Modular Clamping Device

Abstract

To provide a clamp device configured so that a clearance for clamping a work-piece can be adjusted.SOLUTION: A clamp device 1 holds a work-piece 10 and a cutting tool in particular during machining using a grinding machine, where cutting of a peripheral edge of the work-piece is executed with a grindstone in an approximately cup-shape in particular. The clamp device comprises: a support unit provided to be mounted on the grinding machine; a clamp unit 20, supported on a clamp anvil holding element 22, which comprises a clamp anvil 12 that can be translationally driven to apply clamp force in parallel to a clamp axis line 16; and a driving unit 30 comprising a driving anvil 14. The clamp unit and the driving unit are provided as independent components attached to form a work-piece spindle stock of the grinding machine so as to be releasable or slidable from the support unit.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a modular clamping device for a grinding machine that performs peripheral grinding of a workpiece such as a cutting tool. Further, the present invention relates to a grinding machine.

Background Art

[0002] As a grinding machine for grinding a cutting tool, a grinding machine that grinds a cutting tool using a grinding tool, particularly a cup-shaped grinding wheel, is known. Hereinafter, the workpiece to be processed is generally referred to as a cutting tool, and is designed, for example, as an indexable insert. The cup-shaped grinding wheel is composed of a grinding ring that provides an annular front surface called a grinding edge, and is coated with an abrasive. Further, the cup-shaped grinding wheel may be designed to be able to perform grinding even on the peripheral surface of a grinding annular portion that may be cylindrical and / or conical on the outside and / or inside. A rotatably drivable grinding spindle transports the cup-shaped grinding wheel. The grinding spindle is attached to a bearing block of a grinding spindle headstock and is driven by a grinding spindle motor. The bearing block is attached so as to be slidable and displaceable in the axial direction and the radial direction, particularly in the X direction and the Y direction, and all movements are controlled, for example, by central CNC control. Depending on the type of grinding machine device, an additional dressing device and a cleaning device may be attached to the grinding spindle headstock, as well as means for lubrication.

[0003] Generally, a cutting plate portion or a cutting tool such as an indexable insert not only has different materials but also may have various basic geometric shapes such as square, triangular, diamond, rectangular, hexagonal, and / or round. For example, an exchangeable indexable cutting insert generally consists of a prism block having polygonal faces, particularly upper and lower faces, which are known to be connected together by circumferentially extending side faces consisting of a plurality of surface portions, particularly flank faces and rake faces.

[0004] For the machining of workpieces, particularly for the grinding of cutting tools, it may be necessary to use a clamping device that attaches the workpiece to a holder adjacent to the grinding tool to expose the surface of the workpiece to be ground. This clamping device is provided to ensure a constant clamping pressure for accuracy and reproducibility during the grinding process against the impact of force. The workpiece is placed between two coaxially arranged cylinder-type clamping elements, such as a plunger or an anvil, which are received within the C-shaped yoke of the clamping device and are rigidly clamped. At least one of the plungers is axially movable to apply an axial clamping force to clamp the workpiece to be machined against the other. The other clamping element, the second plunger or anvil, forms a contact portion for supporting the clamping force to hold the workpiece in a predetermined direction. The clamping force is transmitted by a transmission element and applied by a rocker structure or a lever structure. Since the workpiece is only frictionally clamped between the plungers, a large clamping force that is constantly applied axially is required. The second plunger provided on one leg of the C-shaped yoke is configured to support this high clamping force.

[0005] The workpieces accommodated in the clamping device may, in the clamped state, have at least parallel surfaces such that each of them approaches one of the end faces of the clamping elements. However, non-parallel surfaces are also known. In the case where the workpiece to be ground, i.e., the cutting tool, has a hole, the workpiece may be positioned at the center within the clamping device by a centering plunger arranged on one of the clamping elements.

[0006] The clamping device is known to form part of a so-called workpiece spindle head. This is, for example, a group of assemblies attachable to a grinding machine by means of a rotating plate and provided to move a clamped workpiece about a plurality of independent axes of rotation. The workpiece spindle head comprises a casting providing at least a holding structure for the clamping device and is fixed to the grinding machine by any means. The casting is designed in one block, mostly in a C-shape, to provide rigidity. At one end of the casting, there is arranged a part of the clamping device consisting of at least an axially drivable clamping element, hereinafter referred to as a clamping anvil, and at the other end of the casting, there is arranged a so-called drive device consisting of a clamping element rotatable about at least a clamping axis, a so-called B-axis, hereinafter referred to as a drive anvil. Generally, the clamping device is a large-sized complex device that results in a large casting for holding the clamping device.

[0007] For the grinding of a clamped workpiece such as a cutting tool, the cup-shaped grinding wheel of the grinding machine is controlled and guided axially and radially so as to contact the surface of the indexable insert to be ground. By rotation about the B-axis of the clamped workpiece, the cup-shaped grinding wheel can machine the entire circumferential surface of the clamped workpiece, for example, the clamped indexable insert. Further, as a result of a pivoting movement by rotating the clamping device about an axis perpendicular to the B-axis, named the A-axis, as a result of a rotational movement about the B-axis, as a result of a translational movement and / or a rotational movement of the grinding wheel about at least the X-axis and the Y-axis, the peripheral surface of the clamped cutting tool can theoretically be ground. Thus, for example, a 4-axis or 5-axis grinding machine is known having rotational movements about the axes of rotation, in particular the A-axis, the B-axis and the C-axis, and further translational axes related to the grinding tool, in particular the X-axis and the Y-axis.

[0008] For grinding different areas or regions of a cutting tool, such as a indexable insert, the determined surface orientation of the workpiece to be ground must be parallel to the polishing surface of the cup-shaped grinding wheel or generally the polishing surface of the grinding tool. One drawback of prior art clamping devices used in grinding machines having a cup-shaped grinding wheel is that due to their size, the clamping device is hardly pivotable relative to the cup-shaped grinding wheel for grinding one of the flat surfaces of the cutting tool or for proper positioning of the cutting tool clamped in another suitable grinding position. Since the available space is relatively limited, there is a risk of contact between the clamping device and the grinding tool.

[0009] Accordingly, known mounting devices are provided that unclamp the indexable insert and clamp it in another position in order to perform the next step of grinding. Nevertheless, the overall time required to grind the indexable insert, including the steps of clamping, unclamping and adjustment, increases, and thus the throughput of the grinding process decreases.

[0010] Performing the entire grinding process in one setting by providing at least one of the clamping elements in a long version such that the clearance between the two ends of the C-shaped casting is wide enough to pivot the clamping device relative to the cup-shaped grinding wheel to position the workpiece is well known, for example, as disclosed in Patent Document 1 (EP1579955). However, since the longitudinal axis path provided by one clamping element, particularly the clamping ram, is long, the rigidity of the clamping device decreases, resulting in inferior machining results. Furthermore, due to the C-shape of the holding element of the clamping device according to Patent Document 1, a clamping ram for applying a large clamping force in the axial direction is accommodated on one leg, which may cause bending of this leg and further deviation from the exact axial alignment of the two clamping rams.

[0011] Patent Document 2 (US5056766) proposes to slidably mount the clamping device so that the entire clamping device can be moved along the plane of the cup-shaped grinding wheel in order to avoid reclamping the indexable insert. Since this requires guide means on the grinding machine and the requirements for accuracy are high, the cost of such a grinding machine will increase.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Summary of the Invention

[0013] The present invention relates to a clamping device for a grinding machine of the type first cited in the prior art. The object of the present invention is to provide a clamping device for a grinding machine provided for manufacturing cutting tools such as indexable inserts economically and with high quality according to predetermined dimensional, shape and positional tolerances by means of peripheral grinding and profile grinding, thereby enabling high flexibility in grinding in one setting.

[0014] Furthermore, the clamping device can be combined with measuring means for determining, for example, the thickness of the individual workpieces clamped in the clamping device. Advantageously, the shape to be machined can be adapted according to the shape of the workpiece and can provide a smooth transition region between different surfaces and radii.

[0015] The object is achieved by a clamping device having the features of claim 1 and a grinding device having the features of claim 15. Advantageous embodiments of the present invention are specified in the dependent claims.

Problems to be Solved by the Invention

[0016] The problem is achieved by providing a clamping device for clamping a workpiece, in particular a cutting tool, the mounting clearance of which can be adjusted according to determination requirements set by grinding conditions for grinding the entire outer peripheral surface of the cutting tool with a cup-shaped grinding wheel.

[0017] According to the present invention, there is provided a clamping device for holding a workpiece, in particular a cutting tool, during machining on a grinding machine, wherein the peripheral grinding of the workpiece is carried out in particular by a generally cup-shaped grinding wheel.

Means for Solving the Problem

[0018] The clamping device includes a support unit provided to be attached to a grinding machine, a clamping unit, and a drive unit. The clamping unit is supported by a clamping anvil holding element and is translatable along a clamping axis to apply a clamping force. The drive unit includes a drive anvil connectable to a drive axis of the grinding machine and is rotationally drivable to rotate and orient the workpiece by the drive axis. In the clamping device, the clamping unit and the drive unit are provided as separate components. In the clamping device, at least one of the drive unit and the clamping unit is detachably or slidably attached to the support unit to form a workpiece spindle headstock of the grinding machine.

[0019] The clamping device is provided as a group of assemblies attachable to a grinding machine and is composed of a clamping unit, a drive unit, and a support unit.

[0020] The clamping unit comprises at least a clamping anvil that is rotatably supported and axially movable. The clamping anvil comprises a clamping shaft rotatably supported by bearings in the radial and axial directions on a clamping holding element, and a clamping pin. The clamping pin is exchangeably and coaxially inserted into the clamping shaft at an end protruding from the clamping holding element. The clamping anvil is driven to be translatable in the longitudinal direction of the clamping shaft in order to apply a clamping force for holding a workpiece between the clamping anvil and the drive anvil. The axially acting clamping force may be applied to the clamping anvil by a transmission means provided to transmit a clamping force that preferably does not include other force components as an axially directed force component generated by an actuating device. The actuating device for generating the axial clamping force may be a pneumatic or hydraulic cylinder unit that is preferably arranged parallel to the clamping axis and has an actuating rod acting on the transmission means. The transmission means comprises a lever device that will be described in detail later.

[0021] The drive unit forms a portion facing the clamping unit and forms a contact portion for supporting the applied clamping force. The drive unit comprises a drive anvil having a drive pin exchangeable with the drive axis. The drive axis extending coaxially with the clamping axis can be rotationally driven by the drive axis of the grinding machine, the so-called B axis. For example, the drive axis can be inserted with its shaft cone portion inserted into the receiving cone portion of the B axis. The drive axis may be fixed to the drive shaft bearing of the drive holding element, rigidly supported, and have very accurate concentricity. On the drive axis, it is provided for centering and fixing the workpiece. For example, the drive pin may be designed for centering and fastening the workpiece, or alternatively, the drive anvil may be provided such that a centering plunger is fastened at one end by a threaded portion screwed into a threaded hole provided in the longitudinal direction of the drive anvil.

[0022] The drive axis is rotationally driven about the B-axis by the actuating part and is immovable in the axial direction. By rotating about the B-axis, the clamped workpiece, in particular the clamped cutting tool, rotates. The drive anvil and the clamping anvil, which are aligned with high precision, form a clamping system for fixedly clamping the workpiece to be ground while the respective ends of the clamping pin and the drive pin face each other.

[0023] The support unit is accurately attached to the machine table of the grinding machine having the B-axis in such a way that the clamping axis of the clamping device is aligned with the B-axis. For this purpose, the support unit according to an embodiment of the present invention provides a guide element on the contact surface of the machine table that can be attached to a suitable guide of the machine table extending in a direction parallel to the B-axis. In this direction, the support unit can be positioned such that the drive axis of the drive unit is coupled to the B-axis. Alternatively, the support unit may be attached to the grinding machine via a rotating plate so as to be rotationally driven about a further rotation axis.

[0024] In one embodiment, at least one of the clamp unit and the drive unit is slidably attached to a support unit in the shape of a support plate. In order to accurately position at least one slidable unit in a direction parallel to the clamping axis, a linear guide element is provided on the surface of the support unit carrying the clamp unit and the drive unit, which coincides with a corresponding guide element provided on the surface on the opposite side of the clamp unit and / or the drive unit. The positions of the drive unit and the clamp unit relative to each other can be defined or selected by the user, for example, using a control unit. The guide member is well known in the art for accurately guiding the unit along the guide path with high rigidity, i.e., a dovetail groove guide. Further, means for securely fixing the positioned clamp unit and / or drive unit are also known in the art. Since it is possible to adjust the clearance between the clamp unit and the drive unit, the clamp unit and / or the drive unit can provide a so-called long version with higher flexibility and a so-called short version with higher rigidity.

[0025] For example, the long version of the drive device includes a drive pin in which the clamping axis extends longitudinally further from the drive holding element than in the short version in order to increase the distance between the drive holding element and the clamped workpiece. Alternatively or additionally, the clamping pin of the long version of the clamping unit extends further longitudinally than the short version so as to increase the distance between the clamped workpiece and the clamping holding element. The increased distance provided by the long clamping pin and the long drive pin increases the free access of the grinding wheel to the clamped workpiece. In other words, the space on both sides of the clamped workpiece, particularly a cutting tool, increases for positioning the clamped workpiece towards the cup-shaped grinding wheel. Advantageously, the improved accessibility of the workpiece to be ground enables the machining of more complex structures and shapes. Further, according to the present invention, the clamping unit and the drive unit can be displaced to a predetermined position without changing the distance between the clamping unit and the drive unit, whereby the workpiece to be machined can be positioned at any position along the clamping axis. Therefore, the center of rotation of the workpiece with respect to the machining axis is now outside the workpiece itself, opening up new possibilities for performing grinding operations.

[0026] The clamping device can be attached as a module or an assembly to the rotational drive axis of a conventional grinding machine without the need to increase the space. Thus, it is possible to configure a grinding machine having high rigidity for use in highly productive grinding.

[0027] In another embodiment of the present invention, the support unit has an L-shape in which one portion identified as the first leg projects substantially vertically from the support surface. The first leg is provided with a hole, and the axis of the hole extends parallel to the longitudinal extension of the support surface and coaxial with the clamp axis. In the hole of the leg configured as a bearing hole, one of the clamp unit and the drive unit is inserted and supported, while the other of these is removably attached to the support unit, particularly the support surface. In order to adjust the clearance between the clamp unit and the drive unit, an appropriate version of the clamp unit or the drive unit necessary for arranging the clamped workpiece relative to the grinding surface of the cup-shaped grinding wheel is selected.

[0028] For example, when it is necessary to grind not only the outer circumference of the workpiece but also the outer contour, a large turning range of the cup-shaped grinding wheel relative to the workpiece is required. For such a purpose, a long version of the clamp unit may be attached to the support to provide a more flexible configuration. This long version of the clamp unit provides a large distance to the workpiece clamped on the clamp device side. The replacement of the complete clamp unit is easily carried out and does not require further adjustment or calibration. By replacing at least one of the clamp device and the drive device, the clearance between the clamp device and the drive device is adjustable. Therefore, it is possible to avoid contact between the workpiece spindle headstock and the cup-shaped grinding wheel due to positioning. Advantageously, the long and short versions of the clamp unit and / or the drive unit can be arranged outside the grinding machine and can be accurately positioned on the grinding machine without further adjustment and calibration.

[0029] Preferably, the drive device is fixedly attached to the leg formed on the L-shaped support device, and the clamp device can be removably attached to a predetermined position to complete the workpiece spindle headstock.

[0030] Positioning means and mounting means are provided to securely position and mount the units of the clamping device to form the workpiece spindle table. For this purpose, the support unit constitutes interface means for positioning and mounting a unit removably attached, for example a unit of the clamping device, so that the replacement of the unit can be carried out with high precision.

[0031] To position a unit removably attached relative to the support surface of the support unit, in particular the support surface of the clamping unit, the positioning means comprises guide pins protruding from the support surface of the support unit to a predetermined position. The guide pins are guided into contact surfaces, in particular corresponding guide bushes provided on the clamping unit. This arrangement may likewise be reversed. The guide pins may be formed as circular cylindrical bodies. Further forms such as prisms are likewise possible. The guide bushes may be formed by roll bodies held within a cage, where the roll bodies may be balls or sliding elements. Alternatively, the support unit may constitute an isostatic interface providing six contact points for an isostatic (isobaric) mount generally used to relatively move and hold a part of a structure to a desired position relative to the rest of the structure. The contact points may be provided by rolls or balls held in V-grooves. Alternatively, the positioning may be provided by a positive mount such that the support surface need not be planar and may be configured as a free-form surface pair.

[0032] For the purpose of removably attaching one of the clamping unit and the drive unit to the support unit, the fastening means provided at the interface between the support surface and the contact surface may be made as a bayonet-type attachment mechanism, snap-type fixing, or screw-type fixing.

[0033] An operating device is provided that generates an axial clamping force and applies it to a clamping anvil in order to hold a workpiece in a clamping position. A power source that is a hydraulic or pneumatic cylinder unit is used to generate the clamping force. In particular, the hydraulic cylinder unit is preferably arranged outside the support unit and extends substantially parallel to the support surface. The operating device comprises an operating rod connected to transmission means for transmitting the force generated by the operating device to the clamping unit. The transmission means may be coupled to the clamping anvil via an arm of a lever device in such a way that the clamping anvil moves axially in response to the pivotal movement of the lever device. The lever device may be coupled to the operating rod of the operating device attached to the machining table of the grinding machine. The pivot of the lever device is attached to a bearing member fixedly attached to the clamping device.

[0034] According to one embodiment of the present invention, the lever device comprises two parts that are accurately positioned and connectable to each other in order to form a lever device connectable to the clamping device. The first part, which is responsible for the pivoting and connection of the operating device to the operating rod, is fixedly attached to the clamping device, particularly the support device. The second part, which has an arm connected to the clamping anvil, is provided to be removably attached, and in particular, is removably connected to the first part and removably connected to the clamping device. Therefore, the second part of the lever device can be exchanged in accordance with the replacement of the clamping device.

[0035] According to one embodiment of the present invention, measuring means are provided for measuring the clamped workpiece, particularly the blank workpiece before machining, during machining and after the completion of the machining process. The measuring means are capable of determining the position and orientation of the blank workpiece clamped in the clamping device, and are further made such that the dimensional values of the workpiece can be measured during machining. Thereby, the machining process executed on the grinding machine can be controlled and adapted.

[0036] According to one embodiment of the present invention, the clamping device comprises a cover (lid), in particular a cover element, removably attached to one side of the clamping unit in order to provide sealing against the environment. Further, depending on the design and / or material of the cover element, the attachable cover element will contribute to an increase in the rigidity of the clamping unit and ultimately of the clamping device. Alternatively, the cover element may be made of a flexible material such that it does not affect the accuracy of the system. Further, if the cover element is machined with high precision, the system is not affected with respect to deformation and high-quality accuracy is maintained. Further, the cover element may comprise an adjustment system that enables deformation of the clamping device in a controlled manner such that the relative position between the drive anvil and the clamping anvil can be adjusted. For example, an adjustment screw may be provided that generates a force to adjust the relative position between the clamping device, the drive device and / or the support device.

[0037] Preferred embodiments of the present invention are described in more detail herein with reference to the accompanying drawings, which are given by way of non-limiting example.

Brief Description of the Drawings

[0038]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Best Mode for Carrying Out the Invention

[0039] In different figures and parts of the present invention, similar details are indicated by similar reference numerals throughout the figures and their entire specifications. Reference numeral 1 indicates the entire clamping device according to the present invention.

[0040] FIG. 1 is a schematic side view of a clamping device 1 designed as part of a grinding machine, and in particular, it consists of a cup-shaped grinding wheel for machining a workpiece 10 such as a cutting tool clamped to the clamping device 1. The rotating plate 2 on the machine bed is movable in the direction of a first rotation axis identified as the C-axis (not shown). Further, the clamping device 1 is pivotable about the B-axis line 18. By pivoting the clamping device 1 about an A-axis line (not shown) perpendicular to the B-axis line 18 and by translational and / or rotational movements of the grinding wheel about at least the X-axis and Y-axis (not shown), the peripheral surface of the clamped workpiece 10 can be theoretically ground. The rotating plate 2 of the grinding machine holds, in particular, the workpiece spindle head that constitutes the clamping device 1.

[0041] A workpiece 10 such as a cutting tool, in particular a removable insert to be polished, is fixed, centered, and reliably clampable in the clamping device 1, particularly between the clamping anvil 12 and the drive anvil 14. The clamping anvil 12 is supported by a clamping device holding element 22 of the clamping unit 20 and is translatable along a clamping axis identified as the clamping axis 16 to apply a clamping force. The drive anvil 14 is supported by the drive unit 30 and is connected to the B-axis line 18, which is the drive axis of the grinding machine. Thus, during grinding, the workpiece 10 can be rotated about the B-axis line 18.

[0042] Although not shown in FIG. 1, the grinding spindle head arranged at a position away from the rotating plate 2 is provided with, in particular, a cup-shaped grinding wheel, and the grinding spindle head is pivotable and relatively movable with respect to the rotating plate 2. Therefore, in the grinding machine for performing grinding of the workpiece 10, a plurality of controlled operations are performed in cooperation with each other.

[0043] According to the first embodiment of the clamping device 1 of the present invention, the workpiece spindle head includes a driving device 30 and, more specifically, a supporting device 40 (not shown in detail). According to FIG. 1, the supporting unit 40 has one part that protrudes substantially vertically from the supporting plate portion 39 and is designed in an L-shape identified as the first leg portion 42. The first leg portion 42 is provided with a hole portion configured as a bearing hole portion, and the axis of the hole portion is coaxially aligned with the clamping axis 16 and extends parallel to the longitudinal extension line of the supporting plate portion 39. Inside the hole portion of the first leg portion 42, the driving device 30 includes a driving shaft 32 and an exchangeable driving pin 34, and is rotatably attached with a driving anvil 14. The driving shaft 32 can insert a driving cone into a receiving cone of the B-axis 18, where the B-axis 18 can be rigidly supported by a B-axis bearing of the driving holding element 30 to provide very accurate concentricity. The workpiece 10 can be fixedly attached to the driving pin 34 by connecting means.

[0044] According to the first embodiment, a clamping anvil 12 shown in FIG. 1 is provided as the counterpart of the driving anvil 14. The clamping anvil 12 is supported by the clamping unit 20 so as to be guided to move rotatably without axial play. The workpiece 10, particularly the removable insert, can be clamped between the driving anvil 14 and the clamping anvil 12 by arranging the workpiece 10 centered on the B-axis 18, and the clamping anvil 12 is moved by applying a force to the driving anvil 14 arranged as a counter ram. According to the first embodiment, the clamping unit 20 is a separate or individual component and can be detachably or slidably attached from the supporting unit 40 to form the workpiece spindle head of the grinding machine. The clamping unit 20 is attached to the supporting unit 40 such that the axis of the clamping anvil 12 and the axis of the driving anvil 14 are aligned with each other and aligned with the clamping axis 16. For this purpose, the supporting unit 40 may be provided on the contact surface 50 with positioning means 60 (not shown in FIG. 1).

[0045] The clamping force provided by the clamping unit 20 may be introduced in various ways. For example, it can be implemented by an operating device (not shown in FIG. 1). The operating device may comprise a power source such as a pneumatic or hydraulic cylinder unit such that the movement of the operating rod is transmitted to the clamping device 1, in particular to the clamping anvil 12, via transmission means. Further details of the transmission means will be described later.

[0046] Furthermore, in order to provide the sealing of the clamping device 20 against the environment, a cover element 70 is removably attached to the clamping device 20. Depending on the design and / or material of the cover element 70, the attachable cover element 70 can contribute to the increase in the rigidity of the clamping unit 20 and ultimately of the clamping device 1.

[0047] In FIG. 2, a schematic cross-sectional view of the clamping device 1 of the first embodiment is shown. As shown, the drive anvil 14 and the clamping anvil 12 may be designed to be replaceable. In FIG. 2, the clamping anvil 12, the clamping unit 20 and the drive anvil 14 are designed in a so-called short version. In this short version, the space between the clamping unit 20 and the drive unit 30 is small, and the structure of the clamping device 1 is compact and rigid. With such a design of the clamping device 1, the grinding device is particularly suitable for performing high-speed grinding of the workpiece 10 clamped by the clamping device 1 with improved rigidity.

[0048] Furthermore, the transmission means for applying the clamping force particularly comprises a lever unit 100, which will be described in detail with reference to FIG. 5.

[0049] FIG. 3 is a perspective view of the clamping device 1 according to the first embodiment, showing elements such as the support unit 40 and the clamping unit 20 and the cover element 70 separated from each other. The support unit 40 is formed in an L-shape having a first leg portion 42 for supporting the drive unit 30. According to the first embodiment of the clamping device 1 of the present invention, the clamping unit 20 is provided as an individual element that can be represented as a group in which the workpiece spindle headstock is assembled or mounted. The clamping unit 20 is supported by a clamping holding element 22, and the clamping holding element 22 provides a contact surface 24 oriented toward the support surface 41 of the support unit 40. To position the detachable clamping unit 20 on the support surface 41 of the support unit 40, an interface 43 is provided with positioning means such as a guide pin 44 protruding from the interface 43 of the support unit 40 to a predetermined position. The guide pin 44 is guided to a corresponding guide bush 45 (not shown) provided on the contact surface 24 of the clamping unit 20. This arrangement may be reversed as well. The guide pin 44 may be formed as a circular cylindrical body. Further forms such as a prism are similarly possible. The guide bush 45 may be formed by a roll body held in a cage, where the roll body may be a ball, a roller, or a slider. Further, fixing means 46 may be provided to fix the clamping unit 20 to the support unit 20.

[0050] The clamping unit 1 of the present invention consists in particular of measuring means for detecting the thickness of the workpiece 10 clamped in a fixed state between the clamping anvil 12 and the drive anvil 14. Accordingly, a measuring device 80 consisting of a measuring probe 83 is provided, whereby the measuring means 80 can be connected to the clamping unit 20 and, in this embodiment, is detachably attached to the support unit 40. The measuring means 80 comprises a measuring lever 81 and a measuring head 82. The contact between the measuring lever 81 and the measuring head 82 or the measuring probe may be made so as to prestress by a spring element. For example, the contact between the measuring lever 81 and the measuring head 82 can be configured like between balls, between a ball and a plane, between rolls and / or between a roll and a plane, etc. Furthermore, the measuring head 82 and the measuring probe 83 do not require direct contact for measurement, but may be provided for optical measurement. Different materials such as hardened steel, ceramic, sapphire or carbide can be applied to the contacting elements.

[0051] In FIG. 4, a schematic side view of the clamping device 1 according to the second embodiment is shown. The clamping device 1 according to the second embodiment shows its so-called long version. In particular, the clamping device 20 shows a different design, and the drive anvil 14 and / or the clamping anvil 12 protrude further from their bearings such that the clearance between the drive device 30 and the clamping device 20 is greater than that provided like in the short version according to the first embodiment. In this long version of the clamping device 1, not only are the drive anvil 14 and the clamping anvil 12 designed to extend in the longitudinal direction, but also the design of the clamping unit 20 itself is different from that of the short version. That is, the free space on both sides of the clamped workpiece 10 is increased in order to position the clamped workpiece 10 towards the cup-shaped grinding wheel. To provide rigidity to this long version configuration, the clamping unit 20 is different from the clamping unit 20 of the short version according to FIGS. 1 to 3. As shown in FIGS. 1 to 3, the clamping unit 20 is different from the clamping unit 20 of the short version.

[0052] FIG. 5 is a cross-sectional view of the clamping device 1 according to the second embodiment. In order to transmit the operating force of an operating unit 92 such as an operating cylinder unit supported by a support unit 40 of the clamping device 1, transmission means 90 is provided so as to be able to transmit a clamping force provided by a clamping unit 20 to securely clamp a workpiece 10 between a clamping anvil 12 and a drive anvil 14. The operating unit 92 is axially displaceable, acts on a spring force, and includes an operating rod (not shown in detail) connected to the clamping unit 20 via a lever device 100. Alternatively, the operating unit 92 may be configured as a double-acting cylinder. The lever device 100 includes a first arm portion 102 and a second arm portion 104 releasably connected to the first arm portion. The first arm portion swings about a shaft 106 pivotally supported by a bearing member provided in the support unit 40 of the clamping device 1. The second arm portion 104 is connectable to the clamping anvil 12 such that the clamping anvil 12 moves axially with respect to the clamping axis in response to the pivotal movement of the first arm portion 102, and thus in response to the operation of the operating unit 92. In the design of the lever device, the first arm portion 102 is arranged to remain within the support unit 40, and the second arm portion 104 is arranged to be replaceable. Thereby, the lever device 100 can be adapted to the version of the clamping device 20, particularly the short version of the clamping device 20 in FIGS. 1 to 3, or the long version of the clamping device 20 in FIGS. 4 to 6.

[0053] In FIG. 6, a perspective view of the clamping device 1 according to the second embodiment is shown, where elements such as the support unit 40 and the clamping unit 20, and a cover element 70 are shown separated from each other. The clamping unit 20 provides a contact surface 24 for attaching the clamping unit 20 to the support unit 40, particularly the support surface 41. Thus, the support surface 41 and / or the contact surface 24 provide corresponding guiding means 50 for each other. Further, an interface 43 of the support unit 40 for positioning and attaching the clamping unit 20 is provided as already described based on FIG. 3.

[0054] FIG. 7 is an exploded view of a part of the clamping device 1 according to the third embodiment. According to the third embodiment, the drive device 30, the clamping device 20, and the support device 40 are provided as individual elements that are detachably attached to each other. In this embodiment, the support unit 40 can provide a linear guide element that can be securely fixed at a position adjusted to the clearance between the drive unit 30 and the clamping unit 20 necessary for grinding the workpiece 10 with a cup-shaped grindstone on any surface of the workpiece to be machined, such that the drive unit 30 and / or the clamping unit 20 can slide toward each other in a direction parallel to the clamping axis 16.

[0055] Although the present disclosure has been described with reference to specific means, materials, and embodiments, those skilled in the art can easily identify the essential features of the present disclosure from the above description. On the other hand, as described in the following claims, various changes and modifications are possible to adapt to various applications and features. The present application provides, for example, the following aspects. [Aspect 1] A clamping device (1) for holding a workpiece (10), in particular a cutting tool, during machining on a grinding machine, wherein the peripheral cutting of the workpiece (10) is carried out, in particular, by a generally cup-shaped grinding wheel, the clamping device (1) comprising a support unit (40) provided to be mounted on a grinding machine, a clamping unit (20) comprising a clamping anvil (12) supported by a clamping anvil holding element (22) and being translatably drivable to apply a clamping force parallel to a clamping axis (16), a drive unit (30) comprising a drive anvil (14) supported on a drive axis (18) and being rotatably drivable to rotate and orient the workpiece (10) using the drive axis (18) and the clamping unit (20) and the drive unit (30) are provided as separate components detachably or slidably attached to form a workpiece spindle headstock of a grinding machine from the support unit (40). A clamping device (1) characterized in that. [Aspect 2] The support unit (40) is such that the clearance between the clamping unit (20) and the drive unit (30) is adjustable in the longitudinal direction of the clamping axis (16), and the support unit (40) comprises a guidance for slidably attaching at least one of the clamping unit (20) and the drive unit (30), and means for fixing at least one of the clamping unit (20) and the drive unit (30) in a predetermined position. The clamping device (1) according to Aspect 1. [Aspect 3] The support unit (40) has an L-shape with one leg (42) protruding perpendicularly from a support surface (41), a hole for supporting the clamping unit (20) or the drive unit (30) is provided in the one leg (42), and the other of the clamping unit (20) and the drive unit (30) is detachably attached to the support surface (41) of the support unit (40). The clamping device (1) according to Aspect 1 or 2. [Aspect 4] The support unit (40) comprises a positioning means (44) and a fixing means (46) on an interface (43) for detachably attaching at least one of the clamping unit (20) and the drive unit (30). The clamping device (1) according to Aspect 3. [Aspect 5] The positioning means (44) is made as a guide pin (44) protruding from the support unit (40) at a predetermined position, so that the guide pin (44) can be detachably attached from the support unit (40), or the support unit (40) can be detachably attached from the guide pin (44), and the guide pin (44) is guided corresponding to a guide bush (45) provided on one contact surface (24) of the clamp unit (20) and the drive unit (30). The clamp device (1) according to aspect 4. [Aspect 6] The guide pin (44) is formed in a cylindrical body, the guide bush (45) is formed in a roll body held in a cage, and the roll body may be a ball or a sliding body. The clamp device (1) according to aspect 5. [Aspect 7] The fixing means (46) may be a bayonet type attachment / detachment mechanism, snap fixing, or screw fixing. The clamp device (1) according to any one of aspects 4 to 6. [Aspect 8] The clamp device (1) includes an operating unit (92) having an operating rod that generates a clamping force and a transmission means (90) that transmits the clamping force to the clamp anvil (12) of the clamp device (1). The clamp device (1) according to any one of aspects 1 to 7. [Aspect 9] The operating unit (92) is integrally arranged in the clamp unit (1) and is provided as a pneumatic, hydraulic, or electromagnetic cylinder unit. The clamp device (1) according to aspect 8. [Aspect 10] The transmission means (90) includes a lever device (100) that transmits the force generated by the operating unit (92) to the clamp anvil (12) of the clamp device (1). The clamp device (1) according to aspect 8 or 9. [Aspect 11] The lever device (100) is made as a unit consisting of two parts that are detachably connected to each other. The first arm portion (102) is non - replaceably provided on the clamp unit (20), and the second arm portion (104) is replaceably provided on the clamp unit (20). The clamp device (1) according to aspect 10. [Aspect 12] Measuring means is provided to measure the dimensions of a workpiece (10) held in the clamping position by the clamp device (1). The clamp device (1) according to any one of aspects 1 to 11. [Aspect 13] The measuring means (80) includes a measuring lever (81) that contacts a measuring head (82) operable by the measuring lever. The clamp device (1) according to aspect 12. [Viewpoint 14] The measurement lever (81) of the measurement means (80) is arranged within the clamp unit (20) and is provided to actuate the measurement head (82) arranged within the support unit (40), the clamp device (1) according to Viewpoint 13 [Viewpoint 15] In a grinding machine for grinding the periphery of a workpiece (10) with a cup-shaped grinding wheel, The grinding machine, wherein the workpiece (10) is clamped at a predetermined position by the clamp device (1) according to any one of Viewpoints 1 to 14.

Claims

1. A clamping device (1) for holding a workpiece (10), in particular a cutting tool, during machining on a grinding machine other than a centerless grinding machine, wherein peripheral grinding of the workpiece (10) is carried out, in particular, by a generally cup-shaped grinding wheel, the clamping device (1) comprising: a support unit (40) provided to be mounted on the grinding machine; a clamping unit (20) comprising a clamping anvil (12) supported by a clamping anvil holding element (22) and being translatably drivable to apply a clamping force parallel to a clamping axis (16); a drive unit (30) supported on a drive axis (18) of the grinding machine and comprising a drive anvil (14) rotatably drivable to rotate and orient the workpiece (10) about the drive axis (18) as a rotation axis; and the clamping unit (20) and the drive unit (30) are provided as separate components detachably attached to or slidable in the support unit (40) to form a workpiece spindle headstock of the grinding machine. A clamping device (1), characterized in that.

2. The support unit (40) is configured such that a clearance between the clamping unit (20) and the drive unit (30) is adjustable in a longitudinal direction of the clamping axis (16), wherein the support unit (40) provides a guidance for slidably mounting at least one of the clamping unit (20) and the drive unit (30), and fixing means for fixing at least one of the clamping unit (20) and the drive unit (30) after sliding and positioning it at a predetermined position. The clamping device (1) according to claim 1, characterized in that.

3. The support unit (40) has an L-shaped configuration with one leg (42) protruding perpendicularly from a support surface (41), wherein a hole for supporting the clamping unit (20) or the drive unit (30) is provided in the one leg (42), and the other of the clamping unit (20) and the drive unit (30) is detachably attached to the support surface (41) of the support unit (40). The clamping device (1) according to claim 1 or 2, characterized in that. **Claim 4**: The clamping device (1) according to claim 3, which cites claim 2, wherein the support unit (40) comprises a positioning means (44) and the fixing means (46) on an interface (43) for removably attaching at least one of the clamping unit (20) and the drive unit (30). **Claim 5**: The positioning means (44) is formed as a guide pin (44) protruding from the support unit (40) at a predetermined position, so that the guide pin (44) can be removably attached from the support unit (40), or the support unit (40) can be removably attached from the guide pin (44), and the guide pin (44) is guided corresponding to a guide bush (45) provided on one contact surface (24) of the clamping unit (20) and the drive unit (30). The clamping device (1) according to claim 4 is characterized by this. **Claim 6**: The guide pin (44) is formed in a cylindrical body, the guide bush (45) is formed in a roll body held in a cage, and the roll body may be a ball or a sliding body. The clamping device (1) according to claim 5 is characterized by this. **Claim 7**: The fixing means (46) may be a bayonet type attachment / detachment mechanism, snap fixing, or screw fixing. The clamping device (1) according to any one of claims 4 to 6 is characterized by this. **Claim 8**: The clamping device (1) according to any one of claims 1 to 7, characterized in that it comprises an operating unit (92) having an operating rod for generating a clamping force and a transmission means (90) for transmitting the clamping force to the clamping anvil (12) of the clamping device (1). **Claim 9**: The operating unit (92) is integrally arranged in the clamping device (1) and is provided as a pneumatic, hydraulic or electromagnetic cylinder unit. The clamping device (1) according to claim 8 is characterized by this. **Claim 10**: The transmission means (90) comprises a lever device (100) for transmitting the force generated by the operating unit (92) to the clamping anvil (12) of the clamping device (1). The clamping device (1) according to claim 8 or 9 is characterized by this.

11. The lever device (100) is made as a unit consisting of two parts that are releasably connected to each other. The first arm portion (102) is non - replaceably provided on the clamping unit (20), and the second arm portion (104) is replaceably provided on the clamping unit (20). The clamping device (1) according to claim 10, characterized in that.

12. The clamping device (1) according to any one of claims 1 to 11, characterized in that a measuring means is provided to measure the dimensions of the workpiece (10) of an object held at a clamping position by the clamping device (1).

13. The clamping device (1) according to claim 12, characterized in that the measuring means (80) comprises a measuring lever (81) in contact with a measuring head (82) operable by the measuring lever.

14. The measuring lever (81) of the measuring means (80) is arranged within the clamping unit (20) and is provided to operate the measuring head (82) arranged within the support unit (40). The clamping device (1) according to claim 13, characterized in that.

15. In a grinding machine for grinding the periphery of a workpiece (10) with a cup - shaped grinding wheel, The grinding machine, wherein the workpiece (10) is clamped at a predetermined position by the clamping device (1) according to any one of claims 1 to 14.

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