Patent Publication Number: US-2022226979-A1

Title: Power Tool

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 16/261,488, filed Jan. 29, 2019, which claims priority to U.S. Provisional Application No. 62/623,917, filed Jan. 30, 2018 and U.S. Provisional Application No. 62/729,872, filed Sep. 11, 2018. 
    
    
     FIELD 
     The present disclosure relates generally to power tools. More particularly, the present disclosure relates to a hydraulic tool having a linear sensor for sensing ram assembly movement along with other operational conditions. 
     BACKGROUND 
     Hydraulic crimpers and cutters are different types of hydraulic power tools for performing work (e.g., crimping or cutting) on a work piece by way of a work head, such as a crimping head or a cutting head. In such tools, a hydraulic tool comprising a hydraulic pump is utilized for pressurizing hydraulic fluid and transferring it to a cylinder in the tool. This cylinder causes an extendable piston or ram assembly to be displaced towards the work head. Where the power tool comprises a hydraulic crimper, the piston exerts a force on the crimping head of the power tool, which may typically include opposed crimp dies with certain crimping features. The force exerted by the piston may be used for closing the crimp dies to perform crimp or compression on a work piece at a desired crimp location. 
     Crimping can result in a crimp taking place at an undesired crimp location and also taking place with an improper amount of pressure being exerted during the crimp process. As such, there is a general need for a hydraulic crimp tool that enables a more efficient and more robust resultant crimp. 
     SUMMARY 
     According to an example embodiment, a hydraulic tool includes a tool head and a moveable piston coupled to the tool head. The hydraulic tool head includes a plurality of jaws, which are operable to open and close for performing work on a workpiece. The hydraulic tool also includes a motor operable to drive the moveable piston to close the plurality of jaws to a closed position at which the work on the workpiece is completed. The hydraulic tool further includes a position sensor configured to detect when the plurality of jaws are at the closed position and responsively generate a sensor signal indicating that the plurality of jaws are at the closed position. Additionally, the hydraulic tool includes a controller configured to receive the sensor signal from the position sensor. The controller is configured to operate the motor based on the sensor signal that the controller receives from the position sensor. 
     According to another example embodiment, a hydraulic tool includes a tool head having a plurality of crimping jaws, which are operable to open and close to crimp a workpiece. The hydraulic tool also includes a moveable piston coupled to the tool head, a motor operable to drive the moveable piston to open and close the plurality of crimping jaws, and a plurality of sensors configured to sense a plurality of conditions over a stroke of the moveable piston. The hydraulic tool also includes a controller in communication with the plurality of sensors and configured to: (i) receive sensor information from the plurality of sensors, (ii) determine, based on the sensor information, a crimp profile over the stroke of the moveable piston, and (iii) determine, based on the crimp profile, a characteristic of the crimp performed on the workpiece. 
     According to another example embodiment, a power tool includes a tool head having a first thread and a frame having a second thread. The tool head is rotationally coupled to the frame by a threaded engagement between the first thread and the second thread. The power tool also includes a moveable piston, a motor capable of driving the moveable piston to perform work on a work piece, and a distance sensor configured to sense a movement of the moveable piston. The distance sensor is operable to provide sensor information indicative of the movement of the piston. The power tool further includes a controller configured to receive the sensor information from the distance sensor. The power tool also includes a spring biasing the distance sensor in a direction from the frame toward the tool head such that the distance sensor maintains a fixed position in the tool head when the tool head moves axially during rotation of the tool head relative to the frame. The controller operates the motor to perform work on the work piece based in part on the sensor information that the controller receives from the distance sensor. 
     The features, functions, and advantages can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments in which further details can be seen with reference to the following description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The novel features believed characteristic of the illustrative embodiments are set forth in the appended claims. The illustrative embodiments, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to the following detailed description of one or more illustrative embodiments of the present disclosure when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  illustrates a perspective view of a hydraulic tool, according to an example embodiment; 
         FIG. 2  illustrates a block diagram of certain components of the hydraulic tool illustrated in  FIG. 1 , 
         FIG. 3  illustrates another perspective view of the hydraulic tool illustrated in  FIG. 1 ; 
         FIG. 4  illustrates another perspective view of the hydraulic tool illustrated in  FIG. 1 ; 
         FIG. 5  illustrates a flowchart of an example crimping method utilizing a hydraulic tool, according to an example embodiment; 
         FIG. 6  illustrates a flowchart of an example crimping method utilizing a hydraulic tool, according to an example embodiment; and 
         FIG. 7  illustrates an alternative hydraulic tool  130  comprising a punch-style crimping head; 
         FIG. 8  is a plan side view of a crimping tool head in a closed state according to an example embodiment; 
         FIG. 9  is a plan side view of a crimping tool head in an open state according to the example embodiment of  FIG. 8 ; 
         FIG. 10  is an exploded view of the crimping tool head according to the example embodiment of  FIG. 8 ; 
         FIG. 11A  illustrates a hydraulic circuit that may be used with a hydraulic tool; 
         FIG. 11B  illustrates a portion of the hydraulic circuit illustrated in  FIG. 11A ; 
         FIG. 11C  illustrates a portion of the hydraulic circuit illustrated in  FIG. 11A ; 
         FIG. 12  illustrates a portion of the hydraulic circuit illustrated in  FIG. 11A ; and 
         FIG. 13  illustrates an exemplary operator panel that may be used with a hydraulic tool. 
         FIG. 14  illustrates a simplified block diagram of a hydraulic tool according to an example embodiment. 
         FIG. 15  illustrates a flowchart of an example method utilizing a hydraulic tool, according to an example embodiment. 
         FIG. 16  illustrates a flowchart of an example method utilizing a hydraulic tool, according to an example embodiment. 
         FIG. 17  illustrates a flowchart of an example method utilizing a hydraulic tool, according to an example embodiment. 
         FIG. 18  illustrates a simplified block diagram of a hydraulic tool according to an example embodiment. 
         FIG. 19  illustrates a simplified block diagram of a hydraulic tool according to an example embodiment. 
         FIG. 20  illustrates a partial cross-sectional view of a hydraulic tool with a rotatable tool head according to an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description describes various features and functions of the disclosed systems and methods with reference to the accompanying figures. The illustrative system and method embodiments described herein are not meant to be limiting. It may be readily understood that certain aspects of the disclosed systems and methods can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein. 
     Further, unless context suggests otherwise, the features illustrated in each of the figures may be used in combination with one another. Thus, the figures should be generally viewed as component aspects of one or more overall implementations, with the understanding that not all illustrated features are necessary for each implementation. 
     Additionally, any enumeration of elements, blocks, or steps in this specification or the claims is for purposes of clarity. Thus, such enumeration should not be interpreted to require or imply that these elements, blocks, or steps adhere to a particular arrangement or are carried out in a particular order. 
     By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide. 
       FIG. 1  illustrates certain components of a hydraulic tool  100 , in accordance with an example implementation. Although the example implementation described herein references an example crimping tool, it should be understood that the features of this disclosure can be implemented in other similar tools, such as cutting tools. In addition, any suitable size, shape or type of elements or materials could be used. As just one example, the illustrated hydraulic tool  100  comprises a working head that utilizes a hex or six sided crimping head  114 . However, alternative styled crimping heads may also be used. As just one example, a punch-style or die less crimping head may also be used. For example,  FIG. 7  illustrates an alternative hydraulic tool  130  comprising a punch-style crimping head  132 . 
     Returning to  FIG. 1 , the hydraulic crimping tool  100  includes an electric motor  102  configured to drive a pump  104  by way of a gear reducer  106 . The pump  104  is configured to provide pressurized hydraulic fluid to a hydraulic circuit  124  comprising a hydraulic actuator cylinder  108 , which includes a piston slidably accommodated therein. The electric motor  102  is configured to drive a pump  104  by way of a gear reducer  106 . The pump  104  is configured to provide pressurized hydraulic fluid to a hydraulic actuator cylinder  108 , which includes a piston or ram that is slidably accommodated therein. 
     The hydraulic tool also comprises a controller  50 . For example,  FIG. 2  illustrates a block diagram of certain components of the hydraulic tools  100  and  130  illustrated in  FIGS. 1 and 7 . As illustrated in  FIG. 2 , the tool  100 ,  130  comprises the fluid reservoir  214  that is in fluid communication with the hydraulic circuit  124  and the pump  104 . The hydraulic circuit  124  and the pump  104  provide certain operating information and operational data to the controller  50  wherein the pump  104  is operated by way of the gear reducer  106 . 
     The controller  50  may include a processor, a memory  80 , and a communication interface. The memory  80  may include instructions that, when executed by the processor, cause the controller  50  to operate the tool  100 . In addition, the memory  80  may include a plurality of look up table of values. For example, at least one stored look up table may comprise work piece information or data, such as connector data. Such connector data may include, as just one example, connector type (e.g., Aluminum or Copper connectors) and may also include a preferred crimp distance for certain types of connectors and certain sizes of connectors. Such a preferred crimp distance may comprise a distance that the piston  200  and therefore the moveable crimping die  116  moves towards the crimp target area  160  (i.e., a work area) in order to achieve a desired crimp for a particular connector type having a specific size. 
     In one arrangement, the controller communication interface enables the controller  50  to communicate with various components of the tool  100  such as the user interface components  20 , the motor  102 , memory  80 , the battery  212 , and various components of the hydraulic circuit  124  (e.g., a pressure sensor  122 , and a linear distance sensor  150 ) (see, e.g.,  FIG. 3 ). 
     The battery  212  may be removably connected to a portion of the hydraulic tool, such as a bottom portion  134  of the hydraulic tool. By way of example, as illustrated in  FIG. 7 , the battery  212  may be removably connected to a bottom portion  134  of the hydraulic tool  130 , away from the crimping head  132 . However, the battery  212  could be removably mounted to any suitable position, portion, or location on the frame of the hydraulic tool  130 . 
     As illustrated in  FIG. 2 , the hydraulic tool  100  may further comprise user interface components  20  that provide input to the power tool, such as the controller  50  of the power tool. As will be described, such user interface components  20  may be used to operate the hydraulic tool  100 . For example, such user interface components  20  may comprise an operator panel, one or more switches, one or more push buttons, one or more interactive indicating lights, soft touch screens or panels, and other types of similar switches such as a trigger switch. As just one example, and as illustrated in  FIG. 7 , the user interface  136  may reside along a top surface of the hydraulic tool  130 . The hydraulic tool may also comprise a trigger switch  138  mounted along the bottom portion of hydraulic tool, near the battery  212 . 
       FIG. 13  illustrates an exemplary operator panel  1300  that may be used with a hydraulic tool, such as the hydraulic tool illustrated in  FIG. 7 . In this operator panel arrangement  1300 , the operator panel comprises a plurality of soft-touch operator buttons  1310  residing below a display  1320 , such as a liquid crystal display (LCD). In this illustrated arrangement, four buttons are provided: a first button  1312  comprising a scan button, a second button  1314  comprising an increase button  1314 , and a third button comprising a decrease button  1316 . 
     A fourth button  1318  comprising a select connector type button may also be provided. For example, prior to a crimp, a user can use the fourth button  1318  to either select a Cu connector, an Al connector or other connector type. The operator panel  1300  further comprises a first LED  1340  and a second LED  1350 . The first LED may be some other color than the second LED. For example, the first LED  1340  may comprise a green LED and the second LED may comprise a red LED. Alternative LED configurations may also be used. 
       FIG. 3  illustrates another perspective view of the hydraulic tool illustrated in  FIG. 1  and  FIG. 4  illustrates another perspective view of the hydraulic tool illustrated in  FIG. 1 . And now referring to  FIGS. 3 and 4 , positioned near the piston  200  is a linear distance sensor  150 . In this illustrated arrangement, the linear distance sensor  150  is mounted within a cylindrical bushing  126  that surrounds the piston rod  203 A of the piston  200 . This linear distance sensor  150  will operate to detect a linear displacement of the piston  200  during a crimping action. Specifically, based on the movement of the piston  200  during a crimping action, the linear distance sensor  150  will generate an output signal that is communicated to the controller  50 . This output signal is representative of a distance that the piston  200  has traveled from a particular reference point position of the ram or piston  200 . In one preferred arrangement, this particular reference point will be the position of the piston  200  when the piston  200  has been completely retracted to a most proximal position (e.g., a home position), as illustrated in  FIGS. 1 and 3 . 
     The linear distance sensor  150  also provides information as to the direction of motion of the piston  200 . That is, the linear distance sensor  150  can make a determination if the piston  200  is moving or extending towards a crimp target or if the piston  200  is moving away from or retracting away from the crimp target. This direction motion information may also be communicated to the controller  50 . The controller  50  may operate the tool based in part on this information, such as controlling the position of the piston during a crimp sequence. For example, the controller  50  may utilize this information to retract of the moveable ram to a predetermined position such that the controller controls the return position of the ram so subsequent crimps can be made without a full ram retraction, back to a home position. In addition, the controller  50  may utilize this information to drive or move the moveable ram to a predetermined position, for example, to hold a connector in place at a given position before a crimp sequence. 
     Exemplary linear distance sensors include, but are not limited to, linear variable differential transformer sensors, photoelectric distance sensors, optical distances sensors, and hall effect sensors. For example, such a hall effect sensor may comprise a transducer that varies its output voltage in response to a magnetic field created by an outer contour of an outer surface  213  of the moveable piston  200 . As just one example, grooves, slots and/or protrusions  215  may be machined, etched, engraved, or otherwise provided (e.g., by way of a label) along the outer surface  213  of the piston  200 . 
     In this illustrated hydraulic tool example, a frame and a bore of the tool  100  form the hydraulic actuator cylinder  108 . The cylinder  108  has a first end  109 A and a second end  109 B. The piston is coupled to a link mechanism  110  that is configured to move the moveable crimp head  116  of a crimp head  114 . The first end  109 A of the cylinder  108  is proximate to the crimp head  116 , whereas the second end  109 B is opposite the first end  109 A. 
     When the piston is retracted, the moveable head  116  may be pulled back to a fully retracted or a home position as shown in  FIGS. 1 and 3 . Alternatively, the moveable head  116  may be pulled back to a partially retracted position. 
     When pressurized fluid is provided to the cylinder  108  by way of the pump  104 , the fluid pushes the piston  200  inside the cylinder  108 , and therefore the piston  200  extends towards the crimp target placed within the work area  160 . As the piston  200  extends through the cylindrical bushing  126 , the linear sensor  150  senses the movement of piston  200  and provides this information to the controller  50 . 
     In one preferred arrangement, the linear sensor  150  continuously senses the movement of the piston  200 . As just one example, the linear sensor  150  may continuously sense the movement of the piston  200  during one or more of the entire crimp process as the ram assembly moves towards the crimping head, performs the crimp, and then retracts. However, as those of ordinary skill in the art will recognize, alternative sensing arrangements may also be utilized. As just one example, in certain arrangements, the controller may utilize the linear sensor  150  to sense the movement of the piston  200  only during a specified period of time (e.g., only during when the piston rod  200  is driven towards the work piece or only during a crimping action). In yet an alternative arrangement, the linear sensor  150  may be utilized to only periodically sense the movement to the piston  200 . 
     As the piston  200  extends, the link mechanism  110  causes the moveable crimp head  116  to move towards the stationary head  115 , and may therefore cause the working heads  115 ,  116  to act upon or crimp a connector that has been placed in the crimp work area  160 . When the crimping operation is performed, the controller  50  can provide instructions to the hydraulic circuit  124  to stop the motor  102  and thereby release the high pressure fluid back to a fluid reservoir  214  as described in greater detail herein. 
     As mentioned, to increase the efficiency of the hydraulic tool  100 , it may be desirable to have a tool where the piston  200  could move at non-constant speeds and apply different loads based on a state of the tool, the crimping operation, and/or the type of crimp that is desired. For instance, the piston  200  may be configured to advance rapidly at a fast speed while travelling within the cylinder  108  before the moveable crimping head  116  reaches a connector to be crimped. Once the moveable crimping head  116  reaches the connector, the piston  200  may slow down, but cause the moveable crimp head  116  to apply a large force to perform the crimp operation. Described next is an exemplary hydraulic circuit  124  that is configured to control the crimping operation of the hydraulic tool  100 . 
     Returning to  FIGS. 3 and 4 , the tool  100  includes a partially hollow piston  200  moveably accommodated within the cylinder  108 , which is formed by a frame  201  and a bore  202  of the tool  100 . The piston  200  includes a piston head  203 A and a piston rod  203 B extending from the piston head  203 A along a central axis direction of the cylinder  108 . As shown, the piston  200  is partially hollow. Particularly, the piston head  203 A is hollow and the piston rod  203 B is partially hollow, and thus a cylindrical cavity  230  is formed within the piston  200 . 
     The motor  102  drives the pump  104  to provide pressurized fluid through a check valve  204  to an extension cylinder  206 . The extension cylinder  206  is disposed in the cylindrical cavity formed within the partially hollow piston  200 . The piston  200  is configured to slide axially about an external surface of the extension cylinder  206 . However, the extension cylinder  206  is affixed to the cylinder  108  at the second end  109 B, and thus the extension cylinder  206  does not move with the piston  200 . 
     The piston  200 , and particularly the piston rod  203 B, is further coupled to a ram  208 . The ram  208  is configured to be coupled to and drive the moveable crimp head  116 . 
     The piston head  203 A divides an inside of the cylinder  108  into two chambers: a first chamber  210 A and a second chamber  210 B. The chamber first  210 A is formed between a surface of the piston head  203 A that faces toward the ram  208 , a surface of the piston rod  203 B, and a wall of the cylinder  108  at the first end  109 A. The second chamber  210 B is formed between the a surface of the piston head  203 A that faces toward the motor  102  and the pump  104 , the external surface of extension cylinder  206 , and a wall of the cylinder  108  at the second end  109 B. Respective volumes of the first chamber  210 A and the second chamber  210 B vary as the piston  200  moves linearly within the cylinder  108 . The second chamber  210 B includes a portion of the extension cylinder  206 . 
     The pump  104  is configured to draw fluid from the fluid reservoir  214  to pressurize the fluid and deliver the fluid to the extension cylinder  206  after a user initiates a crimp command. Such a crimp command may come by way of the user entering such a command by way of the user interface components  20  (see,  FIG. 2 ). For example, a crimp command could be initiated by the user entering a crimp command by way of the user interface  136  or the toggle switch  136  as illustrated in  FIG. 7 . 
     The reservoir  214  may include fluid at a pressure close to atmospheric pressure, e.g., a pressure of 15-20 pounds per square inch (psi). Initially, the pump  104  provides low pressure fluid to the extension cylinder  206 . The fluid has a path through the check valve  204  to the extension cylinder  206 . The fluid is blocked at high pressure check valve  212  and a release valve  216 , which is coupled to, and actuatable by the controller  50 . 
     The fluid delivered to the extension cylinder  206  applies pressure on a first area A 1  within the piston  200 . As illustrated, the first area A 1  is a cross section area of the extension cylinder  206 . The fluid causes the piston  200  and the ram  208  coupled thereto to advance rapidly. Particularly, if the flow rate of the fluid into the extension cylinder  206  is Q, then the piston  200  and the ram  208  move at a speed equal to V 1 , where V 1  could be calculated using the following equation: 
     
       
         
           
             
               
                 
                   
                     V 
                     1 
                   
                   = 
                   
                     Q 
                     
                       A 
                       1 
                     
                   
                 
               
               
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
     
     Further, if the pressure of the fluid is P 1 , then the force F 1  applied on the piston  200  could be calculated using the following equation: 
         F   1   =P   1   A   1 |  (2)
 
     Further, as the piston  200  extends within the cylinder  108 , hydraulic fluid is pulled or drawn from the reservoir  214  through a bypass check valve  218  into the chamber  210 B. As the piston  200  begins to extend, pressure in the second chamber  210 B is reduced below the pressure of the fluid in the fluid reservoir  214 , and therefore the fluid in the fluid reservoir  214  flows through the bypass check valve  218  into the chamber  210 B and fills the second chamber  210 B. Preferably, the controller  50  is monitoring both the pressure hydraulic fluid by way of the pressure sensor  122  and is also monitoring the movement of the piston  200  based on input that it receives from the linear distance sensor  150 . 
     As the piston  200  and the ram  208  extend, the moveable crimping die  116  and stationary crimping die  115  move toward each other in preparation for crimping a connector placed within the crimping area  160 . As the moveable die  116  reaches the connector, the connector resists this motion. Increased resistance from the connector causes pressure of the hydraulic fluid provided by the pump  104  to rise. 
     The tool  100  includes a sequence valve  120  that includes a poppet  220  and a ball  222  coupled to one end of the poppet  220 . A spring  224  pushes against the poppet  220  to cause the ball  222  to prevent flow through the sequence valve  120  until the fluid reaches a predetermined pressure set point that exerts a force on the ball exceeding the force applied by the spring  224  on the poppet  220 . For example, the predetermined pressure set point that causes the sequence valve  120  to open could be between 350 and 600 psi; however, other pressure values are possible. This construction of the sequence valve  120  is an example construction for illustration, and other sequence valve designs could be implemented. 
     Once the pressure of the fluid exceeds the predetermined pressure set point, fluid pressure overcomes the spring  224  and the sequence valve  120  opens, thus allowing the fluid to enter the second chamber  210 B. As such, the fluid now acts on an annular area A 2  of the piston  200  in addition to the area A 1 . Thus, the fluid acts on a full cross section of the piston  200  (A 1 +A 2 ). For the same flow rate Q, used in equation (1), the piston  200  and the ram  208  now move at a speed equal to V 2 , where V 2  could be calculated using the following equation: 
     
       
         
           
             
               
                 
                   
                     V 
                     2 
                   
                   = 
                   
                     Q 
                     
                       
                         A 
                         1 
                       
                       + 
                       
                         A 
                         2 
                       
                     
                   
                 
               
               
                 
                   ( 
                   3 
                   ) 
                 
               
             
           
         
       
     
     As indicated by equation (3), V 2  is less than V 1  because of the increase in the area from A 1  to (A 1 +A 2 ). As such, the piston  200  and the ram  208  slow down to a controlled speed that achieves a controlled, more precise working operation. However, the pressure of the fluid has increased to a higher value, e.g., P 2 , and thus the force applied on the piston  200  also increases and could be calculated using the following equation: 
         F   2   =P   2 ( A   1   +A   2 )|  (4)
 
     F 2  is greater than F 1  because of the area increase from A 1  to (A 1 +A 2 ) and the pressure increase from P 1  to P 2 . Thus, when the sequence valve  120  opens, high pressure hydraulic fluid can enter both the extension cylinder  206  and the chamber  210 B to cause the ram  208  to apply a large force that is sufficient to crimp a connector at a controlled speed. 
     Higher pressure fluid is now filling the chamber  210 B due the opening of the sequence valve  120 . The high pressure fluid pushes a ball of the bypass checkvalve  218  causing the bypass check valve  218  to close, thus preventing fluid from the chamber  210 B to flow back to the fluid reservoir  214 . In other words, the bypass check valve  218  has fluid at reservoir pressure on one side and high pressure fluid in the chamber  210 B on the other side. The high pressure fluid shuts off the bypass check valve  218 , which thus does not allow fluid to be drawn from the reservoir  214  into the chamber  210 B. 
     The tool  100  includes a pressure sensor  122  configured to provide sensor information indicative of pressure of the fluid. The pressure sensor  122  may be configured to provide the sensor information to the controller  50 . 
     As will be described in greater detail with reference to the flowcharts of  FIGS. 5 and 6 , once the piston  200  begins to experience an increased pressure as it exerts an initial crimp force on an outer surface of the connector, the controller  50  will be directed to a lookup table for certain desired values. In one arrangement, based on user input information, the controller  50  will extract the desired crimp distance and a desired crimp pressure. The controller  50  then operates the motor  102  and the hydraulic circuit  124  so as to drive the piston  200  to this targeted crimp distance and to this targeted crimp pressure. When the linear distance sensor  150  senses that the piston  200  has moved to this targeted crimp distance, the controller  50  can then determine that the initiated crimp of the identified connector is complete. 
     Once the connector is crimped and the piston  200  reaches an end of its stroke within the cylinder  108 , hydraulic pressure of the fluid increases because the motor  102  may continue to drive the pump  104 . The hydraulic pressure may keep increasing until it reaches a threshold pressure value. In an example, the threshold pressure value could be 8500 psi; however, other values are possible. Once the controller  50  receives information from the pressure sensor  122  that the pressure reaches the threshold pressure value, the controller  50  may shut off the motor  102  so as to retract the piston and the ram  208  back to a desired position, such as a home or fully retracted position. 
     In one example, the tool  100  includes a return spring  228  disposed in the first chamber  210 A. The spring  228  is affixed at the end  109 A of the cylinder  108  and acts on the surface of the piston head  203 A that faces toward the piston rod  203 B and the ram  208 . When piston retraction has been actuated, the spring  228  pushes the piston head  203 A back. Also, pressure of fluid in the extension cylinder  206  and the second chamber  210 B is higher than pressure in the reservoir  214 . As a result, hydraulic fluid is discharged from the extension cylinder  206  through the release valve  216  back to the reservoir  214 . At the same time, hydraulic fluid is discharged from the second chamber  210 B through the high pressure check valve  212  and the release valve  216  back to the reservoir  214 , while being blocked by the check valve  218  and the check valve  204 . Particularly, the check valve  204  prevents back flow into the pump  104 . 
     Within some examples, the exterior surface of the frame  201  can provide a gripping portion  201 A to facilitate handling of the hydraulic tool  100 . In one implementation, the gripping portion  201 A of the hydraulic tool  100  can have a diameter of less than approximately 70 millimeters (mm). In another implementation, the gripping portion  201 A of the hydraulic tool  100  can have a diameter of approximately 65 mm. These implementations can provide for a relatively small, ergodynamic feature, which can be gripped by an operator to handle and/or stabilize the hydraulic tool  100  while applying a relatively high force to a workpiece or connector (e.g., approximately seven tons of output force or greater, approximately 15 tons of output force or greater, etc.). 
     In some examples, the gripping portion  201 A of the frame  201  can include a plurality of handle halves (not shown) made of, for instance, a plastic and/or a rubber material. The handle halves can enhance the tactile experience by providing a particular geometry, texture, and/or hardness that facilitates gripping the hydraulic tool  100 . However, in other examples, the gripping portion  201 A of the frame  201  can omit the handle halves as shown in  FIGS. 1-2 . This can help to reduce (or minimize) the diameter of the hydraulic tool  100  at the gripping portion  201 A. 
     To further reduce (or minimize) the diameter of the hydraulic tool  100  at the gripping portion  201 A, the gripping portion  201 A can be made from a relatively high strength material (e.g., relative to aluminum) such as, for example, steel. By using a relatively high strength material the wall of the gripping portion  201 A can be made relatively thin, thereby reducing the diameter of the gripping portion  201 A. For example, a wall of the gripping portion  201 A comprising steel can be approximately 4 mm to approximately 6 mm in thickness. Alternatively, a wall of the gripping portion  201 A comprising aluminum can be approximately 6 mm to approximately 7 mm in thickness. 
       FIG. 5  shows a flowchart of an example method  300  for crimping a connector by using a die less hydraulic crimper, according to an example embodiment. Method  300  shown in  FIG. 5  presents an embodiment of a method that could be used using the hydraulic tool as shown in  FIGS. 1-4, and 7 , for example. Further, devices or systems may be used or configured to perform logical functions presented in  FIG. 5 . In some instances, components of the devices and/or systems may be configured to perform the functions such that the components are actually configured and structured (with hardware and/or software) to enable such performance. In other examples, components of the devices and/or systems may be arranged to be adapted to, capable of, or suited for performing the functions, such as when operated in a specific manner. Method  300  may include one or more operations, functions, or actions as illustrated by one or more of blocks  310 - 410 . Also, the various blocks may be combined into fewer blocks, divided into additional blocks, and/or removed based upon the desired implementation. 
     It should be understood that for this and other processes and methods disclosed herein, flowcharts show functionality and operation of one possible implementation of present embodiments. Alternative implementations are included within the scope of the example embodiments of the present disclosure in which functions may be executed out of order from that shown or discussed, including substantially concurrent or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art. 
     At block  310 , the method  300  includes the step of a user entering certain information related to a desired crimp into the hydraulic tool. Such information may be entered into the tool via user interface components  20  as previously described. For example, at block  310 , a user may enter a type of connector that will be crimped. That is, the user may enter that an Aluminum connector is being crimped or that a Copper connector is being crimped. In addition, once the type of connector is selected and input into the tool, the user may be called upon to enter the size of the connector size into the hydraulic tool. Based on this entered data, the controller  50  of the hydraulic tool  100 ,  130  will be able to determine a targeted crimp pressure to ensure a proper crimp. In addition, based on this entered data, the controller  50  of the hydraulic tool  100 ,  130  will also be able to determine a targeted crimp distance that the piston  200  will move in order to perform the desired crimp. 
     For example, once this data has been entered into the tool, at block  320 , the method  300  includes the step of the controller  50  looking up the crimp target distance and the crimp pressure that is to be used for the specific information input at block  310 . The method  300  utilizes, at least in part, the information that a user inputs at block  310  to look up these crimp target distance and crimp pressures. Such crimp information may be contained in a look up table that is stored in the memory  80  that is accessible by way of a controller  50 . (See, e.g.,  FIG. 2 ). 
     At block  330 , the method  300  queries by way of the controller  50  whether a tool trigger has been pulled in order to commence or initiate a crimp. For example, such a tool trigger may comprise the trigger switch  138  as illustrated in  FIG. 7 . If at block  330 , the controller  50  determines that the tool trigger has not been pulled, then the method  300  returns back to the start of block  330  and waits a certain period of time to query again whether the tool trigger has been pulled. 
     If at block  330 , the controller  50  determines that the tool trigger has been pulled, a crimping action commences. That is, the method  300  will proceed to block  340  where the controller  50  initiates activation of the hydraulic tool motor  102 . After the motor  102  has been activated, as herein described, internal pressure within the hydraulic tool will begin to increase. Once the ram or piston  200  begins to move in a distal direction or in a crimping direction, the controller  50  will detect and monitor the movement of the piston  200  as it moves in this direction. Specifically, piston  200  movement will be detected and monitored by way of the linear distance sensor  150  in order to determine if the piston  200  moves the targeted crimp distance, as previously determined by the controller  50  at block  320 . After the piston  200  begins its movement towards the crimping target as herein described, at block  350 , the controller  50  monitors whether the piston  200  achieves its target crimp distance. In one preferred arrangement, the target crimping distance may be determined by the controller  50  by analyzing position information that it receives from the linear distance sensor  150  as described herein. If at block  350  the controller  50  determines that the piston  200  has not yet reached the target crimp distance, the method  300  proceeds to block  360 . At block  360  of the method  300 , the controller  50  determines if the hydraulic circuit  124  of the hydraulic tool  100  resides at maximum hydraulic pressure, preferably by way of a pressure transducer (e.g., pressure transducer  122 ). If at block  360  the method  300  determines that the maximum hydraulic pressure has not been reached, then the method  300  returns to block  340  and the controller  50  continues to operate the motor  102  so to increase fluid pressure within the hydraulic circuit  124  so as to continue to drive the piston  200  towards the crimp work area  160 . 
     Alternatively, if at block  360 , the controller  50  determines that a tool maximum pressure has been reached, then the method  300  proceeds to block  370  where the motor  102  is stopped. 
     After the motor has been stopped at block  370 , the method  300  proceeds to block  380  where certain operating parameters may be recorded by the controller  50 . For example, at block  370 , the controller  50  may record the final crimp pressure as well as the crimp distance that the piston  200  traveled in order to complete the desired crimp. Thereafter, the method  300  proceeds to block  390  where the controller  50  may make a determination if the resulting crimp met the desired looked up crimp pressure and the desired crimp distance. For example, in one arrangement, the controller  50  would compare the recorded finished pressure and distance recorded at block  380  with the target crimp distance and target crimp pressure that the controller  50  pulled from the look up table at block  320 . If these pressure and/or distance values do not compare favorably, the method  300  proceeds to block  400  where the resulting failed crimp failure is indicated and then perhaps logged. Alternatively, if these values do favorably compare, then the method  300  proceeds to block  410  wherein a successful crimp may be indicated to the user, as described herein. In one arrangement, the controller  50  may also store this successful crimp in memory  80  and may also be logged in a tracking log, also stored in memory  80 . 
     In addition, the successful crimp may be visually and/or audibly noted to a user of the power tool  100  by way of some type of human interface device: e.g., illumination of a green light emitting diode of some other similar indication by way of one of the user interface components  20 . Alternatively, or additionally, an operator interface may be provided along a surface of the tool housing that provides such a visual and/or graphical confirmation that the previous crimp comprises a successful crimp. This could be the same or different operator interface that the user utilized at block  310  where the user enters crimp size and connector type information prior to crimp initiation. 
       FIG. 6  shows a flowchart of an alternative method  500  for crimping by using a die less hydraulic crimper, according to an example embodiment that does not require initial user input prior to initiating a crimp. Method  500  shown in  FIG. 6  presents an embodiment of a method that could be used using the hydraulic tools  100 ,  130  as shown in  FIGS. 1-4 and 7 , for example. Method  500  may include one or more operations, functions, or actions as illustrated by one or more of blocks  510 - 630 . Also, the various blocks may be combined into fewer blocks, divided into additional blocks, and/or removed based upon the desired implementation. 
     At block  510 , the method  500  includes an optional step of a user entering certain information prior to initiation of a desired crimp. For example, at block  510 , a user may enter a type of connector that will be crimped. For example, the user may enter that either an Aluminum connector is being crimped or that a Copper connector is being crimped. 
     At block  520 , the controller  50  of the hydraulic tool queries whether the tool trigger has been pulled in order to initiate a crimping operation. If at block  520 , the hydraulic tool controller  50  determines that no tool trigger has yet been pulled, the method  500  cycles back to block  510  and waits a certain period of time before this query is made again. 
     If at block  520  the controller  50  determines that the tool trigger has been pulled, a crimping action is initiated. That is, the method  500  proceeds to block  530  where the controller  50  starts the motor  102  such that hydraulic tool pressure will increase within the hydraulic circuit  124 , as described herein. After hydraulic pressure increases within the hydraulic circuit  124 , the piston  200  begins to move in the distal direction, towards the crimping head  114 . After movement of the piston  200 , the hydraulic tool  100  will detect and monitor the internal pressure of the tool  100 , as determined at block  540 . For example, pressure may be monitored by the controller  50  as it receives feedback information from the pressure sensor  122 . Specifically, the controller  50  will monitor the pressure to determine if a threshold pressure is detected. This threshold pressure will determine whether the piston  200  has first engaged an outer surface of a connector to be crimped. After the piston  200  begins its distal movement towards the crimping target, at block  540 , the controller  50  determines whether and when the tool achieves the threshold pressure also referred to as connector measure pressure. 
     If the controller  50  determines that the connector measure pressure has been met, and that therefore the piston  200  is starting to exert a force upon the outer diameter of the connector being crimped, the method proceeds to block  550 . At block  550 , a connector outer diameter is measured. In one preferred arrangement, this connector outer diameter may be measured by utilizing the linear distance sensor  150 . For example, the linear distance sensor  150  may provide distance information as to how far the piston  200  has traveled from a reference position (i.e., the piston home or retracted position). And since the controller  50  can determine the relative position of the piston  200  at that point in time, the controller  50  will therefore be able to determine the connector outer diameter. The controller  50  can therefor record this outer diameter in memory  80 . 
     After the connector outer diameter has been determined at block  550 , the controller  50  looks up a target crimp distance and a target crimp pressure via a lookup table, preferably stored in memory  80 . Pressure within the hydraulic circuit  124  continues to increase so that the piston  200  continues to move towards the crimping head  114  so as to complete the crimp. Next, at block  570  of method  500 , the controller  50  queries whether the targeted crimp distance has been achieved by the piston  200 . As previously described herein, in one arrangement, the controller  50  would receive this distance information regarding the targeted crimp distance from the linear distance sensor  150 . 
     If the controller  50  determines from the distance information provided by the linear distance sensor  150  that the targeted crimp distance has not yet been achieved, the method proceeds to block  580 . At block  580 , the controller  50  determines if the hydraulic tool resides  100  at a maximum hydraulic tool pressure. Preferably, the controller  50  receives pressure information from the pressure sensor  122  for this determination. If at block  580 , the controller  50  determines that the maximum hydraulic tool pressure has been reached, then the method  500  proceeds to block  590  where the controller  50  initiates a stoppage of the tool motor  102 . 
     Alternatively, if at block  570 , the controller  50  determines that a target crimp distance has been achieved (i.e., that the piston has indeed traveled the desired crimp target distance), then the method  500  proceeds to block  590  where the controller  50  issues an action to stop the motor  102 . As a result, the hydraulic circuit  124  will act as described herein so as to return the hydraulic fluid back to the fluid reservoir  214 . 
     After the motor  120  has been stopped at block  590 , the method  500  proceeds to block  600  where certain operating parameters may be recorded and/or information logged. For example, at block  600 , the controller  50  may record the final crimp pressure within the hydraulic circuit  124  as well as the final crimp distance that the piston  120  traveled so as to complete the crimp. Thereafter, the method  500  proceeds to block  610  wherein the controller  50  makes a determination as to whether the completed crimp conforms with the looked up pressure and the distance that was determined at block  560 . For example, the controller  50  could compare the recorded finished pressure and distance recorded at block  600  with the targeted distance and pressure determined at block  560 . 
     If these pressure and/or distance values do not compare favorably, the method  500  proceeds to block  620  where a crimp failure is indicated and then logged as a failed crimp. Alternatively, if these values do favorably match, then the method  500  proceeds to block  630  wherein a successful crimp is indicated to the user. In one arrangement, the controller  50  may store this successful crimp in memory  80  and may also be logged in a tracking log. 
     In addition, the successful crimp may be visually and/or audibly noted to a user of the power tool  100  by way of some type of human interface device: illumination of a green light emitting diode of some other user interface component  20 . Alternatively, or additionally, an operator interface may be provided along a surface of the tool housing that provides such a visual and/or graphical confirmation that the previous crimp comprises a successful crimp. This could be the same or different operator interface that the user utilized at block  510  where the user enters crimp size and connector type information prior to crimp commencement was entered into the power tool prior to crimp initiation. 
       FIGS. 8-10  depict a crimping tool head  700  according to an example embodiment of the present disclosure. As just one example, the crimping tool head or work head  700  may be utilized with a hydraulic tool as disclosed herein, such as the hydraulic tool  10  illustrated in  FIG. 1  and the hydraulic tool  130  illustrated in  FIG. 7 . Specifically,  FIG. 8  depicts a side view of the crimping tool head  700  in a closed state,  FIG. 9  depicts a side view of the crimping tool head  700  in an open state, and  FIG. 10  depicts an exploded view of the crimping tool head  700 . 
     As shown in  FIGS. 8-10 , the crimping tool head  700  includes a first frame  712  and a second frame  714 . The second frame  714  is movable relative to the first frame  712  such that the crimping tool head  700  can be (i) opened to insert one or more objects into a crimping zone  716  of the crimping tool head  700 , and (ii) closed to facilitate crimping the object(s) in the crimping zone  716 . In particular, to crimp an object and/or a work piece positioned within the crimping zone  716 , the crimping tool head  700  includes a ram  718  slidably disposed in the first frame  712  and a crimping anvil  720  on the second frame  714 . The ram  718  is movable from a proximal end  722  of the crimping zone  716  to the crimping anvil  720  at a distal end  724  of the cutting zone  716 . The ram  718  and the crimping anvil  720  can thus provide a compression force to the object(s) (e.g., metals, wires, cables, and/or other electrical connectors) positioned between the ram  718  and the crimping anvil  720  in the crimping zone  716 . 
     As shown in  FIGS. 8-10 , the ram  718  can have a shape that generally narrows in a direction from the proximal end  722  towards the distal end  724 . As such, a cross-section of a distal-most end of the ram  718  can be smaller than a cross-section of a proximal-most end of the ram  718 . As one example, the ram  718  can have a generally pyramidal shape. As another example, the ram  718  can have a plurality of sections, including one or more inwardly tapering sections  718 A and one or more cylindrical sections  718 B (see  FIG. 10 ). 
     As also shown in  FIGS. 8-10 , the crimping anvil  720  can have a shape that generally narrows in the direction from the proximal end  722  towards the distal end  724 . As examples, the crimping anvil  720  can have a generally V-shaped surface profile or a generally U-shaped surface profile. In some implementations, the shape and/or dimensions of the ram  718  can generally correspond to the shape and/or dimensions of the crimping anvil  720 , and vice versa. Due, at least in part, to the narrowing shape of the ram  718  and the crimping anvil  720 , the crimping tool head  700  can advantageously crimp object(s) with greater force over a smaller surface area than other tool heads (e.g., crimping tools having a generally flat ram and a generally flat crimping anvil). This, in turn, can help to improve electrical performance of objects coupled by the crimping operation. 
     As described above, the crimping tool head  700  can be coupled to an actuator assembly, which is configured to distally move the ram  718  to crimp the object(s) in the crimping zone  716 . For example, the actuator assembly can include a hydraulic pump, and/or an electric motor that distally moves the ram  718 . Additionally, for example, the actuator assembly can include a switch, which is operable to cause the ram  718  to move between the proximal end  722  and the distal end  724 . For instance, the switch can be movable between a first switch position and a second switch position. When the switch is in the first switch position, the actuator assembly causes the ram  718  to be in a retracted position (e.g., at the proximal end  722 ). Whereas, when the switch is in the second switch position, the actuator causes the ram  718  to move toward the crimping anvil  724  to crimp the object(s) in the crimping zone  716 . 
     Additionally, as shown in  FIGS. 8-10 , the first frame  712  has a first arm  726  and a second arm  728  extending from a base  730 . The first arm  726  is generally parallel to the second arm  728 . The first arm  726  and the second arm  728  are also generally of equivalent length. In this configuration, the first frame  712  is in the form of a clevis (i.e., U-shaped); however, the first frame  712  can have a different form in other examples. Additionally, although the first frame  712  is formed from a single piece as a unitary body in the illustrated example, the first frame  712  can be formed from multiple pieces in other examples. 
     As noted herein, the second frame  714  includes the crimping anvil  720 . In  FIGS. 8-10 , the crimping anvil  720  is integrally formed as a single piece unitary body with the second frame  714 . In an alternative example, the crimping anvil  720  can be coupled to the second frame  714 . For instance, the crimping anvil  720  can be releasably coupled to the second frame  714  via one or more first coupling members, which extend through one or more apertures in the crimping anvil  720  and the second frame  714 . By releasably coupling the crimping anvil  720  to the second frame  714 , the crimping anvil  720  can be readily replaced and/or repaired. 
     The second frame  714  is hingedly coupled to the first arm  726  at a first end  732  of the second frame  714 . In particular, the second frame  714  can rotate between a closed-frame position as shown in  FIG. 8  and an open-frame position as shown in  FIG. 9 . In the closed-frame position, the second frame  714  extends from the first arm  726  to the second arm  728  such that the crimping zone  716  is generally bounded by the ram  718 , the crimping anvil  720 , the first arm  726 , and the second arm  728 . In the open-frame position, the second frame  714  extends away from the second arm  728  to provide access to the crimping zone  716  at the distal end  724 . 
     In  FIGS. 8-10 , the second frame  714  is hingedly coupled to the first arm  726  via a first pin  734  extending through the first end  732  of the second frame  714  and a distal end portion of the first arm  726 . The distal end portion of the first arm  726  includes a plurality of prongs  736  separated by a gap, the first end  732  of the second frame  714  is disposed in the gap between the prongs  736 . This arrangement can help to improve stability and alignment of the second frame  714  relative to the first frame  712 . This in turn helps to improve alignment of the ram  718  and the crimping anvil  720  during a crimping operation. Despite these benefits, the second frame  714  can be hingedly coupled to the first arm  726  differently in other examples. 
     A second end  738  of the second frame  714  is releasably coupled to the second arm  728 , via a latch  740 , when the second frame  714  is in the closed-frame position. In general, the latch  740  is configured to rotate relative to the second arm  728  between (i) a closed-latch position in which the latch  740  can couple the second arm  728  to the second frame  714  as shown in  FIG. 8  and (ii) an open-latch position in which the latch  740  releases the second arm  728  from the second frame  714  as shown in  FIG. 9 . For example, the latch  740  can be hingedly coupled to the second arm  728  via a second pin  742 , and the latch  740  can thus rotate relative to the second arm  728  about the second pin  742 . Although  FIG. 9  shows the latch  740  in the open-latch position while the second frame  714  is in the open-frame position, the latch  740  can be in the open-latch position when the second frame  714  is in other positions. Similarly, the latch  740  can be in the closed-latch position when the second frame  714  is in the open-frame. 
     To releasably couple the latch  740  to the second frame  714 , the latch  740  and the second frame  714  include corresponding retention structures  744 A,  744 B. For example, in  FIG. 8 , the latch  740  includes a proximally-sloped bottom surface  744 A that engages a distally-sloped top surface  744 B of the second frame  714  when the latch  740  is in the closed-latch position and the second frame  714  is in the closed-frame position. The pitch of the sloped surfaces  744 A,  744 B is configured such that the surface  744 A of the latch  740  can release from the surface  744 B of the second frame  714  when the latch  740  moves to the open-latch position. Similarly, the pitch of the sloped surfaces  744 A,  744 B is configured such that the engagement between the surface  744 A and the surface  744 B prevents rotation of the second frame  714  when the second frame  714  is in the closed-frame position and the latch  740  is in the closed-latch position. 
     A release lever  746  is coupled to the latch  740  and operable to move the latch  740  from the closed-latch position to the open-latch position. For example, a proximal portion  747  of the release lever  746  can be coupled to a proximal portion  743  of the latch  740  (e.g., via a coupling member such as, for example, a screw or releasable pin). As such, the release lever  746  can be rotationally fixed relative to the latch  740 . 
     The release lever  746  also includes a projection  748  that extends from the release lever  746  towards the second arm  728  of the first frame  712 . As shown in  FIGS. 8-9 , the projection  748  can engage against the second arm  728  of the first frame  712 , when the release lever  746  is coupled to the latch  740 . In this way, the projection  748  can act as a fulcrum about which the release lever  746  can rotate. 
     In this arrangement, rotation of the release lever  746  about the projection  748  and towards the second arm  728  causes corresponding rotation of the latch  740  about the second pin  742  and away from the second frame  714 . The release lever  746  is thus operable by a user to release the second frame  714  from the latch  740  and the second arm  728  so that the second frame  714  can be moved from the closed-frame position shown in  FIG. 7  to the open-frame position shown in  FIG. 9 . 
     The latch  740  can be biased towards the closed-latch position by a biasing member. For example, the biasing member can be a spring  750  extending between the second arm  728  and the latch  740  to bias the latch  740  toward the closed-latch position.  FIG. 8  shows the spring  750  when the latch  740  is in the closed-latch position and  FIG. 9  shows the spring  750  when the latch  740  is in the open-latch position. As shown in  FIGS. 8-9 , the spring  750  extends between a first surface  752  on a proximal portion of the latch  740  and a second surface  754  on the second arm  728 . In an example, the second surface  754  can be a lateral protrusion on the second arm  728 . Because the second arm  728  is fixed and the latch  740  is rotatable, the spring  750  applies a biasing force directed from the second arm  728  to the proximal portion of the latch  740 . In this arrangement, the spring  750  thus biases the latch  740  to rotate clockwise in  FIGS. 8-9  toward the closed-latch position. 
     As shown in  FIG. 10 , the first frame  712  further includes a passage  756  extending through the base  730 . When the crimping tool head  700  is coupled to the actuator assembly, a portion of the actuator assembly can extend through the passage  756  and couple to the ram  718  in the first frame  712 . In this way, the actuator assembly can move distally through the passage  756  to thereby move the ram  718  toward the crimping anvil  720 . As one example, the ram  718  can be releasably coupled to the actuator assembly by one or more second coupling members  758  (e.g., a releasable pin or a screw). This can allow for the ram  718  to be replaced and/or repaired, and/or facilitate removably coupling the crimping tool head  700  to the actuator assembly. 
     The crimping tool head  700  can further include a return spring (such as the return spring  228  illustrated in  FIG. 3 ) configured to bias the ram  718  in the proximal direction towards the retracted position shown in  FIGS. 8-9 . The return spring can thus cause the ram  718  to return to its retracted position upon completion of a distal stroke of the ram  718  (during a crimping operation). 
       FIGS. 11A, 11B, and 11C  illustrate a hydraulic circuit  1100 , in accordance with an example implementation. Such a hydraulic circuit  1100  may be used with a hydraulic tool, such as the hydraulic crimping tool  100  illustrated in  FIG. 1  and/or the hydraulic tool  130  illustrated in  FIG. 7 . 
     The hydraulic tool  1100  includes an electric motor  1102  (shown in  FIG. 11B ) configured to drive a hydraulic pump  1104  via a gear reducer  1106 . The hydraulic tool  1100  also includes a reservoir or tank  1108 , which operates as reservoir for storing hydraulic oil at a low pressure level (e.g., atmospheric pressure or slightly higher than atmospheric pressure such as 30-70 psi). As the electric motor  1102  rotates in a first rotational direction, a pump piston  1110  reciprocates up and down. As the pump piston  1110  moves upward, fluid is withdrawn from the tank  1108 . As the pump piston  1110  moves down, the withdrawn fluid is pressurized and delivered to a pilot pressure rail  1112 . As the electric motor  1102  rotates in the first rotational direction, a shear seal valve  1114  remains closed such that a passage  1116  is disconnected from the tank  1108 . 
     The pressurized fluid in the pilot pressure rail  1112  is communicated through a check valve  1117  and a nose  1118  of a sequence valve  1119 , through a passage  1120  to a chamber  1121 . As shown in  FIG. 11C , the chamber  1121  is formed partially within the inner cylinder  1122  and partially within a ram  1124  slidably accommodated within a cylinder  1126 . The ram  1124  is configured to slide about an external surface of the inner cylinder  1122  and an inner surface of the cylinder  126 . The inner cylinder  1122  is threaded into the cylinder  1126  and is thus immovable. As show in  FIG. 11C , the pressurized fluid entering the chamber  1121  applies a pressure on the inner diameter “d 1 ” of the ram  1124 , thus causing the ram  1124  to extend (e.g., move to the left in  FIG. 11C ). A die head  1127  is coupled to the ram  1124  such that extension of the ram  1124  (i.e., motion of the ram  1124  to the left in  FIG. 11 ) within the cylinder  1126  causes a working head of the tool to move toward a working head, such as the crimper head  114  illustrated in  FIG. 1 . 
     Referring back to  FIG. 11A , the sequence valve  1119  includes a poppet  1128  that is biased toward a seat  1130  via a spring  1132 . When a pressure level of the fluid in the pilot pressure rail  1112  exceeds at threshold value set by a spring rate of the spring  1132 , the fluid pushes the poppet  1128  against the spring  1132 , thus opening a fluid path through passage  1134  to a chamber  1136 . The chamber  1136  is defined within the cylinder  1126  between an outer surface of the inner cylinder  1122  and an inner surface of the cylinder  1126 . As a result, referring to  FIG. 11C , pressurized fluid now acts on the inner diameter “d 1 ” of the ram  1124  as well as the annular area of the ram  1124  around the inner cylinder  1122 . As such, pressurized fluid now applies a pressure on an entire diameter “d 2 ” of the ram  1124 . This causes the ram  1124  to apply a larger force on an object being crimped. 
     As illustrated in  FIG. 11A , the hydraulic tool  1100  further includes a pilot/shuttle valve  1138 . The pressurized fluid in the pilot pressure rail  1112  is communicated through a nose  1140  of the pilot/shuttle valve  1138  and acts on a poppet  1142  to cause the poppet  1142  to be seated at a seat  1144  within the pilot/shuttle valve  1138 . As long as the poppet  1142  is seated at the seat  1144 , fluid flowing through the check valve  1117  is precluded from flowing through the nose  118  of the sequence valve  1119  and passage  1146  around the poppet  1144  to a tank passage  1148 , which is fluidly coupled to the tank  1108 . This way, fluid is forced to enter the chamber  1121  via the passage  1120  as described herein. 
     Further, fluid in the pilot pressure rail  1112  is allowed to flow around the pilot/shuttle valve  1138  through annular area  1149  to the passage  1116 . However, as mentioned above, when the shear seal valve  1114  is closed, the passage  1116  is blocked, and fluid communicated to the passage  1116  is precluded from flowing to the tank  1108 . 
     The crimper  1100  includes a pressure sensor (such as pressure sensor  122   FIG. 3 ) in communication with a controller of the crimper  1100 . The pressure sensor is configured to measure a pressure level within the cylinder  1126 , and provide information indicative of the measurement to the controller. As long as the measured pressure is below a threshold pressure value, the controller commands the electric motor  1102  to rotate in the first rotational direction. However, once the threshold pressure value is exceeded, the controller commands the electric motor  1102  to stop and reverse its rotational direction to a second rotational direction opposite the first rotational direction. Rotating the electric motor  1102  in the second rotational direction causes the shear seal valve  1114  to open, thus causing a fluid path to form between the pilot pressure rail  1112  through the annular area  1149  and the passage  1116  to the tank  1108 . As a result of fluid in the pilot pressure rail  1112  being allowed to flow to the tank  1108  when the shear seal valve  1114  is opened, the pressure level in the pilot pressure rail  1112  decreases. 
       FIG. 12  illustrates a close up view of the hydraulic tool  1100  showing the pilot/shuttle valve  1138 . Once the pilot pressure rail  1112  is depressurized as a result of the shear seal valve  1114  being opened, pressure level acting at a first end  1200  of the poppet  1142  is decreased. At the same time, pressurized fluid in the chamber  1121  is communicated to the passage  1146  through the nose  1118  of the sequence valve  1119  and acts on a surface area of a flange  1202  of the poppet  1142 . As such, the poppet  1142  is unseated (e.g., by being pushed downward). 
     A return spring  1150  encloses the ram  1124 , and the return spring  1150  pushes the ram  1124  (e.g., to the right in  FIGS. 11A, 11C ). As a result, fluid in the chamber  1121  is forced out of the chamber  1121  through the nose  1118  of the sequence valve  1119  to the passage  1146 , then around a nose or second end  1204  of the now unseated poppet  1142  to the tank passage  1148 , and ultimately to the tank  1108 . Similarly, fluid in the chamber  1136  is forced out of the chamber  1136  through a check valve  1152 , through the nose  1118  of the sequence valve  1119  to the passage  1146 , then around the nose or second end  1204  of the poppet  1142  to the tank passage  1148 , and ultimately to the tank  1108 . The check valve  1117  blocks flow back to the pilot pressure rail  1112 . Flow of fluid from the chambers  1121  and  1136  to the tank  1108  relieves the chambers  1121  and  1136  causing the ram  1124  to return to a start position, and the crimper  1100  is again ready for another cycle. 
     In some cases, the shear seal valve  1114  might not operate properly. In these cases, when the electric motor  1102  is commanded to rotate in the second rotational position, the shear seal valve  1114  might not open a path from the passage  1116  to the tank  1108 , and pressure level in the pilot pressure rail  1112  is not relieved and remains high. In this case, the poppet  1142  might not be unseated, and fluid in the chambers  1121  and  1136  is not relieved. As such, the ram  1124  might not return to the start position. To relieve the chambers  1121  and  1136  in the case of a failure of the shear seal valve  1114 , the hydraulic tool  1100  may be equipped with an emergency relief mechanism that is described herein. 
     As shown in  FIG. 12 , a mechanical switch or button  1206  is coupled to a poppet  1208  disposed within the pilot/shuttle valve  1138 . In an emergency or failure situation, the button  1206  may be pressed (downward), which causes the poppet  1208  to be pushed further within the pilot/shuttle valve  1138  (e.g., move downward in  FIG. 12 ). As the poppet  1208  moves, it contacts a pin  1210  that is disposed partially within the poppet  1142 . 
     The pin  1210  is in contact with a check ball  1212  disposed within the poppet  1142 . The check ball  1212  is seated at a seat  1214  within the poppet  1142  as long as the pilot pressure rail  1112  is pressurized and the poppet  1142  is seated at the seat  1144 . However, when the button  1206  is pressed and the poppet  1208  moves downward contacting and pushing the pin  1210  downward, the check ball  1212  is unseated from the seat  1214 . As a result, pressurized fluid in the pilot pressure rail  1112  is allowed to flow through the poppet  1142 , around the check ball  1212 , around the pin  1210  and the poppet  1208  to the tank passage  1148 , and ultimately to the tank  1108 . This way, the pressure in the pilot pressure rail  1112  is relieved in the case of failure of the shear seal valve  1114  via pressing the button  1206 . Relieving pressure in the pilot pressure rail  1112  allows the poppet  1142  to be unseated under pressure of fluid in the passage  1146 , thus relieving the chambers  1121  and  1136  as described above. 
     Advantageously, the configuration illustrated in  FIGS. 11 and 12  combines the operation of the emergency relief mechanism with the pilot/shuttle valve  1138  as opposed to including a separate lever mechanism and associated separate valve to allow for relieving pressure in the case of a hydraulic circuit malfunction. 
     Within some examples, the hydraulic tools  100 ,  130  can be configured such that the tool head (e.g., the tool head  114 , the crimping head  132 , the crimping tool head  700 , and/or the tool head  1418 ) is rotationally fixed relative to a frame and/or a gripping portion of a hydraulic tool (e.g., the hydraulic tools  100 ,  130 ). In other examples, the tool head can rotate relative to the frame and/or the gripping portion of the hydraulic tool. For instance, as an example,  FIG. 20  illustrates a partial cross-sectional view of a hydraulic tool  2000  including a tool head  2014  that can rotate relative to a frame  2001 . 
     As shown in  FIG. 20 , the tool head  2014  includes a first thread  2088 A that threadedly engages with a second thread  2088 B in the frame  2001 . 
     In this arrangement, the threaded engagement between the first thread  2088 A and the second thread  2088 B can define the extent to which the tool head  2014  can rotate relative to the frame  2001 . As examples, the tool head  2014  can rotate approximately 180 degrees, approximately 270 degrees, approximately 300 degrees, approximately 330 degrees, approximately 350 degrees, or approximately 360 degrees. Rotating the tool head  2014  relative to the frame  2001  can beneficially facilitate operating the hydraulic tool  2000  various operational environments (e.g., tight locations with relatively low clearance for the tool head  2014 ). 
     Also, as shown in  FIG. 20 , the hydraulic tool  2000  includes the linear distance sensor  150  described above. Given that the tool head  2014  rotates relative the frame  2001  along the threaded coupling of the first thread  2088 A and the second thread  2088 B, the tool head  2014  can move axially relative to the frame  2001  when the tool head  2014  rotates relative to the frame  2001 . Within examples, the linear distance sensor  150  can be arranged in the tool head  2014  such that the linear distance sensor  150  moves with the tool head  2014  relative to the frame  2001 . For instance, in  FIG. 20 , the linear distance sensor  150  is floated in a cavity (e.g., the cylindrical bushing  126  shown in  FIG. 3 ) of the tool head  2014  and biased by a spring  2090  into contact with the tool head  2014  as the tool head  2014  translates away from the frame  2001 . Stated differently, the spring  2090  biases the linear distance sensor  150  in a direction from the frame  2001  toward the tool head  2014  such that the linear distance sensor  150  maintains a fixed position in the tool head  2014  when the tool head  2014  moves axially during rotation of the tool head  2014  relative to the frame  2001 . In this arrangement, the linear distance sensor  150  can accurately sense the linear distance in all rotational alignments between the tool head  2014  and the frame  2001 . 
     In some examples, the tool head  2014  can include one or more wires  2092  that extend from a location internal to the tool head  2014  into the frame  2001 . In one example, the wire(s)  2092  can extend from the linear distance sensor  150  in the tool head  2014  and through the frame  2001  to the controller  50  (in  FIG. 2 ). In  FIG. 20 , the wire(s)  2092  are routed out a proximal end  2096  of the tool head  2014  along a direction substantially parallel to the central axis of the hydraulic tool  200 . Further, in  FIG. 20 , the wire(s)  2092  do not route radially outwardly until the wire(s)  2092  are past the proximal end  2096  of the tool head  2014  and into the frame  2001  (e.g., into a plurality of handle halves  2094  of the frame  2001 ). This arrangement can allow the tool head  2014  to rotate relative to the frame  2001  without a slip ring contact for the wire(s)  2092 . However, in other examples, the hydraulic tool  2000  can include a slip ring contact for electrically coupling to the wire(s)  2092  extending from the tool head  2014 . 
     As described above, the hydraulic tools  100 ,  130  can be operated based, at least in part, on sensor information provided by the pressure sensor  122  and/or the distance sensor  150  to the controller  50 . For instance, among other things, the controller  50  can determine when to stop the motor  102  based on the sensor information provided by the distance sensor  150  and/or the pressure sensor  122 . In one implementation, the controller  50  can stop the motor  102  responsive to the controller  50  determining, based on a signal from the pressure sensor  122 , that a maximum fluid pressure was sensed by the pressure sensor  122 . Additionally or alternatively, the controller  50  can stop the motor  102  responsive to the controller  50  determining, based on a signal from the distance sensor  150 , that the piston  200  traveled a certain distance. 
     According to further example embodiments, a hydraulic tool (such as, e.g., the tools  100 ,  130  described above) can include additional or alternative sensors, which can provide additional or alternative types of sensor information to facilitate the controller  50  operating the tool  100 ,  130 . 
     As one example,  FIG. 14  depicts a simplified block diagram of a hydraulic tool  1400  according to another example embodiment. The hydraulic tool  1400  can include and/or omit any of the components of the hydraulic tool  100  and the hydraulic tool  130  described above. For instance, as shown in  FIG. 14 , the hydraulic tool  1400  includes the motor  102 , the gear reducer  106 , the pump  104 , the fluid reservoir  214 , the pressure sensor  122 , the moveable piston  200 , the distance sensor  150 , the controller  50 , and the user interface  136 , which can be arranged and operate as described above for the hydraulic tool  100  and/or the hydraulic tool  130  described above. 
     Also, as shown in  FIG. 14 , a tool head  1418  has a plurality of jaws  1416 , which can move relative to each other to perform work on a workpiece located between the jaws  1416 . In  FIG. 14 , the jaws  1416  include a first jaw  1416 A and a second jaw  1416 B. However, in other examples, the jaws  1416  can include a greater quantity of jaws  1416 . 
     In one example, the tool head  1418  is in the form of a cutting head. In an implementation of such example, the jaws  1416  can include a first blade and a second blade for cutting a workpiece located between the first blade and the second blade. 
     In another example, the tool head  1418  is in the form of a crimping head such as, for example, the crimping heads  114 ,  132 , and  700  described above. In one implementation, the tool head  1418  can be a die-less crimping head. For instance, the jaws  1416  can include a ram and an anvil for crimping a workpiece. In another implementation, the tool head  1418  can be a crimping head having a first crimping die and a second crimping die for crimping the workpiece. 
     Within examples, the jaws  1416  can open and close to perform work on the workpiece such as cutting and/or crimping the workpiece. More specifically, the piston  200  can move at least one of the jaws  1416  towards another of the jaws  1416  until the jaws  1416  reach a closed position. In an example in which the tool head  1418  is a cutting head with a first blade and a second blade, the jaws  1416  can complete a cut of the workpiece when the jaws  1416  are at the closed position. In another example, in which the tool head  1418  is a crimping head, the jaws  1416  can complete a crimp of the workpiece when the jaws  1416  are at the closed position. More generally, the closed position can be a position in which the jaws  1416  are at a minimum distance relative to each other. In one embodiment, the closed position is indicated by the pressure exceeding a predetermined upper pressure. In another embodiment, the closed position is indicated by the motor current exceeding a predetermined upper current. In another embodiment, the closed position is at a distance between the jaws suitable for achieving a good crimp based on the type and size of the workpiece. 
     As shown in  FIG. 14 , the hydraulic tool  1400  further includes a position sensor  1462  coupled to the tool head  1418  and in communication with the controller  50 . The position sensor  1462  can detect when the jaws  1416  are at the closed position and responsively generate a sensor signal indicating to the controller  50  that the jaws  1416  are at the closed position. As examples, the position sensor  1462  can include a contact switch (e.g., a momentary spring-biased switch), a magnetic switch (e.g., a reed switch), a Hall-Effect sensor, and/or a piezoelectric device. Additionally, for instance, the position sensor  1462  can include a normally-closed and/or a normally-open switch. 
     Within examples, the position sensor  1462  can include a first sensor portion  1462 A and a second sensor portion  1462 B, which can interact with the first sensor portion  1462 A in a fixed and consistent manner when the jaws  1416  are in the closed position. For instance, in some examples, the first sensor portion  1462 A and the second sensor portion  1462 B can be configured to physically contact each other when the jaws  1416  are in the closed position, and be physically spaced apart from each other when the jaws  1416  are not in the closed position. In other examples, the first sensor portion  1462 A and the second sensor portion  1462 B can always be at a specific distance from each other when the jaws  1416  are in the closed position, and at other distances from each other when the jaws  1416  are not in the closed position. 
     More generally, the position sensor  1462  can be arranged with the tool head  1418  such that (i) the first sensor portion  1462 A and the second sensor portion  1462 B are only at a predetermined location relative to each other (e.g., in contact or at a specific distance) when the jaws  1416  are in the closed position, and (ii) the interaction between the first sensor portion  1462 A and the second sensor portion  1462 B at the predetermined location causes the position sensor  1462  to provide the sensor signal to the controller  50  indicating that the jaws  1416  are at the closed position. 
     Within examples, a first part of the tool head  1418  can include the first sensor portion  1462 A and a second part of the tool head  1418  can include the second sensor portion  1462 B. The first part of the tool head  1418  and the second part of the tool head  1418  can move relative to each other such that the first sensor portion  1462 A and the second sensor portion  1462 B are (i) at the predetermined location relative to each other when the jaws  1416  are in the closed position and (ii) at other locations relative to each other when the jaws  1416  are not at the closed position. 
     For instance, in an example, the first jaw  1416 A can include the first sensor portion  1462 A and the second jaw  1416 B can include the second sensor portion  1462 B. In another example, one of the jaws  1416  can include the first sensor portion  1462 A, and a frame or another stationary feature of the tool head  1418  can include the second sensor portion  1462 B. 
     In one implementation, the first sensor portion  1462 A can include a contact switch (e.g., a momentary spring-biased switch), which the second sensor portion  1462 B actuates when the jaws  1416  are in the closed position. In another implementation, the first sensor portion  1462 A can include a magnetic switch and/or Hall-Effect sensor. The second sensor portion  1462 B can include a magnetic element, which applies a magnetic field of threshold-strong strength to the first sensor portion  1462 A when the magnetic element is at the predetermined location relative to the first sensor portion  1462 A. Responsive to the first sensor portion  1462 A sensing the threshold-strong strength, the first sensor portion  1462 A transmits the sensor signal to the controller  50 . 
     In yet another implementation, the first sensor portion  1462 A and the second sensor portion  1462 B can be conductors that contact each other to form a completed circuit. For instance, the first jaw  1416 A can include the first sensor portion  1462 A and the second jaw  1416 B can include the second sensor portion  1462 B. In this arrangement, when the first jaw  1416 A contacts the second jaw  1416 B, the position sensor  1462  can detect an electrical signal (e.g., a change in current, an inductance, and/or resistance) due the conductive coupling of the first jaw  1416 A and the second jaw  1416 B. 
     As noted above, the controller  50  can receive the sensor signal from the position sensor  1462  and, based on the sensor signal, determine when the jaws  1416  are in the closed position. Accordingly, whereas the controller  50  can infer that the jaws  1416  are in the closed position based on the sensor information provided by the pressure sensor  122  and/or the distance sensor  150 , the controller  50  can directly determine when the jaws  1416  are in the closed position from the sensor information provided by the position sensor  1462 . Accordingly, the controller  50  can directly determine that a crimp or a cut of a workpiece by the jaws  1416  has been completed based on the sensor information provided by the position sensor  1462 . 
     Within examples, the controller  50  can operate the motor  102  based, at least in part, on the sensor signal received from the position sensor  1462 . For instance, during a crimping operation and/or a cutting operation, the controller  50  can cause the motor  102  to run so as to close the jaws  1416  until the controller  50  receives the sensor signal from the position sensor  1462  indicating that the jaws  1416  are in the closed position. Responsive to the controller  50  receiving the sensor signal from the position sensor  1462  indicating that the jaws  1416  are in the closed position, the controller  50  can cause the motor  102  to stop. The controller  50  can then run the motor  102  to open jaws  1416  so that a next crimping operation and/or a next cutting operation can be performed by the hydraulic tool  1400 . 
     By stopping the motor  102  responsive to the position sensor  1462  indicating that the jaws  1416  are in the closed position, the controller  50  can beneficially stop the motor  102  more rapidly than in examples in which the controller  50  stops the motor based on the pressure sensor  1422  detecting a maximum pressure (which may not occur until after the jaws  1416  reach the closed position). This can thus provide for greater operational efficiencies and/or less wear on the components of the hydraulic tool  1400  (e.g., the motor  102 , the gear reducer  106 , the pump  104 , and/or the piston  108 ). 
     In an additional or alternative example, the process  300  described and illustrated with respect to  FIG. 5  can be modified such that the controller  50  determines when to stop the motor at block  370  based on sensor information provided by the position sensor  1462  instead of and/or in addition to the sensor information provided by the pressure sensor  122  and/or the distance sensor  150 . 
     A flowchart for a process  300 ′ in accordance with one implementation of such an example is depicted in  FIG. 15 . As shown in  FIG. 15 , the process  300 ′ is substantially the same as the process  300  shown in  FIG. 5 , except the steps at blocks  350  and  360  are replaced with a step at block  1550 . At block  1550 , the process  300 ′ includes determining whether the position sensor  1462  has indicated that the jaws  1416  are in the closed position. If the position sensor  1462  has not indicated that the jaws  1416  are in the closed position at block  1550 , then the process  300 ′ can return to block  340 . Whereas, if the position sensor  1462  has indicated that the jaws  1416  are in the closed position at block  1550 , then the process can proceed to block  370 . 
     Also, in an additional or alternative example, the process  500  described and illustrated with respect to  FIG. 6  can be modified such that the controller  50  determines when to stop the motor at block  590  based on sensor information provided by the position sensor instead of and/or in addition to the sensor information provided by the pressure sensor  122  and/or the distance sensor  150 . 
     A flowchart for a process  500 ′ in accordance with one implementation of such an example is depicted in  FIG. 16 . As shown in  FIG. 16 , the process  500 ′ is substantially the same as the process  500  shown in  FIG. 6 , except the steps at blocks  570  and  580  are replaced with a step at block  1670 . At block  1670 , the process  500 ′ includes determining whether the position sensor  1462  has indicated that the jaws  1416  are in the closed position. If the position sensor  1462  has not indicated that the jaws  1416  are in the closed position at block  1670 , then the process  500 ′ can return to start of block  1670 . Whereas, if the position sensor  1462  has indicated that the jaws  1416  are in the closed position at block  1670 , then the process can proceed to block  590 . 
     In additional or alternative examples, the controller  50  can operate the motor  102  based, at least in part, on the sensor information provided by the position sensor  1462  to partially retract the piston  200  while performing work on a plurality of similar workpieces. In such examples, responsive to the position sensor  1462  indicating that the jaws  1416  are in the closed position, the controller  50  operates the motor  102  to pull back the piston  200  to the partially retracted position. The partially retracted position of the piston  200  can be a position at which an opening between the jaws  1416  is slightly larger than a circumference of the workpieces. As the piston  200  does not fully retract before initiating a crimp and/or cut of the next workpiece, the hydraulic tool  1400  can more rapidly complete work on a plurality of similar workpieces. 
       FIG. 17  depicts a flowchart for a method  1700  for using the hydraulic tool  1400  to perform work on a plurality of similar workpieces, according to an example embodiment. As shown in  FIG. 17 , at block  1710 , the method  1500  includes determining whether a tool trigger (e.g., the tool trigger  138  in  FIG. 7 ) has been pulled. If it is determined at block  1710  that the tool trigger has not been pulled, then the method  1700  returns to the start of block  1710 . 
     If it is determined at block  1710  that the tool trigger has been pulled, then a crimping and/or cutting action commences. That is, the method  1700  proceeds to block  1712  at which the controller  50  initiates activation of the motor  102 . After the motor  102  has been activated at block  1712 , the pressure sensor  122  senses the pressure of the fluid, which begins to increase as the piston  200  moves and the jaws  1416  close. 
     At block  1714 , the method  1700  includes determining, based on the sensor information provided by the pressure sensor  122 , whether the pressure of the fluid is greater than a threshold. The threshold can relate to an amount of pressure indicating that the jaws  1416  first contacted the workpiece (i.e., contacted an outer surface of the workpiece). 
     If it is determined at block  1714  that the pressure is not greater than the threshold, then the method  1700  returns to the start of block  1714 . If it is determined at block  1714  that the pressure is greater than the threshold, then the method  1700  proceeds to block  1716  at which a distance of the piston  200  sensed by the distance sensor  150  is recorded in the memory. Specifically, the distance recorded at block  1716  can relate to the position of the piston  200  at the point at which the pressure sensor  122  sensed the pressure greater than the threshold. In this way, the controller  50  can determine an indication of the circumference of the workpiece as described above. 
     At block  1718 , the method  1700  includes determining whether the jaws  1416  are in the closed position based on the sensor signal provided from the position sensor  1462  to the controller  50 . If it is determined that the jaws  1416  are not in the closed position at block  1718 , then the method  1700  returns to the start of block  1718 . If it is determined that the jaws  1416  are in the closed position based on the sensor signal provided by the position sensor  1462  at block  1718 , then the controller  50  stops the motor  102  at block  1720 . Additionally, the controller  50  can determine that the crimping and/or cutting action was completed responsive to the position sensor  1462  indicating that the jaws  1416  are in the closed position. 
     At block  1722 , the controller  50  operates the motor  102  to open the jaws  1416  at block  1716 . At block  1724 , the method  1700  includes determining whether the piston  200  is at the partially retracted position, which is based on the distance recorded at block  1716 . The partially retracted position is reached by the piston  200  prior to reaching the fully retracted position of the piston  200  (e.g., the home position of the piston  200 ). Specifically, the partially retracted position can provide for the jaws  1416  opening to an extent, which allows for a next workpiece to be positioned between the jaws  1416  without fully retracting the piston  200 . This can be achieved by moving the piston  200  to a position slightly past the position at which the controller  50  determined that the jaws  1416  first contacted the workpiece (i.e., at block  1714 ). As the piston  200  does not fully retract before initiating a crimp and/or cut of the next workpiece, the hydraulic tool  1400  can more rapidly operate on a plurality of similar workpieces. 
     At block  1726 , the method  1700  includes running the motor to carry out the next crimp and/or cut of the next workpiece. The process then returns to block  1718  and repeats. 
     In an additional or alternative example, the controller  50  can receive the sensor signal from the position sensor  1462  indicating that the jaws  1416  are at the closed position, and responsively provide an output to an operator to indicate that a cutting and/or crimping operation is completed. In one implementation, this can beneficially facilitate a remote cutting operation by the hydraulic tool  1400 . 
     In examples, electrical equipment may be maintained while operating at high voltages. An example maintenance operation may involve cutting a live line. In this example, it may be desirable to perform a cable cutting operation by way of a remotely controlled cutting tool so as to insulate workers from electrical hazards. 
     In other examples, the line might not be easily reachable. For instance, the cable may be in an underwater environment, and may thus be cut via remote control of the cutting tool. 
       FIG. 18  depicts a simplified block diagram of a remotely-controlled hydraulic tool  1800  according to another example embodiment. As shown in  FIG. 18 , the hydraulic tool  1800  is substantially the same as the hydraulic tools  100 ,  130 ,  1400  described above. For example, as described above, the hydraulic tool  1800  includes the motor  102 , the gear reducer  106 , the pump  104 , the fluid reservoir  214 , the pressure sensor  122 , the moveable piston  200 , the distance sensor  150 , the controller  50 , the user interface  136 , the jaws  1416 , and the position sensor  1462 , which can be arranged and operate as described above for the hydraulic tool  1400 , the hydraulic tool  100  and/or the hydraulic tool  130  described above. 
     Additionally, as shown in  FIG. 18 , the hydraulic tool  1800  includes a remote controller  1866  in communication with the controller  50 . The remote controller  1866  includes a user input device  1868 , which is actuatable to provide a trigger signal from the remote controller  1866  to the controller  50  to cause the motor  102  to move the piston  200  and thereby move the jaws  1416  toward the closed position. In this way, the user input device  1868  is actuatable to initiate a cutting operation at a safe distance away from the tool head  1418  and/or the workpiece (e.g., a live wire or cable). 
     The remote controller  1866  also includes an output device  1870 . The output device  1870  is also in communication with the controller  50 . The controller  50  can transmit a signal to the output device  1870  to indicate when the cutting operation is completed. Specifically, the controller  50  can (i) receive the sensor signal from the position sensor  1462 , (ii) determine that the jaws  1416  are in the closed position based on the sensor signal, and (iii) responsive to determining that the jaws  1416  are in the closed position, transmit the signal to the output device  1870  to indicate that the jaws  1416  are in the closed position and the cutting operation is completed. 
     Within examples, the output device  1870  can be configured to provide the user with a visual indication and/or an auditory indication that the jaws  1416  are in the closed position and/or the cutting operation is completed. For instance, the output device  1870  can include an indicator light, a display screen, and/or a speaker to provide the indication(s) to the user. 
     As noted above, the position sensor  1416  can directly indicate that the jaws  1416  reached the closed position and, thus, the position sensor  1416  can provide a reliable indication that the cutting operation was completed. Accordingly, in an environment in which live wires are to be cut, the indication provided to the user based on sensor information sensed by the position sensor  1416  can beneficially facilitate safe operation of the hydraulic tool  1800  at remote distances. 
     Referring now to  FIG. 19 , a simplified block diagram of a hydraulic tool  1900  is depicted according to another example embodiment. As shown in  FIG. 19 , the hydraulic tool  1900  is substantially the same as the hydraulic tools  100 ,  130 ,  1400 ,  1800  described above. For example, as described above, the hydraulic tool  1900  includes the motor  102 , the gear reducer  106 , the pump  104 , the fluid reservoir  214 , the pressure sensor  122 , the moveable piston  200 , the distance sensor  150 , the controller  50 , the user interface  136 , the battery  212 , the jaws  1416 , and the position sensor  1462 , which can be arranged and operate as described above for the hydraulic tool  1400 , the hydraulic tool  1800 , the hydraulic tool  100  and/or the hydraulic tool  130  described above. 
     Additionally, as shown in  FIG. 19 , the hydraulic tool  1900  includes a plurality of additional sensors  1980 ,  1982 ,  1984 ,  1986 ,  1988  in communication with the controller  50  and configured to sense various conditions associated with operation of the hydraulic tool  1900  during a crimping operation. In particular, the hydraulic tool  1900  includes a first current sensor  1980 , which is operable to sense a current draw at the battery  212 . The hydraulic tool  1900  also includes a motor speed sensor  1982 , which is operable to sense a speed at which the motor  102  is operating. The hydraulic tool  1900  further includes a second current sensor  1984 , which is operable to sense a current draw at the motor  102 . Additionally, the hydraulic tool  1900  includes a timer  1986 , which is operable to sense and indicate time during operation of the hydraulic tool  1900 . The hydraulic tool  1900  can also include a strain gauge  1988 , which is operable to sense a force imparted by at least one jaw  1416  on at least one other jaw  1416 . 
     In this arrangement, the controller  50  can receive, over a stroke of the piston  200 , sensor information from the pressure sensor  122 , the distance sensor  150 , the position sensor  1462 , the first current sensor  1980 , the motor speed sensor  1982 , the second current sensor  1984 , the timer  1986 , and/or the strain gauge  1988 . Based on the received sensor information, the controller  50  can determine a crimp profile over the stroke of the piston  200 . 
     For example, for a particular type of connector, the pressure sensed by the pressure sensor  122  has a particular shape over the distance of the piston  200  stroke sensed by the distance sensor  150  and/or the time sensed by the timer  1986 . Additionally or alternatively, for example, the motor speed sensed by the motor speed sensor  1982 , the current draw sensed by the first current senor  1980 , and/or the current draw sensed by the second current sensor  1984  each have a respective shape over the distance sensed by the distance sensor  150  and/or the time sensed by the timer  1986 . 
     Based on the crimp profile(s) determined by the controller  50 , the controller  50  can determine at least one characteristic of a crimp performed on a workpiece. As examples, the characteristic(s) of the crimp performed on the workpiece can include (i) an identification of an event during a stoke of the piston  200 , (ii) an identification of a type of connector for the workpiece on which the crimp was performed, and/or (iii) a determination as to whether the crimp was successfully or unsuccessfully performed on the workpiece. 
     As examples, based on the crimp profile(s), the controller  50  can determine, for instance, a time and/or a distance of the piston  200  at which the following events occur during a stoke: initiation of the crimp stroke, a first contact with the workpiece, a fluid pressure at the first contact with the work piece, a current draw at the battery and/or the motor at the first contact with the workpiece, a minimum fluid pressure sensed during the stroke, a maximum fluid pressure sensed during the stroke, a duration of the stroke, a rate of change of the current draw, a rate of change of the fluid pressure, the jaws  1416  reached the closed position, a fluid pressure when the jaws  1416  reached the closed position, and/or a current draw when the jaws  1416  reach the closed position. Other example events are also possible. 
     As noted above, the controller  50  can additionally or alternatively determine the connecter type based on the crimp profile(s). For example, the controller  50  can store in the memory  80  data relating to a plurality of reference crimp profiles that are each expected for a respective one of a plurality of different types of connectors. In this example, the controller  50  can perform a comparison of the crimp profile(s) determined by the controller  50  based on the sensor information received during the stroke to the reference crimp profile stored in the memory  80 . Based on the comparison, the controller  50  can determine that a particular reference crimp profile matches the crimp profile determined based on the sensor information during the stroke (e.g., based on a confidence score and/or best-fit analysis). The controller  50  can then determine that the workpiece was a particular type of connector associated with the matching reference crimp profile in the memory  80 . 
     In an additional or alternative example, prior to crimping the workpiece, the controller  50  can receive information related to a desired crimp and/or a type of connector for the workpiece via the user interface  136  (e.g., as described above with respect to block  310  of  FIG. 5 ). Based on the entered information, the controller  50  can determine one or more reference crimp profiles (e.g., by looking up the reference crimp profile(s) in the memory  80 ). Then during and/or after the crimping operation, the controller  50  can compare the crimp profile(s) determined by the controller  50  based on the sensor information received during the stroke to the reference crimp profile(s). Based on the comparison, the controller  50  can identify one or more events that occurred during the stroke and/or whether the crimping operation was successful. 
     In some examples, the controller  50  can determine whether the crimping operation was successful or unsuccessful based on whether and to what extent the crimp profile(s) determined based on the sensor information match the reference(s) crimp profiles determined based on the user input. Specifically, the controller  50  can determine that the crimping operation was successful when the crimp profile(s) determined based on the sensor information match the reference crimp profile(s) (and/or are within a threshold tolerance range of each other over the stroke). Whereas, the controller  50  can determine that the crimping operation was unsuccessful when the crimp profile(s) do not match the reference(s) crimp profile(s) (and/or are outside the threshold tolerance range of each other over the stroke). 
     In other examples, the controller  50  can additionally or alternatively determine a quality of crimp indicator by comparing the sensor information with one or more threshold values. For instance, in one example, the pressure sensor  122  can provide to the controller  50  the sensor information indicative of a sensed pressure of the fluid when the ram  208 ,  718 ,  1124  is extended to a target location and/or extended by a target distance from a retracted position (e.g., as measured by the linear distance sensor  150 ). The controller  50  can then compare the sensed pressure to a predetermined threshold pressure level. If the controller  50  determines that the sensed pressure is less than the predetermined threshold pressure level, the controller  50  can indicate that the crimp was bad. Otherwise, if the controller  50  determines that the sensed pressure is approximately equal to or greater than the predetermined threshold pressure level, the controller  50  can indicate that the crimp was good. 
     In another example, the current sensor  1980  can provide to the controller  50  the sensor information indicative of a sensed current drawn by the hydraulic tool  1400  from the battery  212  when the ram  208 ,  718 ,  1124  is extended to the target location and/or extended by the target distance (e.g., as measured by the linear distance sensor  150 ). The controller  50  can then compare the sensed current to a predetermined threshold current level. If the controller  50  determines that the sensed current is less than the predetermined threshold current level, the controller  50  can indicate that the crimp was bad. Otherwise, if the controller  50  determines that the sensed current is approximately equal to or greater than the predetermined threshold current level, the controller  50  can indicate that the crimp was good. 
     In another example, the linear distance sensor  150  and the timer  1986  can provide to the controller  50  the sensor information indicative of a sensed velocity and/or a sensed acceleration of the ram  208 ,  718 ,  1124  when the ram  208 ,  718 ,  1124  is extended to the target location and/or extended by the target distance (e.g., as measured by the linear distance sensor  150 ). The controller  50  can then compare the sensed velocity and/or sensed acceleration to a predetermined threshold velocity level and/or a predetermined threshold acceleration level. If the controller  50  determines that the sensed velocity and/or the sensed acceleration are less than the predetermined threshold velocity level and/or the predetermined threshold acceleration level, respectively, the controller  50  can indicate that the crimp was bad. Otherwise, the controller  50  can indicate that the crimp was good. 
     In another example, the motor speed sensor  1982  (e.g., a Hall-Effect sensor) can provide to the controller  50  the sensor information indicative of a sensed rotational speed of the motor  102  when the ram  208 ,  718 ,  1124  is extended to the target location and/or extended by the target distance (e.g., as measured by the linear distance sensor  150 ). The controller  50  can then compare the sensed rotational speed to a predetermined threshold speed level. If the controller  50  determines that the sensed rotational speed is less than the predetermined threshold speed level, the controller  50  can indicate that the crimp was bad. Otherwise, if the controller  50  determines that the sensed rotational speed is approximately equal to or greater than the predetermined threshold speed level, the controller  50  can indicate that the crimp was good. 
     In another example, the strain gauge  1988  can provide to the controller  50  the sensor information indicative of a sensed strain on the jaws  1416  when the ram  208 ,  718 ,  1124  is extended to the target location and/or extended by the target distance (e.g., as measured by the linear distance sensor  150 ). The controller  50  can then compare the sensed strain to a predetermined threshold strain level. If the controller  50  determines that the sensed strain is less than the predetermined threshold strain level, the controller  50  can indicate that the crimp was bad. Otherwise, if the controller  50  determines that the sensed strain is approximately equal to or greater than the predetermined threshold strain level, the controller  50  can indicate that the crimp was good. 
     As described above, the controller  50  can determine the crimp quality indicator based on a comparison of the sensor information with one or more threshold values. In the examples described above, the controller  50  can compare a sensed value with a predetermined threshold value. In some implementations, the predetermined threshold value can be a single value. In other implementations, one or more of the predetermined threshold values can be a range of threshold values such that the comparison involves determining whether the sensed value falls in or out of the range of threshold values. 
     Also, in the examples described above, the controller  50  determines the crimp quality indicator based on sensor information corresponding to conditions existing at the time when the ram  208 ,  718 ,  1124  is extended to the target location and/or extended by the target distance. However, in other examples, the controller  50  can additionally or alternatively determine the crimp quality indicator based on sensor information corresponding to conditions existing other times. For instance, in one implementation, the controller  50  can determine a crimp quality indicator based on sensor information corresponding to conditions existing at a moment when the tool head  1418  deforms the connector (e.g., while applying a pressure to the connector that is less than approximately 400 pounds per square inch). 
     In another implementation, for instance, the controller  50  can determine a crimp quality indicator based on sensor information corresponding to conditions existing prior to the tool head  1418  deforming the connector (e.g., a sensed distance and a sensed pressure at a low-force stage of a crimp operation). Further, in an embodiment of this implementation, the controller  50  can cause the ram  208 ,  718 ,  1124  to accelerate responsive to and based on the crimp quality indicator. 
     Accordingly, the controller  50  can be configured to receive a variety of different types of sensor information from a plurality of the sensors, correlate the different types of sensor information, and detect (or infer) various conditions about the workpiece and/or the crimp performed. As further examples, the controller  50  can determine, based on the crimp profile(s), a type and/or size of a connector, whether the user crimped a type of connector that was different than expected for the stroke, and/or whether the user performed the crimp at the wrong position on the workpiece (e.g., off-center). 
     In the examples described above, the controller  50  can determine a crimp profile based on the sensor information received from various sensors of the hydraulic tool  1900 . Thus, in the examples described above, the tool head  1418  can be crimping tool head for performing the crimping operation. In additional or alternative examples, the tool head  1418  can include one or more blades for performing a wire stripping and/or cutting operation. In such examples, the principles described above with respect to the crimping operations can be extended to apply to wire stripping and/or cutting operations. For instance, the controller  50  can determine a stripping profile and/or a cut profile based on the sensor information received from the sensors. Similarly, the controller  50  can compare the stripping profile and/or cut profile to corresponding reference profiles to determine similar characteristics of the stripping and/or cutting operations described above. 
     Additionally, in  FIG. 19 , the hydraulic tool  1900  includes the sensors  122 ,  150 ,  1462 ,  1980 ,  1982 ,  1984 , and/or  1986  described above. However, in other examples, the hydraulic tool  1900  can omit one or more of the sensors  122 ,  150 ,  1462 ,  1980 ,  1982 ,  1984 , and/or  1986 , and/or the hydraulic tool  1900  can include other sensors not shown in  FIG. 19 . 
     The description of the different advantageous embodiments has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments in the form disclosed. Modifications and variations will be apparent to those of ordinary skill in the art. Further, different advantageous embodiments may provide different advantages as compared to other advantageous embodiments. The embodiment or embodiments selected are chosen and described in order to best explain the principles of the embodiments, the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.