Method of crimp quality monitoring and system for use with a hydraulic crimping apparatus

Abstract

A method and system of monitoring the quality of a crimp of a crimp terminal in a hydraulic crimping apparatus. The method includes determining a pressure of hydraulic fluid supplied to a hydraulic crimp head of the hydraulic crimping apparatus, determining a flow rate of the hydraulic fluid supplied to the hydraulic crimp head of the hydraulic crimping apparatus, and analyzing the pressure and flow rate of the hydraulic fluid to determine whether the crimp is defective or not defective.

Description

Technical Field

[0001] This article generally covers crimping quality monitoring methods and systems for monitoring the crimping quality of hydraulic crimping equipment. Background Technology

[0002] Electrical terminals are typically crimped onto wires to form leads using crimping equipment. The crimping equipment has a crimping tool consisting of a first part and a second part. The first part is mounted to a base for supporting the electrical terminal, and the second part is mounted to a crimping head (ram) that can move toward and away from the base to perform the crimping. In operation, the terminal is placed on the first part of the crimping tool, and one end of the wire is inserted into the terminal's collar or sleeve. A crimping stroke moves the crimping head toward the base, thereby crimping the terminal onto the wire.

[0003] Systems have been developed to monitor the crimping quality of non-hydraulic crimping equipment. When a defective crimp is detected, the lead is discarded. Some known crimping quality monitoring systems measure crimping quality by measuring the crimp height. Typically, a poor crimped connection results from terminals not being crimped to the correct crimp height for a given terminal and lead combination. However, many poor crimped connections will still exhibit the “correct” crimp height. Therefore, systems that monitor crimping quality based on crimp height may allow defective leads from the crimping equipment to pass through the monitoring. Furthermore, variations in crimp height or other physical changes in the crimped terminals are not themselves the cause of a defective crimped connection, but may indicate another factor leading to a poor connection. These factors include using the wrong terminal or lead size, missing strands, brush short circuits, crimp insulation, abnormal terminal placement, incorrect lead type, incorrect insulation stripping, etc. Because such defective crimped connections often have the appearance of high-quality crimped connections, these defects are difficult to identify so that timely corrective action can be taken.

[0004] Other known crimp quality monitoring systems detect defective crimped terminals by analyzing the crimping force applied to the terminals during actual crimping operations. For example, such systems collect force and displacement data during the crimping stroke and compare this data with standardized data collected from known good crimps during a learning phase. This comparison is used to determine whether a particular crimp meets acceptable standards. However, crimp quality monitoring systems based on force distribution are not without problems. These systems are inaccurate when measuring certain types of defective crimps. For example, the system is prone to incorrectly identifying crimps with insulation within the sleeve as good crimps. The system is also prone to incorrectly identifying some good crimps as defective.

[0005] While many known systems are available for electric and pneumatic crimping equipment, these known systems are not adequate for measuring the crimping quality achieved by hydraulic crimping equipment.

[0006] There is still a need for a crimping quality monitoring system that can be used to accurately monitor the crimping quality of large terminals that require the use of hydraulic crimping equipment for proper crimping. There is also a need for a crimping quality monitoring system that can be used to identify specific defects in crimping achieved using hydraulic crimping equipment. Summary of the Invention

[0007] The embodiments relate to a method for monitoring the crimping quality of crimped terminals in a hydraulic crimping apparatus. The method includes: determining the pressure of hydraulic fluid supplied to a hydraulic crimping joint of the hydraulic crimping apparatus; determining the flow rate of the hydraulic fluid supplied to the hydraulic crimping joint of the hydraulic crimping apparatus; and analyzing the pressure and flow rate of the hydraulic fluid to determine whether the crimping is defective or not. Attached Figure Description

[0008] Figure 1 An illustrative hydraulic crimping device and hydraulic delivery system with crimping quality monitoring according to an illustrative embodiment are presented.

[0009] Figure 2 An illustrative terminal is shown, which is crimped to a wire using a hydraulic crimping device.

[0010] Figure 3 This is an enlarged view of the pressure sensor and flow sensor, which are set to be in-line with the hydraulic delivery system.

[0011] Figure 4 It shows the use Figure 1 The flowchart illustrates an exemplary method for monitoring crimping quality using a crimping quality monitoring system.

[0012] Figure 5 It is a graph illustrating the pressure-displacement curves associated with the crimping of terminals in a hydraulic crimping device.

[0013] Figure 6 A second illustrative embodiment of a device for monitoring the crimping quality of a hydraulic crimping machine is shown.

[0014] Figure 7 A third illustrative embodiment of a device for monitoring the crimping quality of a hydraulic crimping machine is shown.

[0015] Figure 8 A fourth illustrative embodiment of a device for monitoring the crimping quality of a hydraulic crimping machine is shown.

[0016] Figure 9 A fifth illustrative embodiment of a device for monitoring the crimping quality of a hydraulic crimping machine is shown.

[0017] Figure 10A sixth illustrative embodiment of a device for monitoring the crimping quality of a hydraulic crimping machine is shown. Detailed Implementation

[0018] The description of illustrative embodiments of the invention is intended to be read in conjunction with the accompanying drawings, which will be considered an integral part of the entire written description. In the description of embodiments of the invention disclosed herein, any references to orientation or direction are intended merely for convenience of description and are not intended to limit the scope of the invention in any way. Terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “upward,” “downward,” “top,” and “bottom,” and their derivatives (e.g., “horizontally,” “downward,” “upward,” etc.) should be interpreted as indicating an orientation as described subsequently or as shown in the drawings discussed. These relative terms are merely for convenience of description and do not require the device to be constructed or operated in a particular orientation unless explicitly indicated otherwise. Terms such as “attach,” “fix,” “connect,” “link,” “interconnect,” etc., refer to a relationship in which structures are directly or indirectly fixed or attached to each other, either directly or indirectly through an intermediate structure, and to a movable or rigid attachment or relationship, unless explicitly stated otherwise. Furthermore, the features and benefits of the invention are illustrated with reference to preferred embodiments. Therefore, the present invention should not be explicitly limited to these preferred embodiments, which illustrate some feasible non-limiting combinations of features that may exist alone or in other combinations of features, the scope of which is defined by the appended claims.

[0019] Figure 1 An exemplary crimping device 10 with a crimping quality monitoring system 12, formed according to an illustrative embodiment, is shown. The crimping device 10 has a hydraulic head 14 with an upper portion 16 and a lower portion 18. The lower portion 18 receives hydraulic fluid from a hydraulic delivery system 20 therein.

[0020] The first mold half 22 is housed in the upper portion 16 of the hydraulic head 14. The second mold half 24 is housed in the lower portion 18 of the hydraulic head 14. In the illustrated embodiment, the first mold half represents a fixed part of the crimping tool detachably attached to the upper portion 16. The second mold half represents a movable part of the crimping tool detachably attached to the lower portion 18.

[0021] Figure 2A typical terminal 30 crimped onto a wire 32 is shown. Many different types and sizes of terminals 30 and wires 32 can be used with the crimping device 10. The crimping tool is used to terminate the terminal 30 onto the wire 32. For example, the second die half 24 is hydraulically driven initially toward and eventually away from the first die half 22 during the compression stroke. During the initial portion of the crimping stroke, the first die half 22 and the second die half 24 engage the terminal 30 and crimp the terminal 30 onto the wire 32.

[0022] like Figure 1 and 3 As best shown, the hydraulic system 20 includes a hydraulic pump 34, which is fluidly connected to the hydraulic head 14 via a hose 36 or other type of conduit. The hose 36 may be divided into two or more components 36a, 36b to allow various measuring devices to be positioned collinear with the flow of hydraulic fluid from the hydraulic pump 34 to the hydraulic head 14.

[0023] In the illustrated embodiment, hose 36a extends between hydraulic pump 34 and coupling member 38. Coupling member 38 is attached to pressure transducer 40. In various embodiments, hose 36a may have an internal diameter larger than the internal diameter of pressure transducer 40. Therefore, coupling member 38 may have a transition portion that reduces the internal diameter of coupling member 38 to allow proper mating of coupling member 38 with hose 36a and pressure transducer 40.

[0024] Flow meter 44 extends from pressure transducer 40. Flow sensor 46 extends from flow meter 44. In the illustrated embodiment shown, flow sensor 46 is rotatably coupled to flow meter 44 via rotary coupling 48. Coupling member 50 extends between flow meter 44 and hose 36b and secures flow meter 44 to hose 36b. Hoose 36b extends between flow meter 44 and hydraulic head 14.

[0025] The hydraulic delivery system 20 includes a hydraulic control 51. In the illustrated embodiment, the hydraulic control 51 includes a button used by the operator to reset the system, initiate the flow of hydraulic fluid, and discharge defective terminals. However, other types of hydraulic controls may be used, including but not limited to foot pedals.

[0026] The pressure converter 40 and flow sensor 46 transmit information to the controller or microprocessor 52. A wired or wireless connection can be provided between the pressure converter 40 and the controller 52. Similarly, a wired or wireless connection can be provided between the flow sensor 46 and the controller 52.

[0027] The pressure transducer 40 is a type that converts pressure into an analog electrical signal, such as, but not limited to, a strain gauge-based transducer. The conversion of pressure into an electrical signal is achieved through the physical deformation of a strain gauge, which is bonded to the diaphragm of the pressure transducer and wired in a Wheatstone bridge configuration. Therefore, pressure applied to the pressure transducer causes deflection of the diaphragm, which introduces strain into the strain gauge. This strain produces a change in resistance proportional to the pressure. Because the hydraulic system 20 is a closed system and the hydraulic fluid is incompressible, the pressure within the hose 36 is proportional to the pressure applied to the second die half 18 of the hydraulic head 14 and to the force applied to the crimped terminal 30 and the wire 32. Therefore, the signal transmitted from the pressure transducer 40 to the controller 52 represents the force applied to the terminal 30 during crimping.

[0028] Flow meter 44 is positioned or arranged to measure the flow rate of hydraulic fluid through hose 36. The flow meter measures the volumetric velocity of the hydraulic fluid through hose 36. Since hydraulic system 20 is a closed system and the hydraulic fluid is incompressible, the volume of fluid through hose 36 is proportional to the amount of fluid entering or leaving hydraulic head 14. Because the dimensions of the hydraulic receiving chamber 54 of hydraulic head 14, which receives hydraulic fluid from hydraulic delivery system 20, are known, any change in fluid volume is proportional to a change in displacement of the second mold half 24. Therefore, the flow rate of hydraulic fluid through hose 36 during crimping is proportional to the amount of displacement of the second mold half 24 and the amount of displacement of terminal 30. Flow sensor 46 stores the flow rate detected by flow meter 44 and transmits this information to controller 52.

[0029] In the illustrated embodiment, the pressure transducer 40, flow meter 44, and flow sensor 46 are shown collinear between the hydraulic pump 34 and the hydraulic head 14. However, in other illustrative embodiments, one or more of the pressure transducer 40, flow meter 44, and flow sensor 46 may be located in other locations, such as, but not limited to, within the hydraulic pump 34. Furthermore, the pressure transducer 40, flow meter 44, and flow sensor 46 may be discrete devices or may be integrated into one or more devices.

[0030] The quality of the crimping can be monitored by monitoring signals from the flow sensor 46 and the pressure transducer 40. For example, the crimping height of the crimped terminal 30 can be determined by analyzing the signal from the flow sensor 46. Alternatively, the change in crimping height from a baseline can be determined for the crimped terminal 30. Furthermore, other characteristics of the crimping can be analyzed by analyzing signals from the pressure transducer 40. For example, characteristics related to the force applied to the terminal 30 can be analyzed. Force data can be collected and used to determine the crimping quality. For example, force distribution can be generated and analyzed to analyze parameters such as the peak force applied to the terminal 30 and the amount of work performed to complete the crimping.

[0031] The controller or microprocessor 52 may have internal memory or a database for storing data, or alternatively, an external database or memory may be provided. The controller 52 collects information from the pressure converter 40 and the flow sensor 46. This information includes... Figure 5 The information shown in Figure 60 is plotted on a graph. Controller 52 analyzes the plotted information and compares it with the first preferred or target crimping force envelope 62 and the second preferred or target crimping force envelope 64. If the plotted information 60 is inside the region between the first preferred or target crimping force envelope 62 and the second preferred or target crimping force envelope 64, controller 52 provides visual output 66 to the operator indicating that the terminal is properly crimped to the wire. If the plotted information 60 is outside the region between the first preferred crimping force envelope 62 and the second preferred crimping force envelope 64, controller 52 provides visual output 68 to the operator indicating that the terminal is not properly crimped to the wire. The operator can remove the improperly crimped terminal from the article of manufacture. This visual output may include one or more of the following: an indication that the terminal is properly crimped; an indication that the terminal is not properly crimped; or an indication that the terminal may be properly crimped, but requires visual inspection by the operator.

[0032] The controller 52 can be used to drive various components of the crimping device 10, such as an injector (not shown), which discards leads with poorly crimped terminals. The controller 52 can be used to drive the hydraulic delivery system 20 through the crimping stroke. As part of a control scheme or based on operator input and / or input from the pressure converter 40 or the flow sensor 46, the controller 52 can automatically drive the components.

[0033] The crimping quality monitoring system 12 generally includes a controller 52, a pressure converter 40, and a flow sensor 46. In alternative embodiments, the crimping quality monitoring system 12 may also include other components. Optionally, the controller 52 may be part of a computer. The controller 52 may have a microprocessor for processing signals from the pressure converter 40 and the flow sensor 46. The crimping quality monitoring system 12 uses the controller 52 to analyze and / or manipulate data from the pressure converter 40 and the flow sensor 46 to monitor crimping quality.

[0034] The signals appearing on the pressure transducer 40 (indicating the force applied to the terminal 30) and the signals appearing on the flow sensor 46 (indicating the relative position of the mating halves of the hydraulic head 14) are monitored and recorded by the controller 52. The signals can be recorded as pairs of data elements, one pair for each discrete time increment during the crimping cycle. Thus, each force element is associated with a specific time component and a specific position component of the hydraulic head 14.

[0035] In an exemplary embodiment, such as Figure 4 As shown, during the crimping stroke, pressure 80, proportional to the crimping force, is measured by pressure transducer 40. During the crimping stroke, flow rate 82, proportional to the displacement of the die, is measured by flow meter 44 and flow sensor 46.

[0036] Pressure and flow rate can be measured continuously or at predetermined intervals based on time or the position of the crimping tool. For example, a predetermined sampling time can be selected, and pressure and flow rate can be measured at each discrete sampling time. Alternatively or additionally, pressure and flow rate can be measured when the crimping tool is at a predetermined crimping height position. The position of the crimping tool can be detected by a distance sensor (not shown).

[0037] Optionally, controller 52 can be used to create a force distribution based on the measured pressure. Controller 52 can use the force distribution to monitor crimp quality. For example, as previously described, the force distribution can be analyzed to determine if a particular crimp is defective.

[0038] exist Figure 6 A second illustrative embodiment of a crimping quality monitoring system 112 in a hydraulic delivery system 120 is shown. The crimping quality monitoring system 112 provides a simple simulation method for measuring the amount of hydraulic fluid that has been pumped through the hydraulic delivery system 120. The crimping quality monitoring system 112 includes one or more pipes 141 to measure or meter the amount of force in the hydraulic lines and the amount of fluid displacement required to move the crimping tool.

[0039] Each tube 141 has a plunger 142 movably positioned inside the tube 141. The plunger 142 can move or slide along the length of the tube 141. The movement of the plunger 142 is proportional to the amount of fluid entering one end 143 of the tube 141. The area inside the tube 141 through which the hydraulic fluid must pass to reach the face of the plunger 142 is constant. Therefore, assuming a set initial position for the plunger 142, the volume of fluid entering the tube 141 can be calculated by monitoring and measuring the movement of the plunger 142 within the tube 141 by multiplying the area inside the tube by the length of the plunger's movement. A displacement sensor 144 can be used to monitor the displacement of the plunger 142. Since the hydraulic system 120 is a closed system and the hydraulic fluid is incompressible, the volume of fluid entering one end 143 of the tube 141 and causing displacement of the plunger 142 is proportional to the amount of fluid entering or leaving the hydraulic head. Therefore, any movement of the plunger 142 is proportional to the change in displacement of the second die half of the crimping tool.

[0040] A pressure monitor 140, which converts pressure into an analog electrical signal, is also provided on pipe 141, such as, but not limited to, a strain gauge-based transducer. The conversion of pressure into an electrical signal is achieved through the physical deformation of a strain gauge, which is bonded to the diaphragm of the pressure transducer and connected in a Wheatstone bridge configuration. Therefore, pressure applied to the pressure transducer causes deflection of the diaphragm, which introduces strain into the strain gauge. This strain produces a change in resistance proportional to the pressure. Since the hydraulic system 120 is a closed system and the hydraulic fluid is incompressible, the pressure in pipe 141 is proportional to the pressure applied to the hydraulic head and to the force applied to the crimped terminals and wires. Therefore, the signal transmitted from the pressure monitor 40 during crimping indicates the force applied to the terminals.

[0041] Displacement sensor 144 and pressure monitor 140 transmit information to controller or microprocessor 152. A wired or wireless connection can be provided between pressure monitor 140 and controller 152. Similarly, a wired or wireless connection can be provided between displacement sensor 144 and controller 152.

[0042] In this embodiment, a system for venting air from pipe 141 can be provided. If air is introduced into system 120, it may remain in the system without a means of releasing it, thereby hindering or preventing the operation of plunger 142. To allow air to be removed from system 120, the system for venting air from pipe 141 includes a set of protocols to vent the line when necessary. The system applies pressure to valve 149 in pipe 141 parallel to the side of pipe 141, which, together with the proper orientation of the attached hose, causes air to accumulate in a defined area 150. As the pressure continues to increase, valve 149 is opened, forcing the air out of the system.

[0043] exist Figure 7 A third illustrative embodiment of the crimping quality monitoring system 212 in the hydraulic delivery system 220 is shown. In this embodiment, three cylinders 241 and pistons 242 are coupled together and have hydraulic fluid traveling through them. Electromagnetically controlled high-pressure valves (not shown) are provided to control the movement of hydraulic fluid into and out of each cylinder 241. A crankshaft 245 connects all pistons 242 together. The pistons 242 are offset from each other by 120 degrees to maintain a constant power output. The hydraulic delivery system 220 uses a two-stroke design with only intake and exhaust.

[0044] When piston 242 is offset by 120 degrees, there is some overlap, but for ease of explanation and understanding, only one operation of piston 242 will be provided. Initially, the solenoid control valve opens to allow fluid to enter cylinder 241. When fluid begins to fill cylinder 241, piston 242 is at its highest position, similar to the position during the intake stroke of an engine. The pressure in cylinder 241 is used to move crankshaft 245, which is connected to the other pistons, thus performing the process in all three cylinders but at different times. Once piston 242 reaches its lowest point, the valve allowing fluid in closes, and the valve allowing fluid out opens. When this occurs, the power of another piston 242 is applied, and the fluid pushes piston 242 downwards, which forces piston 242 in cylinder 241 to move upwards, displacing fluid out of cylinder 241 and towards the crimping tool. To convert piston motion into volumetric flow rate, meter 244 is needed to count the number of crankshaft rotations. The number of rotations is multiplied by the volume of each cylinder to provide the volume of fluid displaced. Similar to other designs, a high-pressure monitor 240 is provided after the volumetric flow meter 244 to measure or quantify the pressure of the fluid being delivered to the crimping tool.

[0045] exist Figure 8 The diagram illustrates a fourth illustrative embodiment of a crimping quality monitoring system 312 in a hydraulic delivery system 320. A conduit 341 has a fan 342 positioned transversely to the flow of the hydraulic fluid. A volumetric flow meter 344 records the number of rotations of the fan 342, thereby allowing the amount of fluid that has passed through the system 320 to be counted. Similar to other designs, a high-pressure monitor 340 is provided after the volumetric flow meter 344 to measure or quantify the pressure of the fluid delivered to the crimping tool.

[0046] exist Figure 9The diagram illustrates a fifth illustrative embodiment of a crimping quality monitoring system 412 in a hydraulic delivery system 420. In this embodiment, the hydraulic fluid is ferromagnetic or has magnetic additives. A flow meter 444 controls the amount of fluid passing through a specific cross-section of a conduit 441. A conductor 442 is wound around the conduit 441, beneath which the fluid passes. Because the fluid is magnetic, the movement of the fluid will generate a moving B-field (flux), which will result in an electric current in the conductor 442. The current is measured and converted into volumetric displacement. In various embodiments, voltage spikes associated with the flow rate of the magnetic fluid can be measured and recorded, allowing a second means of measuring the amount of fluid that has passed through the system. Similar to other designs, a high-pressure monitor 440 will be provided after the volumetric flow meter 444 to measure or meter the pressure of the fluid being delivered to the crimping tool.

[0047] exist Figure 10 The diagram illustrates a sixth illustrative embodiment of a crimping quality monitoring system 512 in a hydraulic delivery system 520. In this embodiment, a sensor 544 is located on or monitors a button 542 used by the operator to allow hydraulic fluid to flow to the crimping tool. The sensor 544 monitors the duration of button 542 engagement, thereby allowing calculation of the amount of fluid flowing to the crimping tool. Similar to other designs, a high-pressure monitor 540 is provided to measure or meter the pressure of the fluid delivered to the crimping tool. By monitoring pressure and time, the controller can determine whether the crimping is good or bad.

[0048] In a seventh illustrative embodiment of the crimping quality monitoring system, the quality of the crimp can be measured using time. In this embodiment, the time required for the hydraulic head to move from a first position to a second position is timed. The measured time is compared to an established target time range, which represents the time required for proper crimping to occur. If the measured time falls within the target time range, a visual output is provided to the operator indicating that the terminal is properly crimped to the wire. If the measured time is outside the target time, a visual output is provided to the operator indicating that the terminal is not properly crimped to the wire. In one illustrative embodiment, time measurement may begin when a target low pressure is reached in the hydraulic system and may end when a target high pressure is reached in the hydraulic system. In another illustrative embodiment, time measurement may begin when a target initial flow rate is reached in the hydraulic system and may end when a target final flow rate is reached in the hydraulic system.

[0049] The eighth illustrative embodiment of the crimping quality monitoring system monitors fluid flow rate by counting the number of strokes of a piston located in a hydraulic pump. A piston is provided to allow fluid to leave the hydraulic pump and be pumped or displaced toward the crimping tool. To convert piston motion into volumetric flow rate, a meter is provided to count the number of piston cycles. The number of cycles is multiplied by the cylinder volume to provide the volume of fluid displaced. Similar to other designs, a high-pressure monitor is provided to measure or meter the pressure of the fluid delivered to the crimping tool. Alternatively, a pressure monitor can be used to calculate the number of cycles, thus eliminating the need for a counting meter. As the piston cycles, pulses of hydraulic fluid pressure occur. Therefore, the pressure monitor can also be used to count the number of pressure peaks in the hydraulic system, which are related to the number of piston cycles.

[0050] Various embodiments of methods for monitoring the crimping quality of crimped terminals in a hydraulic crimping apparatus may include measuring: a) the pressure of hydraulic fluid supplied to the hydraulic crimping joint of the hydraulic crimping apparatus in a hydraulic system; or b) the flow rate of hydraulic fluid supplied to the hydraulic crimping joint of the hydraulic crimping apparatus in a hydraulic system; or c) the time required to move the hydraulic crimping joint from a first position to a second position; or any combination of a), b), or c). The method may also include analyzing the measured pressure, flow rate, time, or any combination thereof for a given pressure, flow rate, or time to determine whether the crimping is defective or not.

[0051] Although the invention has been described with reference to preferred embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from the spirit and scope of the invention as defined by the appended claims. In particular, those skilled in the art will appreciate that the invention can be implemented in other specific forms, structures, arrangements, proportions, dimensions, and with other elements, materials, and components without departing from the spirit or essential characteristics of the invention. Those skilled in the art will understand that the invention can be used with many modifications to its structure, arrangement, proportion, dimensions, materials, and components, and can be used in other ways in the practice of the invention, particularly suited to specific environments and operational requirements, without departing from the principles of the invention. Therefore, the embodiments disclosed herein are to be considered illustrative rather than restrictive in all respects, and the scope of the invention is defined by the appended claims, and not limited to the foregoing description or embodiments.

Claims

1. A method of monitoring the quality of a crimp of a crimped terminal (30) in a hydraulic crimping apparatus (10), the method comprising: measuring a) the pressure of hydraulic fluid supplied to a hydraulic crimp head (14) of the hydraulic crimping apparatus (10) in a hydraulic system (20), and b) the flow rate of hydraulic fluid supplied to the hydraulic crimp head (14) of the hydraulic crimping apparatus (10) in the hydraulic system (20), sending the pressure and the flow rate to a controller or microprocessor (52); analyzing the measured pressure and flow rate for the corresponding pressure, flow rate to determine if the crimp is defective or not defective.

2. The method of claim 1, further comprising supplying the hydraulic fluid to the hydraulic crimping apparatus (10) from a hydraulic pump (34) that is connected to the hydraulic crimping apparatus (10) by a closed system.

3. The method of claim 1, wherein the pressure of the hydraulic fluid supplied to the hydraulic crimp head (14) of the hydraulic crimping apparatus (10) is proportional to the force applied to a terminal (30) being crimped by the hydraulic crimp head (14) of the hydraulic crimping apparatus (10).

4. The method of claim 1, wherein the flow rate of the hydraulic fluid supplied to the hydraulic crimp head (14) of the hydraulic crimping apparatus (10) is proportional to the displacement of a terminal (30) being crimped by the hydraulic crimp head (14) of the hydraulic crimping apparatus (10).

5. A system (12) for monitoring the quality of a crimp of a hydraulic crimping apparatus (10), the system (12) comprising: a hydraulic pump (34) connected to a crimping tool; a pressure sensor disposed between the hydraulic pump (34) and the crimping tool, the pressure sensor monitoring the pressure of hydraulic fluid in the system (12); a flow sensor (46) disposed between the hydraulic pump (34) and the crimping tool, the flow sensor (46) monitoring the flow of hydraulic fluid in the system (12); a controller (52) analyzing the pressure of hydraulic fluid provided by the pressure sensor and the flow of hydraulic fluid provided by the flow sensor (46) to determine if the crimp is defective.

6. The system (12) of claim 5, wherein the pressure of hydraulic fluid in the system (12) monitored by the pressure sensor is proportional to the pressure applied to a die half (24) of a crimping tool of the crimping apparatus (10).

7. The system (12) of claim 5, wherein the flow of hydraulic fluid in the system (12) monitored by the flow sensor (46) is proportional to the displacement of a die half (24) of a crimping tool of the crimping apparatus (10).

8. The system (12) of claim 5, wherein the pressure sensor is a pressure transducer (40) that converts the pressure of hydraulic fluid in the system (12) to an analog electrical signal.

9. The system (12) of claim 5, wherein the flow sensor (46) comprises a flow meter (44) that measures a volumetric flow rate of hydraulic fluid in the system (12).

10. The system (12) of claim 5, wherein the flow sensor (46) comprises a movable device disposed in the system (12) that moves as a function of a change in flow rate of hydraulic fluid in the system (12).

11. The system (12) of claim 5, wherein the hydraulic fluid has magnetic properties and the flow sensor (46) measures a moving flux field generated by movement of the hydraulic fluid.

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