ELECTRIC HAND TOOL

Description

[0001] The present invention relates to an electric hand-held power tool having the features of the independent claim.

[0002] When using electric handheld power tools, such as impact drills or rotary hammers, significant impact, vibration, and / or rotational forces are generated, which are transmitted to the entire machine housing and the handle. Such impact, vibration, and / or rotational forces have a particularly negative impact on the ergonomics of tool use and, in particular, cause the operator of such a handheld power tool to fatigue very quickly, as their grip and holding power diminishes after a short period of time. Furthermore, such impact, vibration, and / or rotational forces contribute to the rapid wear of sensitive machine components, such as switches, electronics, contact elements, and the like, significantly reducing the service life of the handheld power tool.

[0003] Document US 2014 / 0318821 A1 discloses a hammer drill in which the handle, including the battery, is connected to the rest of the housing via a damping element.

[0004] Document DE 203 17 064 U1 describes a shock-absorbing structure for a pneumatic tool to dampen shocks from an impact unit of the tool.

[0005] Furthermore, publication DE 10 2005 052 428 A1 describes a power tool with a battery. A battery housing is connected to the housing via a vibration damping element, whereby an active damping element can also be used.

[0006] Furthermore, publication DE 102011 002 404 A1 apparently describes a power supply unit for a handheld power tool. The power supply unit is mounted with vibration damping.

[0007] The present invention is therefore based on the object of providing an electric hand-held power tool in which the damping of shock, vibration and / or rotation forces has been optimized.

[0008] The stated object is achieved by an electric hand-held power tool having the features of the independent claim. Further advantageous embodiments and developments of the invention are specified in the respective dependent claims.

[0009] An electric handheld power tool is disclosed, comprising a housing divided into at least two sections. The electric handheld tool has a first section, to which machine elements that generate impact, vibration, or rotational forces are assigned.

[0010] The electric hand tool also has a second section to which machine elements sensitive to impact, vibration or rotation forces are assigned.

[0011] Furthermore, the electric hand-held power tool is provided with a damping system consisting of a plurality of damping elements arranged between the first section and the second section, which damping system absorbs and / or reduces the shock, vibration or rotation loads generated by the machine elements of the first section in at least two, preferably three, spatial directions, so that the second section is designed to be largely low-vibration.

[0012] By designing the second section with low vibration, the sensitive machine elements can be protected from the impact, vibration, or rotational forces acting in at least two, preferably three, spatial directions that are generated and / or induced by the machine elements of the first section. This reduces wear on these highly sensitive machine elements of the first section, thus increasing the longevity of the entire handheld power tool.

[0013] The machine elements of the first section generating impact, vibration and / or rotation forces can in particular generate elongations in at least two, preferably three spatial directions, wherein the generated elongations are largely absorbed by the damping system consisting of several damping elements.

[0014] Furthermore, the present handheld power tool can be provided with an adjustable damping system consisting of multiple damping elements between the first section and the second section. This means that the damping elements provided between the first section and the second section are deliberately selected or arranged in the corresponding handheld power tool to optimally absorb and / or reduce the impact, vibration, or rotational forces generated by the machine elements in at least two, preferably three, spatial directions. The material parameters of the selected damping elements can also be crucial here.

[0015] The impact, vibration, or rotational forces acting in a spatial direction can be defined as an axial force or working direction of the machine tool, a horizontal direction orthogonal to the axial force or working direction, and / or a vertical direction orthogonal to the axial force or working direction. Depending on the application or use of the handheld power tool, the impact, vibration, or rotational forces can propagate in at least two of the three spatial directions mentioned, but usually in all three spatial directions.

[0016] Furthermore, it can be provided that the machine elements of the first section generating impact, vibration or rotation forces comprise at least one drive unit, a gear unit and / or a percussion mechanism of the hand-held power tool or the like.

[0017] The drive unit can be, for example, an electric motor, which can be either a brushless or a brushed motor. The drive unit can be mechanically coupled to the impact mechanism via a gear unit.

[0018] The percussion mechanism itself can, for example, consist of a piston, a firing pin, a striker, and a drive bearing or an eccentric gear. The rotational movements generated and / or produced by the drive unit can be absorbed by the drive bearing, whereby the resulting reciprocating movement can be converted by the piston. A "backward movement" against the axial working or force direction of the piston can generate a negative pressure, which pulls the striker backward. A forward movement of the piston, however, can generate compression, which consequently creates excess pressure between the striker and the piston. The piston and the striker, which move forward at a very high speed, collide with the firing pin.This creates kinetic energy that can be transferred to the striker and the firing pin, with the firing pin transferring this energy to the tool shaft of the hand tool.

[0019] Due to the movements in the electric hand tool described above, high shock, vibration or rotational forces can arise in the first section, which, without a damping system, can be transmitted to the entire hand tool and have a particularly negative effect on the handling and ergonomics of the hand tool.

[0020] Furthermore, the machine elements sensitive to shock, vibration, or rotational loads may include at least one switch for operating the handheld power tool, electrical and / or electronic components, and / or contact elements, or the like. The sensitive machine elements mentioned here may, in particular, be those components that are susceptible to wear and which therefore require protection from the shock, vibration, or rotational forces described above.

[0021] The machine elements of the first section mentioned here that generate shock, vibration or rotation loads and the sensitive machine elements of the second section are not to be understood as limiting, but the present subject matter can also include all other machine elements not explicitly mentioned here that are assigned to the first section and the second section.

[0022] Furthermore, it can be provided that the second section is assigned a battery pack interface to which a battery pack can be electronically and / or mechanically coupled. The battery pack serves to supply the handheld power tool, in particular the drive unit, with electrical energy.

[0023] The battery pack interface of the low-vibration second section can have contact elements and / or retaining elements to which the battery pack can be mechanically and / or electronically coupled. The coupling between the battery pack interface of the second section and the battery pack can be detachable.

[0024] The battery pack can be designed as a removable or replaceable battery pack. In particular, the battery pack can be designed as a removable battery pack or as a system battery pack, which means that the battery pack can be used universally to supply electrical power to various electrical devices, such as power tools, electric garden tools, household appliances, vehicles, or the like, in addition to the electric hand-held tractor.

[0025] The at least one battery pack can comprise at least one battery pack housing, within which at least one battery cell is arranged. The at least one battery cell can be, in particular, a lithium-ion battery cell. Preferably, several battery cells, for example, five or ten battery cells, can also be arranged within the at least one battery pack housing. The several battery cells can be connected to one another in series and / or in parallel.

[0026] The battery pack housing can be constructed in one or more parts. Preferably, the battery pack housing can be constructed in two parts, consisting of a lower part and an upper part. A conductor carrier can be provided within the battery pack housing, which is electrically connected to the at least one battery cell. The electrical conductor carrier is formed by a printed circuit board or circuit board. Various electronic components, such as a button, power MOSFET, etc., are mounted on the electrical conductor carrier. The battery pack can also be equipped with a battery management system.

[0027] The battery pack as such can have a battery pack interface that corresponds to the battery pack interface of the second section. The battery pack interface can be formed by one or more electrical plug-in and / or clamping and / or locking contacts or the like. The one or more plug-in and / or clamping and / or locking contacts can be formed by tulip contacts or sword contacts.

[0028] Due to the low-vibration design of the second section provided by this damping system, the battery pack, and in particular its individual components, can be largely protected from impact, vibration, and rotational forces acting in at least two, preferably three, spatial directions. The low-vibration design of the second section can also have a particularly beneficial effect on the contact between the battery pack interface of the second section and the battery pack, which is significantly more durable and stable due to the low vibration.

[0029] Since the drive unit is assigned to the first section and the battery pack interface with the battery pack that can be coupled to it is assigned to the second section, an electrical connection can be formed between the drive unit and the battery pack interface. The electrical connection can be formed by electrical lines, cables, or the like. This electrical connection can, in particular, be designed and arranged between the first section and the second section in such a way that no transmission of shock, vibration, and / or rotational forces occurs from the first section to the second section.

[0030] As described herein, the damping system is formed from a plurality of damping elements. The damping elements can be formed, for example, by elastic components or the like. The elastic component can be formed, for example, by a rubber element. It is also conceivable for the elastic component to be formed by a spring element or the like. The spring element can be a spring suspension, coil spring, or the like. The damping element is designed as an active damping element. Combinations of the configurations of the individual damping elements within the device are possible.

[0031] The individual damping elements are arranged between the first section and the second section. The individual damping elements are affixed to the first section and / or the second section, at least in sections, on one side. Depending on the design of the damping elements, they can also be affixed to both the first section and the second section.

[0032] The individual damping elements can be attached using friction-locking and / or positive-locking joining techniques, such as adhesive, press-fit, fitting, and / or screw connections. A combination of different joining techniques is also conceivable.

[0033] Furthermore, the second section can have and / or be designed with a handle. Due to the low-vibration second section created by the damping system, the handle, and thus the holding and guiding of the electric hand tool, can also be more comfortable for the operator.

[0034] The electric hand tool can be a hammer drill. Of course, the present damping system can also be transferred and applied to other hand tools, such as impact drills or the like, whereby the impact mechanism would be designed differently.

[0035] The following exemplary embodiment will explain the invention and its advantages in more detail with reference to the attached figure. The relative sizes of the individual elements in the figure do not always correspond to the actual sizes, as some shapes are simplified and others are enlarged relative to other elements for better illustration.

[0036] Fig. 1 shows a schematic side view of the hand tool with a damping system.

[0037] Identical reference numerals are used for identical or equivalent elements of the invention. Furthermore, for the sake of clarity, only those reference numerals are shown in the figure that are necessary for the description of the figure. The illustrated embodiment merely represents an example of how the handheld power tool according to the invention can be configured and does not represent a definitive limitation.

[0038] The Figure 1 shows a schematic side view of an electric handheld power tool 10, in particular a hammer drill 12. The handheld power tool 10 has a housing 14. The housing 14 is divided into at least two sections, in particular a first section 16 and a second section 18.

[0039] The first section 16 is assigned machine elements that generate and / or induce impact, vibration, or rotational forces. These machines that generate impact, vibration, or rotational forces include or at least comprise at least one drive unit 20, a gear unit 22, and / or an impact mechanism 24 of the handheld power tool 10 or the like. The drive unit 20 is formed by an electric motor. The drive unit 20 is mechanically coupled to the impact mechanism 24 via a gear unit. The impact, vibration, or rotational forces generated by the machine elements of the first section 16 can act in at least two, in particular three, spatial directions of the handheld power tool 10.

[0040] The impact, vibration or rotational forces acting in the spatial direction are defined as an axial force or working direction X of the machine tool 10, a horizontal direction orthogonal to the axial force or working direction X and / or as a vertical direction orthogonal to the axial force or working direction X.

[0041] The second section 18, on the other hand, is assigned machine elements sensitive to impact, vibration, or rotational forces. These sensitive machine elements include, among others, a switch 26 for operating the handheld power tool 10, as well as electrical and / or electronic components not shown here, as well as contact elements or the like.

[0042] As is particularly evident from the Figure 1As is clear, the second section 18 also includes a handle 28, or the second section 18 can additionally form a handle 28. The switch 26 is also arranged in the area of ​​the handle 28, so that the operator can operate the switch 26 at the same time while holding the hand-held power tool 10.

[0043] In addition, the second section 18 is assigned a battery pack interface (not shown here), which has contact elements and / or holding elements. A battery pack 30 can be coupled to the battery pack interface both mechanically and electronically. For coupling or connecting the battery pack 30 to the battery pack interface of the second section 18, the latter has a corresponding further battery pack interface. The connection between the battery pack interface and the battery pack 30 can be released at any time. The battery pack 30 is designed as a replaceable or exchangeable battery pack or as a removable battery pack, which means that the battery pack 30 can be used universally for the electrical power supply for various electrical devices, for example a power tool, electric gardening device, household appliance, vehicles or the like, in addition to the electric hand tractor.

[0044] The battery pack 30 comprises a battery pack housing, within which at least one battery cell is arranged. The at least one battery cell can be, in particular, a lithium-ion battery cell. Preferably, several battery cells, for example, five or ten battery cells, can also be arranged within the at least one battery pack housing. The several battery cells can be connected to one another in series and / or in parallel.

[0045] The battery pack housing can be constructed in one or more parts. The battery pack housing is preferably constructed in two parts, consisting of a lower part and an upper part. A conductor carrier is provided within the battery pack housing, which is electrically connected to the at least one battery cell. The electrical conductor carrier is formed by a printed circuit board or circuit board. Various electronic components, such as a button, power MOSFET, etc., are mounted on the electrical conductor carrier. The battery pack is also equipped with a battery management system.

[0046] In order to ensure that the drive unit 20 is supplied with electrical energy, an electrical cable (not shown here) is provided between the battery pack interface and the drive unit.

[0047] In order to protect the sensitive machine elements assigned to the second section 18 as well as the battery pack 30 from the impact, vibration or rotation forces acting in at least two, preferably three spatial directions, a damping system consisting of several damping elements 32 is arranged between the first section 16 and the second section 18.

[0048] The damping elements 32 are arranged between the first section 16 and the second section 18 in such a way that they absorb and / or reduce the shock, vibration or rotation loads generated by the machine elements of the first section 16 in at least two, preferably three, spatial directions, so that the second section 18 is designed to be largely low-vibration.

[0049] Due to a low-vibration design and / or mounting of the second section 18, the sensitive machine elements located there are protected from unnecessarily high loads and / or wear caused by impact, vibration, or rotational forces acting in at least two, preferably three, spatial directions. Furthermore, an operator can hold the handheld power tool 10 significantly longer due to the reduced forces.

[0050] The damping elements 32 of the damping system are preferably formed by elastic components, such as a rubber element, a spring element, or the like. It is also conceivable for the damping element to be designed as an active damping element. Combinations of the individual damping elements within the device are also possible.

[0051] The invention has been described with reference to a preferred embodiment. However, it is conceivable for a person skilled in the art that modifications or variations of the invention can be made without departing from the scope of the following claims. List of reference symbols

[0052] 10Hand tool 12Hammer drill 14Housing 16First section 18Second section 20Drive unit 22Gear unit 24Impact mechanism 26Switch 28Handle 30Battery pack 32Damping element XAxial force or work direction

Claims

1. Electric hand tool (10) comprising a housing (14), wherein the housing (14) is divided into at least two sections, comprising - a first section (16), to which machine elements generating impact, vibratory and / or rotatory forces are assigned, - a second section (18), to which machine elements sensitive to impact, vibratory and / or rotatory stresses are assigned, wherein it is provided that between the first section (16) and the second section (18) a damping system consisting of multiple damping elements (32) is arranged, which absorbs and / or reduces the impact, vibratory and / or rotatory stresses generated by the first section (16) in at least two, preferably three, spatial directions so that the second section (18) is of a widely low-vibration design, characterized in that the individual damping elements (32) • either are fastened to the first section (16) and / or to the second section (18) on one side at least in sections, • or both to the first section (16) as well as to the second section (18) on both sides, and one of the damping elements (32) is designed as active damping element.

2. Electric hand tool according to claim 1, wherein the machine elements of the first section (18), which generate impact, vibratory and / or rotatory forces, generate elongations in the at least two, preferably three spatial directions, wherein the generated elongations are largely absorbed by the damping system consisting of multiple damping elements (32).

3. Electric hand tool according to claim 1 or 2, wherein the spatial directions are defined as axial direction of force (X) of the machine tool, a horizontal direction extending orthogonally to the axial direction of force (X) and / or as a vertical direction extending orthogonally to the axial direction of force (X).

4. Electric hand tool according to any one of the preceding claims, wherein the damping system arranged of multiple damping elements (32) is adjustable between the first section (16) and the second section (18).

5. Electric hand tool according to any one of the preceding claims, in which to the machine elements of the first section (16), which generate the impact, vibratory and / or rotatory forces, at least one drive unit (20), one gear unit (22), and one impact mechanism (24) or the like are comprised.

6. Electric hand tool according to any one of the preceding claims, in which by the machine elements, which are sensitive to impact, vibratory and / or rotatory stresses at least one switch (26) for actuating the hand tool machine, electric and / or electronic components and / or contact elements or the like are comprised.

7. Electric hand tool according to any one of the preceding claims, in which a battery interface, at which a battery pack (30) is capable of being electronically and / or mechanically coupled, is assigned to the second section (18).

8. Electric hand tool according to any one of the preceding claims, in which the damping elements (32) are formed by elastic components or the like.

9. Electric hand tool according to any one of the preceding claims, wherein the second section (18) comprises and / or forms a handle (28).

10. Electric hand tool according to any one of the preceding claims, wherein the electric hand tool (10) is formed by a hammer drill (12).