Closed-loop power control for blow molds

Abstract

A blowing tool is provided. The blowing tool includes a blowing tool housing, a motor for driving a fan, disposed within the blowing tool housing, and a controller disposed within the blowing tool housing and electrically connected to the motor to control a power output of the motor. The controller is configured to perform a plurality of operations. The plurality of operations includes receiving a power setpoint, receiving a measured power, comparing the power setpoint and the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting the power output of the motor based on the control signal.

Description

Field of InterestThe present disclosure relates generally to exterior power tools, such as blow tools.BackgroundExterior tools such as blow tools are commonly used to concentrate debris such as leaves by a blow function. To achieve the desired effect, various nozzles or attachments may be attached to the blow mold. However, the nozzles or attachments may impair the performance of the blow molding tool.Accordingly, improved blow tools are desired in the art. In particular, blowing tools which ensure constant performance over all attachments would be advantageous.Brief DescriptionAspects and advantages of the invention according to the present disclosure will be set forth in part in the description which follows, or may be obvious from the description, or may be learned by practice of the technique.In accordance with one embodiment, a blow mold is provided. The blow mold includes a blow mold housing, a motor for driving a blower disposed in the blow mold housing, and a controller disposed in the blow mold housing and electrically connected to the motor to control the power output of the motor. The control device is configured to carry out a plurality of activities. The plurality of operations includes receiving a power setpoint, receiving a measured power, comparing the power setpoint and the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting the power output of the motor based on the control signal.In accordance with another embodiment, a method of controlling a motor of a blow mold is provided. The method includes receiving a power setpoint, receiving a measured power, comparing the power setpoint and the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting a power output of the motor based on the control signal.These and other features, aspects and advantages of the present invention will become more fully understood by reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the technique and together with the description serve to explain the principles of the technique.Brief Description of the DrawingsA full and further disclosure of the present invention, including the best mode of making and using the present systems and methods directed to one skilled in the art, is set forth in the specification, which references the appended figures. FIG. 1A is a perspective view of a blow mold in accordance with embodiments of the present disclosure; FIG. 1B is a side view of the blow mold of FIG. 1A in accordance with embodiments of the present disclosure; FIG. 2 is a cross-sectional view of a portion of the blow mold of FIGS. 1A through 1B in accordance with embodiments of the present disclosure; FIG. 3A is a perspective view of a flat nozzle attachment for the blow mold of FIGS. 1A through 1B in accordance with embodiments of the present disclosure; FIG. 3B is a perspective view of a narrow nozzle cap for the blower of FIGS. 1A through 1B, in accordance with embodiments of the present disclosure; FIG. 4 is a schematic illustration of a power control module in accordance with embodiments of the present disclosure; FIG. 5 is a graph showing two operation modes of a blow molding tool according to the embodiments of the present disclosure; FIG. 6 is a flow diagram of a method of operating a blow tool in accordance with embodiments of the present disclosure; FIG. 7 is a flow diagram of a method of operating a blow tool in accordance with embodiments of the present disclosure; and FIG. 8 is a block diagram of an example of a computer system in accordance with embodiments of the present disclosure.Detailed DescriptionReference will now be made in detail to embodiments of the present invention, one or more examples of which are illustrated in the drawings. The word "exemplary" is used herein in the sense of "serving as an example, case, or illustration.". Any embodiment described herein as "exemplary" is not necessarily to be understood as preferred or advantageous over other embodiments. In addition, each example is illustrative and not limiting of the technique. Indeed, it will be apparent to those skilled in the art that modifications and variations can be made to the present technique without departing from the scope or spirit of the claimed technique. For example, features shown or described as part of one embodiment may be used with another embodiment to obtain yet another embodiment. It is therefore intended that the present disclosure cover such modifications and variations as fall within the scope of the appended claims and their equivalents. In the detailed description, numerical and letter-related designations are used to indicate features in the drawings. Like or similar labels have been used in the drawings and the specification to refer to like or similar parts of the invention.As used herein, the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another and are not intended to refer to the location or meaning of the individual components. The singular forms "a", "an" and "the / s" include plural referents unless the context clearly dictates otherwise. The terms "connected," "attached," "attached to," and the like refer to both direct connection, attachment, or attachment, and indirect connection, attachment, or attachment via one or more intermediary components or features, unless otherwise specified herein. As used herein, the terms "comprises," "comprising," "includes," "including," "has," "with," or any other variation thereof are intended to cover a non-exclusive inclusion. For example, an act, method, article, or device comprising a list of features is not necessarily limited to only those features, but may also comprise other features not expressly listed or associated with that act, method, article, or device. Unless expressly stated otherwise, "or" refers to an inclusive or not an exclusive or. For example, a condition A or B is satisfied when one of the following conditions is satisfied: A meets (or is present) and B does not meet (or is not present), A does not meet (or is not present) and B meets (or is present), and both A and B meet (or are present).Terms of approximation such as "about," "generally," "approximately," or "substantially" include values within ten percent greater or less than the stated value. When used in the context of an angle or direction, such terms include values within ten degrees greater or less than the indicated angle or direction. For example, "generally vertical" includes directions within ten degrees of vertical in each direction, such as clockwise or counter-clockwise.Improvements, other advantages, and solutions to problems are described below with respect to certain embodiments. However, the improvements, advantages, solutions to issues, and features that may result in an advantage, benefit, or solution occurring or becoming more pronounced are not to be understood as a key, required, or essential feature of any or all of the claims.When different nozzle attachments are added to a blow mold, this can generally negatively impact the performance of the blow mold. For example, some nozzle attachments may result in the speed of the blower connected to the motor decreasing, thereby decreasing the air output (e.g., in cubic feet per minute) of the blow tool. However, when the engine is operated with a constant power output, for example, by using a closed loop power control module, it can be ensured that the power of the blow molding tool remains constant regardless of whether a nozzle attachment is used and regardless of the type of the nozzle attachment.FIG. 1A is a perspective view of a blow mold in accordance with embodiments of the present disclosure. FIG. 1B shows a side view of the blow mold of FIG. 1A in accordance with embodiments of the present disclosure.In at least one exemplary embodiment, a blow mold 100 includes a blow mold housing 108 having an air inlet 102 and an air outlet 104. The blow mold 100 may also include a blow mold tube 109 that is detachably connected to the blow mold housing 108. The blow tool tube 109 may delimit at least a portion of the air outlet 104. The blow tool 100 is configured to generate an airflow along an airflow channel 106 extending between the air inlet 102 and the air outlet 104. For example, the airflow channel 106 may extend from the air inlet 102, through the blow tool housing 108 and the blow tool tube 109 to the air outlet 104, as shown in FIG. 1B.In at least one exemplary embodiment, blow mold 100 is a commercially available hand-held blow mold having a cordless, battery powered power source. The blow tool housing 108 includes, for example, a handle 115. A power source 116 may be removably connected to the blow tool housing 108. For example, the power source 116 may include one or more batteries that are removably connected to a portion of the handle 115 of the blow tool housing 108. In other exemplary embodiments, the blow mold 100 may include a wired electrical power source and / or a gas source. In other embodiments, the blow tool 100 may be provided as a standard backpack blow tool (not shown) that may be worn on the user's back and has a cordless battery power source.In at least one exemplary embodiment, blow mold 100 is configured to receive a nozzle attachment 126. The nozzle attachment 126 may be detachably connected to the blow tool tube 109 adjacent to the air outlet 104. The blow tool tube 109 may include, for example, a plurality of threads 124 configured to engage the nozzle attachment. In other embodiments, the nozzle attachment 126 may be otherwise secured to the blow tool tube 109, for example, by a snap-fit engagement. In still other example embodiments, the nozzle cap 126 may be integrally connected to the blow tool tube 109.In at least one exemplary embodiment, nozzle cap 126 is a standard nozzle, as shown in FIG. 1B. In other exemplary embodiments, various types of nozzle attachment 126 may be removably coupled to blow tool tube 109, as discussed below with respect to FIGS. 3A through 3B.FIG. 2 shows a cross-sectional view of a portion of the blower of FIGS. 1A through 1B, in accordance with embodiments of the present disclosure.In at least one embodiment, blow tool housing 108 may at least partially enclose components of blow tool 100, such as an airflow generation assembly 110 having a blower 112 and a motor 114 driving blower 112, as well as various other components. Power for operation of the airflow generating assembly 110 may be provided from the power source 116, for example, one or more batteries that are releasably connected to the blow tool housing 108.In at least one exemplary embodiment, airflow generation assembly 110 may have an axial configuration. For example, the blower 112 and the motor 114 may be located within the blow tool housing 108 between the air inlet 102 and the air outlet 104 and oriented along a central axis 120 of the airflow duct 106. Rotation of the motor 114 causes rotation of a motor shaft 122 that extends along the central axis 120. The motor shaft 122 is coupled to the blower 112. In this way, rotation of the motor shaft 122 causes rotation of the fan 112.In at least one example embodiment, blower 112 includes a hub 130 and a plurality of blades 132. The hub 130 may have a generally circular cross-section and extend along the central axis 120. The motor shaft 122 is connected to the hub 130 and / or a fan drive shaft 134 to allow rotation to be transmitted from the motor 114 to the hub 130 or fan drive shaft 134 and ultimately to the blades 132.In at least one example embodiment, control electronics, such as controller 200, is disposed within blow tool housing 108 and configured to control motor 114 and blower 112, as discussed in greater detail below with respect to FIG. 4. The control device 200 can be arranged, for example, within the blow-molding tool housing 108 adjacent to the handle 115.In at least one example embodiment, a trigger 118 may be disposed in the handle 115. The trigger 118 may be electrically connected to the motor 114, the power source 116, and / or the controller 200 and configured to control operation of the blow mold 100 by activating and deactivating the motor 114. In at least one exemplary embodiment, trigger 118 may be used by an operator to select and set a desired power output of blow tool 100. In other examples, the trigger 118 may be used by the operator to select and adjust the speed of the fan 112 of the motor 114.FIG. 3A is a perspective view of a flat nozzle attachment for the blow mold of FIGS. 1A through 1B in accordance with embodiments of the present disclosure. FIG. 3B is a perspective view of a narrow nozzle cap for the blower of FIGS. 1A through 1B in accordance with embodiments of the present disclosure.In at least one example embodiment, nozzle cap 126 is a flat nozzle cap (shown in FIG. 3A ). The flat nozzle cap has a first end 305 and a second end 310 opposite the first end 305. The flat nozzle attachment can be detachably connected to the blow tool tube 109 at the first end 305. In at least one example embodiment, the height of the flat nozzle attachment may decrease from the first end 305 toward the second end 310. Additionally or alternatively, the width of the flat nozzle attachment may increase from the first end 305 toward the second end 310. For example, the width of the flat nozzle cap may increase from a central portion of the flat nozzle cap toward the second end 310, as shown in FIG. 3A.In at least one example embodiment, nozzle cap 126 is a narrow nozzle cap (shown in FIG. 3B ). The narrow nozzle cap has a first end 320 and a second end 325 opposite the first end 320. The narrow nozzle attachment can be detachably connected to the blow tool tube 109 at the first end 320. In at least one exemplary embodiment, the diameter of the narrow nozzle cap decreases from the first end 320 toward the second end 325.In other exemplary embodiments, the nozzle attachment 126 includes a choke nozzle, a conical nozzle, a flared nozzle, a flared angle nozzle, or a trough attachment.FIG. 4 shows a schematic diagram of a power control module in accordance with embodiments of the present disclosure.In at least one example embodiment, controller 200 of blow mold 100 includes a closed loop power control module 400. The closed loop power control module 400 is configured to maintain a constant power output of the engine 114. The power output by the motor 114 may be constant, for example, regardless of whether the nozzle cap 126 is attached to the blow tool tube 109 and regardless of the type of the nozzle cap 126 attached to the blow tool tube 190, such as the flat nozzle cap (shown in FIG. 3A ) and the narrow nozzle cap (shown in FIG. 3B ). In at least one example embodiment, closed loop power control module 400 includes a proportional and integral ("PI") controller.In at least one example embodiment, closed loop power control module 400 receives a power setpoint 405. The power setpoint 405 may be a desired power output that is set by an operator of the blow mold 100. The power setpoint 405 may be set by the operator, for example, using the trigger 118, as described above with reference to FIG. 2. Additionally, a variation limit may be applied to the power set point 405 by a variation limit 410. The fluctuation limiter 410 receives the power command 405 and is configured to limit the rate of change of the voltage output by the motor 114 of the blow mold 100. For example, the output voltage of the motor 114 is increased over a period of time until the power set point 405 is reached.Additionally, the closed loop power control module 400 receives a measured power 415 output by the engine 114. The measured power 415 may be obtained by receiving a measured motor current 420 and a measured motor voltage 425 from the motor 114. The closed loop power control module 400 may be configured to filter the measured motor current 420 to obtain a smooth measurement. For example, the measured motor current 420 may be provided to a filter 430 to obtain a filtered current output 435.In at least one example embodiment, filter 430 is a low pass filter. The filter 430 may be, for example, an exponentially moving average filter ("EMA"). The EMA filter is a low pass filter that depends on the last input value and the previous output value. The EMA filter is based on the following equation: wherein α is determined by the following equation: wherein f c is a cut-off frequency and f s is a sampling frequency. In other examples, the filter 430 may be a Butterworth filter, a Czechbyscheff filter, or a simple moving average filter.With continued reference to FIG. 4, a multiplier 440 may receive the measured motor voltage 425 and the filtered current output 435. The multiplier 440 multiplies the measured motor voltage 425 and the filtered current output 435 to obtain the measured power 415.In at least one example embodiment, power setpoint 405 and measured power 415 are communicated to a summation module 445. The summation module 445 is configured to obtain a power difference 450 between the power setpoint 405 and the measured power 415. A control signal may be generated based on the power difference 450. For example, if there is no difference between the power setpoint 405 and the measured power 415, i.e., if the power difference 450 is about 0, the current operation of the blow molding tool 100 may be maintained. However, if there is a difference between the power setpoint 405 and the measured power 415, the operation of the blow tool 100 may be adjusted, for example, by adjusting the power output of the motor 114 as described further below.In at least one example embodiment, power difference 450 is applied to an amplifier 455 and / or an integrator 460. The amplifier 455 is configured to apply a gain to the power difference 450 to obtain a first signal 465. The power difference is integrated by the integrator 460 to obtain a second signal 470. The first signal 465 and the second signal 470 are combined at 475 to obtain a control signal 480.In at least one exemplary embodiment, control signal 480 is provided to an output limiter 485 and / or a fluctuation limiter 490. The output limiter 485 is configured to control a voltage of the control signal 480. For example, the output limiter 485 prevents a voltage value of the control signal 480 from exceeding a threshold value. Additionally or alternatively, the variation limiter 490 controls the rate of change of the voltage of the control signal 480. The variation limiter 490 may be similar or analogous to the variation limiter 410, for example.Additionally, the control signal 480 is output to the motor 114 at 495. The control signal 480 may command the motor 114 to adjust the power output from the blow tool 100 by adjusting the output voltage of the motor 114. For example, control signal 480 may cause the voltage provided to motor 114 to be increased or decreased based on the output of power limiter 485 and / or fluctuation limiter 490 to achieve power setpoint 405. In some embodiments, the control signal 480 includes a duty cycle command 498 that is output to the motor 114. In other embodiments, the power output by the motor 114 may be adjusted by changing the speed of the fan 112 of the motor 114. For example, the control signal 480 may increase the speed of the fan 112 when the measured power 415 is less than the power set point 405, or the control signal 480 may decrease the speed of the fan 112 when the measured power 415 is greater than the power set point 405. The closed loop power control module 400 of the controller 200 may continuously compare the power setpoint 405 and the measured power 415 to maintain a constant power output of the engine 114. While the power output by the motor 114 remains constant, the speed of the fan 112 may fluctuate (increase or decrease) to keep the power constant.FIG. 5 is a graph showing two operation modes of a blow molding tool according to the embodiments of the present disclosure.In at least one example embodiment, desired power range 500 includes an upper threshold 505 and a lower threshold 510. The upper threshold 505 is a function of the maximum revolutions per minute of the blower 112 and the power output by the motor 114. The lower threshold 510 is a function of the minimum revolutions per minute of the blower 112 and the power output by the motor 114. If the power output by the motor 114 is within the desired power range 500 defined by the upper threshold 505 and the lower threshold 510, then the power of the blow tool 100, such as the cubic feet per minute of air exiting the blow tool tube 109, has remained constant. When the power output is within the desired power range 500, the controller 200 may operate the blow tool 100 in the first mode. The first mode of operation may include a closed loop control of the speed of the fan 112 of the motor 114.In at least one example embodiment, controller 200 may adjust a speed setpoint of motor 114 when power delivered by motor 114 is outside desired power range 500, for example when delivered power falls below lower threshold 510. For example, the controller 200 may increase or decrease the speed of the fan 112 of the motor 114. Adjusting the speed of the fan 112 of the motor 114 may increase the power output of the motor 114 such that the power output is within the desired speed range 500. After adjusting the speed of the fan 112 of the motor 114, the controller 200 may continue operating in the first mode of operation, as discussed below with reference to FIG. 7.In at least one example embodiment, if power delivered by motor 114 falls below lower threshold 510, a low flow condition may be detected. A low flow condition may occur when a nozzle attachment, such as nozzle attachment 126, is connected to blow tool 100. When a low flow condition is detected, such as when the power output by the motor 114 falls below the lower threshold 510, the controller 200 may operate the motor in the second mode of operation, as discussed below in FIG. 6. The second mode of operation may be a closed loop for the power output of the motor 114.FIG. 6 shows a flow diagram of a method of operating a blow tool in accordance with embodiments of the present disclosure.In at least one exemplary embodiment, a method 600 of operating a blow tool, such as blow tool 100, includes setting a power setpoint at 605, measuring a power output at 610, and comparing the power output to the power setpoint at 615. The method 600 may also include determining whether the power output is below a threshold at 620. If the power output is below the threshold at 620, method 600 may include controlling the power output at 625. If the output power is not below the threshold of 620, method 600 may include controlling the speed of a fan of the motor at 630. One or more portions of method 600 may be executed by one or more computing devices, such as controller 200.In at least one example embodiment, adjusting a power setpoint at 605 includes adjusting a desired power output of engine 114. The power setpoint 405 may be set by, for example, the operator with the trigger 118, as described above in FIG. 2. Moreover, a variation limitation may be performed by the variation limiter 410 as shown and described in FIG. 4.In at least one example embodiment, measuring power output at 610 includes receiving measured power 415 output from engine 114. Receiving the measured power 415 may include receiving a measured motor current 420, receiving a measured motor voltage 425 from the motor 114, applying a filter to the measured motor current 420 using the filter 430 to obtain the filtered current output 435, and multiplying the measured motor voltage 425 by the filtered current output 435.In at least one example embodiment, comparing power output to power setpoint at 615 includes calculating power difference 450 between power setpoint 405 and measured power 415 at 445.In at least one exemplary embodiment, blow mold 100 has two modes of operation as described in FIG. 5. For example, the blow tool 100 may be configured to operate in the first mode when the measured power 415 is within the desired power range 500, and to operate in the second mode when the measured power 415 is outside the desired power range 500, for example below the lower threshold 510. The first mode of operation may include controlling the speed of the blower 112 at 630, as described below in FIG. 7.In at least one example embodiment, the second mode of operation includes adjusting the power output of the motor 114 as described in FIG. 4. For example, if the measured power 415 is below the lower threshold 510, the power difference 450 is amplified in the amplifier 455 to obtain the first signal 465. Additionally or alternatively, the integrator 460 integrates the power difference 450 to obtain the second signal 470. The first signal 465 and the second signal 470 are combined at 475 to obtain a control signal 480. The control signal 480 is then used to adjust the power output of the motor 114 as described above with respect to FIG. 4.In at least one example embodiment, after controlling power output at 625 or controlling speed of fan 112, method 600 returns to measure power output at 610. Accordingly, the method 600 may be executed by the controller 200 to continuously control the operation of the blow mold 100 until the operation of the blow mold 100 by the operator is ended.FIG. 7 shows a flow diagram of a method of operating a blow tool in accordance with embodiments of the present disclosure.In at least one example embodiment, first mode of operation includes operation of blow mold 100 according to a method 700. The method 700 includes receiving a speed setpoint at 707, measuring a speed output at 710, determining if the measured speed output matches the speed setpoint at 715, and adjusting the blower speed at 720 if the measured speed output does not match the speed setpoint at 715. One or more portions of method 700 may be executed by one or more computing devices, such as controller 200.In at least one example embodiment, receiving the speed setpoint at 705 includes receiving a desired speed set by the operator. For example, the operator may set and adjust the speed setpoint with the trigger 118.In at least one example embodiment, measuring the speed output at 710 includes measuring the speed of the engine fan 112. For example, a sensor may be disposed in the blow tool housing 108 to measure the speed of the blower 112.In at least one example embodiment, determining whether output speed matches speed setpoint (715) comprises determining whether there is a difference between measured speed output and speed setpoint. If there is no difference, for example, if the measured speed is equal to the speed setpoint, method 700 may return to measuring speed at 710. For example, the rotational speed of the blower 112 is continuously monitored. If there is a difference between the measured speed output and the speed setpoint, the blower speed may be adjusted in step 720.In at least one example embodiment, adjusting blower speed in step 720 includes sending a control signal from controller 200 to motor. The control signal may command the motor 114 to increase the speed of the fan 112 when the measured speed output is less than the speed setpoint, or decrease the speed of the fan 112 when the measured speed output is greater than the speed setpoint.In at least one example embodiment, after adjusting blower speed at 720, method 700 returns to measuring speed output at 710. In this way, the controller 200 continuously monitors the speed of the fan 112 to ensure that the speed of the fan 112 is maintained at the speed set point.FIG. 8 is a block diagram of an example of a computer system in accordance with embodiments of the present disclosure.In at least one example embodiment, a computer system 800 may include one or more computing devices 802. The one or more computing devices 802 may / may include, for example, at least one of the controllers 200. Each of the one or more computing devices 802 may include one or more processors 804 and one or more storage devices 806. The one or more processors 804 may include any suitable processing device, such as a microprocessor, microcontroller, integrated circuit, logic device, or other suitable processing device. The one or more storage devices 806 may include one or more computer readable media including, but not limited to, non-transitory computer readable media, RAM, ROM, hard drives, flash drives, or other storage devices.The one or more storage devices 806 may / may store information accessible by the one or more processors 804, including computer readable instructions 808 executable by the one or more processors 804. The instructions 808 may be any instructions that, when executed by the processor or processors 804, cause the processor or processors 804 to perform acts. The instructions 808 may be software written in any programming language or may be embodied in hardware. In some embodiments, the instructions 808 may be executed by the one or more processors 804 to cause the one or more processors 804 to perform acts, such as the acts for generating execution tool and other scans, to determine tracking indicators according to the processing stages of the processing cycle using a plurality of cutting tools, generate state data and mapping data associated with cutting tools, detect missing cutting tools, and initiate control acts associated with missing control elements as described above, and / or other acts or functions of the one or more computing devices 802.The memory device(s) 806 may also store data 810 that may be accessed by the one or more processors 804. The data 810 may include, for example, state data, mapping data, processing cycle and / or stage data, and user interface data, etc., as described herein. The data 810 may include one or more tables, a function or functions, an algorithm or algorithms, a model or models, an equation or equations, etc., in accordance with the example embodiments of the present disclosure.The computing device(s) 802 may also include a communication interface 812, for example, for communication with the other components of the system. Communication interface 812 may include any suitable components for interfacing with one or more networks, such as transmitters, receivers, ports, controllers, antennas, or other suitable components.The technique described herein relates to computer-based systems and actions performed by computer-based systems, as well as information sent to and from computer-based systems. Those skilled in the art will understand that the inherent flexibility of computer-aided systems allows a wide variety of possible configurations, combinations and distributions of tasks and functions between and among the components. For example, the processes described herein may be performed with a single computing device or with multiple computing devices in combination. Databases, memories, commands, and applications may be executed on a single system or distributed across multiple systems. Distributed components may operate sequentially or in parallel.Further aspects of the invention are provided by one or more of the following embodiments:A blow mold includes a blow mold housing, a motor for driving a blower disposed in the blow mold housing, and a controller disposed in the blow mold housing and electrically coupled to the motor to control a power output of the motor. The control device is configured to carry out a plurality of activities. The plurality of operations includes receiving a power setpoint, receiving a measured power, comparing the power setpoint and the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting the power output of the motor based on the control signal.The blow tool of one or more embodiments, wherein the plurality of operations further comprises applying a variation limit to the received power setpoint.The blow tool of one or more embodiments, wherein receiving the measured power comprises receiving a current output from the motor, applying a filter to the current output to obtain a filtered current output, receiving a voltage output from the motor, and multiplying the filtered current output and the voltage output by the motor to obtain the measured power.The blow tool of one or more embodiments, wherein the filter comprises a low pass filter.The blow tool of one or more embodiments, wherein the filter comprises an exponentially moving average filter.The blow tool of one or more embodiments, wherein generating the control signal comprises applying a gain to the power difference to obtain a first signal, integrating the power difference to obtain a second signal, and combining the first signal and the second signal to obtain the control signal.The blow molding tool of one or more embodiments, wherein generating the control signal further comprises controlling a voltage of the control signal via an output limiter and controlling a rate of change of the voltage of the control signal via a variation limiter.The blow tool of one or more embodiments, wherein adjusting the power output of the motor comprises adjusting the voltage output of the motor based on the control signal.The blow tool of one or more embodiments, wherein adjusting the power output of the motor comprises adjusting the speed of the blower.The blow tool of one or more embodiments, wherein adjusting the speed of the fan includes increasing the speed of the fan when the measured power is less than the power set point and decreasing the speed of the fan when the measured power is greater than the power set point.The blow molding tool of one or more embodiments, wherein the controller comprises a proportional and integral controller.The blow tool of one or more embodiments, wherein the controller is configured to maintain a constant power output.The blow tool of one or more embodiments, wherein the plurality of operations is a first plurality of operations, and the controller is further configured to compare the measured power to a desired power range and operate in a first mode when the measured power is within the desired power range. The first mode of operation includes a second plurality of operations. The second plurality of operations includes receiving a speed setpoint of a fan of an engine, receiving a measured speed of the fan of the engine, comparing the speed setpoint to the measured speed to obtain a speed difference, and adjusting a speed of the fan of the engine based on the obtained speed difference. The controller is also configured to operate in a second mode when the measured power is outside the desired power range. The second mode of operation includes the first plurality of operations.A method for controlling a motor of a blow mold includes receiving a power setpoint, receiving a measured power, comparing the power setpoint and the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting a power output of the motor based on the control signal.The method of one or more embodiments further comprising applying a variation limit to the received power setpoint.The method of one or more embodiments, wherein receiving the measured power comprises receiving a current output from the motor, applying a filter to the current output to obtain a filtered current output, receiving a voltage output from the motor, and multiplying the filtered current output and the voltage output by the motor to obtain the measured power.The method of one or more embodiments, further comprising applying a gain to the power difference to obtain a first signal, integrating the power difference to obtain a second signal, and combining the first signal and the second signal to obtain the control signal.The method of one or more embodiments, wherein generating the control signal further comprises controlling a voltage of the control signal via an output limiter and controlling a rate of change of the voltage of the control signal via a variation limiter.The method of one or more embodiments, wherein adjusting the power output of the motor comprises adjusting a voltage output of the motor based on the control signal.The method of one or more embodiments further comprising comparing the measured power to a desired power range, operating in a first mode when the measured power is within the desired power range, and operating in a second mode when the measured power is outside the desired power range. The first mode includes receiving a speed setpoint of a fan of a motor, receiving a measured speed of the fan of the motor, comparing the speed setpoint to the measured speed to obtain a speed difference, and adjusting a speed of the fan of the motor based on the obtained speed difference. The second mode of operation includes receiving the power setpoint, receiving the measured power, comparing the power setpoint and the measured power, generating the control signal, and adjusting the power output.In this written description, the invention, including the best mode, is disclosed by way of example to enable one skilled in the art to practice the invention, including making and using devices or systems and performing integrated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims, provided they include construction elements that do not differ from the literal language of the claims, or provided they include equivalent construction elements with insubstantial differences from the literal language of the claims.

Claims

A blow tool, comprising: a blow tool housing; a motor for driving a blower disposed in the blow tool housing; and a controller disposed in the blow tool housing and electrically connected to the motor to control a power output of the motor, wherein the controller is configured to perform a plurality of operations, the plurality of operations comprising: receiving a power setpoint, receiving a measured power, comparing the power setpoint with the measured power to obtain a power difference, generating a control signal based on the power difference, and adjusting the power output of the motor based on the control signal.The blow tool of claim 1, wherein the plurality of operations further comprises applying a variation limit to the received power setpoint.The blower of claim 1, wherein receiving the measured power comprises: receiving a current output from the motor; applying a filter to the current output to obtain a filtered current output; receiving a voltage output from the motor; and multiplying the filtered current output and the voltage output by the motor to obtain the measured power.A fan according to claim 3, wherein the filter comprises a low pass filter or an exponentially moving average filter.The blower of claim 1, wherein generating the control signal comprises: applying a gain to the power difference to obtain a first signal; integrating the power difference to obtain a second signal; combining the first and second signals to obtain the control signal; controlling a voltage of the control signal via an output limiter; and controlling a rate of change of the voltage of the control signal via a variation limiter.The blow tool of claim 1, wherein adjusting the power output of the motor comprises adjusting a voltage output of the motor based on the control signal.The blow tool of claim 1, wherein: adjusting the power output of the motor comprises adjusting the speed of the fan; and adjusting the speed of the fan comprises: increasing the speed of the fan when the measured power is below the power setpoint and decreasing the speed of the fan when the measured power is greater than the power setpoint.The blower of claim 1, wherein the controller is configured to maintain a constant power output.The blower of claim 1, wherein: the plurality of operations is a first plurality of operations; and the controller is further configured to: compare the measured power to a desired power range and operate in a first mode when the measured power is within the desired power range, wherein the first mode comprises a second plurality of operations, and the second plurality of operations comprises: receiving a speed setpoint of a blower of a motor, receiving a measured speed of the blower of the motor, comparing the speed setpoint to the measured speed to obtain a speed difference, and adjusting a speed of the blower of the motor based on the obtained speed difference; and operating in a second mode when the measured power is outside the desired power range, the second mode comprising the first plurality of operations.A method of controlling a motor of a blow tool, comprising: receiving a power setpoint; receiving a measured power; comparing the power setpoint and the measured power to obtain a power difference; generating a control signal based on the power difference; and adjusting the power output of the motor based on the control signal.The method of claim 10, wherein receiving the measured power comprises: receiving a current output from the motor; applying a filter to the current output to obtain a filtered current output; receiving a voltage output from the motor; and multiplying the filtered current output and the voltage output by the motor to obtain the measured power.The method of claim 10, further comprising: applying a gain to the power difference to obtain a first signal; integrating the power difference to obtain a second signal; and combining the first and second signals to obtain the control signal.The method of claim 10, wherein generating the control signal further comprises: controlling a voltage of the control signal via an output limiter; and controlling a rate of change of the voltage of the control signal via a variation limiter.The method of claim 10, wherein adjusting the power output of the motor comprises adjusting a voltage output of the motor based on the control signal.The method of claim 10, further comprising: comparing the measured power to a desired power range; operating in a first mode when the measured power is within the desired power range, the first mode comprising: receiving a speed setpoint of a fan of a motor, receiving a measured speed of the fan of the motor, comparing the speed setpoint to the measured speed to obtain a speed difference, and adjusting a speed of the fan of the motor based on the obtained speed difference; and operating in a second mode when the measured power is outside the desired power range; wherein the second mode comprises receiving the power setpoint, receiving the measured power, comparing the power setpoint and the measured power, generating the control signal, and adjusting the power output.

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