System and method for a hydraulic tool

Abstract

A hydraulic power tool includes a trigger, a motor, a pump, a hydraulic circuit, a fluid reservoir, a pressure sensor, and a controller. When the trigger is depressed, the controller initiates motor operation, causing the pump to move hydraulic fluid through the circuit. The controller monitors pressure via the sensor, calculates a pressure derivative representative of a rate at which the pressure varies over time, and increments a buffer counter when the pressure derivative is zero or near zero. When the pressure derivative remains zero or near zero for a predetermined period of time, which indicates completion of a work operation, the controller automatically releases hydraulic fluid from the circuit back to the reservoir.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 708,130, filed October 16, 2024, the entire contents of which are incorporated herein by reference. Background Technology

[0003] Operating tools (e.g., cutting tools, crimping tools, etc.) allow operators to perform various operations (e.g., crimping, cutting, etc.) on many different workpieces (e.g., wires, power cables, sheet metal, etc.). For example, some cutting tools may include a cutting head that is driven (e.g., hydraulically or electrically) into the workpiece (e.g., cable) to cut through it. Summary of the Invention

[0004] According to one aspect of this disclosure, a hydraulic power tool may include a trigger; a motor; a pump driven by the motor; a hydraulic circuit in fluid communication with the pump; a fluid reservoir in communication with the hydraulic circuit to store hydraulic fluid; a pressure sensor in communication with the hydraulic circuit; and a controller in communication with the motor, the pressure sensor, and the trigger. The controller can initiate motor operation in response to the pressing of the trigger, wherein the motor operation causes the pump to move hydraulic fluid from the fluid reservoir through the hydraulic circuit. The controller can monitor the pressure within the hydraulic circuit via pressure measurements from the pressure sensor. The controller can calculate a pressure derivative, which represents the rate of change of pressure over time. When the pressure derivative is zero or close to zero, the controller can increment a buffer counter. The controller can detect when the pressure derivative remains zero or close to zero for a predetermined time period to indicate that the operation is complete. When the pressure derivative is detected to be zero or close to zero for a predetermined time period, the controller can automatically release the hydraulic fluid from the hydraulic circuit back to the fluid reservoir.

[0005] In some examples, the controller can further determine when the pressure drops below a threshold, where the threshold can be a rate threshold, which indicates the rate at which the pressure measurement changes over time.

[0006] In some examples, the rate threshold can indicate that the hydraulic power tool has completed the cut.

[0007] In some examples, the rate threshold can indicate that the piston in the hydraulic circuit has reached the closed position.

[0008] In some examples, the controller may be further configured to monitor the pressure derivative within the hydraulic circuit and determine when the pressure derivative remains at or near zero for a predetermined period of time before automatically releasing the hydraulic fluid.

[0009] In some examples, the predetermined time period can range from about 50 milliseconds to about 250 milliseconds.

[0010] In some examples, the controller may be further configured to detect when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of a work operation, and subsequently detect when the pressure drops below a second threshold indicating the completion of the work operation.

[0011] In some examples, the second threshold may have a pressure value lower than the first threshold.

[0012] In some examples, the hydraulic power tool may further include at least one of the following: recording and storing the maximum pressure sensed during a work operation, wherein the work operation can be defined as starting when the trigger is pressed and ending when the pressure exceeds the second threshold; or recording and storing the maximum pressure sensed during a work cycle, wherein the work cycle can be defined as starting when the trigger is pressed and ending when the trigger is released.

[0013] In some examples, the controller may include a buffer counter that increments when the pressure derivative is zero or close to zero and decrements when the pressure derivative is not close to zero.

[0014] In some examples, the controller can automatically release the hydraulic fluid when the buffer counter reaches a predetermined full state.

[0015] According to another aspect of the invention, a method of operating a hydraulic power tool may include: activating motor operation in the hydraulic power tool in response to activation of an actuator of the hydraulic power tool; activating a pump of the hydraulic power tool via the activation of the motor operation to move hydraulic fluid from a fluid reservoir through a hydraulic circuit; monitoring pressure in the hydraulic circuit via a pressure sensor disposed within the hydraulic power tool; calculating a pressure derivative, the pressure derivative representing the rate of change of pressure over time; incrementing a buffer counter when the pressure derivative is zero or close to zero; detecting when the pressure derivative remains zero or close to zero for a predetermined time period, indicating that the operation of the hydraulic tool has been completed; and releasing the hydraulic fluid from the hydraulic circuit back to the fluid reservoir when the pressure derivative is detected to remain zero or close to zero for the predetermined time period.

[0016] In some examples, the predetermined time period can range from about 50 milliseconds to about 250 milliseconds.

[0017] In some examples, the method may further include detecting when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of the operation before monitoring the pressure derivative.

[0018] In some examples, the method may further include detecting when the pressure in the hydraulic circuit drops below a second threshold indicating the initial completion of the operation before calculating the pressure derivative.

[0019] In some examples, the method may further include generating a status flag in the firmware when a predetermined pressure condition is detected during the operation.

[0020] According to another aspect of this disclosure, a method of operating a hydraulic power tool may include: initiating motor operation in the hydraulic power tool in response to activation of an actuator; pumping hydraulic fluid from a fluid reservoir through a hydraulic circuit via the initiation of the motor operation; monitoring pressure within the hydraulic circuit; detecting when the rate of change of the pressure exceeds a first threshold indicating completion of an operation of the hydraulic tool; and releasing the hydraulic fluid from the hydraulic circuit back to the fluid reservoir when the rate of change of the pressure exceeds the first threshold indicating completion of the operation.

[0021] In some examples, the first threshold may correspond to the rate of pressure drop.

[0022] In some examples, the first threshold may correspond to the rate of pressure rise.

[0023] In some examples, the method may further include generating a status flag in the firmware when the rate of change of the pressure is detected to exceed the first threshold. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the specification, serve to explain the principles of these embodiments:

[0025] Figure 1 A side view of an example hydraulic tool according to aspects of this disclosure.

[0026] Figure 2 For use Figure 1 A cross-sectional view of an example cutting component of a hydraulic tool.

[0027] Figure 3 for Figure 1 A schematic diagram of the components of the hydraulic and electronic control system of a hydraulic tool.

[0028] Figure 4A for Figure 1 A flowchart illustrating an example cutting process using hydraulic tools.

[0029] Figure 4B For corresponding Figure 4A The graph shows the process.

[0030] Figure 5A for Figure 1 Another example of a hydraulic tool is a flowchart of a cutting process.

[0031] Figure 5B For corresponding Figure 5A The graph shows the process.

[0032] Figure 6A for Figure 1 Another example of a hydraulic tool cutting process flowchart.

[0033] Figure 6B For corresponding Figure 6A The graph shows the process.

[0034] Figure 7 The image above (A) is Figure 1 Another example of a cutting process using hydraulic tools is shown in the flowchart. Figure 7 The following diagram (B) corresponds to Figure 7 The above figure (A) is a graph of the process shown. Detailed Implementation

[0035] The foregoing discussion is provided to enable those skilled in the art to make and use embodiments of the invention. Given the advantages of this disclosure, various modifications to the illustrated embodiments will be apparent to those skilled in the art, and the principles herein can be applied to other embodiments and applications without departing from the embodiments of the invention. Therefore, embodiments of the invention are not intended to be limited to those shown, but are accorded the widest scope consistent with the principles and features disclosed herein.

[0036] Refer to the accompanying drawings for the following detailed description, in which similar elements in the different drawings have similar reference numerals. The drawings, not necessarily drawn to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Those skilled in the art will recognize that the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.

[0037] Before explaining any embodiments of the invention in detail, it should be understood that the invention is not limited in its application to the details of the construction and arrangement of the components set forth in the following description or illustrated in the following drawings. The invention can have other embodiments and can be practiced or performed in various ways. Furthermore, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered limiting. The use of “comprising,” “including,” or “having,” and variations thereof herein is intended to cover the items listed thereafter and their equivalents and additional items. Unless otherwise specified or limited, the terms “installation,” “connection,” “support,” and “linkage,” and variations thereof are used extensively and cover direct and indirect installation, connection, support, and linkage. Furthermore, “connection” and “linkage” are not limited to physical or mechanical connections or linkages.

[0038] In some examples, the hydraulic tool may include an automatic blade retraction mechanism that automatically retracts the blades of the hydraulic tool (e.g., returns them to their "original" position). For example, the automatic blade retraction mechanism can retract the blades after the hydraulic tool has completed a cut (or crimp, or other operation) to relieve force or pressure on the tool, which can improve the overall reliability of the tool. For example, in use, the hydraulic tool may be configured to monitor the operation on the workpiece, and once the cut is complete, the blade retraction mechanism can automatically release hydraulic fluid from the hydraulic chamber back to a reservoir (e.g., fluid holding position). In some examples, during the operation, the hydraulic tool may record the maximum cutting pressure (e.g., the maximum pressure required to cut the workpiece) and the maximum circulating pressure (e.g., the maximum pressure reached during the operation).

[0039] refer to Figure 1The image illustrates an example of a hydraulic tool 100 according to the present disclosure. In one example, the hydraulic tool 100 may be a cutting tool. The hydraulic tool 100 includes a housing 102 that receives a cutter assembly 104 having a head 106 and a body 108. In one example, the body 108 of the assembly 104 may be positioned within the housing 102 of the tool 100, while the head 106 of the assembly 104 is positioned outside the housing 102. The housing 102 may further include a handle 110 to allow a user to grip and manipulate the tool 100. In one example, the handle 110 extends substantially perpendicular to the head 106. However, in other examples, the handle 110 may extend substantially parallel to the head 106 (e.g., in a straight line with the head 106). In some examples, a user can enable or disable operation of the tool 100 via the activation of an actuator. In some examples, the actuator may be in the form of a trigger 112 positioned on the handle 110. However, in other examples, tool 100 can be controlled using a remote device or a mobile application (e.g., on a mobile phone or laptop), but other configurations are also possible.

[0040] In some examples, to control the operation of tool 100, the user activates tool 100 by pressing trigger 112. Correspondingly, tool 100 is deactivated by releasing trigger 112. In one particular example, tool 100 includes a battery socket 114 configured to receive and hold a battery (e.g., a rechargeable lithium-ion battery) to power tool 100 (e.g., ...). Figure 3 The example shown is battery 156. However, in other examples, tool 100 may include a power cord to power tool 100.

[0041] In some examples, the header 106 of component 104 typically defines a U-shaped form, but header 106 can define other geometric shapes, such as C-shapes or other shapes. For example, Figure 2 Example descriptions can be used with Figure 1 Another example of a cutter assembly 120 used in conjunction with a hydraulic tool 100.

[0042] like Figure 2As shown, the head 106 of the cutter assembly 120 includes a first frame 122 and a second frame 124. The second frame 124 is movable relative to the first frame 122 such that the tool head 106 can be opened to insert a workpiece into the cutting zone 126. In some examples, the tool head 106 can be moved to a closed position to facilitate cutting the workpiece in the cutting zone 126. The tool head 106 further includes a first blade and a second blade located within the respective first and second frames 122, 124. For example, the tool head 106 includes a first blade 128 slidably disposed in the first frame 122 and a second blade 130 coupled to the second frame 124. The first blade 128 is movable from the proximal end of the cutting zone 126 toward the second blade 130 at the distal end of the cutting zone 126. Thus, the first blade 128 and the second blade 130 provide a guillotine-like cutting action. However, in other examples, the first and second blades 128, 130 can be arranged to provide other cutting actions (e.g., shearing action, scissor action, etc.).

[0043] In some examples, the hydraulic actuator assembly is coupled to the proximal end 132 of the head 106 and configured to move the first blade 128 toward the second blade 130 to cut an object (e.g., a workpiece) positioned in the cutting zone 126. For example, the actuator assembly includes a pump configured to supply pressurized hydraulic fluid to a hydraulic circuit and a pressure head configured to move the first blade 128. In some examples, the pump supplies pressurized hydraulic fluid that causes the pressure head to move to provide a corresponding movement toward the first blade 128 toward the second blade 130 through the cutting zone 126.

[0044] Turn now Figure 3 The diagram shows a hydraulic and electronic control system 140 of a hydraulic tool 100. The hydraulic and electronic control system 140 may include one or more user interaction components 142, a controller 144, a memory 146, a fluid reservoir 148 in fluid communication with a hydraulic circuit 150 and a pump 152, a pressure sensor 154, a battery 156, a motor 158, and a gear reducer 160.

[0045] In some examples, user interaction components 142 (one or more) are configured to provide input to the hydraulic power tool 100, such as to the controller 144 of the hydraulic power tool 100. Specifically, in this example, user interaction component 142 includes a trigger 112 (e.g., see...). Figure 1 ), control panel, one or more switches, one or more buttons, one or more interactive indicator lights, soft touch screen or panel, other similar switches, or any combination thereof.

[0046] Controller 144 (which may also be referred to as a motor control unit or motor inverter) includes a processor and is connected to memory 146, user interaction component 142(one or more), hydraulic circuit 150, pump 152, and pressure sensor 154, and is powered by battery 156. For example, hydraulic circuit 150, pump 152, or pressure sensor 154 is configured to provide certain operational information and operational data to controller 144, as further described below. Additionally, in some examples, controller 144 may include a printed circuit board assembly (PCBA). In some examples, memory 146 is a non-transitory computer-readable medium and includes a program storage area and a data storage area. Specifically, the data storage area contains multiple value lookup tables. For example, at least one stored lookup table may contain workpiece information or data, such as the maximum fluid pressure in hydraulic circuit 150, as further described below. The program storage area and data storage area may contain combinations of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, hard disk, SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The program storage area contains instructions that, when executed by the processor, enable the controller 144 to operate the tool 100.

[0047] In some examples, the electric motor 158 is powered by the battery 156 and controlled by the controller 144. Furthermore, the electric motor 158 is configured to drive the pump 152 via a gear reducer 160. Specifically, the pump 152 is driven to draw fluid from the fluid reservoir 148 (e.g., typically stored at or near atmospheric pressure) to pressurize the fluid and deliver it to the hydraulic circuit 150. For example, when a user presses trigger 112 to perform a work operation (e.g., a cutting operation) with tool 100, the pump 152 is driven to provide pressurized hydraulic fluid to the hydraulic circuit 150. The pressurized hydraulic fluid within the hydraulic circuit then drives the pressure head of the hydraulic actuator cylinder within the hydraulic circuit 150 toward the head 106, causing the first vane 128 to move from its nearest side position (e.g., as...). Figure 2 The original position (as illustrated in the example) moves through the cutting zone 126 toward the farthest position (e.g., the closed position) adjacent to the second blade 130.

[0048] Additionally, in some examples, during operation, the controller 144 monitors the pressure of the hydraulic fluid within the hydraulic circuit 150 via a pressure sensor 154. That is, the pressure sensor 154 (e.g., a pressure transducer) is in communication with a fluid distribution network, such as located within the hydraulic circuit 150. Specifically, the pressure sensor 154 is configured to provide the controller 144 with a measurement indicating the pressure within the hydraulic circuit 150.

[0049] Typically, when the operation is complete, the user releases trigger 112, which causes controller 144 to stop motor 158. When motor 158 stops, tool 100 pauses the pressure head and maintains the hydraulic pressure at the current level. In some examples, to release high-pressure fluid from hydraulic circuit 150 back to fluid reservoir 148, tool 100 may include a second trigger, which can be actuated by the user to initiate a hydraulic drain procedure. Alternatively, in other examples, the user can continue to drive motor 158 until a deadhead or "bottoming out" occurs, which automatically triggers the hydraulic drain procedure but may cause unnecessary wear on the tool. In some examples, the hydraulic drain procedure includes opening one or more valves within hydraulic circuit 150 (e.g., in response to a command from controller 144) to allow pressurized fluid to be released back (e.g., back to) fluid reservoir 148. Thus, in some examples, the hydraulic drain procedure is configured as an electronically controlled program by controller 144.

[0050] exist Figure 2 In the example operation of the cutter assembly 120 shown, the cutting head 106 includes a first blade 128 and a second blade 130. The cutting head 106 completes its operation when the first blade 128 and the second blade 130 are in a closed position after the workpiece has been cut. More generally, the closed position can be the position where the blades 128 and 130 of the head 106 are at their minimum distance from each other. For simplicity, the following discussion will refer to the cutter assembly 120, the first blade 128, and the second blade 130.

[0051] According to some examples, the hydraulic tool 100 is configured to automatically determine when a work operation (e.g., a cutting operation, a crimping operation, etc.) is completed, and based on such determination, to retract the first blade 128 to its original position. More specifically, based on such determination, the hydraulic tool 100 releases high-pressure fluid from the hydraulic circuit 150 back to the fluid reservoir 148 to allow the first blade 128 to retract to its original position, as described above. For example, the controller 144 determines the state of the work operation based on pressure signals from the pressure sensor 154, and controls the automatic blade retraction based on these pressure signals.

[0052] Figure 4A-7The examples illustrate flowcharts and graphical representations of an example process using pressure sensor readings as feedback during operation. Typically, one or more stages of these processes are integrated into a low-level firmware algorithm embedded within the controller 144. The firmware can be a Basic Input / Output System (BIOS), an Extensible Firmware Interface (EFI), or other types of firmware. In some examples, advanced firmware algorithms may be used. Specifically, the advanced firmware algorithm is configured to be deployed within a flash memory chip and allows for updates. In further examples, the algorithm may be implemented within a subsystem. These subsystems are configured as semi-standalone devices, which are part of a larger system.

[0053] More specifically, Figure 4A The example illustrates an example process 170 that uses measured pressure values ​​and predetermined thresholds to initiate automatic blade retraction, with the corresponding graph 172 (see, for example, [link to graph]). Figure 4B This example illustrates pressure measurements that change over time during the execution of process 170. Figure 4A As shown, in stage 174, the user activates the tool via actuation of an actuator (e.g., pressing trigger 112). In some examples, actuator activation involves detecting that trigger 112 has been pulled, which is sensed by controller 144, and starting motor 158 in stage 174 (e.g., see T1 on graph 172). After motor 158 is started, motor 158 drives pump 152 to pressurize hydraulic circuit 150, causing hydraulic fluid to flow from reservoir 148 through circuit 150 to initiate movement of first blade 128 toward second blade 130.

[0054] During operation of motor 158, controller 144 continuously monitors whether the pressure in hydraulic circuit 150 has exceeded a first threshold 176, which indicates that the cutting operation has begun in stage 178 (e.g., see T2 on graph 172). In this way, the first threshold 176 serves as a "cutting start threshold" to distinguish between initial system pressurization and higher pressures generated when the first blade 128 encounters resistance from the workpiece positioned in cutting zone 126. Specifically, controller 144 receives pressure measurements from pressure sensor 154 at regular intervals and compares these measurements with the first threshold 176, which is stored as a predetermined value in memory 146 based on tool operating characteristics and workpiece properties. In stage 178, controller 144 is configured to generate a flag in firmware to indicate that the cutting threshold 176 has been exceeded, thereby providing a status indication for subsequent process stages.

[0055] During the cutting operation, at stage 180, controller 144 continuously monitors the pressure of hydraulic circuit 150 and checks whether the pressure has dropped below a second threshold 182 (e.g., see T3 on graph 172). In some examples, a pressure drop below the second threshold 182 indicates that the workpiece has been cut because the resistance exerted by the workpiece is released when it is cut. In this way, the second threshold 182 acts as a "cutting end threshold" and is set as a pressure value below a first threshold 176. As described above regarding the first threshold 176, controller 144 continuously receives pressure measurements from pressure sensor 154 and compares these values ​​with the second threshold 182 stored in memory 146. When controller 144 determines that the cutting end threshold 182 has been exceeded, controller 144 may generate a flag in firmware indicating that the cutting end threshold has been exceeded to indicate this state change.

[0056] After controller 144 determines that the workpiece has been cut, process 170 proceeds to stage 184, where controller 144 continuously monitors the pressure derivative (e.g., configured to ramp rate) to determine if the derivative is zero or close to zero. Pressure derivative monitoring in stage 184 serves as an additional verification step to ensure that the cutting operation has been completed. For example, if the pressure derivative is not close to zero, this indicates that the hydraulic circuit 150 is still experiencing pressure changes and pressure may continue to build up (e.g., during continued cutting). In some examples, when the pressure derivative is close to zero, this indicates that there is no pressure buildup in the system because the workpiece no longer exerts a reaction force on the blades (one or more).

[0057] In some examples, a buffer counter (e.g., a timer) can be implemented to verify that the cutting process has been completed before initiating the discharge procedure. This is particularly important for cutting operations involving workpieces such as stranded cables, in which the pressure derivative may temporarily drop to zero when the blades 128, 130 initially cut one strand of the cable, but cutting resumes once the other strand of the cable is contacted. This monitoring further prevents premature determination of cutting completion if partial cutting has already occurred or if the workpiece material properties result in complex pressure response patterns during the cutting process. The calculation of the pressure derivative may involve comparing continuous pressure measurements over time to determine the rate of pressure change within the hydraulic circuit 150.

[0058] Once the pressure derivative is zero or close to zero (e.g., indicating the workpiece has been cut), the firmware increments the buffer counter, and process 170 proceeds to stage 186. In stage 186, controller 144 determines if the buffer is full (e.g., the timer has expired), which corresponds to verifying that the pressure derivative remains zero or close to zero for a preset time period. This time-based verification ensures that pressure stability is continuous rather than temporary, further verifying that the cutting operation has been fully completed and the hydraulic circuit 150 has reached a stable operating state. In this example, the preset time period is configured to range from approximately 50 milliseconds to approximately 250 milliseconds, but other time intervals can be selected based on tool characteristics, workpiece type, and operational requirements. When the pressure derivative exceeds the zero range (e.g., greater than or less than zero), indicating that tool 100 is causing pressure build-up or drop, the firmware can decrement the buffer counter to address pressure instability. In some implementations, when a pressure change is detected, the buffer can be reset to zero, or the firmware can decrement the buffer at a rate higher than the rate at which it increments, for example, decrementing by two milliseconds for every millisecond outside the zero pressure derivative range, and incrementing by only one millisecond for every millisecond within the zero range. If the controller 144 determines that the pressure derivative has not remained zero for a preset amount of time, process 170 loops back to stage 184, in which the controller 144 continuously monitors the pressure derivative.

[0059] Once the pressure derivative or ramp rate remains zero for a preset time period, the controller 144 determines in stage 188 that the cutting is complete. This completion determination initiates a hydraulic release procedure, which returns pressurized hydraulic fluid to the reservoir 148 and retracts the first blade 128 to its "original" position. Furthermore, in stage 188, the controller 144 clears the buffer counter and resets the status flag in the firmware. Therefore, in stage 188, an operation reset is performed, indicating that the tool 100 is ready for another operation.

[0060] The pressure relief in process 170 allows tool 100 to avoid being unloaded or "bottoming out" after the workpiece has been cut, which can lead to excessive pressure buildup and premature wear of system components. For example, performing process 170 and initiating the relief procedure after buffer verification can mitigate pressure jumps in hydraulic circuit 150 (illustrated in section 190 of graph 172). By mitigating the risks of these pressure spikes and associated mechanical stresses, process 170 can further increase the service life of tool 100 while improving operational reliability and stability.

[0061] Figure 5A and 5BExample 192 illustrates another example process 192 using pressure derivatives to initiate automatic blade retraction, where the corresponding graph 194 illustrates the pressure measurements changing over time during process 192. Figure 5A As shown, process 192 begins at stage 196, which includes activating the actuator. In this example, activating the actuator includes pulling trigger 112, which initiates the starting of motor 158 and subsequently increases the pressure in hydraulic circuit 150. At stage 202, the first blade 128 cuts through the workpiece, which causes the pressure in hydraulic circuit 150 to drop, as... Figure 5B As indicated by arrow 200 in graph 194. In stage 206, controller 144 continuously monitors the pressure in loop 150 and determines when the rate of pressure drop exceeds a predetermined rate threshold 204, which indicates that the cutting operation is complete. Based on this determination, in stage 208, motor 158 stops and the hydraulic release procedure is initiated. In some examples, the hydraulic release procedure is initiated automatically without requiring the user to release trigger 112. Process 192 then proceeds to stage 210, where an operation reset is performed, indicating that tool 100 is ready for another job operation.

[0062] The pressure relief in process 192 allows tool 100 to avoid being unloaded after the workpiece has been cut. For example, performing process 192 after the workpiece has been cut can prevent pressure jumps in hydraulic circuit 150 (illustrated in part 212 of graph 194), which can extend the service life of tool 100 and improve operational reliability.

[0063] Figure 6A and 6B The example illustrates another example process 214 using the pressure derivative to initiate automatic blade retraction, with the corresponding graph 216 illustrating the pressure measurements changing over time during process 214. Figure 6AAs shown, process 214 begins at stage 218, where the actuator is activated. In this example, activating the actuator involves pulling trigger 112, which starts motor 158 and causes pressure to rise in hydraulic circuit 150. Process 214 proceeds to stage 220, where the first blade 128 cuts through the workpiece, causing pressure to drop in circuit 150. Once the piston or pressure head in hydraulic circuit 150 reaches the end of its stroke, pressure rises in circuit 150 at stage 222. Process 214 then proceeds to stage 226, where controller 144 monitors the pressure in circuit 150 and detects when the pressure rises at a sufficiently fast rate exceeding a predetermined rate threshold 224, indicating that tool 100 has reached a deadhead state and initiating a release procedure. This deadhead state occurs when the hydraulic system encounters maximum resistance, which may be due to the completion of the cutting operation or the actuation of tool 100 without the workpiece being positioned in blades 128, 130. In stage 228, motor 158 stops and trigger 112 is released. Process 214 then proceeds to stage 230, where an operation reset is performed, indicating that tool 100 is ready for another job operation.

[0064] The pressure relief in process 214 allows tool 100 to avoid being unloaded after the workpiece has been cut. For example, after the workpiece has been cut and the first blade 128 has reached the closed position and can no longer move distally, process 214 prevents pressure jumps in the hydraulic circuit 150 (illustrated in part 232 of graph 216). This, in turn, protects the system components of tool 100 and extends the life of tool 100.

[0065] Figure 7 The upper (A) and lower (B) figures illustrate another example of process 234 using pressure thresholds during operation, with the corresponding graph 236 illustrating the pressure measurements over time during process 234. Figure 7As shown in Figure (A) above, process 234 begins at stage 238, where the actuator is activated. In this example, activating the actuator involves pulling trigger 112, which starts motor 158 and begins to increase the pressure in circuit 150. At stage 242, the pressure in hydraulic circuit 150 exceeds a first threshold 240, which indicates that a cutting operation has begun. At stage 244, the first blade 128 cuts through the material of the workpiece, causing the pressure in circuit 150 to drop. At stage 246, the actuator is deactivated. In this example, deactivating the actuator involves releasing trigger 112. After trigger 112 is released, process 234 then proceeds to stage 248, where a hydraulic release operation is initiated, and an operation reset is performed, indicating that tool 100 is ready for another job operation.

[0066] according to Figure 7 In process 234 of the above figure (A), if the user does not release trigger 112 (e.g., stage 246 does not occur), tool 100 may continue to run to an unloaded state, as shown by the large pressure change at the end of curve 236 at section 250. This highlights the importance of user intervention in process 234, where manually releasing trigger 112 serves as the primary mechanism for initiating the venting procedure and preventing excessive pressure buildup and potential system damage after the cut is complete.

[0067] Figure 4A-7 Examples of implementations of algorithms employing a linear event sequence are provided. The algorithm restarts after completion. However, in other implementations, one or more of these algorithms can be modified to include while loops, for loops, or other firmware elements that allow the process to continue running until all stopping conditions are met. Additionally, in some implementations, different related measurements are performed sequentially. However, in further implementations, measurements can be performed simultaneously or in different orders.

[0068] In light of the foregoing, according to some examples, after the hydraulic tool 100 completes a cut or crimp, the hydraulic tool 100 utilizes pressure measurements and thresholds to initiate automatic blade retraction by automatically releasing fluid from its hydraulic circuit 150 back to its fluid reservoir 148, thereby relieving the force or pressure on the tool 100. Therefore, one advantage of this feature is that it prevents the tool 100 from reaching maximum force or quality pressure after each cut, potentially contributing to improved reliability of the tool 100. In some examples, each of the aforementioned thresholds may be a single threshold stored in memory 146. In other examples, each threshold may include multiple thresholds in a lookup table stored in memory 146, and the controller 144 may retrieve the appropriate threshold from the lookup table based on specific operating variables (such as cut / crimp type, workpiece material type, etc.).

[0069] Additionally, in some examples, monitoring pressure during operation of the hydraulic tool 100 can provide an extra advantage. For example, during operation, the controller 144 can store in memory 146 the maximum cutting / crimping pressure (e.g., the maximum pressure required to cut / crimp the workpiece) and the maximum cycle pressure (e.g., the maximum pressure reached during operation).

[0070] For example, typically, when a user cuts material and then continues to extend the indenter in hydraulic circuit 150 until it reaches no-load, tool 100 can record the maximum circulating pressure or mass pressure sensed before trigger 112 is released. However, this maximum pressure may not be the pressure required for tool 100 to cut the material. For example, refer to the reference. Figure 4B The maximum circulating pressure 252 is shown in graph 172. This maximum circulating pressure 252 is reached after the workpiece has been cut. On the other hand, in Figure 4B The maximum cutting / crimping pressure 254 is also shown, which indicates the maximum pressure sensed during operation, which is less than the maximum cyclic pressure 252.

[0071] Since these two pressures are typically different (with the maximum cycle pressure 252 typically being greater than the maximum cutting pressure 254), the controller 144 can store both pressures 252 and 254 in memory 146. In some examples, these pressures 252 and 254 can be stored in a lookup table in memory 146. Such data can be beneficial for both engineering and service. For example, the data can be used to determine the type of cable being cut, helping to optimize threshold settings. As another example, the data can help set better daily cycles for life testing of tool 100.

[0072] Therefore, during operation, when the pressure measurement indicates that cutting is complete, the controller 144 can store the maximum pressure of the cycle prior to that moment (e.g., from the time the trigger 112 is pressed to the time the corresponding threshold is reached) as the maximum cutting pressure 254 in the memory 146. For example, this might occur... Figure 4A Stage 184 Figure 5A Phase 206, and Figure 6A Phase 226. When the entire loop is complete, for example in Figure 4A Stage 188, in Figure 5A Phase 210, in Figure 6A Phase 230, or Figure 7 In stage 248 of the above figure (A), the controller 144 can store the maximum pressure of the entire cycle (e.g., from the time when the trigger 112 is pressed to the time when the trigger 112 is released) as the maximum cycle pressure 252 in the memory 146.

[0073] In some embodiments, methods embodying aspects of the invention may be used to utilize, manufacture, or install the apparatus or system disclosed herein. Correspondingly, any description herein of a particular feature, capability, or intended purpose of an apparatus or system is generally intended to include disclosure of: methods of using such an apparatus to achieve the intended purpose; methods of otherwise achieving such capability; methods of manufacturing related components (or the entire apparatus or system) of such an apparatus or system; and methods of installing the disclosed (or otherwise known) components to support such purpose or capability. Similarly, unless otherwise indicated or limited, the discussion herein of any method of manufacture or use for a particular apparatus or system (including methods of installing said apparatus or system) is intended to essentially include disclosure of the features employed in such an apparatus or system and the capabilities achieved therein (as embodiments of the invention).

[0074] Further examples

[0075] Example 1. A hydraulic power tool includes: a trigger; a motor; a pump driven by the motor; a hydraulic circuit in fluid communication with the pump; a fluid reservoir in communication with the hydraulic circuit to store hydraulic fluid; a pressure sensor in communication with the hydraulic circuit; and a controller in communication with the motor, the pressure sensor, and the trigger, the controller being configured to: initiate motor operation in response to pressing the trigger, the motor operation causing the pump to move hydraulic fluid from the fluid reservoir through the hydraulic circuit; monitor the pressure in the hydraulic circuit via a pressure measurement from the pressure sensor; calculate a pressure derivative, the pressure derivative representing the rate of change of pressure over time; increment a buffer counter when the pressure derivative is zero or close to zero; detect when the pressure derivative remains zero or close to zero for a predetermined time period to indicate that the operation is complete; and automatically release the hydraulic fluid from the hydraulic circuit back to the fluid reservoir when the pressure derivative is detected to be zero or close to zero for the predetermined time period.

[0076] Example 2. A hydraulic power tool according to Example 1, wherein the controller further determines when the pressure drops below a threshold, wherein the threshold is a rate threshold, the rate threshold indicating the rate at which the pressure measurement changes over time.

[0077] Example 3. A hydraulic power tool according to Example 2, wherein the rate threshold indicates that the hydraulic power tool has completed a cut.

[0078] Example 4. A hydraulic power tool according to Example 2, wherein the rate threshold indicates that the piston of the hydraulic circuit has reached a closed position.

[0079] Example 5. A hydraulic power tool according to Example 1, wherein the controller is further configured to monitor the pressure derivative in the hydraulic circuit and determine when the pressure derivative remains at or near zero for a predetermined period of time before automatically releasing the hydraulic fluid.

[0080] Example 6. A hydraulic power tool according to Example 5, wherein the predetermined time period is in the range of about 50 milliseconds to about 250 milliseconds.

[0081] Example 7. A hydraulic power tool according to Example 1, wherein the controller is further configured to detect when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of a work operation, and subsequently detect when the pressure drops below a second threshold indicating the completion of the work operation.

[0082] Example 8. A hydraulic power tool according to Example 7, wherein the second threshold has a pressure value lower than the first threshold.

[0083] Example 9. A hydraulic power tool according to Example 7 or Example 8, further comprising at least one of the following: recording and storing a maximum pressure sensed during a work operation, the work operation being defined as starting when the trigger is pressed and ending when the pressure exceeds the second threshold; or recording and storing a maximum pressure sensed during a work cycle, the work cycle being defined as starting when the trigger is pressed and ending when the trigger is released.

[0084] Example 10. A hydraulic power tool according to Example 1, wherein the controller includes a damper counter that increments when the pressure derivative is zero or close to zero and decrements when the pressure derivative is not close to zero.

[0085] Example 11. A hydraulic power tool according to Example 10, wherein the controller automatically releases the hydraulic fluid when the buffer counter reaches a predetermined full state.

[0086] Example 12. A method of operating a hydraulic power tool, the method comprising: initiating motor operation in the hydraulic power tool in response to activation of an actuator of the hydraulic power tool; activating a pump of the hydraulic power tool via the activation of the motor operation to move hydraulic fluid from a fluid reservoir through a hydraulic circuit; monitoring pressure in the hydraulic circuit via a pressure sensor disposed within the hydraulic power tool; calculating a pressure derivative, the pressure derivative representing the rate of change of pressure over time; incrementing a buffer counter when the pressure derivative is zero or close to zero; detecting when the pressure derivative remains zero or close to zero for a predetermined time period, indicating that an operation of the hydraulic tool has been completed; and releasing the hydraulic fluid from the hydraulic circuit back to the fluid reservoir when the pressure derivative is detected to remain zero or close to zero for the predetermined time period.

[0087] Example 13. The method according to Example 12, wherein the predetermined time period is in the range of about 50 milliseconds to about 250 milliseconds.

[0088] Example 14. The method according to Example 12 or Example 13 further includes detecting when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of the operation before monitoring the pressure derivative.

[0089] Example 15. The method according to Example 14 further includes detecting when the pressure in the hydraulic circuit drops below a second threshold indicating the preliminary completion of the operation before calculating the pressure derivative.

[0090] Example 16. The method according to any one of Examples 12 to 15 further includes generating a status flag in the firmware when a predetermined pressure condition is detected during the operation.

[0091] Example 17. A method of operating a hydraulic power tool, the method comprising: initiating motor operation in the hydraulic power tool in response to activation of an actuator; pumping hydraulic fluid from a fluid reservoir through a hydraulic circuit via the initiation of the motor operation; monitoring pressure within the hydraulic circuit; detecting when the rate of change of the pressure exceeds a first threshold indicating completion of an operation of the hydraulic tool; and releasing the hydraulic fluid from the hydraulic circuit back to the fluid reservoir when the rate of change of the pressure exceeds the first threshold indicating completion of the operation.

[0092] Example 18. The method according to Example 17, wherein the first threshold corresponds to the rate of pressure drop.

[0093] Example 19. The method according to Example 17, wherein the first threshold corresponds to the rate of pressure rise.

[0094] Example 20. The method according to any one of Examples 17 to 19 further includes generating a status flag in the firmware when the rate of change of the pressure is detected to exceed the first threshold.

[0095] Furthermore, as used herein, unless otherwise limited or defined, "or" signifies a non-exclusive list of components or operations that can exist in any kind of combination, rather than an exclusive list of components that can only exist as substitutes for each other. For example, a list of "A, B, or C" represents the following options: A; B; C; A and B; A and C; B and C; and A, B, and C. Correspondingly, as used herein, the term "or" is intended to signify an exclusive alternative only when preceded by an exclusive term (e.g., "any one," "one of," "only one of," or "exact one of"). For example, a list of "one of A, B, or C" represents the following options: A, but not B and C; B, but not A and C; and C, but not A and B. A list beginning with "one or more" (and its variations) and containing "or" to separate the listed elements represents an option of one or more of any or all of the listed elements. For example, the phrases "one or more of A, B, or C" and "at least one of A, B, or C" represent the following options: one or more A's; one or more B's; one or more C's; one or more A's and one or more B's; one or more B's and one or more C's; one or more A's and one or more C's; and one or more A's, one or more B's, and one or more C's. Similarly, a list beginning with "multiple" (and its variations) and containing "or" to separate the listed elements represents an option for multiple instances of any or all of the listed elements. For example, the phrases "multiple A's, B, or C" and "two or more of A, B, or C" represent the following options: A and B; B and C; A and C; and A, B, and C.

[0096] As used herein, unless otherwise defined or limited, directional terms are used for ease of reference in the discussion of a particular figure or example. For example, reference to a downward direction (or other direction) or a top position (or other position) may be used to discuss multiple aspects of a particular example or figure, but it is not necessarily required that similar orientations or geometries be present in all installations or configurations.

[0097] Furthermore, as used herein, unless otherwise limited or defined, “generally parallel” means a direction within ±12 degrees (e.g., within ±6 degrees) of the reference direction, including end values.

[0098] Furthermore, as used herein, unless otherwise limited or defined, “generally perpendicular” means a direction within ±12 degrees (e.g., within ±6 degrees) perpendicular to the reference direction, including end values.

[0099] Furthermore, as used herein, unless otherwise limited or defined, "integral" and its derivatives (e.g., "integrally") describe an element that is manufactured as a single part without fasteners, adhesives, etc., to hold the separate components together. For example, an element formed from a single sheet of metal or stamped, cast, or otherwise molded using a single die to hold separately formed parts together is an integral (and integrally formed) element. Conversely, an element formed from multiple parts initially formed separately and subsequently joined together is not an integral (or integrally formed) element.

[0100] Additionally, unless otherwise stated or limited, the terms “about” and “approximately” as used herein relative to a reference value mean a deviation from the reference value of ±15% or less, including the endpoints of the range. Similarly, the terms “substantially equal” (and similar expressions) as used herein relative to a reference value mean a deviation from the reference value of less than ±10%, including the endpoints. Where explicitly specified, “substantially” may specifically indicate a deviation from the reference value in a numerical direction. For example, “substantially less” a reference value (and similar expressions) means a value that is 10% or more less than the reference value, while “substantially greater than” a reference value (and similar expressions) means a value that is 10% or more more than the reference value.

[0101] Furthermore, as used herein, unless otherwise limited or specified, “substantially identical” means two or more parts or systems manufactured or used according to the same processes and specifications, wherein the differences between said parts or systems are within acceptable tolerances of the relevant processes and specifications. For example, two parts may be considered substantially identical if they are manufactured according to the same standardized manufacturing steps using the same materials within the same acceptable dimensional tolerance range (e.g., specified for a particular process or product).

[0102] Unless otherwise expressly stated, ordinal numbers are used herein for ease of reference, and their use is generally based on the order in which particular components are presented in the relevant sections of this disclosure. For example, at this point, names such as “first,” “second,” etc., generally only indicate the order in which such labeled components are introduced into the discussion, and generally do not indicate or require a particular spatial, functional, temporal, or structural primacy or order.

[0103] The foregoing description of the disclosed embodiments is intended to enable any person skilled in the art to make or use the invention. Given the advantages of this disclosure, various modifications to these embodiments will be apparent to those skilled in the art, and the principles defined herein can be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not limited to the embodiments shown herein, but is accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydraulic power tool, comprising: trigger; motor; A pump driven by the motor; A hydraulic circuit in fluid communication with the pump; A fluid reservoir connected to the hydraulic circuit to store hydraulic fluid; A pressure sensor connected to the hydraulic circuit; as well as A controller that communicates with the motor, the pressure sensor, and the trigger, the controller being configured to: In response to the pressing of the trigger, the motor operation is initiated, and the motor operation causes the pump to move hydraulic fluid from the fluid reservoir through the hydraulic circuit; The pressure within the hydraulic circuit is monitored using pressure measurements from the pressure sensor. Calculate the pressure derivative, which represents the rate of change of pressure over time; When the pressure derivative is zero or close to zero, the buffer counter is incremented. The operation is considered complete when the pressure derivative remains at or near zero for a predetermined period of time. and When the pressure derivative is detected to be zero or close to zero within a predetermined time period, the hydraulic fluid is automatically released from the hydraulic circuit back to the fluid reservoir.

2. The hydraulic power tool of claim 1, wherein, The controller further determines when the pressure drops below a threshold, wherein the threshold is a rate threshold, which indicates the rate at which the pressure measurement changes over time.

3. The hydraulic power tool of claim 2, wherein, The rate threshold indicates that the hydraulic power tool has completed the cut.

4. The hydraulic power tool of claim 2, wherein, The rate threshold indicates that the piston in the hydraulic circuit has reached the closed position.

5. The hydraulic power tool of claim 1, wherein, The controller is further configured to monitor the pressure derivative within the hydraulic circuit and determine when the pressure derivative remains at or near zero for a predetermined period of time before automatically releasing the hydraulic fluid.

6. The hydraulic power tool of claim 5, wherein, The predetermined time period is in the range of approximately 50 milliseconds to approximately 250 milliseconds.

7. The hydraulic power tool according to claim 1, wherein, The controller is further configured to detect when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of a work operation, and subsequently detect when the pressure drops below a second threshold indicating the completion of the work operation.

8. The hydraulic power tool according to claim 7, wherein, The second threshold has a pressure value lower than the first threshold.

9. The hydraulic power tool according to claim 7, further comprising at least one of the following: Record and store the maximum pressure sensed during a job operation, defined as starting when the trigger is pressed and ending when the pressure exceeds the second threshold; or The maximum pressure sensed during a work cycle is recorded and stored, the work cycle being defined as starting when the trigger is pressed and ending when the trigger is released.

10. The hydraulic power tool according to claim 1, wherein, The controller includes a buffer counter that increments when the pressure derivative is zero or close to zero and decrements when the pressure derivative is not close to zero.

11. The hydraulic power tool according to claim 10, wherein, When the buffer counter reaches a predetermined full state, the controller automatically releases the hydraulic fluid.

12. A method for operating a hydraulic power tool, the method comprising: In response to the activation of the actuator of the hydraulic power tool, the motor in the hydraulic power tool is started to operate; The pump of the hydraulic power tool is activated by the start-up of the motor, so that hydraulic fluid moves from the fluid reservoir through the hydraulic circuit; The pressure in the hydraulic circuit is monitored via a pressure sensor disposed within the hydraulic power tool; Calculate the pressure derivative, which represents the rate of change of pressure over time; When the pressure derivative is zero or close to zero, the buffer counter is incremented. The detection of when the pressure derivative remains at or near zero within a predetermined time period indicates that the operation of the hydraulic tool is complete; as well as When the pressure derivative is detected to remain at or near zero for a predetermined time period, the hydraulic fluid is released from the hydraulic circuit back to the fluid reservoir.

13. The method according to claim 12, wherein, The predetermined time period is in the range of approximately 50 milliseconds to approximately 250 milliseconds.

14. The method of claim 12, further comprising detecting when the pressure in the hydraulic circuit exceeds a first threshold indicating the start of the operation before monitoring the pressure derivative.

15. The method of claim 14, further comprising detecting when the pressure in the hydraulic circuit drops below a second threshold indicating the preliminary completion of the operation before calculating the pressure derivative.

16. The method of claim 12, further comprising generating a status flag in the firmware when a predetermined pressure condition is detected during the operation.

17. A method for operating a hydraulic power tool, the method comprising: In response to the activation of the actuator, the motor operation in the hydraulic power tool is initiated; The hydraulic fluid is pumped from the fluid reservoir through the hydraulic circuit via the start-up of the motor. Monitor the pressure within the hydraulic circuit; Detect when the rate of change of the pressure exceeds a first threshold indicating the completion of the operation of the hydraulic tool; as well as When the rate of change of the pressure is detected to exceed a first threshold indicating the completion of the operation, the hydraulic fluid is released from the hydraulic circuit back to the fluid reservoir.

18. The method according to claim 17, wherein, The first threshold corresponds to the rate of pressure drop.

19. The method of claim 17, wherein, The first threshold corresponds to the rate of pressure rise.

20. The method of claim 17, further comprising generating a status flag in the firmware when the rate of change of the pressure is detected to exceed the first threshold.

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