Patent Application
20240383124
The invention relates to a handheld processing tool having a housing and having at least one handle connected to the housing, for guiding the processing tool, and having a suspension means for suspending the processing tool belonging to the class of patent according to claim 1.
Working with handheld processing tools, in particular with handheld power tools, on ladders or scaffolding often presents operators with the challenge of safely putting down or hanging their processing tool when not in use. This is useful not only for easier handling, but also for the safety of people who move or stay under the ladder or scaffold.
DE 20 2013 004 302 U1 discloses a handheld power tool having a housing and having at least one storage unit for storing insertion tools, at least one suspension means, and at least one marking unit. The housing comprises at least one fastening means designed to interchangeably fasten the storage unit, the suspension means, or the marking unit to the housing using at least one fastening element.
Known from WO 19206762 A1 is an arrangement is known with a side handle for a handheld power tool and a suspension means, the suspension means comprising an eyelet portion configured to be connected to a safety belt. The side handle also comprises a clamping ring configured to attach the side handle to a round portion of the handheld power tool, whereby the suspension means is attached to the clamping ring.
EP 3 658 336 A1 discloses a machine tool having a suspension means for holding the machine tool. The suspension means comprises a hook having an insertion portion, whereby the insertion portion of the hook is insertable into a receiving portion of the suspension means. The suspension means further comprises a fastening portion for releasably fastening the suspension means to a housing of the machine tool, and a securing means for securing the suspension means to the housing. The receiving portion comprises an opening in the axial direction for receiving and rotatably mounting the insertion portion of the hook. The suspension means further comprises a first locking device, which interacts with the receiving portion and is coupled to the insertion portion in a rotationally fixed manner, for defining a rotational position of the hook relative to the suspension means. The first locking device comprises at least one spring arrangement and the receiving portion comprises at least one recess, whereby the at least one spring arrangement is configured to engage with the at least one recess in the receiving portion.
However, the known suspension means are all very strongly influenced by the suspension stability of the accessories (e.g., removable battery packs, suction modules, insertion tools, etc.) mounted on the handheld processing tool. Furthermore, these solutions often result in a significant increase in the outer contour of the processing tool, which in particular leads to an increase in the so-called corner dimension, an indicator that describes how far a drill hole can be drilled into a corner, particularly in the case of handheld drills, drill hammers or screwdrivers.
Therefore, the object of the invention is to increase the suspension safety of a handheld processing tool without significantly increasing its outer contour or geometry.
According to the invention, it is provided that the suspension means is arranged, with an axial displacement region and a suspension region extending substantially transversely thereto, around at least part of a contour of the handle of the handheld processing tool such that the suspension means, in a first locking position, is inserted into the housing in a largely surface-neutral manner and, in at least one second locking position, is ejected out of the housing, whereby the suspension region, in the at least one second locking position, can be rotated by at least one opening angle of at least 90° with respect to the first locking position in a tangentially locking manner.
The surface-neutral storage option of the suspension in the first locking position means that any risk of injury to the operator from otherwise protruding parts can be avoided. In addition, there is a significantly reduced risk of damage to the processing tool or the suspension means in the event of an impact of the falling processing tool on the suspension means in particular. The suspension means is also better protected from external influences, such as impacts, accidental contact, etc., when the processing tool is in its first locking position during operation. As a result of the non-enlarged corner dimension, more convenient and flexible working with the handheld processing tool is possible. The arrangement of the suspension around a contour of the handle of the processing tool, in particular a main handle arranged at the rear end of the processing tool, makes it possible, in conjunction with the extension of the suspension means to the second locking position, to space a suspension point of the suspension means from a center of gravity of the processing tool such that the suspension safety is increased significantly and the suspension behavior is largely independent of the additional weight of any accessories used, such as one or more removable battery packs, an suction module, various insertion tools, etc.
The term “handheld processing tools” is understood to include battery-powered and/or grid-powered handheld power tools for processing parts by means of an electrically-powered insertion tool, such as a drill, a chisel, a grinding or polishing disc, a saw blade, a knife, or the like. Typical handheld power tools in this context include screwdrivers, impact drills, drill hammers, chisels, planers, angular grinders, oscillating sanders, polishing machines, or the like. However, a handheld processing tool is also to be understood as a measuring device, e.g. a rangefinder, a leveling device, a wall scanner, a spirit level, or the like. Handheld processing tools also include garden tools and construction equipment such as lawn trimmers, branch saws, tilling and trenching machines, blowers, or the like. In this case, the drive can be powered by an electric motor and an internal combustion engine. Furthermore, the invention is applicable to handheld household appliances, such as vacuum cleaners, mixers, etc.
The axial displacement region is understood to be the region of the suspension means that can be inserted in an axial direction, in particular in a main working direction of the handheld processing tool, into the housing of the processing tool for moving it into the first locking position and out of it for moving it into the second locking position. A suspension region extending substantially transverse to the axial displacement region is to be understood as the region of the suspension means that is used to suspend the processing tool, to which, e.g., a carrying strap or the like can be attached, or which can be suspended via a suitable protrusion or other holding element of a scaffold, a ladder, a wall, or the like. The term “substantially transverse” is intended to indicate that the suspension region can be arranged at an angle of approximately 60 to 120° to the displacement region. In addition, the suspension region itself can feature any shape, e.g. an arc, a triangle, a polygon, a meander, a zigzag path, or the like. Therefore, “substantially transverse” defines the path of the suspension region from its starting point at the adjacent displacement region to its end point, where a hook-shaped end adjoins the suspension region, which engages into a first undercut recess of the housing in the first locking position. A particular advantage of the hook-shaped end is that it provides a simple locking means for the first locking position on the one hand, which on the other hand also serves as an additional means of securing the suspension region in the second locking position.
In a further embodiment, the suspension means is lockable in a third locking position by the hook-shaped end engaging in a second undercut recess of the housing adjacent to the first undercut recess. As a result, it is possible to hang up or hold the processing tool by means of a loop, in particular a hand loop, a strap, or the like, without the need to substantially increase the outer contour of the handle. The suspension region, together with the displacement region and the hook-shaped end engaged in the third locking position, forms a closed strap which holds the loop securely in place.
In order to prevent severe damage to the processing tool or the slightly projecting suspension means in the event of an impact of the falling processing tool on the suspension means engaged in the third locking position, a bar between the first and the second undercut cut recess is designed to break in a specific manner. The bar arranged on the housing of the processing tool can be correspondingly thin or made of a softer material. A particular advantage is the replaceable bar. In this way, the processing tool can be further used even after a breakage of the bar without functional limitations.
The axial displacement region of the suspension means is guided in a resilient manner within a cylindrical guide bore in the housing. The guidance is in this case performed by a compression spring. This makes the suspension means very easy to operate with defined end states and/or locking positions.
By applying pressure to the suspension means, in particular to the suspension region, against the resilient force in conjunction with a slight tangential rotation of a few degrees, in particular by less than 10°, the hook-shaped end can be released by the operator from the undercut recess of the first or third locking position in order to move the suspension means to another locking position. In a further embodiment, the axial displacement region is formed from a cylindrical shaft, to the open end of which a sliding element is attached, which slides in a guide cylinder, whereby the compression spring is supported at one end of the guide cylinder and at the other end on the sliding element.
In one embodiment, it is also provided that the guide cylinder is formed by the guide bore of the housing and by a lateral retaining cover, which covers the guide bore over the axial displacement region of the suspension means within the housing. This makes it particularly easy to mount the suspension means in the housing of the processing tool. For this purpose, the axial displacement of the suspension means is guided through the guide bore of the housing or the handle in order to subsequently attach the sliding element to the open end of the axial displacement region. One end of the compression spring then pushes on the mounted sliding element. Finally, when mounting the side retaining cover, the free spring end is aligned on a spring cross at the end of the guide cylinder.
Furthermore, the sliding element and/or the cylindrical shaft features a locking geometry for tangentially locking the suspension means in the at least one second locking position. In this way, the suspension means can be utilized with different tangential extension positions of the suspension region, which enables optimum handling during suspension depending on the weight distribution and center of gravity of the processing tool.
In order to prevent accidental changes to the tangential opening position, in particular when the processing tool is suspended, the locking geometry is designed with a particular advantage such that self-locking is achieved by an axial force flow in the direction of the resilient force of the compression spring.
In the case of handheld processing tools provided with a removable battery pack, the suspension means is advantageously arranged between the handle and an electromechanical interface for the removable battery pack. The resulting high uniformity of the individual components makes it easier to transfer the suspension means according to the invention to processing tools with the same or similar arrangement or geometry of the handle and battery pack interface.
The voltage of a removable battery pack is typically a multiple of the voltage of a single energy store cell and results from the interconnection (parallel or in series) of the individual energy store cells. The energy storage cells are preferably designed as lithium-based energy storage cells, e.g., Li-ion, Li-po, Li-metal, or the like. However, removable battery packs with Ni—Cd, Ni—MH cells or other suitable cell types can also be used. For common Li-Ion energy storage cells with a cell voltage of 3.6 V, examples of voltage classes are 3.6 V, 7.2 V, 10.8 V, 14.4 V, 18 V, 36 V, etc. It should also be noted that the design of the electromechanical interfaces of a removable battery pack and the processing tool, as well as the associated receptacles for frictional and/or interlocking releasable connection, are not intended to be the subject matter of this invention. A skilled person will select a suitable embodiment for the battery pack interface depending on the power or voltage class of the processing tool and/or the removable battery pack. The embodiments shown in the drawings are therefore only to be understood by way of example.
The invention is explained hereinafter with reference to
Shown are:
The removable battery pack 14 is substantially a conventional removable battery pack 14 with a housing 20, which, on a first side wall or its top side, comprises the first electromechanical interface 16 for releasable connection to the electromechanical counter-interface 16 of the drill hammer 10. The removable battery pack 14 is discharged during operation of the drill hammer 10. As previously mentioned hereinabove, the battery voltage of the removable battery pack 14 generally results from a multiple of the individual voltages of the energy store cells (not shown) as a function of their connection (in parallel or in series). Preferably, the energy store cells are designed as lithium-based battery cells, e.g., Li-ion, Li-po, Li-metal, or the like. However, a removable battery pack with Ni—Cd, Ni—MH cells or other suitable cell types is conceivable. The invention can also be applied without limitation to a drill hammer 10 operated at grid voltage, e.g. 230 VAC.
The drill hammer 10 comprises a striking mechanism (not shown in greater detail) for driving an insertion tool 24, e.g. a drill bit or a chisel. which can be alternately held in a drill chuck 22. The striking mechanism is driven by an electric motor arranged in a housing 24 with a downstream transmission, which is supplied with energy by power electronics. The power electronics are controlled via a control unit or regulating unit integrated in the drill hammer 10 for regulating or controlling the electric motor, e.g. as a function of a main switch 26 that can be actuated by an operator. The main switch 26 is arranged in a main handle 28 of the drill hammer 10. In a known manner, the main handle 28 is coupled to the housing 18 in a vibration-damped manner by a damping device 30 to protect the operator from excessive vibration during prolonged work operations. The same applies to an additional handle 32 arranged in the vicinity of the drill chuck 22. The operator can rotate this in a tangential direction TW, relative to a main working direction W of the drill hammer 10 via a tensioning and clamping device 34 and thus adjust it according to their needs. It is also possible to completely remove the additional handle 32.
By means of an operating mode switch 36 located in the housing 18, the operator can switch between different operating modes, such as a drilling mode, a hammer drilling mode, or a chiseling or hammering mode. The operator can also use the main switch 26 to vary the rotational speed and/or torque of the electric motor, and thus of the insertion tool 24 or drill chuck 22, which is operatively connected via the striking mechanism. A Human Machine Interface (HMI) 38 provides the operator with a wide range of information about e.g., the charge state of the connected removable battery pack 14, about the set operating mode as well as about any operating faults, e.g. an excessive temperature or the like. Furthermore, the drill hammer 10 comprises an exchangeable communication module 40 for exchanging data with an external device (not shown in detail in this case), e.g. a smartphone, a smart watch, a personal computer, a gateway, a cloud server, or the like. The communication module 40 can also be used to make various settings on the hammer drill 10, e.g. activating or deactivating a kickback control mode or adaptive speed control from the external device. For this purpose, the communication module 40 exchanges the data via radio, in particular WLAN, Bluetooth, LoRa, Zeegbee, or a comparable data protocol. A further detailed description of the processing tool 12 designed as a drill hammer 10 is omitted in this case, as this is only of minor importance regarding the invention, and the drill hammer 10 is also only to be understood by way of example of various handheld processing tools 12.
Between the main handle 28 and the electromechanical battery interface 16 arranged below the main handle 28, the drill hammer 10 comprises a suspension means 42 at its rear end. The suspension means 42 can be functionally divided into an axial displacement region 44, a suspension region 46 extending substantially transverse thereto and a hook-shaped end 48 adjacent to the suspension region 46. The axial displacement region 44 and the suspension region 46 are arranged around at least one contour of the main handle 28 such that the suspension means 42, in a first locking position 50, is inserted into the housing 18 of the drill hammer 10 in a largely surface-neutral manner. The hook-shaped end 48 in the first locking position 50 engages with a first undercut recess 52 of the housing 18. The first undercut recess 52 is designed such that the hook-shaped end 48 for releasing the first locking position 50 is rotated tangentially around the axial displacement region 44 at a relatively small angle, preferably below 10°. Given that, on the one hand, the displacement region 44 is arranged on the right side of the housing 18 or the suspension means 42 when viewed from the rear and the hook-shaped end 48 is arranged on the left side of the housing 18 or the suspension means 42 and, on the other hand, the undercut recess 52 is open towards the top, a tangential clockwise rotation is required to release the suspension means 42 from the first locking position 50. However, this may vary depending on the arrangement and configuration of the suspension means 42 and the undercut recess 52.
For better orientation, coordinate crosses with the designations “rear”, “front”, “bottom”, “top”, “left” and “right” are shown in
By applying pressure to the suspension means 42, in particular to the suspension region 44, against the resilient force of the compression spring 56 in the axial direction A in conjunction with a slight tangential rotation of a few degrees, in particular by less than 10°, in direction TA (see
In the vicinity of the open end 64 of the shank 62, a tangentially extending groove 92 is provided, which on the one hand serves for axial locking in the second locking position 74 and on the other hand also enables tangential locking with different opening angles α. For this purpose, the tangential groove 92 comprises various cup-shaped hollows 94 at the tangential angular distance of the locking opening angles α, in which the ball 88 comes to rest in a locking manner due to the resilient force of the compression spring 86.
In order to prevent the suspension means 42 from being pulled out of the guide bore 54 of the housing 18, it comprises a retaining ring 96 at the open end 64 of the shaft 62, which at the same time also serves as a support for the compression spring 56 (not shown in this case), in particular in the first and third locking positions 50 and 78. The retaining ring 96 can be designed as a snap ring having a guide pin 98, whereby the guide pin 98 prevents axial displacement of the retaining ring 96 by engaging through a corresponding bore 100 of the shaft 62.
In contrast to the previous exemplary embodiment, the leaf spring 114 is no longer fixed in the retaining cover 18, but directly in the housing 18 of the drill hammer 10 without preload. In addition, it is not arranged in the axial direction A, but transversely thereto; in the exemplary embodiment shown in
As in the previous exemplary embodiments, the suspension means 42 is also released in the exemplary embodiments shown in
The leaf spring 114 then acts on the locking geometry 72 of the sliding element 66 or the shaft 62, which is designed as a square such that the suspension means 42 locks tangentially at an opening angle α of 0°, 90°, 180° and 270° in the second locking position 74 when rotated in the direction of TA. Similar to the exemplary embodiment shown in
Finally, it should be noted that the exemplary embodiment shown is not limited to
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 209 180.6 | Aug 2021 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/069056 | 7/8/2022 | WO |
