EP3781352A1 - Feinbearbeitungsverfahren zum herstellen einer nicht-kreiszylindrischen bohrung sowie feinbearbeitungssystem und schleifwerkzeugeinheit - Google Patents
Feinbearbeitungsverfahren zum herstellen einer nicht-kreiszylindrischen bohrung sowie feinbearbeitungssystem und schleifwerkzeugeinheitInfo
- Publication number
- EP3781352A1 EP3781352A1 EP19717836.1A EP19717836A EP3781352A1 EP 3781352 A1 EP3781352 A1 EP 3781352A1 EP 19717836 A EP19717836 A EP 19717836A EP 3781352 A1 EP3781352 A1 EP 3781352A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- grinding
- grinding tool
- bore
- tool
- main spindle
- Prior art date
- 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
Links
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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
- B24B5/00—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
- B24B5/36—Single-purpose machines or devices
- B24B5/40—Single-purpose machines or devices for grinding tubes internally
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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
- B24B33/00—Honing machines or devices; Accessories therefor
- B24B33/02—Honing machines or devices; Accessories therefor designed for working internal surfaces of revolution, e.g. of cylindrical or conical shapes
-
- 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
- B24B33/00—Honing machines or devices; Accessories therefor
- B24B33/08—Honing tools
- B24B33/088—Honing tools for holes having a shape other than cylindrical
-
- 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
- B24B33/00—Honing machines or devices; Accessories therefor
- B24B33/10—Accessories
- B24B33/105—Honing spindles; Devices for expanding the honing elements
-
- 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
- B24B41/04—Headstocks; Working-spindles; Features relating thereto
-
- 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
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/10—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces
- B24B47/12—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces by mechanical gearing or electric power
Definitions
- the invention relates to a fine machining method for producing a non-circular-cylindrical bore, which has at least one non-circular-cylindrical bore section with a non-circular bore cross-section and / or an axial contour, as well as a fine machining system suitable for carrying out the finishing process and a grinding tool unit which can be used.
- cylinder surfaces in cylinder blocks (cylinder crankcases) or cylinder liners of internal combustion engines or other reciprocating engines are exposed during operation of a strong tribological stress. Therefore, it is important in the production of cylinder blocks or cylinder liners to edit these cylinder surfaces so that later in all operating conditions sufficient lubrication is ensured by a lubricant film and the frictional resistance between relatively moving parts is minimized.
- Honing is a machining process with geometrically indeterminate cutting edges.
- an expandable honing tool is reciprocated within the bore to be machined to produce a stroke in the axial direction of the bore with a stroke frequency and simultaneously rotated to produce a rotational movement superimposed on the stroke with a presettable rotational speed.
- Schneidstoff entrepreneurial be delivered via a feed system radially to the axis of rotation of the honing tool.
- a cross-cut pattern typical for honing is usually produced on the inner surface with intersecting machining marks, which are also referred to as "honing marks".
- the optimization of the tribological system piston / piston rings / cylinder surface is of particular importance in order to achieve low friction, low wear and low oil consumption.
- the macroscopic shape (macro-shape) of the holes and the surface structure is of particular importance.
- a cylinder bore in the operation of the engine should have a bore shape that deviates as little as possible from an ideal circular cylinder shape, so that the piston ring package can seal well over the entire bore circumference.
- the sealing function of the piston ring assembly and piston friction are typically degraded by such hard-to-control deformations, which can increase blow-by, oil consumption, and friction.
- the fine machining method has in common that they can produce a non-circular cylindrical bore shape, starting from an approximately circular-cylindrical starting shape of the bore by locally uneven machining material removal having at least one non-circular cylindrical bore portion with a non-circular bore cross-section and / or an axial contour.
- EP 1 321 229 A1 describes methods for producing a bore, in particular the cylinder bore of a reciprocating piston engine, the bore having an initial shape in the unloaded state and, in the operating state, a desired shape deviating from the starting shape. It is mentioned that the initial form basically by procedures with defined cutting edge, grinding, spark erosion or honing. A honing process will be explained in more detail.
- GB 2 310 704 A discloses a finishing method in which the bore is first brought from a starting shape by a numerically controlled Bohroperation with geometrically defined cutting edge in a non-circular cylindrical bore shape and then the inner surface of the bore is finished by at least one honing operation to To give the bore surface the desired surface structure.
- DE 10 2014 225 164 A1 describes a fine machining method in which the bore is first brought from a starting shape by a grinding operation in a non-circular cylindrical, rotationally symmetrical shape and then the inner surface of the bore is finished by means of at least one honing operation.
- an expandable honing tool is used, which has at least one with respect to their effective diameter expandable annular cutting group with a plurality of circumferentially distributed around the circumference of the tool body, axially relatively short cutting material bodies.
- a contour generation phase a non-circular-cylindrical rotationally symmetrical bore section having a predeterminable axial contour profile is produced by generating an uneven material removal in the axial direction of the bore on the inner surface of the bore.
- the honing tool is for this purpose coupled to the work spindle or main spindle of a machine tool. There is a fast turning of the honing tool in combination with a slow axial movement of the honing tool. In this case, during the axial movement of the honing tool, a path-controlled radial infeed of the cutting material body takes place with a delivery position dependent on the axial position.
- a special feature of this method is that on the one hand a honing tool is used, that is, a tool which is basically suitable for honing operations and works with geometrically indeterminate cutting.
- the honing tool is operated at very high speeds in comparison with conventional honing and in comparison to conventional low-speed honing, so that the resulting material removal process resembles a grinding or grinding operation.
- the fine machining process is used to produce a non-circular cylindrical bore.
- This is understood here to mean a bore which has at least one noncircular cylindrical bore section which has a non-circular bore cross section and / or an axial contour profile.
- a "non-round bore cross-section" is given when the cross-sectional shape of the bore in the bore portion deviates significantly from a circular shape.
- the cross section may e.g. be oval, have a cloverleaf or even a non-symmetrical shape deviation, possibly with higher order.
- there may be a uniform or irregular waviness in the circumferential direction (azimuthal direction).
- An "axial contour” is e.g. then given when the cross-sectional shape and / or the cross-sectional size of the bore varies in the axial direction.
- a conically shaped rotationally symmetrical bore section has an axial contour profile in which the bore diameter in the case of a continuous circular cross-sectional shape increases or decreases continuously in the axial direction.
- a deviation from the circular cylindrical shape can only consist in that, in the case of a continuous circular cross-sectional shape, an axial contour profile is provided.
- an axial contour profile is provided.
- a rotationally symmetrical bore with barrel shape, bottle shape or cone shape or a bore with a circular cylindrical portion and an adjoining conical portion can be generated.
- the cross-sectional shape changes in the axial direction of the bore, there is additionally an axial contour.
- the bore may have a non-circular cylindrical shape over its entire length. It is also possible that, in addition to the (at least one) non-circular-cylindrical bore section, at least one circular-cylindrical bore section is provided or generated.
- the fine machining process is performed by using a machine tool having a main spindle (work spindle, machine tool spindle) which is rotatable about a main spindle axis by means of a first drive and slidable by a second drive parallel to the main spindle axis (ie, in the axial direction).
- the working movements of the main spindle can be controlled by signals of a control unit of the machine tool, so that e.g. the axial position, the angular position and the speed of the main spindle and their mutual dependencies as a function of time or the machine cycle can be precisely specified by a control program.
- the bore is brought from an initial shape by a grinding operation with axially and / or azimuthally uneven material removal in a non-circular cylindrical bore shape. Since the grinding operation due to the axial and / or circumferentially uneven material removal can make a significant contribution to the shaping of the bore and by grinding a significant change in the initial shape is brought about, this step in this application is also referred to as "form grinding operation" or "shape grinding”.
- the inner surface of the bore ground thereby is finished by means of at least one further machining operation.
- This finishing makes it possible to obtain a surface structure on the finished bore which differs from a surface structure obtainable by grinding.
- the further machining operation may, in particular, be a honing operation, with which, for example, while largely eliminating the surface structure produced by grinding, but largely retaining the surface Macroform, the desired surface structure of the bore, eg with crossed honing marks, is produced on the end product.
- the initial shape may be, for example, circular cylindrical, but this is not mandatory. It is also possible to drill the hole prior to the start of the grinding operation by a corresponding pre-processing, e.g. by another grinding operation or by a fine boring operation, to bring into a non-circular cylindrical initial shape, e.g. a rotationally symmetric initial shape with axial contour.
- the starting shape may be a barrel-shaped, bottle-shaped or cone-shaped or a shape having a circular-cylindrical section and at least one adjoining conical section.
- This non-circular cylindrical starting shape may then be further modified by the form grinding operation, e.g. by generating an azimuthal waviness at the already non-circular-cylindrical initial shape. This can produce a bore shape with significant deviations from rotational symmetry.
- a grinding tool unit which can be coupled to the work spindle and which has a main body that can be rotated about a main body axis is used to carry out the grinding operation.
- the main body carries at least one grinding spindle unit with a grinding tool attached thereto, which can be driven to rotate about a grinding tool axis by means of a grinding tool drive.
- the grinding tool drive is a drive belonging to the grinding tool unit, which is present in addition to the first drive of the machine tool and during grinding operation (during the grinding operation) can cause a rotation of the grinding tool regardless of a possible rotation of the main spindle.
- the grinding tool has an abrasive body with an abrasive peripheral surface.
- the diameter of the abrasive body is smaller than the bore diameter in such a way that engagement between the bore inner wall and the abrasive body takes place only in a narrow engagement area on the circumference of the abrasive body.
- the grinding tool unit is coupled to the main spindle. Then, by generating working motions of the grinding tool on the bore inner surface, a grinding operation with axially and / or azimuthally uneven material removal (shaping grinding operation) is performed.
- the grinding tool is rotated via the grinding tool drive with a predeterminable (constant or temporally varying) rotational speed in order to be able to produce the desired removal of material at the bore inner surface.
- An abrasive peripheral surface of the grinding wheel of the grinding tool is by one-sided delivery of the Grinding tool in the direction of the bore inner surface locally brought into engagement with the bore inner surface.
- the extent of material removal in the local engagement region between the grinding body and the bore inner surface is determined by a variation of the delivery of the grinding tool and / or by a variation of the rotational speed of the grinding body and / or by a variation of the contact time controlled between the grinding wheel and the bore inner surface.
- the essential portion of the cutting speed between the grinding body and the bore inner surface required for material removal is achieved by a correspondingly high speed of the grinding tool.
- This is generated by means of the grinding tool drive, regardless of a possible rotation of the main spindle.
- the controlled over the signals of the control unit of the machine tool working movements of the main spindle are mainly or exclusively for guiding the grinding tool within the bore, in particular for specifying the axial position and the angular position of the grinding tool and thus to specify the position of the engagement region between the circumference of the grinding body and bore inner surface in Course of the grinding operation.
- the main spindle and the abrasive body can rotate in the same direction or in opposite directions, whereby an opposite rotation can contribute to increasing the effective cutting speed.
- the grinding tool or its grinding body can reach the complete inner surface of the bore section to be brought into a non-circular cylindrical shape in the course of the grinding operation, so that more or more of the entire inner surface of this bore section can be obtained by grinding less material can be removed.
- the local contact time between the grinding body and the bore inner surface can be predetermined in a targeted manner as a function of the axial position and the angular position of the engagement region via the activation of the first and the second drive.
- these Both drives can be used to control the feed rate of the grinding tool along the intended path on the bore inner surface.
- the grinding operation can be regarded as a way of internal grinding by means of peripheral grinding, but differs from classic internal cylindrical grinding in that the working movements of the grinding tool are controlled such that the hole-shaped bore shape deviates significantly from a circular-cylindrical bore shape.
- a variable control of the delivery of the grinding tool takes place as a function of the axial position and the angular position of the grinding tool. If the feed position of the grinding tool is changed during a movement along the path predetermined by the main spindle, the grinding tool can be targeted more or less strongly engaged with the bore inner wall and remove material there.
- the feed direction preferably corresponds substantially to the local normal direction to the bore inner surface, but may also run obliquely thereto if at least one component of the feed is oriented perpendicular to the bore surface.
- the delivery is one of those internal forces or intervention variables that can be specified very precisely by means of control commands of the control unit of the machine tool.
- a variable control of the infeed By means of a variable control of the infeed, a specific deviation from a circular bore shape can be generated precisely even at a constant rotational speed of the grinding tool and / or constant rotational speed and axial velocity of the main spindle.
- the infeed may be controlled to vary during one revolution of the main spindle in accordance with a predetermined function with at least one increase in the infeed position and at least one decrease in the infeed position.
- a non-round cross-sectional shape can be generated selectively.
- Depending on the number of increases and decreases in the delivery position and higher-order form deviations in the circumferential direction can be generated with high precision in any desired axial position.
- the feed position of the grinding tool is changed by radial displacement of the grinding spindle unit relative to the main body axis of the grinding tool unit.
- an in-tool delivery takes place.
- a feed position of the grinding tool is changed by radial displacement of the main spindle relative to its normal position.
- abrasive tool units can be used, which do not allow tool-internal delivery.
- a machine tool with a magnetically mounted main spindle can be used. These are understood here as machine tools whose main spindle is magnetically mounted in a magnetic bearing device.
- an advantage of the magnetic bearing can be exploited, namely a certain controllable mobility of the rotatable main spindle within the bearing air gap.
- the magnetic bearing device can thus be mounted fixed to the machine and the main spindle is magnetically displaceable relative to the magnetic bearing device.
- the first drive it is possible to use the first drive to set the main spindle about its main spindle axis in a self-rotation and at the same time to shift the position of the main spindle axis via electrical control of electromagnets in directions perpendicular to the main spindle axis.
- the feed position of the grinding tool is changed by radial displacement of the grinding tool carrying the rotatable grinding spindle relative to its bearing means.
- a grinding spindle unit with a magnetically mounted grinding spindle can be used, so that it is possible to change the axial position of the rotating part relative to the non-rotating part by means of electrical control.
- a variable control of the rotational speed of the grinding tool is carried out as a function of the axial position and the angular position of the grinding tool.
- the speeds may be, for example, in the range of 600 min 1 to 10,000 min 1 or above. Increasing the speed usually results in a higher material removal per unit of time due to a correspondingly higher cutting speed. As a result of a variation of the rotational speed, a locally varying removal of material can thus be generated even with a constant infeed position.
- the speed can be controlled, for example, such that the speed during a revolution of the main spindle according to a predetermined speed function varies with at least one increase in speed and at least one decrease in speed.
- the pressure forces of the grinding tool on the bore inner surface can result in this variant, for the most part from elasticity within the finishing system, which then relax when the rotating grinding tool removes material.
- machining tool units or finishing systems can be used which offer no possibility of varying the infeed of the grinding tool.
- a variable control of the rotational speed for example in the range of a maximum of 10 ⁇ m.
- this can be sufficient in many cases, for example in the form of grinding of cylinder surfaces.
- a variable control of the delivery of the grinding tool can be combined or superimposed with a variable control of the rotational speed of the grinding tool. It is also possible to vary one of the influencing variables (for example the infeed) while keeping the other influencing variable (for example the rotational speed) constant.
- the grinding tool unit is rigidly coupled to the main spindle.
- the main body axis is permanently coaxial with the main spindle axis.
- a rigid coupling is not mandatory.
- at least one joint may be present between the main body of the grinding tool unit and the main spindle, which may be integrated into the grinding tool unit, for example.
- separate guide means for guiding the axial movement of the grinding tool unit within the bore may be favorable, for example an upper guide and / or a lower guide outside the workpiece.
- an internal guide of the grinding tool unit in the bore there are embodiments of grinding tool units that have an expandable guide group with a plurality of guide rails distributed around the circumference of the body, partially or completely between the grinding tool and a spindle-side coupling structure of the grinding tool unit and / or arranged between the grinding tool and a distal end of the spindle body and can be delivered radially by means of a guide group feed system independently of the grinding tool.
- the bore inner surface After completion of the grinding operation (shaping grinding operation), the bore inner surface usually has a typical abrasive structure, which is characterized, inter alia, by grinding grooves which extend more or less in the circumferential direction of the bore inner wall. Such a structure may be favorable for some applications, so that no further machining operation is necessary and the grinding operation generates the intended surface structure. In such cases, another machining operation can be omitted. This is considered a particular aspect of the present disclosure. A form grinding operation without subsequent further processing operation is thus also the subject of this disclosure.
- the inner surface of the bore is finished by means of at least one further machining operation.
- This finishing can be done by honing.
- the grinding operation typically includes at least one honing operation.
- the grinding tool unit is decoupled from the main spindle, a honing tool is coupled to the main spindle, and at least one honing operation is performed on the bore inner surface by means of the honing tool.
- a grinding tool unit may be used which has a separately deliverable cutting group for honing. This is then brought into working engagement with the bore inner surface instead of the abrasive body.
- the grinding tool unit can be constructed to the same extent as a honing tool with double widening.
- the cutting group for honing may e.g. be arranged in the spindle facing away end of this tool unit, so that the grinding body is closer to the coupling point between this and the cutting group for honing.
- a caster honing operation is desired to create a bore surface desired on the bore interior surface Surface structure performed essentially without changing the macro-shape of the hole.
- "after-honing honing" specially designed honing tools can be used which have only weakly abrasive and / or elastically yielding and / or resilient cutting material bodies which substantially follow a contour of the bore previously created by grinding and are primarily coarser and possibly eliminate finer grinding marks and improve the surface structure without significantly changing the macro-shape.
- a follow-up honing operation for example, a cross-cut structure of suitable roughness and suitable honing angle can be produced.
- the grinding operation can be controlled according to a preset (open loop control) to obtain the desired non-circular cylindrical bore shape.
- the grinding operation is controlled in response to shape measurement signals obtained by measuring the bore, particularly diameter measurement signals.
- shape measurement signals obtained by measuring the bore, particularly diameter measurement signals.
- the desired hole shape can be achieved with higher dimensional accuracy.
- the easiest way to realize the measurement-assisted shape grinding operation is by using a post-measurement station which measures a finished bore to selectively modify (if the shape deviates too much) based on the measurement results the machining parameters for machining the following holes.
- a post-measuring station e.g. can be equipped with an air gauge or with tactile sensors, e.g. then sufficient if the initial form, e.g.
- the grinding tool unit may for this purpose comprise one or more integrated sensors of a shape measuring system, e.g. Air measuring nozzles, which can be radially aligned. Sensors can e.g. in the amount of the grinding wheel, but possibly also be arranged above and / or below.
- the generally relatively slow movement of the main spindle allows accurate measurement even with relatively sluggish measuring systems.
- the invention also relates to a grinding tool unit that can be used in the context of the finishing process, but possibly also in other finishing processes.
- the grinding tool unit has a main body, which can be coupled by means of a coupling device to a main spindle of a machine tool and rotatable by working movements of the main spindle about a main body axis and is movable parallel to the main body axis.
- the grinding tool unit has (at least) a grinding spindle unit carried by the base body for supporting a grinding tool having an abrasive body with an abrasive peripheral surface and rotatably driven about a grinding tool axis by a grinding tool driver.
- the grinding tool drive is integrated in the grinding tool unit.
- the grinding tool unit thus represents a self-contained tool unit, which includes a self-propelled to rotate the grinding wheel.
- On an external drive e.g. via a gear on the grinding tool acts and this drives, can be dispensed with.
- the main spindle to which the grinding tool unit is coupled serves primarily to guide the grinding tool unit to selectively engage the abrasive peripheral surface of the grinding wheel at predetermined positions with the inner surface of a bore to be machined.
- the grinding tool drive has an electric motor.
- the grinding spindle unit may be designed in the manner of an electrically operated motor spindle of suitable size, in which the stator of the motor spindle is mounted on the main body or on a component of the grinding tool unit carried by the main body and the rotor of the grinding spindle unit, e.g. a rotatable shaft that carries abrasive wheels.
- an electric motor as a grinding tool drive particularly good control options are given in terms of the speed of the grinding wheel.
- the grinding tool unit can have a fluid channel system for supplying cooling lubricant into the grinding tool unit, and for the grinding tool drive to have a turbine for converting the flow energy of the cooling lubricant into a rotary movement of the grinding tool.
- a hydraulic drive can for example be used where the machine tool is already equipped with facilities for internal coolant supply to a coupled tool.
- a pneumatic drive for the grinding tool can be provided.
- the grinding spindle unit is fixedly mounted on the base body, so that it can not be displaced relative to the base body.
- abrasive tool units can be used, for example, when the Machine tool has a main spindle, which can be moved vertically controlled to the main spindle axis, such as a magnetically mounted spindle.
- Abrasive tool units which are distinguished by the fact that they have a feed element, which is movable relative to the main body, of a feed device for feeding the grinding tool in the direction of the bore inner surface can be used more universally.
- the feed device can be designed in such a way that the grinding tool or the grinding spindle unit carried by the main body is controlled in the coupled state of the grinding tool unit, e.g. can be displaced in the radial direction to the body axis.
- the radial distance between the provided for engaging the bore inner wall peripheral portion of the grinding body and the body axis preferably be adjusted continuously.
- the effective radius of the grinding tool unit can thus be changed depending on location by external control via the feed device during a grinding operation according to a specification, in particular in dependence on the axial position and the angular position of the main spindle or of the main body coupled thereto.
- the feed device has an electrically controllable actuator integrated in the grinding tool unit for displacing the grinding spindle unit.
- the actuator may, for example, be an electric motor or a piezoelectrically operating actuator.
- a single actuator may suffice, but it is also possible to provide a plurality of actuators that can be controlled in a coordinated manner.
- the feed device has a feed cone, which is arranged so as to be axially displaceable in a guide opening extending parallel to the main body axis and effects radial feed of the grinding spindle unit via cooperating wedge surfaces when the feed cone is axially displaced.
- Such grinding tool units can be used particularly advantageously with machine tools in the form of honing machines, since these typically have a precisely controllable feed system, which has an axially displaceable feed element within the main spindle, which interacts with a tool-axially displaceable feed element when the tool is coupled. In this case, can be dispensed with separate actuators within the grinding tool unit.
- the abrasive body of the grinding tool is preferably designed so that it at least in the region of the abrasive peripheral surface cutting material grains of cubic boron nitride (CBN) or Having diamond in a ceramic or metallic bond.
- CBN cubic boron nitride
- Such abrasive bodies are distinguished from other types of abrasive bodies, inter alia, by very low wear, so that a subsequent compensation of the delivery is not required or only in relatively large time intervals. In this way, on the one hand, the geometric precision in the production of non-circular bore shapes can be increased, on the other hand, the non-productive times for tool changes can be kept short overall, whereby a highly productive finishing process is possible.
- the invention also relates to a fine machining system for producing a non-circular-cylindrical bore, which has at least one non-circular-cylindrical bore section with a non-circular bore cross-section and / or an axial contour.
- the fine machining system comprises a machine tool which can be controlled by signals from a control unit and which has a main spindle which is rotatable about a main spindle axis by means of a first drive and displaceable parallel to the main spindle axis by means of a second drive.
- the finishing system further comprises at least one grinding tool unit of the type described in this application.
- the finishing system further comprises at least one honing tool.
- an automatic tool changing system for selectively coupling a honing tool or a grinding tool unit to the main spindle.
- the machine tool includes a feed system for controllably displacing the main spindle in directions perpendicular to the main spindle axis.
- a delivery of the grinding tool in the direction of the bore inner wall by radial movements of the main spindle can be effected.
- simpler grinding tool units without internal feed elements can be used to change the feed position of the grinding spindle unit.
- the main spindle of the machine tool is magnetically supported in a magnetic bearing device.
- the magnetic bearing device can be mounted fixed to the machine and the main spindle relative to the magnetic bearing device to be magnetically displaceable. Possible uses of the concept have already been described above. BRIEF DESCRIPTION OF THE DRAWINGS
- FIG. 1 shows a schematic longitudinal section through an embodiment of a non-circular cylindrical bore, which has a superposition of a non-circular bore cross-section with an axial contour;
- Fig. 2 shows in Fig. 2A to Fig. 2C, the cross-sectional shapes of the holes in the planes I, II and III in Fig. 1;
- FIG. 3 schematically shows components of a finishing system according to an embodiment with a grinding tool unit coupled to the main spindle;
- FIG. 4 is a schematic view of a plane of the bore perpendicular to the bore axis between the bore entry and the bore exit when a non-circular bore cross-section is created by grinding;
- Fig. 5 shows another embodiment of a grinding tool unit which is rigidly coupled to the free end of a main spindle
- Fig. 6 shows another embodiment of a grinding tool unit which can be rigidly coupled to a main spindle
- Fig. 7 shows schematically an embodiment of a grinding tool unit, which has an expandable guide group with a plurality of distributed around the circumference of the body guide rails;
- Fig. 8 shows a grinding tool unit with a grinding spindle unit, which is mounted in a fixed position in the tool.
- the finishing processes include a grinding operation, also referred to herein as a "grinding operation,” that is configured to produce uneven material removal in the axial and / or circumferential directions of the bore.
- a grinding operation also referred to herein as a "grinding operation”
- This can be achieved, in particular, by one or more of the following measures: (i) By an individual modulation (infeed) of a rotating grinding body (eg perpendicular to the bore axis) as a function of the radial position (angular position) and the axial (bore height) ( ii) By varying the speed of the grinding wheel and thus the material removal rate (iii) By varying the residence time (contact time) at the respective location, eg by different peripheral speed of the main spindle.
- Fig. 1 shows a schematic longitudinal section through an embodiment of such a bore 1 10 in a workpiece 100 in the form of an engine block (cylinder crankcase) for an internal combustion engine.
- the bore has a bore axis 112 and extends in the axial direction over a bore length of a in the installed state the cylinder head facing bore entrance 114 to the bore exit 16 at the opposite end.
- Fig. 1 shows with dashed lines an initial shape AF of the bore before the start of the fine machining operations described herein.
- the initial shape results from previous processing stages (e.g., by fine boring and / or grinding) and, in the example, is in the form of a circular cylinder centered on the bore axis 112.
- Solid lines show the desired shape SF of the hole after completion of the fine machining.
- the desired target form SF shown here by way of example can be subdivided into a plurality of mutually adjoining sections, which, as seen in the axial direction, merge into one another continuously or without the formation of steps, edges or jumps.
- FIGS. 2A, 2B and 2C show schematic cross-sectional representations of the bore cross-section in the planes I, II and III marked in FIG. 1.
- the bore has a non-circular bore cross-section, ie a cross-sectional shape that deviates significantly from a circular shape.
- the bore cross-section is approximately cloverleaf-shaped with four in about 90 ° to each other standing radial bulges, between which in the circumferential direction each sections lie with a local minimum of the bore radius or the bore diameter.
- the bore cross-sectional shape can also be described as a four-fold azimuthal waviness. The radial deviations from an ideal circular shape are exaggerated, on the real workpiece, for example, they can be in the order of a few tens of micrometers.
- the cross-sectional shape is increasingly approaching a circular shape.
- the illustrated plane II lies within a second bore section BA2, also referred to herein as a transition section, which marks the transition between the first bore section BA1 (with more or less constant mean bore diameter in the axial direction) and a third bore section BA3 in which the mean diameter the bore increases continuously in the direction of the bore exit.
- the desired shape SF is more or less conical, so that, for example, in the plane III near the bore exit there is a circular cross-sectional shape (FIG. 2C) whose diameter is greater than in the plane II.
- the desired shape of the total non-circular cylindrical bore is therefore characterized in the vicinity of the bore inlet 114 mainly by a non-round bore shape with multiple waviness in the circumferential direction, with greater distance from this ripple decreases and closes in the direction of the bore exit after a transition, a rotationally symmetrical bore section (Third bore section BA3), which has an axial contour, which means, inter alia, that a surface line of the bore inner surface 15 is not parallel to the bore axis 112.
- the desired shape (shape) of the bore inner surface shows continuous changes of the surface shape without cracks or edges with merging one-dimensionally or two-dimensionally curved surface portions.
- This complex, non-circular cylindrical bore shape in the cold state of the workpiece is characterized in that it is calculated so that during operation of the engine, so with screwed cylinder head and running at operating temperature, by uneven deformation a more or less circular cylindrical Bore shape (operating mode) results so that result in typical operating conditions of the engine low blow-by, low oil consumption and low wear of the piston rings.
- the diameter differences within the first bore section BA1 between the transverse directions of the smallest and largest diameters may be, for example, of the order of a few tens of micrometers, seldom above 20 to 50 ⁇ m.
- the diameter differences between the mean diameter in the first bore section and the diameter in the vicinity of the bore exit may, for example, be in the range from 20 .mu.m to 200 .mu.m to 500 .mu.m.
- a finishing system having a machine tool is used.
- 3 schematically shows components of a fine processing system 300 according to an embodiment in the direction parallel to the x-direction of the machine coordinate system MKS.
- the fine processing system 300 comprises an NC-controlled, multi-axis machine tool 400.
- the machine tool shown as an example is designed as a honing machine having a plurality of simultaneously arranged in the x-direction and simultaneously operable processing units, which are sometimes referred to in dedicated honing machines as honing units.
- Fig. 3 shows some components of one of these processing units.
- a computer-based controller 415 controls the working movements of all movable components of the machine tool.
- the machine tool 400 is set up for the fine machining of cylinder surfaces in the production of cylinder blocks for internal combustion engines.
- a currently machined workpiece 100 is clamped firmly on a workpiece holding device 425.
- the position of the workpiece on the workpiece holding device is specified by indexing elements 426, so that a defined relationship exists between the workpiece coordinate system WKS and the machine coordinate system MKS.
- the work piece holding device has a horizontally movable slide 427, which can be moved under the control of the control unit 415 by means of a drive, not shown, parallel to the y direction of the machine coordinate system.
- a cross table which allow to move the workpiece in the x-y plane in any direction.
- variants with fixed positioned, non-movable workpiece holding device are possible.
- the workpiece is a cylinder crankcase of a four-cylinder in-line engine with four axially parallel cylinder bores.
- the next to be machined hole 1 10 is in the illustrated state as a result of the previous processing is substantially circular cylindrical and centered to the bore axis 112. It is intended by subsequent Fine machining operations are placed in a significantly different non-circular cylindrical nominal shape.
- the machining unit of the machine tool shown schematically is attached to a mounted on the machine bed of the machine tool, not shown support structure.
- the processing unit comprises a main spindle unit 430 with a headstock 435 serving as a support for the main spindle 410 of the processing unit.
- the headstock is the rotationally fixed component
- the main spindle is a shaft rotatably mounted therein.
- the main spindle is guided with vertical main spindle axis 412 in the headstock.
- a first drive 440 serves as a rotary drive for the main spindle to rotate about the main spindle axis 412.
- the speed and rotational position of the main spindle can be specified variably and precisely.
- a second drive 450 serves as a lifting drive for the controlled displacement or displacement of the main spindle parallel to the main spindle axis 412.
- the working movements of the main spindle are controlled by the control unit 415, to which the drives 440, 450 are connected.
- the first drive (rotary drive) 440 for example, be attached to the headstock 435 and act directly or via a chain drive on the main spindle.
- the spindle box is fixedly mounted in the axial direction and the lifting drive moves e.g. a ball screw spindle, the main spindle relative to the headstock in the axial direction.
- the headstock may be displaced in a direction parallel to the y-direction and / or parallel to the x-direction of the machine coordinate system.
- magnetically mounted main spindle which are characterized, inter alia, in that the main spindle is magnetically supported in a magnetic bearing device of the headstock and against the magnetic bearing device via control of the bearing magnets to some extent radially to the main spindle axis 412 in any direction within the xy plane controlled shift can be.
- the machine tool illustrated in FIG. 3 is adapted to bring the bore into a non-circular-cylindrical bore shape starting from the initial cylindrical shape resulting from the preprocessing, by means of a grinding operation with axially and / or azimuthally uneven material removal.
- a grinding operation is also referred to as “shaping grinding operation” or “forming grinding” because the bore shape, ie the macro-shape of the bore, is purposefully changed in a grinding process by uneven grinding removal.
- a grinding tool unit 500 is used, which in the case of a ready-made machine tool is rigidly coupled by means of a coupling device 460 to the free lower end of the main spindle.
- the interface between grinding tool unit 500 and main spindle 410 is shown only schematically.
- To produce the rigid but detachable connection between the main spindle 410 and the grinding tool unit 500 it is possible, for example, to provide a correspondingly secured bayonet connection, a screw connection, a flange connection or a conical connection, for example with a hollow shaft taper (HSK).
- HSK hollow shaft taper
- the grinding tool unit has a main body 520 which defines a central body axis 522, which may also be referred to as the main axis of the grinding tool unit.
- the coupling to the main spindle is such that the main body axis 522 is coaxial with the main spindle axis 412, so that the grinding tool unit can be rotated by rotation of the main spindle in a rotation about the main body axis.
- the main body 520 carries (at least) a grinding spindle unit 550, which is mounted displaceably on or in the main body 520, either with fixed relation to this or else controlled with respect to the main body.
- the grinding spindle unit carries a grinding tool 560 that has an abrasive body 565 that can be rotated indefinitely about a grinding tool axis 562 using a grinding tool driver 580.
- the grinding tool drive is integrated in the grinding tool unit 500.
- the abrasive body 565 has substantially the shape of a grinding wheel of suitable height, which can be brought with its abrasive peripheral surface 567 in contact with the bore inner surface 1 15 in order to remove there by means of grinding (more precisely by means of peripheral grinding) material.
- the grinding tool axis 562 is aligned parallel to the main body axis 522 or to the main spindle axis 412 and lies at a radial distance eccentrically to the latter.
- the diameter of the abrasive body 565 is significantly smaller than the diameter of the bore, so that the abrasive body can be in abrasive contact with the bore inner surface at any time with its peripheral surface only with a relatively narrow engagement region.
- the diameter of the grinding wheel may be, for example, in the range between 90% and 10%, in particular between 20% and 50%, of the mean diameter of the bore to be machined.
- the diameter of the grinding wheel can be, for example, with regard to the order of magnitude the smallest to be generated contour to be selected, for example, depending on desired azimuthal bulges or waves.
- the position of the grinding tool axis 562 and the diameter of the grinding body 565 are coordinated so that the grinding body can protrude laterally beyond the outer contour of the main body 520, so that only the abrasive outer surface of the grinding body can come into contact with the bore inner surface.
- the grinding spindle unit 550 and the grinding tool 560 in the radial direction to the main body axis 522 infinitely deliverable, regardless of any lateral movements of the main spindle 410.
- the grinding spindle unit 550 is mounted in a support, not shown, which is within the main body 520 radially is slidably mounted and serves as a feed element of a feed device for the delivery of the grinding tool in the direction of the bore inner surface 1 15.
- the effective radius of the grinding tool ie the radial distance between the radially outermost side of the grinding wheel and the main body axis 520, can be infinitely adjusted.
- the feed device has an electrically controllable actuator 590, for example in the form of an electric motor or an actuator with piezoelectric elements.
- the fine machining system can be carried out by generating working movements of the grinding tool, a grinding operation with which the shape (shape) of the bore 1 10 can be selectively changed in a defined manner both in the axial direction and in the circumferential direction.
- the grinding tool unit is inserted into the bore parallel to its main spindle axis by lowering the main spindle until the grinding wheel is at an axial height where grinding is to begin.
- the grinding tool is rotated about the grinding tool axis by means of the grinding tool drive at a predeterminable speed. This speed can remain constant over time or vary.
- the abrasive peripheral surface 567 of the grinding wheel 565 of the grinding tool is brought into working engagement with the bore inner surface 15. This delivery is preferably carried out with already rotating abrasive.
- the axial position of the grinding tool in the bore can now be controlled by activating the second drive 450 (lifting drive) of the machine tool, while the angular position of the grinding tool in the bore is controlled by a Control of the first drive 440 (rotary drive) can be controlled. Since these movements can be controlled via the main spindle 410, the grinding tool unit can dispense with adjustment devices in the axial direction and the circumferential direction and thus be of relatively simple construction.
- the local material removal rate in the local engagement region between the peripheral surface 567 of the grinding body 565 and the bore inner surface 15 can be determined by a variation of the delivery of the grinding tool, a variation of the rotational speed of the grinding tool or of the grinding body and / or a variation of the contact time between the grinding body and the bore inner surface be controlled with high precision.
- the delivery position via actuation of the actuator 590 can be changed continuously and time-dependent.
- the position of the main spindle axis and the dependent therefrom base body axis can remain unchanged, so that variants of machine tools can be used, for example, allow no radial displacement of the main spindle in the direction perpendicular to the main spindle axis.
- the speed of the grinding wheel can be varied steplessly by driving the grinding tool drive 580 in order to vary the local cutting speed.
- Typical speeds may be, for example, in the range of 600 min 1 to 10,000 min 1 , possibly even higher.
- the contact time between the grinding wheel and the bore inner surface can be precisely controlled by means of the drives 440 and 450 of the machine tool. If, for example, the main spindle is only rotated when the lifting drive 450 is stationary, the local contact time in the axial area machined by the grinding wheel depends on the rotational speed of the main spindle in such a way that the local contact time with respect to a location on the bore inner surface becomes lower , the higher the speed of the main spindle. The same applies to a variation of the lifting speed. If this is slow, then the local residence time of the rotating grinding tool tends to be greater at a location of the inner surface than at a larger lifting speed.
- the material removal rate ie the volumes scanned per unit time
- the material removal rate can be controlled very precisely for each location on the inside of the bore both in the axial direction and in the circumferential direction in order to obtain the desired non-circular-cylindrical bore shape from a starting shape by a controlled grinding operation.
- Fig. 4 shows a schematic view of a perpendicular to the bore axis 1 12 extending plane of the bore between the hole inlet and hole outlet in the generation of a non-round hole cross-section by grinding.
- the grinding wheel 565 rotates at high speed (double arrow) around the Schleiftechnikmaschinese 562, while the entire grinding tool unit is rotated about the coaxial to the bore axis extending body axis at a much slower rotational speed (for example 10 to 50 min 1 ).
- the grinding spindle unit is delivered several times radially outward and then gradually retracted back radially inward. Due to the multiple alternation of outward delivery and retrieval inward during a rotation, the circumferentially wavy bore shape is created in the illustrated bore portion.
- a feed of the grinding tool unit takes place parallel to the main spindle axis or to the bore axis 15, so that the non-circular bore shape can be generated over a longer bore section.
- the extent of the waviness may remain constant in the axial direction, but may also increase or decrease in the axial direction, for example, in such a way that in a more distant bore plane of the bore cross-section is increasingly circular or the ripple is less pronounced.
- FIG. 5 shows another embodiment of a grinding tool unit 500-5 that is rigidly coupled to the free end of a main spindle 410.
- the abrasive tool unit may be referred to as a built-in abrasive tool that is driven by a motor 580-5.
- a fine adjustment is possible in that the grinding spindle unit has a magnet-mounted grinding spindle, which allows a radial displacement of the grinding spindle within the magnetic bearing.
- the grinding spindle unit 550-5 has a spindle housing with a magnetic bearing device which supports the rotatable shaft which carries at its free end the grinding wheel 565-5. There is an air gap between the shaft and the magnets of the bearing. This makes it possible to move the rotatable component (shaft with attached abrasive 565-5) relative to the spindle housing radially to Schleifwerkmaschineachse 562-5 in any radial directions, for example, in the order of 10 pm to 20 pm to 200 pm referred to a centered zero position.
- the grinding spindle unit 550-5 as a whole is in a radially displaceable feed element stored, which can be displaced by means of the electric motor 590-5 radially to the main body axis 522-5. With this motor a radial coarse feed of the 565-5 grinding wheel is possible. This infeed may be superimposed on a fine feed by means of the magnetically supported spindle.
- the grinding tool unit 500-5 is shown in two axial positions.
- an upper bore portion is machined using the abrasive body 565-5 substantially without axial contour (generatrices at the bore portion approximately parallel to the bore axis).
- This bore portion may, for example, be circular-cylindrical or have a non-circular shape, for example an oval or elliptical shape or a cloverleaf shape.
- This bore section in which the bore diameter increases continuously with increasing distance from the bore entry.
- This bore portion may, for example, be conical or frustoconical.
- the feed of the grinding spindle unit during the grinding operation is controlled so that the radial feed position increases linearly in the lower portion with increasing distance from the bore entrance.
- An intermediate position near the hole entry is shown with dashed lines.
- FIG. 6 shows a further embodiment of a grinding tool unit 500-6, which can be rigidly coupled to a main spindle 410.
- the grinding spindle unit 550-6 is attached to a feed element 575, which is mounted radially displaceable within the main body 520-6.
- the associated feed device has a feed cone 570, which is axially displaceably guided in a coaxially to the main body axis 522-6 extending guide opening and in the vicinity of its free end has an inclined surface which cooperates with a corresponding inclined surface of the Zustellelements to this radially move when the infeed cone is moved axially.
- the grinding spindle unit can thus be delivered radially by axial displacement of the feed cone 570.
- the grinding spindle unit has a magnetically supported spindle, so that the shaft of the grinding spindle unit, which carries the grinding body, can still be displaced within its bearing radially to its axis of rotation. This enables a combination of coarse feed (via actuation of the feed cone) and fine feed (via electrical control of the magnetically supported spindle).
- Fig. 7 shows schematically another embodiment of a grinding tool unit 500-7.
- the grinding spindle unit 550-7 is radially offset from the base body axis as in other embodiments and radially adjustable by means of a feed device to the main body axis to adjust the radial distance between the radial outside of the grinding wheel 565-7 and the main body axis.
- a special feature consists in that the grinding tool unit has an expandable guide group 580-7 with a plurality of guide strips 582 distributed around the circumference of the main body, which can be radially adjusted by means of a guide group feed system with a feed cone 585 that can be displaced axially within the main body.
- the guide strips may for example consist of hard metal and be polished on their radial outer sides, so that there are smooth, non-cutting guide surfaces.
- the expandable guide assembly allows the abrasive tool assembly to be supported within the bore against the effects of lateral forces caused by grinding. When using such a grinding tool unit, this can be hinged to the main spindle and there are no external guides for the axial guidance of the up and down movement of the grinding tool unit necessary.
- the grinding tool unit 500-7 can be used, for example, when a link rod is interposed between the main spindle of the machine tool and the tool, for example to compensate for an axial offset between the position of the main spindle axis and the desired position of the bore axis.
- FIG. 8 shows a grinding tool unit 500-8 with an integrated grinding wheel 565-8 driven by a motor 580-8.
- the grinding spindle unit 550-8 which carries the grinding wheel 565-8, is mounted in a fixed position in the tool or its basic body 520-8, so it can not be adjusted relative to this.
- a radial feed of the grinding wheel in the direction perpendicular to the grinding tool axis 562-8 is possible in this embodiment in that the grinding tool unit is mounted on a main spindle 410-8, which is radially displaceable (in directions perpendicular to the spindle axis 412-8). In these cases, therefore, the feed position of the grinding tool is changed by radial displacement of the main spindle relative to a normal position.
- This can be achieved, for example, by providing the machine tool with a magnetically-mounted main spindle which permits limited relative radial displacement of the rotatable part of the main spindle unit (ie the main spindle) with respect to the stationary part of the main spindle unit (namely the main spindle bearing means).
- the non-rotary part of the main spindle unit can be displaced controlled in the radial direction, also such a radial displacement for time-dependent control, the radial position of the grinding body can be used within the bore.
- the working position of the grinding wheel relative to the workpiece or bore could also be changed by moving the workpiece relative to a main spindle held stationary in a plane perpendicular to the main spindle axis during the grinding operation. Also, combinations of displacements of the main spindle and the workpiece in directions perpendicular to the main spindle axis may be used to control the working position of the abrasive article relative to the workpiece.
- the delivery of the grinding wheel can be done via tool-internal facilities and / or machine-side facilities.
- a grinding operation may be performed in which the local rate of material removal in a local engagement region between the abrasive article and the bore inner surface may be selectively controlled by varying one or more process parameters to obtain the desired desired shape of the bore upon completion of the grinding operation by a grinding process ,
- the bore inner surface typically has grinding marks R1 after completion of the grinding operation, which are more or less circumferentially of the bore and / or at a small angle thereto due to the high speed of the grinding wheel compared to the other working movements.
- the bore inner surface may thereafter have a Abrasive structure, which is not yet optimal for the intended use of the bore workpiece.
- At least one further machining operation follows, with the aid of which the inner surface of the bore is finished in order to achieve the ultimately desired surface structure and possibly bore shape.
- one or more honing operations follow after the grinding operation, which can be carried out by means of suitable honing tools (at least one honing tool).
- the illustrated machine tool coupled to the grinding tool unit may be specially designed to perform form grinding operations.
- subsequent honing operations take place on the same machine tool.
- the grinding tool unit is decoupled from the main spindle, a honing tool is coupled to the main spindle and at least one honing operation is performed on the bore inner surface by means of the honing tool.
- a grinding tool unit could also be constructed so that it has a separately deliverable cutting group for performing a honing operation. In this case, a tool change for performing this honing operation would not be required.
- a downstream honing operation can be designed so that the shape of the hole again specifically changed and thus the bore is brought into the final desired bore shape.
- Such a shape-changing honing operation typically has a significantly lower material removal than the preceding grinding operation.
- downstream honing operations are essentially intended to eliminate only the surface structure resulting from the grinding and to provide the surface structure desired for the intended use (for example with honing marks crossing each other at suitable angles) without substantially changing the macro-shape. In doing so, they more or less follow the cutting material bodies of the honing tool of the shape produced by the grinding without changing them.
- honing honing for example, specially designed honing tools may be used whose cutting material bodies are only slightly abrasive (fine-grained grinding wheels) and / or their grinding bodies are held elastically yielding, so that they can essentially follow a contour of the bore previously created by grinding without significantly changing the macro-shape of the hole.
- honing honing particularly suitable honing tools are disclosed for example in DE 10 2013 204 714 A1 or DE 10 2014 212 941 A1 of the applicant. The disclosure of these documents relating to the structure and function of honing tools is incorporated herein by reference.
- the follow-up honing operation may be performed by means of a honing tool having a tool body and an expandable annular cutting group having a plurality of cutting bodies distributed about the circumference of the tool body whose axial length measured in the axial direction is less than an effective outside diameter of the cutting group with the cutting bodies fully retracted. Due to the relatively short axial length of the cutting material body of the cutting group such Hontechnikmaschinee are particularly well suited for tracking an existing axial contour of a hole.
- the cutting material bodies can be elastically yielding, so that they can follow a bore contour particularly well, even in non-circular bore sections.
- Each of the abrasive tool units shown has exactly one grinding spindle unit with a single abrasive wheel.
- the associated grinding wheels may e.g. circumferentially offset from one another, e.g. diametrically opposite in pairs.
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- Engineering & Computer Science (AREA)
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- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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DE102018206113.0A DE102018206113A1 (de) | 2018-04-20 | 2018-04-20 | Feinbearbeitungsverfahren zum Herstellen einer nicht-kreiszylindrischen Bohrung sowie Feinbearbeitungssystem und Schleifwerkzeugeinheit |
PCT/EP2019/059161 WO2019201717A1 (de) | 2018-04-20 | 2019-04-10 | Feinbearbeitungsverfahren zum herstellen einer nicht-kreiszylindrischen bohrung sowie feinbearbeitungssystem und schleifwerkzeugeinheit |
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EP3781352A1 true EP3781352A1 (de) | 2021-02-24 |
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EP19717836.1A Pending EP3781352A1 (de) | 2018-04-20 | 2019-04-10 | Feinbearbeitungsverfahren zum herstellen einer nicht-kreiszylindrischen bohrung sowie feinbearbeitungssystem und schleifwerkzeugeinheit |
Country Status (3)
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EP (1) | EP3781352A1 (de) |
DE (1) | DE102018206113A1 (de) |
WO (1) | WO2019201717A1 (de) |
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JP6708300B2 (ja) * | 2017-03-30 | 2020-06-10 | 工機ホールディングス株式会社 | 回転工具 |
CN113492355B (zh) * | 2021-05-07 | 2022-06-07 | 南京航空航天大学 | 一种液压偶件精密珩磨孔径预测及控制方法 |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2731554A1 (de) * | 1977-07-13 | 1979-01-18 | Christensen Inc | Innenschleifvorrichtung |
GB2310704A (en) | 1996-03-02 | 1997-09-03 | Ford Motor Co | Forming cylinder bores |
DE10054122B4 (de) * | 2000-10-31 | 2019-05-16 | Emag Holding Gmbh | Schleifwerkzeug |
EP1321229B1 (de) | 2001-12-20 | 2009-04-08 | Gehring GmbH & Co. KG | Verfahren zur Herstellung einer Bohrung |
EP2277662B1 (de) | 2005-11-25 | 2013-09-25 | Nagel Maschinen- und Werkzeugfabrik GmbH | Verfahren zum Honen von Bohrungen sowie Honmaschine |
DE102006062665A1 (de) * | 2006-12-29 | 2008-07-03 | Gehring Gmbh & Co. Kg | Verfahren zur formändernden Bearbeitung einer Bohrung |
KR101020105B1 (ko) * | 2008-06-18 | 2011-03-09 | 김태환 | 실린더 내경 연삭방법 및 그 장치 |
DE102013204714B4 (de) | 2013-03-18 | 2024-06-06 | Elgan-Diamantwerkzeuge Gmbh & Co. Kg | Honverfahren und Honwerkzeug |
AT514624B1 (de) * | 2013-07-26 | 2016-03-15 | Wfl Millturn Tech Gmbh & Co Kg | Werkzeughalter, Werkzeugmaschine und Verfahren zum Innenbearbeiten, insbesondere Innenhonen, eines Werkstücks |
DE102013220507B4 (de) * | 2013-10-11 | 2015-11-05 | Gehring Technologies Gmbh | Vorrichtung und Verfahren zur Erzeugung einer nicht zylindrischen Innenfläche einer Bohrung |
DE102014212941A1 (de) | 2014-07-03 | 2016-01-07 | Elgan-Diamantwerkzeuge Gmbh & Co. Kg | Honwerkzeug und Honverfahren |
DE102014225164B4 (de) | 2014-12-08 | 2017-10-12 | Elgan-Diamantwerkzeuge Gmbh & Co. Kg | Feinbearbeitungsverfahren zum Herstellen einer rotationssymmetrischen Bohrung mit axialem Konturverlauf |
US10220479B2 (en) * | 2016-04-25 | 2019-03-05 | Toyota Jidosha Kabushiki Kaisha | Machining apparatus |
-
2018
- 2018-04-20 DE DE102018206113.0A patent/DE102018206113A1/de active Pending
-
2019
- 2019-04-10 WO PCT/EP2019/059161 patent/WO2019201717A1/de unknown
- 2019-04-10 EP EP19717836.1A patent/EP3781352A1/de active Pending
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WO2019201717A1 (de) | 2019-10-24 |
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