Hand-held grinder

Abstract

A grinder comprises a holding device for holding the grinder, a drive motor, a motor housing for the drive motor and a tool head, wherein the holding device comprises a substantially tubular rod which comprises a proximal end and a distal end, wherein the motor housing and the drive motor disposed therein are disposed on the proximal end, and wherein the tool head is disposed on the distal end, wherein the rod of the holding device is formed as a single-chamber rod in which are provided a drive shaft for driving the tool head and a flow region for a suction device.

Description

RELATED APPLICATION

[0001] This application is a continuation of international application No PCT / EP2024 / 075294 filed on Sept. 11, 2024 and claims the benefit of German application No. 10 2023 124 544.9 filed on Sep. 12, 2023, which are incorporated herein by reference in their entirety and for all purposes.FIELD OF INVENTION

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

[0003] Hand-held grinders are known, for example, from DE 10 2005 021 153 A1, WO 2008 / 033377 A2 or US 2006 / 0073778 A1.SUMMARY OF THE INVENTION

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

[0005] This object is achieved by a hand-held grinder as claimed in the independent claim(s). According to the invention, it is provided that the tubular rod of the holding device is formed as a single-chamber rod in which are provided a drive shaft for driving the tool head and a flow region for a suction device.

[0006] The tubular rod is provided in particular to interconnect the tool head and the motor housing.

[0007] By forming the tubular rod as a single-chamber rod, both the drive shaft for driving the tool head and the flow region for suctioning dust and abrasion arising during the operation of the grinder can be disposed conjointly within a chamber which is formed by the single-chamber rod.

[0008] In particular, a reduced weight of the tubular rod can be achieved by the single-chamber rod. In this way, easy and ideally fatigue-free grinding with the grinder can be made possible.

[0009] As a single-chamber rod, the tubular rod can moreover be produced cost-effectively.

[0010] The drive shaft is in particular a flexible shaft. Such a flexible shaft can be bent to deviate from a linear rotation axis by way of a specific bending radius. In a bent state, the flexible shaft can transmit a torque.

[0011] A refinement of the grinder can provide that the rod comprises an interior in which the flow region is formed and through which the drive shaft runs at least in portions.

[0012] In particular, the chamber formed by the single-chamber rod forms the interior of the tubular rod.

[0013] The interior of the tubular rod preferably extends within the entire length of extent of the tubular rod. This means that the interior of the tubular rod extends advantageously from the distal end of the tubular rod to the proximal end within the tubular rod.

[0014] At the distal end and / or at the proximal end of the tubular rod, the latter can have an end-side opening by which an access to the interior of the tubular rod is formed.

[0015] An advantageous refinement of the grinder can provide that the rod is formed as a single-wall tube.

[0016] Preferably, the tubular rod has a round, oval, elliptical or elongate O-shaped cross section. Likewise, the tubular rod can also have a triangular, quadrangular or polygonal cross section, preferably with radiused edges.

[0017] Preferably, a wall thickness of the tubular rod is designed to be less than an available internal cross section of the tubular rod.

[0018] It can be provided that a wall thickness of the tubular rod is a thickness of approximately 5 mm or less.

[0019] For example, a wall thickness of the tubular rod can be a thickness of approximately 3 mm or less.

[0020] For example, a wall thickness of the tubular rod can be a thickness of approximately 2 mm or less.

[0021] For example, the term "approximately" can mean a deviation of + / - 10%, preferably + / - 20%, from the specified value.

[0022] Additionally or alternatively, a wall thickness of the tubular rod can be a thickness of approximately 0.5 mm or more.

[0023] For example, a wall thickness of the tubular rod can be a thickness of approximately 0.75 mm or more.

[0024] For example, a wall thickness of the tubular rod can be a thickness of approximately 1 mm or more.

[0025] It can be provided that a wall thickness of the tubular rod is a thickness between approximately 0.5 mm and approximately 5 mm.

[0026] For example, a wall thickness of the tubular rod can be a thickness between approximately 0.75 mm and approximately 3 mm.

[0027] For example, a wall thickness of the tubular rod can be a thickness between approximately 1 mm and approximately 2 mm.

[0028] For example, a wall thickness of the tubular rod can be a thickness of 1.2 mm + / - 20% or 1.2 mm + / - 10% or 1.2 mm + / - 5%.

[0029] The internal 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.

[0030] It can be provided that the length of extent of the tubular rod is approximately 1000 mm or less.

[0031] For example, the length of extent of the tubular rod can be approximately 850 mm or less.

[0032] For example, the length of extent of the tubular rod can be approximately 700 mm or less.

[0033] Additionally or alternatively, it can be provided that the length of extent of the tubular rod is approximately 300 mm or more.

[0034] For example, the length of extent of the tubular rod can be approximately 450 mm or more.

[0035] For example, the length of extent of the tubular rod can be approximately 600 mm or more.

[0036] It can be provided that the length of extent of the tubular rod is between approximately 300 mm and approximately 1000 mm.

[0037] For example, the length of extent of the tubular rod can be between approximately 450 mm and approximately 850 mm.

[0038] For example, the length of extent of the tubular rod can be between approximately 600 mm and approximately 700 mm.

[0039] For example, the length of extent of the tubular rod can be 680 mm + / - 20% or 680 mm + / - 10% or 680 mm + / - 5%.

[0040] A design embodiment of the grinder can moreover provide that the rod is formed from a fiber composite material, in particular a carbon fiber composite material.

[0041] By forming the tubular rod from the fiber composite material, in particular from the carbon fiber composite material, it can be designed with a particularly low weight. As a result, a total weight of the grinder can be reduced, whereby significantly easier and significantly more fatigue-free grinding can be achieved by the grinder.

[0042] It can be provided that the weight of the tubular rod is approximately 250 g or less.

[0043] For example, the weight of the tubular rod can be approximately 200 g or less.

[0044] For example, the weight of the tubular rod can be approximately 175 g or less.

[0045] Additionally or alternatively, it can be provided that the weight of the tubular rod is approximately 75 g or more.

[0046] For example, the weight of the tubular rod can be approximately 100 g or more.

[0047] For example, the weight of the tubular rod can be approximately 125 g or more.

[0048] It can be provided that the weight of the tubular rod is between approximately 75 g and approximately 250 g.

[0049] For example, the weight of the tubular rod can be between approximately 100 g and approximately 200 g.

[0050] For example, the weight of the tubular rod can be between approximately 125 g and approximately 175 g.

[0051] For example, the weight of the tubular rod can be 152 g + / - 20% or 152 g + / - 10% or 152 g + / - 5%.

[0052] It can be provided that the total weight of the grinder can be approximately 3500 g or less.

[0053] For example, the total weight of the grinder can be approximately 3250 g or less.

[0054] For example, the total weight of the grinder can be approximately 3000 g or less.

[0055] Additionally or alternatively, it can be provided that the total weight of the grinder is approximately 2000 g or more.

[0056] For example, the total weight of the grinder can be approximately 2250 g or more.

[0057] For example, the total weight of the grinder can be approximately 2500 g or more.

[0058] It can be provided that the total weight of the grinder can be between approximately 2000 g and approximately 3500 g.

[0059] For example, the total weight of the grinder can be between approximately 2250 g and approximately 3250 g.

[0060] For example, the total weight of the grinder can be between approximately 2500 g and approximately 3000 g.

[0061] For example, the total weight of the grinder can be 2900 g + / - 20% or 2900 g + / - 10% or 2900 g + / - 5%.

[0062] It can be provided that a ratio of weight of the tubular rod to total weight of the grinder is approximately 0.1 or less.

[0063] For example, a ratio of weight of the tubular rod to total weight of the grinder can be approximately 0.08 or less.

[0064] For example, a ratio of weight of the tubular rod to total weight of the grinder can be approximately 0.06 or less.

[0065] Additionally or alternatively, it can be provided that a ratio of weight of the tubular rod to total weight of the grinder is approximately 0.02 or more.

[0066] For example, a ratio of weight of the tubular rod to total weight of the grinder can be approximately 0.03 or more.

[0067] For example, a ratio of weight of the tubular rod to total weight of the grinder can be approximately 0.04 or more.

[0068] It can be provided that a ratio of weight of the tubular rod to total weight of the grinder is between approximately 0.02 and approximately 0.1.

[0069] For example, a ratio of weight of the tubular rod to total weight of the grinder can be between approximately 0.03 and approximately 0.08.

[0070] For example, a ratio of weight of the tubular rod to total weight of the grinder can be between approximately 0.04 and approximately 0.06.

[0071] For example, the ratio of weight of the tubular rod to total weight of the grinder can be 0.05 + / - 20% or 0.05 + / - 10% or 0.05 + / - 5%.

[0072] In particular, by forming the tubular rod from the carbon fiber composite material, optimized haptics can also be achieved for a user of the grinder, since the carbon fiber composite material, in particular in comparison to a metallic material, provides a warm and non-slip surface when gripping the latter.

[0073] Advantageously, an internal wall of the tubular rod, which faces the interior of the tubular rod, can be provided with antistatic properties and / or be coated with an anti-adhesive coating. Thus, adhesion of the dust and abrasion resulting from the use of the grinder and extracted through the flow region of the tubular rod can be prevented or at least minimized.

[0074] Particularly preferably, it can be provided in the grinder that the fibers of the fiber composite material in the rod are electrically contacted in order to establish an electrical connection, in particular a grounding, between the tool head and the motor housing.

[0075] In particular, the fibers of the fiber composite material can be contacted at the proximal end and / or distal end of the rod to form the electrical connection, in particular the grounding, between the tool head and the motor housing.

[0076] In particular, since the carbon fibers of the carbon fiber composite material have electrically conducting properties, they can be subjected to a static charge of the rod during operation of the grinder due to the dust and abrasion flowing along the internal wall. Due to the electrical contact, in particular grounding, static charging of the rod can be prevented, so that dust and abrasion do not adhere to the internal wall of the rod.

[0077] In a refinement of the grinder, a discharge portion for discharging a flow from the flow region can be disposed on the proximal end of the rod.

[0078] The discharge portion is provided in particular to discharge the flow that flows from the tool head through the flow region of the tubular rod and includes the dust and abrasion created by the operation of the grinder from the flow region.

[0079] In particular, a flow routing of the flow from the tubular rod to an exterior is provided by the discharge portion.

[0080] A further advantageous design embodiment of the grinder can provide that the discharge portion comprises a flow passage formed in a wall of the rod, and a lateral flow discharge from the flow region is preferably provided through the flow passage.

[0081] A fluidic connection between the interior of the tubular rod and the exterior of the rod for discharging the flow from the flow region can be formed by the flow passage.

[0082] By forming the flow passage in the wall of the rod, the flow can be discharged laterally from the interior of the rod.

[0083] Thus, a deflection of the flow that flows in the flow region of the tubular rod toward the exterior can be provided by the flow passage.

[0084] In a refinement of the grinder, a connection device for connecting a suction device can be formed on the discharge portion.

[0085] The suction device is preferably a portable or stationary suction device, in particular a vacuum cleaner.

[0086] The suction device is able to be coupled to the connection device of the discharge portion, for example by means of a plug connection and / or snap-in connection.

[0087] Preferably, a coupling element of a hose or pipe of the suction device can be releasably connectable to the connection device of the discharge portion.

[0088] Advantageously, it can be provided in the grinder that the discharge portion comprises at least one discharge element, which is disposed on the proximal end of the rod and through which a flow routing from the flow region into the flow passage is provided.

[0089] The discharge element is preferably disposed on the proximal end of the rod so as to be at least partially in the interior of the rod.

[0090] The discharge element can be formed as a molded part and / or an injection-molded part or the like.

[0091] Preferably, the discharge element can be formed from a fiber composite material.

[0092] Particularly preferably, the discharge element can be formed from a carbon fiber composite material.

[0093] Alternatively, the discharge element can also be formed from a plastics material or a metallic material.

[0094] The deflection element is in particular designed to cause a flow deflection by which the substantially linear flow through the flow region in the tubular rod is deflected to be discharged laterally through the flow passage in the tubular rod.

[0095] A design embodiment of the grinder can moreover provide that the flow routing from the flow region into the flow passage is formed by a discharge ramp of the at least one discharge element, which faces the interior of the rod.

[0096] The discharge ramp facing the interior of the rod, i.e. the flow region in the rod, preferably has an orientation by which the flow through the flow region in the tubular rod is deflected in the direction of the flow passage provided laterally in the wall of the rod, so as to discharge the flow laterally from the interior of the rod.

[0097] Moreover, a refinement of the grinder can provide that the at least one discharge element is inserted into the proximal end of the rod or is attached to the proximal end of the rod.

[0098] For example, the discharge element can be inserted into the proximal end of the rod in the form of a plug.

[0099] The discharge ramp can form an inclined end face of the deflection element, which is aligned to the interior of the tubular rod by inserting or attaching the discharge element into or onto the proximal end of the rod.

[0100] In the grinder, the discharge element can advantageously have antistatic properties.

[0101] Preferably, the discharge element is formed from a material which has antistatic properties.

[0102] It can likewise be provided that at least the discharge ramp of the discharge element is provided with antistatic properties or is coated with an antistatic coating.

[0103] Advantageously, the discharge element, preferably the fibers of the fiber composite material, in particular the carbon fibers, can be electrically contacted.

[0104] By electrically contacting the fibers of the discharge element, an electrical connection, in particular a grounding, of the discharge element can be formed to prevent static charging of the discharge element due to the flow including the dust and abrasion along the latter.

[0105] Moreover, a design embodiment of the grinder can provide that the at least one discharge element is attached to the motor housing or is formed so as to be at least partially integral to the motor housing.

[0106] Consequently, the discharge element can be formed as a separate component which is attached to the motor housing and / or the proximal end of the tubular rod.

[0107] Likewise, the deflection element can be formed as a portion of the motor housing, or as a portion of part of the motor housing, so as to be at least partially integral.

[0108] In this context, the tubular rod can be attached to the discharge element or inserted into the latter when the tubular rod and the motor housing are coupled to one another.

[0109] In a refinement of the grinder, the at least one discharge element can comprise a drive shaft lead-through through which the drive shaft leads from the motor housing into the interior of the rod.

[0110] Preferably, it can be provided that the drive shaft lead-through extends through the discharge ramp.

[0111] The drive shaft lead-through can advantageously comprise a mounting for the drive shaft, for example in the form of a friction mounting or rolling mounting.

[0112] As a result, the drive shaft lead-through can form a radial mounting for the drive shaft.

[0113] The drive shaft lead-through can comprise or form a seal by which a fluidic seal is provided between the interior of the rod and the motor housing. This can prevent the flow of dust and abrasion from the flow region of the tubular rod from entering the motor housing.

[0114] In the grinder, the drive shaft can advantageously be provided at least in the interior of the rod with a casing, the latter preferably being made of rubber, a plastics material or the like, and the casing can have a friction-minimizing guide, preferably of a PTFE material or the like, for the drive shaft.

[0115] The casing can form a protection of the drive shaft from dust and abrasion in the interior or flow region of the rod and / or provide a guide or mounting of the drive shaft.

[0116] Preferably, the casing is formed from rubber or a plastics material. In particular, the casing has antistatic properties.

[0117] A friction-minimizing guide can be provided on an internal side of the casing that faces the drive shaft.

[0118] Especially in the bent state of the flexible shaft, low-friction rotation of the shaft can be enabled due to the friction-minimizing guide.

[0119] The friction-minimizing guide can be formed from a PTFE material or the like, for example.

[0120] It can be provided that the grinder, in particular a or the drive motor of the grinder, has a power consumption of approximately 1000 W or less.

[0121] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption of approximately 800 W or less.

[0122] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption of approximately 600 W or less.

[0123] Additionally or alternatively, it can be provided that the grinder, in particular a or the drive motor of the grinder, has a power consumption of approximately 200 W or more.

[0124] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption of approximately 300 W or more.

[0125] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption of approximately 400 W or more.

[0126] It can be provided that the grinder, in particular a or the drive motor of the grinder, has a power consumption between approximately 200 W and approximately 1000 W.

[0127] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption between approximately 300 W and approximately 800 W.

[0128] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption between approximately 400 W and approximately 600 W.

[0129] For example, the grinder, in particular a or the drive motor of the grinder, can have a power consumption of 500 W + / - 20% or 500 W + / - 10% or 500 W + / - 5%.

[0130] It can be provided that a ratio of total weight of the grinder to power consumption of the grinder is approximately 17.5 kg / kW or less.

[0131] For example, a ratio of total weight of the grinder to power consumption of the grinder can be approximately 12.5 kg / kW or less.

[0132] For example, a ratio of total weight of the grinder to power consumption of the grinder can be approximately 7.5 kg / kW or less.

[0133] Additionally or alternatively, it can be provided that a ratio of total weight of the grinder to power consumption of the grinder is approximately 2 kg / kW or more.

[0134] For example, a ratio of total weight of the grinder to power consumption of the grinder can be approximately 3 kg / kW or more.

[0135] For example, a ratio of total weight of the grinder to power consumption of the grinder can be approximately 4 kg / kW or more.

[0136] It can be provided that a ratio of total weight of the grinder to power consumption of the grinder is between approximately 2 kg / kW and approximately 17.5 kg / kW.

[0137] For example, a ratio of total weight of the grinder to power consumption of the grinder can be between approximately 3 kg / kW and approximately 12.5 kg / kW.

[0138] For example, a ratio of total weight of the grinder to power consumption of the grinder can be between approximately 4 kg / kW and approximately 7.5 kg / kW.

[0139] For example, the ratio of total weight of the grinder to power consumption of the grinder can be 5.8 kg / kW + / - 20% or 5.8 kg / kW + / - 10% or 5.8 kg / kW + / - 5%.

[0140] Further preferred features and / or advantages of the invention are the subject matter of the description hereunder and of the graphic illustration of exemplary embodiments.BRIEF DESCRIPTION OF THE DRAWINGS

[0141] FIG. 1 shows a schematic perspective illustration of a hand-held grinder, viewed toward an upper side of the grinder;

[0142] FIG. 2 shows a schematic sectional view of a tool head of the grinder;

[0143] FIG. 3 shows a schematic sectional view of a connecting portion between a holding device and a flexible tubular element of the grinder;

[0144] FIG. 4 shows a schematic sectional view of a motor housing of the grinder;

[0145] FIG. 5 shows a schematic perspective sectional view of the motor housing of the grinder in FIG. 4;

[0146] FIG. 6 shows a further schematic perspective sectional view of the motor housing of the grinder in FIG. 4;

[0147] FIG. 7 shows a schematic perspective detailed section view of a connecting portion between the holding device and the motor housing;

[0148] FIG. 8 shows a schematic sectional view of a housing entrance for a current cable of the grinder;

[0149] FIG. 9 shows a schematic perspective view of the housing entrance according to FIG. 8 with the current cable in a prefixed arrangement;

[0150] FIG. 10 shows a schematic perspective view of the housing entrance with the current cable in a fixed arrangement.

[0151] Identical or functionally equivalent elements are provided with the same reference signs in all of the figures.DETAILED DESCRIPTION OF THE DRAWINGS

[0152] FIGS. 1 -10 show an embodiment of a hand-held grinder which as an entity is denoted by the reference sign 100 and is also referred to as a long-neck grinder. With such a grinder 100, large areas, especially wall surfaces, ceiling surfaces and floor surfaces, are able to be easily and conveniently machined.

[0153] The grinder 100 has a tool head 102 which comprises a tool holder 104 for receiving a machining tool 106, for example an abrasive.

[0154] The tool head 102 is mounted on a holding device 110 of the grinder 100 so as to be pivotable by means of a pivoting apparatus 108.

[0155] The pivoting apparatus 108 comprises a fork element 112 and a pivot element 116 which is disposed so as to be pivotable about a pivot axis 114 on the fork element 112.

[0156] The pivot element 116 is designed, for example, as a pivot ring 118, as can be seen in particular in FIG. 2.

[0157] By means of the pivot ring 118, the fork element 112 is pivotably connected to a housing 120 of the tool head 102.

[0158] 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 is pivotable relative to the fork element 112 about two pivot axes 114 that are aligned so as to be substantially perpendicular to one another.

[0159] The holding device 110 of the grinder 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.

[0160] The fork element 112 and the tool head 102 disposed thereon are provided on the distal end 126 of the tubular rod 122 of the holding device 110.

[0161] A motor housing 128 of the grinder 100 is disposed on the proximal end 124 of the tubular rod 122 of the holding device 110.

[0162] A drive motor 130 of the grinder 100 is received in the motor housing 128 of the grinder 100.

[0163] A grip element 132 is provided on the motor housing 128, by which a user can grip the grinder 100.

[0164] 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 disposed thereon is in particular able to be driven in a rotating, oscillating and / or eccentric manner.

[0165] The flexible shaft 134 extends at least in portions within the tubular rod 122.

[0166] Moreover, the flexible shaft 134 extends at least in portions in a flexible tubular element 136, by means of which the tubular rod 122 is coupled to the housing 102.

[0167] For an optimized weight distribution of the grinder 100, the drive motor 130 is preferably disposed on a side opposite the tool head 102 of a central axis 138 of the tubular rod 122.

[0168] In the use state of the grinder 100, the user can engage on the grip element 132 and the tubular rod 122 of the holding device 110 of the grinder 100, for example, to carry out a machining procedure.

[0169] In order to achieve an action radius within which the user, proceeding from a predefined 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 disposed on the motor housing 128 or the grip element 132.

[0170] The extension element 140 can be releasably fastened to the grinder 100, in particular to the motor housing 128 or to the grip element 132 of the grinder 100.

[0171] 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 grinder 100.

[0172] Illustrated in a longitudinal sectional view in FIG. 3 is a schematic detailed view of a connecting portion 144 between the holding device 110 and the flexible tubular element 136 of the grinder 100.

[0173] The connecting portion 144 comprises a sleeve element 146 on which two mutually opposite insertion portions 148 are formed.

[0174] An end of the flexible tubular element 136 that lies opposite the tool head 102 is inserted on the one side, and the distal end 126 of the tubular rod 122 is inserted on the opposite side, into the insertion portions 148 of the sleeve element 146, in order for these to be coupled to one another.

[0175] Fastening devices 152, which are in each case assigned to the insertion portions 148 of the sleeve element 146, can be provided on the sleeve element 146.

[0176] The fastening devices 152 can comprise fastening means, for example screws, pins, snap-fit elements or the like, in order to couple, preferably releasably couple, the tubular rod 122 and the flexible tubular element 136 to the sleeve element 146.

[0177] 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 in order to guide the latter from the tubular rod 122 into the flexible tubular element 136.

[0178] The guide device 150 forms a mounting for the flexible shaft 134. The guide device 150 can comprise, for example, a friction bearing or a rolling bearing, by which the flexible shaft 134 is mounted so as to be rotatable in a radial direction.

[0179] The sleeve element 146 has a cavity 154 in the interior, by which a fluidic connection between an interior 160 of the tubular rod 122 and an interior of the flexible tubular element 136 is formed, for which further details will be provided hereunder.

[0180] The flexible shaft 134 extends in particular within this cavity 154 of the sleeve element 146.

[0181] FIG. 4 shows a schematic sectional view of the motor housing 128 of the grinder 100, and FIGS. 5 and 6 show in each case further schematic perspective sectional views of the motor housing 128 shown in FIG. 4 from different viewing directions.

[0182] Provided on the motor housing 128 is a connecting portion 156 for coupling the proximal end 124 of the tubular rod 122 to the motor housing 128.

[0183] The tubular rod 122 is inserted by way of the proximal end 124 into the connecting portion 156 on the motor housing 128.

[0184] A fastening device 158 for fastening the tubular rod 122 to the motor housing 128 can be provided on the connecting portion 156.

[0185] The fastening device 158 can comprise a plurality of fastening means, for example screws, pins, snap-fit elements or the like, in order to fasten, preferably releasably fasten, the tubular rod 122 to the motor housing 128.

[0186] The tubular rod 122 is designed in particular as a single-chamber rod.

[0187] Single-chamber rod is to be understood to mean that formed in the tubular rod 122 is an interior 160, preferably one a single interior 160, which extends from the proximal end 124 of the tubular rod 122 to the distal end 126 of the tubular rod 122.

[0188] Provided at the proximal end 124 of the tubular rod 122 and at the distal end 126 of the tubular rod 122 are openings through which the interior 160 is accessible from both ends 124, 126.

[0189] Preferably, the tubular rod 122 formed as a single-chamber rod is a single-walled tube.

[0190] The tubular rod 122 can, for example, have a round, oval, elliptical or elongate O-shaped cross section.

[0191] Likewise, the tubular rod 122 can have a triangular, quadrangular or polygonal cross section, preferably with radiused edges.

[0192] In particular, the tubular rod 122 is formed from a fiber composite material, preferably a carbon fiber composite material.

[0193] In order to minimize adhesion properties of the tubular rod 122, at least the interior 160 of the tubular rod 122 can be provided with antistatic properties or be coated with an antistatic and / or non-adhesive coating.

[0194] In particular, the fibers of the fiber composite material are electrically contacted at the proximal and distal end 124, 126 of the rod 122 so that an electrical connection, in particular a grounding, between the tool head 102 and the motor housing 128 is formed.

[0195] In particular, carbon fibers of the carbon fiber composite material have electrically conducting properties, so that the rod can be statically charged due to the dust and abrasion flowing along the internal wall. This can be prevented by the electrical contact, in particular grounding, so as to prevent dust and abrasion from adhering in the flow region 162 within the rod 122.

[0196] The grinder 100 comprises a suction channel 164 which extends from the tool head 102 to the proximal end 124 of the tubular rod 122.

[0197] Dust and abrasion created in the region of the tool head 102 during the operation of the grinder 100 can be discharged through the suction channel 164 and be disposed of by way of the suction channel 164.

[0198] The flexible tubular element 136 and the tubular rod 122 form fluidic portions of the suction channel 164.

[0199] In particular, the flow region 162, which forms a fluidic portion of the suction channel 164, is formed by the interior 160 of the tubular rod 122.

[0200] Provided at the proximal end 124 of the tubular rod 122 is a discharge portion 166 through which a flow S, i.e. the suctioned dust and abrasion, flowing through the flow region 162 can be discharged or suctioned.

[0201] Formed on the discharge portion 166 is a connection device 168 by way of which a suction device, in particular a vacuum cleaner, not illustrated in more detail, is able to be coupled to the discharge portion 166. This means that the dust and abrasion created during operation can be extracted and disposed of through the suction channel 164.

[0202] The discharge portion 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.

[0203] Advantageously, the discharge portion 166 is disposed on a side of the central axis 138 of the tubular rod 122 that lies 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.

[0204] The discharge portion 166 comprises a flow passage 170, which is formed in the wall of the tubular rod 122.

[0205] The flow passage 170 is formed as a hole or recess in the wall of the tubular rod 122.

[0206] Advantageously, the flow passage 170 can be formed in such a way that the recess extends slit-like from the proximal end 124 of the tubular rod 122 in the direction of the distal end 126 of the tubular rod 122.

[0207] Preferably, the flow passage 170 is disposed on a side of the central axis 138 of the tubular rod 122 that lies opposite the drive motor 130, or is disposed on the same side as the tool head 102 in terms of the central axis 138 of the tubular rod 122.

[0208] The discharge portion 166 comprises a discharge element 172 which is inserted into the interior 160 of the tubular rod 122 at the proximal end 124 of the tubular rod 122.

[0209] This discharge element 172 can be attached to the motor housing 128 or be formed integrally with the motor housing 128.

[0210] The discharge element 172 can be formed as a molded part and / or an injection-molded part or the like.

[0211] Preferably, the discharge element 172 is formed from a fiber composite material, in particular a carbon fiber composite material. Likewise, the discharge element 172 can be formed from a plastics material or metal.

[0212] Advantageously, the discharge element 172, in particular the fibers of the fiber composite material, is electrically contacted to form an electrical connection, in particular a grounding, to the discharge element 172. This prevents static charging of the discharge element 172 due to the dust and abrasion flowing along it.

[0213] The discharge element 172 is designed in such a way that it is inserted into the proximal end 124 of the rod 122. For example, the discharge element 172 can be inserted at the proximal end 124 of the rod 122 in the manner of a plug into the interior 160 of the rod 122.

[0214] Alternatively, the discharge element 172 can also be attached to or onto the proximal end 124 of the rod 122.

[0215] Preferably, the interior 160 of the rod 122, i.e. the flow region 162 in the interior 160 of the rod 122, is closed off in a fluid-tight manner toward the proximal end 124 of the tubular rod 122 by the discharge element 172. The flow S flowing in the flow region 162 of the rod 122 is prevented from flowing into the interior of the motor housing 128.

[0216] Formed by the discharge element 172 in the flow region 162 of the rod 122 is a flow routing by which the flow S flowing in the flow region 162 is directed from the flow region 162 into the flow passage 170.

[0217] For this purpose, a discharge ramp 174 is formed on the discharge element 172, which is aligned in such a way that it faces the flow region 162 of the rod 122.

[0218] Due to this discharge ramp 174, the flow S impacting the discharge element 172, in particular the dust and abrasion created and suctioned in the region of the tool head 102 in the operation of the grinder 100, is directed from the flow region 162 into the flow passage 170 so as to be discharged from the flow region 162 of the rod 122 by way of the discharge portion 166.

[0219] The discharge ramp 174 extends from a wall portion of the tubular rod 122 opposite the flow passage 170 at an inclined angle to a rear portion of the flow passage 170 when viewed in the flow direction.

[0220] The discharge ramp 174 thus extends from the wall portion of the tubular rod 122, which is opposite the flow passage 170, at the inclined angle through the interior 160 of the tubular rod 122 to the rear portion of the flow passage 170.

[0221] Advantageously, the discharge ramp 174 transitions to the flow passage 170 so as to be substantially flush with the latter.

[0222] The lateral flow discharge from the flow region 162 into the discharge portion 166 is formed in this way.

[0223] Moreover, formed on the discharge element 172 is a drive shaft lead-through 176 through which the flexible shaft 134 leads from the interior 160 of the tubular rod 122 into the motor housing 128.

[0224] The drive shaft lead-through 176 extends in particular through the discharge ramp 174 of the discharge element 172.

[0225] The drive shaft lead-through 176 can have a mounting, for example a friction mounting or rolling mounting, by which the flexible shaft 134 is radially mounted.

[0226] In particular, the drive shaft lead-through 176 forms a seal, or comprises a sealing element to form a fluid-tight connection between the interior 160 of the rod 122 and the motor housing 128.

[0227] In the grinder 100 it is provided in particular that the flexible shaft 134 extends through the flow region 162 of the tubular rod 122.

[0228] This means that provided in the same interior 160 of the rod 122 in the tubular rod 122 formed as a single-chamber rod are the flow region 162 for suctioning the dust and abrasion as well as the flexible shaft 134 for driving the tool head 102.

[0229] For protecting and / or guiding the drive shaft 134, the latter has a casing 178 in the interior 160 of the rod 122. This casing 178 is preferably formed from rubber or a plastics material.

[0230] The casing 178 can extend into the drive shaft lead-through 176 at the proximal end 124 of the rod 122 and rest on a circumferential surface 182 of the drive shaft lead-through 176. Thus, for example, the seal between the flow region 162 of the rod 122 and the motor housing 128 can be formed.

[0231] The casing 178 has in the interior a friction-minimizing guide 180 by 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.

[0232] Illustrated in FIG. 8 is a schematic sectional view of a housing entrance 184 of the motor housing 128 of the grinder 100. This housing entrance 184 is provided for passing a current cable 186 into the motor housing 128, in particular to supply the drive motor 130 of the grinder 100 with current.

[0233] The housing entrance 184 comprises a housing entrance portion 188 which is formed integrally with the motor housing 128 and through which the current cable 186 is routed.

[0234] Preferably, the housing entrance 184 has a circular passage cross section.

[0235] One or a plurality of engagement portions 192 is / are formed on an internal wall portion 190 of the housing entrance portion 188. The engagement portion 192 is specified in such a way that a protrusion 194 on a bush 196, in particular a rubber bush, which surrounds the current cable 186 at least in the region of the housing entrance 184, engages in the former in order to fix the bush 196 on the motor housing 128.

[0236] The bush 196 is preferably provided to provide a seal toward the interior of the motor housing 128 and / or a kink protection for the current cable 186 leading through the housing entrance 184.

[0237] The housing entrance 184 comprises a cable fixation 198, which is provided in the interior of the motor housing 128, so as to correspond to the housing entrance portion 188.

[0238] The cable fixation 198 comprises a clamping device 200 and a fixing device 202.

[0239] Preferably, the clamping device 200 and the fixing device 202 are disposed substantially behind one another in an introduction direction of the current cable 186 through the housing entrance 184.

[0240] When assembling the motor housing 128, the current cable 186 is first passed through the housing entrance 184 of the motor housing 128 and placed into the clamping device 200 and the fixing device 202, as shown in FIG. 9.

[0241] The clamping device 200 is formed in such a way that it comprises two clamping elements 204 which are disposed at a mutual spacing. Preferably, the clamping elements 204 are disposed parallel to one another or disposed at a slightly inclined angle to one another.

[0242] In particular, the clamping elements 204 are disposed at a mutual spacing which is designed to be slightly smaller than a diameter of the current cable 186, so that the current cable 186 is able to be clamped between the clamping elements 202.

[0243] The mutually spaced apart clamping elements 204 are preferably formed integrally with the motor housing 128, in particular with one housing shell or two or a plurality of housing shells of the motor housing 128, for example a lower or a right-hand housing shell of the motor housing 128.

[0244] For assembling the motor housing 128, the current cable 186 can be prefixed in this way, i.e. it is first passed through the housing entrance portion 188 and subsequently clamped in a defined position between the clamping elements 202 of the clamping device 200.

[0245] The fixing device 202 comprises several fixing elements 206 which are each provided mutually corresponding pairs.

[0246] In the embodiment illustrated in FIG. 8, for example, three pairs of fixing elements 206 are disposed behind one another in the introduction direction of the current 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.

[0247] The fixing elements 206 are preferably formed integrally with the motor housing 128.

[0248] 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-hand 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-hand housing shell of the motor housing 128.

[0249] The pairs of mutually corresponding fixing elements 206 are formed in such a way that in an assembled configuration of the motor housing 128, a fixing region for the current cable 186 is formed between the fixing elements 206.

[0250] For this purpose, each pair of fixing elements 206 is designed in such a way that mutually opposite recesses 208 are formed on the fixing elements 206.

[0251] The recesses 208 on the fixing elements 206 can be V-shaped, semicircular or the like.

[0252] The fixing region for fixing the current cable 186 between the fixing elements 206 is formed by the mutually opposite recesses 208 of the respective pair of fixing elements 206.

[0253] In particular, it is provided by the V-shaped, semicircular or the similarly shaped recesses 208 of the respective pair of fixing elements 206 that a passage cross section of the fixing region formed between the fixing elements 206 is successively reduced by the assembly of the motor housing 128 and in the final assembled configuration of the motor housing 128 has a slightly smaller passage cross section than the cross section of the current cable 186.

[0254] In this way, in the assembled configuration of the motor housing 128, i.e. for the use of the grinder 100, the current cable 186 is fixed in a stationary position by a press-fit between the fixing elements 206.

[0255] The cable fixation 198 formed in this manner is consequently provided to first prefix the current cable 186 in a defined position by the clamping device 200 for assembling the motor housing 128, so as to subsequently be able to assemble the housing shells of the motor housing 128 easily due to the prefixed and thus positioned current cable 186 and to fix the current cable 186 in a stationary position by the fixing device 202.LIST OF REFERENCE SIGNS100 Grinder

[0257] 102 Tool head

[0258] 104 Tool holder

[0259] 106 Machining tool

[0260] 108 Pivoting apparatus

[0261] 110 Holding device

[0262] 112 Fork element

[0263] 114 Pivot axis

[0264] 116 Pivot element

[0265] 118 Pivot ring

[0266] 120 Housing

[0267] 122 Tubular rod

[0268] 124 Proximal end

[0269] 126 Distal end

[0270] 128 Motor housing

[0271] 130 Drive motor

[0272] 132 Grip element

[0273] 134 Flexible shaft

[0274] 136 Flexible tubular element

[0275] 138 Central axis

[0276] 140 Extension element

[0277] 142 Tubular rod

[0278] 144 Connecting portion

[0279] 146 Sleeve element

[0280] 148 Insertion portion

[0281] 150 Guide device

[0282] 152 Fastening device

[0283] 154 Cavity

[0284] 156 Connecting portion

[0285] 158 Fastening device

[0286] 160 Interior

[0287] 62 Flow region

[0288] 164 Suction channel

[0289] 166 Discharge portion

[0290] 168 Connection device

[0291] 170 Flow passage

[0292] 172 Discharge element

[0293] 174 Discharge ramp

[0294] 176 Drive shaft lead-through

[0295] 178 Casing

[0296] 180 Friction-minimizing guide

[0297] 182 Circumferential surface

[0298] 184 Housing entrance

[0299] 186 Current cable

[0300] 188 Housing entrance portion

[0301] 190 Internal wall portion

[0302] 192 Engagement portion

[0303] 194 Protrusion

[0304] 196 Bush

[0305] 198 Cable fixation

[0306] 200 Clamping device

[0307] 202 Fixing device

[0308] 204 Clamping element

[0309] 206 Fixing element

[0310] 208 Recess

[0311] S Flow direction

Claims

1. A hand-held grinder comprising:a holding device for holding the grinder;a drive motor;a motor housing for the drive motor; anda tool head, whereinthe holding device includes a substantially tubular rod which includes a proximal end and a distal end,the motor housing and the drive motor disposed therein are disposed on the proximal end,the tool head is disposed on the distal end, andthe rod of the holding device is formed as a single-chamber rod in which are provided a drive shaft for driving the tool head and a flow region for a suction device.

2. The grinder according to claim 1, whereinthe rod includes an interior in which the flow region is formed and through which the drive shaft runs at least in portions.

3. The grinder according to claim 1, whereinthe rod is formed as a single-wall tube.

4. The grinder according to claim 1, whereinthe rod is formed from a fiber composite material or a carbon fiber composite material.

5. The grinder according to claim 4, whereinthe fibers of the fiber composite material in the rod are electrically contacted, or are electrically contacted at the proximal end and / or distal end of the rod, in order to establish an electrical connection, or a grounding, between the tool head and the motor housing.

6. The grinder according to claim 1, whereinprovided at the proximal end of the rod is a discharge portion for discharging a flow from the flow region.

7. The grinder according to claim 6, whereinthe discharge portion includes a flow passage formed in a wall of the rod; orthe discharge portion includes a flow passage formed in a wall of the rod and a lateral flow discharge from the flow region is provided through the flow passage.

8. The grinder according to claim 6, whereinformed on the discharge portion is a connection device for connecting a suction device.

9. The grinder according to claim 7, whereinthe discharge portion includes at least one discharge element which is disposed on the proximal end of the rod and through which a flow routing from the flow region into the flow passage is provided.

10. The grinder according to claim 9, whereinthe flow routing from the flow region into the flow passage is formed by a discharge ramp of the at least one discharge element, which faces the interior of the rod.

11. The grinder according to claim 9, whereinthe at least one discharge element is inserted into the proximal end of the rod or is attached to the proximal end of the rod.

12. The grinder according to claim 9, whereinthe discharge element has antistatic properties.

13. The grinder according to claim 9, whereinthe at least one discharge element is attached to the motor housing, or is formed so as to be at least partially integral to the motor housing.

14. The grinder according to claim 9, whereinthe at least one discharge element includes a drive shaft lead-through through which the drive shaft leads from the motor housing into the interior of the rod; orthe at least one discharge element includes a drive shaft lead-through through which the drive shaft leads from the motor housing into the interior of the rod andthe drive shaft lead-through extends through the discharge ramp.

15. The grinder according to claim 1, whereinthe drive shaft is provided at least in the interior of the rod with a casing, or with a casing being of rubber or a plastics material, and the casing has a friction-minimizing guide, or a friction-minimizing guide of a PTFE material, for the drive shaft.

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