Patent Publication Number: US-2021173378-A1

Title: Power tool element indicating system and method

Description:
FIELD OF THE INVENTION 
     The present invention relates to power tool element indicating systems and methods and power tools comprising such systems and methods. 
     BACKGROUND TO THE INVENTION 
     Power tools, gardening tools and the like often have a replaceable and/or adjustable element. For example, many power tools and gardening tools have one or more replaceable elements in the form of a rotating or reciprocating blade that is worn down or blunted over time through use. Once the blade no longer cuts effectively, the blade needs to be replaced. However, one problem associated with such replaceable blades is the user being unaware that the blade needs to be replaced. For example, some power tools still perform their function, albeit less effectively and/or less efficiently, even though the blade needs to be replaced. In other examples, such as with some rotary or cylindrical lawn mowers, the blade is not visible to the user during ordinary use of the power tool such that the user is not aware that the blade needs to be replaced. 
     Many power tools and gardening tools have an adjustable element, the position of which can be adjusted according to different requirements, such as the type of power tool, a particular application and/or an extent of use of the element. For example, a chain of a chainsaw is one form of an adjustable element, which is also a replaceable element. The tension of a chainsaw chain typically reduces through use and often needs to be adjusted to increase the tension of the chain. If the chain becomes too loose, the cutting efficiency and effectiveness of the chain is impaired and in some cases, the chain can detach from the guide bar of the chainsaw. 
     For some power tools and gardening tools, it is possible to install a replaceable and/or adjustable element incorrectly, yet the tool can still operate and seem to perform its function. For example, for at least some chainsaws, it possible, and quite easy, to install the chain backwards on the guide bar. The chainsaw will still operate and seem to work to the user, but the blades are facing in the wrong direction and so do not cut properly, which can damage the chain and the chainsaw. 
     For other power tools and gardening tools, it is necessary for certain types of replaceable and/or adjustable elements to have a particular clearance to allow for, for example, adequate airflow. In other examples, multiple positions for a replaceable and/or adjustable element are possible in a single tool, but the correct positions are not apparent to the user and/or which position achieves which effect. 
     SUMMARY OF THE INVENTION 
     It is a preferred object of the present invention to provide a system and/or a method that addresses, or at least ameliorates, one or more of the aforementioned problems and/or provides a useful commercial alternative. 
     According to one aspect, but not necessarily the broadest aspect, the present invention resides in a power tool element indicating system comprising: 
     a detection device in communication with a replaceable and/or adjustable element of a power tool to determine whether the replaceable and/or adjustable element of the power tool requires replacement or adjustment; and 
     an indicator in communication with the detection device to indicate that the replaceable and/or adjustable element requires replacement or adjustment. 
     Preferably, the detection device is configured to record operation of the replaceable and/or adjustable element, compare the recorded operation with a threshold value and determine that the replaceable and/or adjustable element requires replacement or adjustment when the recorded operation equals or exceeds the threshold value. 
     Suitably, the detection device is configured to record one or more of the following operations of the replaceable and/or adjustable element: a cumulative duration of use; a number of rotations; a rate of rotation; a number of oscillations; a number of reciprocations; a number of cycles; a number of movements. 
     Preferably, the detection device is configured to determine a position and/or orientation and/or other characteristic of the replaceable and/or adjustable element, compare the determined position and/or orientation and/or other characteristic with a threshold value or a range and determine that the replaceable and/or adjustable element requires replacement or adjustment when the determined position and/or orientation and/or other characteristic does not comply with the threshold value or the range. 
     Suitably, the detection device is configured to determine one or more of the following of the replaceable and/or adjustable element: a level of wear; a wear profile; an electric current profile; a separation from a part of the power tool; a level of protrusion; an installation orientation; a level of tension. 
     Suitably, the detection device analyses a determined characteristic of the replaceable and/or adjustable element, such as, but not limited to, the level of wear, and/or the wear profile, to determine an estimated remaining lifespan of the replaceable and/or adjustable element. 
     Suitably, the detection device disables operation of the power tool if the detection device determines that the replaceable and/or adjustable element requires replacement or adjustment. 
     Preferably, the detection device resets or deletes the recorded operation of the replaceable element when the detection device determines that the replaceable element has been replaced. 
     Preferably, the detection device resets the indicator when the detection device determines that the replaceable and/or adjustable element has been replaced or adjusted. 
     Suitably, the detection device determines whether the replaceable and/or adjustable element is compatible with the power tool. 
     Suitably, the indicator comprises one or more of the following: an illumination device; an LED; a display; a liquid crystal display (LCD); a touch sensitive display; an audible indicator. 
     Suitably, the indicator is part of a user&#39;s computing device, such as a mobile phone, tablet or computer. 
     Suitably, the detection device comprises a wireless reader mounted on, in or to the power tool, the wireless reader in communication with a wireless transmitter attached to, embedded in, or part of the replaceable and/or adjustable element. 
     According to another aspect, but not necessarily the broadest aspect, the present invention resides in a power tool element indicating method comprising: 
     determining, by a detection device in communication with a replaceable and/or adjustable element of a power tool, whether the replaceable and/or adjustable element of the power tool requires replacement or adjustment; and 
     indicating, by an indicator in communication with the detection device, that the replaceable and/or adjustable element requires replacement or adjustment. 
     The method may comprise the detection device: 
     recording operation of the replaceable and/or adjustable element; 
     comparing the recorded operation with a threshold value; and 
     determining that the replaceable and/or adjustable element requires replacement or adjustment when the recorded operation equals or exceeds the threshold value. 
     The method may comprise the detection device recording one or more of the following operations of the replaceable and/or adjustable element: a cumulative duration of use; a number of rotations; a rate of rotation; a number of oscillations; a number of reciprocations; a number of cycles; a number of movements. 
     The method may comprise the detection device: 
     determining a position and/or orientation and/or other characteristic of the replaceable and/or adjustable element; 
     comparing the determined position and/or orientation and/or other characteristic with a threshold value or a range; and 
     determining that the replaceable and/or adjustable element requires replacement or adjustment when the determined position and/or orientation and/or other characteristic does not comply with the threshold value or the range. 
     The method may comprise the detection device determining one or more of the following of the replaceable and/or adjustable element: a level of wear; a wear profile; an electric current profile; a separation from a part of the power tool; a level of protrusion; an installation orientation; a level of tension. 
     The method may comprise the detection device analyzing a determined characteristic of the replaceable and/or adjustable element and determining an estimated remaining lifespan of the replaceable and/or adjustable element. 
     The method may comprise the detection device disabling operation of the power tool if the detection device determines that the replaceable and/or adjustable element requires replacement or adjustment. 
     The method may comprise the detection device resetting or deleting the recorded operation of the replaceable element when the detection device determines that the replaceable element has been replaced. 
     The method may comprise the detection device resetting the indicator when the detection device determines that the replaceable and/or adjustable element has been replaced or adjusted. 
     The method may comprise the detection device determining whether the replaceable and/or adjustable element is compatible with the power tool. 
     According to another aspect, but not necessarily the broadest aspect, the present invention resides in a power tool element indicating system comprising a detection device in communication with a replaceable and/or adjustable element of a power tool to: 
     determine one or more characteristics of the replaceable and/or adjustable element; and 
     analyze the one or more characteristics to determine an estimated remaining lifespan of the replaceable and/or adjustable element. 
     Preferably, the system comprises an indicator in communication with the detection device to display the estimated remaining lifespan of the replaceable and/or adjustable element. 
     Preferably, the detection device is configured to perform one or more of the aforementioned operations. 
     According to another aspect, but not necessarily the broadest aspect, the present invention resides in a power tool comprising the aforementioned power tool element indicating system. 
     Suitably, the power tool is selected from one of the following: a lawn mower; a lawn edger; a circular saw; a jigsaw; a reciprocating saw; a mulcher; a chipper; a chainsaw; a pole pruner; a drill; a power file; a sander; a belt sander; an orbital sander; a grinder; a hedge trimmer; a stapler; a sweeper; a router; a nail gun; or other power tool. 
     Suitably, the replaceable and/or adjustable element is selected from one of the following: a blade; a catching blade; a cutting blade; a mulching blade; a hybrid blade; a chainsaw chain; an abrading element; a brush; a drill chuck; a carriage; a carrier, or other element. 
     Further features and/or aspects of the present invention will become apparent from the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which like reference numerals refer to like features. In the drawings: 
         FIG. 1  is a schematic diagram of a power tool element indicating system according to an embodiment of the present invention; 
         FIG. 2  is a schematic diagram of part of a power tool element indicating system according to an embodiment of the present invention; 
         FIG. 3  is a general flow diagram illustrating a power tool element indicating method according to an embodiment of the present invention; 
         FIG. 4  is a general flow diagram illustrating a power tool element indicating method according to another embodiment of the present invention; 
         FIG. 5  is a general flow diagram illustrating a power tool element indicating method according to a further embodiment of the present invention; 
         FIG. 6  is a general flow diagram illustrating a power tool element indicating method according to a yet further embodiment of the present invention; and 
         FIG. 7  is a general flow diagram illustrating a power tool element indicating method according to another embodiment of the present invention. 
     
    
    
     Skilled addressees will appreciate that elements in the drawings are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the relative dimensions of some of the elements in the drawings may be distorted and/or some elements may be omitted to help improve understanding of embodiments of the present invention. 
     DETAILED DESCRIPTION 
     Embodiments of the present invention are directed to power tool element indicating systems and methods and power tools comprising such systems. Herein, the term “power tool” refers to any power tool, gardening tool or the like for domestic, commercial or industrial use comprising an element, such as a blade, a chain or other element that is replaceable and/or adjustable. The power tool can be electrically operated by an alternating current (AC) or direct current (DC) power supply. However, it is envisaged that the present invention can also be used with tools comprising a power supply in the form of an internal combustion (IC) engine, such as a 2-stroke or 4-stroke engine and having an electric circuit for the present invention. 
     With reference to  FIG. 1 , according to some embodiments, the present invention is a power tool element indicating system  100  comprising a detection device  102  in communication with a replaceable and/or adjustable element  104  of a power tool  106  to determine that the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment. The power tool element indicating system  100  comprises an indicator  108  in communication with the detection device  102  to indicate that the replaceable and/or adjustable element  104  requires replacement or adjustment. 
     According to some embodiments, the detection device  102  is configured to detect and record operation of the replaceable and/or adjustable element  104 , compare the recorded operation with a threshold value and determine that the replaceable and/or adjustable element  104  requires replacement or adjustment when the recorded operation equals or exceeds the threshold value. For example, the detection device  102  can detect and record for how much time the replaceable and/or adjustable element  104  has been in use and compare the recorded usage time with a threshold time value. When the cumulative recorded usage equals or exceeds the threshold time value, the detection device  102  transmits a signal to the indicator  108  and the indicator  108  indicates that the replaceable and/or adjustable element  104  requires replacement or adjustment. In some instances, the element  104  will need replacing when the threshold time value is reached or exceeded. In some instances, when the threshold time value is reached or exceeded, the element  104  will require adjustment, for example, changing a mounting position of the element  104  to compensate for a level of wear in the element  104  after the threshold time value of use. 
     Different power tools will have different modes of operation. For example, lawn mowers, lawn edgers, circular saws, mulchers and many other power tools have rotating elements in the form of blades, such as cutting blades, catching blades, hybrid blades or mulching blades. Other power tools, such as jigsaws and reciprocating saws, have reciprocating elements in the form of sawtooth blades. Other power tools have continuous cutting or abrading elements, such as the chains of chainsaws and pole pruners, which move along a guide bar, or abrasive belts as used in power files or belt sanders. Other tools have replaceable/adjustable elements in the form of brushes, drill chucks, or carriages or carriers for loading a consumable, such as fasteners, e.g. as used in a nail gun. 
     According to some embodiments of the present invention, the detection device  102  is configured to record one or more of the following operations of the replaceable and/or adjustable element  104 : a cumulative duration of use; a number of rotations; a rate of rotation, i.e., revolutions per minute (RPM) or other rate measurement; a number of oscillations; a number of reciprocations; a number of cycles; a number of movements. 
     Consequently, according to some embodiments, the detection device  102  is configured to detect and record the relevant operation of the replaceable and/or adjustable element  104 , compare the recorded operation with a threshold value for the relevant operation and determine that the replaceable and/or adjustable element  104  requires replacement or adjustment when the recorded relevant operation equals or exceeds the threshold value for that operation. 
     According to some embodiments, the detection device  102  is configured to determine a position and/or an orientation and/or other characteristic of the replaceable and/or adjustable element  104 . The detection device  102  is configured to compare the determined position and/or orientation and/or other characteristic of the replaceable and/or adjustable element  104  with a threshold value or a range for the position and/or orientation and/or other characteristic. The detection device  102  is configured to determine that the replaceable and/or adjustable element  104  requires adjustment when the determined position and/or orientation and/or other characteristic of the replaceable and/or adjustable element  104  does not comply with the threshold value or the range. 
     In particular, the detection device  102  is configured to determine one or more of the following of the replaceable and/or adjustable element  104 : a level of wear; a profile; a separation from a part of the power tool  106 ; a level of protrusion; an installation orientation; a level of tension. 
     For example, in relation to a chain of a chainsaw, in some embodiments, the detection device  102  can determine whether the chain is installed on the guide bar in the correct orientation, i.e. in a forward, cutting direction, and not installed backwards. In some embodiments, the detection device  102  can determine whether the tension of the chain is sufficient. In another example, according to some embodiments of the present invention, the detection device  102  can determine whether the replaceable and/or adjustable element  104  has the required separation or clearance from, for example, a body, cage, guard or cover of the power tool  106 , to ensure that, for example, the replaceable and/or adjustable element  104  does not catch on the body, cage, guard or cover of the power tool  106  and/or provides adequate airflow. In other examples, according to some embodiments of the present invention, the detection device  102  can determine a level of wear of the replaceable and/or adjustable element  104  such that when the element  104  has been worn down through use below a threshold level, such as, but not limited to 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% of the original, unused level, the detection device  102  transmits a signal to the indicator  108  to indicate that the replaceable and/or adjustable element  104  needs replacing or adjusting. Whether the indicator  108  indicates replacement or adjustment will depend on the level of wear. A lower level of wear will likely result in an indication by the indicator  108  that the element  104  can be adjusted and does not need to be replaced. A higher level of wear may result in an indication by the indicator  108  that the element  104  needs to be replaced. In some instances, although the replaceable and/or adjustable element  104  may not have been used for a cumulatively long period of time and show low levels of wear, a high impact event, such as a collision of the element  104  with a rock or other hard object can be detected by the detection device  102 , for example, by analyzing the resultant profile of the element  104 . Such a collision may deform the profile of the element  104 , rendering the element inoperable, inefficient or ineffective in its intended operation, such that the element  104  needs to be replaced. 
     According to some embodiments, the detection device  104  analyses a determined characteristic of the replaceable and/or adjustable element  104 , such as, but not limited to, the level of wear, and/or the profile of the element  104 , to determine an estimated remaining lifespan of the replaceable and/or adjustable element  104 . For example, if the replaceable and/or adjustable element  104  is expected to have a lifespan of  6  months based on x rotations of the element  104  or y hours of use, if the detection device  104  determines that the element  104  has undergone x/2 rotations or been used for x/2 hours, the detection device  104  determine can determine that the remaining lifespan of the replaceable and/or adjustable element  104  is approximately 3 months. 
     According to some embodiments of the present invention, the detection device  102  disables operation of the power tool  106  if the detection device  102  determines that the replaceable and/or adjustable element  104  requires replacement or adjustment. This can prevent, for example, damage to the power tool  106  and/or ineffective or inefficient operation and/or potential damage to the environment being worked upon and/or potential hazard to the user. 
     According to some embodiments, the detection device  102  resets or deletes the recorded operation of the replaceable element  104  when the detection device  102  determines that the replaceable element  104  has been replaced. The detection device  102  can then record new data for the newly replaced element  104 . 
     According to some embodiments, the detection device  102  resets the indicator  108  when the detection device  102  determines that the replaceable and/or adjustable element  104  has been replaced or adjusted. The indicator  108  is therefore ready to display information pertinent to the newly replaced element  104 . 
     According to some embodiments of the present invention, the detection device  102  determines whether the replaceable and/or adjustable element  104  is compatible with the power tool  106 . For example, common fittings may be used for different types of element  104  suitable for different types of power tool. In some embodiments, the detection device  102  can determine whether the replaceable and/or adjustable element  104  is appropriate, suitable for, and/or compatible with the power tool  106  to which it is attached and display an appropriate indication via the indicator  108 . 
     According to some embodiments, the indicator  108  comprises one or more of the following: an illumination device, such as, but not limited to a light emitting diode (LED); a display, such as a liquid crystal display (LCD) or a touch sensitive display; an audible indicator. For example, in some embodiments, under the relevant conditions as described herein, the detection device  102  causes the indicator  108  in the form of an LED to illuminate to indicate to a user that the replaceable and/or adjustable element  104  needs to be replaced or adjusted. In some embodiments, the LED or other illumination device can emit a first colour to indicate that the element  104  needs to be replaced and can emit a second colour to indicate that the element needs to be adjusted. In other embodiments, where the indicator  108  is in the form of a display, the display can display one or more icons or other indicators to indicate to a user that the element  104  needs to be replaced or adjusted or to indicate another characteristic of the element  104 , such as an impact event, a wear profile or other event that requires inspection of the element  104  by the user. 
     In some embodiments, where the display is a touch sensitive display, the display can receive inputs from a user to indicate that, for example, the element  104  has been replaced or adjusted or to reset the indicator  108 . 
     In some embodiments, where the indicator  108  is in the form of a display, the display can be the display of user&#39;s device  112 , such as a mobile phone, tablet or other computing device, rather than, or in addition to a display provided on, or part of, the power tool  106 . In such embodiments, the detection device  102  can communicate with the user&#39;s device  112 , such as a mobile phone, tablet or other computing device, via a transceiver  110  in communication with the detection device  102 . According to different embodiments, the transceiver  110  can be capable of using one or more communication protocols, such as, but not limited to, Bluetooth, WiFi, near field communication (NFC), 3G, 4G or 5G, to enable the detection device  102  of the system  100  to communicate with the user&#39;s device  112 . In such embodiments, the user can interact with the system  100  via the user&#39;s device  112  to indicate that, for example, the element  104  has been replaced or adjusted or to reset the indicator  108 . 
     According to some embodiments, and with reference to  FIG. 2 , the detection device  102  comprises a wireless reader  120 , such as a radio frequency identification (RFID) reader  120  mounted on, to or in the power tool  106 . In such embodiments, the RFID reader  120  is in communication with a wireless transmitter  122 , such as an RFID chip  122  attached to, mounted to or associated with the replaceable and/or adjustable element  104 . The RFID reader  120  receives data from the RFID chip  122  to enable the detection device  102  to detect and record operational data relating to the replaceable and/or adjustable element  104  as described herein to enable the detection device  102  to make the determinations as described herein regarding whether the replaceable and/or adjustable element  104  needs to be replaced or adjusted. In such embodiments, when the element  104  is replaced, the RFID reader  120  reads the new RFID of the replacement element  104  and resets or deletes the recorded operation for the element  104  and resets the indicator  108 . 
     According to other embodiments, the detection device  102  comprises another type of wireless reader  120  mounted on, to or in the power tool  106  capable of communication with another type of transmitter  122  attached to, mounted to or associated with the replaceable and/or adjustable element  104  according to another communications protocol, such as Bluetooth, WiFi, or near field communication (NFC). 
     It will be appreciated that the particular implementation of the present invention and the extent of functionality can depend on the particular power tool  106  and the nature of the replaceable and/or adjustable element  104 . For example, where the power tool  106  is a mower and the replaceable and/or adjustable element  104  is a mower blade, the RFID chip  122 , or other type of device, can be embedded in, or mounted to the mower blade and the RFID reader  120 , or other type of reader of the detection device  102  can be embedded in, or mounted to a body of the mower. In such embodiments, the detection device  102 , via the chip  122  and the reader  120 , can detect, for example, a number of hours of cumulative use and compare to a threshold value of a number of hours of use to determine when the blade should be replaced or adjusted and indicate same to a user accordingly via the indicator  108 . Additionally, or alternatively, the detection device  102  can determine a degree of wear of the mower blade and/or a wear profile of the mower blade and indicate same to a user accordingly via the indicator  108 . Additionally, or alternatively, the detection device  102  can determine an electric current profile as a result of an impact with an object, such as a rock, post, tree stump or root, or other obstacle that is likely to have damaged or otherwise compromised the replaceable and/or adjustable element  104  and/or the performance of the power tool  106 . When such an impact occurs, the element  104  is often stopped, or significantly slowed down, which creates a characteristic electric current profile than can be detected by the detection device  102 . The detection device  102  can indicate detection of the electric current profile to a user via the indicator  108  that they should inspect or replace the element  104 . Such indications can be via a particular colour of LED, or via a particular icon displayed on a display. 
     In embodiments where the power tool  106  is a chainsaw, the transmitter  122  of the detection device  102 , such as the RFID chip  122 , can be nested into or otherwise embedded in, or part of the chain drive link, and a transmitter  122  can also, or alternatively, be nested into or otherwise embedded in, or part of the guide bar of the chainsaw, both of which should be changed regularly due to use. 
     In some embodiments, the transmitter  122  of the detection device  102  can communicate a characteristic of the replaceable and/or adjustable element  104 , such as whether the blade is a catching blade, a mulching blade, or a hybrid blade and adjust the RPM of a motor of the power tool  106  to the appropriate speed. For example, catching blades typically need a slightly higher RPM for better performance, whereas mulching blades typically need a lower RPM for better run time. 
     In some embodiments, based on transmitter  122  in the replaceable and/or adjustable element  104 , the indicator  108  of the power tool  106  can recommend operating cutting heights where the element  104  is a blade. For example, catching blades typically need approximately 35-80 mm+ heights to allow for adequate airflow, whereas mulching blades can typically operate from approximately 15-45 mm. 
     In embodiments where the power tool  106  is a chainsaw, the detection device  102  of the system  100  can inform the user via the indicator  108  if the replaceable and/or adjustable element  104  in the form of a chain is installed incorrectly, e.g. backwards. The detection device  102  of the system  100  can also, or alternatively inform the user via the indicator  108  if the chain is loose. This would happen because the transmitter  122  would be further from the reader  120 , or physically be out of range because the chain is too loose. In either situation, the system  100  can disable the power tool  106  until the problem is rectified and inform the user of the problem via the indicator  108 . 
     The skilled addressee will appreciate variations required according to the type of power tool  106  and the nature of the replaceable and/or adjustable element  104  that will nonetheless fall within the scope of the present invention as defined by the attached claims. 
     According to other aspects, embodiments of the present invention reside in a power tool element indicating method. With reference to  FIG. 3 , the method  300  comprises, at  305 , determining, by the detection device  102  in communication with the replaceable and/or adjustable element  104  of the power tool  106 , that the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment. At  310 , the method  300  comprises indicating, by the indicator  108  in communication with the detection device  102 , that the replaceable and/or adjustable element  104  requires replacement or adjustment. 
     With reference to  FIG. 4 , according to some embodiments, the step  305  of the detection device  102  determining that the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment comprises, at  315 , the detection device  102  recording operation of the replaceable and/or adjustable element  104 . As described herein, recording operation of the element  104  can comprise the detection device  102  recording one or more of the following operations of the replaceable and/or adjustable element  104 : a cumulative duration of use; a number of rotations; a rate of rotation; a number of oscillations; a number of reciprocations; a number of cycles; a number of movements. At  320 , the method  300  comprises the detection device  102  comparing the recorded operation with a threshold value. At  325 , the method comprises the detection device  102  determining that the replaceable and/or adjustable element  104  requires replacement or adjustment when the recorded operation equals or exceeds the threshold value and indicating same via the indicator  108 . If the recorded operation does not equal or exceed the threshold value, at  315 , the detection device  102  continues recording operation of the replaceable and/or adjustable element  104 . 
     According to some embodiments, two or more operations of the element  104  can be recorded by the detection device  102 . In such embodiments, the recorded values for two or more operations of the element  104  can be compared with respective thresholds. In such embodiments, one or more of the thresholds need to be equaled or exceeded for the detection device  102  to determine that the element  104  needs to be replaced or adjusted. Such determinations will depend on the operations of the element  104  being recorded and the power tool  106 . For example, where the operations of duration of use and rate of rotation are recorded for the element  104 , if the duration of use threshold is not reached or exceeded, if the rate of rotation has been, for example, constantly on a high setting, the detection device  102  may determine that the element  104  needs to be replaced or adjusted. 
     With reference to  FIG. 5 , according to some embodiments, the step  305  of the detection device  102  determining that the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment comprises, at  330 , the detection device  102  determining a position and/or orientation and/or other characteristic of the replaceable and/or adjustable element  104 . As described herein, such determination can comprise the detection device  102  determining one or more of the following of the replaceable and/or adjustable element  104 : a level of wear or a wear profile; an electric current profile, for example caused by high impacts with foreign objects, such as rocks; a separation of the element  104  from a part of the power tool, such as a body or casing; a level of protrusion of the element; an installation orientation; a level of tension. At  335 , the method comprises the detection device  102  comparing the determined position and/or orientation and/or other characteristic with a threshold value or a range. At  340 , the method comprises the detection device  102  determining that the replaceable and/or adjustable element  104  requires replacement or adjustment when the determined position and/or orientation and/or other characteristic does not comply with the threshold value or the range and indicating same via the indicator  108 . If the determined position and/or orientation and/or other characteristic does not equal or exceed the threshold value or range, at  330 , the detection device  102  continues determining the position and/or orientation and/or other characteristic of the replaceable and/or adjustable element  104 . 
     According to some embodiments, two or more of a position and/or orientation and/or other characteristic of the element  104  can be determined by the detection device  102 . In such embodiments, the recorded values for two or more of a position and/or orientation and/or other characteristic of the element  104  can be compared with respective thresholds or ranges. In such embodiments, one or more of the thresholds or ranges need to be equaled or exceeded for the detection device  102  to determine that the element  104  needs to be replaced or adjusted or inspected. Such determinations will depend on the position and/or orientation and/or other characteristic of the element  104  being recorded and the power tool  106 . For example, where a position and a wear profile are determined for the element  104 , if the position threshold or range is not exceeded, if the wear profile is such that the element can no longer be used, or will not perform its function efficiently and/or effectively, the detection device  102  can determine that the element  104  needs to be replaced. 
     With reference to  FIG. 6 , according to some embodiments, a method  400  of the present invention comprises, at  405 , the detection device  102  determining a characteristic associated with the replaceable and/or adjustable element  104 , such as an electric current profile caused by impacts of the element  104  with foreign bodies, such as rocks, posts, tree stumps or the like, that can potentially damage the element  104 . The method  400  comprises, at  410 , the detection device  102  analyzing the determined characteristic of the replaceable and/or adjustable element  104 . At  415 , the method comprises determining an estimated remaining lifespan of the replaceable and/or adjustable element  104 . The method comprises at  420 , the detection device  102  transmitting the calculated estimated remaining lifespan to the indicator  108 . For example, the estimated remaining lifespan can be displayed to the user via a display, in the form of, for example, a number of remaining hours of use or an icon. 
     With reference to the method  300  shown in  FIG. 7 , according to some embodiments, where the detection device  102  determines, at  305 , that the element  104  needs to be replaced or adjusted and, at  310 , the detection device  102  has indicated same via indicator  108 , at  345 , the method  300  can comprise the detection device  102  disabling operation of the power tool  106  until the element  104  has be suitably adjusted or replaced. 
     According to some embodiments, at  350 , the method  300  can comprise the detection device  102  resetting or deleting the recorded operation and/or determined position, orientation and/or characteristic(s) of the replaceable element  104  when the detection device  102  determines that the replaceable element  104  has been replaced. 
     According to some embodiments, at  355 , the method  300  can comprise the detection device  102  resetting the indicator  108  when the detection device  102  determines that the replaceable and/or adjustable element  104  has been replaced or adjusted. 
     According to some embodiments, at  360 , the method  300  can comprise the detection device  102  determining whether the replaceable and/or adjustable element  104  is compatible with the power tool  106 . It will be appreciated that in embodiments in which the compatibility of the element  104  is determined, this step can occur before the data relating to the previous element  104  is deleted or reset and/or before the indicator  108  is reset. 
     According to another aspect, the present invention resides in a power tool element indicating system  100  comprising the detection device  102  in communication with the replaceable and/or adjustable element  104  of the power tool  106  to determine one or more characteristics of the replaceable and/or adjustable element  104  and analyze the one or more characteristics to determine an estimated remaining lifespan of the replaceable and/or adjustable element, as described herein. The system comprises the indicator  108  in communication with the detection device  102  to display the estimated remaining lifespan of the replaceable and/or adjustable element  104 . It will be appreciated that in preferred embodiments, the detection device  102  is also configured to perform one or more of the aforementioned operations of the detection device  102  as described herein. 
     Another aspect of the present invention resides in the power tool  106  comprising the power tool element indicating systems  100  and methods  300 ,  400  as described herein. It will be appreciated that the power tool element indicating systems  100  and methods  300 ,  400  are applicable to a wide range of power tools having one or more replaceable and/or adjustable elements  104 . For example, embodiments of the present invention are applicable to power tools such as, but not limited to lawn mowers, lawn edgers, circular saws, jigsaws, reciprocating saws, mulchers, chippers, chainsaws, pole pruners, drills, power files, sanders, such as belt sanders and orbital sanders, grinders, hedge trimmers, staplers, sweepers, routers; nail guns and other tools. 
     Hence, embodiments of the present invention address, or at least ameliorate one or more of the aforementioned problems by the detection device  102  determining whether the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment and indicating to a user via the indicator  108  that the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment. The user can then adjust or replace the element  104  to ensure efficient and effective operation of the power tool and reduce the likelihood of damage to the power tool and/or the user. The present invention is particularly useful when the element  104  is not visible to the user during ordinary use of the power tool and/or where it is not readily apparent to the user that the element  104  needs replacement or adjustment. 
     Embodiments of the present invention can include recording one or more operations of the element  104 , such as duration of use, number of rotations, rate of rotation and the like, and/or one or more of a position, orientation and/or other characteristic of the element, such as a level of wear, a wear profile and/or an electric current profile to determine whether the replaceable and/or adjustable element  104  of the power tool  106  requires replacement or adjustment. Some embodiments comprise calculating an estimated remaining lifespan of the element  104  and/or determining a compatibility of the element  104  with the power tool  106 . In some embodiments, the detection device  102  can communicate with a computing device  112  of the user to inform the user that the element  104  requires adjustment or replacement and the user can communicate with the detection device  102  via their computing device  112 . 
     In this specification, the terms, “first”, “second” etc. are intended to differentiate between different features of the present invention and are not intended to limit the present invention to a particular order of implementation unless the context indicates otherwise. 
     In this specification, the terms “comprises”, “comprising” or similar terms are intended to mean a non-exclusive inclusion, such that an apparatus that comprises a list of elements does not include those elements solely but may well include other elements not listed. 
     The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge. 
     It will be appreciated that the present invention is not limited to the specific embodiments described herein. Skilled addressees will identify variations from the specific embodiments described herein that will nonetheless fall within the scope of the present invention, which is determined by the following claims.