Patent Publication Number: US-2019176208-A1

Title: Crimping monitoring system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/336,103, filed on May 13, 2016, the disclosure of which is hereby incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to crimping, electrical terminals, crimping electrical terminals, and methods of monitoring crimping. 
     BACKGROUND 
     This background description is set forth below for the purpose of providing context only. Therefore, any aspects of this background description, to the extent that it does not otherwise qualify as prior art, is neither expressly nor impliedly admitted as prior art against the instant disclosure. 
     Electrical terminals are often connected to electrical conductors, such as wires, via mechanical processes. Such mechanical processes, which may include crimping, may be difficult to conduct consistently, so it may be desirable to monitor the crimping to evaluate the quality of crimped connections. Crimping may also be applied to non-electrical applications (e.g., tubing, piping, etc.). 
     There is therefore a desire for solutions/options that address, minimize, or eliminate one or more of the above-described challenges. The foregoing discussion is intended only to illustrate examples of the present field and should not be taken as a disavowal of scope. 
     SUMMARY 
     In embodiments, a crimping monitoring system may include a sensor configured for electrical connection with at least one of a first element and a second element, and a crimping device including a first crimping fixture and a second crimping fixture. The crimping device may be configured to crimp said first element and said second element together. The sensor may be configured to monitor an electrical characteristic of at least one of said first element and said second element during crimping of said first element and said second element together. The first element may include an electrical terminal and the second element may include a conductor. The sensor may be configured for indirect connection with at least one of the terminal and the conductor via at least one of the first crimping fixture and the second crimping fixture. One of the first element and the second element may not be electrically conductive. 
     With embodiments, in a non-crimping position, the first crimping fixture may be electrically isolated from a remainder of the crimping device and may be electrically connected (e.g., directly) to an electrical ground. The first crimping fixture may include a punch and the second crimping fixture may include an anvil. A crimping device may be configured such that, in a non-crimping position of the first crimping fixture and the second crimping fixture, an electrical current from a current source may flow via a first path to an electrical ground, and in a crimping position of the first crimping fixture and the second crimping fixture, the electrical current from the current source may flow via the first path and a second path. In the non-crimping position, current may not flow via the second path. The second path may include an interface of the first element and second element and a sense resistor of the sensor. 
     In embodiments, the crimping device may include an applicator supporting at least one of the first crimping fixture and the second crimping fixture. The crimping device may include an actuator configured to actuate at least one of the first crimping fixture and the second crimping fixture, and an electrical connector connecting the applicator with the actuator. The system may include an electronic controller connected to the sensor. At least one of the electronic controller and the sensor may be configured to compensate for a resistance the crimping device. 
     With embodiments, a method of monitoring crimping may include disposing a first member in contact with a second member, sensing an initial value of an electrical characteristic of at least one of the first member and the second member via an electrical characteristic sensor, crimping the first member with the second member to form a crimped member, sensing a first change in the electrical characteristic, reducing a crimping force, and/or sensing a second change in the electrical characteristic after reducing the crimping force. The method may include determining a quality of the crimped member via comparing the second change to a predetermined value or range. The electrical characteristic may include a voltage drop. The first member may include an electrical terminal and the second member may include a conductor. The first change may include a decrease and the second change may include an increase. 
     In embodiments, a method of monitoring crimping may include monitoring the electrical characteristic during the crimping and continuing crimping until the electrical characteristic maintains a stable value. Crimping may include applying a compression force to at least one of the first member and the second member via at least one of a first fixture of a crimping device and a second fixture of said crimping device. The method may include obtaining an initial value of an electrical characteristic of a crimping device. The method may include determining a quality of the crimped member, wherein determining said quality includes compensating for an initial value of an electrical characteristic of a crimping device. 
     The foregoing and other aspects, features, details, utilities, and advantages of the present disclosure will be apparent from reading the following description, and from reviewing the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of an electrical terminal. 
         FIG. 2  is a perspective view of an electrical terminal and a crimping monitoring system according to embodiments of the present disclosure. 
         FIG. 3A  is a schematic of a crimping monitoring system according to embodiments of the present disclosure. 
         FIG. 3B  is a schematic of a crimping monitoring system according to embodiments of the present disclosure. 
         FIG. 4  is a graph generally illustrating a voltage drop across a crimped connection according to embodiments of the present disclosure. 
         FIG. 5  is a graph generally illustrating a voltage drop across a crimped connection according to embodiments of the present disclosure. 
         FIG. 6  is a graph generally illustrating a voltage drop across a crimped connection relative to time and of a crimping force relative to time according to embodiments of the present disclosure. 
         FIG. 7  is a combined schematic and side view of a crimping monitoring system generally illustrating embodiments of the present disclosure. 
         FIG. 8  is a combined schematic and side view of a crimping monitoring system according to embodiments of the present disclosure. 
         FIG. 9  is a flow diagram of a method of monitoring crimping according to embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments of the present disclosure, examples of which are described herein and illustrated in the accompanying drawings. While the disclosure will be described in conjunction with embodiments and/or examples, it will be understood that they are not intended to limit the present disclosure to these embodiments and/or examples. On the contrary, the present disclosure is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the present disclosure. 
     As generally illustrated in  FIGS. 1 and 2 , in embodiments, a first element (e.g., electrical terminal  10  and/or electrical terminal  12 ) may be crimped to one or more second elements (e.g., electrical conductor  20 , which may include a wire). A first element may be referred to herein as terminal  10  and/or as terminal  12 , but is not limited to a terminal. Second elements may be referred to herein as conductors  20 , but are not limited to conductors or conducting materials. Crimping may, for example, include applying one or more forces F to certain portions  14 ,  16  of a terminal  12  such that the terminal portions  14 ,  16  connect to (e.g., clamp on) a portion of conductor  20  and may limit and/or prevent relative movement between terminal  12  and conductor  20 . Additionally or alternatively, crimping may provide and/or improve an electrical connection between a terminal  10 ,  12  and conductor  20 . 
     In embodiments, such as generally illustrated in  FIGS. 2, 3A, and 3B , a crimping monitoring system  30  may be configured to evaluate or monitor a crimping process. For example, and without limitation, crimping monitoring system  30  may include an electrical characteristic sensor  32  and/or a controller  34 . Sensor  32  may be connected (e.g., electrically) to terminal  10 ,  12  and/or conductor  20 . Sensor  32  may or may not be directly electrically connected to terminal  10 ,  12  and conductor  20  (see, e.g.,  FIG. 2 ). Sensor  32  may be connected with and/or include controller  34  and/or a display  50 . 
     With embodiments, sensor  32  may be configured to sense (e.g., measure, monitor, detect, etc.) an electrical characteristic of terminal  12  and/or conductor  20 , such as, for example, resistance, impedance, voltage, voltage drop, conductance, capacitance, current, and/or other electrical characteristics. In embodiments, sensor  32  may, for example, comprise a voltage drop sensor  32 A (e.g., a voltmeter, an ohmmeter, and/or an ammeter), one or more discrete probes, a sense resistor R sense , a voltage source/current source  36 , and/or a shunt resistor R shunt . Sensor  32  may be connected to and/or integrated with a crimping machine/device  38 , such as a press (e.g., hydraulic, pneumatic, etc.). 
     In embodiments, controller  34  may include one or more electronic controllers and/or electronic processors, such as a programmable microprocessor and/or microcontroller. In embodiments, controller  34  may include, for example, an application specific integrated circuit (ASIC). Controller  34  may include a central processing unit (CPU), memory, and/or an input/output (I/O) interface. Controller  34  may be configured to perform various functions, including those described in greater detail herein, with appropriate programming instructions and/or code embodied in software, hardware, and/or other medium. In embodiments, controller  34  may include a plurality of controllers and/or may be distributed among various portions of network. 
     With embodiments, such as generally illustrated in  FIGS. 2, 3A, 3B, 7, and 8 , controller  34  may be connected (e.g., electrically, wirelessly, via wired connection, etc.) to sensor  32 . Controller  34  may be configured to receive data, signals, and/or information from sensor  32  relating to one or more electrical characteristics of terminal  12  and/or conductor  20  sensed by sensor  32 . 
     In embodiments, sensor  32  may sense one or more electrical characteristics of terminal  12 , conductor  20 , and/or a crimping device  38  during a crimping operation. A crimping operation may include, for example, applying forces F to terminal  12 , such as via moving fixtures  40 ,  42  of a crimping device  38  closer together and/or into contact with each other, which may include electrically connecting fixtures  40 ,  42  with each other. Applying forces F may cause terminal  12  to clamp/crimp onto conductor  20 , which may include bending and/or deformation of terminal portions  14 ,  16 . First fixture  40  may include, for example, a punch. Second fixture  42  may include, for example, an anvil. Clamping/crimping terminal  12  with conductor  20  may restrict and/or prevent relative movement between terminal  12  and conductor  20 , and may provide and/or improve (e.g., reduce resistance of, reduce disconnection risk, etc.) an electrical connection between terminal  12  and conductor  20 . 
     In embodiments, such as generally illustrated in  FIG. 3B , sensor  32  may be connected to first fixture  40 . At least in an initial, non-crimping state, first fixture  40  may be connected to ground and/or electrically isolated from the rest of crimping device  38  (e.g., from second fixture  42 , an applicator  44 , and/or an actuator/ram  46 ). For example, and without limitation, crimping device  38  may include an electrical isolator (e.g., a plastic member) between first fixture  40  and applicator  44  and/or actuator  46 . First fixture  40  may be selectively connected to terminal  12  and/or conductor  20  (e.g., during crimping). At least in an initial, non-crimping state, second fixture  42  may be electrically isolated from ground and/or the rest of crimping device  38 , and may be electrically isolated from first fixture  40  when device  38  is not crimping. In such example configurations, sensor  32  may provide a current (e.g., via voltage/current source  36 ) to first fixture  40 , such as via shunt resistor R shunt . When first fixture  40  is not crimping (e.g., is out of contact with terminal  12  and/or conductor  20 ), the sensor current may flow to ground. When first fixture  40  is crimping, the sensor current may also flow through the terminal-conductor interface to a sense resistor R sense  of sensor  32 . In embodiments, such an example configuration could be reversed such that sensor  32  may provide current to second fixture  42 , and first fixture  40  may be electrically isolated from the rest of device  38  and from ground. 
     With embodiments, the one or more electrical characteristics that may be sensed by sensor  32  may correspond to, or be indicative of, the quality of the electrical connection between terminal  12  and conductor  20  before, during, and/or after crimping. For example, as generally illustrated in  FIGS. 4 and 5 , sensor  32  may be configured to sense a voltage drop across the connection/interface between terminal  12  and conductor  20 , and the voltage drop may correspond to the electrical resistance and/or quality of the connection. A lower/smaller voltage drop may, for instance, indicate a relatively high quality connection. Quality of the connection may correspond to physical aspects (e.g., strength) of the connection and/or electrical aspects of the connection. 
     As generally illustrated in  FIGS. 4, 5, 6, and 9 , crimping may include one or more phases/stages. For example, in a first phase, terminal  12  and conductor  20  may be placed in proximity and/or contact with each other without any compression/crimping force F being applied. In a first phase, a voltage drop and/or resistance sensed by sensor  32  may be relatively high. In a second phase, compression/crimping force F may be applied to form a crimped terminal  12 . The voltage drop and/or resistance sensed by sensor  32  may generally decrease as force F is applied. Force F may be applied, for example, until a generally stable value of the electrical characteristic is reached. In a third phase, force F may be reduced and/or removed, and the voltage drop and/or resistance sensed by sensor  32  may increase, at least slightly, as force F decreases. An increase in a voltage drop may correspond to, or be indicative of, an elasticity of terminal  12  and/or conductor  20 , which may comprise, in an embodiment, copper. For example, and without limitation, applying crimping force F to terminal  12  and/or conductor  20  may reduce a voltage drop to about 737 μV, and/or the removal/reduction of crimping force F may result in an increase of the voltage drop to about 772 μV (e.g., a change of about 35 μV or about 5%). 
     In embodiments, controller  34  may include and/or be connected to a display  50  and may be configured to cause display  50  to present visual representations or graphs of sensed electrical characteristics, such as the graphs shown in  FIGS. 4, 5, and 6 . In embodiments, controller  34  may be configured to determine if a crimped connection/interface is of sufficiently high quality. For example, and without limitation, controller  34  may analyze a voltage drop sensed during or after a second phase and/or third phase of crimping and compare that voltage drop to an expected voltage drop. If the sensed voltage drop is within a predetermined/specified range, controller  34  may determine that the connection is of sufficient quality. If the sensed voltage drop is outside of a predetermined/specified range, controller  34  may determine that the connection is not of a sufficient quality and/or that an error has occurred. Controller  34  may be configured to display a quality of the connection and/or an error message on display  50 . 
     In embodiments, such as generally illustrated in  FIGS. 7 and 8 , sensor  32  of crimping monitoring system  30  may connect with terminal  12  and/or conductor  20  via first fixture  40  (e.g., a punch) and/or second fixture  42  (e.g., an anvil). Applicator  44  may support at least one of first fixture  40  and second fixture  42 . First fixture  40  and/or second fixture  42  may or may not be connected (e.g., electrically) with an applicator  44  of crimping device  38 . Crimping device  38  may include an actuator  46  (e.g., a ram) that may be configured to actuate first fixture  40  (e.g., may move first fixture  40  toward second fixture  42  to cause crimping). System  30  may compensate for the resistance of first fixture  40 , second fixture  42 , applicator  44 , and/or actuator  46  when monitoring crimping. For example, and without limitation, sensor  32  and/or controller  34  may be configured to determine/obtain a resistance (or expected voltage drop) of first fixture  40 , second fixture  42 , applicator  44 , and/or actuator  46  such as prior to crimping and/or prior to connecting terminal  12  with conductor  20 . With embodiments, a resistance of applicator  44  may be about 0.4 Ohms, for example. If terminal  12  and conductor  20  are disposed in contact with fixtures  40 ,  42 , fixtures  40 ,  42  may be electrically connected in series with each other, terminal  12 , and conductor  20 , all of which may be electrically connected in parallel with applicator  44 . Sensor  32  and/or controller  34  may be configured to compensate for (e.g., remove/ignore the effects of) the resistance of fixture  40 , fixture  42 , and/or applicator  44  while monitoring crimping. In embodiments, a resistance of one or more components of system  30  may be preloaded/stored in sensor  32  and/or controller  34 . 
     In embodiments, such as generally illustrated in  FIG. 8 , applicator  44  may be electrically insulated from ground and/or from second fixture  42 . In such embodiments, an initial resistance (or voltage drop) may reflect, or be indicative of, an open circuit until terminal  12  and/or conductor  20  are disposed in contact with fixtures  40 ,  42 . If sensor  32  is connected to terminal  12  and/or conductor  20  via first fixture  40  and/or second fixture  42 , system  30  may be configured to monitor crimping (e.g., sense an electrical characteristic), even if one of terminal  12  and conductor  20  is not electrically conductive (e.g., a voltage drop/resistance across fixtures  40 ,  42  and the conductive one of terminal  12  and conductor  20  may change during crimping). One of terminal  12  and conductor  20  may not be conductive, for example, for insulation crimps and/or sealing crimps. 
     With embodiments, during a crimp cycle, actuation of first fixture  40  via actuator  46  may include sliding movement of first fixture  40  and/or actuator  46 , which may alter (e.g., increase) a resistance of crimping device  38 . As generally illustrated in  FIGS. 7 and 8 , crimping device  38  may include a connector  48  that may be configured to provide an electrical connection (e.g., a low resistance connection that may effectively act as a short) between applicator  44  and actuator  46  to reduce, minimize, and/or eliminate the effect of such a change in resistance. Connector  48  may include, for example, a braid strap. 
     In embodiments, crimping monitoring system  30  may include a crimping force sensor  60  (see, e.g.,  FIG. 2 ). Crimping force sensor  60  may be configured to monitor crimping force F before, during, and/or after crimping (e.g., during the first, second, and/or third phases). Crimping force sensor  60  may be connected to controller  34 . Crimping force sensor  60  may be configured for generating a force profile (see, e.g.,  FIG. 6 ) that may correspond to a crimp height and/or compaction of conductor  20 . Crimping force sensor  60  may be configured for generating the force profile via controller  34 . System  30  may be configured to (e.g., simultaneously) monitor one or more electrical characteristics of crimping device (e.g., voltage drop across a connection interface) and crimping forces F. 
     As generally illustrated in  FIG. 9 , in embodiments, a method of crimping and/or monitoring crimping may, in step  70 , include a sensor  32  sensing/obtaining one or more initial values of one or more electrical characteristics (e.g., a voltage drop) of system  30 . In step  72 , sensor  32  may be connected to at least one of terminal  12  and conductor  20 . In step  74 , sensor  32  may sense an initial value of an electrical characteristic (e.g., a voltage drop) of an interface of terminal  12  and conductor  20 . In step  76 , a crimping force F may be applied to terminal  12  and/or conductor  20 , and sensor  32  may sense the electrical characteristic of terminal  12  and/or conductor  20  while the crimping force F is being applied. In step  78 , sensing may include sensing a change (e.g., a decrease) in the electrical characteristic during a second phase of crimping (e.g., while crimping forces F are being applied). In step  80 , crimping may be ended, crimping forces F may be reduced, and/or crimping forces F may be removed. In step  82 , sensing may include sensing a second change (e.g., an increase) in the electrical characteristic during a third phase of crimping (e.g., as or after crimping forces F are removed). If the first change and/or second change is outside of a predetermined/specified range, controller  34  may determine that the connection is not of a sufficient quality and/or that an error has occurred. Additionally or alternatively, controller  34  may determine that the connection is not of a sufficient quality and/or that an error has occurred if a compression force sensor  60  indicates a compression force that is not within a specified/predetermined range. Controller  34  may be configured to control operation of crimping device  38  (e.g., movement of first fixture  40 , second fixture  42 , and/or applicator  44 ), such as according to information received from sensor  32 . 
     In embodiments, connecting sensor  32  to terminal  12  and conductor  20  may include indirectly connecting sensor  32  to terminal  12  and/or conductor  20 . For example, and without limitation, sensor  32  may be directly connected to fixture  40  and fixture  42 , which may be directly connected with terminal  12  and/or conductor  20 . At least one of terminal  12  and conductor  20  may not be electrically conductive. For example, and without limitation, if one of terminal  12  and conductor  20  is not electrically conductive, sensor  32  may be configured to monitor and/or determine a crimp quality according to an electrical characteristic of the conductive one of terminal  12  and conductor  20  via first fixture  40  and/or second fixture  42 . 
     With embodiments, voltage/current source  36  of sensor  32  may include voltage source  36 A and/or a current source  36 B. In embodiments, sensing an electrical characteristic may include providing a voltage and/or a current (e.g., via a voltage/current source  36 , a voltage source  36 A, and/or a current source  36 B) to one or more of terminal  12 , conductor  20 , fixture  40 , fixture  42 , and/or applicator  44 . A provided current may include, for example, and without limitation, include a substantially constant current of about 1 Ampere. 
     Although various features and functions of certain embodiments have been described herein in connection with terminal  12  for illustration, such embodiments are not limited to a certain type of terminal and could be used in connection with a wide range of elements, including, without limitation, terminal  10 . 
     With embodiments, a crimping monitoring system  30  may include a sensor  32  that may be configured for electrical connection with a first element  10 ,  12  and/or a second element  20 . System  30  may include a crimping device  38  that may include a first crimping fixture  40  and a second crimping fixture  42 . Crimping device  38  may be configured to crimp said first element  10 ,  12  and said second element  20  together. Sensor  32  may be configured to monitor an electrical characteristic of at least one of said first element  10 ,  12  and said second element  20  during crimping (e.g., via first fixture  40  and/or second fixture  42 ). The sensor may be configured for indirect electrical connection with at least one of first element  10 ,  12  and second element  20  via at least one of first crimping fixture  40  and second crimping fixture  42 . 
     Various embodiments are described herein for various apparatuses, systems, and/or methods. Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. It will be understood by those skilled in the art, however, that the embodiments may be practiced without such specific details. In other instances, well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. Those of ordinary skill in the art will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments. 
     Reference throughout the specification to “various embodiments,” “with embodiments,” “in embodiments,” or “an embodiment,” or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “with embodiments,” “in embodiments,” or “an embodiment,” or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined, in whole or in part, with the features, structures, or characteristics of one or more other embodiments without limitation given that such combination is not illogical or non-functional. 
     It should be understood that references to a single element are not necessarily so limited and may include one or more of such element. Any directional references (e.g., plus, minus, upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader&#39;s understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of embodiments. 
     Joinder references (e.g., attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily imply that two elements are directly connected/coupled and in fixed relation to each other. The use of “e.g.” throughout the specification is to be construed broadly and is used to provide non-limiting examples of embodiments of the disclosure, and the disclosure is not limited to such examples. Uses of “and” and “or” are to be construed broadly (e.g., to be treated as “and/or”). For example, and without limitation, uses of “and” do not necessarily require all elements or features listed, and uses of “or” are intended to be inclusive unless such a construction would be illogical. 
     It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the present disclosure. 
     Furthermore, the mixing and matching of features, elements and/or functions between various examples is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that features, elements, and/or functions of one example may be incorporated into another example as appropriate, unless described otherwise, above. Moreover, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the scope thereof. Therefore, it is intended that the present teachings not be limited to the particular examples illustrated by the drawings and described in the specification, but that the scope of the present disclosure will include any embodiments falling within the foregoing description and the appended drawings.