Hand-held power tool having an energy storage device detachly fixed to

Abstract

The invention relates to a hand-held power tool, in particular an impact hammer, having a tool receiving device (1) for a tool arranged along an impact axis (X), a drive device for a tool subsequently accommodated in a machine housing (2), and a handle (3) arranged on the machine housing (2) opposite the tool receiving device (1), 8a; 8b) for the power source, which is removably secured to the machine housing (2); 8b), at least one housing recess (7a; 7b) extending transversely to the impact axis (X) being provided in the region of the machine housing (2). 7b) for the exchangeable accommodation of the energy storage device (8a; 8b), the energy storage device (8a; 8b) are arranged such that the total center of gravity in the radial direction with respect to the impact axis (X) lies within the lateral dimension of the drive device.

Description

Field of the Invention

[0001] The present invention relates to a hand-held power tool, in particular a percussion hammer, having a tool receiving device for the tool arranged along an impact axis X, a drive device for the tool subsequently accommodated in a housing, and a handle arranged on the machine housing opposite the tool receiving device, wherein at least one energy storage device is provided which is detachably fixed relative to the machine housing and which is used to supply electrical energy to the drive device.

[0002] The field of application of the present invention extends to cordless (i.e., battery-powered) hand-held power tools, in particular so-called in-line type hand-held power tools. The individual components of the tool receiving device, the machine housing, and the handle usually arranged thereon are oriented along the impact axis in order to effectively apply the required manual pressure to a chisel as the tool and to enable the hand-held power tool concerned to be operated as precisely as possible. At least one replaceable energy storage device of the power supply must be arranged on or in the body housing so as to be accessible from the outside. However, it is also conceivable to apply the solution according to the invention to other battery-powered power tools, wherein the energy storage device will be integrated with the power tool to optimize the installation space. The energy storage device includes a housing usually made of plastic and having electrical contacts, and a plurality of rechargeable battery cells are accommodated in the housing and electrically connected to each other. The energy storage device is a relatively sensitive and safety-related component of the hand-held power tool. If damage occurs, an exothermic reaction may cause damage in individual cases, and this must be taken into account when positioning the energy storage device relative to the rest of the hand-held power tool. Background Art

[0003] JP 2016 165784 A discloses a general hand-held power tool having an in-line design. A tool receiving device, a machine housing for vibration-damped accommodation of the drive device, and a handle molded onto the rear of the machine housing are arranged along the tool axis. In the inner region of the handle, the energy storage devices are arranged adjacent to each other on the housing end face adjacent to the internal drive device such that the energy storage devices do not interfere with the functionality of the handle. In this way, the energy storage devices can be accessed for replacement, and this placement does not cause too much interference to the in-line design. However, if there is a defect, there remains a risk of injury to the operator's hand.

[0004] US 5 208 525 A shows a power supply arrangement structure for a cordless device, and a battery device partially formed in the shape of a machine housing is detachably attached to the machine housing with this power supply arrangement structure. In contrast to the above prior art, the detachable attachment occurs within the region of the handle, on the outer side of the handle. However, for a handheld power tool, this prior disclosure only includes such non-in-line types of drilling tools and sawing tools. Instead, the region of the handle specifically projects radially from the tool axis, which provides support against the machine torque on the operator side if it is a drilling tool, but at the same time also exacerbates the vibration characteristics of the handheld power tool.

[0005] DE 29 513 651 U1 discloses a battery-powered handheld power tool, in which a recess for completely accommodating a battery device is integrated in the handle of the handheld power tool. The energy storage device is detachably connected to the part of the machine housing forming the handle by means of a snap-fastener. The problem with this technical solution is that the installation space in the handle region of the machine housing is limited and only energy storage devices with a very small energy capacity and corresponding small dimensions can be accommodated in such regions.

[0006] The object of the present invention is to further improve a general type of cordless handheld power tool, which is particularly designed in an in-line configuration, such that on the one hand, one or more energy storage devices with a larger energy capacity that can be detachably fixed thereto are arranged to be easily replaceable thereon, and on the other hand, the operation of the tool is improved. Summary of the Invention

[0007] This object is achieved by a handheld power tool of the general type according to claim 1 in combination with its characterizing features. The following dependent claims describe advantageous developments of the present invention.

[0008] The present invention includes the following technical teachings: The machine housing of a handheld power tool with an in-line design is provided with at least one housing recess extending transversely to the impact axis X, and the at least one housing recess is for removably accommodating at least one energy storage device, wherein the energy storage device is arranged such that the total center of gravity relative to the impact axis X is within the lateral dimension of the drive device.

[0009] In other words, at least one energy storage device is positioned within a certain accuracy range in the region of the impact axis X such that the distance of the total center of gravity in the radial direction from the impact axis X may not be greater than the geometric dimension of the drive device in the radial direction, specifically, if the handheld power tool is designed as a hammer drill, not greater than the diameter of the impact mechanism.

[0010] Advantageously, in this way, the weight of at least one energy storage device does not significantly change the overall center of gravity. This results in improved vibration characteristics in all directions and thus in an improved operation of the hand-held power tool designed according to the invention, specifically in terms of the user being able to easily manually guide the chisel and rotate the hand-held power tool about the impact axis X without having to expend too much effort.

[0011] At least one housing recess for receiving one or more energy storage devices is preferably arranged between the drive device and the handle inside the machine housing relative to the impact axis X. This is because in this case sufficient installation space can be created by extending the housing even for relatively large energy storage devices or a plurality of energy storage devices. The arrangement of the housing recess between the drive device and the handle also enables the energy storage device to be accommodated in such a way that it is protected from critical loads. The internal position of the electrical connection contacts also protects them from damage and contamination. In addition, in the presence of adjacent structural devices, this arrangement of the housing recess enables the shortest possible internal machine wiring length, which allows higher currents to be obtained with a smaller cross-section. This also improves the electromagnetic compatibility of the hand-held power tool.

[0012] According to a first preferred embodiment, the housing recess can be accessed from the lower side and / or the upper side of the machine housing, such that the assigned energy storage device can be inserted into the housing recess from below or from above. According to the invention, the dimensions of the housing of the energy storage device are determined relative to the geometric dimensions of the housing recess such that it completely accommodates the energy storage device in order to achieve the above-mentioned technical advantages.

[0013] According to a second preferred embodiment, this can also be achieved by arranging the housing recess on one of the flank sides of the machine housing, such that the energy storage device can be inserted laterally into it. Specifically, the left-side arrangement on the machine housing enables a right-handed user gripping the handle of the machine housing with the right hand to attach or remove the energy storage device with the left hand.

[0014] The housing recess according to the invention can also optionally extend continuously through the machine housing, i.e., in terms of the above-mentioned preferred embodiments, continuously from the top to the bottom or laterally extending transversely thereto. The energy storage device can be attached or removed from both sides through opposite recess openings, such that the right-handed limitation given in the above example can be eliminated.

[0015] However, within the framework of a continuous housing recess, it is also conceivable to insert the energy storage device from each recess opening, in which case it can even extend radially beyond the machine housing, since such an arrangement has a compensating effect on the overall center of gravity.

[0016] Preferably, at least one energy storage device is arranged relative to the machine housing such that it can be placed entirely within a housing recess. The at least one energy storage device is symmetrically positioned relative to two machine planes A and B that are arranged perpendicular to each other. The machine planes A and B coincide with the impact axis X of the hand-held power tool on the intersection line. Machine plane A forms a vertical plane relative to the hand-held power tool, and machine plane B, which is arranged transversely to this vertical plane, forms a horizontal plane relative to the hand-held power tool in the horizontal holding position of the hand-held power tool. Description of the Drawings

[0017] Other measures for improving the present invention will be explained in more detail below with reference to the drawings in connection with the description of the preferred exemplary embodiments of the present invention. In the drawings: Figure 1 A perspective view of a hand-held power tool showing different alternative arrangements of energy storage devices thereon, and Figure 2 A perspective view of the same hand-held power tool illustrating the positions of machine planes A and B. Detailed Description of the Invention

[0018] According to Figure 1 , a battery-powered hand-held power tool designed as a percussion hammer basically consists of a tool receiving device 1 and a housing 2. The tool receiving device is arranged along the impact axis X for detachably attaching a chisel (not further shown) as a tool. The housing follows a radial direction for accommodating the internal drive device of the tool (not visible herein). If it is a percussion hammer, the drive device includes a common combination of an electric motor with a gearbox and a percussion mechanism.

[0019] Axially opposite to the tool receiving device 1, a handle 3 is arranged on the machine housing 2, which is designed to be directly molded onto the machine housing 2.

[0020] In this exemplary embodiment, the machine housing 2 consists of three parts and is composed of a front housing part 4, an intermediate housing part 5, and a rear housing part 6. The front housing component 4 is assigned to the tool receiving device 1, and the rear housing part 6 is assigned to the handle 3.

[0021] The intermediate housing part 5 of the machine housing 2 has a vertical housing recess 7a that extends transversely to the impact axis X for removably accommodating an energy storage device 8a. The assigned energy storage device 8a can be arranged in the housing recess 7a such that the total center of gravity relative to the impact axis X lies within the lateral dimensions of the drive device. This means that the total center of gravity of the hand-held power tool relative to the impact axis X does not change outside the lateral dimensions of the internal drive device when the energy storage device is mounted.

[0022] In combination with this exemplary embodiment, an alternative variant is also illustrated, by means of which the housing recess extends at a right angle from the flank side of the machine housing relative to the above-described vertical housing recess 7a. The accumulator device 8b can be accommodated in such a horizontally extending housing recess 7b and can be mounted and removed from the side. In contrast, the housing recess 7a is arranged on the lower side and / or the upper side of the machine housing 2.

[0023] Both the vertical housing recess 7a and the horizontal housing recess 7b can extend continuously through the machine housing, thereby forming recess openings opposite to each other.

[0024] The housing recess 7a or 7b arranged in the region of the intermediate housing part 5 of the machine housing 2 is arranged relative to the impact axis X between, on the one hand, the drive device of the tool receiving device 1 and, on the other hand, the handle 3 in an interior adjacent manner.

[0025] The accumulator devices 8a; 8b each have a plastic housing 9 in which the electrical contacts 10 made of plastic material are located, and these electrical contacts are connected inwardly to a rechargeable battery unit (not visible herein) accommodated in the plastic housing 9.

[0026] The accumulator device 8a or 8b can be completely fixed within the assigned housing recess 7a or 7b by means of a one-handed removable clamping mechanism.

[0027] Figure 2 The positions of the vertical machine plane A and the horizontal machine plane B relative to the impact axis X are illustrated. The intersection line between the two machine planes A and B lies on the impact axis X. In this regard, the continuous housing recess 7a in the intermediate housing part 5 is symmetrically positioned relative to both the machine plane A and the machine plane B. The accumulator device 8a removably fixed therein is also symmetrically arranged relative to the assigned housing recess 7a and the two machine planes A and B, such that the total center of gravity in the radial direction relative to the impact axis X lies within the lateral dimension of the internal drive device according to the invention.

[0028] The present invention is not limited to the above-described exemplary embodiment. On the contrary, modifications thereof are also conceivable, and these modifications are covered by the scope of protection of the following claims. For example, as long as the position of the total center of gravity relative to the impact axis X does not exceed the limitation according to the invention, more than one accumulator device can also be accommodated in the housing recess.

[0029] List of reference numerals 1 Tool receiving device 2 Machine housing 3 Handle 4 Front housing part 5 Intermediate housing part 6 Rear housing part 7 Housing recess 8 Energy storage device 9 Plastic housing 10 Electrical contact X Impact axis A Vertical machine plane B Horizontal machine plane

Claims

1. A hand-held power tool, in particular a percussion hammer, having a tool receiving device (1) for the tool arranged along an impact axis (X), a drive device for the tool subsequently accommodated in a machine housing (2), and a handle (3) arranged on the machine housing (2) opposite the tool receiving device (1), wherein, A power supply provides at least one energy storage device (8a; 8b) detachably fixed to the machine housing (2). It is characterized in that at least one housing recess (7a; 7b) extending transversely to the impact axis (X) is provided in the region of the machine housing (2), and the at least one housing recess is used for replaceably accommodating the energy storage device (8a; 8b), wherein the energy storage device (8a; 8b) is arranged such that the total center of gravity in the radial direction with respect to the impact axis (X) is within the lateral dimension of the drive device.

2. The hand-held power tool according to claim 1 It is characterized in that The housing recess (7a) is arranged on the lower side and / or the upper side of the machine housing (2).

3. The hand-held power tool according to claim 1 Characterized in that, The housing recess (7b) is arranged on one of the flank sides of the machine housing (2).

4. The hand-held power tool according to any one of the preceding claims Characterized in that, The housing recesses (7a; 7b) continuously extend through the machine housing (2) such that two recess openings opposite to each other are formed.

5. The hand-held power tool according to any one of the preceding claims It is characterized in that The housing recesses (7a; 7b) are arranged inside the machine housing (2) between the internal drive device and the handle (3) with respect to the impact axis (X).

6. The hand-held power tool according to any one of the preceding claims It is characterized in that The impact axis (X) extends on the intersection line of two machine planes (A, B) arranged at right angles to each other, wherein the energy storage device (8a; 8b) is symmetrically positioned with respect to the two machine planes (A, B).

7. The hand-held power tool according to any one of the preceding claims It is characterized in that, The energy storage device (8a; 8b) is completely fixed within the housing recess (7a; 7b) by means of a detachable clamping mechanism that can be operated with a single hand.

8. The hand-held power tool according to any one of the preceding claims It is characterized in that The drive device accommodated in the machine housing (2) includes an electric motor having a downstream impact mechanism.

9. The hand-held power tool according to any one of the preceding claims It is characterized in that The handle (3) is designed to be directly molded onto the machine housing (2).

10. The hand-held power tool according to any one of the preceding claims It is characterized in that The energy storage device (8a; 8b) has a plastic housing (9) in which at least one rechargeable battery cell is accommodated.

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