EP4255672A1

EP4255672A1 - Power tool having a first and a second rechargeable battery

Info

Publication number: EP4255672A1
Application number: EP21814766.8A
Authority: EP
Inventors: Ralf Greitmann; Roland Meuer
Original assignee: Hilti AG
Current assignee: Hilti AG
Priority date: 2020-12-04
Filing date: 2021-11-17
Publication date: 2023-10-11
Also published as: WO2022117337A1; US20240051109A1; CN116529030A; EP4008478A1

Abstract

The present invention relates to a power tool having a first rechargeable battery and a second rechargeable battery as energy sources, the power tool comprising a main body and a motor. The power tool is characterised in particular in that the main body has a first accommodation space for accommodating the first rechargeable battery and a second accommodation space for accommodating the second rechargeable battery, wherein the accommodation spaces are arranged inside a housing of the main body such that the rechargeable batteries are accessible and exchangeable from a rear side of the main body, wherein the accommodation spaces for the rechargeable batteries form a lower termination of the main body of the power tool. Within the meaning of the invention, this means that the accommodation spaces for the rechargeable batteries and the rechargeable batteries themselves are arranged in a lower, rear region of the main body, where they are particularly well-protected from falling out, moisture or the like.

Description

MACHINE TOOL WITH A FIRST AND A SECOND ACCUMULATOR

The present invention relates to a machine tool having a first battery and a second battery as a power source, the machine tool including a main body and a motor. The machine tool is characterized in particular in that the main body has a first accommodation space for accommodating the first rechargeable battery and a second accommodation space for accommodating the second rechargeable battery, the accommodation spaces being arranged within a housing of the main body in such a way that the rechargeable batteries can be viewed from a rear side of the main body are accessible and interchangeable, the receiving spaces for the accumulators form a lower end of the main body of the machine tool. In terms of the invention, this means that the storage spaces for the accumulators or the accumulators themselves are arranged in a lower, rear region of the main body, where they are particularly well protected against falling, moisture or the like.

Background of the invention:

Cut-off grinders or angle grinders are known in the field of machine tools, with which cuts can be made in a substrate to be processed or which can be used to process the surface of a substrate. Such cutting or angle grinders usually have a disc-shaped tool, which is referred to as a cutting or grinding wheel.

Due to the increase in the available capacities in the area of accumulators ("accumulators"), more and more battery or accumulator-operated cut-off machines with cutting discs and blade diameters of more than 230 mm are being launched on the market; This is particularly the case for applications in which petrol cut-off grinders were previously used. Unlike angle grinders, cutting with water to bind dust is an important function of these cut-off grinders. When constructing the devices, care is usually taken to ensure that the batteries and their interface are protected against splashing water when cutting wet. For other applications, such as cutting steel or dry cutting concrete, the batteries and the battery interface should also be protected from metal chips, flying sparks and dust. Furthermore, it is advantageous if the rechargeable batteries, their interface and in particular the contacts of the rechargeable batteries are protected from environmental influences such as rain and moisture.

Machine tools are therefore known in the prior art in which--depending on the structure--the batteries are protected by various housing parts of the machine tool during cutting. Some battery-powered cut-off machines have additional flaps or covers for this purpose, which form a sealed space for the battery. However, it has been shown that cut-off grinders with such additional flaps or covers have some application disadvantages. On the one hand, the additional component can increase the susceptibility of the machine tool to failure. In addition, the flaps or covers often require additional work when changing the battery. In addition, a charging status of the rechargeable battery cannot be displayed directly on the rechargeable battery, since the rechargeable battery is completely enclosed, in particular by the additional cover or the additional flap. With such cut-off grinders, it is often also possible to operate with the flap open or with the cover open, which can then result in an unwanted entry of dust into the battery compartment.

In many other machine tools known from the prior art, the battery pack is arranged in an upper area of the main body of the machine tool. This may enable a certain protection of the machine tool during cutting, but it does not or hardly protects the machine tool and its internal components against the effects of the weather, such as rain or dirty water, which can arise when operating a cut-off machine in wet cutting mode.

The object on which the present invention is based is to overcome the above-described shortcomings and disadvantages of the prior art and to provide a machine tool in which the accumulators and their contacts, interfaces, displays and controls are optimally protected against mechanical damage, for example are protected from falling or from the effects of the weather, such as moisture, rain or moisture. Furthermore, the accumulators should be easily accessible and easily replaceable despite the optimized protection. In this context, experts would welcome it if the best possible protection for the accumulators could be guaranteed without additional flaps or covers having to be provided on the machine tool to protect the accumulators. In addition, the structure of the machine tool and the arrangement of the components should be discussed be as simple, compact and robust as possible within the machine tool and the machine tool should have good ergonomics.

The object is solved by the subject matter of the independent claims. Advantageous embodiments relating to the subject matter of the independent claims can be found in the dependent claims.

Description of the invention:

According to the invention, a machine tool with a first accumulator and a second accumulator is provided as the energy source. The machine tool also has a main body and a motor. The machine tool is characterized in particular in that the main body has a first accommodation space for accommodating the first rechargeable battery and a second accommodation space for accommodating the second rechargeable battery, the accommodation spaces being arranged within a housing of the main body in such a way that the rechargeable batteries can be viewed from a rear side of the main body are accessible and interchangeable, the receiving spaces for the accumulators form a lower end of the main body of the machine tool. In terms of the invention, this means that the storage spaces for the accumulators or the accumulators themselves are arranged in a lower, rear region of the main body, where they are particularly well protected against falling, moisture or the like. It is preferred within the meaning of the invention that the accumulators are arranged in close proximity to an underside and on the rear of the main body of the machine tool, whereby the accumulators are optimally protected against mechanical stresses, such as in the event of a fall, on the one hand, and are optimally protected against moisture on the other , wetness and rain are. Examples of a possible arrangement of the accumulators within the main body of the machine tool are shown in Figs. 1 and 2.

It is preferred within the meaning of the invention that different types of accumulators can be used as the energy source. In this case, both such accumulators can be used which have, for example, a comparatively large volume and a large capacity. However, it can also be preferred that small accumulators with a lower capacity are used. The first and the second rechargeable battery can preferably be of the same type. However, within the meaning of the invention, it can also be preferred that different types of accumulators are used as energy sources. The accumulators used are preferably set up to work together with the same interface on the machine tool. In other words, the machine tool can interface and/or have contact surfaces that can interact with different types of accumulators. This can be achieved, for example, in that the accumulators, which are used as an energy source in the proposed machine tool, have interfaces and/or contact surfaces that are designed to correspond to the interfaces and contact surfaces of the machine tool. The capacity of the accumulators can be between 3 and 15 ampere hours (Ah), for example, and their volume can be between 700 and 1,500 cm ³ , depending on the capacity.

In particular, the invention proposes an arrangement of components for a preferably hand-held, battery-operated cut-off machine with a plurality of rechargeable batteries, preferably two rechargeable batteries. The position of the accumulators (“accumulators”) and the interface for the accumulators is preferably selected in such a way that the accumulators are optimally protected against dust, metal chips, sparks or mud when cutting. Tests have shown that the rechargeable batteries and their interface, as well as their contacts, can be protected particularly effectively against environmental influences, such as rain or moisture, with the invention or the proposed arrangement.

The arrangement of the other assemblies of the machine tool, such as the electronics, motor, handles, gears and cutting disc, is preferably adapted to the position of the accumulators. The proposed arrangement is optimized in particular with regard to robustness, compactness, ergonomics and assembly. In particular, the accumulators are particularly easily accessible, so that they can be exchanged particularly quickly and easily if necessary. In addition, with the proposed arrangement of the batteries in a lower, rear area of the main body of the machine tool, a battery charge indicator is particularly easy to see for the user of the machine tool, so that he is informed about the current charge level of the batteries at all times while the machine tool is in operation. This allows the user to organize work with the cut-off machine well and plan ahead.

It is preferred within the meaning of the invention that the receiving spaces for the accumulators are arranged next to one another. They are preferably constructed similarly to one another or identically. It is preferred within the meaning of the invention that the two receiving spaces for the two accumulators are arranged axially symmetrically to an imaginary longitudinal axis running centrally through the machine tool. In other words, the receiving spaces can be arranged on a right and on a left side of the virtual longitudinal axis of the machine tool. As a result, the structure of the machine tool within its main body can be kept simple and compact. In addition, the compact structure increases the robustness of the proposed machine tool.

The invention with the proposed arrangement of the accumulators in two accommodation spaces, which are preferably arranged next to one another, so that the accumulators are particularly easily accessible from the back of the main body, advantageously enables an optimised, simple design of a battery-operated cut-off machine in which changing the accumulators can be carried out particularly easily. In addition, good protection of the rechargeable batteries and their interface during operation of the machine tool can be guaranteed, as well as good protection against environmental influences such as rain or moisture. The proposed structure of the machine tool, in which the accommodation spaces for the accumulators are arranged in a lower, rear area of the main body, represents a robust and simple device structure and also enables the charge status display of the accumulators to be clearly visible.

It is preferred within the meaning of the invention that the machine tool is a cut-off grinder. The power cutter may include a rear portion formed, for example, by a main body and a protective frame. The main body of the power cutter may be surrounded by a housing and may include a control unit, a drive and/or a drive train and/or a motor. The protective frame can include a front, peripheral handle and a second, upper handle. The front part of the machine tool is formed by its tool, which is a disc-shaped tool, in particular if the machine tool is designed as a cut-off grinder. In particular, it can be referred to as a cutting disk. It is preferred within the meaning of the invention that the spatial directions “front” and “back” are defined by the front area of the machine tool formed by the tool and by the rear area of the machine tool formed by the main body, among other things. The spatial areas "top" and "bottom" or the "top" and "bottom" of the machine tool are preferably defined by the upper handle ("top"), which is preferably also referred to as the second handle within the meaning of the invention, and by the Protective frame, the underside of which preferably runs on the underside of the machine tool.

It is preferred within the meaning of the invention that the machine tool comprises a first, circumferential handle, a second, upper handle and a protective frame for protecting the main body of the machine tool. Details on these components of the machine tool can be found in particular in the figures. The first, circular The handle preferably runs in the area of the transition between the front and rear areas of the machine tool and is usually gripped by the left hand of a right-handed person using the machine tool. In this respect, the first, circumferential handle can also be used to transport the machine tool. Due to the circumferential design of the first handle, the first handle offers effective impact protection on the sides of the machine tool, especially if the machine tool would hit the right or left side of the device if it were to fall. The circumferential configuration of the first handle protects in particular the components of the machine tool arranged in the main body of the machine tool, such as the motor, drive or gearing, but also the accumulators. It is preferred within the meaning of the invention that a plane in which the first handle predominantly runs runs essentially orthogonally to a longitudinal axis of the machine tool. The longitudinal axis, which can be placed conceptually through the machine tool, runs in particular centrally through the device and extends from the front area of the machine tool in the direction of its rear area. It is preferred within the meaning of the invention that the plane in which the first handle predominantly runs is essentially perpendicular to the longitudinal axis of the machine tool.

The second, upper handle preferably runs essentially parallel to the virtual longitudinal axis of the machine tool. This second handle is usually grasped by the right hand of a right-handed person using the machine tool. It is preferred within the meaning of the invention that the upper handle protrudes in a rear spatial direction beyond the main body of the machine tool, so that the main body and its internal components are well protected against a fall and landing of the machine tool on the rear of the device. An overhang is preferably formed by protruding the second handle beyond the rear of the main body of the machine tool. For the purposes of the invention, the term “overhang” preferably describes the distance between a rear wall of the main body of the machine tool, which runs essentially vertically, and a point at the maximum distance from a rear part of the upper handle. This distance or overhang is, for example, in a range from 1 to 12 cm, preferably 3 to 9 cm and particularly preferably about 6 cm.

It is preferred within the meaning of the invention that the second handle is arranged above the electronics of the machine tool and includes actuating switches for the machine tool on its upper side and/or its underside. The fact that the second handle of the machine tool is usually covered by the right hand of a user, the Machine tools are particularly well served by the provision of the actuating switch on the top and/or bottom of the second handle. Due to the preferred physical proximity between the electronics of the machine tool and the at least one actuating switch in the second handle, transmission paths for control commands can be significantly shortened and the amount of wiring and wiring within the device can be simplified or reduced. It is preferred within the meaning of the invention that the area of the second handle that has the at least one actuating switch is referred to as the central part of the upper handle. A longitudinal axis running centrally through the middle part preferably does not run parallel to a surface on which the machine tool can be placed, but inclined at an angle of inclination of 10 to 30 degrees, preferably at an angle of inclination of 15 to 25 degrees and most preferably at an angle of inclination of about 20 degrees. This inclination can significantly improve the ergonomics of the upper handle. The center portion of the top handle is substantially perpendicular to a back portion of the top handle. Thus, this rear part of the upper handle also runs inclined by the above-mentioned angle of inclination of approximately 20 degrees in relation to a rear wall of the main body of the machine tool running essentially vertically. Tests have shown that the inclination of the second handle of the machine tool significantly improves the ergonomics of the machine tool.

In addition, the proposed machine tool includes a protective frame, the underside of which preferably runs on the underside of the machine tool. It is preferred within the meaning of the invention that the protective frame has an L-shaped structure, in particular in a side view of the machine tool. In particular, the lower bar of the “L” runs on the underside of the machine tool, while the bar of the preferably inverted “L” that projects vertically upwards runs along the essentially vertical rear wall of the main body of the machine tool. Such a simple L-structure is preferably present both on the right and on the left side of the machine tool, so that the L-shaped structure is preferably also referred to as “lateral L-shaped structure” within the meaning of the invention. It preferably runs around the main body of the machine tool. The two individual L-shaped structures are preferably connected to one another via a connecting web, the connecting web running through an inner space or reach-through space of the upper handle. According to the invention, it is preferred that the bars of the L-shaped structure of the protective frame, which protrude vertically upwards, form its rear side. The front of the protective frame can preferably also be formed by two vertically projecting beams, which are substantially parallel run to the rear vertically projecting beams of the protective frame. If the protective frame comprises such front-side vertically upwardly projecting beams, the shape of the protective frame can preferably also be referred to as U-shaped, the protective frame preferably comprising two U-shaped structures which are arranged on a right and on a left side of the tool device can and are connected to each other via the connecting web. In terms of the invention, it is preferred that the accumulators are arranged in the interior space formed by the U-shaped or L-shaped structures of the protective frame. In other words, the accumulators can be surrounded by the elements of the protective frame, so that the protective frame optimally protects the accumulators against mechanical damage, for example due to a fall. According to the invention, it is preferred that the accumulators are arranged above the lower bar of the L-shaped or U-shaped structures of the protective frame. The main body of the machine tool is preferably arranged inside the protective frame, the lower end of which is formed by the accumulators.

According to the invention, it is preferred that the accumulators include contacts with which they can be plugged into the machine tool. For this purpose, the power tool includes a corresponding connection arrangement with which the contacts of the accumulators can interact. The machine tool preferably includes an interface with which the energy supply of the device or the energy output of the accumulators can be controlled. It can be preferred within the meaning of the invention that the power tool includes an interface that controls the energy output from both batteries. However, it can also be preferable for the machine tool to have two interfaces, i.e. one interface for each accumulator. According to the invention, it is particularly preferred that the accumulators can be connected to an electronic system of the machine tool via an interface and contacts.

It is preferred within the meaning of the invention that an upper side of the housing of the main body of the machine tool is designed to be inclined in order to ensure a defined drainage of liquid. Preferably, the top of the housing of the main body of the machine tool faces the bottom of the middle part of the upper handle. Like this central part of the handle, the upper side of the housing of the machine tool is preferably designed to be inclined so that rain, dirt or spray water can optimally run off the main body of the machine tool in the “downward” spatial direction. In terms of the invention, it is particularly preferred that the housing of the main body of the machine tool has a backward inclination. For the purposes of the invention, this means that when Placing the machine tool on a surface the front part of the housing of the main body has a greater distance from the ground than the rear part of the housing of the main body of the machine tool. The inclination of the main body of the machine tool can be described by an angle of inclination B, which is preferably formed between an imaginary floor level on which the machine tool can be placed and a plane that is imaginarily laid through the surface of the housing or the main body of the machine tool can. The inclination angle B is preferably in a range of 5 degrees. Tests have shown that an inclined surface of the housing or the main body of the machine tool with an angle of inclination of approximately 5 degrees allows for optimized drainage of rain or protective water.

The housing of the main body of the machine tool can also have ribs to ensure a defined flow of liquid. These ribs discharge the liquid in particular to the side in such a way that the liquid cannot get into the rear area of the machine tool or in the area of the rear side of the main body, where, for example, the operating switch of the accumulators or a charge level indicator of the accumulators can be arranged. By sloping the upper side of the housing of the machine tool main body and/or providing the ribs on the housing of the machine tool main body, it is possible to effectively prevent sensitive components of the machine tool or sensitive components associated with the accumulators from being exposed to moisture, come into contact with moisture or rain and suffer damage as a result.

The proposed machine tool can also be described by an angle of inclination A. This angle of inclination A is preferably formed between an imaginary ground plane on which the machine tool can be parked and a plane that runs centrally through the motor axis and the axis of the cutting disk. It is preferred within the meaning of the invention that this angle of inclination A is in a range between 10 and 30 degrees, preferably in a range between 15 and 25 degrees and particularly preferably around 20 degrees. The angles of inclination A and B are shown in FIG.

It is preferred within the meaning of the invention that the machine tool does not require an additional flap and an additional cover to protect the accumulators from liquid. By avoiding this additional component, which many conventional machine tools have to protect the accumulator, the susceptibility of the machine tool to failure can be significantly reduced. In addition, the effort involved in changing be of the accumulators are reduced because no lid or flap must be held open. Furthermore, by dispensing with the additional covers or flaps, charge status displays can be provided directly on the batteries, which can also be arranged so that the user can see them particularly well, so that the user of the machine tool can get an overview of the charge status of the batteries particularly easily and quickly can get.

It is preferred within the meaning of the invention that the accumulators or their receiving spaces are arranged in the proposed machine tool in the housing of the main body of the machine tool, with the housing forming a sealed space that is tightly closed in particular against dust and/or moisture and moisture is. This effectively prevents unwanted dust entering the battery compartment. The accumulators and their accommodation spaces are located in the housing of the machine tool, in particular in a rear, lower area, i.e. in close proximity to a bottom side and a rear side of the housing of the machine tool.

It is preferred within the meaning of the invention that the machine tool has damping means in order to decouple the handles and the protective frame from vibrations that occur during operation of the machine tool. The damping means preferably comprise springs, with three springs being provided in particular, in order to achieve a decoupling of the handles and the protective frame from the vibrations that occur during operation of the machine tool. Possible attachment locations for the preferably three springs are shown in FIG.

It is preferred within the meaning of the invention that the motor of the machine tool is aligned in the middle, transversely to the accumulators and to the working direction of the machine tool. As a result, the center of gravity of the machine tool is essentially in the center of the motor, so that when the machine tool is operated or carried, the load on the rotating, front handle is as low as possible. In other words, the preferably central arrangement of the motor, whose working axis is preferably perpendicular to a central axis of the machine tool, can provide a particularly well-balanced machine tool that can be carried easily despite its weight and has good ergonomics when cutting.

It is preferred within the meaning of the invention that the machine tool comprises a motor housing, the motor housing comprising a gearbox of the machine tool, a cutting arm for a tool of the machine tool and a means for driving the tool. The means for driving the tool are preferably designed as belts. The strap that Transmission and the cutting arm are shown in FIG. It is preferred within the meaning of the invention that the means for driving the tool runs at least partially parallel to the cutting arm. This essentially parallel arrangement of the cutting arm in relation to the belt for driving the tool of the machine tool is also shown in FIG. It is preferred within the meaning of the invention that the belt is set up to transmit a rotational movement, which is generated in the motor of the machine tool, to the cutting disc of the cut-off grinder and to drive the cutting disc to perform the rotational movement with which the cuts are made in the substrate to be processed can be generated.

It is preferred within the meaning of the invention that the machine tool comprises at least one protective plate for protecting the machine tool and its components on a front side of the housing of the main body of the machine tool. It is particularly preferred within the meaning of the invention that the protective plate forms a lower area of the circumferential first handle, is attached to it or covers it. Preferably, the front of the housing of the main body of the machine tool faces the tool of the machine tool, i.e. preferably the cutting wheel. Dust, metal chips, sparks and/or splashes of mud can hit this front of the main body of the machine tool while being prevented by the protective plate from damaging the machine tool or its main body and its internal components, such as the accumulators. This protective effect is also improved in particular by the fact that the accumulators are arranged in a rear area of the main body, i.e. at a maximum distance from the main impact point of dust, metal chips, sparks and/or mud splashes on the front of the main body of the machine tool. This maximum distance and one possible location of the fender are shown in FIG.

In one embodiment, the invention relates to a battery-powered cut-off machine with two batteries that are accessible from the rear and are preferably completely covered from above. The housing has optimized edges and/or surfaces for a defined water drainage to protect the accumulators and their interface. The other components of the cut-off machine are installed around the accumulators in such a way that the machine tool can be set up easily and that the device is ergonomic.

In particular, the two batteries are well protected from above against environmental influences. This is advantageously achieved by the water drainage provided on the housing, which is made possible in particular by the inclination of the upper side of the main body of the machine tool and/or the provision of the ribs on the housing of the main body of the machine tool. becomes light. In particular, to protect the accumulators from dust, splashing water or metal sparks, a protective plate is provided on the front side of the main body of the machine tool. The provision of the accumulators in a rear, lower area of the main body of the cutting machine grants good access to the accumulators and a good view of an accumulator charge indicator. In addition, the invention enables good protection of the battery interface and in particular the battery contacts.

Further advantages of the invention consist in mounting the electronics of the machine tool in close proximity to the accumulators, as a result of which short transmission paths for the control commands and a reduction in the amount of cabling can be achieved. It is preferred within the meaning of the invention that a central carrier is arranged inside the main body of the machine tool, which is preferably also referred to as a carrier unit. This carrier unit is preferably made of plastic or includes one or more plastics. As a result, the carrier unit can be designed to be very stable on the one hand and particularly light on the other hand, so that it only makes an insignificant contribution to the overall weight of the machine tool. It is preferred within the meaning of the invention that the carrier unit is firmly connected to the motor housing and is set up to accommodate the electronics, the interfaces, the contacts, the accumulators and/or the damping elements. It is preferred in the sense of the invention that the carrier provides an internal structure for the main body of the machine tool, whereby the components of the machine tool provided inside the main body can be fixed to the carrier unit. It is preferred within the meaning of the invention that the protective frame and the upper handle can also be fastened to the carrier unit. The housing of the machine tool can preferably consist of two housing shells, which can also be mounted on the carrier unit.

It is preferred within the meaning of the invention that the carrier, together with the motor housing, represents a central component for the air ducting of the cooling. It is preferred within the meaning of the invention that the electronics of the machine tool are suspended in or on the carrier unit in order to effectively prevent deposits of dust and/or water. The carrier unit can include a heat sink for cooling the electronics, it being possible for an air flow to be guided through the carrier for cooling the electronics. It is preferred within the meaning of the invention that the carrier unit is inclined backwards at an angle of inclination, this angle of inclination of the carrier unit being greater than 3 degrees, preferably in the range of 5 degrees. It is preferred within the meaning of the invention that the angle of inclination is preferably formed between an imaginary floor level on which the machine tool can be parked and a plane which is centrally crossed by the carrier unit of the machine tool. runs. Despite the inclined carrier unit, it is preferred within the meaning of the invention that the interfaces and contacts for connecting the power tool to the accumulators are essentially horizontal. The rechargeable batteries are preferably also aligned essentially horizontally within the machine tool. The term “essentially horizontal” preferably means in the context of the invention that the components mentioned are not inclined in the machine tool, ie that any straight line or plane running through them encloses an angle of essentially 0 degrees with an imaginary subsurface plane. In other words, an imaginary straight line or plane runs through the interfaces, contact surfaces and/or accumulators essentially parallel to an imaginary underground plane.

The inclination of the carrier unit is taken over by the top or outer contour of the machine tool and ensures a particularly favorable water drainage and associated protection of the interfaces and contact surfaces of the accumulators. Additional ribs lead to the drainage of surface water into non-critical areas of the machine tool, so that the interfaces and contact surfaces of the accumulators are optimally protected against moisture.

In addition, the motor of the machine tool is arranged transversely to the batteries. The machine tool preferably includes a motor housing, which in turn has a gearbox, a belt and a cutting arm. The belt as the driving means for the cutting disk preferably works with a transmission ratio of 1:1. A second handle with an actuating switch is preferably arranged above or in close proximity to the electronics of the machine tool. In addition, the power cutter includes a first handle that runs around the power cutter and has an integrated water tap or an integrated water valve. The power cutter also includes a protective frame that runs around the batteries and effectively protects them from knocks or falling. While the protective frame primarily protects the accumulators against a side impact, a rear part of the upper, second handle protrudes beyond the main body of the machine tool, this protruding being referred to as a protrusion. The overhang can, for example, have a length in the range of approx. 6 cm; it primarily protects the machine tool against impact on the rear of the device. The protective frame and the handles of the cut-off machine are preferably decoupled from the vibrations that occur when the cut-off machine is in operation as a result of the rotation of the cut-off wheel. For this purpose, the angle grinder can have damping means, which are formed by springs, for example. A tool for changing the cutting disc can be found on the underside of the tool machine tool with an O-ring. It is preferred within the meaning of the invention that the cutting disk of the proposed cut-off grinder has a blade diameter of greater than 230 mm.

Further advantages result from the following description of the figures. The figures, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into further meaningful combinations.

In the figure, the same and similar components are denoted by the same reference symbols. Show it:

Fig. 1 side and rear view of a preferred embodiment of the proposed machine tool

Fig. 2 side and oblique front view of a preferred embodiment of the proposed machine tool

3 View of a preferred embodiment of the proposed machine tool without accumulators

4 side view of a preferred embodiment of the proposed machine tool without accumulators

5 View of an underside of a preferred embodiment of the proposed machine tool

6 oblique rear view of a preferred embodiment of the proposed machine tool without accumulators, without a gear, without a protective frame and without handles

Fig. 7 Side view of a preferred embodiment of the proposed machine tool as a section with indication of angles and inclination

Execution examples and fiquren description:

Figure 1 shows a side view of a preferred embodiment of the proposed machine tool 1 in the left half of the figure and a rear view of a preferred embodiment of the proposed machine tool 1 in the right half of the figure. The front area of the machine tool 1 is formed by a tool 25 which, in the case of the machine tool shown in Fig 1 is formed by a cutting disc 25 . The tool 25 may be surrounded by a blade guard which may include a water inlet and a handle. The rear area of the machine tool 1 is formed by a main body 4 which has a housing 6 . The main body 4 of the machine tool 1 is surrounded by a protective frame 14 comprising an L-shaped structure 16 . The L-shaped structure 16 preferably comprises a lower area which runs essentially horizontally and which runs on the underside of the housing 6 of the machine tool 1 . In addition, the L-shaped structure 16 can comprise a rear part which runs essentially vertically and which runs along a rear side 9 of the main body 4 of the machine tool 1 . The protective frame 14 preferably comprises two L-shaped structures 16 which are connected to one another on the rear side 9 and on the front handle 12 of the main body 4 of the machine tool 1 via a respective connecting web. Within the meaning of the invention, it is preferred that the protective frame 14 comprises a plastic injection-molded part, which is preferably formed circumferentially and can have a U-profile with ribs.

In addition, the machine tool comprises a front, circumferential handle 12 and an upper, second handle 13. Operating switches 21 can be arranged on the upper, second handle 13, with which the machine tool 1 can be operated. These actuating switches 21 can be arranged in particular on the underside of the second handle 13 . The machine tool 1 can also have a switch-on lock 30 which can preferably be arranged on the upper side of the second handle 13 . It is preferred within the meaning of the invention that the actuating switch 21 can only be actuated if the switch-on lock 30 permits this. It is preferred within the meaning of the invention that the underside of the second handle 13 faces or faces the upper side 10 of the housing 6 of the machine tool 1 . The upper side 10 of the housing 6 is preferably designed to be inclined by 3 to 5 degrees, ie liquid falling on the upper side 10 of the housing 6 is deflected backwards and/or downwards in a spatial direction. This inclination is described by the angle of inclination B (see FIG. 7). The deflection of the liquid is shown in FIG. 1 by the dashed line in the area of the housing 6 of the machine tool 1 . The liquid drainage can be facilitated by the presence of ribs 11 on the housing 6 of the main body 4 of the machine tool 1 can be further improved. Possible arrangements of the ribs 11 are shown in the lower image of FIG.

The ribs 11 preferably represent a raised boundary of the main body 4 of the machine tool 1 . The ribs 11 preferably form a closing edge of the main body 4 of the machine tool 1 , which is arranged, among other things, on the upper side 10 of the housing 6 of the machine tool 1 . Ribs 11 may also form the sides of the main body 4 of the machine tool 1 and the rear closure of the housing 6 of the machine tool 1 . According to the invention, it is preferred that the ribs 11 have a height of up to 2 cm. The ribs 11 can thus be 1.75 cm, 1.33 cm, 1 cm, 0.5 cm, 0.3 cm high, without being limited thereto. It is preferred within the meaning of the invention that the ribs 11 are set up to guide a flow of water, so that dirty water and/or rainwater does not get into the area of sensitive components of the machine tool 1 . Sensitive areas of the machine tool 1 are, for example, the accumulators 2, 3 or their interfaces 18 or contacts 19 or their charge level indicator 31.

The area of the second handle 13 on which the at least one actuating switch 21 is arranged is referred to as the central part of the second handle 13 and is preferably also designed to be inclined. The second handle 13 preferably protrudes beyond a rear side 9 of the main body 4 of the machine tool 1, as a result of which a so-called overhang 17 is formed. As a result, the machine tool 1 and its internal components can be protected particularly well from vibrations and impacts that act on the machine tool 1 from the rear side 9 of the main body 4 . In other words, the overhang 17 of the second handle 13 protects the machine tool 1 particularly well if it threatens to fall onto its back 9 if it falls down.

The overhang 17 also has the further advantage that the distance between the two handles 12, 13 increases, so that the handling of the machine tool 1 can be improved and made safer.

In a front area of the main body 4 of the machine tool 1, the motor 5 is arranged. A protective plate 28 can be arranged on a front side 27 of the housing 6 of the machine tool 1, which protects the main body 4 and its internal components from dust, flying sparks, dirt or splashing water or metal chips. In a rear, lower area of the main body 4 of the machine tool 1 are the accumulators 2, 3 of the machine tool 1, which supply the machine tool 1 with energy. They therefore serve as an energy source for the machine tool 1. The first accumulator 2 is present in a first exception space 7 , while the second accumulator 3 is located in a second receiving space 8 . The arrangement of the accumulators 2, 3 in the receiving spaces 7, 8 within the main body 4 of the machine tool 1 can also be seen clearly in the right half of FIG.

A protective plate 28 can be arranged on a front side 27 of the housing 6 of the machine tool 1, which protects the main body 4 and its internal components from dust, flying sparks, dirt or splash water or metal chips. The front side 27 of the housing 6 of the machine tool 1, as well as the protective plate 28, which is present on the front side 27 of the housing 6 of the machine tool 1, is also shown in particular in FIG. It is preferred within the meaning of the invention that the protective plate 28 is fastened to the front, surrounding handle 12 or forms part of this front handle 12 . The trajectories of possible objects against which the protective plate 28 is intended to protect the hand-held power tool 1 are also shown in FIG. 2 (see arrows at the bottom left). The protective plate 28 is preferably made of metal or another fireproof material in order to be able to protect the machine tool 1 from hot sparks in particular. According to the invention, it is preferred that the front side 27 of the housing 6 of the machine tool 1 faces or is arranged opposite the tool 25 of the machine tool 1 . In particular, Fig. 2 shows a side view of a preferred embodiment of the proposed machine tool 1 in the left half of the image and an oblique front view of the proposed machine tool 1 in the right half of the image.

Fig. 3 shows a rear view of a preferred embodiment of the proposed machine tool 1 without accumulators 2, 3. The protective frame 14 is shown, as well as the first handle 12 and the second handle 13. The main body 4 of the machine tool 1 is preferably located within the protective frame 14 with its housing 6, the accumulators 2, 3 and their receiving spaces 7, 8 being arranged inside the main body 4 of the machine tool 1. In particular, the accumulators 2, 3 and their accommodation spaces 7, 8 are located in a rear, lower area of the main body 4 of the machine tool 1. The housing 6 of the main body 4 of the machine tool 1 includes a rear side 9 which forms the rear end of the main body 4 of the machine tool 1 . The charge status display 31 of the accumulators 2, 3 is clearly visible from behind below the housing 6 and behind the protective frame 14 of the machine tool 1. Due to the batteries 2, 3 not shown in FIG. 3, the interface 18 and the contacts 19 for the batteries 2, 3 can be seen in FIG.

The interface 18 and the contacts 19 for the accumulators 2, 3 are also shown in FIG. 4, which shows a side view of a preferred embodiment of the proposed machine tool 1 without accumulators 2, 3. The electronics 20 of the machine tool 1 are arranged above the interface 18 and above the contacts 19 for the accumulators 2, 3, the electronics 20 being in close proximity to the actuating switches 21 on the second handle 13 of the machine tool 1 in order to provide transmission and communication paths to keep short. Provision is also made for the electronics 20 to be in close proximity to the accumulators 2, 3; this also to shorten the transmission and communication paths. The electronics 20 are preferably held by a central carrier 32 which is preferably also referred to as a carrier unit 32 . It is preferred within the meaning of the invention that the carrier unit 32 is firmly connected to the motor housing 22 and is set up to support the electronics 20, the interfaces 18, the contacts 19, the accumulators 2, 3 and/or the damping elements 15 of the machine tool 1 record. It is particularly preferred within the meaning of the invention that the carrier 32 forms an inner structure for the main body 4 of the machine tool 1, which can carry or accommodate the components of the machine tool 1 mentioned.

Also shown in FIG. 4 is the motor 5 of the machine tool 1 , which is arranged in a front area of the main body 4 of the machine tool 1 . The motor 5 has an axis which is essentially orthogonal to a longitudinal axis 29 of the machine tool 1 . In other words, the axis of the motor 5 of the machine tool 1 is preferably perpendicular to the longitudinal axis 29 of the machine tool 1 . For the purposes of the invention, this arrangement is described with the wording that the motor 5 of the machine tool 1 is aligned transversely to the accumulators 2, 3 of the machine tool 1. The axis of the motor protrudes practically out of the plane of the drawing in FIG. 4 and its position is also shown in FIG. FIG. 5 also shows a possible position of the imaginary longitudinal axis 29 of the machine tool 1 (see top right in FIG. 5). The motor housing 22 can have air outlets from which the used cooling air can be blown out of the interior of the machine tool 1 . In particular, 22 slots can be provided on the underside and / or rear of the motor housing, from which the cooling air is blown out.

Fig. 5 shows the view of an underside of a preferred embodiment of the proposed machine tool 1. In a front area of the main body 4 of the machine tool 1 the motor 5 is arranged. It is surrounded by a motor housing 22 . The movement generated by the motor 5 of the machine tool 1 is transmitted to the tool 25 of the machine tool 1 via drive means 26 . A gear 23 of the machine tool is arranged between the drive means 26 and the motor 5 and is preferably also arranged inside the motor housing 22 . The drive means 26 may comprise or be formed by a belt. The cutting disc 25 of the power cutter 1 is connected to the main body 4 of the power cutter 1 via a cutting arm 24 , the belt 26 for transmitting the movement of the motor 5 of the power cutter 1 running at least partially parallel to the cutting arm 24 . The accumulators 2, 3 are not shown in FIG. Due to their omission, one can see the battery interface 18 and the connection contacts 19, which electrically or electronically connect the batteries 2, 3 to the machine tool 1.

Fig. 6 shows an oblique rear view of a preferred embodiment of the proposed machine tool 1 without accumulators 2, 3, without gearing 23, without protective frame 14 and without handles 12, 13. In particular, Fig. 6 shows the damping means 15 with which the protective frame 14 and the handles 12, 13 can be decoupled from the vibrations that occur during operation of the machine tool 1. The damping means 15 preferably comprise springs or the damping means 15 are formed by springs. According to the invention, it is preferred that the machine tool 1 has three damping means 15 or springs for decoupling oscillations and vibrations. This effectively prevents the vibrations from being transmitted to the user, in particular his hands, arms and shoulders, so that longer and healthier work with the machine tool 1 is possible. In addition, FIG. 6 shows the carrier unit 32 which is arranged inside the main body 4 of the machine tool 1 .

7 shows the angle of inclination A between the motor and the cutting axis, as well as the angle of inclination B by which the surface 10 of the housing 6 of the machine tool 1 is inclined. The angle of inclination A can be between 10 and 30 degrees, for example, while the angle of inclination B is around 5 degrees.

1 machine tool

2 first accumulator

3 second accumulator

4 main body

5 engine

6 housing

7 first recording room

8 second recording room

9 Rear of the main body

10 Top of Case

11 ribs

12 first, surrounding handle

13 second, upper handle

14 protective frame

15 damping means

16 L-shaped structure

17 overhang

18 Interface between accumulators and machine tool

19 Contacts between accumulators and machine tool

20 electronics of the machine tool

21 operating switch

22 motor housing

23 gears 24 cutting arm

25 tool or cutting disc

26 drive means or belts

27 Front of the case

28 fender

29 Longitudinal axis of the machine tool

30 power on lock

31 charge indicator

32 carrier unit

A Inclination angle between motor and cutting axis

B Inclination of the surface of the main body of the machine tool

Claims

Machine tool (1) with a first accumulator (2) and a second accumulator (3) as an energy source and a main body (4) and a motor (5), characterized in that the main body (4) has a first receiving space (7) for Has receptacles for the first accumulator (2) and a second accommodation space (8) for accommodating the second accumulator (3), the accommodation spaces (7, 8) being arranged within a housing (6) of the main body (4) in such a way that the accumulators (2, 3) are accessible and interchangeable from a rear side (9) of the main body (4), the accommodation spaces (7, 8) for the accumulators (2, 3) forming a lower end of the main body (4) of the machine tool (1 ) form. Machine tool (1) according to Claim 1, characterized in that an upper side (10) of the housing (6) of the main body (4) of the machine tool (1) is designed to be inclined in order to ensure a defined flow of liquid. Machine tool (1) according to Claim 1 or 2, characterized in that the housing (6) of the main body (4) of the machine tool (1) has ribs (11) in order to ensure a defined flow of liquid. Machine tool (1) according to one of the preceding claims, characterized in that the machine tool (1) does not require an additional flap and an additional cover to protect the accumulators (2, 3) from liquid. Machine tool (1) according to one of the preceding claims, characterized in that the machine tool (1) has a first, circumferential handle (12), a second, upper handle (13) and a protective frame (14) for protecting the main body (4)

23 of the machine tool (1). Machine tool (1) according to Claim 5, characterized in that the machine tool (1) has damping means (15) in order to protect the handles (12, 13) and the protective frame (14) from vibrations which arise during operation of the machine tool (1). decouple. Machine tool (1) according to Claim 5 or 6, characterized in that the protective frame (14) has an L-shaped structure (16). Machine tool (1) according to one of Claims 5 to 7, characterized in that the second handle (13) protrudes in a rear spatial direction beyond the main body (4) of the machine tool (1) and thus forms an overhang (17). Machine tool (1) according to one of the preceding claims, characterized in that the motor (5) of the machine tool (1) is aligned transversely to the accumulators (2, 3). Machine tool (1) according to one of the preceding claims, characterized in that the machine tool (1) is a cut-off grinder. Machine tool (1) according to one of the preceding claims, characterized in that the accumulators (2, 3) can be connected to electronics (20) of the machine tool (1) via an interface (18) and contacts (19). Machine tool (1) according to claim 11, characterized in that the second handle (13) above the electronics (20) of the machine tool (1) for the machine tool (1) includes.

13. Machine tool (1) according to one of the preceding claims, characterized in that the machine tool (1) comprises a motor housing (22), the motor housing (22) having a gearbox (23) of the machine tool (1), a cutting arm (24) for a tool (25) of the machine tool (1) and at least one means (26) for driving the tool (25).

14. Machine tool (1) according to claim 13, characterized in that the at least one means (26) for driving the tool (25) of the machine tool (1) runs at least partially parallel to the cutting arm (24).

15. Machine tool (1) according to one of the preceding claims, characterized in that the machine tool (1) has at least one protective plate (28) on a front side (27) of the housing (6) of the main body (4) of the machine tool (1) to protect the Machine tool (1) includes.