that are operated in confined spaces and/or that require frequent maintenance. For example, wheel loaders and/or other machines used in mines may require regular inspection, e.g., daily, weekly, or the like, and it may be difficult and/or inefficient to provide external machinery and/or equipment, such as cranes, to lockout portion of the machine. The present disclosure obviates the need for extra equipment to allow for safely securing portion of machine during inspection or the like. Moreover, despite the improvements detailed herein, the pin assemblies described herein may be used in conventional machines, e.g., with minimal to no modification to existing lift arm assemblies. 
     According to some implementations, a lift arm assembly  100  includes a lift arm  104  disposed to move relative to a frame  102 . An actuated pin assembly  114 ,  200  is disposed on the lift arm  104  or the frame  102 . The actuated pin assembly  114 ,  200  is actuatable between a stowed configuration  202  and a locking configuration  204 . In the stowed configuration  202 , the actuator pin assembly  114 ,  200  is disposed out of a travel path of the lift arms  104  relative to the frame  102 , e.g., to allow for conventional operation of the lift arm assembly  100 . In the locking configuration  204 , a portion of the actuated pin assembly  114 ,  200 , e.g., a pin body  206 , is disposed in the travel path of the lift arms  104  relative to the frame  102 , e.g., to prevent relative motion between the lift arms  104  and the frame. Actuation of the actuated pin assembly  114 ,  120  between the stowed configuration  202  and the locking configuration  204  may be accomplished remotely, e.g., via the actuated pin control system  134 , thereby obviating the need for a worker to manually adjust or place the shear pin. 
     In examples described herein, the actuated pin assembly  114 ,  200  includes the pin body  206  coupled to an actuator  302 . In examples, the actuator  302  may be a hydraulic actuator, e.g., including a cylinder  208  and a piston rod  216  movable relative to the cylinder  208 , between a retracted position and an extended position. The pin body  206  is coupled to the piston rod  216  such that the actuated pin assembly  114 ,  200  is in the stowed configuration  202  with the piston rod  216  retracted and in the locking configuration  204  with the piston rod  216  extended. The coupling of the pin body  206  to the piston rod  216  can be made via the resilient member  324 . The resilient member  324  allows for some movement of the pin body  206  relative to the piston rod  216 , e.g., to absorb relative displacement of the pin body  206  to the frame  102  and/or the lift arm  104 . 
     While aspects of the present disclosure have been particularly shown and described with reference to the examples above, it will be understood by those skilled in the art that various additional implementations may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such implementations should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof