CA3141980A1 - Abrasive cutter and method for cutting through a rail of a track - Google Patents
Abrasive cutter and method for cutting through a rail of a track Download PDFInfo
- Publication number
- CA3141980A1 CA3141980A1 CA3141980A CA3141980A CA3141980A1 CA 3141980 A1 CA3141980 A1 CA 3141980A1 CA 3141980 A CA3141980 A CA 3141980A CA 3141980 A CA3141980 A CA 3141980A CA 3141980 A1 CA3141980 A1 CA 3141980A1
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- CA
- Canada
- Prior art keywords
- drive
- cutting disc
- abrasive cutter
- cutting
- drive motor
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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- 238000005520 cutting process Methods 0.000 title claims abstract description 167
- 238000000034 method Methods 0.000 title claims description 8
- 238000001816 cooling Methods 0.000 claims description 19
- 238000012423 maintenance Methods 0.000 abstract description 9
- 230000008901 benefit Effects 0.000 description 7
- 230000033001 locomotion Effects 0.000 description 7
- 230000005540 biological transmission Effects 0.000 description 6
- 230000005484 gravity Effects 0.000 description 4
- 238000013021 overheating Methods 0.000 description 4
- 238000013519 translation Methods 0.000 description 4
- 210000003746 feather Anatomy 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000012544 monitoring process Methods 0.000 description 3
- 239000002826 coolant Substances 0.000 description 2
- 239000012809 cooling fluid Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000013016 damping Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B27/00—Other grinding machines or devices
- B24B27/06—Grinders for cutting-off
- B24B27/08—Grinders for cutting-off being portable
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B41/00—Component parts such as frames, beds, carriages, headstocks
- B24B41/007—Weight compensation; Temperature compensation; Vibration damping
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01B—PERMANENT WAY; PERMANENT-WAY TOOLS; MACHINES FOR MAKING RAILWAYS OF ALL KINDS
- E01B31/00—Working rails, sleepers, baseplates, or the like, in or on the line; Machines, tools, or auxiliary devices specially designed therefor
- E01B31/02—Working rail or other metal track components on the spot
- E01B31/04—Sectioning or slitting, e.g. by sawing, shearing, flame-cutting
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Processing Of Stones Or Stones Resemblance Materials (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Machines For Laying And Maintaining Railways (AREA)
- Sawing (AREA)
Abstract
An abrasive cutter for cutting a rail of a track comprises a drive for driving a cutting disc holder in rotation. A cutting disc is attached to the cutting disc holder by means of at least one clamping element. The drive is directly coupled to the cutting disc holder and has a maximum transverse extent which is at most equal to a diameter of at least one clamping element. The drive comprises an electric drive motor with a power density Pspez = 0.5 kW/kg. The abrasive cutter allows a reliable, efficient, user-friendly and low-maintenance through-cutting of a rail of a track.
Description
Angle Grinder and Method for Cutting Through a Rail of a Track The present application claims priority of German utility model application DE 20 2019 103 132.8, the content of which is included herein by reference.
The invention concerns an abrasive cutter and method for cutting through a rail of a track.
Abrasive cutters with direct drive for cutting through a rail of a track are known from the prior art. Such abrasive cutters have a hydraulic drive which is actively connected to the shaft of the cutting disc. The production and maintenance of known abrasive cutters are complex.
EP 3 216 567 Al discloses a disc cutter in which the cutting disc is driven in rotation by an electric drive motor. The electric drive motor is coupled directly to a cutting disc holder by means of a drive shaft. The rotational axis of the cutting disc or cutting disc holder runs either coaxially to the drive axis of the drive motor or is offset in parallel to the drive axis.
It is an object of the present invention to create a simple abrasive cutter which allows through-cutting of the rail of a track in a reliable, efficient, user-friendly and low-maintenance fashion.
This object is achieved by an abrasive cutter with the features of claim 1.
The abrasive cutter according to the invention comprises an electric drive motor as the drive. The electric drive motor has a drive shaft and a drive axis, wherein the drive shaft is directly coupled to the cutting disc holder.
Because the drive axis and the rotational axis of the cutting disc holder are Date Recue/Date Received 2021-11-24
The invention concerns an abrasive cutter and method for cutting through a rail of a track.
Abrasive cutters with direct drive for cutting through a rail of a track are known from the prior art. Such abrasive cutters have a hydraulic drive which is actively connected to the shaft of the cutting disc. The production and maintenance of known abrasive cutters are complex.
EP 3 216 567 Al discloses a disc cutter in which the cutting disc is driven in rotation by an electric drive motor. The electric drive motor is coupled directly to a cutting disc holder by means of a drive shaft. The rotational axis of the cutting disc or cutting disc holder runs either coaxially to the drive axis of the drive motor or is offset in parallel to the drive axis.
It is an object of the present invention to create a simple abrasive cutter which allows through-cutting of the rail of a track in a reliable, efficient, user-friendly and low-maintenance fashion.
This object is achieved by an abrasive cutter with the features of claim 1.
The abrasive cutter according to the invention comprises an electric drive motor as the drive. The electric drive motor has a drive shaft and a drive axis, wherein the drive shaft is directly coupled to the cutting disc holder.
Because the drive axis and the rotational axis of the cutting disc holder are Date Recue/Date Received 2021-11-24
- 2 -aligned, a simple force transmission is achieved between the drive shaft and the cutting disc holder. Aligned or congruent means that the rotational axis is coaxial or identical to the drive axis. In particular, the electric drive motor is a brush less electric motor.
Because of the use of an electric drive motor, in comparison with a.
hydraulic drive, no additional elements, such as for example hydraulic lines, nozzles or valves, need be fitted in the abrasive cutter. The omission of these additional elements at the same time eliminates the problem of leakage and gap losses caused for example by a change in viscosity following temperature changes.
The reduction of additional elements has the further advantage that the abrasive cutter has lower energy losses and hence a higher efficiency. in particular, the efficiency of the abrasive cutter is over 90%, in particular over 95%, advantageously over 99%. Thus the abrasive cutter also has a lower energy consumption owing to the electric drive motor. At the same time, because of the omission of additional elements, the abrasive cutter comprises fewer components, in particular fewer wearing parts, whereby the maintenance complexity and maintenance cost may be significantly lowered and the time between individual service intervals can be extended.
At the same time, the abrasive cutter has a lower overall weight.
In addition, the use of an electric drive motor eliminates the problem affecting known abrasive cutters, that these are often subject to pressure and movement fluctuations, whereby switching impacts and uneven movements occur. This avoids a tilting of the cutting disc and at the same time guarantees that the rail can be cut through in a reliable and efficient fashion.
Date Recue/Date Received 2021-11-24
Because of the use of an electric drive motor, in comparison with a.
hydraulic drive, no additional elements, such as for example hydraulic lines, nozzles or valves, need be fitted in the abrasive cutter. The omission of these additional elements at the same time eliminates the problem of leakage and gap losses caused for example by a change in viscosity following temperature changes.
The reduction of additional elements has the further advantage that the abrasive cutter has lower energy losses and hence a higher efficiency. in particular, the efficiency of the abrasive cutter is over 90%, in particular over 95%, advantageously over 99%. Thus the abrasive cutter also has a lower energy consumption owing to the electric drive motor. At the same time, because of the omission of additional elements, the abrasive cutter comprises fewer components, in particular fewer wearing parts, whereby the maintenance complexity and maintenance cost may be significantly lowered and the time between individual service intervals can be extended.
At the same time, the abrasive cutter has a lower overall weight.
In addition, the use of an electric drive motor eliminates the problem affecting known abrasive cutters, that these are often subject to pressure and movement fluctuations, whereby switching impacts and uneven movements occur. This avoids a tilting of the cutting disc and at the same time guarantees that the rail can be cut through in a reliable and efficient fashion.
Date Recue/Date Received 2021-11-24
- 3 -The drive axis runs coaxially to the rotational axis. Because the maximum transverse extent of the drive is at most equal to the diameter of the at least one clamping clement for fixing the cutting disc to thc cutting disc holder, it is avoided that the drive or its housing protrudes into the cutting region of the cutting disc and reduces the cutting region. This therefore guarantees that the cutting disc, the diameter of which reduces successively due to wear during through-cutting of the rail, is utilized to the optimum. In other words, there is no restriction in cutting depth. The maximum transverse extent of the drive is in particular reduced by the high power density Pspõ, of the electric drive motor.
Preferably, the abrasive cutter is configured for use of cutting discs with a maximum nominal diameter DN. For the maximum transverse extent E, in particular E 0.6 DN, in particular E 0.5 = DN, and in particular E 0.4 = DN. Preferably, E > 0.2 DN. The maximum transverse extent is defined in particular perpendicularly to the drive axis or rotational axis and/or in the direction of the plane of symmetry of a cutting region of a cutting disc.
Preferably, the drive comprises the electric drive motor and a housing in which the electric drive motor is arranged and in particular mounted. The electric drive motor comprises a stator and a rotor. The drive shaft is connected to the rotor or is part of the rotor. Preferably, the stator delimits an interior in which the rotor is arranged. The rotor thus forms an internal rotor. The rotor preferably comprises permanent magnets. The permanent magnets are in particular attached to the drive shaft. The stator preferably comprises electromagnets.
Date Recue/Date Received 2021-11-24
Preferably, the abrasive cutter is configured for use of cutting discs with a maximum nominal diameter DN. For the maximum transverse extent E, in particular E 0.6 DN, in particular E 0.5 = DN, and in particular E 0.4 = DN. Preferably, E > 0.2 DN. The maximum transverse extent is defined in particular perpendicularly to the drive axis or rotational axis and/or in the direction of the plane of symmetry of a cutting region of a cutting disc.
Preferably, the drive comprises the electric drive motor and a housing in which the electric drive motor is arranged and in particular mounted. The electric drive motor comprises a stator and a rotor. The drive shaft is connected to the rotor or is part of the rotor. Preferably, the stator delimits an interior in which the rotor is arranged. The rotor thus forms an internal rotor. The rotor preferably comprises permanent magnets. The permanent magnets are in particular attached to the drive shaft. The stator preferably comprises electromagnets.
Date Recue/Date Received 2021-11-24
- 4 -The electric drive motor has a high power density or high specific power Psp,. The power density is the ratio of the nominal power P of the electric drive motor to its mass M. For the power density of the electric drive motor, Pspez 0.5 kW/kg, advantageously Ps p, 0.8 kW/kg, and advantageously Psp, > 1.0 kW/kg. Preferably, the electric drive motor has a nominal power P, wherein P > 2 kW, in particular P? 3 kW, and in particular P? 5 kW. For the nominal power P., preferably P < 10 kW, in particular P < 8 kW, in particular P < 6 kW, and in particular P < 4 kW.
Because of the comparatively low weight, the abrasive cutter is user-friendly and easy to guide. The drive or electric drive motor, because of its compactness, guarantees that the cutting depth is not reduced.
Because of the direct coupling of the drive, the use of transmission elements can be largely omitted and their number reduced to a minimum.
Consequently, the use of adjustable or endless transmission elements such as gear mechanisms or belts is no longer required, since the torque is transmitted directly from the drive to the cutting disc holder via the drive shaft.
Because of the direct coupling of the drive to the cutting disc holder, it is necessary for the drive to be arranged in the region of the rotational axis of the cutting disc or cutting disc holder. This has the advantage that the abrasive cutter has an optimal weight distribution, since the center of gravity of the abrasive cutter is shifted in the direction of the rotational axis. This allows through-cutting of the rail of the track in a reliable, efficient and at the same time user-friendly fashion, Date Recue/Date Received 2021-11-24
Because of the comparatively low weight, the abrasive cutter is user-friendly and easy to guide. The drive or electric drive motor, because of its compactness, guarantees that the cutting depth is not reduced.
Because of the direct coupling of the drive, the use of transmission elements can be largely omitted and their number reduced to a minimum.
Consequently, the use of adjustable or endless transmission elements such as gear mechanisms or belts is no longer required, since the torque is transmitted directly from the drive to the cutting disc holder via the drive shaft.
Because of the direct coupling of the drive to the cutting disc holder, it is necessary for the drive to be arranged in the region of the rotational axis of the cutting disc or cutting disc holder. This has the advantage that the abrasive cutter has an optimal weight distribution, since the center of gravity of the abrasive cutter is shifted in the direction of the rotational axis. This allows through-cutting of the rail of the track in a reliable, efficient and at the same time user-friendly fashion, Date Recue/Date Received 2021-11-24
- 5 -The term "directly coupled" in particular means avoiding transmission elements as far as possible, or reducing these to a minimum. In addition, the term includes in particular an indirect or direct intermeshing, in particular an indirect or direct contact, of the cutting disc holder with the drive shaft.
The term "directly coupled" in particular excludes the use of endless transmission elements in the form of belts or chains, and the use of gear mechanisms, in particular adjustable gears which allow the setting of different translation ratios.
Advantageously, a translation ratio n is formed between the drive shaft and the cutting disc holder, wherein in particular n = 1. A translation ratio of n ¨ I means that the electric drive motor is configured to have the rotational speed of the cutting disc. The translation ration is fixed, i.e. cannot be changed or adjusted.
The cutting disc is here actively connected to the cutting disc holder via at least one clamping element, whereby rotation of the cutting disc holder causes a rotation of the cutting disc. The at least one clamping element serves for fixing the cutting disc to the cutting disc holder. In particular, it is possible that the at least one clamping element is attached directly to the cutting disc holder, and the cutting disc is attached or clamped to the at least one clamping element. Thus the cutting disc is actively connected to the cutting disc holder indirectly via the at least one clamping element. The at least one clamping element may however also be configured such that the cutting disc can be attached directly thereby to the cutting disc holder.
Advantageously, the at least one clamping element is attached to the cutting disc holder via a clamping element holder.
Date Recue/Date Received 2021-11-24
The term "directly coupled" in particular excludes the use of endless transmission elements in the form of belts or chains, and the use of gear mechanisms, in particular adjustable gears which allow the setting of different translation ratios.
Advantageously, a translation ratio n is formed between the drive shaft and the cutting disc holder, wherein in particular n = 1. A translation ratio of n ¨ I means that the electric drive motor is configured to have the rotational speed of the cutting disc. The translation ration is fixed, i.e. cannot be changed or adjusted.
The cutting disc is here actively connected to the cutting disc holder via at least one clamping element, whereby rotation of the cutting disc holder causes a rotation of the cutting disc. The at least one clamping element serves for fixing the cutting disc to the cutting disc holder. In particular, it is possible that the at least one clamping element is attached directly to the cutting disc holder, and the cutting disc is attached or clamped to the at least one clamping element. Thus the cutting disc is actively connected to the cutting disc holder indirectly via the at least one clamping element. The at least one clamping element may however also be configured such that the cutting disc can be attached directly thereby to the cutting disc holder.
Advantageously, the at least one clamping element is attached to the cutting disc holder via a clamping element holder.
Date Recue/Date Received 2021-11-24
- 6 -An advantageous embodiment comprises a first and a second clamping element, between which a cutting disc can be attached by clamping. The first and second clamping elements comprise for example, starting from the rotational axis in the direction of their respective outer edge, a deformation which runs towards the clamping disc and is sprung. This allows clamping discs of different thickness to be attached with vibration damping by means of the at least one clamping element.
It is possible that, in addition to the at least one clamping element, further elements are provided which are arranged between the cutting disc holder and the at least one clamping element, and/or between the at least one clamping element and the cutting disc.
The base body defines a base body plane G which runs through the base body and perpendicularly to the rotational axis. The base body plane G
defines a first and a second side of the base body which lie opposite each other.
Advantageously, the abrasive cutter comprises a control unit for controlling the drive, wherein by means of the control unit, in particular two different rotational directions of the drive can be set.
The abrasive cutter serves for manually guided through-cutting of a rail.
An abrasive cutter as claimed in claim 2 allows a reliable, efficient and low-maintenance through-cutting of the rail. Formed in one piece means that the cutting disc holder and the drive shaft are combined and inseparably connected together. The drive shaft and the cutting disc holder Date Recue/Date Received 2021-11-24
It is possible that, in addition to the at least one clamping element, further elements are provided which are arranged between the cutting disc holder and the at least one clamping element, and/or between the at least one clamping element and the cutting disc.
The base body defines a base body plane G which runs through the base body and perpendicularly to the rotational axis. The base body plane G
defines a first and a second side of the base body which lie opposite each other.
Advantageously, the abrasive cutter comprises a control unit for controlling the drive, wherein by means of the control unit, in particular two different rotational directions of the drive can be set.
The abrasive cutter serves for manually guided through-cutting of a rail.
An abrasive cutter as claimed in claim 2 allows a reliable, efficient and low-maintenance through-cutting of the rail. Formed in one piece means that the cutting disc holder and the drive shaft are combined and inseparably connected together. The drive shaft and the cutting disc holder Date Recue/Date Received 2021-11-24
- 7 -accordingly form a common shaft. Consequently, the drive torque is transmitted to the at least one clamping element and hence to the cutting disc solely via a shaft. This has the advantage that fewer components, in particular fewer wearing parts, are fitted in the abrasive cutter.
An abrasive cutter as claimed in claim 3 allows an efficient and low-maintenance through-cutting of the rail. A two-part design has the advantage that the cutting disc holder and the drive shaft can be replaced individually. Formed in two parts means that the drive shaft and the cutting disc holder are independent elements. The drive shaft and the cutting disc holder are actively connected together directly or indirectly at an engagement region. In particular, the drive shaft and the cutting disc holder may have a toothing in the engagement region, via which the drive shaft and the cutting disc holder make direct contact. The drive shaft and the cutting disc holder are connected together rotationally fixedly.
The drive shaft and the cutting disc holder are preferably actively connected together at the engagement region in a rotationally fixed or form-fit fashion via a connection which is secure against twisting.
Advantageously, the direct active connection between the drive shaft and the cutting disc holder may be configured in form-fit fashion. In particular, at the engagement region, the drive shaft may be formed as a hollow shaft with internal toothing, while the cutting disc holder has external toothing which directly engages in the internal toothing of the drive shaft formed as a hollow shaft. It is also possible that the cutting disc holder is formed as a hollow shaft in the engagement region and has an internal toothing, wherein the drive shaft has an external toothing which engages in the internal toothing of the cutting disc holder formed as a hollow shaft.
Alternatively, the active connection between the drive shaft and the cutting Date Recue/Date Received 2021-11-24
An abrasive cutter as claimed in claim 3 allows an efficient and low-maintenance through-cutting of the rail. A two-part design has the advantage that the cutting disc holder and the drive shaft can be replaced individually. Formed in two parts means that the drive shaft and the cutting disc holder are independent elements. The drive shaft and the cutting disc holder are actively connected together directly or indirectly at an engagement region. In particular, the drive shaft and the cutting disc holder may have a toothing in the engagement region, via which the drive shaft and the cutting disc holder make direct contact. The drive shaft and the cutting disc holder are connected together rotationally fixedly.
The drive shaft and the cutting disc holder are preferably actively connected together at the engagement region in a rotationally fixed or form-fit fashion via a connection which is secure against twisting.
Advantageously, the direct active connection between the drive shaft and the cutting disc holder may be configured in form-fit fashion. In particular, at the engagement region, the drive shaft may be formed as a hollow shaft with internal toothing, while the cutting disc holder has external toothing which directly engages in the internal toothing of the drive shaft formed as a hollow shaft. It is also possible that the cutting disc holder is formed as a hollow shaft in the engagement region and has an internal toothing, wherein the drive shaft has an external toothing which engages in the internal toothing of the cutting disc holder formed as a hollow shaft.
Alternatively, the active connection between the drive shaft and the cutting Date Recue/Date Received 2021-11-24
- 8 -disc holder may be formed via a connecting component, for example a feather key.
An abrasive cutter as claimed in claim 4 allows a particularly reliable and efficient through-cutting of the rail. Advantageously, the drive comprises a housing by means of which the drive can be fixed via fixing means to a fixing region of the base body. Advantageously, damping elements are arranged between the housing and the fixing region, which reduces the transmission of vibrations from the drive to the base body. The fixing region is in particular arranged on a first side of the base body which is opposite the second side of the base body on which the cutting disc is arranged or can be fixed. The fixing region in particular has a width b which is smaller than the maximum width B of the base body. Thus the drive is arranged closer to the base body, which counters a shift in the center of gravity of the abrasive cutter in the direction of the first side.
In particular, for the width b of the fixing region, b < 0.3 = B, in particular b <
0.2 = B, advantageously b < 0.1 = B and/orb> 0.05 - B. Preferably, a base body plane G runs perpendicularly to the rotational axis through the base body. The base body plane G in particular runs through the fixing region.
The base body plane G defines the first side and the second side of the base body. The drive is preferably arranged on the first side, whereas a cutting disc can be attached to the cutting disc holder on the second side.
An abrasive cutter as claimed in claim 5 allows an efficient and user-friendly through-cutting of the rail. Because the second bearing is arranged outside the housing and in the base body, in particular on the fixing region, the drive is arranged closer to the base body plane, which counters a shift Date Recue/Date Received 2021-11-24
An abrasive cutter as claimed in claim 4 allows a particularly reliable and efficient through-cutting of the rail. Advantageously, the drive comprises a housing by means of which the drive can be fixed via fixing means to a fixing region of the base body. Advantageously, damping elements are arranged between the housing and the fixing region, which reduces the transmission of vibrations from the drive to the base body. The fixing region is in particular arranged on a first side of the base body which is opposite the second side of the base body on which the cutting disc is arranged or can be fixed. The fixing region in particular has a width b which is smaller than the maximum width B of the base body. Thus the drive is arranged closer to the base body, which counters a shift in the center of gravity of the abrasive cutter in the direction of the first side.
In particular, for the width b of the fixing region, b < 0.3 = B, in particular b <
0.2 = B, advantageously b < 0.1 = B and/orb> 0.05 - B. Preferably, a base body plane G runs perpendicularly to the rotational axis through the base body. The base body plane G in particular runs through the fixing region.
The base body plane G defines the first side and the second side of the base body. The drive is preferably arranged on the first side, whereas a cutting disc can be attached to the cutting disc holder on the second side.
An abrasive cutter as claimed in claim 5 allows an efficient and user-friendly through-cutting of the rail. Because the second bearing is arranged outside the housing and in the base body, in particular on the fixing region, the drive is arranged closer to the base body plane, which counters a shift Date Recue/Date Received 2021-11-24
- 9 -in the center of gravity of the abrasive cutter in the direction of the first side.
An abrasive cutter as claimed in claim 6 allows a particularly efficient and low-maintenance through-cutting of the rail. Because the first and second bearings are arranged inside the housing of the drive, it is guaranteed that the drive can be replaced quickly and easily. In addition, the forces occurring during cutting of the rail are transmitted to the base body via the housing of the drive.
An abrasive curter as claimed in claim 7 allows a particularly reliable and efficient through-cutting of the rail. The brushless electric motor requires little maintenance. Because of the brushless electric motor, it is guaranteed that the drive has a small transverse extent E and hence a substantially higher power density or specific power Ps,. In particular, for the power density Pspez of the brushless electric motor, Ps? 0.5 kW/kg, in particular Pspez > 0.8 kW/kg, and in particular Pspez > 1.0 kW/kg. The brushless electric motor is in particular a BLDC motor.
An abrasive cutter as claimed in claim 8 allows a particularly reliable and efficient through-cutting of the rail. The higher the power density Ps, the smaller and/or lighter the electric drive motor.
An abrasive cutter as claimed in claim 9 allows a particularly reliable and efficient through-cutting of the rail. The at least one temperature sensor serves to determine a temperature of the drive and/or the control unit during operation. The at least one determined temperature serves to avoid overheating of the abrasive cutter, in particular the drive or electric drive motor and/or the control unit, during through-cutting of a rail. Preferably, a Date Recue/Date Received 2021-11-24
An abrasive cutter as claimed in claim 6 allows a particularly efficient and low-maintenance through-cutting of the rail. Because the first and second bearings are arranged inside the housing of the drive, it is guaranteed that the drive can be replaced quickly and easily. In addition, the forces occurring during cutting of the rail are transmitted to the base body via the housing of the drive.
An abrasive curter as claimed in claim 7 allows a particularly reliable and efficient through-cutting of the rail. The brushless electric motor requires little maintenance. Because of the brushless electric motor, it is guaranteed that the drive has a small transverse extent E and hence a substantially higher power density or specific power Ps,. In particular, for the power density Pspez of the brushless electric motor, Ps? 0.5 kW/kg, in particular Pspez > 0.8 kW/kg, and in particular Pspez > 1.0 kW/kg. The brushless electric motor is in particular a BLDC motor.
An abrasive cutter as claimed in claim 8 allows a particularly reliable and efficient through-cutting of the rail. The higher the power density Ps, the smaller and/or lighter the electric drive motor.
An abrasive cutter as claimed in claim 9 allows a particularly reliable and efficient through-cutting of the rail. The at least one temperature sensor serves to determine a temperature of the drive and/or the control unit during operation. The at least one determined temperature serves to avoid overheating of the abrasive cutter, in particular the drive or electric drive motor and/or the control unit, during through-cutting of a rail. Preferably, a Date Recue/Date Received 2021-11-24
- 10 -temperature sensor is arranged on the drive, in particular inside a housing.
The temperature sensor is in particular arranged on the electric drive motor.
In addition or alternatively, a temperature sensor is preferably arranged on the control unit. The respective temperature sensor is in particular in signal connection with a warning element and/or the control unit. If a critical temperature of the drive and/or control unit is established by means of the respective temperature sensor, at least one countermeasure may be taken.
Possible countermeasures are for example actuating the warning element to warn an operator, and/or reducing the consumable or emittable power of the electric drive motor, and/or shutting down the electric drive motor.
An abrasive cutter as claimed in claim 10 allows a particularly reliable and efficient through-cutting of a rail. Because the control unit actuates the drive or electric drive motor depending on a determined temperature, a simple temperature monitoring may be achieved. If the temperature sensor determines a temperature which exceeds a critical temperature or temperature limit value, by means of the control unit at least one countermeasure may be initiated. Possible countermeasures are for example actuating the warning element to warn an operator, reducing the consumable or emittable power of the electric drive motor, and/or shutting down the electric drive motor. The at least one countermeasure is active temporarily.
An abrasive cutter as claimed in claim 11 allows a particularly reliable and efficient through-cutting of a rail. If a determined temperature exceeds a first temperature limit value TG1, a further temperature rise can be countered by reducing the emittable or consumable power of the electric drive motor. The heat generated by the electric drive motor is reduced so that the electric drive motor and/or the control unit can cool down. The Date Recue/Date Received 2021-11-24
The temperature sensor is in particular arranged on the electric drive motor.
In addition or alternatively, a temperature sensor is preferably arranged on the control unit. The respective temperature sensor is in particular in signal connection with a warning element and/or the control unit. If a critical temperature of the drive and/or control unit is established by means of the respective temperature sensor, at least one countermeasure may be taken.
Possible countermeasures are for example actuating the warning element to warn an operator, and/or reducing the consumable or emittable power of the electric drive motor, and/or shutting down the electric drive motor.
An abrasive cutter as claimed in claim 10 allows a particularly reliable and efficient through-cutting of a rail. Because the control unit actuates the drive or electric drive motor depending on a determined temperature, a simple temperature monitoring may be achieved. If the temperature sensor determines a temperature which exceeds a critical temperature or temperature limit value, by means of the control unit at least one countermeasure may be initiated. Possible countermeasures are for example actuating the warning element to warn an operator, reducing the consumable or emittable power of the electric drive motor, and/or shutting down the electric drive motor. The at least one countermeasure is active temporarily.
An abrasive cutter as claimed in claim 11 allows a particularly reliable and efficient through-cutting of a rail. If a determined temperature exceeds a first temperature limit value TG1, a further temperature rise can be countered by reducing the emittable or consumable power of the electric drive motor. The heat generated by the electric drive motor is reduced so that the electric drive motor and/or the control unit can cool down. The Date Recue/Date Received 2021-11-24
- 11 -emittable power is preferably reduced provisionally or temporarily. This is achieved in particular depending on a predefined duration and/or depending on the temperature falling below a predefined temperature limit value. The limit value below which the temperature must fall here may be equal to or lower than the first temperature limit value TG 1. Preferably, for the first temperature limit value TG 1, 80 C < Tc_;1 < 120 C, in particular 90 C < Tcjj 110 . For the maximum emittable or consumable reduced power PR, in particular 0.5 = P < PR < P, in particular 0.6 = P < PR < 0.9 =
P, and in particular 0.7 = P < PR < 0.8 = P.
If a second temperature limit value TG2 is exceeded, the electric drive motor is shut down. This shut-down occurs in particular if a reduction in the emittable power of the abrasive cutter was unsuccessful. Preferably, the second temperature limit value TG2 is higher than the first temperature limit value TG1. Preferably, for the second temperature limit value TG2, 110 C
TG, < 140 C, in particular 120 C < TG2 < 130 C. The electric drive motor is in particular shut down provisionally or temporarily. The temporary shut-down takes place for example depending on a predefined duration and/or depending on the temperature falling below a predefined temperature limit value. This limit value below which the temperature must fall may be equal to or lower than the second temperature limit value TG2.
Preferably, the limit value below which the temperature must fall is lower than the first temperature limit value TGI.
When cutting through a rail, the control unit is preferably configured such that the electric drive motor is operated at least temporarily with a power PB for which P < PB <4 = P, in particular 1.5 - P < PB < 3.5 - P, and in particular 2 = P < .PB < 3 = P. P designates a nominal power of the electric drive motor.
Date Recue/Date Received 2021-11-24
P, and in particular 0.7 = P < PR < 0.8 = P.
If a second temperature limit value TG2 is exceeded, the electric drive motor is shut down. This shut-down occurs in particular if a reduction in the emittable power of the abrasive cutter was unsuccessful. Preferably, the second temperature limit value TG2 is higher than the first temperature limit value TG1. Preferably, for the second temperature limit value TG2, 110 C
TG, < 140 C, in particular 120 C < TG2 < 130 C. The electric drive motor is in particular shut down provisionally or temporarily. The temporary shut-down takes place for example depending on a predefined duration and/or depending on the temperature falling below a predefined temperature limit value. This limit value below which the temperature must fall may be equal to or lower than the second temperature limit value TG2.
Preferably, the limit value below which the temperature must fall is lower than the first temperature limit value TGI.
When cutting through a rail, the control unit is preferably configured such that the electric drive motor is operated at least temporarily with a power PB for which P < PB <4 = P, in particular 1.5 - P < PB < 3.5 - P, and in particular 2 = P < .PB < 3 = P. P designates a nominal power of the electric drive motor.
Date Recue/Date Received 2021-11-24
- 12 -An abrasive cutter as claimed in claim 12 guarantees a reliable and efficient through-cutting of a rail. The cooling system is in particular configured as an active cooling system which produces a movement of a cooling fluid. Preferably, the cooling system comprises at least one cooling element which can be or is driven. The at least one cooling element serves in particular to produce the movement of the cooling fluid. Preferably, the at least one cooling element comprises a fan wheel. The fan wheel in particular generates an air stream for cooling the drive or electric drive motor and/or control unit. The at least one cooling element can be driven by means of the electric drive motor and/or by means of its own drive motor. Preferably, the at least one cooling element is attached to the drive axis of the electric drive motor and/or to the cutting disc holder.
Preferably, the at least one cooling element is arranged on a side of the electric drive motor facing the cutting disc and/or on a side of the electric drive motor facing away from the cutting disc, concentrically to the drive axis or rotational axis. Preferably, the abrasive cutter comprises a fan, in particular an axial fan, with a fan wheel and an associated drive motor. The fan is for example arranged on the base body for cooling the control unit and/or for cooling the drive, and/or on the control unit and/or on the drive.
The invention is furthermore based on the object of creating a simple, reliable, user-friendly and efficient method for cutting through a rail of a track.
This object is achieved by a method with the features of claim 13. The advantages of the method according to the invention correspond to the advantages of the abrasive cutter according to the invention as already described. The method according to the invention may in particular be Date Recue/Date Received 2021-11-24
Preferably, the at least one cooling element is arranged on a side of the electric drive motor facing the cutting disc and/or on a side of the electric drive motor facing away from the cutting disc, concentrically to the drive axis or rotational axis. Preferably, the abrasive cutter comprises a fan, in particular an axial fan, with a fan wheel and an associated drive motor. The fan is for example arranged on the base body for cooling the control unit and/or for cooling the drive, and/or on the control unit and/or on the drive.
The invention is furthermore based on the object of creating a simple, reliable, user-friendly and efficient method for cutting through a rail of a track.
This object is achieved by a method with the features of claim 13. The advantages of the method according to the invention correspond to the advantages of the abrasive cutter according to the invention as already described. The method according to the invention may in particular be Date Recue/Date Received 2021-11-24
- 13 -refined by at least one feature which has been described in connection with the abrasive cutter according to the invention. When cutting through a rail, the electric drive motor is preferably operated at least temporarily with a power PB for which P < PB < 4 P, in particular 1.5 - P < PB < 3.5 = P. and in particular 2 P PB < 3 = P, wherein P designates a nominal power of the electric drive motor.
Further features, advantages and details of the invention arise from the following description of several exemplary embodiments. The drawings show:
Fig. I a perspective view of an abrasive cutter according to a first exemplary embodiment, Fig. 2 a top view of the abrasive cutter from figure 1, Fig. 3 a side view of the abrasive cutter from figure 1, Fig. 4 a rear view of the abrasive cutter from figure 1, Fig. 5 a section through the abrasive cutter along Line V-V in figure 2, Fig. 6 a section through an abrasive cutter according to a second exemplary embodiment, Fig. 7 a side view of an abrasive cutter according to a third exemplary embodiment, Date Recue/Date Received 2021-11-24
Further features, advantages and details of the invention arise from the following description of several exemplary embodiments. The drawings show:
Fig. I a perspective view of an abrasive cutter according to a first exemplary embodiment, Fig. 2 a top view of the abrasive cutter from figure 1, Fig. 3 a side view of the abrasive cutter from figure 1, Fig. 4 a rear view of the abrasive cutter from figure 1, Fig. 5 a section through the abrasive cutter along Line V-V in figure 2, Fig. 6 a section through an abrasive cutter according to a second exemplary embodiment, Fig. 7 a side view of an abrasive cutter according to a third exemplary embodiment, Date Recue/Date Received 2021-11-24
- 14 -Fig. 8 a section through the abrasive cutter along cut line .. in figure 7, and Fig. 9 a section through the abrasive cutter along cut line IX-1X
in figure 7.
Figures 1 to 5 show an abrasive cutter 1 according to a first exemplary embodiment. The abrasive cutter I serves for cutting through a rail of a track. For reasons of clarity, the track is not depicted in the figures.
Figures 1 to 4 show the abrasive cutter comprising a base body 2, a drive 4 with the drive axis A1, and a cutting disc 5. The drive 4 serves to drive the cutting disc 4 about a rotational axis A2. According to the exemplary embodiment depicted, the rotational axis A2 and the drive axis Ai arc aligned. The rotational axis A2 is therefore identical to the drive axis Ai.
The base body 2 has a pivotable handle 8 for holding and manually guiding the abrasive cutter 1. The base body 2 defines a base body plane G which runs through the base body 2 and perpendicularly to the rotational axis A2.
The drive 4 and the cutting disc 5 are arranged on different sides of the base body plane G. The drive 4 is arranged on a first side G1 of the base body 2, while the cutting disc 5 is arranged on a second side G2 of the base body 2. The first side GI lies opposite the second side G2.
The drive 4 has a housing 9 via which the drive 4 is fixed to the base body 2 in a fixing region 16 by fixing means 17. The fixing means 17 are in particular visible in figure 5. In comparison with a maximum width B of the base body 2, the fixing region 16 has a substantially smaller width h.
For the width b, b < 0.1 B. Because the fixing region 16 has such a Date Recue/Date Received 2021-11-24
in figure 7.
Figures 1 to 5 show an abrasive cutter 1 according to a first exemplary embodiment. The abrasive cutter I serves for cutting through a rail of a track. For reasons of clarity, the track is not depicted in the figures.
Figures 1 to 4 show the abrasive cutter comprising a base body 2, a drive 4 with the drive axis A1, and a cutting disc 5. The drive 4 serves to drive the cutting disc 4 about a rotational axis A2. According to the exemplary embodiment depicted, the rotational axis A2 and the drive axis Ai arc aligned. The rotational axis A2 is therefore identical to the drive axis Ai.
The base body 2 has a pivotable handle 8 for holding and manually guiding the abrasive cutter 1. The base body 2 defines a base body plane G which runs through the base body 2 and perpendicularly to the rotational axis A2.
The drive 4 and the cutting disc 5 are arranged on different sides of the base body plane G. The drive 4 is arranged on a first side G1 of the base body 2, while the cutting disc 5 is arranged on a second side G2 of the base body 2. The first side GI lies opposite the second side G2.
The drive 4 has a housing 9 via which the drive 4 is fixed to the base body 2 in a fixing region 16 by fixing means 17. The fixing means 17 are in particular visible in figure 5. In comparison with a maximum width B of the base body 2, the fixing region 16 has a substantially smaller width h.
For the width b, b < 0.1 B. Because the fixing region 16 has such a Date Recue/Date Received 2021-11-24
- 15 -smaller width b, the drive 4 is arranged substantially closer to the base body 2, which counters a shift in the center of gravity of the abrasive cutter 1 in the direction of the first side G1.
To control spark emission and protect an operator, a spark protection 7 is arranged on the base body 2 and partially surrounds the cutting disc 5.
Figure 5 shows a section through the abrasive cutter 1 along cut line V-V
in figure 2. In the exemplary embodiment shown, the cutting disc 5 is arranged on a cutting disc holder 3 via a first clamping element 13a and a second clamping element 13b. The clamping elements 13a and 13b each have a same diameter D. The cutting disc 5 is thus arranged between the two clamping elements 13a and 13b on the cutting disc holder 3 and attached thereto.
The spark protection 7 and the clamping element 13a and 13b define a cutting region 6 which is formed on a region of the cutting disc 5 that is not surrounded by the spark protection 7 or the first clamping element 13a or second clamping element 13b. The cutting region 6 is the region in which the cutting disc 5 comes or may come into contact with the rail (not shown) during the cutting process. The cutting region 6 forms a plane of symmetry ST
The second clamping element 13b has a passage opening via which this can be pushed onto the cutting disc holder 3 and thus come to rest against a stop 20 of the cutting disc holder 3.
To attach the first clamping element 13a and hence attach the cutting disc 5 between the first and second clamping elements 13a and 13b, the cutting Date Recue/Date Received 2021-11-24
To control spark emission and protect an operator, a spark protection 7 is arranged on the base body 2 and partially surrounds the cutting disc 5.
Figure 5 shows a section through the abrasive cutter 1 along cut line V-V
in figure 2. In the exemplary embodiment shown, the cutting disc 5 is arranged on a cutting disc holder 3 via a first clamping element 13a and a second clamping element 13b. The clamping elements 13a and 13b each have a same diameter D. The cutting disc 5 is thus arranged between the two clamping elements 13a and 13b on the cutting disc holder 3 and attached thereto.
The spark protection 7 and the clamping element 13a and 13b define a cutting region 6 which is formed on a region of the cutting disc 5 that is not surrounded by the spark protection 7 or the first clamping element 13a or second clamping element 13b. The cutting region 6 is the region in which the cutting disc 5 comes or may come into contact with the rail (not shown) during the cutting process. The cutting region 6 forms a plane of symmetry ST
The second clamping element 13b has a passage opening via which this can be pushed onto the cutting disc holder 3 and thus come to rest against a stop 20 of the cutting disc holder 3.
To attach the first clamping element 13a and hence attach the cutting disc 5 between the first and second clamping elements 13a and 13b, the cutting Date Recue/Date Received 2021-11-24
- 16 -disc holder 3 has an axial bore 19 with internal thread in which a clamping element holder 18, in the form of a screw with an external thread, can be inserted. The first clamping element 13a for this has a passage opening through which the threaded portion of the clamping element holder 18 can be passed. The first clamping element 13a is fixed to an end 21 of the cutting disc holder 3 by the clamping element holder 18 after this has been screwed in.
The clamping elements 13a and 13b are configured such that they attach the cutting disc 5 by clamping, whereby on rotation of the cutting disc holder 3, the cutting disc 5 rotates via the two clamping elements. In the exemplary embodiment shown, the clamping elements 13a and 13b are each configured, starting from the rotary axis A2 in the direction of their outer edges 22a and 22b, such that they are deformed towards the cutting disc 5 and sprung. Because of this deformation, a plurality of different cutting discs with different widths can be attached by means of the clamping elements 13a and 13b, since these deform depending on the width of the cutting disc 5 to be mounted, but still have a corresponding clamping effect.
An electric drive motor 15 with a drive shaft 10 is arranged in the housing 9 of the drive 4. In the exemplary embodiment shown, the electric drive motor 15 is configured as a brushless electric motor. The electric drive motor 15 has a rotor which comprises the drive shaft 10 and permanent magnets arranged thereon. The electric drive motor 15 furthermore comprises a stator having several electromagnets. The permanent magnets and the electromagnets are not illustrated in detail in the figures. The electric drive motor 15 has a power density Ps pez > 0.5 kW/kg. The drive Date Recue/Date Received 2021-11-24
The clamping elements 13a and 13b are configured such that they attach the cutting disc 5 by clamping, whereby on rotation of the cutting disc holder 3, the cutting disc 5 rotates via the two clamping elements. In the exemplary embodiment shown, the clamping elements 13a and 13b are each configured, starting from the rotary axis A2 in the direction of their outer edges 22a and 22b, such that they are deformed towards the cutting disc 5 and sprung. Because of this deformation, a plurality of different cutting discs with different widths can be attached by means of the clamping elements 13a and 13b, since these deform depending on the width of the cutting disc 5 to be mounted, but still have a corresponding clamping effect.
An electric drive motor 15 with a drive shaft 10 is arranged in the housing 9 of the drive 4. In the exemplary embodiment shown, the electric drive motor 15 is configured as a brushless electric motor. The electric drive motor 15 has a rotor which comprises the drive shaft 10 and permanent magnets arranged thereon. The electric drive motor 15 furthermore comprises a stator having several electromagnets. The permanent magnets and the electromagnets are not illustrated in detail in the figures. The electric drive motor 15 has a power density Ps pez > 0.5 kW/kg. The drive Date Recue/Date Received 2021-11-24
- 17 -shaft 10 defines the drive axis Ai. The drive 4 is attached to the fixing region 16 of the base body 2 via the fixing means 17 in the form of bolts.
In the exemplary embodiment shown, the drive 4 has a maximum transverse extent E which is equal to the diameter D of the clamping elements 13a and 13b. The maximum extent E is defined perpendicularly to the drive axis Al in the plane of symmetry ST. Because the maximum transverse extent E of the drive 4 is at most equal to the diameter D of the clamping elements 13a and 13b, it is ensured that the drive 4 does not protrude into the cutting region 6 and hence reduce this. The abrasive cutter 1 serves for use of cutting discs 5 with a maximum nominal diameter DN.
The maximum nominal diameter DN is in particular established by the spark protection 7. In particular, E < 0.5 = DN.
In the exemplary embodiment shown, the drive shaft 10 is mounted on the housing 9 of the drive 4 via a first bearing 11, while the cutting disc holder 3 is mounted in the fixing region 16 of the base body 2 via a second bearing 12. The abrasive cutter I comprises a control unit 26 for actuating the drive 4.
In the exemplary embodiment shown, the drive shaft 10 of the drive 4 is configured as a hollow shaft in the engagement region 23, and has a receiving opening for receiving the cutting disc holder 3. The drive shaft 10 is connected by form fit to the cutting disc holder 3 by means of a feather key 14, whereby the drive 4 is directly coupled to the cutting disc holder 3 via the drive shaft 10. On rotation of the drive shaft 10, therefore, the cutting disc holder 3 also rotates. The culling disc holder 3 defines the rotational axis A2.
Date Recue/Date Received 2021-11-24
In the exemplary embodiment shown, the drive 4 has a maximum transverse extent E which is equal to the diameter D of the clamping elements 13a and 13b. The maximum extent E is defined perpendicularly to the drive axis Al in the plane of symmetry ST. Because the maximum transverse extent E of the drive 4 is at most equal to the diameter D of the clamping elements 13a and 13b, it is ensured that the drive 4 does not protrude into the cutting region 6 and hence reduce this. The abrasive cutter 1 serves for use of cutting discs 5 with a maximum nominal diameter DN.
The maximum nominal diameter DN is in particular established by the spark protection 7. In particular, E < 0.5 = DN.
In the exemplary embodiment shown, the drive shaft 10 is mounted on the housing 9 of the drive 4 via a first bearing 11, while the cutting disc holder 3 is mounted in the fixing region 16 of the base body 2 via a second bearing 12. The abrasive cutter I comprises a control unit 26 for actuating the drive 4.
In the exemplary embodiment shown, the drive shaft 10 of the drive 4 is configured as a hollow shaft in the engagement region 23, and has a receiving opening for receiving the cutting disc holder 3. The drive shaft 10 is connected by form fit to the cutting disc holder 3 by means of a feather key 14, whereby the drive 4 is directly coupled to the cutting disc holder 3 via the drive shaft 10. On rotation of the drive shaft 10, therefore, the cutting disc holder 3 also rotates. The culling disc holder 3 defines the rotational axis A2.
Date Recue/Date Received 2021-11-24
- 18 -The function of the abrasive cutter 1 is as follows:
Firstly, the cutting disc 5 is mounted on the cutting disc holder 3 by the clamping elements 13a and 13b. For this, the second clamping clement 13b is pushed onto the cutting disc holder 3 and bears on the stop 20. Then the cutting disc 5 is pushed onto the cutting disc holder 3. Then the first clamping element 13a is fixed to the cutting disc holder 3 by means of the clamping element holder 18, whereby the cutting disc 5 is clamped between the two clamping elements 13a and I 3b. In this way, the cutting disc 5 is actively connected to the cutting disc holder 3. The drive shaft 10 is set in rotation by the control unit 26 which serves to control the drive 4.
Because the drive shaft 10 is coupled directly to the cutting disc holder 3 by the feather key 14, the rotary motion of the drive shaft 10 is directly transmitted to the cutting disc holder 3. Since the cutting disc 5 is actively connected to the cutting disc holder 3 via the clamping elements 13a and 13b, the rotary motion of the cutting disc holder 3 is transmitted to the cutting disc 5. During the cutting process, the cutting disc 5 is successively worn away, reducing the diameter of the cutting disc 5. Because the maximum transverse extent E of the drive 4 is at most equal to the diameter D of the clamping elements 13a and 13b, the useful cutting region 6 extends up to the clamping elements 13a and 13b.
The electric drive motor 15 can be driven in rotation in different rotational directions by means of the control unit 26. The rotational direction may be set manually and/or automatically. The rotational direction is set for example by means of at least one control switch, preferably by means of a respective control switch, and/or automatically as a function of a holding position of the abrasive cutter 1, for example by means of a sensor.
Date Recue/Date Received 2021-11-24
Firstly, the cutting disc 5 is mounted on the cutting disc holder 3 by the clamping elements 13a and 13b. For this, the second clamping clement 13b is pushed onto the cutting disc holder 3 and bears on the stop 20. Then the cutting disc 5 is pushed onto the cutting disc holder 3. Then the first clamping element 13a is fixed to the cutting disc holder 3 by means of the clamping element holder 18, whereby the cutting disc 5 is clamped between the two clamping elements 13a and I 3b. In this way, the cutting disc 5 is actively connected to the cutting disc holder 3. The drive shaft 10 is set in rotation by the control unit 26 which serves to control the drive 4.
Because the drive shaft 10 is coupled directly to the cutting disc holder 3 by the feather key 14, the rotary motion of the drive shaft 10 is directly transmitted to the cutting disc holder 3. Since the cutting disc 5 is actively connected to the cutting disc holder 3 via the clamping elements 13a and 13b, the rotary motion of the cutting disc holder 3 is transmitted to the cutting disc 5. During the cutting process, the cutting disc 5 is successively worn away, reducing the diameter of the cutting disc 5. Because the maximum transverse extent E of the drive 4 is at most equal to the diameter D of the clamping elements 13a and 13b, the useful cutting region 6 extends up to the clamping elements 13a and 13b.
The electric drive motor 15 can be driven in rotation in different rotational directions by means of the control unit 26. The rotational direction may be set manually and/or automatically. The rotational direction is set for example by means of at least one control switch, preferably by means of a respective control switch, and/or automatically as a function of a holding position of the abrasive cutter 1, for example by means of a sensor.
Date Recue/Date Received 2021-11-24
- 19 -With reference to figure 6, a second exemplary embodiment of the abrasive cutter 1 is described. In the second exemplary embodiment, the cutting disc holder 3 is formed in one piece with the drive shaft 10. The cutting disc holder 3 and the drive shaft 10 thus form a common shaft 24. Accordingly, the torque of the drive 4 is transmitted via the common shaft 24 to the first and second clamping elements 13a and 13b and hence to the cutting disc S.
The first bearing 11 and the second bearing 12 are supported on the housing 9. With respect to the further construction and further function, reference is made to the preceding exemplary embodiment.
A third exemplary embodiment of the invention is described below with reference to figures 7 to 9. The base body 2 is formed extremely compactly. First handles 8 are fixedly arranged on the base body 2. In addition, second handles 8 are arranged on the base body 2. The second handles 8' are formed cylindrically and extend spaced apart from and parallel to each other. The second handles 8' run substantially perpendicularly to the drive axis Al on a side of the base body 2 which faces away from the drive 4 relative to the first handles 8. The handles 8' are connected together and stabilized by means of a spacer 27.
The electric drive motor 15 is arranged in the housing 9. The housing 9 is configured in two parts. The housing 9 comprises a pot-like first housing component 28 and a lid-like second housing component 29. The first bearing 11 is mounted in the first housing component 28, while the second bearing 12 is mounted in the second housing component 29. The second housing component 29 is attached in the fixing region 16 and releasably connected to the first housing component 28. The drive shaft 10 is connected integrally to the cutting disc holder 3. The drive axis Ai and the rotational axis A2 are arranged coaxially to one another.
Date Recue/Date Received 2021-11-24
The first bearing 11 and the second bearing 12 are supported on the housing 9. With respect to the further construction and further function, reference is made to the preceding exemplary embodiment.
A third exemplary embodiment of the invention is described below with reference to figures 7 to 9. The base body 2 is formed extremely compactly. First handles 8 are fixedly arranged on the base body 2. In addition, second handles 8 are arranged on the base body 2. The second handles 8' are formed cylindrically and extend spaced apart from and parallel to each other. The second handles 8' run substantially perpendicularly to the drive axis Al on a side of the base body 2 which faces away from the drive 4 relative to the first handles 8. The handles 8' are connected together and stabilized by means of a spacer 27.
The electric drive motor 15 is arranged in the housing 9. The housing 9 is configured in two parts. The housing 9 comprises a pot-like first housing component 28 and a lid-like second housing component 29. The first bearing 11 is mounted in the first housing component 28, while the second bearing 12 is mounted in the second housing component 29. The second housing component 29 is attached in the fixing region 16 and releasably connected to the first housing component 28. The drive shaft 10 is connected integrally to the cutting disc holder 3. The drive axis Ai and the rotational axis A2 are arranged coaxially to one another.
Date Recue/Date Received 2021-11-24
- 20 -The drive motor 15 is configured as a brushless electric motor. The drive motor I 5 comprises a stator which is arranged rotationally fixedly relative to the housing 9. The stator 30 comprises electromagnets (not shown in detail) in the usual fashion. The stator 30 surrounds and delimits an interior in which a rotor 31 is arranged. The rotor 31 comprises permanent magnets 31 and the drive shaft 10 in the usual fashion. The permanent magnets 31' are attached, for example bonded, to the drive shaft 10. The rotor 31 may be driven in rotation about the drive axis A1 by means of the stator 30.
The abrasive cutter 1 comprises a first temperature sensor 32 which is arranged inside the housing 9 on the electric drive motor 15. The first temperature sensor 32 is in signal connection with the control unit 26, and transmits thereto measurement values of a first temperature T1 of the electric drive motor 15. The abrasive cutter 1 furthermore comprises a second temperature sensor 33. The second temperature sensor 33 is arranged on the control unit 26 and integrated together therewith in the base body 2. The second temperature sensor 33 is in signal connection with the control unit 26, and transmits thereto measurement values of a second temperature T, of the control unit 26.
In the control unit 26, a first temperature limit value TGI, for example 100 C, and a second temperature limit value T(i2, for example 120 C, are predefined. The control unit 26 repeatedly compares the measurement values of the first temperature T1 and the second temperature -1.2 with the temperature limit values Tc.ii and T62. If one of the temperatures Ti and/or T2 exceeds the first temperature limit value Ti, the consumable or emittable power PR of the abrasive cutter 1 is reduced. The abrasive cutter 1 has a nominal power of 2 kW < P < 3 kW, for example P 2.5 kW. If Date Recue/Date Received 2021-11-24
The abrasive cutter 1 comprises a first temperature sensor 32 which is arranged inside the housing 9 on the electric drive motor 15. The first temperature sensor 32 is in signal connection with the control unit 26, and transmits thereto measurement values of a first temperature T1 of the electric drive motor 15. The abrasive cutter 1 furthermore comprises a second temperature sensor 33. The second temperature sensor 33 is arranged on the control unit 26 and integrated together therewith in the base body 2. The second temperature sensor 33 is in signal connection with the control unit 26, and transmits thereto measurement values of a second temperature T, of the control unit 26.
In the control unit 26, a first temperature limit value TGI, for example 100 C, and a second temperature limit value T(i2, for example 120 C, are predefined. The control unit 26 repeatedly compares the measurement values of the first temperature T1 and the second temperature -1.2 with the temperature limit values Tc.ii and T62. If one of the temperatures Ti and/or T2 exceeds the first temperature limit value Ti, the consumable or emittable power PR of the abrasive cutter 1 is reduced. The abrasive cutter 1 has a nominal power of 2 kW < P < 3 kW, for example P 2.5 kW. If Date Recue/Date Received 2021-11-24
-21 -one of the temperatures T, and/or T2 exceeds the first temperature limit value TGI, the ernittable power PR is reduced by means of the control unit 26, for example to PR = 0.7 = P. The power is reduced for a predefined duration. If one of the temperatures T, and/or T2 exceeds the second temperature limit value TG2, the abrasive cutter 1 is shut down by means of the control unit 26. The shut-down takes place for predefined duration. In this way, a temperature monitoring is implemented and an overheating of the drive 4 and/or control unit 26 is avoided.
The abrasive cutter I comprises an active cooling system 34 for cooling the drive 4 and/or the control unit 26. The active cooling system 34 produced a movement of a cooling medium L. The cooling medium L in the present exemplary embodiment is air. The cooling system 34 comprises an inflow channel 35, a fan wheel 36 and an outflow channel 37. The fan wheel 36 is attached to the common shaft 24 between the electric drive motor 15 and the second clamping element 13b, and can be driven in rotation by means of the electric drive motor 15. The fan wheel 36 is for example formed in one piece with the second clamping element 13b. The inflow channel 35 is formed L-shaped in cross-section. The inflow channel 35 firstly runs between the base body 2 and the housing 9 in the direction of the drive axis Al. In the fixing region 16, the inflow channel 35 changes direction and in the fixing region 16 runs between the housing 9 and the second clamping element 13b. The inflow channel 35 runs up to the fan wheel 36. The aspirated air L changes its flow direction at the fan wheel 36 and passes over the fan wheel 36 in the direction of the drive axis A,. Then the outflow channel 37 begins. The outflow channel 37 runs from the fan wheel 36 between the base body 2 and the spark protection 7. The outflowing air L flows substantially perpendicularly to the drive axis Al.
Date Recue/Date Received 2021-11-24
The abrasive cutter I comprises an active cooling system 34 for cooling the drive 4 and/or the control unit 26. The active cooling system 34 produced a movement of a cooling medium L. The cooling medium L in the present exemplary embodiment is air. The cooling system 34 comprises an inflow channel 35, a fan wheel 36 and an outflow channel 37. The fan wheel 36 is attached to the common shaft 24 between the electric drive motor 15 and the second clamping element 13b, and can be driven in rotation by means of the electric drive motor 15. The fan wheel 36 is for example formed in one piece with the second clamping element 13b. The inflow channel 35 is formed L-shaped in cross-section. The inflow channel 35 firstly runs between the base body 2 and the housing 9 in the direction of the drive axis Al. In the fixing region 16, the inflow channel 35 changes direction and in the fixing region 16 runs between the housing 9 and the second clamping element 13b. The inflow channel 35 runs up to the fan wheel 36. The aspirated air L changes its flow direction at the fan wheel 36 and passes over the fan wheel 36 in the direction of the drive axis A,. Then the outflow channel 37 begins. The outflow channel 37 runs from the fan wheel 36 between the base body 2 and the spark protection 7. The outflowing air L flows substantially perpendicularly to the drive axis Al.
Date Recue/Date Received 2021-11-24
- 22 -The electric drive motor 15 can be driven in rotation by means of the control unit 26 in a first rotational direction di or in a second opposite rotational direction d2. To set the respective rotational direction di, d2, the abrasive cutter I has a first control switch Si and a second control switch S2. If the first control switch Si is actuated, the electric drive motor 15 is driven in rotation in the first rotational direction di. If however the second control switch S2 is actuated, the electric drive motor 15 is driven in rotation in the second rotational direction dz.
When cutting through a rail, the abrasive cutter I is operated with a power PB which is higher than the nominal power P. It takes between around 1 minute and 2 minutes to cut through a rail, so during this period the abrasive cutter I does not overheat. During rotation of the shaft 24, in particular during through-cutting of a rail, the electric drive motor 15 and the control unit 26 are cooled by means of the cooling system 34. If the abrasive cutter I is adequately cooled before cutting through a further rail, the further rail may be cut using the abrasive cutter 1 in the manner described without the abrasive cutter I overheating.
If the abrasive cutter 1 is greatly heated because of repeated cutting processes, then a safe operation of the abrasive cutter I is guaranteed by the temperature monitoring. If one of the temperatures Ti and/or T., exceeds the first temperature limit value TG1, initially the power PB is reduced to the power PR and the abrasive cutter I is operated with the reduced power PR. This avoids further heating of the abrasive cutter 1 and subsequent overheating. If however one of the temperatures T1 and/or T2 exceeds the second temperature limit value TG2, the abrasive cutter I is shut down temporarily. With respect to the further structure and further function, reference is made to the preceding exemplary embodiments.
Date Recue/Date Received 2021-11-24
When cutting through a rail, the abrasive cutter I is operated with a power PB which is higher than the nominal power P. It takes between around 1 minute and 2 minutes to cut through a rail, so during this period the abrasive cutter I does not overheat. During rotation of the shaft 24, in particular during through-cutting of a rail, the electric drive motor 15 and the control unit 26 are cooled by means of the cooling system 34. If the abrasive cutter I is adequately cooled before cutting through a further rail, the further rail may be cut using the abrasive cutter 1 in the manner described without the abrasive cutter I overheating.
If the abrasive cutter 1 is greatly heated because of repeated cutting processes, then a safe operation of the abrasive cutter I is guaranteed by the temperature monitoring. If one of the temperatures Ti and/or T., exceeds the first temperature limit value TG1, initially the power PB is reduced to the power PR and the abrasive cutter I is operated with the reduced power PR. This avoids further heating of the abrasive cutter 1 and subsequent overheating. If however one of the temperatures T1 and/or T2 exceeds the second temperature limit value TG2, the abrasive cutter I is shut down temporarily. With respect to the further structure and further function, reference is made to the preceding exemplary embodiments.
Date Recue/Date Received 2021-11-24
- 23 -In general:
The abrasive cutter I may bc connected to an external energy supply unit by means of an energy supply connection, and/or may comprise its own energy supply unit. An energy supply unit may for example be an accumulator or an accumulator arrangement. The energy supply unit may for example be attached to the base body 2 and/or be integrated in the base body 2. Preferably, the energy supply unit 2 can be recharged and/or exchanged.
Date Recue/Date Received 2021-11-24
The abrasive cutter I may bc connected to an external energy supply unit by means of an energy supply connection, and/or may comprise its own energy supply unit. An energy supply unit may for example be an accumulator or an accumulator arrangement. The energy supply unit may for example be attached to the base body 2 and/or be integrated in the base body 2. Preferably, the energy supply unit 2 can be recharged and/or exchanged.
Date Recue/Date Received 2021-11-24
Claims (13)
1. An abrasive cutter (1) for cutting through a rail of a track, with - a base body (2), - a cutting disc holder (3) for mounting a cutting disc (5), and - a drive (4) for driving the cutting disc hokler (3) in rotation about a rotational axis (A2), wherein -- the drive (4) is directly coupled to the cutting disc holder (3), -- the drive (4) cornprises an electric drive motor (15), -- a drive axis (Ai) of the electric drive motor (4) and the rotational axis (A2) align, characterized in that the drive (4) has a maximum transverse extent (E) which is at most equal to a diameter (D) of at least one clamping element (13) for fixing the cutting disc (5) to the cutting disc holder (3), and the electric drive motor (15) has a power density P
- Spcz, wherein Pspez >
0.5 kW/kg.
- Spcz, wherein Pspez >
0.5 kW/kg.
2. The abrasive cutter as claimed in claim 1, characterized in that a drive shaft (10) of the electric drive motor (15) is forrned in one piece with the cutting disc holder (3).
3. The abrasive cutter as claimed in claim 1, characterized in that a drive shaft (10) of the electric drive motor (15) and the cutting disc holder (3) are forrned in two pieces.
4. The abrasive cutter as claimed in any of clairns 1 to 3, characterized in that the drive (4) is arranged on the base body (2), in particular on a first side (G1) of the base body (2).
S. The abrasive cutter as claimed in any of clairns 1 to 4, characterized in that a first bearing (11) is supported on a housing (9) of the drive (4) and a second bearing (12) is supported on the base body (2).
6. The abrasive cutter as claimed in any of claims 1 to 5, characterized in that a first bearing (11) and a second bearing (12) are supported on a housing (9) of the drive (4).
7. The abrasive cutter as claimed in any of claims 1 to 6, characterized in that the electric drive motor (15) is configured as a brushless electric motor.
8. The abrasive cutter as claimed in any of claims 1 to 7, characterized in that for the power density Pspu applies: Pspe, 0.8 l(W/kg, and in particular Pspcz > 1.0 kW/kg.
9. The abrasive cutter as claimed in any of clairns 1 to 8, characterized by at least one temperature sensor (32, 33) for deterrnining a temperature (T1) of the drive (4) and/or a ternperature (T) of a control unit (26).
10. The abrasive cutter as claimed in any of claims 1 to 9, characterized by a control unit (26) for controlling the drive (4), in particular depending on a determined temperature (T1, T,).
11. The abrasive cutter as claimed in any of clairns 1 to 10, characterized by a control unit (26) which is configured such that an emittable power (PR) of the electric drive rnotor (15) is reduced when a determined temperature (Ti, T2) exceeds a first ternperature limit value (Tcri), and/or such that the electric drive rnotor (15) is shut down when a deterrnined temperature (Ti, T2) exceeds a second temperature limit value (T(2).
12. The abrasive cutter as claimed in any of claims 1 to 11, characterized by a cooling system (34) for cooling the electric drive motor (15) and/or a control unit (26).
13. A method for cutting through a rail of a track, with the steps:
- providing an abrasive cutter (1) as claimed in at least one of clairns 1 to 12, and - cutting through the rail by means of a cutting disc (5) which is driven in rotation by means of the abrasive cutter (1).
- providing an abrasive cutter (1) as claimed in at least one of clairns 1 to 12, and - cutting through the rail by means of a cutting disc (5) which is driven in rotation by means of the abrasive cutter (1).
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE202019103132.8 | 2019-06-04 | ||
| DE202019103132.8U DE202019103132U1 (en) | 2019-06-04 | 2019-06-04 | Cut-off machine for cutting through a rail of a track |
| PCT/EP2020/062542 WO2020244874A1 (en) | 2019-06-04 | 2020-05-06 | Angle grinder and method for cutting through a rail of a track |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA3141980A1 true CA3141980A1 (en) | 2020-12-10 |
Family
ID=70554094
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA3141980A Pending CA3141980A1 (en) | 2019-06-04 | 2020-05-06 | Abrasive cutter and method for cutting through a rail of a track |
Country Status (9)
| Country | Link |
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| US (1) | US20220032420A1 (en) |
| EP (1) | EP3941682B1 (en) |
| JP (1) | JP2022535864A (en) |
| CN (1) | CN113840690A (en) |
| AU (1) | AU2020286562A1 (en) |
| CA (1) | CA3141980A1 (en) |
| DE (1) | DE202019103132U1 (en) |
| EA (1) | EA202193011A1 (en) |
| WO (1) | WO2020244874A1 (en) |
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|---|---|---|---|---|
| EP4190490A1 (en) * | 2021-12-01 | 2023-06-07 | Hilti Aktiengesellschaft | Machine tool with a specific power to weight ratio |
| DE102022101073A1 (en) | 2022-01-18 | 2023-07-20 | Wacker Neuson Produktion GmbH & Co. KG | material separator |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7059947B2 (en) * | 2004-05-12 | 2006-06-13 | The Stanley Works | Portable rail cutting apparatus |
| JP2013119129A (en) * | 2011-12-06 | 2013-06-17 | Makita Corp | Power tool |
| US9085076B2 (en) * | 2012-02-16 | 2015-07-21 | Nanotek Instruments, Inc. | Surface-mediated cell-driven power tools and methods of operating same |
| CN103537754B (en) * | 2012-07-13 | 2016-10-05 | 苏州宝时得电动工具有限公司 | Portable cutter |
| CN103537753A (en) * | 2012-07-13 | 2014-01-29 | 苏州宝时得电动工具有限公司 | Portable cutting machine |
| DE102013202964A1 (en) * | 2013-02-22 | 2014-09-11 | Robert Bosch Gmbh | Hand tool |
| DE102013210971A1 (en) * | 2013-06-12 | 2014-12-18 | Robert Bosch Gmbh | Electronic unit with a mechanical interface and an electrical interface |
| DE102013215821A1 (en) * | 2013-08-09 | 2015-02-12 | Robert Bosch Gmbh | Hand tool with an electric motor drive as a direct drive |
| CN104772522B (en) * | 2014-01-10 | 2017-10-17 | 苏州宝时得电动工具有限公司 | A kind of hand-held cutting machine |
| JP6408870B2 (en) * | 2014-11-05 | 2018-10-17 | 株式会社マキタ | Electric tool |
| US11338426B2 (en) * | 2015-11-02 | 2022-05-24 | Black & Decker, Inc. | Cordless power cutter |
| EP3173187A1 (en) * | 2015-11-25 | 2017-05-31 | HILTI Aktiengesellschaft | Portable, hand held cutting-off machine |
| DE102016205648A1 (en) * | 2016-04-06 | 2017-10-12 | Robert Bosch Gmbh | Hand tool with three-phase connection and electronically commutated electric motor |
| US10549363B2 (en) * | 2016-06-27 | 2020-02-04 | Mechanical & Electrical Concepts, Inc. | Attachable and extendable saw and methods for using same |
| DE102016122904A1 (en) * | 2016-11-28 | 2018-05-30 | C. & E. Fein Gmbh | Hand tool with overload protection |
-
2019
- 2019-06-04 DE DE202019103132.8U patent/DE202019103132U1/en active Active
-
2020
- 2020-05-06 CN CN202080036061.7A patent/CN113840690A/en active Pending
- 2020-05-06 EP EP20724103.5A patent/EP3941682B1/en active Active
- 2020-05-06 EA EA202193011A patent/EA202193011A1/en unknown
- 2020-05-06 WO PCT/EP2020/062542 patent/WO2020244874A1/en unknown
- 2020-05-06 JP JP2021572266A patent/JP2022535864A/en active Pending
- 2020-05-06 AU AU2020286562A patent/AU2020286562A1/en active Pending
- 2020-05-06 CA CA3141980A patent/CA3141980A1/en active Pending
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|---|---|
| AU2020286562A1 (en) | 2021-12-16 |
| EA202193011A1 (en) | 2022-02-16 |
| US20220032420A1 (en) | 2022-02-03 |
| EP3941682A1 (en) | 2022-01-26 |
| JP2022535864A (en) | 2022-08-10 |
| WO2020244874A1 (en) | 2020-12-10 |
| CN113840690A (en) | 2021-12-24 |
| DE202019103132U1 (en) | 2020-09-07 |
| EP3941682B1 (en) | 2022-04-27 |
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