Device for Processing of Materials by Cutting and Cutting Unit with Oscillating Cutting Knife and Variable Cutting Angle of Inclination
20170305027 · 2017-10-26
Inventors
Cpc classification
B26F1/3806
PERFORMING OPERATIONS; TRANSPORTING
B26D7/015
PERFORMING OPERATIONS; TRANSPORTING
B26D7/2628
PERFORMING OPERATIONS; TRANSPORTING
B26F1/3813
PERFORMING OPERATIONS; TRANSPORTING
B26F2001/3886
PERFORMING OPERATIONS; TRANSPORTING
B26F2001/388
PERFORMING OPERATIONS; TRANSPORTING
B26D2007/2678
PERFORMING OPERATIONS; TRANSPORTING
Y10T83/865
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
Abstract
A device for cutting material on a supporting surface has at least one cutting unit, which can be motor-driven in a controlled manner above and across the supporting surface in a direction of an X- and Y-axis of a Cartesian coordinate system that is parallel to the material supporting surface. The at least one cutting unit comprises an oscillation drive and a cutting knife. The oscillation drive sets the cutting knife into linear oscillations having an oscillation axis that is perpendicular to an advancing direction of the cutting knife. For changing an angle of inclination of the oscillation axis with respect to the material supporting surface, the oscillation drive with the cutting knife is pivotable around a pivot axis that is parallel to the material supporting surface. The oscillation drive comprises an electric motor having a rotary drive shaft that is parallel to the material supporting surface. The rotary axis of the rotary drive shaft is aligned with the pivot axis.
Claims
1. A device for the cutting of material on a plane material supporting surface, the device having at least one cutting unit, wherein the at least one cutting unit can be motor-driven in a controlled manner above and across the material supporting surface in a direction of an X- and Y-axis of a Cartesian coordinate system that is parallel to the material supporting surface, wherein the at least one cutting unit comprises an oscillation drive and a cutting knife, wherein the oscillation drive sets the cutting knife into linear oscillations having an oscillation axis that is perpendicular to an advancing direction of the cutting knife, wherein for changing an angle of inclination of the oscillation axis with respect to the material supporting surface the oscillation drive with the cutting knife is pivotable around a pivot axis that is parallel to the material supporting surface, wherein the oscillation drive comprises an electric motor having a rotary drive shaft that is parallel to the material supporting surface, and wherein the rotary axis of the rotary drive shaft is aligned with the pivot axis.
2. The device according to claim 1, wherein the pivot axis and the rotary axis of the rotary drive shaft are perpendicular to the oscillation axis of the cutting knife and intersect the oscillation axis.
3. The device according to claim 1, wherein the electric motor of the oscillation drive has a motor housing, and wherein the rotary drive shaft projects from the motor housing and is supported in two bearings within the motor housing and in a further bearing outside of the motor housing beyond the oscillation axis.
4. The device according to claim 1, wherein the cutting unit comprises a linearly guided knife holder and further comprises a gear between the rotary drive shaft of the oscillation drive and the knife holder, wherein the gear converts the rotation of the rotary drive shaft into an oscillating movement of the knife holder along the oscillation axis.
5. The device according to claim 4, wherein the gear comprises an eccentric ring, wherein the eccentric ring is fixedly connected to the rotary drive shaft, and wherein the eccentric ring has an inner cylindrical surface that is concentric to the rotary axis of the rotary drive shaft and has an outer cylindrical surface that is eccentric to the rotary axis of the rotary drive shaft.
6. The device according to claim 5, wherein the gear further comprises a connecting rod, wherein one end of the connecting rod surrounds the eccentric ring, wherein the opposite end of the connecting rod is articulated to the knife holder, and further comprising a bearing between the eccentric ring and the one end of the connecting rod, wherein the bearing surrounds the eccentric ring.
7. The device according to claim 1, wherein the at least one cutting unit is mounted on a carrier and wherein the carrier is controllably movable in the direction of the X-axis and Y-axis of the Cartesian coordinate system.
8. The device according to claim 7, wherein the carrier is mounted to an arch or portal, wherein the arch or portal is controllably movable in the X-direction with respect to the material supporting surface and wherein the carrier is controllably movable in the Y-direction with respect to the arch or portal.
9. The device according to claim 7, wherein the at least one cutting unit comprises a holder for the oscillation drive, wherein the holder is attached to the carrier, and wherein the oscillation drive is pivotable around the rotary axis of the rotary drive shaft with respect to the holder.
10. The device according to claim 7, wherein the at least one cutting unit comprises a controlled tangential or rotary drive for active alignment of the cutting knife and wherein the controlled tangential or rotary drive is arranged between the oscillation drive and the carrier.
11. The device according to claim 10, wherein the at least one cutting unit comprises a holder for the oscillation drive, wherein the holder is attached to a drive shaft of the tangential or rotary drive, and wherein the oscillation drive is pivotable around the rotary axis of the rotary drive shaft with respect to the holder.
12. The device according to claim 10, further comprising means for compensating movements of the cutting knife in a direction of the Z-axis of the Cartesian coordinate system, that are caused by pivoting movements of the oscillation drive around the pivot axis, wherein the means for compensating comprise means for adjusting a level or height of the tangential or rotary drive and wherein the compensating movements in the direction of the Z-axis for adjusting the level or height of the tangential or rotary drive are equal to
K(z)=A×(1−cos α) where A is the distance of the pivot axis from the material supporting surface in the direction of the Z-axis and where α is the angle of inclination of the oscillation axis of the cutting knife with respect to the Z-axis.
13. The device according to claim 10, further comprising means for compensating movements of the cutting knife in a direction of the X-axis of the Cartesian coordinate system, that are caused by pivoting movements of the oscillation drive around the pivot axis, wherein the means for compensating comprise means for moving the arch or portal along the X-axis in an opposite direction, wherein the compensating movements in the direction of the X-axis are equal to
K(x)=A×sin α×cos β where A is the distance of the pivot axis from the material supporting surface in the direction of the Z-axis, where α is the angle of inclination of the oscillation axis of the cutting knife with respect to the Z-axis and where β is the angle of rotation of a drive shaft of the tangential or rotary drive with respect to an initial position.
14. The device according to claim 10, further comprising means for compensating movements of the cutting knife in a direction of the Y-axis of the Cartesian coordinate system, that are caused by pivoting movements of the oscillation drive around the pivot axis, wherein the means for compensating comprise means for moving the carrier along the Y-axis in an opposite direction, wherein the compensating movements in the direction of the Y-axis are equal to
K(y)=A×sin α×sin β where A is the distance of the pivot axis from the material supporting surface in the direction of the Z-axis, where α is the angle of inclination of the oscillation axis of the cutting knife with respect to the Z-axis and where β is the angle of rotation of a drive shaft of the tangential or rotary drive with respect to an initial position.
15. A cutting unit, comprising an oscillation drive, a holder for the oscillation drive and a cutting knife, wherein the oscillation drive sets the cutting knife into linear oscillations having an oscillation axis, which is perpendicular to an advancing direction of the cutting knife, wherein the oscillation drive with the cutting knife is pivotable with respect to the holder around a pivot axis that is perpendicular to the oscillation axis, wherein the oscillation drive comprises an electric motor having a rotary drive shaft and wherein the rotary axis of the rotary drive shaft is aligned with the pivot axis and intersects the oscillation axis.
16. The cutting unit according to claim 15, wherein the electric motor of the oscillation drive has a motor housing, and wherein the rotary drive shaft projects from the motor housing and is supported in two bearings within the motor housing and in a further bearing outside of the motor housing beyond the oscillation axis.
17. The cutting unit according to claim 15, wherein the cutting unit comprises a linearly guided knife holder and further comprises a gear between the rotary drive shaft of the oscillation drive and the knife holder, wherein the gear converts the rotation of the rotary drive shaft into an oscillating movement of the knife holder along the oscillation axis.
18. The cutting unit according to claim 17, wherein the gear comprises an eccentric ring, wherein the eccentric ring is fixedly connected to the rotary drive shaft, wherein the eccentric ring has an inner cylindrical surface that is concentric to the rotary axis of the rotary drive shaft and has an outer cylindrical surface that is eccentric to the rotary axis of the rotary drive shaft, wherein the gear further comprises a connecting rod, wherein one end of the connecting rod surrounds the eccentric ring, wherein the opposite end of the connecting rod is articulated to the knife holder, and further comprising a bearing between the eccentric ring and the one end of the connecting rod, wherein the bearing surrounds the eccentric ring.
19. The cutting unit according to claim 15, further comprising a controlled tangential or rotary drive for active alignment of the cutting knife.
20. The cutting unit according to claim 19, further comprising: a holder for the oscillation drive, wherein the holder is attached to a drive shaft of the tangential or rotary drive, and wherein the oscillation drive is pivotable around the rotary axis of the rotary drive shaft with respect to the holder; and a clamping ring for clamping the oscillation drive in various angular positions with respect to the holder.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
DETAILED DESCRIPTION OF THE DISCLOSURE
[0038] The device 10 shown in the drawing serves for the processing of material 12 by cutting, especially of layered material or plate-shaped material which has at least one plane surface for laying onto a flat support and which can be cut by a cutting knife, like cardboard, cork, foamed material, polystyrene, reboard or other sandwich slabs.
[0039] As shown best in
[0040] Furthermore, the device 10 has an arch or portal 22 which extends in a vertical distance from the material supporting surface 20 across the supporting or cutting table 14 and can be moved back and forth by a controllable portal drive (not shown) on tracks 24 or other linear guides in the direction of a horizontal X-axis of a Cartesian coordinate system that is parallel to the material supporting surface 20. The arch or portal 22 supports a carrier 26 for a cutting unit 30, which can be moved back and forth by a controllable carrier drive (not shown) on tracks 28 or other linear guides in the direction of a horizontal Y-axis of the Cartesian coordinate system. The cutting unit 30 can be removed from the carrier 26 so that in case of need it can be replaced by another processing unit, for example, a milling unit or marking unit.
[0041] The cutting unit 30 comprises a cutting knife 32, a knife holder 34, a linear guide 37 for the knife holder 34, an oscillation drive 36 for driving the knife holder 34 in an oscillating manner, a gear 38 arranged between the oscillation drive 36 and the knife holder 34, a tangential or rotary drive 44 for active alignment of the cutting knife 32, and a holder 40 that connects the oscillation drive to a drive shaft 42 of the tangential or rotary drive 44.
[0042] With the aid of the oscillation drive 36 and of the gear 38, the cutting knife 32 can be set into linear oscillations, the oscillation axis 46 of which is perpendicular to the advancing direction of the cutting knife 32, that is, the direction in which the cutting knife 32 moves across the material supporting surface 20 through the material 12 to be cut. When the cutting knife 32 cuts the material 12 along a cutting plane that is perpendicular to the material supporting surface 20, as represented in
[0043] As shown best in
[0044] The oscillation drive 36 comprises an electric drive motor with a cylindrical motor housing 54 and a motor shaft 56 that is supported within the motor housing 54 in two roller bearings (not visible). The motor shaft 56 comprises two shaft ends 58, 60, each of which projects from one of the two opposite ends of the motor housing 54. The shaft end 60 on the side of the gear 38 is supported with its free end in another roller bearing 62, so that the motor shaft 56 is rotatably supported in a total of three roller bearings. The roller bearing 62 is inserted into a recess that is coaxial to the rotary axis of the motor shaft 56 the recess being arranged in a removable bearing cover 64, which is fastened tightly with set screws 66 to the adjacent end of the motor housing 54. The roller bearing 62 can be lubricated through a bore 68 in the middle of the bearing cover 64.
[0045] The gear 38 has a gear housing 70, which consists of an upper part 72 arranged in extension of the motor housing 54 and a lower part 74 that protrudes downwardly. Both parts are connected to each other to form one piece. The gear housing 70 is fastened with set screws 76 to the adjacent end of the motor housing 54. The upper part 72 of the gear housing 70 is arranged between the end of the motor housing 54 and the bearing cover 64, where it partly overlaps a lower part of the end of the motor housing 54 and abuts the holder 40 with an abutment face 77 on the motor side. The upper part 72 surrounds a stepped bore 78, which is coaxial with the motor shaft 56, which extends to the adjacent end of the motor housing 54 and which is closed on its end facing away from the motor housing 54 by the bearing cover 64. The lower part 74 of the gear housing 70 surrounds a stepped bore 80, which is open toward the bottom and which is coaxial with the oscillation axis 46. The lower part 74 opens into the stepped bore 78 within the upper part 72 and is closed at its upper end above the motor shaft 56 by a plate 82.
[0046] The gear 38 is a crank mechanism for converting the rotation of the motor shaft 56 into an oscillating movement of the knife holder 34 along the oscillation axis 46. Within the gear housing 70 the gear 38 comprises an eccentric ring 84 that is arranged on the shaft end 60 between the adjacent end of the motor housing 54 and the bearing cover 64 in extension of the oscillation axis 46. The eccentric ring 84 has an inner cylindrical surface that is concentric to the rotational axis of the motor shaft 56 and an outer cylindrical surface that is eccentric to the rotational axis of the motor shaft 56. The eccentric ring 84 is fixedly attached to the motor shaft 56 so that it rotates together with the motor shaft 56.
[0047] Furthermore, the gear 38 comprises a connecting rod 86 which is made in one piece from light metal. The connecting rod 86 has a connecting rod head 88 surrounding the eccentric ring 84 and a connecting rod foot 90 which is articulated to the knife holder 34. Between the connecting rod head 88 and the eccentric ring 84 there is a closed needle bearing or ball bearing 92, the inner ring of which is pressed onto the cylindrical outer peripheral surface of the eccentric ring 84 whereas the outer ring is pressed into an eye of the connecting rod head 88. In order to accommodate the needle bearing or ball bearing 92, the width of the connecting rod head 88 is larger than that of the rest of the connecting rod 86 and of the connecting rod foot 90 in the axial direction of the motor shaft 56, as shown best in
[0048] The knife guide 37 consists of a cylindrical tube that is open at both ends, which is coaxial to the oscillation axis 46 and is inserted from below into a widened part of the stepped bore 80 and fixedly attached.
[0049] The knife holder 34 is a hollow cylindrical piston made of light metal, which is guided within the hollow cylindrical knife guide 37 so that it can move in the direction of the oscillation axis 46, wherein its outer peripheral surface slides during the oscillation movement with a slight clearance on the inner peripheral surface of the knife guide 37. For lubrication of these sliding surfaces a transverse bore 96 is provided, which extends through a wall of the lower part 74 of the gear housing 70, a wall of the hollow cylindrical knife guide 37 and a wall of the hollow cylindrical knife holder 34.
[0050] The knife holder 34 is provided on its open upper end with a transverse bore which is perpendicular to the oscillation axis 46. A holding bolt 98 made of hard metal is pressed into the transverse bore. The bolt 98 extends through a hard metal sleeve 100 in the connecting rod foot 90 of the connecting rod 86, which protrudes from above through the hollow cylindrical knife guide 37 a little distance into the open upper end of the knife holder 34.
[0051] As shown in
[0052] In order to facilitate the introduction of cuts into the material 12, where the cuts have a cutting face that is inclined with respect to the material supporting surface 20 at an acute angle, for example, 45 degrees or 60 degrees, the oscillation drive 36, together with the gear 38, the knife guide 37, the knife carrier 34 and the knife 32 can be pivoted with respect to the holder 40 around a pivot axis 106 that is parallel to the material supporting surface 20. The pivot axis 106 is aligned with the rotary axis of the motor shaft 56 and is perpendicular to the oscillation axis 46 of the cutting knife 32. In order to set a desired angle of inclination of the oscillation axis 46 of the cutting knife 32, additionally the oscillation drive 36 together with the components 32, 34, 36 and 38 can be positioned at any desired angular position with respect to the holder 40.
[0053] In the case of the cutting unit 30 in
[0054] In the cutting unit 30 in
[0055] For this purpose, the holder 40 comprises a plate-shaped projection 124 protruding sideways above the clamping ring 108 into which a step motor 126 is inserted so that it cannot rotate. The step motor 126 drives a pinion 128 which engages with a toothed-ring 130. The toothed ring is attached to the motor housing 54 so that it cannot rotate with respect to the motor housing 54 and is coaxial with the pivot axis 106. In order to set a desired angle of inclination of the oscillation axis 46, the step motor 26 can be driven in a controlled manner after the set screw 112 has been loosened in order to rotate the motor housing 54 in the through-opening 110 until the desired angle of inclination is reached.
[0056] When the angle of inclination of the cutting knife 32 is to be altered during a cutting operation, the clamping ring 108 remains loosened in order to be able to rotate the motor housing 54 by means of the step motor 126. On the other hand, when the cutting is to be performed with a constant angle of inclination, the set screw 112 is preferably tightened in order to reduce vibrations.
[0057] Fundamentally, the oscillation drive 36 can be turned through 360° in the through-opening 110 of the clamping ring 118 with respect to the holder 40; however, for the processing of the material 12 on the supporting surface 20, generally it is sufficient when the cutting knife 32, starting out from the state in
[0058] As a result of the pivotability of the oscillation drive 36 and of the gear 38 with respect to the holder 40, it becomes possible to provide a plate-shaped material 12 resting on the material supporting surface 20, for example, a reboard plate or a cardboard piece, with cuts 114, which are inclined with respect to the material supporting surface 20, as shown in
[0059] When two cuts 114 with opposite inclinations are made into the plate-shaped material 12, such that the lower ends of the cuts 114 come into contact somewhat above than the supporting surface 20, a groove that is open towards the top and has a V-shaped cross section can be cut out of the material 12. When the groove is straight, it is possible to tilt the parts of the plate-shaped material 12 around the base of the groove, until the surfaces of the groove abut each other. After that the two parts are inclined with respect to each other at an angle that corresponds to the opening angle of the groove cross section.
[0060] As shown best in
[0061] The holder 40 can be screwed onto the drive shaft 42 from below, as shown in
[0062] When the oscillation drive 36 is pivoted together with the gear 38, the knife holder 34 and the cutting knife 32 around the pivot axis 106, the distance between the tip 52 of the cutting knife 32 and the material supporting surface 20 will change. Furthermore, due the pivoting of the oscillation drive 36 and of the components 32, 34, 36 and 38 the tip 52 of the cutting knife 32 will deviate from the programmed movement path, which the tip 52 would follow in case of a vertical alignment of the oscillation axis 46 during the movement of the portal 22 and/or of the carrier 26, when viewed in a vertical projection.
[0063] For compensating the change of the vertical distance of the tip 52 of the cutting knife 32 from the material supporting surface 20, the level or height of the tangential or rotary drive 44 on the carrier 26 is adjustable, so that the drive 44 can be raised or lowered when there is a change of the pivot position of the cutting knife 32, as shown in
K(z)=A×(1−cos α)
[0064] where A is the vertical distance of the pivot axis 106 from the material supporting surface 20 and where α is the angle of inclination of the oscillation axis 46 of the cutting knife 32 with respect to its initial vertical position, as shown in
[0065] In order to compensate for the deviations of the tip 52 of the cutting knife 32 from the programmed movement path in the direction of the X- or Y-axis respectively, during a pivoting movement of the oscillation drive 36 around the pivot axis 106, the portal drive and/or the carrier drive are activated in order to move the portal 22 and/or the carrier 26 along the X-axis or Y-axis respectively in the opposite direction, where the movement of the portal 22 and/or the carrier 26 corresponds to the deviation. Here the degree of compensation in the direction of the X-axis, that is, the movement required of the portal 22 in the X-direction with respect to the cutting table 14, is:
K(x)=A×sin α×cos β.
[0066] The degree of compensation in the direction of the Y-axis, that is, the movement of the carrier 26 in the Y-direction with respect to the cutting table 14, which is necessary for the compensation, is:
K(y)=A×sin α×sin β,
[0067] where A is the vertical distance of the pivot axis 106 from the material supporting surface 20, where α is the angle of inclination of the oscillation axis 46 of the cutting knife 32 with respect to its initial vertical position, as shown in
[0068] With the device 10 described above, the cutting knife 32 can be driven with an oscillation frequency of 18,000 oscillations per minute and an exact piston or knife stroke of 1.6 mm. In comparison to a pneumatic cutting unit, the cut has an adjustable, constant cutting depth.
[0069] The oscillation frequency can be altered, since an rpm-controlled motor is used as the electric motor, while the piston stroke can be altered by replacing the eccentric ring 84 by another eccentric ring 84 with a larger or smaller eccentricity.
[0070] Although certain cutting devices and cutting units and features and characteristics thereof have been described herein in accordance with the teachings of the present disclosure, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the disclosure that fairly fall within the scope of permissible equivalents.