Handheld electric tool and method for operating a handheld electric tool

Abstract

The invention relates to a handheld electric tool, in particular a woodworking tool, comprising: a housing; a handle for positioning the electric tool relative to a workpiece; a travel unit for receiving a tool for producing a depression, in particular a hole and / or a groove, in the workpiece; a drive unit for driving the travel unit; and a pressurised-fluid dispensing device for dispensing gaseous pressurised fluid for rinsing the depression formed in the workpiece, in order to effect and / or assist with the removal of workpiece particles from the formed depression.

Description

[0001] Festool GmbH , Wertstraße 20 , 73240 Wendlingen Hand-held power tool and method for operating a hand-held power tool

[0002] The invention relates to a hand-held power tool, in particular a woodworking tool, comprising: a housing, a handle for positioning the power tool relative to a workpiece, a displacement unit for receiving a tool for machining a workpiece and a drive unit arranged in the housing for driving the displacement unit.

[0003] Handheld power tools are known from the prior art. For example, there are hand-held power tools in the form of a hand-held milling machine for milling a recess in the form of a slotted hole into a workpiece, as disclosed in DE 10 2011 103 014 A1.

[0004] When machining a workpiece, for example when producing a recess in a plate-shaped workpiece made of wood and / or composite material, workpiece particles, in particular dust and chips, are regularly produced. These can sometimes contribute to contamination of the recess, a work area or the surrounding area, which can also impair the functionality and operability of the power tool. Extraction devices designed to extract the workpiece particles that are created during machining have a limited penetration depth up to which the workpiece particles that are created or present in the recess can be captured by a suction flow. As a result, material particles remain in areas that are not captured by the suction flow, in particular in the recess.Such workpiece particles can negatively impact the machining result by inhibiting the movement of the tool and compromising the dimensional accuracy of the recess. Inhibiting the movement of the tool also poses the risk of transmitting the drive force of the drive unit to a power tool user, causing injury to the user and / or slowing down the power tool's movement relative to the workpiece, thus unnecessarily extending the machining time.

[0005] Another problem is that the workpiece particles remaining in the recess continue to be machined by the tool, thus leading to increased wear on the tool. The remaining material particles can also cause injury if a person tries to clean the machined workpiece of the workpiece particles.

[0006] Proceeding from this, the object of the present invention is to create an improved hand-held power tool of the type mentioned at the outset, which in particular overcomes at least one of the problems outlined above.

[0007] According to the invention, this object is achieved by a handheld power tool having the features specified in claim 1. Preferred and advantageous embodiments of a power tool according to the invention are specified in the subclaims.

[0008] The power tool according to the invention comprises a pressurized fluid dispensing device having an outlet region for dispensing gaseous pressurized fluid into a working area of ​​the tool during machining of the workpiece with the tool in order to flush the working area with the gaseous pressurized fluid.

[0009] The working area is understood to mean, in particular, the area in which the tool executes the movement intended for machining the workpiece, the space between the housing of the power tool and the workpiece during machining, and / or the space between the housing of the power tool and a guide unit of the power tool. Flushing with gaseous pressurized fluid removes workpiece particles from at least a portion of the working area, preventing the functionality of the power tool from being impaired.

[0010] In this context, an outlet region is understood to mean in particular at least one outlet opening through which pressure fluid can escape, wherein the outlet opening preferably has an outlet cross-sectional area.

[0011] The pressurized fluid can be dispensed continuously or intermittently during machining of the workpiece, wherein the start or end of the dispensing of pressurized fluid can be initiated by the user, for example by actuating a corresponding switch or opening / closing a valve, and / or by a control provided in the power tool.

[0012] The pressurized fluid dispensing device can be integrated into the power tool or designed as a modular, retrofittable system that can be connected to a power tool, for example by the pressurized fluid dispensing device having a frame construction that can be connected to the housing of the power tool. In particular, at least one electric motor is provided as the drive unit, which is supplied with power from a voltage source in the form of a mains connection or a rechargeable battery, preferably arranged on or in the housing. It is also possible for the drive unit to have a first electric motor, which can also be referred to as a drive motor, and at least one second electric motor, which can also be referred to as a servo motor.

[0013] The handheld power tool preferably further comprises the tool, wherein the tool is used to produce a depression, in particular a hole and / or a groove, in the workpiece and the pressurised fluid dispensing device is used to dispense the gaseous pressurised fluid into the resulting depression during the production of the depression in order to effect and / or assist the transport of workpiece particles from the resulting depression. For this purpose, the outlet region is arranged in particular such that the outlet opening is oriented in the direction of the workpiece and / or the resulting depression. Orientation of the outlet opening is understood in particular to mean the direction of the normal vector of the outlet cross-sectional area directed in the outlet direction of the pressurised fluid.The resulting depression has a base surface which is oriented essentially parallel or at an angle to a surface of the workpiece and is connected to the surface of the workpiece via a side surface which can also be formed from several surfaces. By releasing the pressurised fluid into the resulting depression, workpiece particles which are located within the resulting depression can be completely transported out of it or at least removed from the region of the depression in which the tool carries out the machining of the workpiece. In this way, the quantity of material particles which remain in the depression is reduced or the material particles are almost completely removed from the depression. The tool is preferably a milling cutter, in particular a wood milling cutter.

[0014] In a further preferred embodiment, the power tool comprises a suction device for sucking workpiece particles out of the work area. The suction device preferably comprises at least one suction nozzle which is designed for connection to a suction device, in particular in the form of a vacuum cleaner, and a suction opening. The suction opening is preferably oriented in the direction of the work area in order to suck workpiece particles located in the work area out of it. The suction opening is particularly preferably arranged opposite the outlet area so that the tool and / or the travel unit is located between the suction opening and the outlet area. By means of the suction, the workpiece particles rinsed out of the work area or transported out of the resulting depression can be transported further so that the amount of workpiece particles in the work area orin the recess and the amount of workpiece particles that enter the environment can be further reduced.

[0015] The power tool preferably further comprises a guide unit with a stop surface for contact with the workpiece, wherein the pressurised fluid dispensing device is preferably arranged on and / or in the guide unit. The guide unit is preferably connected to the housing via a linear guide which enables displacement of the housing relative to the guide unit. In this way, when the stop surface is in contact with the surface of the workpiece, the position of the tool relative to the workpiece surface can be adjusted. Alternatively, the linear guide can be fixedly connected to the housing. In this case, the position of the tool relative to the workpiece surface can be adjusted via a displacement unit provided for this purpose, in particular in the form of a CNC displacement unit. The displacement unit can be designed separately or integrated into the displacement unit or connected to it.Furthermore, the displacement unit enables linear displacement of the tool in any spatial direction relative to the workpiece surface. In this context, it can also be referred to as a 3-axis milling machine, especially a handheld one. The stop surface is preferably designed in several parts and comprises at least a first section and a second section, wherein the second section is connected to the guide unit by an angle adjustment device in order to adjust an angle between the first section and the second section. The stop surface can also be designed in the shape of a table or plate.

[0016] The stop surface preferably has a recess through which the tool for machining the workpiece extends, wherein the outlet region of the pressure fluid dispensing device is arranged in the region of the recess. The recess has an inlet edge directed towards the travel unit and an outlet edge connected to the inlet edge via a jacket surface and directed towards the workpiece, wherein the outlet region is preferably arranged in the region of the inlet edge, i.e. between the housing and the stop surface. The outlet region is thus protected from damage by the stop surface or the guide unit. For effective dispensing of pressure fluid into the resulting depression, the outlet opening or the outlet cross-sectional area can be oriented towards the outlet edge and / or the resulting depression and, for example, dispense the pressure fluid tangentially, in particular to the side wall of the depression, into the resulting depression.In other words, the outlet region of the pressure fluid dispensing device is designed such that pressure fluid is dispensed parallel to a center axis of the tool and / or to a center axis of the holder.

[0017] In a preferred embodiment of the power tool, the outlet area of ​​the pressurized-fluid dispensing device is arranged in a fixed position relative to, in, or on the guide unit. This means, in particular, that the outlet area remains fixed even during machining of the workpiece, and the distance between the outlet area and the tool does not change. The fixed arrangement enables a simple design of the pressurized-fluid dispensing device.

[0018] Preferably, the outlet region of the pressurized fluid dispensing device is arranged so as to be movable relative to, in or on the guide unit. A movable arrangement makes it possible to adjust the position of the outlet region to the tool to be used and / or to the geometry of the recess. For example, it is conceivable that the distance between the outlet region and the tool is set greater for a recess in the form of a groove than for a recess in the form of a bore. The distance of the outlet region in the vertical direction of the stop surface can also be adjusted so that the outlet region is positioned closer to the workpiece surface or further away from it during machining.

[0019] The drive unit is preferably designed to set the displacement unit in a displacement movement in order to move the tool relative to the workpiece. In this case, displacement movement is understood to mean, in particular, a movement relative to the workpiece or to the workpiece surface, the movement to the workpiece surface comprising components parallel and / or perpendicular. For example, the displacement unit has a spindle which executes a rotational movement and the displacement unit. The tool is held in the spindle and, in order to machine the workpiece, is set in a rotational movement, wherein the spindle is connected to the displacement unit in order to be displaced relative to the workpiece. The drive motor is provided to drive the spindle and the servomotor is provided to drive the displacement unit. A rotational movement is understood to mean a rotation of the tool about the central axis of the tool.

[0020] Advantageously, the outlet region is at least temporarily motion-coupled to the travel unit, so that the outlet region is set into an outlet region movement relative to the guide unit by the travel movement or a portion of the travel movement. The motion coupling between the outlet region and the tool makes it possible to minimize the distance between the outlet region and the tool in order to achieve the most effective discharge of pressurized fluid into the resulting depression without restricting the travel movement of the travel unit, in particular the component parallel to the workpiece surface.

[0021] Particularly preferably, the travel unit comprises a spindle holder which carries out the travel movement and the spindle which carries out the rotational movement, wherein the spindle is arranged at least in sections within the spindle holder.

[0022] Further preferably, the pressurised fluid dispensing device is movement-coupled to the spindle receptacle via a coupling unit, in particular a cam disk coupling. In this case, the spindle receptacle is in contact with a correspondingly designed cam section of the coupling unit during the travel movement or part of the travel movement, wherein the cam section, which is connected at least to the outlet region, can be spring-loaded in order to effect a return movement of the outlet region into an initial position. The initial position can be any desired position of the outlet region in the region of the recess, which enables pressurised fluid to be dispensed, in particular through the recess of the stop surface. The dispensing of pressurised fluid is preferably interrupted when the outlet region is temporarily arranged outside the region of the recess due to the outlet region movement.The coupling unit also enables movement coupling to be implemented for travel movements that have a complex path geometry, for example a back-and-forth oscillating movement on a circular path section.

[0023] In a further embodiment of the power tool, the outlet region has an outlet opening which opens out of the tool. The outlet opening is preferably arranged on the end face or on the circumference of the tool and is oriented parallel and / or perpendicular to a channel formed in the tool and extending in the longitudinal direction of the tool, and is fluidly connected to the latter. More preferably, the outlet opening can be arranged in a tool tip section and / or in a region different from the tool tip section, in particular in a region adjacent to the tool tip section and / or on the circumference of the tool, in particular in a chip space of the tool, wherein the tool tip section is advantageously made from a material different from a base material of the tool, in particular from a hard metal.By arranging the outlet opening in the tool, the gaseous pressurised fluid can be dispensed directly into the resulting depression. The power tool preferably further comprises a pressurised fluid source which is fluidically connected to the pressurised fluid dispensing device and serves to provide the pressurised fluid to the pressurised fluid dispensing device. For example, the pressurised fluid source can be formed by a first element of a coupling, in particular a quick-action coupling, which can be connected to a second element of the coupling arranged on a pressurised fluid line in order to provide a volume flow of pressurised fluid from the pressurised fluid line of the pressurised fluid dispensing device. For example, the pressurised fluid source can comprise an external supply unit which has a compressor or a pressurised fluid container and is fluidically connected to the pressurised fluid dispensing device, for example via a pressurised fluid line.The pressurized fluid dispensing device preferably has a quick-connect element for this purpose. The supply unit can also have a suction device that is fluidly connected to the suction device. It is advantageous to provide a pressurized fluid flow rate of at least 20 l / s, preferably at least 35 l / s, to ensure sufficient flushing of the work area and to effect and / or assist the transport of material particles from the resulting depression or the work area when the gaseous pressurized fluid is dispensed.

[0024] In an advantageous embodiment of the power tool, the pressure fluid source is arranged, in particular in a stationary manner, in or on the housing or the guide unit. One of these arrangement options improves the mobility of the power tool and machining of the workpiece can take place independently of an external supply unit. This can also be referred to as self-sufficient machining. The pressure fluid source preferably comprises a fluid reservoir. The fluid reservoir serves as a pressure fluid storage device and enables, for example, the provision of pressure fluid when the power tool is not supplied via a pressure fluid line, for example due to a temporary failure of the pressure fluid line or when the power tool is to be used at a location remote from the pressure fluid line.The fluid reservoir can already be filled with pressurized fluid or can be filled during operation by directing part of the volume flow of the pressurized fluid into the fluid reservoir. The fluid reservoir can also have a valve unit, in particular in the form of a shut-off valve and / or a pressure relief valve, in order to prevent the pressurized fluid from escaping from the fluid reservoir after it has been completely filled or to prevent further filling with pressurized fluid. It is also possible to release the pressure if the pressure of the pressurized fluid exceeds a permissible value, for example as a result of a malfunction or strong heating of the power tool or the fluid reservoir.

[0025] In a further embodiment of the power tool, the fluid reservoir is designed as a replaceable cartridge. Using the replaceable cartridge, which is filled with pressurized fluid, the power tool can be used for an extended period of time independently of a pressurized fluid line by replacing the cartridge with a new one after it has been emptied. The replaceable cartridge also enables the use of various gases as gaseous pressurized fluid. For example, a protective gas such as nitrogen or argon can be used if the material of the workpiece or the environment in which the workpiece is being machined requires this. Advantageously, the pressurized fluid source comprises a compressor. The compressor, which can be arranged in or on the housing or in or on the guide unit, enables autonomous machining of the workpiece over an extended period of time.The compressor can be designed as a separate unit with its own drive, particularly an electric motor, and its own power source. It can also be designed as an integrated unit, which is also powered by the drive unit of the power tool.

[0026] Furthermore, the power tool can comprise a barrier device configured to discharge gaseous pressurized fluid to provide a barrier fluid flow. The barrier device comprises a discharge opening having a discharge cross-sectional area, which is arranged such that a main flow direction of the barrier fluid flow runs substantially parallel to the workpiece surface. The barrier fluid flow can assist the transport of workpiece particles within the work area and thus prevent workpiece particles from leaving the work area in an uncontrolled manner.

[0027] Uncontrolled refers, in particular, to leaving the work area in the direction of the housing or in the direction of a user operating the power tool. The discharge opening is preferably oriented toward the extraction opening to further improve the transport of workpiece particles from the work area.

[0028] The above-mentioned object is also achieved by a method for operating a handheld power tool according to the invention. The method comprises the steps of: machining the workpiece with the tool in the work area, discharging the gaseous pressurized fluid into the work area of ​​the tool while machining the workpiece with the tool in order to flush the work area with the gaseous pressurized fluid.

[0029] Furthermore, the above-mentioned object is also achieved by a woodworking tool, in particular a wood milling cutter, having a channel extending along a central axis and an outlet opening fluidly connected to the channel for discharging gaseous pressurized fluid into a work area. The woodworking tool has, in particular, a first tool section, a second tool section with a tool tip section, and a pressurized fluid inlet chamber connected to the outlet opening via the channel.

[0030] The tool tip section forms the end section of the second tool section opposite the first tool section. The second tool section is designed, at least in part, for machining a wooden workpiece. In particular, the second tool section has cutting edges arranged on the circumference and extending in the longitudinal direction of the central axis. The tool tip section is designed for machining a wooden workpiece and extends, starting from an end face of the woodworking tool, along the central axis of the woodworking tool. The tool tip section can have end-face cutting edges extending in the radial direction on its end face.

[0031] The cutting edge extending in the longitudinal direction preferably runs in a spiral shape, wherein an angle resulting from the spiral shape of the cutting edge, which can also be referred to as the spiral angle, between the cutting edge and the central axis of the woodworking tool is preferably 10 ° to 15 °, particularly preferably 11 ° to 12 °, wherein the spiral angle in the region of the tool tip section can be greater, in particular by 0.5 ° to 1 ° greater, than the spiral angle in the remaining region of the second tool section. A correspondingly designed woodworking tool can also be referred to as a spiral milling cutter.

[0032] Advantageously, the tool tip section is made from a material different from a base material of the woodworking tool, in particular from a hard metal. Preferably, the woodworking tool has two and more preferably three cutting edges that are distributed at a uniform angular distance on the circumference of the woodworking tool. The end face can be formed by a surface that is oriented substantially perpendicular to the central axis of the woodworking tool and / or by a plurality of cutting edges, wherein all or some of the plurality of cutting edges may not be oriented perpendicular to the central axis of the woodworking tool.

[0033] The outlet opening is arranged on the front and / or peripheral side of the woodworking tool and is oriented parallel and / or perpendicular to the channel formed in the woodworking tool.

[0034] Preferably, the outlet opening is arranged in a region of the second tool section which is different from the tool tip section, wherein in particular the tool tip section is made from a material which is different from a base material of the woodworking tool, in particular from a hard metal. By arranging the outlet opening in the woodworking tool, the gaseous pressurized fluid can be discharged directly into the resulting depression. Furthermore, the channel can be introduced during manufacture into an area of ​​the woodworking tool which is easy to machine, while the areas of the cutting edges which are subject to high stress are made from a resistant material in the area of ​​the tool tip section.

[0035] Alternatively, the channel may be arranged in a hard metal portion of the woodworking tool. In particular, the woodworking tool may be made entirely of hard metal.

[0036] In the following, preferred embodiments of the invention are explained in more detail with reference to the attached drawing. In the drawing,

[0037] Figure 1 shows a first embodiment of a hand-held power tool according to the invention in a perspective view from behind,

[0038] Figure 2 shows a first embodiment of a hand-held power tool according to the invention in a perspective view from the front,

[0039] Figure 3 shows a movement unit of the power tool with a tool, a suction device and a first embodiment of a pressure fluid dispensing device in a side view in a sectional view,

[0040] Figure 4 shows the movement unit, the suction device and a second embodiment of a pressure fluid dispensing device in a side view in a sectional view,

[0041] Figure 5a shows an alternative movement unit of a second embodiment of the hand-held power tool in a first position, the suction device and a third embodiment of a pressurized fluid dispensing device in a side view in a sectional view,

[0042] Figure 5b shows the movement unit from Figure 5a in a second position, the suction device and the design of the pressure fluid dispensing device from Figure 5a in a side view in a sectional view,

[0043] Figure 5c shows the movement unit from Figure 5a in a third position, the suction device and the design of the pressure fluid dispensing device from Figure 5a in a side view in a sectional view,

[0044] Figure 6a shows the pressure fluid dispensing device from Figure 5a in a side view,

[0045] Figure 6b shows the pressurized fluid dispensing device from Figure 6a in a side view in a sectional view,

[0046] Figure 7 shows a section of a third embodiment of the hand-held power tool with a fourth embodiment of a pressurized fluid dispensing device in a side view in a sectional view,

[0047] Figure 8a shows a first embodiment of a tool for woodworking with an outlet area in a side view in a sectional view,

[0048] Figure 8b shows a second embodiment of a woodworking tool with an outlet region in a side view in a sectional view, Figure 8c shows a third embodiment of a woodworking tool with an outlet region in a side view in a sectional view,

[0049] Figure 9a shows a fourth embodiment of a tool for woodworking with an outlet area in a side view and

[0050] Figure 9b Sectional view along the section plane AA of the embodiment of the tool from Figure 9a in a top view.

[0051] Figures 1 and 2 show a first embodiment of a handheld power tool 1 according to the invention. The power tool 1 comprises a housing 3, a guide handle 4 and a handle 5 for positioning the power tool 1 relative to a workpiece (not shown), a drive unit 7 arranged in the housing 3, and a guide unit 9.

[0052] In the area of ​​the handle 5, an activation button 6 is arranged on an upper side of the housing 3, with which the power tool 1 can be switched on and off.

[0053] Furthermore, an adjustment element 8 is arranged on the top side of the housing 3 in the area between the activation button 6 and the guide unit 9. The guide unit 9 has a stop surface 11 with which the guide unit 9 can be brought into contact with a surface of the workpiece to be machined.

[0054] The stop surface 11 of the guide unit 9 shown is made up of several parts and comprises a first section 15 and a second section 17, the second section 17 being connected to the guide unit 9 via an angle adjustment device 19 in order to be able to set an angle between the first section 15 and the second section 17. The guide handle 4 is arranged at an end of the second section 17 facing away from the first section 15. A setting is shown in which the angle between the first section 15 and the second section 17 is 180°. The angle can preferably be set in a range from 90° to 180°. In order to fix the set angle, the angle adjustment device 19 has a first locking element 20. A lower edge 16 of the first section 15, i.e.Adjacent to the edge of the first section 15 facing away from the second section 17 is a floor stop surface 12 which is oriented substantially perpendicular to the first section 15 of the stop surface 11. A distance between an edge 18 of the second section 17 facing the first section 15 in a direction perpendicular to the floor stop surface 12, which can also be referred to as a vertical direction, is possible via a vertical guide device 22. This is particularly advantageous when the angle between the first section 15 and the second section 17 is 90° and the second section 17 is brought into contact with a surface of a workpiece to be machined, for example to machine an end face of the workpiece. A second locking element 24 is provided to determine the set distance between the edge 18 and the floor stop surface 12.

[0055] The guide unit 9 is connected to the housing 3 via a linear guide 13, which enables a displacement of the housing 3 relative to the guide unit 9. Such a displacement can also be referred to as a displacement in the longitudinal direction. A tool 21 used to produce a depression in the workpiece extends through a recess 23 formed in the first section 15 of the stop surface 11, wherein a distance between the workpiece-side end of the tool 21, which can also be referred to as a milling cutter tip, and the first section 15 of the stop surface 11 can be varied, at least during the machining of the workpiece, by the tool 21 being moved in a direction perpendicular to the first section 15 when the stop surface 11 is at least partially in contact with the workpiece.For example, for this purpose, the housing 3 is displaced along the linear guide 13 of the guide unit 9 in the direction of the stop surface 11 or in the opposite direction. The maximum distance between the workpiece-side end of the tool 21 and the first section 15 of the stop surface 11 can be specified by a depth adjustment device 14, which limits the maximum displacement along the linear guide 13.

[0056] Furthermore, a pressure fluid dispensing device 25 and a suction device 27 are arranged on the guide unit 9.

[0057] The pressurized fluid dispensing device 25 with an outlet region 29 is designed to dispense gaseous pressurized fluid into a working area of ​​the tool 21 in order to flush the working area with the gaseous pressurized fluid during machining of the workpiece or to dispense pressurized fluid into the resulting depression. At the end of the pressurized fluid dispensing device 25 facing away from the outlet region 29, as can be seen particularly in Figure 1, there is arranged a pressurized fluid source 41 which is fluidly connected to the pressurized fluid dispensing device 25 and is designed, for example, in the form of a cylindrical cartridge. A working area is understood to be the area in which the tool 21 carries out the movement intended for machining a workpiece, the space lying between the housing 3 of the power tool 1 and the workpiece during machining, and the space between the housing 3 of the power tool 1 and a guide unit 9.By flushing with gaseous pressurized fluid, workpiece particles are transported out of at least a partial section of the work area and the functionality of the power tool 1 is prevented from being impaired. The workpiece particles are transported further by the suction device 27, wherein the suction device 27 has a suction nozzle 43 for connecting the suction device 27 to a suction device, not shown, and a suction opening 45, which in the present case is arranged opposite the outlet area 29. The suction nozzle 43 arranged at an end of the suction device 27 opposite the suction opening 45 has locking elements 44 arranged on the circumference for connection to the suction device, not shown. In this way, for example, a connecting nozzle of the suction device can be locked to the suction nozzle 43.

[0058] The first embodiment of the pressure fluid dispensing device 25, a tool 21 and the suction device 27 are shown in Figure 3. The outlet region 29 of the suction device 27 is arranged in a stationary manner on the guide unit 9 in the region of an inlet edge 33 of the recess 23, wherein an outlet opening 35 of the outlet region 29 is oriented in the direction of an outlet edge 39 of the recess 23 which is connected to the inlet edge 33 via a lateral surface 37. For the fluid connection of the pressure fluid dispensing device 25 to the pressure fluid source 41, the pressure fluid dispensing device 25 has an inlet region 30 at its end opposite the outlet region 29. The inlet area 30 is fluidly connected to the outlet area 29 via a pressurized fluid channel 32. For the removal or further transport of the fluid captured or discharged by a pressurized fluid flow.on swirled workpiece particles, the suction opening 45 of the suction device 27 is oriented in the direction of the working area and is thus oriented exemplarily perpendicular to a central axis 26 of the tool 21, wherein an orientation is understood to mean the direction of a normal vector of a suction opening cross-sectional area limited by the suction opening 45.

[0059] The tool 21 is accommodated in a displacement unit 31, which is driven, at least rotationally, by the drive unit 7. To supply voltage to an electric motor of the drive unit 7, a power supply connection 47 (see Figure 1) is arranged at the rear end of the housing 3, i.e., at the end opposite the guide unit 9.

[0060] The embodiment of the pressurized fluid dispensing device 25 shown in Figure 4, whose outlet region 29 is oriented as described above, further comprises a blocking device 49. The blocking device 49 is designed to dispense gaseous pressurized fluid to provide a blocking fluid flow and comprises a dispensing opening 51 which is oriented in the direction of the suction opening 45, wherein an orientation is understood to mean the direction of a normal vector of a dispensing opening cross-sectional area delimited by the dispensing opening 51. In the embodiment shown, the blocking device 49 is connected via a further inlet region 50 to the pressurized fluid source 41 for supplying the blocking device 49 with pressurized fluid, wherein the dispensing opening 51 and the further inlet region are fluidly connected via a blocking fluid channel 52.By way of example, the blocking device 49 is integrated in the pressure fluid dispensing device 25, wherein the inlet region 30 and the further inlet region 50 open out at a common outer surface 28 of the pressure fluid dispensing device 25 and the pressure fluid channel 32 and the blocking fluid channel 52 run essentially parallel to one another.

[0061] Figures 5a, 5b and 5c show an alternative movement unit 31 and a third embodiment of the pressurised fluid dispensing device 25 of a second embodiment of the power tool 1, the third embodiment of the pressurised fluid dispensing device 25 being shown in isolation in Figures 6a and 6b. The pressurised fluid dispensing device 25 has the outlet region 29 and the inlet region 30, which are fluidly connected via the pressurised fluid channel 32. In this embodiment, the inlet region 30 is designed as a plug-in connector that can be connected to a pressurised fluid hose (not shown) in order to connect the pressurised fluid dispensing device 25 to an external pressurised fluid source (not shown), for example in the form of a compressor, for supplying the pressurised fluid dispensing device 25 with pressurised fluid. The suction device 27 is designed as previously described.

[0062] In this embodiment of the power tool 1, the drive unit 7 is designed to set the travel unit 31 in a travel movement in order to move the tool 21 relative to the workpiece. The travel unit 31 comprises a spindle holder 53 which carries out the travel movement and a spindle 55 which is accommodated in sections in the spindle holder 53 and carries out a rotational movement. In the present exemplary embodiment, the travel movement takes place periodically between the first position of the travel unit 31 shown in Figure 5a and the third position of the travel unit 31 shown in Figure 5c, the second position of the travel unit 31 shown in Figure 5b being passed through during the travel movement. A travel movement is defined as a movement relative to the workpiece orto the workpiece surface, wherein the movement to the workpiece surface comprises parallel and / or perpendicular components, wherein a movement amplitude parallel to the workpiece surface can be varied by means of the adjusting element 8.

[0063] In order to minimize a distance oriented parallel to the workpiece surface between the outlet area 29 and the tool 21 and to effect the most effective possible discharge of pressure fluid into the resulting depression, the outlet area 29 is motion-coupled to the travel unit 31, so that the outlet area 29 is displaced into an outlet area movement relative to the guide unit 9 by the travel movement.

[0064] For the movement coupling between the outlet region 29 and the displacement unit 31, the pressurized fluid dispensing device 25 has a coupling unit 57 having a curved section 59, wherein the spindle receptacle 53 is in contact with the curved section 59 of the coupling unit 57. By way of example, the curved section 59 is flat, but can have further profiles tailored to the displacement movement of the displacement unit 31.

[0065] The coupling unit 57 shown is designed in several parts and comprises a bearing element 61, which is arranged in a stationary manner in or on the guide unit 9, and a displacement element 63, which is connected to the bearing element 61 via guide bars 65, which enable a displacement of the displacement element 63 relative to the bearing element 61. The guide bars 65 are mounted in bearing sleeves 66 in the displacement element 63. In order to set the outlet area 29 into an outlet area movement relative to the guide unit 9 by the displacement movement, the outlet area 29 is fixedly connected to the displacement element 63. Springs 67, which enable the displacement element 63 to be returned to an initial position, are arranged between the bearing element 61 and the displacement element 63.If the spindle holder 53 executes a movement directed toward the bearing element 61 up to the first position shown in Figure 5a, the displacement element 63 is displaced along the guide rails 65 in the direction of the bearing element 61. If the spindle holder 53, after reaching the first position, executes the opposite movement toward the second (Figure 5b) or third (Figure 5c) position, the displacement element 63 is displaced away from the bearing element 61 by the springs 67 along the guide rails 65.

[0066] The coupling unit 57 contains limit switches (not shown) that are signal-linked to a control system (not shown) provided in the power tool 1. Upon reaching the first position (Figure 5a), i.e., upon activation of the limit switches, the control system can initiate the termination of the pressure fluid dispensing. Pressure fluid dispensing restarts when the spindle holder 53 leaves the first position, so that the limit switches no longer activate.

[0067] In a third embodiment of the power tool 1, shown in section in Figure 7, the outlet region 29 has an outlet opening 35 leading from the tool 21, so that pressurized fluid can be discharged from the tool 21 directly into the resulting recess in the workpiece to be machined. For the fluidic connection of the outlet opening 35 to the pressurized fluid source 41 or to a pressurized fluid line 69 connected to the pressurized fluid source 41, a channel 71, 73 is formed in each of the spindle 55 and the tool 21, wherein the channels 71, 73 run along the axial extent of the spindle 55 and the tool 21, respectively.

[0068] Figures 8a, 8b and 8c show a section through various embodiments of a tool 21 designed as a woodworking tool, more precisely as a wood milling cutter, for use with the embodiment of the power tool 1 shown in Figure 7. The illustrated embodiments of the woodworking tool each have two cutting edges 70 with corresponding chip spaces 79, with only one cutting edge 70 being visible in Figures 8a, 8b and 8c.

[0069] The tool 21 shown in Figure 8a has a first tool section 74, which is essentially cylindrical, and a second tool section 75 with a smaller diameter, which adjoins the first tool section 74 and is, for example, partially cylindrical. On the area of ​​the second tool section 75 opposite the first tool section 74, a tool tip section 76 is formed which extends as far as an end face 77 of the tool 21. The channel 73 of the tool 21 connects a pressure fluid inlet chamber 78 of the tool 21 to the outlet opening 35. To connect the tool 21 to the spindle 55, the pressure fluid inlet chamber 78 has, for example, an internal thread on its inside, the spindle 55 having an external thread corresponding to this internal thread.

[0070] In the exemplary embodiment shown in Figure 8a, the outlet opening 35 is arranged in the end face 77 of the tool 21. The channel 73 therefore extends in a straight line from the pressure fluid inlet space 78 to the outlet opening 35. In the exemplary embodiment of the tool 21 shown in Figure 8b, the outlet opening 35 opens out of the tool 21 on the circumference. The channel 73 has a first channel section 80 arranged parallel to a central axis 26 of the tool 21 and a second channel section 81 oriented perpendicular to the first channel section 80, which second channel section 81 fluidly connects the first channel section 80 to outlet openings 35. In this embodiment, the pressure fluid is discharged into chip spaces 79 of the tool 21 perpendicular to the central axis 26 of the tool 21. In the present embodiment, an outlet opening 35 is arranged in each chip space 79.

[0071] Figure 8c shows a further embodiment of the tool 21, wherein the tool 21 has outlet openings 35 which are arranged in chip spaces 79 of the tool 21. In the present exemplary embodiment, an outlet opening 35 opens into each chip space 79, wherein the outlet openings 35 are connected to one another and to a first channel section 80 via channel sections 82. The outlet openings 35 are oriented such that the respective normal vector of an outlet opening cross-sectional area delimited by the respective outlet opening 35 has a component perpendicular to the central axis 26 of the tool 21 and a component parallel to the central axis 26 of the tool 21.

[0072] Figures 9a and 9b show a further embodiment of the tool 21 for use with the embodiment of the power tool 1 shown in Figure 7. In this embodiment, two cutting edges 70 are formed which extend over a substantial region of the second tool section 75. In this embodiment, the first tool section 74 and the second tool section 75 are made of a metallic base material and the tool tip section 76 is made of hard metal. Outlet openings 35, which are formed in a region of the second tool section 75 consisting of the base material, each open into one of the chip spaces 79. A spiral angle α formed between the cutting edge 70 and the central axis 26 is constant in the embodiment of the tool 21 shown over the entire extension of the cutting edges 70 and is, for example, 11.5°.The chip spaces 79 are formed on the second tool section 75 corresponding to the cutting edges 70 and enable efficient chip removal from the workpiece to be machined.

Claims

Claims 1. Hand-held power tool (1), in particular a woodworking tool, comprising: a housing (3), a handle (5) for positioning the power tool relative to a workpiece, a travel unit (31) for receiving a tool (21) for machining a workpiece, a drive unit (7) arranged in the housing (3) for driving the displacement unit (31), and a pressurized fluid dispensing device (25) with an outlet region (29) for dispensing gaseous pressurized fluid into a working region of the tool (21) during machining of the workpiece with the tool (21) in order to flush the working region with the gaseous pressurized fluid.

2. Hand-held power tool according to claim 1, further comprising the tool (21), wherein the tool (21) serves to produce a depression, in particular a hole and / or a groove, in the workpiece and the pressurized fluid dispensing device (25) serves to dispense the gaseous pressurized fluid into the resulting depression during the production of the depression in order to effect and / or assist the transport of workpiece particles from the resulting depression.

3. Power tool according to claim 1 or 2, further comprising a suction device (27) for sucking workpiece particles out of the work area.

4. Power tool according to claim 1 or 2, further comprising a guide unit (9) with a stop surface (11) for Attachment to the workpiece, wherein the pressure fluid dispensing device (25) is arranged on and / or in the guide unit (9).

5. Power tool according to claim 4, wherein the stop surface (11) has a recess (23) through which the tool (21) extends for machining the workpiece, wherein the outlet region (29) of the compressed fluid dispensing device (25) is arranged in the region of the recess (23).

6. Power tool according to claim 5, wherein the outlet region (29) of the pressure fluid dispensing device (25) is arranged stationary relative to, in or on the guide unit (9).

7. Power tool according to claim 5, wherein the outlet region (29) of the pressure fluid dispensing device (25) is arranged to be movable relative to, in or on the guide unit (9).

8. Power tool according to claim 7, wherein the drive unit (7) is designed to set the displacement unit (31) into a displacement movement in order to move the tool (21) relative to the workpiece.

9. Power tool according to claim 7 or 8, wherein the outlet region (29) is at least temporarily coupled in movement to the displacement unit (31), so that the outlet region (29) is displaced into an outlet region movement relative to the guide unit by the displacement movement.

10. Power tool according to one of the preceding claims, wherein the displacement unit (31) is a Spindle holder (53) and a spindle (55) performing a rotational movement, wherein the spindle (55) is arranged at least in sections within the spindle holder (53).

11. Power tool according to one of claims 7 to 10, wherein the pressurized fluid dispensing device (25) is coupled in terms of movement to the spindle holder (53) via a coupling unit (57), in particular a cam coupling.

12. Power tool according to one of claims 1 to 3, wherein the outlet region (29) has an outlet opening (35) which opens out of the tool (21), in particular out of a tool tip section (76).

13. Power tool according to claim 12, wherein the tool (21) is a woodworking tool, in particular a wood milling cutter.

14. Power tool according to any preceding claim, further comprising a pressurized fluid source (41) fluidly connected to the pressurized fluid dispensing device (25) and serving to provide the pressurized fluid to the pressurized fluid dispensing device.

15. Power tool according to claim 14, wherein the pressure fluid source (41) is arranged, in particular stationary, in or on the housing (3) or the guide unit (9).

16. Power tool according to claim 14 or 15, wherein the pressurized fluid source (41) comprises a fluid reservoir.

17. Power tool according to claim 16, wherein the fluid reservoir is designed as a replaceable cartridge.

18. Power tool according to one of claims 14 to 17, wherein the pressurized fluid source (41) comprises a compressor.

19. Power tool according to one of the preceding claims, wherein the outlet region (29) is arranged such that an outlet opening (35) is oriented in the direction of the workpiece and / or a resulting depression.

20. A method for operating a hand-held power tool (1) according to any one of the preceding claims, comprising the steps: Machining the workpiece with the tool (21) in the working area, Dispensing the gaseous pressure fluid into the work area during machining of the workpiece with the tool (21) in order to flush the work area with the gaseous pressure fluid.

21. Tool (21) for woodworking, in particular a wood milling cutter, with a channel (73) extending along a central axis (26) and an outlet opening (35) fluidically connected to the channel (73) for discharging gaseous pressurized fluid into a working area.

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