Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D45/00—Sawing machines or sawing devices with circular saw blades or with friction saw discs
  • B23D45/18—Machines with circular saw blades for sawing stock while the latter is travelling otherwise than in the direction of the cut
  • B23D45/20—Flying sawing machines, the saw carrier of which is reciprocated in a guide and moves with the travelling stock during sawing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D45/00—Sawing machines or sawing devices with circular saw blades or with friction saw discs
  • B23D45/02—Sawing machines or sawing devices with circular saw blades or with friction saw discs with a circular saw blade or the stock mounted on a carriage
  • B23D45/021—Sawing machines or sawing devices with circular saw blades or with friction saw discs with a circular saw blade or the stock mounted on a carriage with the saw blade mounted on a carriage
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D47/00—Sawing machines or sawing devices working with circular saw blades, characterised only by constructional features of particular parts
  • B23D47/08—Sawing machines or sawing devices working with circular saw blades, characterised only by constructional features of particular parts of devices for bringing the circular saw blade to the workpiece or removing same therefrom
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23D—PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR
  • B23D59/00—Accessories specially designed for sawing machines or sawing devices
  • B23D59/001—Measuring or control devices, e.g. for automatic control of work feed pressure on band saw blade
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q15/00—Automatic control or regulation of feed movement, cutting velocity or position of tool or work
  • B23Q15/007—Automatic control or regulation of feed movement, cutting velocity or position of tool or work while the tool acts upon the workpiece
  • B23Q15/12—Adaptive control, i.e. adjusting itself to have a performance which is optimum according to a preassigned criterion
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B19/00—Programme-control systems
  • G05B19/02—Programme-control systems electric
  • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
  • G05B19/404—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B19/00—Programme-control systems
  • G05B19/02—Programme-control systems electric
  • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
  • G05B19/416—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control of velocity, acceleration or deceleration
  • G05B19/4163—Adaptive control of feed or cutting velocity
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q11/00—Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling work; Safety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
  • B23Q11/14—Methods or arrangements for maintaining a constant temperature in parts of machine tools
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/30—Nc systems
  • G05B2219/37—Measurements
  • G05B2219/37428—Temperature of tool
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/30—Nc systems
  • G05B2219/37—Measurements
  • G05B2219/37434—Measuring vibration of machine or workpiece or tool
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/30—Nc systems
  • G05B2219/45—Nc applications
  • G05B2219/45144—Saw
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B2219/00—Program-control systems
  • G05B2219/30—Nc systems
  • G05B2219/49—Nc machine tool, till multiple
  • G05B2219/49206—Compensation temperature, thermal displacement, use measured temperature

Definitions

• the present disclosure relates to a flying saw for cutting extruded profiles with a cutting speed control using the temperature of the cutting edge of the saw blade of the flying saw, a method for controlling a cutting speed of a flying saw for cutting extruded profiles using the temperature of the cutting edge of the saw blade of the flying saw, and an extrusion apparatus for manufacturing extruded profile cuts comprising such a flying saw, all of them especially suitable for cutting extruded plastic or plastic/metal compound profiles for windows, doors and fa- cade elements.
• insulating profile elements like insulating connector strips connecting metal profiles on the weather side and metal profiles on the indoor side of the windows, doors and facade elements or insulating spacer profiles used in insulating glass units (IGUs).
• IGUs insulating glass units
• Such insulating profile elements are usually made from extruded plastic or plastic/metal compound profiles.
• the plastic material may include fiber reinforcement such as glass fibers.
• Another technical field in which corresponding extruded plastic or plastic/metal compound profiles are used is the field of profiles for sliding windows or roofs in automobiles.
• the plastic or plastic/metal compound profiles are produced by extrusion as an endless extrusion profile and then cut into profile cuts, usually of 6 m length.
• the cutting is usually done by a saw, often a flying saw.
• the quality of the cutting in terms of precision and avoiding burrs and the like is important to avoid excessive scrap.
• the quality of the cutting depends, however, on the materials and geometry of the profiles to be cut, on the type of the saw blade and on the rotational speed of the saw blade and on the cutting speed of the saw blade and on the wear of the saw blade, etc. as know in the art.
• the parameters rotational speed and cutting speed of the saw blade are set in view of the materials and geometry of the profiles to be cut, the wear of the saw blade, etc. based on the experience and skill of the operator of the saw. This may lead to unnecessary scrap and low production yields.
• a saw for cutting extruded profiles including a control for controlling the drive power of the drive motor of the saw to be constant described in DE 196 22 374 Al
• a saw for cutting extruded profiles including a control for indirectly controlling the cutting speed of the saw by changing the feed rate described in DE 44 08 886 Al
• a saw including a control for controlling the cutting speed of the saw considering parameters such as saw blade angle, saw position, motor drive current and speed and acceleration signals described in DE 44 05 660 Al
• a saw for a harvester including a control for controlling the sawing speed to be constant described in DE 10 2011 108 814 Al .
• an object of the invention to provide an improved flying saw for cutting extruded profiles, an improved method for controlling a cutting speed of a flying saw for cutting extruded profiles, and an improved extrusion apparatus for manufacturing extruded profile cuts comprising such a flying saw, which are especially suitable for cutting extruded plastic or plastic/metal compound profiles with or without fiber reinforcement for windows, doors and facade elements, sliding windows or roofs in automobiles, and the like. It is also an object to apply the technique to stationary saws for cutting extruded profiles.
• This object is achieved by a flying saw for cutting extruded profiles according to claim 1 , an improved method for controlling a cutting speed of a flying saw for cutting extruded profiles according to claim 8, and an improved extrusion apparatus according to claim 10.
• the additional object is achieved by a stationary saw according to claim 11 and a method for cutting extruded profiles according to claim 12.
• the provision of the temperature detector allows to keep the processing temperature at the cutting edge to be below the glass transition temperature and/or below the melting temperature of the thermoplastic materials of the profile to be cut. These temperatures can be measured or taken from a material data sheet. Thus it is possible to define an acceptable temperature maximum and an intended temperature range for the processing.
• the acceptable temperature maximum and intended temperature range can be stored in the control system and compared it to the continuous measured/detected temperature. The system is quite simple and can be included in the saw control unit.
• This control does not only allow to keep the temperature below the acceptable temperature maximum but also allows to increase the cutting speed if the temperature is low and thus increase the efficiency and to conclude form the detected temperature to the wear of the saw blade as the temperature will be increased for the same cutting speed with increasing wear of the saw blade. If combined with a vibration based control and/or with an optical burr detection, the temperature based control can be improved and potential errors can be avoided more likely.
• Fig. 1 a cross-sectional side view of an exemplary schematic extrusion apparatus in a) and enlarged views of parts of the apparatus in b) and c);
• Fig. 2 a schematic view of a flying saw according to an embodiment
• Fig. 3 a more detailed schematic view of a flying saw according to an embodiment
• FIG. 1 is a cross-sectional side view of an exemplary schematic extrusion apparatus in a) and enlarged views of parts of the apparatus in b) and c).
• the extrusion apparatus shown in Fig. 1 comprises an extruder 1, an extrusion die
• the plastic material is fed into the extruder 1, heated up above its melting temperature and then pressed through the extrusion die.
• the plastic material described further below may but does not have to include reinforcing fiber materials such as glass fibers, carbon fibers, aramid fibers and the like. Of course, the usual fillers, additives, etc. may be included in the plastic material.
• the extrusion die schematically shown in a cross-sectional side view in Fig. la) and b) results in a hollow extrusion profile, but any type of extrusion profiles suitable for the above indicated purposes is possible.
• the extrusion die 2 can be suitable for a co-extrusion or for adding one or more metal sheets or metal wires as known in the art.
• the feeding direction of the plastic material in the extruder 1 and in the extrusion die 2 as well as in the calibration unit 3, 4 is from left to right in Fig. 1.
• a pulling and/or conveying unit 5 is positioned downstream of the calibration unit 3, 4 in the feeding direction.
• the drawing/conveying unit 5 draws the calibrated extrusion profile in the feeding direction to maintain a continuous movement of the extruded profile.
• a flying saw 10, a further drawing/conveying unit 5, a conveying unit 6 and product table 7 are positioned in this order downstream of the first drawing unit 5 in the feeding direction, as shown in Fig. la) and lc).
• the flying saw 10 is moveable back and forth parallel to the feeding direction in order to cut the moving extrusion profile P into pieces or profile cuts CP of a predetermined length.
• the flying saw 10 comprises a saw blade which can be moved perpendicular to the feeding direction as schematically shown in Fig. la) and c).
• the profile cuts CP are singled and transported in the feeding direction and finally laid on to the product table 7.
• Fig. 4a) to d) show cross-sectional views perpendicular to the longitudinal direction of four exemplary profiles to be cut.
• a profile is formed, for example, from a thermoplastic polymer selected from the group consisting of polyethylene terephthalates, polyurethanes, poly- imides, polyetherimides, polytetrafluoroethylenes, polyvinylchlorides, polyamides, polycarbonates, epoxy resins, polymethylmethacrylates, polystyrenes, polysiloxanes, polyphenylene oxides, polyketones, polyetheretherketones, biopolymers, and mixtures thereof, or a mixture thereof with one or more polyolefm(s), and/or a thermoplastic polymer is selected from the group consisting of PA66, PA6, PA/PPO, SPS, and the biopolymers PA4.10, PA5.5, PA5.10, PA6.10, PA10.10, PA11 and PA10.12, and mixtures thereof, or a mixture thereof with one or more thermo
• the profile is manufactured by extrusion. As already described above, usual fillers and additives and reinforcing materials such as glass fibers can be added. Furthermore, depending on the application of the profile, the extruded profile may be a plastic/metal com- pound profile. For example, if the extruded profile is designated to be a spacer for IGUs, it is common to coextrude a thin metal layer of stainless steel or coated steel with the plastic material to cover at least one side of the profile or to laminate or deposit the thin metal layer thereon. The cross-section perpendicular to the longitudinal direction of such a spacer profile is shown in Fig. 4d).
• Fig. 4a) and b) are designed to connect metal profiles of windows, doors and facade elements. It is obvious, that they can have cross-sectional shapes of a rather simple design as shown in Fig. 4a) or of a more sophisticated design with many arms or branches, which are more difficult to cut. The same applies to a profile such as the one shown in Fig. 4c), which, in the cross-section perpendicular to its longitudinal direction, has hollow spaces, partly open spaces and protruding arms.
• these profiles may include corresponding reinforcements or metal or other coatings as described with respect to Fig. 4d). Moreover, it may be necessary to cut the plastic or plastic/metal compound profiles shown in Fig. 4 together with other attached profiles such as the metal profiles of windows, doors and facade elements.
• the quality of the cross-sectional face cut by the flying saw is of great importance. If the quality is not good enough, the corresponding profile cut is a scrap.
• the quality of this cut de- pends on many parameters such as the saw blade design, the saw blade angle, the saw blade wear, the rotational speed of the saw blade, the speed of moving the saw blade perpendicular to the longitudinal direction of the profile, the temperature of the profile, the temperature of the surrounding space such as the room temperature, the type(s) of the material(s) and the combination of material(s) as well as the cross-sectional shape of the profile.
• the temperature at the cutting edge of the saw may be too high for the plastic material of the profile.
• the temperature at the cutting edge of the saw blade is at or above the glass transition temperature and/or the melting temperature of the plastic materials of the profile to be cut, an acceptable quality of the cut face cannot be obtained.
• the temperature of the cutting edge may be significantly higher than without such metal inserts, even if the other materials and the design of the profile are the same otherwise.
• FIG. 2 shows a schematic view of a flying saw according to an embodiment
• Fig. 3 shows a more detailed schematic view of a flying saw according to an embodiment.
• the saw unit 10 comprises a temperature sensor 12.
• This temperature sensor may be, for example, an infrared temperature sensor detecting the temperature of the cutting edge of the saw blade 11 based on the infrared radiation of the same.
• it is also possible to use other technologies such as a temperature-dependent metal coating changing its resistance based on its temperature. In such a case, eddy currents in the rotating saw blade that change with the temperature could be measured.
• an infrared temperature sensor is considered to be the easiest way to implement the temperature detection in the present case.
• the feeding direction is represented by the arrow F.
• the movement of the flying saw and its saw blade 11 back and forth parallel to the feeding direction F is represented by the arrow FS H.
• a movement perpendicular to the longitudinal direction of the profile which corresponds to the feeding direction F, is represented by the arrow FS L.
• the rotational speed is represented by the arrow SR.
• the temperature sensor 12 is connected to the control system 13, which controls the rotational speed SR and the movement FS L perpendicular to the longitudinal direction of the profile P depending on the detected temperature.
• the rotational speed SR and the movement of the saw blade perpendicular to the longitudinal direction of the profile P combine to a cutting speed.
• the cutting speed can be changed by changing the rotational speed SR of the saw blade 11 and/or by changing speed of the movement of the saw blade 11 perpendicular to the longitudinal direction of the profile P.
• the movement of the saw blade 11 perpendicular to the longitudinal direction of the profile P can be of course in movement in the lateral direction only, as indicated by the arrow FS L in Fig. 2, or can be a movement in a vertical direction FS V only or a combination of the same.
• Fig. 3 shows a more detailed schematic drawing of an embodiment of a flying saw.
• the flying saw 10 comprises the saw blade 11 driven for rotation by a first saw blade drive 17, which usually includes an electric motor for rotating the saw blade 11.
• the flying saw 10 further comprises a support 14 for the circular saw.
• the saw carriage 16 allows to move the circular saw 11, 17 in the lateral horizontal direction FS L and/or in the vertical direction FS V as indicated by the arrows in Fig. 3.
• the saw carriage 16 is moveable back and forth in the first direction FS V by the linear mov- ing unit 15 as also indicated by the arrows in Fig. 3.
• the moveable workpiece support 18 is posi- tioned below the profile to be cut to support the profile during the cutting operation.
• the work- piece support 18 is also moveable back and forth in the first direction FS V.
• the control system 13 is connected to the drives of the drawing/conveying units 5 via signal lines 19, 21 and is connected to the drive of the conveying unit 6 via signal line 22.
• the control system 13 is connected to the support 14, the saw blade drive unit 17, the saw car- riage 16, the linear moving unit 15, the workpiece support 18 and the temperature sensor 12 via signal line 20.
• the control system 13 can control the speeds of movement of the profile P to be cut and of the profile cuts CP after the profile has been cut as well as the rotational speed of the saw blade 11 and the speed of movement of the saw blade 11 in the three directions FS H, FS L and FS V as well as the corresponding movement speed in the direction FS H of the workpiece support 18.
• the control system 13 can obtain the result of the IR measurement of the temperature of the cutting edge of the saw blade 11 via signal line 20.
• the control system 13 is enabled to move the saw blade 11 and the work- piece support 18 in synchronization with the movement of the profile P to be cut and, at the same time, to control the cutting speed resulting from rotational speed SR of the saw blade 11 and of the speed of movement of the saw blade 11 perpendicular to the longitudinal direction of the profile P using the temperature detected by the temperature sensor 12.
• the control scheme is described further below. It is obvious from Fig. 3, that the conveying speed of the drawing/conveying unit downstream of the saw blade 11 in the feeding direction F is higher than the conveying speed upstream of the saw blade in order to single the profile cuts CP.
• the conveying speed of the conveying unit 6 is at least equal to this higher conveying speed of the second drawing/conveying unit 5 in order to maintain the singling and to be able to properly lay the profile cuts CP on the product table 7. It is obvious that these conveying speeds are controlled by the control system 13 via signal lines 19, 21 and 22.
• the flying saw 10 may optionally include a vibration detection de- vice 23 for detecting vibrations of the saw blade and/or of the profile P to be cut.
• the vibration detection is made in the usual way by detecting the vibrations acoustically and/or optically.
• the vibration detection device 23 is connected to the control system 13 via signal line 24.
• the flying saw 10 optionally includes an optical detection device for detecting burrs at the cut face of the extruded profile after it has been cut and/or of the profile cuts CP.
• This optical detection device 25 is connected to the control system 13 via signal line 26.
• the control scheme for the operation of the flying saw 10 can consider the above described cutting parameters in the usual way.
• the control scheme uses the detected temperature of the cutting edge of the saw blade 11 to prevent to exceed a maximum temperature for cutting the material and optionally to optimize the cutting speed based on the detected tem- perature. As already described above, depending on the material of the profile and/or depending on the design of the profile, a specific cutting speed will result in a corresponding temperature of the cutting edge of the saw blade 11.
• the flying saw is controlled to be keep the temperature of the cutting edge of the saw blade within a predetermined temperature range.
• the upper limit of the temperature range is determined by the glass transition temperature and/or the melting temperature of the plastic material of the profile to be cut minus a certain offset value of, for example 5K, 10K, 15K, 20K, 25K, 30K, 35K, 40K, 45K, 50K.
• a certain offset value for example 5K, 10K, 15K, 20K, 25K, 30K, 35K, 40K, 45K, 50K.
• a certain offset value of, for example 5K, 10K, 15K, 20K, 25K, 30K, 35K, 40K, 45K, 50K.
• For usual thermoplastic materials that preferable offset is at least 10K. The offset does not need to be bigger than 50K under normal circumstanc- es.
• the lower limit of the temperature range is usually set to be 10K, 15K, 20K, 25K,
• the control can increase or decrease the rotational speed of the saw blade 11 and/or the speed of movement of the saw blade 11 perpendicular to the longitudinal direction of the profile P in order to control the cutting speed and the quality of the cut face of the profile P to be cut and of the profile cuts CP.
• HM and HSS saw blades with different teethings can be used, where the saw blade diameter is usually in the range between 250 and 350 mm, preferably 300 mm, and the rotational speed of the saw blade is usually set in a range between 1000 and 1500 rpm.
• the moving speed of the profiles to be cut is in the range of 4 to 12 m/min.
• the technique and control of the temperature can also be used for stationary saws and not only for flying saws. In such a case, the plural profiles can be cut simultaneously.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Human Computer Interaction (AREA)
• Manufacturing & Machinery (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Automation & Control Theory (AREA)
• Sawing (AREA)

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• 2017
  • 2017-06-02 EP EP17733980.1A patent/EP3624975A1/en not_active Withdrawn
  • 2017-06-02 CN CN201780091494.0A patent/CN110785251A/zh active Pending
  • 2017-06-02 WO PCT/EP2017/063570 patent/WO2018219477A1/en unknown

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