Patent Description:
Patent literature <NUM> discloses a work management apparatus including a work information acquisition unit that acquires work information related to the content of work, a positional information acquisition unit that acquires positional information on a place of work, a workpiece information acquisition unit that acquires workpiece information, and an information management unit that stores the work information, the positional information, and the workpiece information in a storage unit, mapping the information to each other. The work management apparatus further includes a determination unit that determines the properness of a work by referring to data for a design drawing. The result of determining the properness of a work is displayed on a display unit.

[Patent Literature <NUM>] <CIT>
<CIT> describes a fastening tool with a clutch for shutting off transmission of torque, capable of self-diagnosing fastening torque of a screw or the like at low cost without using expensive means such as a torque sensor etc. A fastening tool has a motor, a main shaft engaging with a screw or the like, and a clutch interposed between the motor and the main shaft. The clutch transmits torque from the motor to the main shaft when a load acting on the main shaft is less than a predetermined value, and shuts off torque transmission from the motor to the main shaft when a load acting on the main shaft is equal to or greater than the predetermined value. The fastening tool further has a control unit for controlling the motor. The control unit monitors a current flowing to the motor and determines whether fastening torque is normal or not based on a motor current when transmission of torque from the motor to the main shaft is shut off.

<CIT> relates to a tool and a method for monitoring the condition of a tool. The tool comprises a control device for determining status data of the tool, and a display device for displaying the status data determined by the control device.

<CIT> describes a fault diagnosis system, which comprises an electrically powered tool having a function of storing its own usage history information and a diagnostic device connectable to the electrically powered tool, wherein the diagnostic device reads usage history information of the electrically powered tool from the connected electrically powered tool and, based on the usage history information, identifies a source of an error and a cause of the problem electrically driven tool and provides information on the source of the error and the cause of the problem.

When malfunction occurs in an electric power tool, it becomes difficult to manage the tightening torque of a screw material such as a screw and a bolt precisely. It is therefore desired to build a system for evaluating the current status of an electric power tool and managing the electric power tool properly.

The disclosure addresses the above-described issue, and a general purpose thereof is to provide a technology used for status management of an electric power tool. This purpose is achieved by the subject-matter of the independent claim. Particular embodiments are defined in the dependent claims.

The solution is achieved with a power tool according to claim <NUM>.

Another example not covered by the present invention relates to an electric power tool. The electric power tool includes: a motor; an output shaft on which a front-end tool is adapted to be mounted; a power transmission mechanism that transmits a rotational output of the motor to the output shaft; an acquisition unit that acquires physical quantity data detected while the motor is being rotated; a storage unit that stores the physical quantity data and time information related to time when the physical quantity data is acquired, mapping the physical quantity data and the time information to each other; and a transmission unit that transmits the physical quantity data and the time information to a server system.

<FIG> shows a configuration of an electric power tool system <NUM> according to an embodiment. The electric power tool system <NUM> includes an electric power tool <NUM> and a server system <NUM>. An access point (hereinafter, "AP") <NUM> is interconnected with the electric power tool <NUM>, which is a wireless LAN client, and is connected to an external network <NUM> such as the Internet. A router <NUM> is connected to the server system <NUM> by wire and is connected to the network <NUM>. The electric power tool <NUM> and the server system <NUM> are communicably connected via the network <NUM>.

<FIG> shows functional blocks of the electric power tool <NUM> according to the embodiment. An electric power tool <NUM> includes a housing <NUM>. A driving unit <NUM>, a control unit <NUM>, a communication unit <NUM>, a notification interface <NUM>, a storage unit <NUM>, a detector <NUM>, a clock <NUM>, and a battery <NUM> are provided in the housing <NUM>. The battery <NUM> is mounted on the lower end of the housing <NUM> to supply electric power to the constituting elements of the electric power tool <NUM>. The lower end of the housing <NUM> may be formed as a battery pack separate from the main body of the tool and configured to be removably attached to the main body of the tool. The clock <NUM> is a real-time clock. The clock <NUM> generates current date and time information and supplies the information to the control unit <NUM>.

The driving unit <NUM> includes the motor <NUM>, which is driving source, and a power transmission mechanism <NUM> coupled to a motor shaft <NUM> of the motor <NUM> to drive the output shaft <NUM>. A front-end tool mount <NUM> is coupled to the output shaft <NUM>, and a front-end tool such as a driver that applies a tightening torque to a screw member is adapted to be mounted on the front-end tool mount <NUM>. The power transmission mechanism <NUM> is a mechanism that transmits the rotational output of the motor <NUM> to the output shaft <NUM>. The power transmission mechanism <NUM> may include a planetary gear deceleration mechanism in mesh with a pinion gear attached to the motor shaft <NUM>. The electric power tool <NUM> according to the embodiment is a rotary impact tool, and the power transmission mechanism <NUM> includes an impact mechanism for applying an intermittent rotary impact force to the output shaft <NUM>.

The detector <NUM> detects physical quantity data in the electric power tool <NUM>. The detector <NUM> may include a tightening torque detector <NUM>, a current detector <NUM>, a revolution detector <NUM>, and a vibration detector <NUM>. The tightening torque detector <NUM> detects the tightening torque of the screw member. The tightening torque detector <NUM> may include a magnetostrictive torque sensor attached to the output shaft <NUM> and a rotation angle sensor of the output shaft <NUM>. The torque sensor uses a coil provided in a non-rotated part to detect the variation in magnetic permeability determined by the axial distortion caused by applying a torque to the output shaft <NUM> and outputs a voltage signal determined by the distortion. The rotation angle sensor outputs the rotation angle of the output shaft <NUM>. The tightening torque detector <NUM> uses the voltage signal determined by the distortion and the rotation angle of the output shaft <NUM> to calculate and output the tightening torque of the screw member.

The current detector <NUM> detects an electric current supplied to the motor <NUM>. The revolution detector <NUM> detects the number of revolutions (rotation speed) of the motor <NUM>. The revolution detector <NUM> may be a magnetic rotary encoder, a Hall element IC, etc. that detects the rotation angle of the motor <NUM>. The vibration detector <NUM> detects the vibration generated in the housing <NUM>. The vibration detector <NUM> may be a displacement sensor, a speed sensor, or an acceleration sensor and may be formed by an electromagnetic element, a piezoelectric element, a capacitance element, etc..

The communication unit <NUM> includes a transmission unit <NUM> and a reception unit <NUM>. The communication unit <NUM> may be a module configured to communicate wirelessly with the AP <NUM> according to a communication protocol such as the IEEE802. <NUM> protocol. The communication unit <NUM> may also include a wireless communication function in the fourth-generation mobile communication system. The communication unit <NUM> may not be a wireless communication module but a module configured to communicate with an external device by wire via, for example, a USB cable.

The notification interface <NUM> is an output interface for outputting information to the user. The notification interface <NUM> may include a speaker for audio output of information and/or a display for outputting information on a screen. The storage unit <NUM> is a memory and includes a read only memory (ROM) and a random access memory (RAM). The ROM stores at least identification information (tool ID) for identifying the electric power tool <NUM>. The ROM further stores a control program used by the motor control unit <NUM>. The RAM stores the information transmitted from the transmission unit <NUM> temporarily and stores the information received by the reception unit <NUM> temporarily.

The electric power tool or the entity that executes the method according to the disclosure is provided with a computer. By causing the computer to run a program, the function of the tool or the entity that executes the method according to the disclosure is realized. The computer is comprised of a processor that operates in accordance with the program as a main hardware feature. The disclosure is non-limiting as to the type of the processor so long as the function is realized by running the program. The processor is comprised of one or a plurality of electronic circuits including a semiconductor integrated circuit (IC) or a large-scale integration (LSI). The terms IC and LSI may change depending on the integration degree, and the processor may be comprised of a system LSI, a very large scale integration (VLSI), or an ultra large scale integration (USLI). A field programmable gate array (FPGA) programmed after the LSI is manufactured, or a reconfigurable logic device, in which the connections inside the LSI are reconfigurable or the circuitry blocks inside the LSI can be set up, can be used for the same purpose. The plurality of electronic circuits may be integrated in one chip or provided in a plurality of chips. The plurality of chips may be aggregated in one device or provided in a plurality of apparatuses. The program is recorded in a non-transitory recording medium such as a computer-readable ROM, optical disk, and hard disk drive. The program may be stored in a recording medium in advance or supplied to a recording medium via wide area communication network including the Internet.

The control unit <NUM> is implemented by a computer carried on a control board. The control unit <NUM> has the function for integrated control of the electric power tool <NUM> and performs various processes related to the electric power tool <NUM>. The control unit <NUM> includes an acquisition unit <NUM>, a motor control unit <NUM>, a communication control unit <NUM>, and a notification control unit <NUM>.

The acquisition unit <NUM> acquires physical quantity data detected while the motor <NUM> is being rotated. The physical quantity data detected while the motor <NUM> is being rotated may at least include physical quantity data detected by the detector <NUM>. In other words, the acquisition unit <NUM> acquires the tightening torque value from the tightening torque detector <NUM>, the motor current value from the current detector <NUM>, the number of revolutions of the motor from the revolution detector <NUM>, and the vibration data from the vibration detector <NUM> while the motor <NUM> is being rotated. The acquisition unit <NUM> stores the physical quantity data and time information related to the time when the physical quantity data is acquired in the storage unit <NUM>, mapping the data and the information to each other.

The time information mapped to the physical quantity data may be the absolute time information indicating the current time supplied from the clock <NUM>. The mapped time information may be the relative time information indicating the time elapsed since the reference time (e.g., the date and time of manufacturing or the date and time of first use). In either case, mapping the physical quantity data and the time information to each other ensures that the server system <NUM> can analyze the temporal transition of physical quantity data. As described above, the storage unit <NUM> stores the physical quantity data and the time information related to the time when the physical quantity data is acquired, mapping the data and the information to each other.

The frontward grip portion of the housing <NUM> is provided with a user operation switch <NUM> that can be manipulated by the user. The user operation switch <NUM> may be a trigger switch that can be pulled by the user for manipulation. The motor control unit <NUM> controls on and off of the motor <NUM> in accordance with the manipulation of the user operation switch <NUM> and controls the current applied to the motor <NUM> in accordance with how much the user operation switch <NUM> is manipulated to adjust the number of revolutions of the motor. A target torque value to be achieved by the current work is set in the storage unit <NUM> before the work is started. The motor control unit <NUM> monitors the tightening torque value detected by the tightening torque detector <NUM>. When the tightening torque value reaches the target torque value, the rotation of the motor <NUM> is automatically stopped. The tightening torque of the screw member is managed by performing the control as described above.

The communication control unit <NUM> controls the transmission operation performed by the transmission unit <NUM> and the reception operation performed by the reception unit <NUM>. The communication unit <NUM> is connected to the server system <NUM> via the network <NUM>. In the electric power tool system <NUM> of the embodiment, the communication control unit <NUM> causes the physical quantity data and the time information stored in the storage unit <NUM> to be transmitted from the transmission unit <NUM> to the server system <NUM> after the rotation of the motor <NUM> is stopped. It is preferred that the transmission unit <NUM> transmit the physical quantity data and the time information acquired in relation to a single tightening work to the server system <NUM> after the work is completed.

<FIG> shows functional blocks of the server system <NUM> according to the embodiment. The server system <NUM> includes a communication unit <NUM>, a status evaluation unit <NUM>, a notification unit <NUM>, and a storage apparatus <NUM>. The communication unit <NUM> includes a reception unit <NUM> and a transmission unit <NUM>.

The server system <NUM> may be operated and managed by, for example, an entity manufacturing the electric power tool <NUM>. <FIG> shows that the server system <NUM> is connected only to one electric power tool <NUM>, but the server system <NUM> is connected to a plurality of electric power tools <NUM> and receives the physical quantity data and the time information acquired in the respective electric power tools <NUM>. The transmission unit <NUM> in the electric power tool <NUM> transmits the physical quantity data and the time information to the server system <NUM>, mapping the data and the time information to the tool ID of the electric power tool <NUM>.

The reception unit <NUM> receives the physical quantity data and the time information transmitted from the electric power tool <NUM>. The storage apparatus <NUM> stores the physical quantity data and the time information received, mapping the information to the tool ID of the electric power tool <NUM> The status evaluation unit <NUM> evaluates the level of the status of the electric power tool <NUM> by using the physical quantity data and the time information received. For example, the status evaluation unit <NUM> determines whether the electric power tool is out of order or about to be out of order or determines the level of deterioration, by evaluating the level of the tool status.

The server system <NUM> may be configured to include one or a plurality of processing apparatuses. For example, the server system <NUM> may include a collection apparatus that collects the physical quantity data transmitted from the electric power tool <NUM> and an evaluation apparatus that evaluates the level of the status of the electric power tool <NUM> by using the collected physical quantity data. In this case, the communication unit <NUM> and the storage apparatus <NUM> shown in <FIG> may be provided as features on the side of the collecting apparatus, and the status evaluation unit <NUM> and the notification unit <NUM> may be provided as features on the side of the evaluation apparatus.

<FIG> shows examples of physical quantity data and time information received for a single work. Of the physical quantity data, <FIG> shows a relationship between the tightening torque value and the vibration data. This example shows the variation in the physical quantity data during a period between the time (t1) when the tightening torque value is detected to exceed <NUM> and the time (t2) when the tightening torque value reaches the target torque value (Tt[N·m]) and the motor <NUM> is automatically stopped.

The storage apparatus <NUM> stores a collection of a plurality of sets of physical quantity data and time information acquired for each of the works in the past, mapping the data and information to the tool ID. When the reception unit <NUM> receives the physical quantity data and the time information mapped to the tool ID, the status evaluation unit <NUM> reads the physical quantity data and the time information mapped to the same tool ID from the storage apparatus <NUM> to analyze the temporal transition of the status of the electric power tool <NUM> and determine the level of the status.

More specifically, when the status evaluation unit <NUM> refers to the data for the current tightening torque value and determines that the ultimate tightening torque value is Tt[N·m], the status evaluation unit <NUM> refers to the physical quantity data stored in the past to identify physical quantity data for which the ultimate tightening torque value is Tt[N·m]. The status evaluation unit <NUM> uses data indicating the change in the tightening torque value occurring as works have been performed a predetermined number of (e.g., <NUM>) times in the immediate past to determine an average time (Ts) elapsed since the point of time when the tightening torque value exceeds <NUM> until it reaches Tt[N. For example, the status evaluation unit <NUM> may calculate and maintain, for each ultimate tightening torque value, the average time Ts required to reach the ultimate tightening torque in advance.

The status evaluation unit <NUM> calculates a ratio (R) between the current time required to reach the ultimate value (t2-t1) and the average time Ts as follows: <MAT>.

The status evaluation unit <NUM> evaluates the level of the status of the electric power tool <NUM>, and, in this case, the level of deterioration, in accordance with the R value.

<FIG> shows an example of an evaluation table for the level of deterioration. The evaluation table defines levels of deterioration determined by the R value are defined. The status evaluation unit <NUM> of the embodiment evaluates the status of the electric power tool <NUM> in accordance with the evaluation table. Deterioration of the tool is comprised of a variety of factors such as looseness occurring between components due to friction or the like, position gap between components caused by drop of the tool, contact failure in the electrical system, etc..

For convenience, the evaluation table shown in <FIG> will be explained by only discussing degrees of the magnitude of looseness. "Slightly deteriorated" means that looseness is identified but only in a negligible degree. "Heavily deteriorated" means that looseness has grown so large that a problem with the work efficiency begins to be caused and the tool is one step short of being out of order. "Possibly out of order" means that the tool is in a state that can be referred to as "out of order". As described below, the evaluation result is transmitted to the electric power tool <NUM> and communicated to the user.

The evaluation table shown in <FIG> defines the levels of deterioration determined by the ratio (R). Alternatively, the level of deterioration may be defined in accordance with a difference between the current time required to reach the ultimate value (t2-t1) and the average time Ts.

Given the ultimate tightening torque value Tt[N· m], the variation characteristic of the tightening torque value may differ depending on the type of the front-end tool for the tightening work and the type of the work tightened. Factors that make the variation characteristic differ include a difference in the length of the front-end tool, a difference in the hardness of the work, etc..

Thus, the status evaluation unit <NUM> may refer to the physical quantity data stored in the past to identify the physical quantity data for which the ultimate tightening torque value is Tt[N·m] and then extract the physical quantity data for which the variation characteristic of the vibration data is common. That the vibration characteristic of the vibration data is common means that the work situation such as the type of the front-end tool used and the type of the work is similar. The status evaluation unit <NUM> may extract the physical quantity data in similar work situations and use data indicating the change in the tightening torque value occurring as works have been performed a predetermined number of (e.g., <NUM>) times in the immediate past to determine the average time (Ts') elapsed since the point of time when the tightening torque value exceeds <NUM> until it reaches Tt[N· m]. In this case, the status evaluation unit <NUM> will be evaluating the variation characteristic of the tightening torque value in similar work situations so that the precision of evaluation will be enhanced.

The status evaluation unit <NUM> may evaluate the status of the electric power tool <NUM> by taking the variation characteristic of the value of the current supplied to the motor <NUM> or the variation in the number of revolutions of the motor <NUM> into consideration as well as the vibration data. When the current physical quantity data compared with the physical quantity data in a similar work situation in the past shows that the amount of current supplied to the motor is small or that the number of revolutions of the motor <NUM> is small, for example, the capacity of the battery <NUM> may have dropped. Thus, the status evaluation unit <NUM> may not evaluate the level of deterioration using the evaluation table when it is determined that a characteristic abnormality is caused by a drop in the capacity of the battery <NUM>. This reduces the likelihood that the status evaluation unit <NUM> improperly yields an evaluation "heavily deteriorated" or "possibly out of order" regardless of the fact that the electric power tool <NUM> has not been deteriorated.

The notification unit <NUM> causes the transmission unit <NUM> to transmit evaluation data indicating the result of evaluation by the status evaluation unit <NUM> to the electric power tool <NUM>. In the case the evaluation result is "no problem", the notification unit <NUM> does not cause the transmission unit <NUM> to transmit the evaluation data. In other words, the notification unit <NUM> may cause the transmission unit <NUM> to transmit the evaluation data to the electric power tool <NUM> only when the status evaluation unit <NUM> evaluates the status as "slightly deteriorated", "heavily deteriorated", or "possibly out of order".

In the electric power tool <NUM>, the reception unit <NUM> receives the transmitted evaluation data. The notification control unit <NUM> causes the notification interface <NUM> to communicate the evaluation data. The notification interface <NUM> provides an audio output of the evaluation result from the speaker or provides a screen output of the evaluation result from a display. The user can know the status of the electric power tool <NUM> by referring to the content communicated from the notification interface <NUM>. It is preferred that the user provided with "possibly out of order" notification send the electric power tool <NUM> for repair without delay.

Described above is an explanation based on an embodiment. The embodiment is intended to be illustrative only and it will be understood by those skilled in the art that various modifications to constituting elements and processes could be developed and that such modifications are also within the scope of the present disclosure. The detector <NUM> may further include a temperature detector for detecting temperature and a sound detector for detecting sound.

A summary of an embodiment of the present disclosure is given below. An electric power tool system (<NUM>) according to the present disclosure includes an electric power tool (<NUM>) and a server system (<NUM>). The electric power tool (<NUM>) may include: a motor (<NUM>); an output shaft (<NUM>) on which a front-end tool is adapted to be mounted; a power transmission mechanism (<NUM>) that transmits a rotational output of the motor to the output shaft; an acquisition unit (<NUM>) that acquires physical quantity data detected while the motor is being rotated; a storage unit (<NUM>) that stores the physical quantity data and time information related to time when the physical quantity data is acquired, mapping the data and the information to each other; and a tool-side transmission unit (<NUM>) that transmits the physical quantity data and the time information to the server system (<NUM>). The server system (<NUM>) may include: a server-side reception unit (<NUM>) that receives the physical quantity data and the time information transmitted; and a status evaluation unit (<NUM>) that evaluates a level of a status of the electric power tool (<NUM>) by using the physical quantity data and the time information. The physical quantity data preferably includes vibration data indicating vibration of the electric power tool detected while the motor is being rotated and also includes a tightening torque value.

The server system (<NUM>) may include: a server-side transmission unit (<NUM>) that transmits evaluation data yielded by the status evaluation unit (<NUM>) to the electric power tool (<NUM>), and the electric power tool (<NUM>) may include: a tool-side reception unit (<NUM>) that receives the evaluation data transmitted; and a notification interface (<NUM>) that communicates the evaluation data.

The tool-side transmission unit (<NUM>) may transmit the physical quantity data and the time information to the server system (<NUM>), mapping the physical quantity data and the time information to identification information on the electric power tool (<NUM>), and the server system (<NUM>) may include: a storage apparatus (<NUM>) that stores the physical quantity data and the time information, mapping the physical quantity data and the time information to the identification information on the electric power tool (<NUM>). The status evaluation unit (<NUM>) preferably uses the physical quantity data and the time information stored and mapped to the identification information on the electric power tool to analyze temporal transition of the status of the electric power tool and evaluate the level of the status.

An electric power tool (<NUM>) according to another embodiment of the present disclosure may include: a motor (<NUM>); an output shaft (<NUM>) on which a front-end tool is adapted to be mounted; a power transmission mechanism (<NUM>) that transmits a rotational output of the motor to the output shaft; an acquisition unit (<NUM>) that acquires physical quantity data detected while the motor is being rotated; a storage unit (<NUM>) that stores the physical quantity data and time information related to time when the physical quantity data is acquired, mapping the physical quantity data and the time information to each other; and a transmission unit (<NUM>) that transmits the physical quantity data and the time information to a server system.

The present disclosure can be used in the fields of electric power tools and management of the status of electric power tools.

Claim 1:
An electric power tool system (<NUM>) including an electric power tool (<NUM>) and a server system (<NUM>),
the electric power tool (<NUM>) including:
a motor (<NUM>);
an output shaft (<NUM>) on which a front-end tool is adapted to be mounted;
a power transmission mechanism (<NUM>) that transmits a rotational output of the motor to the output shaft;
an acquisition unit (<NUM>) that acquires physical quantity data detected while the motor is being rotated;
a storage unit (<NUM>) that stores the physical quantity data and time information related to time when the physical quantity data is acquired, mapping the physical quantity data and the time information to each other; and
a tool-side transmission unit (<NUM>) that transmits the physical quantity data and the time information to the server system, mapping the physical quantity data and the time information to identification information on the electric power tool (<NUM>),
the server system (<NUM>) including:
a storage apparatus (<NUM>) that stores past physical quantity data and past time information, mapping the past physical quantity data and the past time information to the identification information on the electric power tool; and
a server-side reception unit (<NUM>) that receives the physical quantity data and the time information transmitted from the tool-side transmission unit (<NUM>) and mapped to the identification information on the electric power tool; and
a status evaluation unit (<NUM>) that reads, from the storage apparatus, the past physical quantity data and the past time information stored and mapped to the identification information same as the identification information mapped to the physical quantity data and the time information which are received by the server-side reception unit (<NUM>), analyzes temporal transition of a status of the electric power tool by using the received physical quantity data and the time information, and the past physical quantity data and the past time information read from the storage apparatus, and evaluates a level of the status of the electric power tool.