This application claims priority under 35 U.S.C. § 119 to patent application no. DE 10 2018 216 726.5, filed on Sep. 28, 2018 in Germany, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

Described in EP 2 639 010 A1 is an ancillary handle for a hand-held power tool, which is connected to the hand-held power tool via a first clamp and to a dust extraction system via a second clamp.

SUMMARY

The disclosure relates to a fastening device for a dust extraction device, which is designed to detachably connect the dust extraction device to a hand-held power tool, in particular a hammer drill, having a first connection unit for connecting the dust extraction device to the hand-held power tool by form closure. It is proposed that the fastening device have a second connection unit for connecting the dust extraction device to the hand-held power tool by force closure. It is thereby possible, advantageously, to realize secure and substantially zero-play mounting of the dust extraction device on the hand-held power tool.

The dust extraction device is preferably realized as an accessory for the hand-held power tool, the hand-held power tool also being able to be used without the accessory. The dust extraction device is designed, in particular, to extract dust material by suction, for example drilling dust/grinding dust/sawdust, as work is being performed on a workpiece by the hand-held power tool. In particular, the dust extraction device has an air channel, through which an airflow is routed during operation. The airflow may be generated, in particular, by means of a fan unit. The fan unit may be arranged in the dust extraction device, in the hand-held power tool or in an external dust extractor. The fan unit comprises at least one ventilator element, which is realized, for example, as a radial ventilator or as an axial ventilator. The hand-held power tool may be realized, for example, as a hammer drill, power drill, chipping hammer, percussive power drill, angle grinder, power sander, saber saw, etc, these power tools having in common that drilling dust/grinding dust/sawdust is produced during operation. The hand-held power tool may be realized as a mains-power operated appliance or as a battery-operated appliance.

The first connection unit and the second connection unit are assigned to a mechanical interface of the dust extraction device, which is designed, in particular, for detachably connecting the dust extraction device to the hand-held power tool, in particular connecting a housing of the dust extraction device to a housing of the hand-held power tool, by force closure and form closure. In the context of this application, a “detachable connection” is to be understood to mean, in particular, a connection that can be detached without use of any tools. In the context of this application, a form closure is to be understood to mean an inhibited movement of a component along a form-closure axis, the movement being impeded by a further component, for example by stopping. In particular, the components bear against each other along the form-closure axis, or bear against each other with play. The form closure in this case acts, in particular, in both mutually opposite directions on the form-closure axis. Preferably, the form closure acts along two mutually perpendicular form-closure axes. In the context of this application, a force closure is to be understood to mean, in particular, an impeded movement of a component along a force-closure axis. In this case, the movement of the component is not impeded by a further component. The impeding is effected, in particular, by means of a frictional contact. The first connection unit may additionally be designed to connect the dust extraction device to the hand-held power tool by force closure. The second connection unit may additionally be designed to connect the dust extraction device to the hand-held power tool by form closure.

In addition, it is likewise conceivable for the dust extraction device to have an electrical interface, via which, for example, the dust extraction device can be supplied with energy, exchange information or be controlled. The electrical interface may be realized, for example, as a universal interface, in particular as a USB interface. The electrical interface may have electrical contact elements, which make an electrical connection via a physical contact with corresponding electrical contact elements that are arranged, for example, on a battery pack, on a load or on a charging device. In particular, the electrical interface is realized, at least partly, as a battery interface for detachably connecting the dust extraction device to a battery pack, in particular to a battery pack of a hand-held power tool. The battery pack has a housing, in which at least one battery cell, for example a Li-ion round cell, is accommodated. The battery pack is preferably detachably connected to the dust extraction device. The battery pack is preferably realized as a slide-on battery pack that, for the purpose of connection, is slid linearly onto the dust extraction device via guide rails. The battery pack is realized, in particular, as an 18 V battery pack having, for example, 5 or 10 battery cells.

Preferably, the dust extraction device has a dust collection chamber. The dust collection chamber is designed, in particular, to receive the dust material produced during operation of the hand-held power tool. The dust collection chamber is arranged, in particular, in such a manner that the airflow is at least partly routed through the dust collection chamber. In particular, the dust collection chamber has a dust collection chamber housing. The dust collection chamber housing may be integrated into the housing of the dust extraction device, or alternatively may be realized such that it can be detachably connected to it. The dust collection chamber has an inlet, via which the airflow enters the dust collection chamber, and an outlet, via which the airflow exits the dust collection chamber. The inlet and the outlet of the dust collection chamber are preferably realized separately from each other. Furthermore, it is conceivable for the dust collection chamber to have an emptying opening, which is designed for emptying the dust collection chamber. Preferably, the emptying opening can be closed, for example by means of an emptying flap. The dust extraction device, in particular the dust collection chamber of the dust extraction device, has in particular a filter unit for filtering the dust material out of the airflow. The filter unit is arranged, in particular, in the region of the outlet of the dust collection chamber. The filter unit can be connected, in particular detachably, to the dust extraction device, preferably can be detachably connected to the dust collection chamber of the dust extraction device. The filter unit has at least one filter element. The filter element may be composed, for example, of a felt, a non-woven fabric, a woven fabric, a paper or the like. The filter element is realized, in particular, as a microfilter or fine-dust filter, preferably as a HEPA filter.

Furthermore, it is proposed that the first connection unit be arranged at a distance apart from the second connection unit along a direction of connection. Advantageously, the mechanical stability of the dust extraction device on the hand-held power tool can thereby be further improved. In this context, a direction of connection is to be understood to mean, in particular, the direction of connection of the dust extraction device in the process of connection to the hand-held power tool. The direction of connection may extend linearly, or about a pivot axis. The direction of connection may be substantially parallel to, cross or be substantially perpendicular to the work axis of the hand-held power tool. “At a distance apart” in this context is to be understood to mean, in particular, that arranged between the first connection unit and the second connection unit there is a region in which the first and the second connection unit do not overlap perpendicularly in relation to the direction of connection. The length of this region along the direction of connection is the distance between the first connection unit and the second connection unit along the direction of connection. The length of the region corresponds, in particular, to at least 20% of the length of the dust extraction device along the direction of connection, preferably at least 35% of the length of the dust extraction device, more preferably at least 50% of the length of the dust extraction device. Alternatively, it is also conceivable the first connection unit is assigned at a distance apart from the second connection unit along or parallel to a telescoping axis of a telescoping unit of the dust extraction device. Preferably, the telescoping axis is substantially parallel to the connection axis.

Furthermore, it is proposed that the first connection unit have at least one guide element, in particular at least two guide elements, the guide element being realized, in particular, as a guide rail. Advantageously, stable guiding of the dust extraction device during the connection process can thereby be achieved. The at least two guide elements are preferably parallel to each other. In particular, the guide elements constitute a single piece with the housing of the dust extraction device.

It is additionally proposed that the guide element have at least two differing form closure regions. It is thereby possible, advantageously, to ensure a greatest possible degree of compatibility with a variety of hand-held power tools that, in turn, have corresponding form closure elements. In particular, the differing form closure regions differ in their cross section and/or differ in their contour. The cross section may be, for example, angular, rectangular, rounded, swallowtail-shaped, etc.

Furthermore, it is proposed that the second connection unit have a locking unit that can be actuated manually. Advantageously, unwanted detachment of the dust extraction device from the hand-held power tool can thereby be prevented. Preferably, the locking unit is of a self-latching design. In particular, the locking unit is realized in such a manner that it latches-in automatically at the end of the connection process. Preferably, the locking unit has a locking element to which a force is applied, via a restoring element, in the direction of a locking position. The restoring element is realized, in particular, as a spring element. The spring element may be realized, for example, as an annular spring, as a helical spring, as a spiral spring, as a wrap spring, etc.

Furthermore, it is proposed that the second connection unit have an ancillary handle, the ancillary handle having a fixing element for fixing the ancillary handle to the hand-held power tool. The ancillary handle is realized, in particular, so as to be detachable from the hand-held power tool, in particular from the housing of the hand-held power tool.

It is additionally proposed that the restoring element act upon the fixing element of the ancillary handle via the locking element of the locking unit. Advantageously, effective fixing can thereby be realized. In particular, the restoring bears directly against the locking element, and the locking element bears directly against the fixing element.

Furthermore, it is proposed that, in the locked state, the ancillary handle be realized so as to be movable relative to the hand-held power tool. Advantageously, the position of the ancillary handle can thereby be optimally set by the user. In particular, in this case the ancillary handle is realized so as to be rotatable by at least 30°, preferably by at least 60°, more preferably by at least 150°, about a pivot axis. The pivot axis is preferably parallel to or substantially coaxial with the work axis of the hand-held power tool. Preferably, when the dust extraction device has been fastened, or fixed, to the hand-held power tool, no relative movement of the ancillary handle with respect to the housing of the hand-held power tool is possible.

Furthermore, it is proposed that the fastening device have a connection housing part, which is connected to at least one further housing part of the dust extraction device, in particular at least two further housing parts of the dust extraction device, via at least one first fastening element and via at least one second fastening element. In particular, the second connection unit and the second connection unit are arranged on the connection housing part. Preferably, the first connection unit and/or the second connection unit are realized so as to constitute, at least partly, in particular fully, a single piece with the connection housing part. The first fastening element and the second fastening element may be realized so as to be substantially identical.

It is additionally proposed that the at least one first fastening element be arranged in front of the first connection unit and the second connection unit in the direction of connection, and the at least one second fastening element be arranged after the first and the second connection unit in the direction of connection. Advantageously, particularly stable connection of the connection housing part can thereby be realized.

In particular, a distance between the first fastening element and the second fastening element corresponds to at least 65%, preferably at least 80%, of a length of the housing of the dust extraction device.

Furthermore, the disclosure relates to a dust extraction device for a hand-held power tool, having a fastening device as previously described.

Furthermore, the disclosure relates to a system composed of a first hand-held power tool, a second hand-held power tool and a dust extraction device, having a fastening device, which is designed to detachably connect the dust extraction device to the first and the second hand-held power tool, having a first connection unit for connecting the dust extraction device to the hand-held power tool by form closure, the first connection unit having at least one guide element that has at least two differing form-closure regions. It is proposed that one of the form-closure regions be designed for connection to the first hand-held power tool by form closure, and the other form-closure region is designed for connection to the second hand-held power tool by form closure. Advantageously, it is thereby possible to realize stable connection of the dust extraction device to hand-held power tools that have differing housings.

