Hand-held grinder

Abstract

In order to provide a hand-held grinder that enables easy grinding with as little fatigue as possible, according to the invention the grinding machine comprises a holding device for holding the grinding machine, a drive motor, a motor housing for the drive motor, and a tool head, wherein: the holding device comprises a substantially tubular rod having a proximal end and a distal end; the motor housing and the drive motor disposed therein are disposed at the proximal end, and the tool head is disposed at the distal end; the rod of the holding device is in the form of a single-chamber rod in which a drive shaft for driving the tool head and a flow region for a suction device are provided.

Description

[0001] Handheld grinder

[0002] The present invention relates to a hand-held grinding machine, in particular a so-called long-neck grinder.

[0003] Hand-held grinding machines are known, for example, from DE 102005 021 153 A1, WO 2008 / 033377 A2 or US 2006 / 0073778 A1.

[0004] The object of the present invention is to provide a hand-held grinding machine which enables simple and, if possible, fatigue-free grinding.

[0005] This object is achieved by a hand-held grinding machine according to claim 1. According to the invention, the tubular rod of the holding device is designed as a single-chamber rod in which a drive shaft for driving the tool head and a flow area for a suction device are provided.

[0006] The tubular rod is specifically intended to connect the tool head and the motor housing.

[0007] By designing the tubular rod as a single-chamber rod, both the drive shaft for driving the tool head and the flow area for extracting dust and abrasion generated during operation of the grinding machine can be arranged together within a chamber formed by the single-chamber rod.

[0008] The single-chamber rod, in particular, allows for a reduced weight of the tubular rod. This allows for simple and fatigue-free grinding with the grinding machine.

[0009] As a single-chamber rod, the tubular rod can also be manufactured cost-effectively. The drive shaft is, in particular, a flexible shaft. Such a flexible shaft can be bent with a certain bending radius, deviating from a linear axis of rotation. The flexible shaft can transmit torque in a bent state.

[0010] A further development of the grinding machine can provide that the rod comprises an interior space in which the flow region is formed and through which the drive shaft runs at least in sections.

[0011] In particular, the chamber formed by the single-chamber rod forms the interior of the tubular rod.

[0012] The interior of the tubular rod preferably extends along the entire length of the tubular rod. This means that the interior of the tubular rod advantageously extends from the distal end of the tubular rod to the proximal end within the tubular rod.

[0013] At the distal end and / or at the proximal end of the tubular rod, the latter may have a frontal opening through which access to the interior of the tubular rod is formed.

[0014] An advantageous further development of the grinding machine can provide that the rod is designed as a single-walled tube.

[0015] The tubular rod preferably has a round, oval, elliptical, or elongated O-shaped cross-section. Likewise, the tubular rod can also have a triangular, square, or polygonal cross-section, preferably with rounded edges.

[0016] Preferably, a wall thickness of the tubular rod is smaller than a free inner cross section of the tubular rod.

[0017] It can be provided that the wall thickness of the tubular rod is approximately 5 mm or less. For example, the wall thickness of the tubular rod can be approximately 3 mm or less.

[0018] For example, a wall thickness of the tubular rod may be about 2 mm or less.

[0019] The term “approximately” can, for example, mean a deviation of + / - 10%, preferably + / - 20%, from the specified value.

[0020] Additionally or alternatively, a wall thickness of the tubular rod may be about 0.5 mm or more.

[0021] For example, a wall thickness of the tubular rod may be about 0.75 mm or more.

[0022] For example, a wall thickness of the tubular rod may be about 1 mm or more.

[0023] It can be provided that a wall thickness of the tubular rod is between about 0.5 mm and about 5 mm.

[0024] For example, a wall thickness of the tubular rod may be between about 0.75 mm and about 3 mm.

[0025] For example, a wall thickness of the tubular rod may be between about 1 mm and about 2 mm.

[0026] For example, a wall thickness of the tubular rod may have a thickness of

[0027] 1.2 mm + / - 20% or 1.2 mm + / - 10% or 1.2 mm + / - 5%.

[0028] The inner cross-section of the tubular rod can, for example, have a diameter of 60 mm or less, preferably 50 mm or less, particularly preferably about 33 to about 45 mm. The extended length of the tubular rod can be about 1000 mm or less.

[0029] For example, the extension length of the tubular rod may be about 850 mm or less.

[0030] For example, the extension length of the tubular rod may be about 700 mm or less.

[0031] Additionally or alternatively, it may be provided that the extension length of the tubular rod is approximately 300 mm or more.

[0032] For example, the extension length of the tubular rod may be about 450 mm or more.

[0033] For example, the extension length of the tubular rod can be about 600 mm or more.

[0034] It may be provided that the extension length of the tubular rod is between about 300 mm and about 1000 mm.

[0035] For example, the extension length of the tubular rod may be between about 450 mm and about 850 mm.

[0036] For example, the extension length of the tubular rod can be between about 600 mm and about 700 mm.

[0037] For example, the extension length of the tubular rod can be 680 mm + / - 20% or 680 mm + / - 10% or 680 mm + / - 5%.

[0038] A further embodiment of the grinding machine can provide for the rod to be made of a fiber composite material, in particular a carbon fiber composite material. By forming the tubular rod from the fiber composite material, in particular the carbon fiber composite material, it can be designed with a particularly low weight. This can reduce the overall weight of the grinding machine, making grinding significantly easier and significantly less tiring.

[0039] It may be provided that the weight of the tubular rod is about 250 g or less.

[0040] For example, the weight of the tubular rod may be about 200 g or less.

[0041] For example, the weight of the tubular rod can be about 175 g or less.

[0042] Additionally or alternatively, the weight of the tubular rod may be approximately 75 g or more.

[0043] For example, the weight of the tubular rod can be about 100 g or more.

[0044] For example, the weight of the tubular rod can be about 125 g or more.

[0045] It may be provided that the weight of the tubular rod is between about 75 g and about 250 g.

[0046] For example, the weight of the tubular rod can be between about 100 g and about 200 g.

[0047] For example, the weight of the tubular rod can be between about 125 g and about 175 g.

[0048] For example, the weight of the tubular rod may be 152 g + / - 20%, 152 g + / - 10%, or 152 g + / - 5%. The total weight of the grinder may be approximately 3500 g or less.

[0049] For example, the total weight of the grinder can be about 3250 g or less.

[0050] For example, the total weight of the grinder can be about 3000 g or less.

[0051] Additionally or alternatively, the total weight of the grinding machine may be approximately 2000 g or more.

[0052] For example, the total weight of the grinder can be about 2250 g or more.

[0053] For example, the total weight of the grinder can be about 2500 g or more.

[0054] The total weight of the grinding machine may be between approximately 2000 g and approximately 3500 g.

[0055] For example, the total weight of the grinder can be between about 2250 g and about 3250 g.

[0056] For example, the total weight of the grinder can be between about 2500 g and about 3000 g.

[0057] For example, the total weight of the grinder can be 2900 g + / - 20% or 2900 g + / - 10% or 2900 g + / - 5%.

[0058] It may be provided that a ratio of the weight of the tubular rod to the total weight of the grinding machine is about 0.1 or less.

[0059] For example, the ratio of the weight of the tubular rod to the total weight of the grinding machine may be approximately 0.08 or less. For example, the ratio of the weight of the tubular rod to the total weight of the grinding machine may be approximately 0.06 or less.

[0060] Additionally or alternatively, it may be provided that a ratio of the weight of the tubular rod to the total weight of the grinding machine is about 0.02 or more.

[0061] For example, a ratio of the weight of the tubular rod to the total weight of the grinding machine may be about 0.03 or more.

[0062] For example, a ratio of the weight of the tubular rod to the total weight of the grinding machine may be about 0.04 or more.

[0063] It may be provided that a ratio of the weight of the tubular rod to the total weight of the grinding machine is between about 0.02 and about 0.1.

[0064] For example, a ratio of the weight of the tubular rod to the total weight of the grinding machine may be between about 0.03 and about 0.08.

[0065] For example, a ratio of the weight of the tubular rod to the total weight of the grinding machine may be between about 0.04 and about 0.06.

[0066] For example, the ratio of the weight of the tubular rod to the total weight of the grinding machine can be 0.05 + / - 20% or 0.05 + / - 10% or 0.05 + / - 5%.

[0067] In particular, by forming the tubular rod from the carbon fiber composite material, an optimized haptic experience can be achieved for a user of the grinding machine, since the carbon fiber composite material, especially in comparison to a metallic material, provides a warm and non-slip surface when gripping.

[0068] Advantageously, an inner wall of the tubular rod, facing the interior of the tubular rod, can be provided with antistatic properties and / or coated with a non-stick coating. This can prevent or at least minimize the adhesion of dust and abrasion particles generated during use of the grinding machine and extracted through the flow area of ​​the tubular rod.

[0069] Particularly preferably, the grinding machine can be provided with electrical contact between the fibers of the fiber composite material in the rod in order to establish an electrical connection, in particular an earthing connection, between the tool head and the motor housing.

[0070] In particular, the fibers of the fiber composite material can be contacted at the proximal end and / or distal end of the rod in order to form the electrical connection, in particular the grounding, between the tool head and the motor housing.

[0071] Since the carbon fibers of the carbon fiber composite material, in particular, exhibit electrically conductive properties, they can become statically charged during operation of the grinding machine due to the dust and abrasion particles flowing along the inner wall. Electrical contact, especially grounding, can prevent static charging of the rod, preventing dust and abrasion particles from adhering to the inner wall of the rod.

[0072] In a further development of the grinding machine, a discharge section for discharging a flow from the flow region can be provided at the proximal end of the rod.

[0073] The discharge section is provided in particular to discharge the flow flowing from the tool head through the flow area of ​​the tubular rod together with the dust and abrasion generated by the operation of the grinding machine from the flow area.

[0074] The discharge section, in particular, provides for a flow guide from the tubular rod to an outer side. A further advantageous embodiment of the grinding machine can provide for the discharge section to comprise a flow passage formed in a wall of the rod, and preferably for a lateral flow discharge from the flow region to be provided through the flow passage.

[0075] Through the flow passage, a flow connection can be formed between the interior of the tubular rod and the outside of the rod to divert the flow from the flow area.

[0076] By forming the flow passage in the wall of the rod, the flow can be discharged laterally from the interior of the rod.

[0077] The flow passage can thus provide for a deflection of the flow flowing in the flow area of ​​the tubular rod to the outside of the rod.

[0078] In a further development of the grinding machine, a connection device for connecting a suction device can be formed on the discharge section.

[0079] The extraction device is preferably a portable or stationary extraction device, in particular a vacuum cleaner.

[0080] The suction device can be coupled to the connection device of the discharge section, for example by means of a plug connection and / or snap connection.

[0081] Preferably, a coupling element of a hose or pipe of the suction device can be detachably connected to the connection device of the discharge section.

[0082] Advantageously, the grinding machine can be provided with the discharge section comprising at least one discharge element arranged at the proximal end of the rod and providing flow guidance from the flow region into the flow passage. The discharge element is preferably arranged at the proximal end of the rod, at least partially within the interior of the rod.

[0083] The discharge element can be formed as a molded part and / or an injection-molded part or the like.

[0084] Preferably, the discharge element can be formed from a fiber composite material.

[0085] Particularly preferably, the discharge element can be formed from a carbon fiber composite material.

[0086] Alternatively, the discharge element can also be made of a plastic or a metallic material.

[0087] The discharge element is particularly designed to effect a flow deflection by which the flow flowing essentially linearly through the flow region in the tubular rod is deflected in order to be discharged laterally through the flow passage in the tubular rod.

[0088] An embodiment of the grinding machine can also provide that the flow guide from the flow region into the flow passage is formed by a discharge slope of the at least one discharge element facing the interior of the rod.

[0089] The discharge slope facing the interior of the rod, i.e. the flow area in the rod, preferably has an orientation by which the flow flowing through the flow area in the tubular rod is deflected in the direction of the flow passage provided laterally in the wall of the rod in order to discharge the flow laterally from the interior of the rod.

[0090] Furthermore, a further development of the grinding machine can provide for the at least one discharge element to be inserted into the proximal end of the rod or to be plugged onto the proximal end of the rod. For example, the discharge element can be plugged into the proximal end of the rod in the shape of a plug.

[0091] The exit slope can form an inclined front side of the exit element, which is aligned with the interior of the tubular rod by inserting or plugging the exit element into or onto the proximal end of the rod.

[0092] Advantageously, the discharge element of the grinding machine can have antistatic properties.

[0093] Preferably, the discharge element is made of a material that has antistatic properties.

[0094] It can also be provided that at least the discharge slope of the discharge element is provided with antistatic properties or is coated with an antistatic coating.

[0095] Advantageously, the discharge element, preferably the fibers of the fiber composite material, in particular the carbon fibers, can be electrically contacted.

[0096] By electrically contacting the fibers of the discharge element, an electrical connection, in particular an earthing, of the discharge element can be formed in order to prevent static charging of the discharge element due to the flow of dust and abrasion flowing along it.

[0097] In addition, an embodiment of the grinding machine can provide that the at least one discharge element is attached to the motor housing or is at least partially formed integrally with the motor housing.

[0098] The discharge element can thus be designed as a separate component that is attached to the motor housing and / or the proximal end of the tubular rod.

[0099] Likewise, the discharge element can be formed at least partially integrally as a section of the motor housing, or as a section of a part of the motor housing. The tubular rod can be placed on the discharge element or inserted into it if the tubular rod and the motor housing are coupled together.

[0100] In a further development of the grinding machine, the at least one discharge element can comprise a drive shaft passage through which the drive shaft is guided from the motor housing into the interior of the rod.

[0101] Preferably, it can be provided that the drive shaft passage extends through the discharge slope.

[0102] The drive shaft passage can advantageously comprise a bearing for the drive shaft, for example in the form of a plain bearing or rolling bearing.

[0103] The drive shaft passage can therefore form a radial bearing for the drive shaft.

[0104] The drive shaft passage may include or form a seal that provides a fluidic seal between the interior of the rod and the motor housing. This can prevent the flow containing dust and abrasion debris from the flow area of ​​the tubular rod from entering the motor housing.

[0105] Advantageously, in the grinding machine, the drive shaft can be provided with a casing, preferably made of rubber, a plastic or the like, at least in the interior of the rod, and the casing can have a friction-minimizing guide, preferably made of a PTFE material or the like, for the drive shaft.

[0106] The sheathing can protect the drive shaft from dust and abrasion in the interior or flow area of ​​the rod and / or provide guidance or bearing for the drive shaft.

[0107] The sheath is preferably made of rubber or plastic.

[0108] In particular, the sheath has antistatic properties. A friction-minimizing guide can be provided on the inner side of the sheath facing the drive shaft.

[0109] Particularly when the flexible shaft is bent, the friction-minimizing guide can enable low-friction rotation of the shaft.

[0110] The friction-minimizing guide can be made, for example, from a PTFE material or the like.

[0111] It can be provided that the grinding machine, in particular a drive motor of the grinding machine, has a power consumption of approximately 1000 W or less.

[0112] For example, the grinding machine, in particular a drive motor of the grinding machine, can have a power consumption of approximately 800 W or less.

[0113] For example, the grinding machine, in particular a drive motor of the grinding machine, may have a power consumption of approximately 600 W or less.

[0114] Additionally or alternatively, it can be provided that the grinding machine, in particular a drive motor of the grinding machine, has a power consumption of approximately 200 W or more.

[0115] For example, the grinding machine, in particular a drive motor of the grinding machine, can have a power consumption of approximately 300 W or more.

[0116] For example, the grinding machine, in particular a drive motor of the grinding machine, may have a power consumption of approximately 400 W or more.

[0117] It can be provided that the grinding machine, in particular a drive motor of the grinding machine, has a power consumption between approximately 200 W and approximately 1000 W. For example, the grinding machine, in particular a drive motor of the grinding machine, can have a power consumption between approximately 300 W and approximately 800 W.

[0118] For example, the grinding machine, in particular a drive motor of the grinding machine, can have a power consumption of between approximately 400 W and approximately 600 W.

[0119] For example, the grinding machine, in particular a drive motor of the grinding machine, can have a power consumption of 500 W + / - 20% or 500 W + / - 10% or 500 W + / - 5%.

[0120] It may be provided that a ratio of the total weight of the grinding machine to the power consumption of the grinding machine is approximately 17.5 kg / kW or less.

[0121] For example, a ratio of the total weight of the grinder to the power consumption of the grinder may be about 12.5 kg / kW or less.

[0122] For example, a ratio of the total weight of the grinder to the power consumption of the grinder can be about 7.5 kg / kW or less.

[0123] Additionally or alternatively, it may be provided that a ratio of the total weight of the grinding machine to the power consumption of the grinding machine is approximately 2 kg / kW or more.

[0124] For example, a ratio of the total weight of the grinder to the power consumption of the grinder can be about 3 kg / kW or more.

[0125] For example, a ratio of the total weight of the grinder to the power consumption of the grinder can be about 4 kg / kW or more.

[0126] It can be provided that the ratio of the total weight of the grinding machine to the power consumption of the grinding machine is between approximately 2 kg / kW and approximately 17.5 kg / kW. For example, the ratio of the total weight of the grinding machine to the power consumption of the grinding machine can be between approximately 3 kg / kW and approximately 12.5 kg / kW.

[0127] For example, a ratio of the total weight of the grinder to the power consumption of the grinder can be between about 4 kg / kW and about 7.5 kg / kW.

[0128] For example, the ratio of the total weight of the grinder to the power consumption of the grinder can be 5.8 kg / kW + / - 20% or 5.8 kg / kW + / - 10% or 5.8 kg / kW + / - 5%.

[0129] Further preferred features and / or advantages of the invention are the subject of the following description and the drawings of exemplary embodiments.

[0130] In the figures shows:

[0131] Fig. 1 is a schematic perspective view of a handheld

[0132] Grinding machine, with a view of a top side of the grinding machine;

[0133] Fig. 2 is a schematic sectional view of a tool head of the

[0134] grinding machine;

[0135] Fig. 3 is a schematic sectional view of a connecting portion between a holding device and a flexible pipe element of the grinding machine;

[0136] Fig. 4 is a schematic sectional view of a motor housing of the

[0137] grinding machine;

[0138] Fig. 5 is a schematic perspective sectional view of the motor housing of the grinding machine in Fig. 4; Fig. 6 is a further schematic perspective sectional view of the

[0139] Motor housing of the grinding machine in Fig. 4;

[0140] Fig. 7 is a schematic perspective detail sectional view of a

[0141] Connecting section between the holding device and the motor housing;

[0142] Fig. 8 is a schematic sectional view of a housing inlet for a

[0143] Power cable of the grinder;

[0144] Fig. 9 is a schematic perspective view of the housing inlet according to Fig. 8 with the power cable in a pre-fixed arrangement;

[0145] Fig. 10 is a schematic perspective view of the enclosure inlet with the power cable in a fixed arrangement.

[0146] Identical or functionally equivalent elements are provided with the same reference numerals in all figures.

[0147] Figures 1 to 10 show an embodiment of a handheld sander, designated as a whole by 100, which is also referred to as a long-neck sander. With such a sander 100, large surfaces, especially wall surfaces, ceiling surfaces, and floor surfaces, can be processed easily and conveniently.

[0148] The grinding machine 100 has a tool head 102 which includes a tool holder 104 for receiving a machining tool 106, for example an abrasive.

[0149] The tool head 102 is pivotally mounted on a holding device 110 of the grinding machine 100 by means of a pivoting device 108.

[0150] The pivoting device 108 comprises a fork element 112 and a pivoting element 116 arranged on the fork element 112 so as to be pivotable about a pivot axis 114. The pivoting element 116 is designed, for example, as a pivot ring 118, as can be seen in particular in Fig. 2.

[0151] By means of the pivot ring 118, the fork element 112 is pivotally connected to a housing 120 of the tool head 102.

[0152] The fork element 112, the pivot element 116 and the housing 120 of the tool head 102 are connected to one another in such a way that the tool head 102 can be pivoted relative to the fork element 112 about two pivot axes 114 which are aligned substantially perpendicular to one another.

[0153] The holding device 110 of the grinding machine 100 comprises a tubular rod 122 which has a proximal end 124 facing the user in the use state and a distal end 126 facing away from the user in the use state.

[0154] The fork element 112 and the tool head 102 arranged thereon are provided at the distal end 126 of the tubular rod 122 of the holding device 110.

[0155] A motor housing 128 of the grinding machine 100 is arranged at the proximal end 124 of the tubular rod 122 of the holding device 110.

[0156] A drive motor 130 of the grinding machine 100 is accommodated in the motor housing 128 of the grinding machine 100.

[0157] A handle element 132 is provided on the motor housing 128, by which a user can grip the grinding machine 100.

[0158] The drive motor 130 is coupled to the tool holder 104 by means of a flexible shaft 134 (drive shaft), so that the tool holder 104 with the machining tool 106 arranged thereon can be driven in particular in a rotating, oscillating and / or eccentric manner.

[0159] The flexible shaft 134 extends at least partially within the tubular rod 122. In addition, the flexible shaft 134 extends at least partially in a flexible tube element 136, by means of which the tubular rod 122 is coupled to the housing 102.

[0160] For optimized weight distribution of the grinding machine 100, the drive motor 130 is preferably arranged on a side of a central axis 138 of the tubular rod 122 opposite the tool head 102.

[0161] When the grinding machine 100 is in use, the user can grip the handle element 132 and the tubular rod 122 of the holding device 110 of the grinding machine 100, for example, to carry out a machining operation.

[0162] In order to provide an action radius within which the user, starting from a predetermined standing position, can reach a surface to be machined with the tool head 102, for example for machining high ceilings, an extension element 140 can be arranged on the motor housing 128 or the handle element 132.

[0163] The extension element 140 can be releasably attached to the grinding machine 100, in particular to the motor housing 128 or the handle element 132 of the grinding machine 100.

[0164] The extension element 140 comprises in particular a tubular rod 142, which preferably forms an extension of the tubular rod 122 of the holding device 110 of the grinding machine 100.

[0165] In Fig. 3, a schematic detailed view of a connecting section 144 between the holding device 110 and the flexible tube element 136 of the grinding machine 100 is shown in a longitudinal section.

[0166] The connecting portion 144 comprises a sleeve element 146 on which two opposite insertion portions 148 are formed.

[0167] On one side, an end of the flexible tube element 136 opposite the tool head 102 and, on the opposite side, the distal end 126 of the tubular rod 122 are inserted into the insertion sections 148 of the sleeve element 146 in order to couple them together.

[0168] Fastening devices 152 can be provided on the sleeve element 146, which are each assigned to the insertion sections 148 of the sleeve element 146.

[0169] The fastening devices 152 may comprise fastening means, for example screws, pins, locking elements or the like, for coupling, preferably releasably coupling, the tubular rod 122 and the flexible tube element 136 to the sleeve element 146.

[0170] A guide device 150 for the flexible shaft 134 is provided in the sleeve element 146. This guide device 150 forms a guide for the flexible shaft 134 to guide it from the tubular rod 122 into the flexible tube element 136.

[0171] The guide device 150 forms a bearing for the flexible shaft 134. The guide device 150 may, for example, comprise a plain bearing or a rolling bearing, by means of which the flexible shaft 134 is rotatably mounted in a radial direction.

[0172] The sleeve element 146 has a cavity 154 in its interior, through which a flow connection is formed between an interior space 160 of the tubular rod 122 and an interior space of the flexible tubular element 136, which will be discussed in more detail below.

[0173] The flexible shaft 134 extends in particular within this cavity 154 of the sleeve element 146.

[0174] Fig. 4 shows a schematic sectional view of the motor housing 128 of the grinding machine 100 and Figs. 5 and 6 each show further schematic perspective sectional views of the motor housing 128 shown in Fig. 4 from different viewing directions.

[0175] A connecting portion 156 is provided on the motor housing 128 to couple the proximal end 124 of the tubular rod 122 to the motor housing 128. The tubular rod 122 is inserted with the proximal end 124 into the connecting portion 156 on the motor housing 128.

[0176] A fastening device 158 may be provided on the connecting portion 156 to fasten the tubular rod 122 to the motor housing 128.

[0177] The fastening device 158 may comprise a plurality of fastening means, for example screws, pins, locking elements or the like, in order to fasten the tubular rod 122 to the motor housing 128, preferably to fasten it releasably.

[0178] The tubular rod 122 is designed in particular as a single-chamber rod.

[0179] A single-chamber rod means that an interior space 160, preferably only a single interior space 160, is formed in the tubular rod 122, which extends from the proximal end 124 of the tubular rod 122 to the distal end 126 of the tubular rod 122.

[0180] Openings are provided at the proximal end 124 of the tubular rod 122 and at the distal end 126 of the tubular rod 122 through which the interior space 160 is accessible from both ends 124, 126.

[0181] Preferably, the tubular rod 122 designed as a single-chamber rod is a single-walled tube.

[0182] The tubular rod 122 may, for example, have a round, oval, elliptical or elongated O-shaped cross-section.

[0183] Likewise, the tubular rod 122 may have a triangular, square or polygonal cross-section, preferably with rounded edges.

[0184] In particular, the tubular rod 122 is formed from a fiber composite material, preferably a carbon fiber composite material. To minimize adhesion properties of the tubular rod 122, at least the interior space 160 of the tubular rod 122 can be provided with antistatic properties or coated with an antistatic and / or anti-adherent coating.

[0185] In particular, the fibers of the fiber composite material are electrically contacted at the proximal and distal ends 124, 126 of the rod 122, so that an electrical connection, in particular a grounding, is formed between the tool head 102 and the motor housing 128.

[0186] In particular, carbon fibers of the carbon fiber composite material exhibit electrically conductive properties, so that the rod can become statically charged due to the dust and abrasion particles flowing along the inner wall. This can be prevented by electrical contact, particularly grounding, to prevent dust and abrasion particles from adhering to the flow area 162 within the rod 122.

[0187] The grinding machine 100 includes a suction channel 164 that extends from the tool head 102 to the proximal end 124 of the tubular rod 122.

[0188] Through the suction channel 164, dust and abrasion generated in the area of ​​the tool head 102 during operation of the grinding machine 100 can be removed and disposed of through the suction channel 164.

[0189] The flexible tube element 136 and the tubular rod 122 form flow sections of the suction channel 164.

[0190] In particular, the flow region 162 is formed by the interior 160 of the tubular rod 122, which forms a flow section of the suction channel 164.

[0191] At the proximal end 124 of the tubular rod 122, a discharge section 166 is provided through which a flow S flowing through the flow region 162, i.e., the extracted dust and debris, can be discharged or extracted. A connection device 168 is formed on the discharge section 166, through which a suction device (not shown in detail), in particular a vacuum cleaner, can be coupled to the discharge section 166. As a result, the dust and debris generated during operation can be extracted through the suction channel 164 and disposed of.

[0192] The discharge section 166 is designed in particular in such a way that a lateral discharge of the flow S from the flow region 162 of the tubular rod 122 is provided.

[0193] Advantageously, the discharge section 166 is arranged on a side of the central axis 138 of the tubular rod 122 opposite the drive motor 130 or on the same side as the tool head 102 with respect to the central axis 138 of the tubular rod 122.

[0194] The discharge section 166 includes a flow passage 170 formed in the wall of the tubular rod 122.

[0195] The flow passage 170 is formed as an opening or recess in the wall of the tubular rod 122.

[0196] Advantageously, the flow passage 170 can be formed in such a way that the recess extends in a slot-like manner from the proximal end 124 of the tubular rod 122 towards the distal end 126 of the tubular rod 122.

[0197] Preferably, the flow passage 170 is arranged on a side of the central axis 138 of the tubular rod 122 opposite the drive motor 130 or, with respect to the central axis 138 of the tubular rod 122, on the same side as the tool head 102.

[0198] The discharge section 166 includes a discharge element 172 inserted into the interior space 160 of the tubular rod 122 at the proximal end 124 of the tubular rod 122. This discharge element 172 may be attached to the motor housing 128 or formed integrally with the motor housing 128.

[0199] The discharge element 172 can be formed as a molded part and / or an injection-molded part or the like.

[0200] The discharge element 172 is preferably made of a fiber composite material, in particular a carbon fiber composite material. Likewise, the discharge element 172 can be made of a plastic or metal.

[0201] Advantageously, the discharge element 172, in particular the fibers of the fiber composite material, are electrically contacted to form an electrical connection, in particular a grounding connection, to the discharge element 172. This can prevent static charging of the discharge element 172 due to the dust and abrasion flowing along it.

[0202] The discharge element 172 is configured such that it is inserted into the proximal end 124 of the rod 122. For example, the discharge element 172 can be inserted into the interior space 160 of the rod 122 at the proximal end 124 of the rod 122 in a plug-like manner.

[0203] Alternatively, the discharge element 172 can also be plugged or placed onto the proximal end 124 of the rod 122.

[0204] Preferably, the interior space 160 of the rod 122, i.e., the flow region 162 within the interior space 160 of the rod 122, is fluid-tightly sealed by the outlet element 172 toward the proximal end 124 of the tubular rod 122. The flow S flowing in the flow region 162 of the rod 122 is thereby prevented from flowing into the interior of the motor housing 128.

[0205] The discharge element 172 forms a flow guide in the flow region 162 of the rod 122, through which the flow S flowing in the flow region 162 is guided from the flow region 162 into the flow passage 170. For this purpose, a discharge slope 174 is formed on the discharge element 172, which is oriented such that it faces the flow region 162 of the rod 122.

[0206] Through this discharge slope 174, the flow S impinging on the discharge element 172, in particular the dust and abrasion generated and extracted in the area of ​​the tool head 102 during operation of the grinding machine 100, is guided from the flow area 162 into the flow passage 170 in order to be discharged from the flow area 162 of the rod 122 via the discharge section 166.

[0207] The discharge slope 174 extends from a wall section of the tubular rod 122 opposite the flow passage 170 at an inclined angle to a rear section of the flow passage 170 as seen in the flow direction.

[0208] The discharge slope 174 thus extends from the wall section of the tubular rod 122 opposite the flow passage 170 at the inclined angle through the interior space 160 of the tubular rod 122 to the rear section of the flow passage 170.

[0209] Advantageously, the discharge slope 174 merges essentially flush into the flow passage 170.

[0210] In this way, the lateral flow discharge from the flow region 162 into the discharge section 166 is formed.

[0211] A drive shaft passage 176 is also formed on the outlet element 172, through which the flexible shaft 134 is guided from the interior 160 of the tubular rod 122 into the motor housing 128.

[0212] The drive shaft passage 176 extends in particular through the discharge bevel 174 of the discharge element 172. The drive shaft passage 176 can have a bearing, for example a plain bearing or roller bearing, by which the flexible shaft 134 is radially mounted.

[0213] In particular, the drive shaft passage 176 forms a seal or includes a sealing element to form a fluid-tight connection between the interior 160 of the rod 122 and the motor housing 128.

[0214] In the grinding machine 100, it is particularly provided that the flexible shaft 134 runs through the flow region 162 of the tubular rod 122.

[0215] This means that in the tubular rod 122 designed as a single-chamber rod, both the flow region 162 for extracting the dust and abrasion and the flexible shaft 134 for driving the tool head 102 are provided in the same interior space 160 of the rod 122.

[0216] To protect and / or guide the drive shaft 134, it has a sheath 178 in the interior space 160 of the rod 122. This sheath 178 is preferably made of rubber or a plastic.

[0217] The sheath 178 can extend into the drive shaft passage 176 at the proximal end 124 of the rod 122 and abut against a peripheral surface 182 of the drive shaft passage 176. This can, for example, form a seal between the flow region 162 of the rod 122 and the motor housing 128.

[0218] The casing 178 has a friction-minimizing guide 180 inside, through which the flexible shaft 134 is guided with low friction. The friction-minimizing guide 180 can be formed, for example, from a PTFE material or the like.

[0219] Fig. 8 shows a schematic sectional view of a housing inlet 184 of the motor housing 128 of the grinding machine 100. This housing inlet 184 is provided for passing a power cable 186 into the motor housing 128, in particular to supply power to the drive motor 130 of the grinding machine 100. The housing inlet 184 comprises a housing inlet section 188, which is formed integrally with the motor housing 128 and through which the power cable 186 is passed.

[0220] Preferably, the housing inlet 184 has a circular passage cross-section.

[0221] One or more engagement portions 192 are formed on an inner wall portion 190 of the housing inlet portion 188. The engagement portion 192 is configured such that a projection 194 on a sleeve 196, in particular a rubber sleeve, which surrounds the power cable 186 at least in the region of the housing inlet 184, engages therein in order to fix the sleeve 196 to the motor housing 128.

[0222] The sleeve 196 is preferably provided to provide a seal to the interior of the motor housing 128 and / or a kink protection for the power cable 186 passing through the housing inlet 184.

[0223] The housing inlet 184 includes a cable fixation 198, which is provided inside the motor housing 128 corresponding to the housing inlet section 188.

[0224] The cable fixation 198 comprises a clamping device 200 and a fixing device 202.

[0225] Preferably, the clamping device 200 and the fixing device 202 are arranged substantially one behind the other in an insertion direction of the power cable 186 through the housing inlet 184.

[0226] During assembly of the motor housing 128, the power cable 186 is first passed through the housing inlet 184 of the motor housing 128 and inserted into the clamping device 200 and the fixing device 202, as shown in Fig. 9. The clamping device 200 is configured to include two clamping elements 204 arranged at a distance from one another. Preferably, the clamping elements 204 are arranged parallel to one another or at a slightly inclined angle to one another.

[0227] In particular, the clamping elements 204 are arranged at a distance from one another which is slightly smaller than a diameter of the power cable 186, so that the power cable 186 can be clamped between the clamping elements 202.

[0228] The clamping elements 204 spaced apart from one another are preferably formed integrally with the motor housing 128, in particular with a housing shell of two or more housing shells of the motor housing 128, for example a lower or a right housing shell of the motor housing 128.

[0229] To assemble the motor housing 128, the power cable 186 can be pre-fixed in this way, ie it is first passed through the housing inlet section 188 and then clamped between the clamping elements 202 of the clamping device 200 in a defined position.

[0230] The fixing device 202 comprises a plurality of fixing elements 206 which are provided in pairs corresponding to one another.

[0231] In the embodiment shown in Fig. 8, for example, three pairs of fixing elements 206 are arranged one behind the other in the insertion direction of the power cable 186. Likewise, only two pairs of fixing elements 186 (Figs. 9 and 10) or more than three pairs of fixing elements 206 can be provided.

[0232] The fixing elements 206 are preferably formed integrally with the motor housing 128.

[0233] In particular, it is provided that in each case one fixing element 206 of a pair of fixing elements 206 is formed integrally with a housing shell of the motor housing 128, for example the lower or the right housing shell of the motor housing 128, and the respective other fixing element 206 of the pair of fixing elements 206 is formed integrally with the other housing shell of the motor housing 128, for example the upper or the left housing shell of the motor housing 128.

[0234] The pairs of fixing elements 206 provided corresponding to one another are designed in such a way that in an assembled configuration of the motor housing 128 for the power cable 186 a fixing area is formed between the fixing elements 206.

[0235] For this purpose, each pair of fixing elements 206 is designed in such a way that recesses 208 are formed on the fixing elements 206 that are opposite one another.

[0236] The recesses 208 on the fixing elements 206 can be V-shaped, semicircular or the like.

[0237] The fixing area for fixing the power cable 186 between the fixing elements 206 is formed by the opposing recesses 208 of the respective pair of fixing elements 206.

[0238] In particular, the V-shaped, semicircular or similar recesses 208 of the respective pair of fixing elements 206 ensure that a passage cross-section of the fixing area formed between the fixing elements 206 is successively reduced as the motor housing 128 is assembled and, in the final assembled configuration of the motor housing 128, has a slightly smaller passage cross-section than the cross-section of the power cable 186.

[0239] In this way, in the assembled configuration of the motor housing 128, ie for use with the grinding machine 100, the power cable 186 is fixed in a stationary position by a press fit between the fixing elements 206.

[0240] The cable fixing device 198 designed in this way is therefore provided to first pre-fix the power cable 186 in a defined position for mounting the motor housing 128 by means of the clamping device 200, in order to then be able to easily assemble the housing shells of the motor housing 128 by means of the pre-fixed and thus positioned power cable 186 and to fix the power cable 186 in place by means of the fixing device 202.List of reference symbols Grinding machine Tool head Tool holder Machining tool Swivel device Holding device Fork element Swivel axis Swivel element Swivel ring Housing Tubular rod Proximal end Distal end Motor housing Drive motor Handle element Flexible shaft Flexible tubular element Central axis Extension element Tubular rod Connecting section Sleeve element Inserting section Guide device Fastening device Cavity Connecting section Fastening device Interior Flow area Suction channel Discharge section.

[0241] Connection device

[0242] Flow passage

[0243] Discharge element

[0244] Exit slope Drive shaft passage Sheath Friction-minimizing guide Circumferential surface Housing inlet

[0245] Power cable

[0246] Housing inlet section

[0247] Interior wall section

[0248] Intervention section

[0249] projection

[0250] sleeve

[0251] Cable fixation

[0252] clamping device

[0253] Fixing device

[0254] clamping element

[0255] Fixing element

[0256] recess

[0257] Flow direction

Claims

Patent claims 1. Hand-held grinding machine (100), comprising - a holding device (110) for holding the grinding machine (100), - a drive motor (130), - a motor housing (128) for the drive motor (130) and - a tool head (102), wherein the holding device (110) comprises a substantially tubular rod (122) having a proximal end (124) and a distal end (126), wherein the motor housing (128) and the drive motor (130) arranged therein are arranged at the proximal end (124), and wherein the tool head (102) is arranged at the distal end (126), characterized in that the rod (122) of the holding device (110) is designed as a single-chamber rod in which a drive shaft (134) for driving the tool head (102) and a flow region (162) for a suction device are provided.

2. Grinding machine according to claim 1, characterized in that the rod (122) comprises an interior space (160) in which the flow region (162) is formed and through which the drive shaft (134) extends at least in sections.

3. Grinding machine according to claim 1 or 2, characterized in that the rod (122) is designed as a single-walled tube.

4. Grinding machine according to one of the preceding claims, characterized in that the rod (122) is formed from a fiber composite material, in particular a carbon fiber composite material.

5. Grinding machine according to claim 4, characterized in that the fibers of the fiber composite material in the rod (122) are electrically contacted, in particular at the proximal end (124) and / or distal end (126) of the rod (122), in order to establish an electrical connection, in particular an earthing, between the tool head (102) and the motor housing (128).

6. Grinding machine according to one of the preceding claims, characterized in that a discharge section (166) for discharging a flow (S) from the flow region (162) is provided at the proximal end (124) of the rod (122).

7. Grinding machine according to claim 6, characterized in that the discharge section (166) comprises a flow passage (170) formed in a wall of the rod (122) and a lateral flow discharge from the flow region (162) is preferably provided through the flow passage (170).

8. Grinding machine according to claim 6 or 7, characterized in that a connection device (168) for connecting a suction device is formed on the discharge section (166).

9. Grinding machine according to one of claims 7 or 8, characterized in that the discharge section (166) comprises at least one discharge element (172) which is arranged at the proximal end (124) of the rod (122) and through which a flow guide from the flow region (162) into the flow passage (170) is provided.

10. Grinding machine according to claim 9, characterized in that the flow guide from the flow area (162) into the flow passage (170) through a the interior (160) of the rod (122) facing discharge slope (174) of the at least one discharge element (172) is formed.

11. Grinding machine according to claim 9 or 10, characterized in that the at least one discharge element (172) is inserted into the proximal end (124) of the rod (122) or is plugged onto the proximal end (124) of the rod (122).

12. Grinding machine according to one of claims 9 to 11, characterized in that the discharge element (172) has antistatic properties.

13. Grinding machine according to one of claims 9 to 12, characterized in that the at least one discharge element (172) is attached to the motor housing (128) or is at least partially formed integrally with the motor housing (128).

14. Grinding machine according to one of claims 9 to 13, characterized in that the at least one discharge element (172) comprises a drive shaft passage (176) through which the drive shaft (134) is guided from the motor housing (128) into the interior (160) of the rod (122), wherein the drive shaft passage (176) preferably extends through the discharge slope (174).

15. Grinding machine according to one of the preceding claims, characterized in that the drive shaft (134) is provided at least in the interior (160) of the rod (122) with a casing (178), preferably made of rubber, a plastic or the like, and the casing (178) has a friction-minimizing guide (180), preferably made of a PTFE material or the like, for the drive shaft (134).

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