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Title:
A POWER TOOL COMMUNICATION SYSTEM
Document Type and Number:
WIPO Patent Application WO/2019/103685
Kind Code:
A1
Abstract:
The present disclosure relates to power tool communication system (1) comprising a hand-held power tool (4) and an external communication device (3), where the hand-held power tool (4) comprises a tool communication unit (2) and a combustion engine (7). The power tool communication unit (2) comprises a communication device (5) and a tool control unit (6), and is adapted for wireless communication with the external communication device (3) via a communication channel (12). The external communication device (3) comprises a device control unit (18) and is adapted to provide automatically acquired data to the tool control unit (6) via the communication channel (12). The tool control unit (6) is adapted to control tool parameters comprising at least one of air/fuel ratio and ignition of the combustion engine (7) in dependence of said data.

Inventors:
LUNDBLAD, Björn (Bårarp 15, Jönköping, 566 28, SE)
EKLUND, Henrik (Ljungarpsvägen 15A, Tenhult, 560 30, SE)
Application Number:
SE2018/051204
Publication Date:
May 31, 2019
Filing Date:
November 21, 2018
Export Citation:
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Assignee:
HUSQVARNA AB (Drottninggatan 2, Huskvarna, 561 82, SE)
International Classes:
F02D35/02; B25F5/00; F02D3/00; F02D41/22; F02P5/15; G01L23/22; H04W4/80
Foreign References:
US20080133177A12008-06-05
US20060288982A12006-12-28
US4290398A1981-09-22
Download PDF:
Claims:
CLAIMS

1. A sound wave detecting arrangement (3, 30) comprising a sound wave sensing device (16, 31 ) and a device control unit (18, 32), characterized in that the sound wave sensing device (16, 31 ) is adapted to detect sound from a running combustion engine (7), and that the device control unit (18, 32) is adapted to perform signal processing on the detected sound in order to retrieve data in the form of one or more desired engine parameters.

2. The sound wave detecting arrangement (3) according to claim 1 , characterized in that the sound wave detecting arrangement (3) is adapted to present data in the form of one or more desired engine parameters to a user, and/or to communicate data in the form of one or more desired engine parameters to an engine control unit (6), where the engine control unit (6) is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine (7) in dependence of said data.

3. The sound wave detecting arrangement (30) according to claim 1 , characterized in that the sound wave detecting arrangement (30) is adapted to communicate data in the form of one or more desired engine parameters to an engine control unit (6), where the engine control unit (6) is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine (7) in dependence of said data.

4. The sound wave detecting arrangement (3) according to any one of the claims 1 -3, characterized in that said one or more desired engine parameters comprises at least one of engine speed and knock level. 5. A power tool communication system (1 ) comprising a hand-held power tool (4) and an external communication device (3), where the hand-held power tool (4) comprises a tool communication unit (2) and a combustion engine (7), where the power tool communication unit (2) comprises a communication device (5) and a tool control unit (6) and is adapted for wireless communication with the external communication device (3) via a communication channel (12), characterized in that the external communication device (3) comprises a device control unit (18) and is adapted to provide automatically acquired data to the tool control unit (6) via the communication channel (12), where the tool control unit (6) is adapted to control tool parameters comprising at least one of air/fuel ratio and ignition of the combustion engine (7) in dependence of said data.

6. The power tool communication system (1 ) according to claim 5, characterized in that said data comprises automatically acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, present country, sound and altitude defined as height over sea level.

7. The power tool communication system (1 ) according to claim 6, characterized in that the device control unit (18) is adapted to extract data from acquired information by means of data processing or signal processing.

8. The power tool communication system (1 ) according to any one of the claims 6 or 7, characterized in that at least one of the present country, altitude, time and date are acquired by means of a GNSS, Global Navigation Satellite System, unit (19) comprised in the external communication device (3).

9. The power tool communication system (1 ) according to any one of the claims 6-8, characterized in that the present time and date are acquired by means of a real-time clock unit (27).

10. The power tool communication system (1 ) according to any one of the claims 6-9, characterized in that the power tool communication system (1 ) is adapted to determine the time between a stop of the combustion engine (7) and the next start of the combustion engine (7) by means of the acquired data regarding time and date.

1 1 . The power tool communication system (1 ) according to any one of the claims 5-10, characterized in that the tool control unit (6) is adapted to control said tool parameters by controlling an air/fuel ratio control arrangement (8) comprised in the hand-held power tool (4), and ignition timing of the of the combustion engine (7), where the air/fuel ratio control arrangement (8) comprises at least one of a fuel valve (25) and and/or an air intake valve (26). 12. The power tool communication system (1 ) according to any one of the claims 5-1 1 , characterized in that the external communication device (3) is constituted by a smart phone, a laptop computer or a tablet computer.

13. The power tool communication system (1 ) according to any one of the claims 5-12, characterized in that the external communication device (3) comprises at least one sensor device (24), where said sensor device (24) is adapted to detect environmental data including at least one of air pressure, temperature and sound.

14. The power tool communication system (1 ) according to any one of the claims 5-13, characterized in that the external communication device (3) is arranged for Internet connection, and can acquire at least one of present country and weather data via the Internet, where the weather data comprises at least one of air pressure and temperature. 15. The power tool communication system (1 ) according to any one of the claims 5-14, characterized in that the tool communication unit (2) comprises a passive RFID, Radio-frequency identification, tag (10), and that the external communication device (3) comprises an RFID radio unit (13) enabling the external communication device (3) to communicate with the passive RFID tag (10).

16. The power tool communication system (1 ) according to claim 15, characterized in that the RFID tag (10) comprises a memory module (1 1 ) that is arranged to be read/written either by the external communication device (3) via an RFID interface (12), or via a wired interface to the tool control unit (6), enabling reading/writing by the hand-held power tool (4).

17. The power tool communication system (1 ) according to any one of the claims 5-16, characterized in that the external communication device (3) is adapted to acquire sound information by means of a sound wave detecting device (16), where, by means of said sound information, the power tool communication system (1 ) is arranged to extract data in the form of at least one of engine speed and knock level. 18. A method for a power tool communication system (1 ), characterized in that the method comprises:

(22) providing automatically acquired data from an external communication device (3) to a tool control unit (6) used in a hand-held power tool (4); and

(23) Controlling tool parameters comprising at least one of air/fuel ratio and ignition of a combustion engine (7) used in the hand-held power tool (4), in dependence of said data.

19. The method according to claim 18, characterized in that said data comprises automatically acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, sound and altitude defined as height over sea level.

20. The method according to claim 19, characterized in that the method comprises determining the time between a stop of the combustion engine (7) and the next start of the combustion engine (7) by means of the acquired data regarding time and date.

21 . The method according to any one of the claims 18-20, characterized in that the method comprises controlling said tool parameters by controlling an air/fuel ratio control arrangement (8) comprised in the hand-held power tool (4), and ignition timing of the of the combustion engine (7).

22. The method according to any one of the claims 18-21 , characterized in that the method comprises acquiring sound information and extracting data, from said sound information, in the form of at least one of engine speed and knock level.

Description:
TITLE

A power tool communication system

TECHNICAL FIELD

The present disclosure relates to a power tool communication system comprising a hand-held power tool and an external communication device, where the hand-held power tool comprises a tool communication unit and a combustion engine. The power tool communication unit comprises a communication device and a tool control unit, and is adapted for wireless communication with the external communication device via a communication channel.

BACKGROUND

In the case of a hand-held power tool such as a chain saw, a power tool communication system can be used for monitoring running characteristics of the power tool, as well as ambient temperature and other environmental characteristics. This is described in US 201 1056451 where a combustion engine is used in a hand held power tool, for example a motor chain saw. In order to determine start conditions, a temperature sensor is provided in an electronic control unit to detect ambient temperature, i.e. a temperature outside of the engine itself.

US2010269787 relates to a control apparatus for a general-purpose internal combustion engine where there is an ambient temperature sensor and an engine temperature sensor. It is, however, disadvantageous to have sensor devices exposed to the harsh environment of a combustion engine, and it is therefore desired to obtain a power tool communication system that avoids sensors that are exposed to the harsh environment of a combustion engine. SUMMARY

It is an object of the present disclosure to provide a power tool communication system that avoids sensors that are exposed to the harsh environment of a combustion engine. Said object is obtained by means of a power tool communication system comprising a hand-held power tool and an external communication device, where the hand-held power tool comprises a tool communication unit and a combustion engine. The power tool communication unit comprises a communication device and a tool control unit, and is adapted for wireless communication with the external communication device via a communication channel. The external communication device comprises a device control unit and is adapted to provide automatically acquired data to the tool control unit via the communication channel. The tool control unit is adapted to control tool parameters comprising at least one of air/fuel ratio and ignition of the combustion engine in dependence of said data.

Said object is also obtained by means of a method for a power tool communication system, where the method comprises providing data from an external communication device to a tool control unit used in a hand-held power tool. The method further comprises controlling tool parameters comprising at least one of air/fuel ratio and ignition of a combustion engine used in the hand-held power tool, in dependence of said data.

According to some aspects, said data comprises automatically acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, present country, sound and altitude defined as height over sea level.

According to some aspects, at least one of the present country, altitude, time and date are acquired by means of a GNSS, Global Navigation Satellite System, unit comprised in the external communication device.

According to some aspects, the power tool communication system is adapted to determine the time between a stop of the combustion engine and the next start of the combustion engine by means of the acquired data regarding time and date.

According to some aspects, the tool control unit is adapted to control said tool parameters by controlling an air/fuel ratio control arrangement comprised in the hand-held power tool, and ignition timing of the of the combustion engine. The air/fuel ratio control arrangement comprises at least one of a fuel valve and and/or an air intake valve.

According to some aspects, the external communication device is constituted by a smart phone, a laptop computer or a tablet computer.

According to some aspects, the external communication device comprises at least one sensor device, where said sensor device is adapted to detect environmental data including at least one of air pressure, temperature and sound.

According to some aspects, the external communication device is arranged for Internet connection, and can acquire at least one of present country and weather data via the Internet, where the weather data comprises at least one of air pressure and temperature.

According to some aspects, the tool communication unit comprises a passive RFID, Radio-frequency identification, tag, and the external communication device comprises an RFID radio unit enabling the external communication device to communicate with the passive RFID tag.

According to some aspects, the external communication device is adapted to acquire sound information by means of a sound wave detecting device. By means of said sound information, the power tool communication system is arranged to extract data in the form of at least one of engine speed and knock level.

Said object is also obtained by means of a sound wave detecting arrangement comprising a sound wave sensing device and a device control unit. The sound wave sensing device is adapted to detect sound from a running combustion engine, and that the device control unit is adapted to perform signal processing on the detected sound in order to retrieve data in the form of one or more desired engine parameters.

According to some aspects, the sound wave detecting arrangement is adapted to present data in the form of one or more desired engine parameters to a user, and/or to communicate data in the form of one or more desired engine parameters to an engine control unit, where the engine control unit is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine in dependence of said data. According to some aspects, the sound wave detecting arrangement is adapted to communicate data in the form of one or more desired engine parameters to an engine control unit, where the engine control unit is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine in dependence of said data.

According to some aspects, said one or more desired engine parameters comprises at least one of engine speed and knock level.

A number of advantages are provided by means of the present disclosure, mainly no sensors need to be positioned at the power tool and its often relatively harsh environment. This implies better robustness and lower sensor cost and implies that there is no need for physical adaptation of a power tool-mounted sensor to different tool versions. This means that it will be very easy to adapt said sensors and application to any power tool according to the above.

The existing features and computational power and/or user interface capabilities of an external communication device such as a smart phone can be used. Often a user already has such an external communication device, and in this case, the implementation cost is relatively low. In addition, the computation power of an external communication device such as a smart phone is often much higher than a control unit of a power tool, and is therefore more suitable to process acquired information.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will now be described more in detail with reference to the appended drawings, where:

Figure 1 shows a schematical view of a power tool communication system; Figure 2 shows a flowchart of a method according to the present disclosure; and

Figure 3 shows a schematical view of a hand-held power tool with a sound wave detecting arrangement.

DETAILED DESCRIPTION

The inventive concept will now be described more fully hereinafter, and can, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Like numbers refer to like elements throughout the description. Where applicable, any step or feature illustrated by dashed lines should be regarded as optional. A first example will now be described with reference to Figure 1 , where a power tool communication system 1 is shown, where the power tool communication system 1 comprises a tool communication unit 2 and an external communication device 3. The tool communication unit 2 is comprised in a hand-held power tool 4 such as a chain saw, where the power tool communication unit 2 is adapted for wireless communication with the external communication device 3 via communication channel 12. For reasons of clarity, the tool communication unit 2 is shown enlarged under the power tool 4.

The hand-held power tool 4 comprises a combustion engine 7 such as for example a two-stroke engine, and a fuel valve 25.

The external communication device 3 is according to some aspects constituted by a smart phone, a laptop computer, a tablet computer, or any other electronic device capable of communicating wirelessly with the power tool communication unit 2 while also providing a suitable user interface, and comprises a device control unit 18. In the following, the external communication device 3 will be exemplified as being constituted by a so-called smart phone. The wireless communication, enabling exchange of data between the external communication device 3 and the power tool communication unit 2, is according to some aspects accomplished by means of Bluetooth, Wi-Fi or another local radio arrangement, or alternatively an IR (Infrared) communication arrangement. Examples will be discussed later.

The power tool communication unit 2 comprises a communication device 5 and a tool control unit 6, where the tool control unit 6 is arranged to obtain tool information, to determine certain operational parameters such as running speed, and to control certain operational parameters.

According to the present disclosure, the external communication device 3 is adapted to provide automatically acquired data to the tool control unit 6 via the communication channel 12, where the tool control unit 6 is adapted to control tool parameters comprising at least one of an air/fuel ratio and ignition of the combustion engine 7 in dependence of said data. Said data comprises automatically acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, and altitude defined as height over sea level. In the case of data being extracted from information according to the above, the device control unit 18 is arranged to perform data processing in order to provide said data.

According to some aspects, the tool control unit 6 is adapted to control said parameters by controlling an air/fuel ratio control arrangement 8, comprised in the hand-held power tool 4, and ignition timing of the combustion engine 7. According to some aspects, the air/fuel ratio control arrangement 8 comprises a fuel valve 25 and and/or an air intake valve 26. According to some aspects, control of ignition timing comprises control of ignition angle.

In this context, automatically acquired means that a user does not have to actively enter any data manually, but that the external communication device 3 is adapted to automatically gather the data, for example by means of the Internet or by means of sensor devices. According to some aspects, a user can manually initiate acquiring the data in question, but the process of acquiring data is running automatically.

The altitude, time and date are according to some aspects acquired by means of a GPS (Global Position System) unit 19 comprised in the external communication device 3. Having knowledge of the altitude, the tool control unit 6 is enabled to determine a suitable fuel supply and ignition timing. According to some aspects, the external communication device 3 is arranged for Internet connection, and can acquire weather data via the Internet, where the weather data can comprise air pressure and temperature. According to some aspects, the external communication device 3 comprises a real-time clock unit 27, from which real-time clock unit 27 time and date can be acquired.

Via the Internet connection, and/or via the GPS unit 19, the present country can be determined. Using knowledge about the present country, the tool control unit 6 is according to some aspects adapted to estimate the expected fuel quality and mixture.

According to some aspects, the external communication device 3 comprises one or more sensor devices 24 that are adapted to detect environmental data such as for example air pressure, temperature, humidity/moisture and sound.

Detected and/or otherwise acquired data can be used in many ways, according to some aspects to determine fuel supply and ignition setting at start-up, as well as during operation.

By means of the acquired time and date, the time since last run can be determined and communicated to the tool control unit 6 before start, i.e. the time between the last stop of the combustion engine 7 to the next start of the combustion engine 7. This time from the last stop of the combustion engine 7 is useful for determining air/fuel ratio and ignition timing at the time of the next start.

Some environmental parameters can also be estimated by means of the acquired time and date that confers information about time of year. The tool control unit 6 can use this information to set engine start parameters so that start behavior is optimized for varying starting conditions. Information regarding parameters such as temperature, altitude and moisture can be used for optimizing engine parameters both at start and during operation of the hand-held tool 4. The output power of the engine is, among other things, affected by the density of the air which varies with the air pressure. If the air pressure is measured, the tool control unit 6 can calculate the current density of the air and adjust the air/fuel ratio accordingly. In this way, the air/fuel ratio is always set to an optimal value, independent of variations in air density.

More detailed examples of how detected and/or otherwise acquired data can be used will be discussed later. According to some aspects, the external communication device 3 is adapted to function as a control panel for change of settings of the power tool 4, including one or more of selection of fuel type, theft protection and a lock/unlock functionality. According to some further aspects, the external communication device 3 is adapted to receive data from the power tool communication unit 2, including one or more of accumulated operating time, error logs and running characteristics.

According to some aspects, via the Internet, a user is also able to connect the external communication device 3 to a power tool manufacturer/supplier backend Internet service 14 via an Internet channel 20 to store or receive information, for example:

- Inform the user regarding different running modes.

- Guide the user through calibration of the product, this can be according to some aspects be made with spoken instructions in a Bluetooth headset, or Wireless Hearing Protector with Bluetooth.

- Develop running instructions spoken to the end user, to inform the end user to use the product in the most efficient way.

- Change parameters / firmware over the air.

- Activate theft protection. As indicated above, information regarding time and date, indicating when the combustion engine 7 was shut off last time, constitute useful information at start-up. Other such information that is useful at start-up include weather data, which weather data comprises air pressure and temperature. It is thus desirable to communicate one or more of the above to the tool control unit 6 before start of the combustion engine 7. When the combustion engine 7 is not running, before start-up, no electrical power is generated, and therefore, according to some aspects, a battery 9 is used for powering the tool communication unit 2.

A power tool may not be adapted to include a battery, and there are few battery types available that meets the requirements of a combustion engine power tool’s harsh environment, for example:

- Temperature -30 - +125 C.

- Heavy vibrations

- Relatively high life length / storage requirements.

- The cost of a battery that fulfills the tough requirements can be relatively high.

- The physical space available for a battery is limited. According to some aspects, alternatively, the tool communication unit 2 comprises a passive RFID (Radio-frequency identification) tag 10. In this manner a battery is not needed, instead the RFID tag 10 is adapted to collect energy from a nearby RFID reader's interrogating radio waves, here from the external communication device 3 that for this purpose comprises an RFID radio unit 13. The RFID tag 10 comprises a memory module 1 1 such as an EEPROM (Electrically erasable programmable read only memory) that can be read/written either by the external communication device 3 via the communication channel 12, here constituted by an RFID channel 12, or via a wired interface to the tool control unit 6, enabling reading/writing by the power tool 4. By means of this arrangement, data exchange is possible also when no power is generated in the power tool 4, i.e. when the combustion engine 7 is not running, without use of a battery or any other type of electrical source. This arrangement is therefore both cost effective and robust.

Depending on the energy level transferred over the RFID channel 12, either only the RFID tag 10, or both the RFID tag 10 and the tool control unit 6, can be powered via the RFID channel 12. Data exchange is done by reading/writing to the memory module 1 1 . A lot of alternative ways of communicating by reading/writing to the memory module 1 1 are possible; a relatively uncomplicated alternative is that a number of memory module memory addresses are reserved for information from the hand-held power tool 4 to the external communication device 3, and a number of other memory addresses are reserved for information from the external communication device 3 to the power tool 4.

Each parameter (data to be transferred) is dedicated a pre-defined memory address. For data to be transferred from the hand-held power tool 4 to the external communication device 3, the hand-held power tool 4 is arranged to measure/calculate all parameters regularly, and store the current value in the dedicated memory address in the memory module 1 1. The external communication device 3 is arranged to retrieve the data in question by reading the corresponding memory addresses and extracts the appropriate parameter data.

There are several standards/frequencies that can be used for passive transponders. Among other things, the radio frequencies used differ. The maximum distance between the external communication device 3 and the RFID tag 10 varies with the transmit frequency used and the power of the RFID radio unit 13 of the external communication device 3. Depending on the maximum distance between the external communication device 3 and the RFID tag 10 and the actual distance between the external communication device 3 and the RFID tag 10, user operation of the communication will differ. If the maximum distance between the external communication device 3 and the RFID tag 10 is relatively short, the external communication device 3 must be held relatively close to the tag. If said distance is relatively long, the external communication device 3 can for example be kept in a user’s pocket.

Readers for passive tags of the NFC (Near Frequency Communication) standard are available in most cellular phones. This is a specialized subset within the RFID family. This means that if the NFC standard is used, a standard cellular phone can be used as a reader/writer of the RFID tag 10 in the power tool 4. However, NFC is limited to a relatively short maximum distance between the external communication device 3 and the RFID tag 10. There are several other RFID standards that supports communication over longer distances. However, those standards are normally not supported in cellular phones. Instead, a separate RFID reader unit 15 is needed to communicate with the RFID tag 10 in the power tool 4. Such a separate RFID reader unit 15 is according to some aspects adapted to function as a gateway to forward the information via e.g. Bluetooth to the external communication device 3. Such a separate RFID reader is according to some aspects comprised in a user’s hearing protection or protective clothing. Such a separate RFID reader unit 15 is according to some aspects implemented as a separate device.

According to the example above, communication between the external communication device 3 and the RFID tag 10 is possible both when the combustion engine 7 is running, and when it is not running.

According to some aspects, the external communication device 3 is adapted to acquire sound information by using a microphone 16 mounted on the external communication device 3, or connected to the external communication device 3 wirelessly or in a wired fashion. Generally, a sound wave sensing device 16 is adapted to provide said sound information. By means of engine sound information, it is possible to extract engine parameters such as speed and/or knock level. This makes it possible to detect engine parameters using a remote sensor at a safe distance from the power tool 4, away from the harsh environment of the handheld power tool 4.

The computation power of the external communication device 3 by means of the device control unit 18, which in the case of a smart phone often much more powerful than the tool control unit 6 can be used to analyze the sound information recorded by the microphone by means of signal processing. Also, the external communication device 3 can be adapted to present information extracted from the sound information to the user.

When the sound information from the combustion engine 7 has been recorded, signal processing is used to retrieve data in the form of one or more desired engine parameters.

Below a number of engine parameters are listed: Engine speed, Knock level and First ignition at start. These parameters are possible to detect via sound information detected by e.g. a microphone. In addition, for all parameters also some applications (examples, not limited to this) that uses the detected engine parameter as input, are listed. These applications are according to some aspects be implemented in the external communication device 3. The purpose is to improve the handheld power tool performance/robustness and/or for the convenience of the user.

Engine speed

Several applications, using the engine speed as in-data, can be implemented.

- Application for user guidance when adjusting the needles of a manually tuned carburetor comprised in the combustion engine 7.

- Application for logging of data, such as speed versus time, when using the power tool 4.

Knock level

Knock is a type of abnormal combustion that, when severe, can cause major engine damage. The knock level depends on several factors such as fuel type, temperature, ignition timing etc.

- Application to optimize the knock level of the hand-held power tool dynamically when the engine is running. The knock level is optimized to achieve maximum performance without risk of damaging the engine.

According to some aspects, detected knock level data can be used in the tool control unit 6 for automatic control of the knock level.

First ignition at start

When a handheld power tool using manual choke shall be started, the user has to decide, if choke shall be used or not, and if choke is used— when to deactivate it. When choke is used, it is crucial to deactivate the choke at the right time, otherwise it may be impossible to start the engine.

- Application to facilitate start of the handheld power tool.

Most of the applications also require tool specific parameters, i.e. parameters specific for the power tool in question, to be available in the external communication device 3. E.g., the speed for maximum power varies with variants. The tool variant specific parameters may either be downloaded to a memory module 17 comprised in the external communication device 3 before the tool is started, or be retrieved via a manufacturer/supplier backend Internet service 14 while the tool is running.

The same external communication device 3 can according to some aspects be used together with any power tool variant; each time the user wants to run a new power tool variant, the external communication device 3 is configured to use the parameters, e.g. the speed for maximum power, applicable for that power tool variant. This parameter configuration may either be done manually by selecting the current tool variant manually in a user interface of the external communication device 3, or automatically.

An example of automatic configuration is to use an RFID tag 10 as described above, where the RFID tag 10 further contains a tool variant ID and possibly also a unique ID for that specific power tool. By reading the RFID tag 10 before start, the application of the external communication device 3 is automatically configured external communication device 3 is according to some aspects adapted to inform the user of the current status, e.g. if the speed for maximum power is reached or not.

According to some aspects, it is assumed that:

- The tool specific parameters are available in a local memory of the external communication device 3.

- The identification is done manually by selecting the tool variant manually by means of the external communication device 3.

- The information to the user, when running the product, is done by spoken instructions to the ear protection device. The spoken instructions are generated in the external communication device 3 and is transferred to the audio ear protection device wirelessly, for example via Bluetooth.

With the above assumption, according to some aspects, one or more of the below applications are implemented for the external communication device 3:

Application for user guidance when adjusting the needles of a manually tuned carburetor

- Start the application in the external communication device 3. - Select the tool variant in the application. When the tool variant is set, the application can retrieve the optimum speed at high and low speed used when calibrating the needles of the carburetor.

- Start the handheld power tool. The application detects that the tool is started and guides the user through the calibration process by spoken instructions: o The application tells the user what needle screw to start with and how to actuate the throttle.

o During the calibration the application detects the engine speed and tells the user in what direction to adjust the needle screws.

Application for logging of data, speed versus time, when using the power tool

Start the application in the external communication device 3.

- Enter a unique ID for the particular tool, used to identify the logged data later.

- When the tool is started and used, the application records the engine speed and according to some aspects performs signal processing of the acquired data to retrieve additional parameters such as e.g. a vibration level the user is exposed to. When the user stops using the tool, the application can use the collected data and calculate/extract/present statistics of usage. Optionally, if the external communication device 3 is connected to the Internet, the data can be sent to a manufacturer/supplier backend Internet service 14 and be used for further analysis.

Application to help the user adjust the carburetor of the power tool such that maximum output from the power tool is obtained without risk of engine damage

- Start the application in the external communication device 3.

- Select the tool variant in the application. When the tool variant is set, the application can retrieve the allowable knock level limits for the actual tool variant.

- The application records sound from the engine and extracts engine speed and knock level from the acquired data. By comparing the actual knock level with the limit values, the application is adapted to instruct the user, by spoken instructions, to adjust the carburetor settings to achieve optimum engine performance and robust functionality of the engine, without risk of engine damage. It is possible to change the knock level by adjusting the carburetor needle since the needles adjusts the air/fuel ratio.

Application to facilitate start of the power tool

- Start the application in the external communication device 3.

- Select the tool variant and unique ID for this particular power tool in the application. Parameters used when detecting the first ignition of the present power tool variant is retrieved by the application.

- The application recommends to enable or disable the choke before pulling the start cord. The recommendation is based on e.g. time since last start, ambient temperature etc.

- If choke is recommended:

o The application detects the first ignition. When the first ignition is detected, the application instructs the user, by spoken instructions, to disable the choke. This is important since when choke is used, it is crucial to deactivate the choke at the right time, otherwise it may be impossible to start the engine.

Generally, according to the present disclosure, no sensors need to be positioned at the hand-held power tool 4 and its often relatively harsh environment. This implies better robustness and lower sensor cost and implies that there is no need for physical adaption of a power tool-mounted sensor to different tool versions. This means that it will be very easy to adapt said sensors and application to any power tool according to the above.

The existing features and computational power and/or user interface capabilities of an external communication device 3 can be used. Often a user already has an external communication device 3 in the form of smart device such as a cellular phone. In this case, the implementation cost is relatively low. In addition, the computation power of an external communication device 3 according to the above is often much higher than the tool control unit 6.

In order to enable the external communication device 3 to provide sensor data that normally not is obtainable from a smart phone or the like, and/or to enhance such capabilities, and in order to enable the external communication device 3 to communicate with an RFID tag, the power tool communication system 1 comprises one or more add-on units 21 that are connectable to the external communication device 3, for example via an USB (Universal Serial Bus) connector or the like. Such an add-on unit 21 could comprise sensors for at least one of temperature, humidity and air pressure, as well as an RFID communication unit and a suitable microphone. An add-on unit according to the above can according to some aspects be connected to the external communication device 3 via a wireless connection such as for example Bluetooth.

With reference to Figure 2, the present disclosure also relates to a method for a power tool communication system, where the method comprises:

22: Providing data from an external communication device 3 to a tool control unit 6 used in a power tool.

23: Controlling tool parameters comprising at least one of an air/fuel ratio, and ignition of a combustion engine 7 used in the hand-held power tool 4, in dependence of said data.

As mentioned previously, according to some aspects, controlling said parameters is performed by controlling an air/fuel ratio control arrangement 8, comprised in the hand-held power tool 4, and ignition timing of the combustion engine 7. According to some aspects, the air/fuel ratio control arrangement 8 comprises a fuel valve 25 and/or an air intake valve 26. According to some aspects, control of ignition timing comprises control of ignition angle. According to some aspects, the fuel valve 25 is constituted by an electrically controlled bi-stable valve. According to some aspects, the air/fuel ratio control arrangement 8 comprises a fuel injector in the case of a fuel injection system, being used. According to some aspects, the air intake valve 26 is the throttle valve. The present disclosure is not limited to the examples above, but may vary freely within the scope of the appended claims. For example, the external communication device 3 may have many alternative degrees of equipment and features, such as a GPS unit 19, being arranged for Internet connection, an RFID radio unit 13, a sound wave sensing device 16, a Bluetooth unit 19 etc. All this equipment and all these features are more or less optional and can be comprised in different combinations; the external communication device 3 is, however, adapted to provide data to the tool control unit 6, where said data comprises acquired information regarding, or extracted from, at least one of a number of different parameters such as for example weather, time, date, air pressure, temperature, sound and altitude defined as height over sea level. The optional equipment is shown in Figure 1 with dashed lines in order to indicate that its presence depends on a present configuration of the external communication device 3.

The hand-held power tool 4 does not need to be a chain saw, but can be any type of hand-held power tool. Examples of such power tools are trimmers, hedge trimmers, brush cutters, chainsaws, power cutters and blowers.

The tool control unit 6 is constituted by one single control unit, or by several separate control units such as an engine control unit and a communication control unit. According to some aspects, there is a separate ignition control unit.

The GPS unit 19 is generally constituted by a GNSS (Global Navigation Satellite System) unit 19.

According to some aspects, the external communication device 3 is constituted by, or at least comprises, a sound wave detecting arrangement 3 comprising a sound wave sensing device 16 and a device control unit 18, The sound wave sensing device 16 is adapted to detect sound from a running combustion engine 7, and the device control unit 18 is adapted to perform signal processing in order to retrieve data in the form of one or more desired engine parameters.

The sound wave detecting arrangement 3 is adapted to present data in the form of one or more desired engine parameters to a user, and/or to communicate data in the form of one or more desired engine parameters to an engine control unit 6.

According to some aspects, the engine control unit 6 is comprised in a hand-held power tool 4 and is constituted by the tool control unit 6 according to the above. The hand-held power tool 4 also comprises said combustion engine 7. It is not necessary to have an external communication device 3 that is constituted by, or at least comprises, a sound wave detecting arrangement. Instead, according to some aspects and with reference to Figure 3, a hand-held power tool 4 comprises a sound wave detecting arrangement 30, a combustion engine and a tool control unit 6. The sound wave detecting arrangement 30 comprises a sound wave sensing device 31 and a device control unit 32. The sound wave sensing device 31 is adapted to detect sound from the running combustion engine 7, and the device control unit 32 is adapted to perform signal processing in order to retrieve data in the form of one or more desired engine parameters. The sound wave detecting arrangement 30 is adapted to communicate data in the form of one or more desired engine parameters to an engine control unit 6.

In any case, irrespective of if an external communication device 3 is constituted by, or at least comprises, a sound wave detecting arrangement or if a hand-held power tool 4 comprises a sound wave detecting arrangement 30, the engine control unit 6 is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine 7 in dependence of said data. According to some aspects, said one or more desired engine parameters comprises at least one of engine speed and knock level.

Signal processing in the context of the present application is well known in the art, according to some aspects comprising deriving frequency components by means of for example FFT (Fast Fourier Transform) or similar, and will not be described further here.

Generally, the present disclosure relates to a power tool communication system 1 comprising a hand-held power tool 4 and an external communication device 3, where the hand-held power tool 4 comprises a tool communication unit 2 and a combustion engine 7, where the power tool communication unit 2 comprises a communication device 5 and a tool control unit 6 and is adapted for wireless communication with the external communication device 3 via a communication channel 12. The external communication device 3 comprises a device control unit 18 and is adapted to provide automatically acquired data to the tool control unit 6 via the communication channel 12, where the tool control unit 6 is adapted to control tool parameters comprising at least one of air/fuel ratio and ignition of the combustion engine 7 in dependence of said data.

According to some aspects, said data comprises automatically acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, present country, sound and altitude defined as height over sea level. According to some aspects, the device control unit 18 is adapted to extract data from acquired information by means of data processing or signal processing.

According to some aspects, at least one of the present country, altitude, time and date are acquired by means of a GNSS, Global Navigation Satellite System, unit 19 comprised in the external communication device 3.

According to some aspects, the present time and date are acquired by means of a real-time clock unit 27. According to some aspects, the power tool communication system 1 is adapted to determine the time between a stop of the combustion engine 7 and the next start of the combustion engine 7 by means of the acquired data regarding time and date.

According to some aspects, the tool control unit 6 is adapted to control said tool parameters by controlling an air/fuel ratio control arrangement 8 comprised in the hand-held power tool 4, and ignition timing of the of the combustion engine 7, where the air/fuel ratio control arrangement 8 comprises at least one of a fuel valve 25 and and/or an air intake valve 26. According to some aspects, the external communication device 3 is constituted by a smart phone, a laptop computer or a tablet computer. According to some aspects, the external communication device 3 comprises at least one sensor device 24, where said sensor device 24 is adapted to detect environmental data including at least one of air pressure, temperature and sound. According to some aspects, the external communication device 3 is arranged for Internet connection, and can acquire at least one of present country and weather data via the Internet, where the weather data comprises at least one of air pressure and temperature. According to some aspects, the tool communication unit 2 comprises a passive RFID, Radio-frequency identification, tag 10, and that the external communication device 3 comprises an RFID radio unit 13 enabling the external communication device 3 to communicate with the passive RFID tag 10. According to some aspects, the RFID tag 10 comprises a memory module 1 1 that is arranged to be read/written either by the external communication device 3 via an RFID interface 12, or via a wired interface to the tool control unit 6, enabling reading/writing by the hand-held power tool 4. According to some aspects, the external communication device 3 is adapted to acquire sound information by means of a sound wave sensing device 16, where, by means of said sound information, the power tool communication system 1 is arranged to extract data in the form of at least one of engine speed and knock level. Generally, the present disclosure also relates to a method for a power tool communication system, where the method comprises:

22: providing data from an external communication device 3 to a tool control unit 6 used in a hand-held power tool 4; and

23: Controlling tool parameters comprising at least one of air/fuel ratio and ignition of a combustion engine 7 used in the hand-held power tool 4, in dependence of said data. According to some aspects, said data comprises acquired information regarding, or extracted from, at least one of weather, time, date, air pressure, temperature, sound and altitude defined as height over sea level. According to some aspects, the method comprises determining the time between a stop of the combustion engine 7 and the next start of the combustion engine 7 by means of the acquired data regarding time and date.

According to some aspects, the method comprises controlling said tool parameters by controlling an air/fuel ratio control arrangement comprised in the hand-held power tool, and ignition timing of the of the combustion engine.

According to some aspects, the method comprises acquiring sound information and extracting data, from said sound information, in the form of at least one of engine speed and knock level.

Generally, the present disclosure also relates to a sound wave detecting arrangement 3, 30 comprising a sound wave sensing device 16, 31 and a device control unit 18, 32. The sound wave sensing device 16, 31 is adapted to detect sound from a running combustion engine 7, and that the device control unit 18, 32 is adapted to perform signal processing on the detected sound in order to retrieve data in the form of one or more desired engine parameters.

According to some aspects, the sound wave detecting arrangement 3 is adapted to present data in the form of one or more desired engine parameters to a user, and/or to communicate data in the form of one or more desired engine parameters to an engine control unit 6, where the engine control unit 6 is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine 7 in dependence of said data.

According to some aspects, the sound wave detecting arrangement 30 is adapted to communicate data in the form of one or more desired engine parameters to an engine control unit 6, where the engine control unit 6 is adapted to control engine parameters comprising at least one of air/fuel ratio and ignition of the combustion engine 7 in dependence of said data.

According to some aspects, said one or more desired engine parameters comprises at least one of engine speed and knock level.