Hand-held power tool, in particular jigsaw with blower attachment

Abstract

hand-held power tool (10), in particular jigsaw, for producing a cut (115) in a feed direction (V) in a workpiece (15), - comprising a tool holder (40), a cutting area (110), a housing (20), a support device (35) for supporting the hand-held power tool (10) on the workpiece to be machined (15), in particular a base plate (50), and a blowing device (30), - wherein the housing (20) has a housing bottom (135) and a housing front (125), - wherein the tool holder (40) is designed to accommodate an insert tool (80), in particular a saw blade (85), along a mounting axis (75), - wherein the support device (35) can be placed against the workpiece (15) in a guide plane (55), - wherein the receiving axis (75) intersects the guide plane (55) in a cutting area (110), - wherein the blowing device (30) has a first air channel (160) which terminates in a first channel opening (205) which is arranged on the underside of the housing (135) in the feed direction (V) in front of the tool holder (40) and is designed to inject an airflow (330) into the cutting area (110), characterized in that - the blowing device (30) further comprises a conveying unit (175) for generating the airflow and a second air channel (165), - wherein the blowing device (30) has a valve (170) which is switchable between a first valve position and a second valve position, - wherein the valve (170) is fluidically connected on the inlet side to the conveying unit (175) and on the outlet side to the first air duct (160) and the second air duct (165), - and wherein in the first valve position a fluidic connection is established between the conveying unit (175) and the first air duct (160) and in the second valve position a fluidic connection is established between the conveying unit (175) and the second air duct (165).

Description

[0001] The invention relates to a hand-held power tool, in particular a jigsaw with a blowing device according to claim 1. State of the art

[0002] From DE 10 338 602 B3, a motor-driven saw is known, comprising a housing, a cutting area, and a motor cooled by a fan. The fan draws air into the housing via an air intake duct system and, after passing the motor, expels it from the housing via an exhaust duct system. In the cutting area, a saw blade attached to the saw cuts a guide plane defined by a guide device, within which the saw can be positioned against a workpiece. The exhaust duct system has an exhaust outlet for supplying air to the cutting area. The exhaust duct system also has a second exhaust outlet on an end face of the housing, located above the cutting area and directed towards the guide plane, over which a curtain of blown air extending transversely to the cutting plane can be stretched. Other solutions for chip removal in hand-held power tools are also known.Patent applications US 2003 / 0121389A1 and US 4870755A each disclose a frontal air blowing system for cleaning the cutting area. Patent application DE 102008041094A1 shows an alternative device for chip removal. Patent application WO 2008 / 000544A1 describes the routing of an air duct around a gearbox, and patent application EP 0221652A1 discloses a valve for switching between a blowing and a suction function.

[0003] The purpose of the invention is to provide an improved hand-held power tool. Disclosure of the invention

[0004] This task is accomplished using a hand-held power tool according to claim 1. Advantageous embodiments are specified in the dependent claims.

[0005] It was recognized that an improved handheld power tool, in particular an improved jigsaw, for producing a feed-directed cut in a workpiece can be provided by the handheld power tool comprising a tool holder, a cutting area, a housing, a support device for supporting the handheld power tool on the workpiece to be machined, in particular a base plate, and a blowing device. The housing has a bottom and an end face. The tool holder is configured to accommodate an insert tool, in particular a saw blade, along a mounting axis. The support device can be placed against the workpiece in a guide plane. The mounting axis intersects the guide plane in a cutting area. The blowing device has a first air channel and is configured to provide an airflow.A first air duct opening is located on the underside of the housing, on a side opposite the cutting area and in the feed direction upstream of the tool holder. The first air duct has a subsection adjoining this first opening. This subsection is arranged perpendicular to or inclined to the guide plane. The first air duct opening is designed to direct the airflow into the cutting area.

[0006] This design has the advantage that any sawdust produced during sawing, which might obstruct the view of the cutting line on the workpiece, is reliably removed from the workpiece by the airflow. Furthermore, it prevents the airflow from being disrupted when it enters the cutting area, for example, by the cutting tool itself.

[0007] An alternative embodiment of an improved hand-held power tool can be provided by the hand-held power tool having a blowing device, wherein the blowing device has a first air duct and a valve and is configured to provide an airflow, wherein the valve has a valve housing and a valve body rotatably mounted about the axis of rotation between a first valve position and a second valve position, the valve body having an annular section, the annular section having a first valve opening and the valve housing having a first valve duct, wherein in the first valve position the valve duct and the first valve opening have an overlap, and wherein the first valve duct is connected downstream to the first air duct.

[0008] According to the invention, the blowing device comprises at least a second air channel and a conveying unit, the conveying unit being configured to convey the airflow during operation. The conveying unit is fluidically connected to the second air channel, the second air channel opening at a distance from the cutting area at a second channel opening. The second channel opening is arranged on a side of the tool holder facing away from the housing end face. The second air channel is configured to guide at least a portion of a further airflow towards the cutting area during operation of the hand-held power tool. By providing the two air channels, reliable blowing off of the chips can be ensured.

[0009] According to the invention, the blowing device further comprises a valve, wherein the valve has a first valve position and a second valve position. The valve is fluidically connected to the conveying unit on the inlet side. The valve is fluidically connected to the first air channel and the second air channel on the outlet side. In the first valve position, the first air channel is fluidly connected to the conveying unit. In the second valve position, the second air channel is fluidly connected to the conveying unit. This design has the advantage that, depending on the application of the hand-held power tool, the user can determine the respective blowing behavior of the hand-held power tool by means of the valve.

[0010] In a further embodiment, in the first valve position, the first air channel is fluidically connected to the conveying unit, and the second air channel is fluidically separated from the conveying unit. In the second valve position, the second air channel is fluidically connected to the conveying unit, and the first

[0011] The air duct is fluidically separated from the conveying unit. This allows for a particularly high airflow for blowing off material, either forward via the second air duct or for blowing off the chips in all directions, but from the front.

[0012] In a further embodiment, the valve has a third valve position. In this third position, the first and second air channels are fluidically isolated from the conveying unit. This prevents (temporary) blowing of the chips. Particularly when the hand-held power tool is in an unfavorable position, this prevents the chips from being blown towards the user.

[0013] In another embodiment, the blowing device has a vent channel. The vent channel is connected to the valve at one end and opens into the area surrounding the power tool at the other end. In the third valve position, the vent channel is fluidically connected to the conveying unit. This ensures reliable cooling of the power tool's drive even when the blowing action is deactivated.

[0014] In a further embodiment, the conveying unit has a fan wheel mounted non-rotatably on a drive shaft of the drive motor. The valve comprises a valve housing and a valve body rotatably mounted about the axis of rotation, with an annular section. The annular section surrounds the fan wheel radially on its outer side. The annular section has a first valve opening and a second valve opening arranged circumferentially offset from the first valve opening. In the first valve position, the first valve opening overlaps with the first valve channel, and the annular section closes the second valve channel. The first valve channel and the first air channel, as well as the second valve channel and the second air channel, are fluidically connected. In the second valve position, the annular section is arranged circumferentially rotated about the axis of rotation relative to the first valve position.In the second valve position, the first valve opening is spaced apart from the first valve channel, and the annular section closes the first valve channel. In the second valve position, the second valve opening has a second overlap with the second valve channel. This design has the advantage that the hand-held power tool for both the valve and the conveying unit can be made particularly compact. In particular, the number of components in the valve is very low.

[0015] In another embodiment, the valve housing circumferentially encloses the ring section with an inner circumferential side and rotatably mounts the ring section about the axis of rotation. The valve body has at least one actuating lever extending radially outwards. The actuating lever is connected to the ring section. The housing has at least one recess. The recess opens onto an outer circumferential side of the hand tool. The actuating lever extends through the associated recess. This design has the advantage that the valve can be switched particularly easily.

[0016] In another embodiment, the hand-held power tool has a gearbox. The gearbox is connected to the drive motor on the input side and to the tool holder on the output side. The gearbox is designed to convert a rotary motion of the drive motor into an oscillating motion of the tool holder. The first air duct is routed at least partially around the gearbox on a side facing away from the cutting area.

[0017] In a further embodiment, the hand-held power tool has a saw blade with a saw section and a shank connected to the saw section. The shank engages in the tool holder and is connected to it. The saw section is plate-shaped, and at least one row of saw teeth is arranged on only one side surface. The first air channel is designed to direct the airflow on a side facing the row of teeth, either substantially parallel to the saw section or inclined at an angle to the row of teeth. This design has the advantage that any chips that may be located between the teeth can be reliably removed by means of the airflow, thus enabling a particularly high cutting performance.

[0018] In another embodiment, the partial area is arranged at an angle of 0° to 20° to the receiving area.

[0019] The invention is explained in more detail below with the aid of figures. These show: Fig. 1 a longitudinal section through a hand-held machine tool according to a first embodiment and a workpiece; Fig. 2 a top view of the in Fig. 1 hand-held power tool shown; Fig. 3 a perspective view of a valve body of a valve that is in the Fig. 1 and Fig. 2 hand-held power tools shown; Fig. 4 a sectional view along a Fig. 2 shown section plane AA through the in the Fig. 1 and Fig. 2 hand-held power tools shown; Fig. 5 a sectional view along the in Fig. 2 section plane AA shown through the in Fig. 2 hand-held power tools shown; Fig. 6 and Fig. 7 a sectional view along the in Fig. 2 section plane AA shown through a hand-held power tool according to a second embodiment; Fig. 8 a side view of a hand-held power tool according to a third embodiment; Fig. 9 a perspective view of a valve body of the in Fig. 8 hand-held power tool shown; and Fig. 10 a sectional view through the in Fig. 8 hand-held power tool shown 10 along a in Fig. Section plane BB shown in section 8.

[0020] The following figures refer to a coordinate system for ease of understanding. This coordinate system is an example of a right-handed system and has an x-axis (longitudinal direction), a y-axis (transverse direction), and a z-axis (vertical direction).

[0021] Fig. Figure 1 shows a longitudinal section through a hand-held machine tool 10 according to a first embodiment and a workpiece 15.

[0022] The hand-held power tool 10 comprises a housing 20, a drive unit 25, a blower 30, a support unit 35, and a tool holder 40. In this embodiment, the hand-held power tool 10 is configured as a jigsaw by way of example. Of course, other configurations of the hand-held power tool 10, for example as a reciprocating saw, are also conceivable.

[0023] In this embodiment, the workpiece 15 is exemplarily designed as a plate and has an exemplarily flat workpiece surface 45. The support device 35 has a base plate 50. The base plate 50 has a guide plane 55 on a side facing the workpiece 15. The guide plane 55 extends in an xy-plane. During operation of the hand-held power tool 10, the support device 35 with the guide plane 55 rests flat against the workpiece surface 45.

[0024] The drive device 25 comprises a drive motor 60 with a drive shaft 65 and a gearbox 70. The gearbox 70 is non-rotatably connected to the drive shaft 65 at its input. The drive motor 60 is designed as an electric machine, in particular as a brushless electric machine. Alternatively, the drive motor 60 can also be designed as a brushed motor.

[0025] The drive motor 60 can be electrically connected to an electrical power supply (not shown), for example, a mains connection or an electrical energy storage device, in particular a battery. Additionally, the drive device 25 can have a control unit (not shown) for controlling the drive motor 60.

[0026] The gearbox 70 is connected to the tool holder 40 on the output side. The gearbox 70 is configured to convert a rotary motion of the drive motor 60, which is supplied to the gearbox 70 via the drive shaft 65, into a repetitive oscillating lifting and lowering motion essentially perpendicular or slightly inclined to the guide plane 55 for driving the tool holder 40.

[0027] The tool holder 40 has a receiving axis 75. The receiving axis 75 is arranged essentially perpendicular or slightly inclined to the guide plane 55. During operation of the hand-held power tool 10, a tool 80 is inserted into the tool holder 40. In this embodiment, the tool 80 is, by way of example, a saw blade 85 with a saw section 90 and a shank 95 connected to the saw section 90. The saw blade 85 engages the tool holder 40 with its shank 95. A connecting element (not shown) of the tool holder 40 secures the shank 95 in the tool holder 40. The saw blade 85 thus extends essentially along the receiving axis 75. The saw section 90 can be plate-shaped and extends essentially in an xz-plane.The saw section 90 has at least one row of teeth 100 of saw teeth 105 exclusively on a single side surface that extends essentially in a yz plane. Of course, several rows of teeth 100 can also be provided.

[0028] The mounting axis 75 intersects the guide plane 55 in a cutting area 110. During operation of the hand-held power tool 10, the saw blade 85 is moved in an oscillating, up-and-down motion (primarily in the z-direction) by the movement of the tool holder 40 and the coupling of the shank 95 to the tool holder 40. When the saw section 90 engages the workpiece 15, a cut 115 is made in the workpiece 15. The resulting chips are lifted upwards from the cutting area 110 by the tooth row 100. During this process, the hand-held power tool 10 moves in the feed direction V. The feed direction V runs parallel to the x-axis, but in the opposite direction. In the feed direction V, the tooth row 100 is located at the front and the drive motor 60 at the rear.

[0029] The housing 20 internally defines an interior space 120. The drive device 25 is arranged within this interior space 120. The housing 20 has a first end face 125 and a second end face 130. The first end face 125 is located at the front in the feed direction V, while the second end face 130 is set back in the feed direction V at the rear of the housing 20.

[0030] Furthermore, the housing 20 has a lower housing surface 135. In a first section 140, which directly adjoins the first housing end face 125 in the x-direction, the lower housing surface 135 is arranged at a distance from the base plate 50. In the first section 140, an opening 145 is also provided in the housing 20, wherein the opening 145 passes through the tool holder 40 and / or – depending on the operating state of the hand-held power tool 10 – through the insert tool 80.

[0031] A second section 150 of the housing underside 135, extending in the x-direction to the first section 140, is connected to the base plate 50. The second section 150 is located on the side of the first section 140 facing the second housing end face 130.

[0032] The hand-held power tool 10 can additionally have a guide device 155, for example, a roller guide. The guide device 155 is attached to the second section 150 on the side of the tool holder 40 and the insert tool 80 facing away from the first housing end face 125. The guide device 155 supports the insert tool 80 on the rear side in the feed direction, on a side facing away from the tooth row 100, so that bending stress on the insert tool 80 about the y-axis is reduced. This results in a reliable cut 115 in the workpiece 15.

[0033] The blowing device 30 comprises a first air duct 160, a second air duct 165, a valve 170, a conveying unit 175, and an intake unit 180. The intake unit 180 can have one or more intake channels 190, 195. The intake unit 180 has, by way of example, an intake opening 185 provided on the second housing end face 130. A first intake channel 190 of the intake unit 180 connects to the intake opening 185 and is fluidically connected to the drive motor 60 on the side opposite the intake opening 185. Additionally, the intake unit 180 can have a second intake channel 195, wherein the second intake channel 195 fluidically connects an end face of the drive motor 60 facing the first housing end face 125 to an inlet side of the conveying unit 175.

[0034] The conveying unit 175 is fluidically connected to the valve 170 on the downstream side. On the outlet side, the valve 170 is fluidically connected to the first air duct 160 and the second air duct 165.

[0035] The first intake duct 190, the second intake duct 195, the first air duct 160, and the second air duct 165 are bounded by the housing 20. At least the first air duct 160 and the second air duct 165 are essentially fluid-tight from the housing interior 120.

[0036] The first air duct 160 follows the contour of the housing top 200 of the housing 20 from the valve 170 towards the first housing end face 125. The first air duct 160 is routed around the top of the gearbox 70 on a side of the gearbox 70 opposite the section 110. The first air duct 160 is located essentially in the center of the housing 20 with respect to its maximum transverse extent. At the first housing end face 125, the first air duct 160 leads downwards towards the base plate 50. In the first section 140 of the housing bottom 135, the first air duct 160 opens into the housing bottom 135 at a first duct opening 205.

[0037] The first channel opening 205 is arranged opposite the guide plane 55 in the z-direction. Directly adjacent to the first channel opening 205 is a first subsection 210 of the first air duct 160. The first subsection 210, the tool holder 40, and a rotary axis 213, around which the drive shaft 65 rotates, are in a common plane, which is in Fig. The common plane is arranged as an xz-plane. The common plane is arranged perpendicular to the guide plane 55. Furthermore, the receiving axis 75 also extends in the common plane. By way of example, the first sub-section 210 is inclined obliquely backwards to the receiving axis 75, preferably at an angle of 0° to 20° in the direction of the cutting area 110. The distance of the first sub-section 110 to the first housing end face 125 decreases with increasing height (z-direction) relative to the cutting area 110.

[0038] The second air duct 165 runs along the underside of the drive device 25 and extends between the valve 170 and the underside of the housing 135. The second air duct 165 opens into the underside of the housing 135 at a second duct opening 211 on the side of the second housing end face 130 of the second section 150 of the housing 20. The second air duct 165 has a second subsection 212 adjacent to the second duct opening 211, which is inclined obliquely to the rear. The distance between the second subsection 212 and the second housing end face 130 decreases with increasing height.

[0039] Fig. 2 shows a top view of the in Fig. 1 hand-held power tool shown 10.

[0040] The housing 20 can additionally have a handle 220. The handle is located on the top of the housing 200. The handle 220 is set back relative to the gearbox 70 in the feed direction V. The handle 220 serves to enable a user of the hand-held power tool 10 to grip and position the tool particularly well. The handle 220 is located in the x-direction between the second housing end face 130 and the gearbox 70. In the z-direction, the handle 220 is positioned, for example, above the drive motor 60.

[0041] The housing 20 has a first housing side surface 225 on an outer circumferential side of the housing 20 and a second housing side surface 230 arranged transversely opposite the first housing side surface 225. The housing side surfaces 225, 230 are axially symmetrical, for example about an xz-plane.

[0042] Fig. Figure 3 shows a perspective view of a valve body 235 of the valve 170.

[0043] The valve body 235 has an annular section 240 and at least one actuating lever 245, 250. In this embodiment, the valve body 235 of the valve 170 has a first actuating lever 245 and a second actuating lever 250 arranged circumferentially, preferably by 180°, relative to the first actuating lever 245. The actuating levers 245, 250 are, by way of example, plate-shaped. The first actuating lever 245 and the second actuating lever 250 are attached radially to the outside of an outer circumferential side 255 of the annular section 240. It is particularly advantageous if the valve body 235 is formed in one piece and from a single material using an injection molding process, especially plastic injection molding.

[0044] In the radial direction with respect to the axis of rotation 213, the first actuating lever 245 and the second actuating lever 250 have the same extent. Likewise, the cross-section of the first actuating lever 245 and the second actuating lever 250 is, by way of example, identical. In the axial direction with respect to the axis of rotation 213, the first actuating lever 245 and the second actuating lever 250 are, by way of example, narrower than the ring section 240.

[0045] In the ring section 240, at least one valve opening 260 and a second valve opening 265 arranged circumferentially to the first valve opening 260 are arranged. The first valve opening 260 has, by way of example, a rectangular opening cross-section and is in Fig. 3 arranged on the top. On the bottom in Fig. In section 240 of the ring, the second valve opening 265 is arranged as an example. The first valve opening 260 and the second valve opening 265 have the same opening cross-section.

[0046] Fig. Figure 4 shows a sectional view along a [unclear] in Fig. 2 shown section plane AA through the hand-held machine tool 10.

[0047] The housing 20, for example, has two housing shells 275 that are mirror images of each other. The valve 170 has a valve housing 270. In this embodiment, the valve housing 270 is formed in one piece and of the same material as the housing 20. The valve housing 270 can also be divided into two valve shells, each valve shell being connected to a housing shell 275.

[0048] The valve housing 270 is fluidically connected at its outlet to the first air channel 160 and to the second air channel 165. In this embodiment, the first air channel 160 opens into the valve housing 270 from the top, and the second air channel 165 opens into the valve housing 270 from the bottom. The valve housing 270 circumferentially surrounds the annular section 240 of the valve body 235 with an inner circumferential side 276. The inner circumferential side 276 extends in a circular path around the axis of rotation 213. The annular section 240 is also cylindrical around the axis of rotation 213. The inner circumferential side 276, in operative connection with the outer circumferential side 255, rotatably supports the valve body 235 about the axis of rotation 213. Furthermore, the valve housing 270 determines the position of the valve body 235 in the axial direction.

[0049] The housing 20 and the valve housing 270 each have at least one recess, preferably a first recess 280 and a second recess 285. The first recess 280 is designed as a through-opening and extends from the inner circumferential side 276 outwards to the first housing side surface 225. The second recess 285 is arranged transversely, for example, directly opposite the first recess 280 and is designed identically to the first recess 280. The recesses 280, 285 are slot-shaped and extend, for example, over an angle segment of 36°.

[0050] The second recess 285 extends from the inner circumferential side 276 outwards to the second housing side surface 230. The first recess 280 is penetrated by the first actuating lever 245 and the second recess 285 by the second actuating lever 250, with the first actuating lever 245 projecting beyond the first housing side surface 225 and the second actuating lever 250 projecting beyond the second housing side surface 230. Alternatively, to the one described in Fig. In the embodiment shown in 4, it is also conceivable that only one recess 280, 285 is provided on the housing 20 and the valve housing 270, but then only one actuating lever 245, 250 is provided.

[0051] Valve 170 has a first valve position and at least one second valve position. Fig. Figure 4 shows the valve 170 in a first valve position. In the first valve position, the first valve opening 260 has a first overlap with a first valve channel 290 of the valve housing 270, which is fluidically connected to the first air channel 160. The first valve channel 290 extends radially outward from the inner circumferential side 276 and is offset circumferentially from the recess 280, 285. The first air channel 160 is connected to the first valve channel 290. The annular section 240 closes a second valve channel 295 of the valve housing 270, so that the second air channel 165, which is fluidically connected to the second valve channel 295 on the outlet side, is fluidically sealed. The second valve channel 295 of the valve housing 270 extends radially outward from the inner circumferential side 276. The second air duct 165 is connected to the second valve duct 295.

[0052] During operation of the hand-held power tool 10, the drive motor 60 is activated, causing the drive shaft 65 to rotate about the axis of rotation 213. The conveying unit 175 can have a fan wheel 300, which is fixedly mounted axially on the drive shaft 65 between the gearbox 70 and the drive motor 60. The fan wheel 300 is, by way of example, designed as a radial compressor wheel. The fan wheel 300 is circumferentially enclosed by the ring section 240. This allows for a particularly compact design of the valve 170 and the conveying unit 175. In particular, this design provides a fluidic connection between the valve 170 and the conveying unit 175 at the inlet side, without a channel.

[0053] During operation of the drive motor 60, the fan wheel 300 draws air in through the intake opening 185 (see below). Fig. 1) Air 325 is drawn from the environment 305 of the hand-held power tool 10. The air 325 is then introduced into the drive motor 60 via the first intake duct 190. The drawn-in air 325 flows through the drive motor 60 and cools it in the process. The heated air 325 is drawn through the second intake duct 195 towards the fan wheel 300. Depending on the position of the valve 170, the fan wheel 300 further conveys the air 325.

[0054] In the first valve position (see Fig. 4) The fan wheel 300 conveys the air 325 through the first valve opening 260 and the first valve channel 290 into the first air channel 160. The air 325 is directed past the gearbox 70 above via the first air channel 160. The air 325 then flows downwards, parallel to the first housing end face 125, in the direction of the cutting area 110. Before the air 325 exits through the first channel opening 205 towards the cutting area 110, the first sub-section 210 defines a flow direction for the air 325 after exiting the first channel opening 205. Due to the obliquely rearward orientation of the first sub-section 210, the air 325 is injected into the cutting area 110 at an angle of 0° to 20° via the first channel opening 205.

[0055] By injecting air 325 into the cutting area 110, a concentrated airflow 330 is introduced into a small area of ​​the cutting area 110 (cf. Fig. 1) This results in an airflow 330 with a particularly high flow velocity, allowing the chips to be blown off over a particularly long distance. Furthermore, it ensures that the chips produced during the creation of the cut 115 are blown off from the cutting area 110 even at high feed rates in the feed direction V. This has the advantage that the user has a clear view of the area in front of the cutting tool 80 when working with the hand-held power tool 10.

[0056] Furthermore, the air 325 injected into the cutting area 110 supports the removal of the chip material from the individual saw teeth 105 or from a tooth gap between the saw teeth 105, so that a very good cleaning effect of the insert tool 80 is achieved and an unwanted filling of the tooth row 100 with chip material can be avoided.

[0057] Furthermore, it is advantageous if the air 325 is injected obliquely backwards into the cutting area 110, so that if a dust extraction device (in) is attached to the hand-held power tool 10 Fig. 1 (not shown) is connected, the air 325 flows with a horizontal component in the x-direction towards the rear in the direction of the second housing end face 130 and the cut material is blown towards the rear, so that the blown-off cut material can be well received by the suction device or blown directly into the suction device.

[0058] Furthermore, by blowing the airflow 330 from the front onto the tooth row 100, it can be ensured that the airflow 330 is not interrupted or deflected by the guide device 155 and / or the saw blade 85 itself. This prevents the chips from, for example, obscuring a cutting line marked on the workpiece 15, so that the hand-held power tool 10 can be guided precisely along the cutting line. This improves the precision of the hand-held power tool 10.

[0059] As an alternative to the orientation of the first sub-section 210, it is also conceivable that the first sub-section 210 is aligned parallel to the receiving axis 75 and that the airflow 330 is injected into the cutting area 110 in a parallel direction. This is particularly advantageous if the first air duct 160 is arranged such that the first sub-section 210 is located particularly close to the tool holder 40, that is, closer to the tool holder 40 than to the first housing end face 125.

[0060] Fig. 5 shows a sectional view along the in Fig. 2 section plane AA shown through the in Fig. 2 hand-held power tools shown 10.

[0061] In Fig. In position 5, valve 170 is in the second valve position. In the second valve position, the valve body 235 is rotated about the axis of rotation 213 relative to the first valve position. This means, for example, that in Fig. 5 the second actuating lever 250 arranged on the left is located at the bottom and the first actuating lever 245 is located at the top, whereas in the first valve position (as in Fig. 4 shown) the second actuating lever 250 is located at the top and the first actuating lever 245 is located at the bottom.

[0062] In the second valve position, the ring section 240 covers the first valve channel 290, so that the first valve channel 290 and the connected first air channel 160 are fluidically separated from the conveying unit 175. However, the second valve channel 295 has a second overlap with the second valve opening 265. In the second valve position, the conveying unit 175 conveys the air 325 via the second valve opening 265 and the second valve channel 295 into the second air channel 165. The air 325 then exits at the end of the second air channel 165 at the second channel opening 211 (see Figure 1). Fig. 1) The air 325 flows in a further air stream 335 obliquely from back to front (in the feed direction V) towards the saw blade 85, so that the resulting chips are blown away from the workpiece 15 from back to front. The second valve position is particularly suitable when, for example, working overhead with the hand-held power tool 10.

[0063] Fig. Figure 6 shows a sectional view along the in Fig. 2 section plane AA shown through a hand-held machine tool 10 according to a second embodiment.

[0064] The hand-held power tool 10 is essentially identical to the one described in the Fig. The hand-held power tool 10 is described in sections 1 to 5. The following focuses exclusively on the differences between the two. Fig. 6 hand tool shown 10 compared to the one in the Fig. Hand tool shown in 1 to 5 is included.

[0065] In Fig. Figure 6 shows the valve 170 in the first valve position, with the valve body 235 opposite Fig. 4 is twisted in such a way that the actuating lever 245, 250 runs in a horizontal plane (parallel to the y-axis).

[0066] The operating principle of the hand-held power tool 10 corresponds to that described in Fig. 4. Functionality explained.

[0067] The second valve position of the hand-held power tool 10 corresponds to that in Fig. 5 explained the second valve position.

[0068] Fig. Figure 7 shows a sectional view along the in Fig. 2 section plane AA shown through the in Fig. 6 hand-held power tool shown 10.

[0069] Valve 170 has an additional third valve position. The blowing device 30 can have a vent channel 301. The valve housing has a third valve channel 320. The third valve channel 320 extends radially from the inner circumferential side 276 to the outside. The vent channel 301 is connected to the third valve channel 320. The vent channel 301 is connected to valve 170 on one side and opens into the surrounding area 305 of the hand-held power tool 10 on the other side. In the third valve position, valve 170 fluidically connects the conveying unit 175 to the vent channel 300. This design has the advantage that reliable cooling of the drive motor 60 can be ensured while simultaneously preventing blowing into the cutting area 110.

[0070] The above-described design of the hand-held machine tool 10 has the advantage that, by means of the valve body 235, the actuating lever 245, 250 can be rotated around the axis of rotation 213, allowing for particularly quick switching between the individual valve positions.

[0071] Fig. Figure 8 shows a side view of a hand-held machine tool 10 according to a third embodiment.

[0072] The hand-held power tool 10 is essentially a combination of the components described in the Fig. 1 to 5 shown hand tool 10 and the one in the Fig. 6 and Fig. 7 explained hand-held power tool 10. In the following, only the differences of the in Fig. 8 hand tool shown 10 compared to the one in the Fig. 6 and Fig. 7 hand tool shown 10 received.

[0073] The housing 20 defines a third air duct 310 instead of or in addition to the vent duct 301. The third air duct 310 is connected to the valve 170 on the inlet side and opens at the bottom of the housing 135. The third air duct 310 is located on one of the sides facing the second housing end face 130 and runs essentially vertically.

[0074] Fig. Figure 9 shows a perspective view of the valve body 235 of the in Fig. 8 hand tool shown 10.

[0075] The valve body 235 is essentially identical to the one in Fig. The valve body 235 shown in section 3 is formed. The following refers exclusively to the differences of the valve body shown in the following. Fig. Valve body 235 shown in 9 compared to the one in Fig. 3 valve bodies shown 235 received.

[0076] The valve body 235 has a third valve opening 315. The first and second valve openings 260, 265 are, for example, narrower in the axial direction than in Fig. The valves are shown in Figure 3 and are arranged in a common plane of rotation with respect to the axis of rotation 213. Axially offset from the first and second valve openings 260, 265, the third valve opening 315 is arranged circumferentially between the first valve opening 260 and the second valve opening 265. The third valve opening 315 has, by way of example, an identical configuration to the first and second valve openings 260, 265.

[0077] Fig. Figure 10 shows a cross-sectional view through the in Fig. 8 hand-held power tool shown 10 along a in Fig. Section BB shown in section 8. Fig. In version 10, valve 170 only has the first and third valve positions. The first valve position is in Fig. 4 explained. Fig. 10 the valve is in the second valve position.

[0078] The valve housing 270 has the third valve channel 320. The third valve channel 320 is in Fig. 10 is connected downstream to the third air channel 310. In the second valve position, the third valve opening 315 has a third overlap with the third valve channel 320. In the second valve position, air 325 is thus blown downwards onto the workpiece 15 via both the second air channel 165 and the third air channel 310. In particular, the air 325 from the third air channel 310 supports the removal of the chips by means of the extraction device.

Claims

[1] Hand-held power tool (10), in particular jigsaw, for producing a cut (115) in a feed direction (V) in a workpiece (15), - comprising a tool holder (40), a cutting area (110), a housing (20), a support device (35) for supporting the hand-held power tool (10) on the workpiece to be machined (15), in particular a base plate (50), and a blowing device (30), - wherein the housing (20) has a housing bottom (135) and a housing front (125), - wherein the tool holder (40) is designed to accommodate an insert tool (80), in particular a saw blade (85), along a mounting axis (75), - wherein the support device (35) can be placed against the workpiece (15) in a guide plane (55), - wherein the receiving axis (75) intersects the guide plane (55) in a cutting area (110), - wherein the blowing device (30) has a first air channel (160) which terminates in a first channel opening (205) which is arranged on the underside of the housing (135) in the feed direction (V) in front of the tool holder (40) and is designed to inject an air stream (330) into the cutting area (110), characterized by , that - the blowing device (30) further comprises a conveying unit (175) for generating the airflow and a second air channel (165), - wherein the blowing device (30) has a valve (170) which is switchable between a first valve position and a second valve position, - wherein the valve (170) is fluidically connected on the inlet side to the conveying unit (175) and on the outlet side to the first air duct (160) and the second air duct (165), - and wherein in the first valve position a fluidic connection is established between the conveying unit (175) and the first air duct (160) and in the second valve position a fluidic connection is established between the conveying unit (175) and the second air duct (165). [2] Hand-held power tool (10) according to claim 1, - wherein in the first valve position the first air channel (160) is fluidically connected to the conveying unit (175) and the second air channel (165) is fluidically separated from the conveying unit (175), - wherein in the second valve position the second air channel (165) is fluidically connected to the conveying unit (175) and the first air channel (160) is fluidically separated from the conveying unit (175). [3] Hand-held power tool (10) according to one of claims 1 or 2, - wherein the valve (170) has a third valve position, - wherein in the third valve position the first air channel (160) and the second air channel (165) are fluidically separated from the conveying unit (175). [4] Hand-held power tool (10) according to claim 3, - wherein the blowing device (30) has a venting channel (301), - wherein the vent channel (301) is connected to the valve (170) on one side and opens on another side into an environment (305) of the hand-held power tool (10), - wherein in the third valve position the vent channel (301) is fluidically connected to the pumping unit (175). [5] Hand-held power tool (10) according to any of the preceding claims, - wherein the conveying unit (175) has a fan wheel (300) arranged in a rotationally fixed manner on a drive shaft (65) of the drive motor (60), - wherein the valve (170) has a valve housing (270) and a valve body (235) rotatably mounted about the axis of rotation (213) with an annular section (240), - wherein the ring section (240) radially surrounds the fan wheel (300) on the outside, - wherein the ring section (240) has a first valve opening (260) and a second valve opening (265) arranged circumferentially offset to the first valve opening (260), - wherein in the first valve position the first valve opening (260) has a first overlap with a first valve channel (290) of the valve housing (270) and the ring section (240) closes a second valve channel (295), - wherein the first valve channel (290) is fluidically connected to the first air channel (160) and the second valve channel (295) is fluidically connected to the second air channel (165), - wherein in the second valve position the ring section (240) is arranged rotated circumferentially about the axis of rotation (213) relative to the first valve position, - wherein in the second valve position the first valve opening (260) is spaced apart from the first valve channel (290) and the ring section (240) closes the first valve channel (290), - wherein in the second valve position the second valve opening (265) has a second overlap with the second valve channel (295). [6] Hand-held power tool (10) according to claim 5, - wherein the valve housing (270) circumferentially surrounds the ring section (240) with an inner circumferential side (27) and rotatably supports the ring section (240) about the axis of rotation (213), - wherein the valve body (235) has at least one actuating lever (245, 250) extending radially outwards, - wherein the actuating lever (245, 250) is connected to the ring section (240), - wherein the housing (20) has at least one recess (280, 285), - wherein the recess (280, 285) opens onto an outer circumferential side (255) of the hand tool device (10), - wherein the actuating lever (245, 250) passes through the associated recess (280, 285). [7] Hand-held power tool (10) according to claim 5 or 6, - having a gearbox (70), - wherein the gearbox (70) is connected on the input side to the drive motor (60) and on the output side to the tool holder (40), - wherein the transmission (70) is configured to convert a rotary motion of the drive motor (60) into an oscillating motion of the tool holder (40), - wherein the first air duct (160) is guided at least partially around the gearbox (70) on a side of the gearbox (70) facing away from the cutting area (110). [8] Hand-held power tool (10) according to any of the preceding claims, - comprising a saw blade (85) with a saw section (90) and a shaft (95) connected to the saw section (90), - wherein the shaft (95) engages in the tool holder (40) and is connected to the tool holder (40), - wherein the saw section (90) is plate-shaped, and at least one row (100) of saw teeth (105) is arranged exclusively on a single side surface, - wherein the first air channel (160) is designed to direct the airflow (330) on a side facing the tooth row (100) substantially parallel to the saw section (90) or inclined obliquely towards the tooth row (100). [9] Hand-held power tool (10) according to one of the preceding claims, wherein the partial area (210) is arranged at an angle of 0° to 20° to the receiving axis (75).

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