The present application claims the benefit under 35 U.S.C. §119 of German Patent Application No. DE 102011089919.7 filed on Dec. 27, 2011, which is expressly incorporated herein by reference in its entirety.
The present invention relates to a hand-held tool device having at least one operating device via which the at least one first transmission ratio and a second transmission ratio and a percussion drilling mode are able to be set.
An example hand-held tool device in accordance with the present invention includes a protective device, which prevents the operation in the first transmission ratio in the percussion drilling mode. By an “operating device” one should understand, in this connection, particularly a device via which an operator is able to set an operating mode, at least of a striking mechanism of the hand-held tool device, and a transmission ratio particularly of a planetary transmission of the hand-held tool device. The operating device is preferably provided to show to the operator the currently set operating state, namely, advantageously by a device of at least one operating element of the operating device. “Provided” is to be understood in particular as specially designed and/or equipped. By “protective device” one should understand a device which protects the operator during a working procedure.
The protective device is preferably provided to protect the operator, especially in a blocking case of the percussion drilling mode, by the limitation of the maximum tool torque. By a “tool torque” one should particularly understand a torque brought about by the tool chuck particularly on an insertable tool. By a “maximum tool torque” one should understand particularly a tool torque that occurs in an operating mode in response to a soft blocking case. The maximum tool torque should be determined according to the standard DIN EN 60745. In a soft blocking case, the tool chuck is braked by the insertable tool slowly and uniformly, particularly within two revolutions of the tool chuck. By “transmission ratio” one should understand particularly an operating mode which is associated with a ratio of a rotational speed of a rotor of a drive unit of the hand-held tool device and a tool chuck of the hand-held tool device. The first transmission ratio preferably has a small maximum rotational speed and a large maximum tool torque, that is, particularly a tool torque greater than 15 Nm. The second transmission ratio preferably includes a large maximum rotational speed and a small maximum tool torque, that is, particularly a tool torque less than 15 Nm. By “percussion drilling mode” one should particularly understand an operating mode of the hand-held tool device in which the tool chuck and particularly a striking mechanism of the hand-held tool device drive the insertable tool in a rotating and striking manner. By the term “able to be set” one should particularly understand that the operator, using the operating device, is able to put the hand-held tool device at least into the first transmission ratio, into the second transmission ratio and/or into the percussion drilling mode. In addition, preferably one is able to set at least a screw mode and a drilling mode via the operating device. Furthermore, an additional transmission ratio and a chisel mode could be able to be set via the operating device. By a “screw mode” one should particularly understand an operating mode of the hand-held tool device, in which the tool chuck rotationally drives the insertable tool up to a maximum tool torque that is able to be set, namely, without a striking motion, in particular. By a “drilling mode” one should particularly understand an operating mode of the hand-held tool device, in which the tool chuck rotationally drives the insertable tool up to a maximum tool torque that is able to be set, namely, without a striking motion, in particular. By a “chisel mode” one should particularly understand an operating mode of the hand-held tool device in which the insertable tool is driven only in a striking manner. By “operation in the first transmission ratio” one should particularly understand an operating state in which the first transmission ratio is set. By the term “prevent” one should particularly understand, in this connection, that the protective device excludes the simultaneous operation in the first transmission ratio and in the percussion drilling mode. Because of the embodiment of the hand-held tool device according to the present invention, an especially safe percussion drilling operation is made possible in a constructively simple manner.
Moreover, it is provided that the protective device prevents switching over into the percussion drilling mode when the first transmission ratio is set, whereby a particularly simple, cost-effective and reliable construction is made possible. The protective device advantageously prevents the engaging of the operating element in a position assigned to the percussion drilling mode, when the first transmission ratio is set. The protective device particularly advantageously prevents the displacing of the operating element into a position assigned to the percussion drilling mode, when the first transmission ratio is set. Alternatively, the protective device could prevent an operation when the percussion drilling mode and the first transmission ratio are set at the same time, for example, by opening a mechanical clutch or particularly by the electrical switching off of the drive unit.
Moreover, it is provided that the protective device prevents switching over into the first transmission ratio when the percussion drilling mode is set, whereby a particularly simple, cost-effective and reliable construction is attainable. The protective device advantageously prevents the engaging of the operating element in a position assigned to the second transmission ratio, when the percussion drilling mode is set. The protective device particularly advantageously prevents the displacing of the operating element into a position assigned to the first transmission ratio, when the percussion drilling mode is set.
Furthermore, it is provided that a maximum tool torque in the first transmission ratio amount to more than 15 Nm, whereby, in the drilling mode and the screw mode, a particularly effective operation is made possible.
In addition, it is provided that a maximum tool torque in the second transmission ratio amount to less than 15 Nm, whereby, in the drilling mode, an advantageously high rotational speed and in the percussion drilling mode a particularly safe operation is attainable.
Furthermore, the operating device may have a first operating element, via which the first transmission ratio and the second transmission ratio are able to be set, whereby a particularly operator-friendly selection of the transmission ratios is made possible in a constructively simple manner. By an “operating element” one should particularly understand a component which outputs a characteristic variable that is a function of an operator input, particularly an electric one and/or advantageously a mechanical one. The operating element is preferably developed as an operating element that appears meaningful to one skilled in the art, particularly advantageously as a mechanically acting switch.
In one advantageous development of the present invention, it is provided that the operating device have a second operating element, via which at least the percussion drilling mode is able to be set, whereby, in a constructively simple manner, the transfer of the setting is able to be made from the operating elements to a planetary transmission and a striking mechanism of the hand-held tool device.
Moreover, it is provided that the protective device be developed at least partially as one piece with the operating device, whereby a particularly safe operation is made possible using an advantageously simple construction. By “at least partially as one piece” one should particularly understand in one continuous material, such as by a welding process and/or an adhesion process, etc., and particularly advantageously connected in an attached form, such as by production by casting and/or production in a monocomponent or multicomponent injection molding method.
In addition, the hand-held tool device may include a torque limitation unit that is able to be set, which is provided for limiting a maximum tool torque in a screw mode, whereby a particularly convenient operation in the screw mode is attainable. The torque limitation unit and the protective device are preferably developed separately from each other. By “torque limitation unit” one should particularly understand a unit provided to limit a maximum tool torque acting on a workpiece, especially on a screw. By “able to be set” one should particularly understand, in this connection, that a maximum tool torque is able to be selected by an operator in at least three stages, advantageously at least five stages.
Furthermore, the operating device may be provided to deactivate the torque limitation unit in a drilling mode, whereby advantageously high tool torques are able to be supplied for a drilling operation, particularly for drill bits having a large diameter. By “deactivate” one should understand, in this connection, that the operating device prevents the action of the torque limitation unit in the drilling mode, whereby a maximum tool torque is a function of the torque of the drive unit and the selected transmission ratio.
In addition, the present invention relates to an hand-held tool having an hand-held tool device according to the present invention. The hand-held tool is preferably provided to actuate the insertable tool in a screw mode, in a drilling mode, in a screw drilling mode and particularly in a chisel mode.
Further advantages are derived from the description below of the figures. The figures show five exemplary embodiments of the present invention. The figures and the description contain numerous features in combination. One skilled in the art will expediently also consider the features individually, and will combine them into useful further combinations.
Tool guide unit 20a includes a tool chuck 36a and a tool spindle 38a. During a working process, tool chuck 36a fastens an insertable tool not shown here, such as a drill or a screw bit. Tool chuck 36a fastens the insertable tool in a force-locking manner. Tool chuck 36a has three clamping jaws that an operator is able to fasten movably, which fasten the insertable tool during a working process. In addition, tool chuck 36a fastens the insertable tool during a working process in a manner that is axially immovable with respect to tool chuck 36a and particularly with respect to tool spindle 38a. One part of tool chuck 36a and tool spindle 38a are connected to each other relatively immovably. In this case, tool chuck 36a and tool spindle 38a are screwed together. Hand-held tool device 12a has a bearing device 40a, which supports tool spindle 38a on a side facing tool chuck 36a. Bearing device 40a supports tool spindle 38a in an axially displaceable manner. Bearing device 40a is connected axially fixed to tool spindle 38a. Bearing device 40a is supported axially movable to hand-held tool housing 14a. Hand-held tool device 12a has an additional bearing device 41a, which supports tool spindle 38a on a side facing planetary transmission 28a. In this embodiment, bearing device 41a is a roller bearing, in this case as a needle bearing, whereby a support having little play is made possible. Bearing device 41a supports tool spindle 38a in an axially displaceable manner. A striking mechanism spindle 46a encloses bearing device 41a. Bearing device 41a is functionally situated between tool spindle 38a and striking mechanism spindle 46a.
Tool spindle 38a includes a striking surface 42a, which a beater 44a of the striking mechanism 22a beats during a percussion drilling operation. Beater 44a has a mass that is maximally two-thirds the size of the mass of tool guide unit 20a. In this case, the mass of beater 44a is less than one-half as great as the mass of tool guide unit 20a. The mass of beater 44a amounts to about 45% of the mass of tool guide unit 20a.
In
Striking mechanism spring 48a accelerates beater 44a before a strike in striking direction 54a. For this purpose, hand-held tool housing 14a supports striking mechanism spring 48a on a side facing away from beater 44a. Striking mechanism spring 48a presses directly against beater 44a. Beater 44a has a spring fastening 60a. Spring fastening 60a is developed as an annular depression.
In this embodiment, striking mechanism spindle 46a is a hollow shaft. Planetary transmission 28a drives striking mechanism spindle 46a. For this purpose, striking mechanism spindle 46a has a toothing 76a on the side facing away from tool chuck 36a. Guiding curves 66a, 68a each have an impact-free regions 78a, 80a, an impact winding region 82a, 84a and an assembly recess 86a, 88a. During assembly, connectors 70a, 72a are inserted through assembly recesses 86a, 88a into fastening recesses 74a of beater 44a. In a percussion drilling operation, striking mechanism spindle 46a rotates clockwise as seen in striking direction 54a. Impact winding regions 82a, 84a are developed to be spiral-shaped. They extend over 180 degrees about a rotational axis 90a of striking mechanism spindle 46a. Impact winding regions 82a, 84a move connectors 70a, 72a, and with that, beater 44a counter to striking direction 54a in the percussion drilling operation. Consequently, striking mechanism 22a has connectors 70a, 72a which, in at least one operating state, transfer a motion from striking mechanism spindle 46a to beater 44a.
Impact-free regions 78a, 80a each connect two ends 92a, 94a, 96a, 98a of impact winding regions 82a, 84a. Impact-free regions 78a, 80a extend over 180 degrees about a rotational axis 90a of striking mechanism spindle 46a. Impact-free regions 78a, 80a each have an impact side 100a, 102a which, starting from an end 94a, 96a of impact winding region 82a, facing planetary transmission 28a, runs approximately parallel to striking direction 54a. After the connectors 70a, 72a penetrate impact-free regions 78a, 80a, striking mechanism spring 48a accelerates beater 44a and connecting means 70a, 72a in striking direction 54a. In this context, connecting means 70a, 72a move through impact free-wheeling regions 78a, 80a, without experiencing an axial force, until beater 44a hits striking surface 42a. Curve guides 62a, 64a are situated about rotational axis 90a, offset by 180 degrees. Curve guides 62a, 64a are situated one behind the other in the axial direction.
Planetary transmission 28a has first planetary transmission stage 104a, a second planetary transmission stage 106a, a third planetary transmission stage 108a and a fourth planetary transmission stage 110a
During a percussion drilling operation, first striking mechanism shut-off device 24a fixes internal geared wheel 116a of first planetary transmission stage 104a immovable with respect to hand-held tool housing 14a. First striking mechanism shut-off device 24a is provided to switch on beater driving device 50a in response to a first right-hand drilling rotation direction, and to switch off automatically beater driving device 50a in response to a second, left-hand drilling rotation direction. First striking mechanism shut-off device 24a acts on internal geared wheel 116a of first planetary transmission stage 104a. First striking mechanism shut-off device 24a blocks internal geared wheel 116a of first planetary transmission stage 104a at the first right-hand drilling rotation direction. First striking mechanism shut-off device 24a releases internal geared wheel 116a of first planetary transmission stage 104a in response to second, left-hand drilling rotation direction, so that it is able to rotate. For this purpose, striking mechanism shut-off device 24a has three clamping mechanisms 122a. Clamping mechanisms 122a each include a blocking arrangement 124a, a first clamping surface 126a, a second clamping surface 128a and free-wheeling surfaces 130a. Seal 124a is developed as a roller. First clamping surface 126a forms an area, lying outside, of a surface of internal geared wheel 116a of first planetary transmission stage 104a. Second clamping surface 128a is situated immovable with respect to hand-held tool housing 14a. During an operation in the first, right-hand drilling rotation direction, blocking arrangement 124a clamp between first clamping surfaces 126a and second clamping surface 128a. During an operation in the second, left-hand drilling rotation direction, free-wheeling areas 130a guide blocking arrangement 124a and prevent clamping.
Furthermore,
Moreover,
Second striking mechanism shut-off device 26a has a striking mechanism shut-off clutch 142a. Striking mechanism shut-off clutch 142a is partially developed as one piece with planetary transmission 28a. Striking mechanism shut-off clutch 142a is situated between first planetary transmission stage 104a and second planetary transmission stage 106a. Striking mechanism shut-off clutch 142a has a first clutch 144a which is connected torsionally fixed to a planet carrier 114a of first planetary transmission stage 104a. Striking mechanism shut-off clutch 142a has a second clutch element 146a which is connected torsionally fixed to a planet carrier 120a of first planetary transmission stage 106a. In the screw mode and the drilling mode shown, striking mechanism shut-off clutch 142a is opened. In a percussion drilling operation, tool spindle 38a transfers an axial clutching force to striking mechanism shut-off clutch 142a when the operator presses an insertable tool against a workpiece. The clutching force closes striking mechanism shut-off clutch 142a. In
Planet carrier 120a of second planetary transmission stage 106a is developed as two parts. A first part 150a of planet carrier 120a of second planetary transmission stage 106a is connected torsionally fixed to tool spindle 38a. First part 150a of planet carrier 120a is connected to tool spindle 38a in an axially displaceable manner, whereby planet carrier 120a remains torsionally coupled to tool spindle 38a even during a striking maneuver. Thus, first part 150a is permanently connected to tool spindle 38a. First part 150a of planet carrier 120a is supported dispaceably against striking mechanism switching spring 148a. A second part 152a of planet carrier 120a of second planetary transmission stage 106a is connected torsionally fixed to first part 150a of planet carrier 120a. First part 150a and second part 152a of planet carrier 120a are connected to each other in an axially displaceable manner. First part 150a and second part 152a of planet carrier 120a are connected permanently in a torsionally fixed manner.
Control element 134a of hand-held tool device 12a has supporting device 190a, which, at least during a drilling operation, prevents an axial motion of impact device 182a. For this purpose, supporting device 190a support impact device 182a in the axial direction. Impact device 182a has screw recesses 192a, into which impact device 182a dip in response to reaching the maximum tool torque, particularly in a screw operation as shown in
Internal geared wheel 204a of third planetary transmission stage 108a is supported displaceably in the axial direction, as shown in
Operating device 32a has a first operating element 218a and a second operating element 220a. First operating element 218a is situated on the side of hand-held tool housing 14a that faces away from handle 18a. It is supported movably parallel to the axial direction of planetary transmission 28a. First operating element 218a is connected via adjusting device 222a of operating device 32a to internal geared wheel 204a of third planetary transmission stage 108a in the axial direction. Internal geared wheel 204a of third planetary transmission stage 108a has a groove 224a in which adjusting device 222a engages. Thus, internal geared wheel 204a of third planetary transmission stage 108a is connected to adjusting means 222a in the axial direction, axially rotatable with respect to adjusting means 222a. Adjusting device 222a is developed to be springy, whereby the transmission from a rotary position of internal geared wheel 204a of third planetary transmission stage 108a is able to be adjusted independently. When first operating element 218a is pushed in the direction of tool chuck 36a, this sets the first transmission. When second operating element 220a is pushed away from tool chuck 36a, this sets the second transmission.
Second operating element 220a is situated on the side of hand-held tool housing 14a that faces away from handle 18a. Second operating element 220a is situated displaceable about an axis which is aligned parallel to the axial direction of planetary transmission 28a. Second operating element 220a is connected torsionally fixed to control element 134a of hand-held tool device 12a. Using second operating element 220a, one is able to set the screw mode, the drilling mode and the percussion drilling mode. When second operating element 220a is pushed to the left, as seen in striking direction 54a, this sets the percussion drilling mode. When second operating element 220a is pushed to the right, as seen in striking direction 54a, this sets the screw mode. When second operating element 220a is pushed to the middle, as seen in striking direction 54a, this sets the drilling mode.
In the example embodiment, drive unit 30a is developed as an electric motor. Drive unit 30a has a maximum torque which causes a maximum tool torque in the first transmission of more than 15 Nm, and in the second transmission of less than 15 Nm. The maximum tool torque in the first transmission amounts to 30 Nm. The maximum tool torque in the second transmission amounts to 10 Nm. In this context, the tool torque should be determined according to Standard DIN EN 60745.
Striking mechanism switching spring 148a of hand-held tool device 12a, in the case of a percussion drilling operation, opens striking mechanism shut-off clutch 142a when the operator removes the insertable tool from the workpiece. Striking mechanism switching spring 148a is situated coaxially to planetary transmission stages 104a, 106a, 108a, 110a of planetary transmission 28a. Second planetary transmission stage 106a and third planetary transmission stage 108a enclose striking mechanism switching spring 148a in each case in at least one plane, which is aligned perpendicular to the axial direction of planetary transmission 28a. Second planetary transmission stage 106a and third planetary transmission stage 108a are each situated functionally between at least two additional planetary transmission stages 104a, 106a, 108a, 110a of planetary transmission 28a. Planet carrier 120a of second planetary transmission stage 106a supports striking mechanism switching spring 148a on the side facing away from tool chuck 36a.
Protective device 226e has a freewheeling region 248e bordered by first operating element 218e. Protective device 226e has a freewheeling region 250e bordered by second operating element 250e. Freewheeling region 248e of first operating element 218e enables the setting of the screw mode, the drilling mode and the percussion drilling operation when a second transmission has been set. Freewheeling region 250e of second operating element 220e enables the setting of the screw mode and the drilling mode when a second transmission has been set.
In the percussion drilling operation, protective device 226e prevents setting the first transmission. When the first transmission has been set, protective device 226e prevents setting the percussion drilling operation.
Number | Date | Country | Kind |
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10 2011 089 919.7 | Dec 2011 | DE | national |