DE102018200197A1 - Electrically powered tool having at least one intelligent brake actuator and method of operating a tool - Google Patents

Abstract

Disclosed is an electrically driven tool comprising an electric motor for directly or indirectly driving a tool holder and a tool used in the tool holder, at least one actuator for braking the tool holder, an energy storage or a power source terminal for supplying the electric motor with electrical energy and a control unit for processing at least one user input, wherein the control unit has at least one activatable by user input comfort braking mode for user-defined braking of the tool holder and at least one sensor-based activated by the control unit emergency braking mode for braking the tool holder. Furthermore, a method for operating a tool is disclosed.

Description

The invention relates to an electrically driven tool comprising an electric motor for directly or indirectly driving a tool holder and a tool attachment used in the tool holder, at least one actuator for braking the tool holder, an energy storage or a power source connection for supplying the electric motor with electrical energy and a control unit for processing of at least one user input. Furthermore, the invention relates to a method for operating a tool.

State of the art

There are already electrically powered tools with a comfort brake known. Usually set in such comfort brakes fixed current values or braking times, so that a user can not exert any influence on the braking behavior of the tool.

From the DE 198 099 39 A1 is a braked power tool with a universal motor known. The braked power tool can be adjusted by customizing a braking behavior in the form of a change in the braking time of the universal motor.

The known versions of braked tools can not be adapted or customized. In addition, they offer no expansion options with respect to a sensor.

Disclosure of the invention

The object underlying the invention can be seen to propose an electrically powered tool with improved reliability, work efficiency and increased user comfort

This object is achieved by means of the subject matter of the independent claims. Advantageous embodiments of the invention are the subject of each dependent subclaims.

According to one aspect of the invention, an electrically driven tool is provided with an electric motor for directly or indirectly driving a tool holder and a tool attachment inserted into the tool holder.

The tool also has at least one actuator for braking the tool holder, an energy store or a power source connection for supplying the electric motor with electrical energy and a control unit for processing at least one user input.

The tool attachment which can be inserted into the tool holder or can be received by the tool holder can be for example a drilling tool, a milling tool, a saw blade or a circular saw blade, an abrasive and the like.

According to the invention, the control unit has at least one comfort braking mode which can be activated by user input for user-defined braking of the tool holder and at least one emergency brake mode which can be activated by the control unit in a sensor-based manner for braking the tool holder.

The at least one comfort braking mode allows user-defined braking parameters to be stored in the control unit. The at least one comfort braking mode can in this case also have one or more subordinate braking modes, which can differ in the braking time and / or the brake parameter or a braking characteristic of the electric motor or the tool holder.

The braking parameters can be configured in particular in the control unit as software parameters and / or as hardware parameters. Hardware parameters may be, for example, component values and braking torque curves of the at least one actuator for performing a braking operation.

The at least one comfort braking mode may be configured and triggered by a user. For example, a comfort braking mode can be executed when the tool is switched off.

Advantageously, the braking parameters and thus the braking characteristics of the at least one actuator can be adjusted by the user, for example, to adapt the electrically driven tool to work processes or personal preferences.

The at least one emergency braking mode may be configured by the control unit in the form of automated interventions in the operation of the electrically powered tool. This intervention of the control unit can be carried out, for example, in safety-related triggers.

The at least one emergency braking mode can be analogous to the at least one comfort braking mode have one or more subordinate braking modes.

The at least one emergency braking mode can be executed by the control unit sensor-based in the case of an already occurring trigger or event or anticipatory in the case of an expected trigger or event.

The triggers or events can be determined by an evaluation of sensor measurement data by the control unit. In particular, safety-related triggers can be identified by the control unit when threshold values of the sensor measurement data are exceeded and treated in the context of one or more emergency braking modes.

Alternatively or additionally, the control unit may execute algorithms based on determined sensor measurement data for determining a trigger for the at least one emergency braking mode.

The emergency braking by the at least one actuator can be initiated in a forward-looking manner. As a result, the operational safety and the working efficiency can be increased and the user comfort can be improved.

According to one embodiment of the electrically driven tool, the electrically driven tool has at least one sensor, wherein the control unit is connected in a data-conducting manner to the at least one sensor. As a result, the control unit may preferably have a brake electronics for controlling the at least one actuator or be connected to a brake electronics.

The tool may preferably have integrated sensors which are data-conducting connected to the control unit. The control unit can thus read the sensor measurement data directly or indirectly and use it for evaluation. It is thus possible to respond to security events.

According to a further embodiment of the electrically driven tool, the at least one emergency braking mode can be controlled automatically by the control unit based on measurement data of at least one sensor. As a result, the control unit can intervene quickly and reliably in the operation of the electrically driven tool when triggering events or triggering events are detected.

According to another embodiment of the electrically driven tool, the at least one sensor is an acceleration sensor for detecting an acceleration and an acceleration direction of the tool. As a result, the control unit can perform a so-called "Freefall Detection" and detect whether the tool is just falling in the direction of a floor. Thus, for example, a saw blade may be stopped before it can injure the user, thereby increasing safety in handling the tool.

According to a further embodiment of the electrically driven tool, the at least one sensor is an optical sensor or a Hall sensor for performing a Schnittenderkennung. The optical sensor may in this case be a camera, a LIDAR sensor or a radar sensor, which can measure distances and contours of a workpiece or an environment of the tool.

As a result, for example, an automatic cutting end detection can be realized. Alternatively or additionally, in this case a torque or speed profile of the electric motor can be used in such a detection.

According to a further embodiment of the electrically driven tool, the at least one sensor is a tachometer for determining a speed characteristic of the electric motor. This allows the control unit to perform a monitoring of the speed curve of the electric motor or an operating frequency of the tool holder. For example, based on the speed history and user input, it may be determined when the tool exits the workpiece or has been drilled through the workpiece.

Furthermore, a so-called "kickback" fuse can be realized by the evaluation of the speed signal and / or the acceleration sensor and / or a change in the electric motor current profile. It can be prevented or at least reduced the effect that the tool undergoes a recoil on the workpiece to be machined and can injure the user.

According to a further embodiment of the electrically driven tool, the at least one sensor is a proximity sensor or a touch sensor. It can thus be checked whether the user is in the vicinity of the electrically driven tool. Furthermore, it can be ensured by a proximity sensor, whether the user operates the tool properly or positions his hands on the designated holding elements of the tool.

A corresponding sensor system can be designed, for example, capacitively, inductively, optically, thermally and / or as an ultrasonic sensor system. In addition, a proximity sensor can also be a Radar sensor, LIDAR sensor or a light barrier.

According to a further embodiment, the electrically driven tool has a communication device connected to the control unit for establishing a wireless or wired communication connection. As a result, a functionality of the electrically driven tool can be extended. For example, this can be used to establish a communication connection to a portable device, such as a smartphone or a tablet.

Furthermore, the electrically powered tool can communicate through the communication link with a user's infrastructure or work environment or smart apparel. This can increase the flexibility of the tool.

According to a further embodiment of the electrically driven tool, at least one externally arranged sensor can be coupled to the control unit via the wireless or wired communication connection. In this way, sensors or sensors of a portable device arranged externally in a work environment can be realized for recognizing a safety-critical situation and for initiating emergency braking modes. The electrically powered tool may be shut down or braked directly via the wireless or wired communication link or based on sensor measurement data from external sensors.

In accordance with a further embodiment of the electrically driven tool, when the at least one emergency braking mode is initiated, at least one function can be introduced by the control unit via the wireless or wired communication link. Thus, further measures can be initiated via the wired or wireless communication link. For example, an emergency call can be sent or an alarm siren can be activated by the control unit.

In addition, other tools or machines can be deactivated or activated to increase the security of the user in the environment. Further measures may be the notification of employees and / or insurance. In this case, for example, the location data determined by means of a GPS sensor can be transmitted to a control center. Furthermore, warning lamps can be switched on at the tool and / or in the working environment. This can be done by different transmission technologies, such as Bluetooth, WLAN, ANT, LORA or Powerline.

According to a further embodiment of the electrically driven tool, the actuator for braking the tool holder is an electrically or mechanically driven actuator. Thus, the actuator controlled by the control unit initiate a braking operation of the tool holder.

According to a further embodiment of the electrically driven tool, the control unit is connected to a sensor system for monitoring state values of the electric motor, the energy store and the at least one actuator. As a result, the control unit can monitor the tool as a whole and determine a so-called vital state of the tool. The vital state can be used, for example, to set limit values of the sensor measurement data. In addition, a vital state of the tool can be a safety-relevant event.

According to a further aspect of the invention, a method for operating a tool according to the invention is provided by a control unit of a tool connected in a data-conducting manner with at least one sensor. When operating or when the tool is at standstill, sensor measurement data of the at least one sensor are read out and evaluated to assess at least one safety-critical event.

In a safety-critical event detected by the control unit, at least one emergency braking mode for braking a tool holder is carried out by at least one actuator of the tool.

As long as no safety-critical event has been detected by the control unit of the tool, the tool holder is braked by at least one user-defined comfort braking mode by the at least one actuator.

As a result, in the event of a safety-critical event detected, the at least one comfort mode can be automatically superimposed by at least one emergency braking mode and the tool holder, for example, braked as quickly as possible by the at least one actuator. It can thus be increased work safety of the tool.

• 1 eine schematische Darstellung eines elektrisch angetriebenen Werkzeugs gemäß einer Ausführungsform der Erfindung und
• 2 ein schematisches Ablaufdiagramm eines Verfahrens gemäß einer Ausführungsform der Erfindung.

In the following, preferred exemplary embodiments of the invention are explained in greater detail on the basis of greatly simplified schematic representations. Show here

• 1 a schematic representation of an electrically driven tool according to an embodiment of the invention and
• 2 a schematic flow diagram of a method according to an embodiment of the invention.

The 1 shows a schematic representation of an electrically driven tool 1 according to a first embodiment of the invention. The tool 1 has an electric motor 2 on, which has a gearbox 4 a tool holder 6 drives. According to the embodiment, the tool 1 a jigsaw 1 with one in the tool holder 6 used saw blade 8th as a tool attachment 8th ,

At least one actuator 10 serves to brake the tool holder 8th , This is the actuator 10 electrically against the tool holder 8th pressed and thereby stopped or fixed.

The actuator 10 is controlled by a control unit 12 controlled and regulated. The control unit 12 is designed as a control unit and supplies the electric motor 2 with electrical energy from an energy store 14 ,

The energy storage 14 Here is a rechargeable lithium-ion battery. Alternatively or additionally, the tool 1 be directly or indirectly coupled to an energy source via a power source connection. The power source connection can also charge the energy storage 14 be used.

The control unit 12 is with two sensors 16 . 18 connected in a data-conducting manner and can evaluate the determined sensor measurement data. There is a sensor 16 as an acceleration and yaw rate or angular acceleration sensor 16 and a second sensor 18 as a capacitive proximity sensor 18 designed.

The actuator 10 can from the control unit 12 based on the sensor measurement data of the sensors 16 . 18 be controlled and accordingly also the power supply of the electric motor 2 to adjust.

Furthermore, the control unit 12 with a communication device 20 equipped, so here is a data transfer or a communication connection 21 according to a Bluetooth standard is possible. According to the embodiment, the tool communicates 1 or the control unit 12 with a smartphone 22 ,

The smartphone 22 provides sensor measurement data of an integrated acceleration sensor 24 the control unit 12 over the communication connection 21 to disposal. Thus, the tool can 1 on external sensors 24 access and increase its functionality.

In the 2 is a schematic flow diagram of a method 26 represented according to an embodiment of the invention. The procedure 26 for example, from the control unit 12 of the tool 1 be performed.

It will be in an operation or at a standstill of the tool 1 Sensor measurement data from at least one sensor 16 . 18 read out and evaluated to assess at least one safety-critical event 28.

In case of a detected safety-critical event 29 will be at least one emergency braking mode 30 for braking 33 the tool holder 6 by the at least one actuator 10 of the tool 1 executed. The comfort brake mode 32 may be definable or configurable by a user and may preferably be initiated or activated by the user. The configuration of the comfort brake mode 32 is preferably optionally carried out by the user.

Will not be a safety-critical event 31 through the control unit 12 of the tool 1 is detected, the tool holder 6 through at least one user-defined comfort braking mode 32 by the at least one actuator 10 braked 33.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19809939 A1 [0003]

Claims (13)

Electrically driven tool (1) comprising an electric motor (2) for directly or indirectly driving a tool holder (6) and a tool attachment (8) inserted into the tool holder (6), at least one actuator (10) for braking the tool holder (6), an energy storage device (14) or a power source connection for supplying electric power to the electric motor (2) and a control unit (12) for processing at least one user input, characterized in that the control unit (12) comprises at least one user - definable comfort braking mode (32) for has user-defined brakes of the tool holder (6) and at least one by the control unit (12) sensor-based activated emergency braking mode (30) for braking the tool holder (6). Electrically powered tool after Claim 1 , wherein the electrically driven tool (1) has at least one sensor (16, 18) and the control unit (12) is data-conducting connected to the at least one sensor (16, 18). Electrically powered tool after Claim 1 or 2 wherein the at least one emergency brake mode (30) is automatically controlled by the control unit (12) based on measurement data of at least one sensor (16, 18). Electrically powered tool according to one of Claims 1 to 3 wherein the at least one sensor (16, 18) is an acceleration sensor for detecting an acceleration and an acceleration direction of the tool (1). Electrically powered tool according to one of Claims 1 to 4 wherein the at least one sensor (16, 18) is an optical sensor or a Hall sensor for performing a Schnittenderkennung. Electrically powered tool according to one of Claims 1 to 5 wherein the at least one sensor (16, 18) is a tachometer for determining a speed characteristic of the electric motor (2). Electrically powered tool according to one of Claims 1 to 6 wherein the at least one sensor (16, 18) is a proximity sensor or a touch sensor. Electrically powered tool according to one of Claims 1 to 7 in that the electrically driven tool (1) has a communication device (20) connected to the control unit (12) for producing a wireless or wired communication connection (21). Electrically powered tool after Claim 8 in which at least one externally arranged sensor (24) can be coupled to the control unit (12) via the wireless or wired communication connection (21). Electrically powered tool according to one of Claims 8 or 9 In at least one function being able to be initiated by the control unit (12) via the wireless or wired communication connection (21) when the at least one emergency braking mode (30) is initiated. Electrically powered tool according to one of Claims 1 to 10 wherein the actuator (10) for braking the tool holder (6) is an electrically or mechanically driven actuator (10). Electrically powered tool according to one of Claims 1 to 11 wherein the control unit (12) is connected to a sensor system for monitoring state values of the electric motor (2), the energy store (14) and the at least one actuator (10). Method (26) for operating a tool (1) according to one of the preceding claims by a control unit (12) of the tool (1) connected in a data-conducting manner with at least one sensor (16, 18), wherein sensor measurement data is available during operation or when the tool is at a standstill of the at least one sensor (16, 18, 24) and evaluated for assessing (28) at least one safety-critical event, at least one emergency braking mode (30) for braking (33) a tool holder (6) in the event of a detected safety-critical event (29) at least one actuator (10) of the tool (1) is executed and wherein as long as no safety-critical event (31) was detected by the control unit (12) of the tool (1) the tool holder (6) is replaced by at least one user-defined comfort braking mode (32) at least one actuator (10) is braked.

Images