Method for estimating the time during which an endothermic motor operates at a predetermined speed by measuring with an inductive sensor and a device for implementing the method

Abstract

A method for estimating the time it takes for a tool's endothermic motor to operate at a predetermined rotational speed using measurements taken by an inductive sensor is described, along with an apparatus for implementing the method. The method specifically includes the steps of: cyclically measuring a total time interval at a preset sampling period by initiating the measurement of the total time interval when a first peak change in the electromagnetic field is sensed and terminating the measurement of the total time interval when a last peak change in the electromagnetic field is sensed, wherein the first peak and the last peak are the start and end points of a peak sequence having a predetermined number of consecutive peaks, the number of peaks being at least equal to 6 and a positive integer being a least common multiple of 2 and 3. The method is based on the expectation that the tool primarily operates at a known idle speed and a known maximum speed. Compartments with specific frequency ranges are formed, two compartments with the most frequently measured frequencies are selected, and various candidate speed values ​​are compared with the known idle and maximum speed values ​​to determine low-speed and high-speed conversion coefficients between the speed and the measured pulse frequencies. Based on these conversion coefficients, each measurement frequency is associated with a speed range, and the operating time within that respective speed range is determined.

Description

Technical Field

[0001] The present invention relates to a method for estimating the time it takes for a heat-absorbing motor to operate at a given rotational speed, and the method is particularly applicable to heat-absorbing motors for garden tools. Background Technology

[0002] Some accessories (i.e. aftermarket equipment) are known to be suitable for connection to gardening tools (such as chainsaws, shrub cutters, or blowers) actuated by heat-absorbing motors to automatically measure their operating hours.

[0003] One type of such accessory includes an inductive sensor for making the runtime measurement. This inductive sensor allows for the measurement of changes in the electromagnetic field resulting from the passage of the current required to generate a spark in the combustion chamber of the heat-absorbing motor and / or changes in the electromagnetic field generated by magnets present in the freewheel of the heat-absorbing motor. Inductive sensors are particularly advantageous in this type of accessory because they have very low (if not zero) energy consumption, and therefore they allow for the manufacture of long-lasting battery-powered devices.

[0004] Typically, sensors are only used to detect whether a motor is on or off. However, measuring the total operating time of a motor provides limited information for monitoring tool wear. For example, a tool whose motor runs at maximum speed throughout its operation will inevitably show greater wear than a tool that runs for the same number of hours under less load conditions.

[0005] A sensor can measure the change in the magnetic field (in the form of peaks) caused by the spark plug's firing, and this change directly represents the revolutions per minute (rpm). For example, the number of sparks in a two-stroke stroke per unit time corresponds to the number of revolutions per unit time. Therefore, sensing the number of sparks will determine the frequency of the rotational speed (i.e., revolutions per unit time), which can then be easily converted to revolutions per minute (rpm).

[0006] However, depending on the position of the accessory equipped with the sensing sensor on the tool, or better yet, its position on the tool can be located (considering that its positioning is sometimes mandatory due to the shape of the tool), other electromagnetic field changes that overlap with the electromagnetic field changes caused by the spark can also be sensed (mainly due to the rotation of the magnet of the motor's freewheel).

[0007] Furthermore, the intensity of the electromagnetic field changes caused by the freewheel depends on the position and orientation of the sensor relative to the motor. Moreover, these changes are not always linearly proportional to the motor's revolutions throughout its entire operating speed range.

[0008] Therefore, this type of problem makes it impossible to simply calculate the rotational speed based on counting the changes in the magnetic field (i.e., the peak values ​​of the magnetic field changes).

[0009] One object of the present invention is to overcome the disadvantages of known technologies within the scope of reasonable and affordable solutions requiring limited computation time. This object is achieved by the features of the invention as set forth in the independent claims. The dependent claims list preferred and / or particularly advantageous aspects of the invention. Summary of the Invention

[0010] The present invention provides a method for estimating the time for a tool's heat-absorbing motor to operate at a predetermined rotational speed by means of measurements taken by a sensing sensor.

[0011] The method includes the following steps:

[0012] - Within a preset sampling period, the total time interval is measured cyclically by initiating the measurement of the total time interval when the first peak of the electromagnetic field change is sensed and terminating the measurement of the total time interval when the last peak of the electromagnetic field change is sensed. The first peak and the last peak are the start and end points of a peak sequence having a predetermined number of consecutive peaks, which is at least equal to 6 and is a positive integer that is a least common multiple of 2 and 3.

[0013] - Obtain their respective frequencies from the total measured time intervals.

[0014] - Makes multiple preset frequency ranges available for the total time interval being measured.

[0015] - Each time the total time interval containing frequencies falling within the preset frequency range is measured, the count of occurrences of the corresponding preset frequency range is increased by 1.

[0016] - Select two preset frequency ranges with the highest frequency of occurrence from multiple preset frequency ranges. The preset frequency range with the lowest frequency represents the range with the minimum speed, and the preset frequency range with the highest frequency represents the range with the maximum speed.

[0017] - The total threshold frequency is calculated by taking the arithmetic mean between a frequency in the range of at least the minimum speed and a frequency in the range of the maximum speed.

[0018] - Determine multiple correction coefficients, each obtained by dividing the number of peaks in the peak sequence by 1 and by each of the positive integers whose number of peaks is the least common multiple.

[0019] - Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the minimum speed frequency range.

[0020] - Compare the calculated rotational frequency value with a preset reference frequency range that indicates the idle speed of the heat absorption motor.

[0021] - Store the correction factor for low speed as the rotational frequency that falls within the reference frequency range of the indicator heat absorption motor's idle speed, which is one of the multiple correction factors.

[0022] - The representative rotational frequency for each preset frequency range below the threshold frequency is calculated by multiplying the frequency value of each range by a low-speed correction factor.

[0023] - Store the calculated representative rotation frequency,

[0024] - Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the maximum speed frequency range.

[0025] - Compare the calculated rotational frequency value with a reference frequency range that indicates the maximum operating frequency of the heat absorption motor.

[0026] - Store the correction coefficients corresponding to the rotational frequencies that fall within the preset frequency range for the maximum operation of the heat absorption motor as high-speed correction coefficients.

[0027] - The representative rotational frequency for each frequency range above the threshold frequency is calculated by multiplying the frequency values ​​for each range above the threshold frequency by a high-speed correction factor.

[0028] - Store the calculated representative rotation frequency, and

[0029] - The running time at which the motor has been running at the rotational frequency of each frequency range is determined by multiplying the number of occurrences of each frequency range by the value of the preset sampling period.

[0030] This approach enables a method that can accurately estimate the operating time of a motor at an approximate given rotational speed based on information (i.e., the unique information based on changes in the magnetic field measured by the sensing sensor), or, if the preset frequency range is particularly small, estimate the operating time of the motor at a precise rotational speed. Specifically, this method is based on the fact that when a change in the magnetic field generated by the heat-absorbing motor is measured, three main scenarios are possible depending on the position and orientation of the sensing sensor and the rotational speed.

[0031] The first scenario is that each peak in the magnetic field is caused by arcing. This first scenario... Figure 5 The image used to illustrate this is a graph showing the change in magnetic field strength over time, where the peak value caused by ignition is represented by PS.

[0032] The second scenario involves the magnetic field change caused by the rotation of the freewheel's magnet being inserted between the two peaks of the magnetic field change caused by the arcing. This second scenario... Figure 6and Figure 7 The graph shows the change in magnetic field strength over time, where the peak value caused by ignition is represented by PS and the peak value caused by the rotation of the free wheel is represented by PW.

[0033] The third scenario is that the two magnetic field changes caused by the rotation of the magnet of the free wheel are inserted between the peak values ​​of the two magnetic field changes caused by the ignition.

[0034] Therefore, given that typically one of the electromagnetic field change peaks measured in each, two, or three measurements is due to a sparking-induced electromagnetic change peak, by measuring the time interval between a positive integer number (the least common multiple of 2 and 3, i.e., 6) of consecutive peaks, it is ensured that the time interval between at least two electromagnetic field change peaks due to sparking can be sensed within each sampling period. Thus, in the first, second, and third cases, it is ensured that the time interval between at least two electromagnetic field change peaks due to sparking, which indicates the motor's revolutions, can be sensed. Experimental data also indicate that under some less frequent conditions, it is possible that more than two magnetic field changes due to interference from the rotation of the free wheel may be inserted between two magnetic field changes due to sparking. Therefore, for example, to improve the versatility of the method, the total time interval of the consecutive peak sequences can be optionally measured, where the number of consecutive peak sequences is a least common multiple of 2, 3, and 4 (i.e., 12), or the number of consecutive peak sequences is a least common multiple of 2, 3, 4, and 5 (i.e., 60).

[0035] Therefore, it is essentially important to measure the changes in the electromagnetic field while considering the peak sequence, which is the least common multiple of the possible distances between two consecutive peaks caused by arcing.

[0036] Measuring 6 peaks per cycle allows for optimal accuracy while saving energy, as it consumes less energy compared to recording 12 or 60 peaks per sampling period.

[0037] Furthermore, although this method cannot accurately calculate the rotational speed during the transition from one situation to another, the motor is always at its maximum or minimum speed during the use of these tools, and remains at the intermediate speed for a short time when the aforementioned transition occurs, and the transition is so rapid that the error is completely irrelevant in the calculation of the total number of hours used.

[0038] One aspect of the present invention provides a method comprising the following steps:

[0039] - Makes a database available for various types of tools equipped with heat-absorbing motors, wherein each type of tool is associated with a reference frequency range indicating the maximum operating frequency of the heat-absorbing motor for that type of tool.

[0040] - Allows selection of one type of tool from a database of multiple tool types, and

[0041] - Use the reference frequency range of the maximum operating frequency of the heat absorption motor associated with the selected type of tool to perform a comparison between the calculated value of the rotational frequency and the preset frequency range of the maximum operating frequency of the heat absorption motor.

[0042] In this way, the application of this method can be extended to several tools using only a single device, since not all tools have the same maximum rotational speed. Furthermore, this feature allows for greater accuracy of the method relative to a single and wide range of reference frequencies used to indicate the maximum operation of the heat-absorbing motor.

[0043] According to another aspect of the invention, measuring the total number of at least one predetermined time interval may include the step of accelerating the heat-absorbing motor of the tool from idle speed to maximum speed at least once.

[0044] The present invention also provides a device for a heat-absorbing motor of a delay estimation tool to operate at a predetermined rotational speed for a certain period of time, the device comprising a data acquisition device having:

[0045] -Inductive sensor,

[0046] -Storage unit,

[0047] - Wireless transmitter,

[0048] - Power supply battery, and

[0049] - An electronic control and command unit, operably connected to the sensing sensor, wireless transmitter, and storage unit, and configured to:

[0050] The total time interval is measured cyclically within a preset sampling period by initiating the measurement of the total time interval when the first peak of the electromagnetic field change is sensed and terminating the measurement of the total time interval when the last peak of the electromagnetic field change is sensed. The first peak and the last peak are the start and end points of a peak sequence, which has a predetermined number of consecutive peaks. This number of peaks is at least equal to 6 and is a positive integer that is a least common multiple of 2 and 3.

[0051] o Obtain their respective frequencies from the total measured time intervals.

[0052] o Makes multiple preset frequency ranges available for the total time interval being measured, and

[0053] Each time the total time interval containing frequencies falling within the preset frequency range is measured, the count of occurrences of the corresponding preset frequency range is increased by 1.

[0054] The device also includes a remote control, which has:

[0055] - Wireless receiver

[0056] - A processing unit, operatively connected to a wireless receiver, and configured to:

[0057] o Select two preset frequency ranges with the highest frequency of occurrence from multiple preset frequency ranges. The preset frequency range with the lowest frequency represents the range with the minimum speed, and the preset frequency range with the highest frequency represents the range with the maximum speed.

[0058] The total threshold frequency is calculated by taking the arithmetic mean between a frequency in the range of minimum speed and a frequency in the range of maximum speed.

[0059] o determines multiple correction coefficients, each obtained by dividing the number of peaks in the peak sequence by 1 and by each of the positive integers whose least common multiple is the number of peaks.

[0060] Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the minimum speed frequency range.

[0061] The calculated rotational frequency value is compared with a preset reference frequency range that indicates the idle speed of the heat absorption motor.

[0062] o Store the correction coefficients from among the multiple correction coefficients that correspond to the rotational frequency falling within the reference frequency range of the indicator heat absorption motor's idle speed as low-speed correction coefficients.

[0063] The representative rotational frequency for each preset frequency range below the threshold frequency is calculated by multiplying the frequency value of each range by a low-speed correction factor.

[0064] o stores the calculated representative rotation frequency,

[0065] Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the maximum speed frequency range.

[0066] The calculated rotational frequency value is compared with a reference frequency range that indicates the maximum operating range of the heat absorption motor.

[0067] o Store the correction coefficients corresponding to the rotational frequencies that fall within the preset frequency range for the maximum operation of the heat absorption motor as high-speed correction coefficients.

[0068] The representative rotational frequency for each frequency range above the threshold frequency is calculated by multiplying the frequency values ​​for each range above the threshold frequency by a high-speed correction factor.

[0069] o stores the calculated representative rotation frequency, and

[0070] The running time at which the motor has been running at the rotational frequency of each frequency range is determined by multiplying the number of occurrences of each frequency range by the value of the preset sampling period.

[0071] This solution provides a device that can accurately estimate the operating hours of its associated tools, and because the energy consumption caused by data processing is diverted to a remote device, the device requires less frequent maintenance than the data acquisition device's battery, compared to the case where the data acquisition device itself processes the data.

[0072] According to another aspect of the invention, the remote device may include a display device, and the processing unit is configured to display a report on the display device, the report showing the associated running time for each calculated representative rotation frequency value. Attached Figure Description

[0073] Other features and advantages of the invention will become more apparent after reading the following description, provided by way of non-limiting example, with the aid of the accompanying drawings.

[0074] Figure 1 This is a schematic diagram of a device according to the present invention for a delay estimation tool, showing the time during which the heat-absorbing motor has been running at a predetermined rotational speed.

[0075] Figure 2 This is a view of a tool equipped with a heat-absorbing motor. Figure 1 The data acquisition device of the equipment is installed on the heat absorption motor.

[0076] Figure 3 This is a histogram showing the frequency of occurrences of the total time interval measured by the acquisition device. This histogram can be obtained from... Figure 1 The device is remotely processed. The X-axis of this histogram represents frequency (measured in Hertz), and the Y-axis represents the number of occurrences.

[0077] Figure 4 This is a schematic diagram of a report that can be processed by a remote device of the device according to the invention.

[0078] Figure 5 When the data acquisition device only senses changes in the electromagnetic field caused by arcing, the distance... Figure 2 An image showing the change in the electromagnetic field at a predetermined distance from the heat-absorbing motor of the tool. The Y-axis of the image represents the increase in the intensity of the electromagnetic field as measured by the inductive sensor according to the invention (and thus in volts V), and the X-axis represents the time of increase T.

[0079] Figure 6When the data acquisition device senses changes in the electromagnetic field caused by ignition and changes in the electromagnetic field caused by the motor's freewheel, the distance... Figure 2 An image showing the change in the electromagnetic field at a predetermined distance from the heat-absorbing motor of the tool. Specifically, the image illustrates a situation where there is a peak in the electromagnetic field between two peaks caused by arcing, due to the rotation of the motor's freewheel. The Y-axis of the image represents the increase in the intensity of the electromagnetic field as measured by the inductive sensor according to the invention (and thus in volts V), and the X-axis represents the time of increase T.

[0080] Figure 7 It is based on Figure 6 The image depicts the electromagnetic field changes under the circumstances described, illustrating the preset sampling period ΔC and the total time interval ΔT according to the invention. Detailed Implementation

[0081] A device for estimating the time it takes for a heat-absorbing motor of an instrument to operate at a predetermined rotational speed is generally represented by 1, i.e., operating approximately at a predetermined rotational speed, particularly at at least one of a minimum rotational speed and a maximum rotational speed.

[0082] In particular, this estimate is delayed, meaning it is not real-time during the operation of the heat-absorbing motor.

[0083] The tool is preferably a garden tool, such as a chainsaw, a blower (shown as reference numeral 5 in the accompanying drawings), a shrub cutter, a hedge cutter, a lawn mower, or an electric hoe.

[0084] These tools are equipped with a heat-absorbing motor, such as a two-stroke type, which is housed in a protective crankcase 10, for example, made of plastic material. The protective crankcase may also provide a gripping part (e.g., a handle) for the tool.

[0085] During use, the engine operates almost continuously at either maximum or minimum rotational speed.

[0086] The device 1 includes a data acquisition device 15, which is provided with a housing 20 (e.g., a box-shaped housing) and a sensing sensor 25 capable of measuring changes in magnetic field and / or electromagnetic field is housed inside the housing 20.

[0087] The sensing sensor comprises a spirally wound conductive wire and / or a coil made of conductive material.

[0088] In the case of a heat-absorbing motor, this change in electromagnetic field is mainly caused by the current passing through the corresponding wires of the motor to generate a spark in the combustion chamber, and / or by the rotation of the motor's freewheel.

[0089] The acquisition device 15 includes a storage unit housed directly within the housing 20. Specifically, the storage unit includes a volatile storage device 30 (commonly referred to as RAM) and a non-volatile storage device 35.

[0090] It is worth noting that volatile storage means that if no power is supplied to the storage device, the data stored in it will be lost, while non-volatile storage is designed to retain the stored data even if no power is supplied to it.

[0091] The acquisition device 15 also includes a wireless transmitter (e.g., a Bluetooth or WLAN type wireless transmitter) housed in the housing 20. The acquisition device 15 preferably also includes a transceiver 40 (e.g., a Bluetooth or WLAN type transceiver) housed in the housing 20 to also receive external commands.

[0092] In addition, the acquisition device 15 includes an electronic control and command unit 45, which is operatively connected to the sensing sensor 25, the wireless transmitter (i.e., the wireless transceiver 40), and the storage unit (i.e., the volatile storage device 30 and the non-volatile storage device 35), and is also housed in the housing 20.

[0093] The data collection device 15 (i.e., its components) is powered by a power source (e.g., battery 50) housed in the housing 20. Battery 50 is, for example, a button cell.

[0094] Preferably, the sensing sensor 25 is powered by the battery 50.

[0095] Device 1 also includes a remote device 55 configured to wirelessly interact with acquisition device 15. The remote device 55 may include a wireless receiver and a processing unit 60 connected to the wireless receiver and configured to process data acquired by the acquisition device. The remote device preferably includes a wireless transceiver 65 (e.g., of the Bluetooth or WLAN type) to both receive data from the acquisition device and send commands.

[0096] The remote device 55 may be, for example, a smartphone.

[0097] Device 1 may also include another remote device 70 equipped with a wireless transceiver 75 and a processing unit 80, the processing unit 80 being configured to process data acquired by the acquisition device. In this case, the remote device 55 will include a wireless transceiver configured to transmit data acquired by the acquisition device to the other remote device, and the processing unit will be configured to only transmit and receive data from the acquisition device 15 and data from the other remote device, and it will not be configured to process data from the acquisition device.

[0098] The other remote device could be, for example, a computer connected to the remote device via the Internet.

[0099] In both cases, the remote device 55 includes a display device 85, such as an electronic display. Alternatively, the other remote device may include a display device in the form of an electronic display.

[0100] The aforementioned device 1 is configured to perform a method for estimating the time during which the heat-absorbing motor of the tool operates at a predetermined rotational speed (i.e., approximately at a predetermined rotational speed), particularly at at least one of the minimum and maximum rotational speeds.

[0101] In particular, this estimate is delayed, meaning it is not real-time during the operation of the heat-absorbing motor.

[0102] Specifically, the method includes a sequence of steps related to acquiring and storing data, executed, for example, by the electronic control and command unit 45 of the acquisition device 15, and a sequence of steps related to processing the acquired data, executed, for example, by the processing unit 60 of the remote device 55 and / or by the processing unit 80 of another remote device 70. The method may also include, for example, a series of steps performed by the remote device 55, i.e., its display device 85, to display the processed data.

[0103] To perform this method, it is necessary to position the sensing sensor 25 (i.e., the acquisition device on which the sensing sensor 25 is provided) within a predetermined distance from the tool's heat-absorbing motor so that the sensing sensor can pick up the magnetic field changes generated by the operation of the heat-absorbing motor. For example, this distance is less than 10 cm. In particular, it is convenient to fasten the sensing sensor 25 (i.e., the acquisition device) to the tool's protective crankcase 10.

[0104] The sequence of steps related to data acquisition and storage includes the following steps: cyclically measuring the total time interval ΔT between the first and last peak values ​​of the electromagnetic field within a preset sampling period ΔC, wherein the preset sampling period ΔC is greater than the total time interval ΔT, i.e., greater than the maximum measurable total time interval (see [reference]). Figure 7 For example, the preset sampling period ΔC can be set to 250ms to allow for an optimal balance between power consumption and measurement accuracy.

[0105] The step of cyclically measuring the total time interval ΔT within a sampling period ΔC can be manually initiated by the operator using a suitable manual command to actuate the acquisition device. Alternatively, this actuation can occur automatically based on monitoring eddy currents within the inductive sensor, generated by changes in the electromagnetic field caused by the operation of a heat-absorbing motor. For example, the actuation of the cyclic measurement begins when a predetermined change in the electromagnetic field is reached within a given time period.

[0106] The first and last peaks are the start and end points of a peak sequence PS, PW with a predetermined number of consecutive peaks (i.e., closely spaced consecutively). The number of peaks in the sequence is a positive integer that is at least 6 and at least a least common multiple of 2 and 3.

[0107] To allow for an optimal balance between power consumption and measurement accuracy, in the illustrated embodiment (see...) Figure 7 The number of peaks is 6, therefore it is the least common multiple of 2 and 3.

[0108] It is worth noting that peak values ​​PS and PW indicate electromagnetic field variations of significant intensity at a predetermined threshold. This threshold is greater than the average magnetic field strength measured during the operation of the heat-absorbing motor.

[0109] Furthermore, the start and end of the total time interval ΔT measurement occur in the downward portion of the corresponding peak. As shown in the figure, the peaks PS and PW can be identified as electromagnetic field changes, which have an upward portion, followed by a portion with a substantially constant intensity, and then a downward portion.

[0110] In detail, this step thus provides a reduced gradient strength for sensing the electromagnetic field. Therefore, the electronic control and command unit of the acquisition device is configured to identify the changing reduced gradient in the electromagnetic field.

[0111] Alternatively or additionally, it may be possible to provide a sensing that indicates the occurrence of a peak value when the electromagnetic field value drops below a predetermined threshold after a (immediately following) previous increase is measured relative to a threshold.

[0112] In practice, the method provides that the electronic control and command unit is configured to, when it senses the first peak in the manner described, begin measuring the total time interval ΔT within the sampling period ΔC, and continuously increment the value of the meter by 1 each time it senses a peak PS, PW. Once the meter reaches a value equal to the number of peaks in the peak sequence, the measurement of the total time interval is interrupted, the data is stored, and the measurement of electromagnetic field changes is interrupted until a new sampling period ΔC begins.

[0113] The method described in this paper only measures the time interval between the first and last peaks of the peak sequence PS and PW, and does not provide the intensity or duration of the peaks. This allows for significant energy savings.

[0114] Next, the sequence of steps related to acquiring and storing data may include, preferably, storing the value of the measured total time interval ΔT in volatile memory.

[0115] Then, the sequence of steps related to data acquisition and storage includes the step of obtaining the respective frequencies from the total time intervals measured.

[0116] Specifically, as is known, the frequency is calculated by dividing 1 by the total time interval being measured, which has a value measured in seconds. In this way, a value in Hertz (i.e., s) is obtained. -1 (Frequency value).

[0117] This method makes multiple preset frequency ranges RF1, RF2, RF3, RF4, RF5, RF6, and RF7 available for the measured total time interval ΔT. That is, the method makes multiple meters available, each associated with a preset frequency range of the total time interval. For example, each frequency range has an amplitude of 5 Hz, and the range as a whole starts at 20 Hz and ends at 70 Hz.

[0118] The values ​​of the preset frequency ranges RF1, RF2, RF3, RF4, RF5, RF6, and RF7 are stored, for example, in a non-volatile storage device 35.

[0119] The sequence of steps related to data acquisition and storage includes the following steps: each time a total time interval with frequencies falling within the preset frequency range RF1, RF2, RF3, RF4, RF5, RF6, RF7 is measured, the occurrence count of the corresponding frequency range RF1, RF2, RF3, RF4, RF5, RF6, RF7 for the total time interval ΔT is increased by 1.

[0120] That is, whenever a total time interval with frequencies falling within a preset frequency range is measured, the corresponding preset frequency range RF1, RF2, RF3, RF4, RF5, RF6, and RF7 are activated until the total number increases by 1, that is, the number of occurrences increases by 1.

[0121] In detail, an electronic control and command unit can be provided to compare the frequency value of the measured total time interval with the range of a preset frequency range, and when there is a correspondence between the measured value and the range stored in the memory, the count will be increased by 1.

[0122] It is worth noting that the occurrence count means the number of times a given event repeats over time. For example, if during the measurement period, a heat-absorbing motor at a frequency of 30 Hz is sensed 100 times, a heat-absorbing motor at a frequency of 31 Hz is sensed 100 times, a heat-absorbing motor at a frequency of 32 Hz is sensed 100 times, a heat-absorbing motor at a frequency of 33 Hz is sensed 100 times, and a heat-absorbing motor at a frequency of 34 Hz ​​is sensed 100 times, then the number of occurrences of the preset frequency range RF2 from 30 Hz to 34 Hz ​​is 500 times.

[0123] Figure 3A graph of occurrence counts created using the method described herein is shown, where the Y-axis represents the occurrence count, denoted by N (the occurrence count has no unit of measurement), and the X-axis represents the frequency (Hertz), showing the preset frequency ranges RF1, RF2, RF3, RF4, RF5, RF6, and RF7. This graph of occurrence counts illustrates a portion of the method and can be created and displayed during the method to check its correct operation. However, creating and / or displaying this graph of occurrence counts is not necessary for the correct operation of the method.

[0124] If the acquisition device has both volatile and non-volatile memory, the sequence of steps related to acquiring and storing data may include the following steps: storing the occurrence counts within a corresponding frequency range in the volatile memory until a predetermined maximum value is reached; when the predetermined maximum value is reached, storing the occurrence counts in the non-volatile memory. Alternatively, during data transfer from one memory to another, the occurrence counts stored in the non-volatile memory may be one for each maximum occurrence count reached in the volatile memory.

[0125] As an example, if the sampling period is equal to 250 ms, the calibration step could offer the option of setting a predetermined maximum value of 240, such that reaching this maximum value corresponds to the motor running for one minute within a preset frequency range. In this way, for example, the count in the non-volatile memory could be increased by 1 for every occurrence of 240 within the same range of measured frequencies stored in the volatile memory. This means storing one minute of the motor running at a predetermined speed in the non-volatile memory. It is important to note that this is not a continuous minute within the preset rotational frequency range, but rather indicates that the motor runs for one minute as a whole within a given range of rotational frequencies during use.

[0126] The method can also provide the ability to store the measured data in non-volatile memory in the case of sensing the inactivity of the heat-absorbing motor after sensing its activity, including in the case where a predetermined maximum number of occurrences has not been reached.

[0127] The sequence of steps related to data acquisition and storage ends when the number of occurrences within a preset frequency range is reached. Therefore, the operation performed by the acquisition device 15 concludes.

[0128] Specifically, this step ends after measuring the total number of at least one predetermined time interval ΔT.

[0129] At this point, the method provides a step of transmitting the numerical values ​​of the number of occurrences within a preset frequency range from the acquisition device 15 to the remote device 55, which may then send them to another remote device 70, for example.

[0130] The transmission of measured and stored data can be performed automatically, for example, by bringing a remote device close to the acquisition device until the corresponding transceiver devices 40, 65 establish communication between the remote device and the acquisition device.

[0131] The sequence of steps related to processing the acquired data begins with the following steps: comparing the number of occurrences of each preset frequency range RF1, RF2, RF3, RF4, RF5, RF6, RF7 of the measured total time interval, and identifying the two preset frequency ranges with the maximum number of occurrences, marking the one with the lowest frequency (i.e., the lower frequency) among these two preset frequency ranges to indicate the rotational frequency range of minimum speed, and marking the other (i.e., the one with the highest frequency between the two) to indicate the rotational frequency range of maximum speed.

[0132] Specifically, a preset frequency range is provided for selection, which has a maximum frequency of occurrence and a smaller frequency relative to a preset frequency value indicating an intermediate rotational speed, and indicates that the preset frequency range indicates a rotational frequency range with minimum speed.

[0133] As an example, these two ranges are in Figure 3 The preset frequency ranges are MIN (RF2, from 30 Hz to 35 Hz) and MAX (RF7, from 55 Hz to 60 Hz), respectively.

[0134] Then, the total threshold frequency is calculated by calculating the arithmetic mean between a frequency in the range of minimum speed and a frequency in the range of maximum speed. For example, to calculate this total threshold frequency, the lowest end of a preset frequency range indicating that the motor rotates at minimum speed and the highest end of a preset frequency range indicating that the motor rotates at maximum speed can be used.

[0135] Then, multiple correction coefficients can be determined by dividing the number of peaks in the peak sequence by 1 and by each of the positive integers that are least common multiples of the number of peaks. Specifically, after determining the positive integers that are least common multiples of the number of peaks, a first correction coefficient is obtained by dividing the number of peaks in the peak sequence by 1, a second correction coefficient is obtained by dividing the number of peaks by a positive integer that is a least common multiple of the number of peaks, a third correction coefficient is obtained by dividing the number of peaks by another positive integer that is a least common multiple of the number of peaks, and so on. Obviously, calculating the correction coefficient by dividing the number of peaks by the same number is excluded, because the correction coefficient would be equal to 1, and therefore it would not be a correction coefficient.

[0136] In the embodiment showing 6 peaks, 6, 3, and 2 are obtained as correction coefficients by dividing 6 by 1, 2, and 3. Correction coefficient 6 is applied to the case where each measured peak in the peak sequence of 6 peaks is due to a magnetic field change caused by arcing. Correction coefficient 3 is applied to the case where only 3 of the 6 peaks are due to magnetic field changes caused by arcing, because an electromagnetic field change of another nature (specifically, an electromagnetic field change due to the rotation of a free wheel) is inserted between every two magnetic field changes caused by arcing. Correction coefficient 2 is applied to the case where two of the 6 peaks are due to magnetic field changes caused by arcing, because two electromagnetic field changes of another nature are inserted between every two magnetic field changes caused by arcing.

[0137] The sequence of steps related to processing the acquired data continues to calculate multiple rotational frequencies by multiplying each of the multiple correction coefficients by the frequency value of the minimum speed frequency range (preferably the lowest end of the minimum speed frequency range).

[0138] The calculated rotational frequency value is then compared to a (preset) reference frequency range that indicates the idle speed of the heat-absorbing motor. For example, this reference frequency range for indicating the idle speed of the heat-absorbing motor includes frequencies corresponding to the motor operating between a minimum of 2200 rpm and a maximum of 4000 rpm.

[0139] Typically, all engines used in the tool have an idle speed that is included in that range.

[0140] The reference frequency range for indicating idling speed can be stored, for example, in the non-volatile memory of a remote device or another remote device.

[0141] The sequence of steps related to processing the acquired data continues by storing the correction coefficients, among the plurality of correction coefficients, corresponding to the rotational frequencies falling within the reference frequency range indicating the idling speed of the heat-absorbing motor, as low-speed correction coefficients, and calculating the representative rotational frequency for each preset frequency range below a threshold frequency by multiplying the frequency value of each range by the low-speed correction coefficient. Preferably, the frequency value used to multiply by the low-speed correction coefficient for each preset frequency range is the lowest end of that range.

[0142] Then, depending on which of the remote devices, the remote device and the other remote device, processes the data, the calculated representative rotation frequency is stored in, for example, the non-volatile memory of the remote device or the other remote device.

[0143] The sequence of steps related to processing the acquired data continues to calculate multiple rotational frequencies by multiplying each of the multiple correction coefficients by the frequency value of the frequency range of the maximum speed, preferably by multiplying by the highest end of the frequency range of the maximum speed.

[0144] Then, the calculated rotational frequency value is compared with the (preset) reference frequency range that indicates the maximum operating frequency of the heat absorption motor.

[0145] For example, to improve accuracy, the method may provide a database that makes available a variety of types of tools with heat-absorbing motors (including, for example, those listed above), wherein each type of tool is associated with a predetermined reference frequency range indicating the maximum operating range of the heat-absorbing motor for that type of tool. Thus, a comparison step is provided that allows selection of a type of tool from the database of multiple types of tools, and a reference frequency range indicating the maximum operating range of the heat-absorbing motor associated with the selected type of tool, to perform a comparison between the calculated value of the rotational frequency and the reference frequency range indicating the maximum operating range of the heat-absorbing motor.

[0146] This method can also provide such a prediction for the reference frequency value of the minimum speed.

[0147] The reference frequency range indicating the maximum operating frequency can be stored, for example, in the non-volatile memory of a remote device or another remote device.

[0148] The sequence of steps related to processing the acquired data continues by storing a plurality of correction coefficients, among those corresponding to rotational frequencies falling within the reference frequency range indicating the maximum operating frequency of the heat-absorbing motor, as high-speed correction coefficients. A representative rotational frequency for each preset frequency range above a threshold frequency is calculated by multiplying the frequency value of each preset frequency range by the high-speed correction coefficient. Preferably, the frequency value used to multiply by the high-speed correction coefficient for each preset frequency range is the highest end of that range.

[0149] The calculated representative rotation frequency is then preferably stored in the non-volatile memory of a remote device or another remote device.

[0150] Then, by multiplying the number of occurrences of each frequency range by the value of the preset sampling period ΔC, and relating it to the running time calculated in the corresponding preset frequency range in the sense of connection until a bidirectional single connection exists, the running time of the motor having been running at the rotational frequency of each preset frequency range is determined.

[0151] If both volatile and non-volatile memory exist, the count of occurrences stored in the non-volatile memory is used, so the count of occurrences already represents the number of minutes the motor has been running.

[0152] This method can then provide a conversion of the calculated representative rotational frequency value into revolutions per minute, or rpm. This conversion of the unit of measurement is achieved by multiplying the frequency value (Hertz) by 60.

[0153] The method may also provide the step of displaying the report on the display device 85 (e.g.) Figure 4 As shown), the report indicates the associated running time for each calculated representative rotational frequency value, preferably displayed in revolutions per minute.

[0154] As an alternative to or additional to this display step, the method may provide a comparison of a running time value associated with a preselected value of a representative rotational frequency with a predetermined threshold of running time at a given rotational speed, and generate an alarm signal if the threshold is exceeded. For example, the method may provide a comparison of a running time value of a representative frequency value corresponding to a preset frequency range of maximum speed with a preset threshold of running time of the motor at maximum speed.

[0155] Although a method has been described in which the frequency is obtained from the total time interval and the consecutive steps provide the frequency for processing the calculation, the method in which the frequency is not obtained and the consecutive steps are a function of the time interval is completely equivalent. Note the analysis of the number of occurrences of the measured values, while taking into account that the bar indicating the maximum rotational speed is now at a value lower than the average value between the two maximum bars (which is the value of the time interval), while the bar indicating the idle rotational speed now has a larger value relative to the average value between the two maximum bars.

[0156] In an embodiment not shown, the portion of the method up to the part relating the running time to a predetermined rotational speed is not excluded from being performed solely by the acquisition device. Here, the remote device only performs the step of displaying the acquired data, i.e., the step of creating a report of that data. This embodiment loses the advantage of reduced battery consumption of the acquisition device 15 when the acquisition device 15 is not assigned to process the data, and also loses the advantage of the acquisition device being particularly simple, and therefore robust and affordable; however, it allows the advantages associated with the features of claim 1 to be obtained in any case.

[0157] The device according to the method of the invention operates as follows. The user mounts the acquisition device 15 onto the protective crankcase 10 of the tool, for example, by adhesive or a non-removable or removable connecting member. Then, during the operation of the tool's heat-absorbing motor, the acquisition device stores data that will be forcibly processed by a remote device 55 or another remote device 70. In particular, once the use of the tool is finished, the user can bring the remote device 55 close to the acquisition device 15 to establish wireless communication between the two, for example, to allow the acquisition data to be transmitted to the remote device. Depending on this configuration, the acquired data can be processed directly by the remote device or sent to another remote device for processing. If the data is sent to another remote device 70, the acquired data is simultaneously stored in the remote device 55 until a connection can be established between the remote device and the other remote device. Once the data has been processed to obtain the running time at a representative rotational speed, the data is displayed on a display device (e.g., as shown in...). Figure 4 (The form of the report).

[0158] The present invention, conceived in this way, is susceptible to many modifications and variations, all of which fall within the same inventive concept.

[0159] Furthermore, all the details can be replaced by other technically equivalent components.

[0160] In practice, any material and any possible shape and size may be used as needed without departing from the scope of protection of the appended claims.

Claims

1. A method for estimating the time for a heat-absorbing motor of a tool (5) to operate at a predetermined rotational speed by means of a measurement performed by a sensing sensor (25), comprising the steps of: - The total time interval (ΔT) is measured cyclically within a preset sampling period (ΔC) by initiating the measurement of the total time interval (ΔT) when the first peak change of the electromagnetic field is sensed and terminating the measurement of the total time interval when the last peak change of the electromagnetic field is sensed, wherein the first peak and the last peak are the start and end of a peak sequence having a predetermined number of consecutive peaks, the number of peaks being at least equal to 6 and being a positive integer that is at least a least common multiple of 2 and 3. -The respective frequencies are obtained from the measured total time interval (ΔT). - Make multiple preset frequency ranges (RF1, RF2, RF3, RF4, RF5, RF6, RF7) available for the measured total time interval. - Each time the total time interval (ΔT) of frequencies falling within each of the plurality of preset frequency ranges (RF1, RF2, RF3, RF4, RF5, RF6, RF7) is measured, the count of occurrence of the preset frequency range is increased by 1. - Select two preset frequency ranges (RF1, RF2, RF3, RF4, RF5, RF6, RF7) that have the maximum number of occurrences. The preset frequency range with the lowest frequency represents the preset frequency range with the minimum speed, and the preset frequency range with the highest frequency represents the preset frequency range with the maximum speed. - The total threshold frequency is calculated by taking the arithmetic mean between a frequency within the frequency range of at least the minimum speed and a frequency within the frequency range of the maximum speed. - Determine multiple correction coefficients, each obtained by dividing the number of peaks in the peak sequence by 1 and by each of the positive integers whose least common multiple is the number of peaks. - Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the frequency range of the minimum speed. - Compare the calculated value of the rotational frequency with a preset reference frequency range that indicates the idle speed of the heat-absorbing motor. - Store the correction coefficients among the plurality of correction coefficients that correspond to the rotational frequency falling within the reference frequency range indicating the idle speed of the heat-absorbing motor as low-speed correction coefficients. - The representative rotational frequency for each preset frequency range below the total threshold frequency is calculated by multiplying the frequency value of each range by the correction factor for the low speed. - Store the calculated representative rotation frequency. - Multiple rotational frequencies are calculated by multiplying each of the multiple correction factors by the frequency value of the frequency range of the maximum speed. - Compare the calculated value of the rotational frequency with a reference frequency range that indicates the maximum operating range of the heat-absorbing motor. - Store the correction coefficients corresponding to the rotational frequencies falling within the preset frequency range indicating the maximum operation of the heat-absorbing motor as high-speed correction coefficients. - The representative rotational frequency for each preset frequency range greater than the total threshold frequency is calculated by multiplying the frequency value for each range greater than the total threshold frequency by the high-speed correction factor. - Store the calculated representative rotation frequency, and - The running time during which the motor has been running at the rotational frequency of each preset frequency range is determined by multiplying the number of occurrences of each preset frequency range by the value of the preset sampling period (ΔC). - A report is displayed on the display device, indicating the associated running time for each calculated representative rotation frequency value.

2. The method according to claim 1, further comprising the following step: - Make a database of various types of tools equipped with heat-absorbing motors available, wherein each type of tool is associated with a reference frequency range indicating the maximum operating frequency of the heat-absorbing motor for that type of tool. - Allows selection of one type of tool from the database of the various types of tools, and - Use a reference frequency range indicating the maximum operating frequency of the heat-absorbing motor associated with the selected type of tool to perform a comparison between the calculated value of the rotational frequency and the preset frequency range indicating the maximum operating frequency of the heat-absorbing motor.

3. The method of claim 1, wherein the step of measuring the total number of at least one predetermined time interval (ΔC) includes the step of accelerating the heat-absorbing motor of the tool (5) from idle speed to maximum speed at least once.

4. A device (1) for a heat-absorbing motor of a delay estimation tool (5) to operate at a predetermined rotational speed for a period of time, the device comprising a data acquisition device (15) provided with: -Inductive sensor (25), - Storage units (30, 35), - Wireless transmitter (40), - Power supply battery (50), and - An electronic control and command unit (45), operably connected to the sensing sensor, the wireless transmitter, and the storage unit, and configured to: The total time interval is measured cyclically within a preset sampling period by initiating the measurement of the total time interval when the first peak of the electromagnetic field is sensed and terminating the measurement of the total time interval when the last peak of the electromagnetic field is sensed. The first peak and the last peak are the start and end points of a peak sequence having a predetermined number of consecutive peaks, the number of peaks being at least equal to 6 and a positive integer that is at least a least common multiple of 1, 2, and 3. o Obtain their respective frequencies from the total measured time intervals. o provides multiple preset frequency ranges for the measured total time interval, Each time a total time interval with the stated frequency is measured, the count of occurrences of the corresponding frequency range is increased by 1. The device (1) further includes a remote device (55), the remote device (55) having: - Wireless receiver (65), - A processing unit (60), operably connected to the wireless receiver, and configured to perform the steps of the method according to claim 1, the steps being: selecting two preset frequency ranges with the maximum number of occurrences from the plurality of preset frequency ranges (RF1, RF2, RF3, RF4, RF5, RF6, RF7), wherein the preset frequency range with the lowest frequency among the preset frequency ranges with the maximum number of occurrences represents the preset frequency range with the minimum speed, and the preset frequency range with the highest frequency represents the preset frequency range with the maximum speed, up to the last step of the method.

5. The device (1) according to claim 4, wherein, The remote device (55) includes a display device (85), wherein the processing unit (60) is configured to display a report on the display device, the report showing the associated running time for each calculated representative rotation frequency value.

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