METHOD FOR CONTROLLING A WALL SAW SYSTEM WHEN MAKING A CUT-OFF CUT

Description

Technisches Gebiet

[0001] The present invention relates to a method for controlling a wall sawing system when making a separating cut according to the preamble of claim 1. Stand der Technik

[0002] Wall sawing systems are also known from WO 2014 / 128095 A1, WO 2014 / 124912 A1 or WO 2014 / 124931 A1.

[0003] EP 1 693 173 B1 discloses a method for controlling a wall sawing system when making a separating cut in a workpiece between a first end point and a second end point. The wall sawing system comprises a guide rail and a wall saw with a saw head, a motorized feed unit that moves the saw head parallel to a feed direction along the guide rail, and at least one saw blade that is attached to a saw arm of the saw head and driven about a rotational axis by a drive motor. The saw arm is designed to be pivotable about a pivot axis by means of a pivot motor. By pivoting the saw arm about the pivot axis, the penetration depth of the saw blade into the workpiece is changed. The motorized feed unit comprises a guide carriage and a feed motor, wherein the saw head is mounted on the guide carriage and moved along the guide rail by the feed motor.A sensor system with a swivel angle sensor and a travel sensor is provided to monitor the wall saw system. The swivel angle sensor measures the current swivel angle of the saw arm, and the travel sensor measures the current position of the saw head on the guide rail. The measured values ​​for the current swivel angle of the saw arm and the current position of the saw head are regularly transmitted to a control unit on the wall saw.

[0004] The known method for controlling a wall sawing system is divided into a preparatory section and a processing of the separating cut controlled by the control unit. In the preparatory section, the operator specifies at least the saw blade diameter, the positions of the first and second end points in the feed direction, and the final depth of the separating cut; further parameters can be the material of the workpiece to be processed and the dimensions of embedded reinforcing bars. From the entered parameters, the control unit determines a suitable main cutting sequence of main cuts for the separating cut, wherein the main cutting sequence comprises at least a first main cut with a first main cutting angle of the saw arm and a first diameter of the saw blade used, as well as a subsequent second main cut with a second main cutting angle of the saw arm and a first diameter of the saw blade used.

[0005] After the controlled machining process has started, the saw head is positioned in a start position. In the start position, the saw arm is pivoted in a negative direction of rotation around the pivot axis and arranged at the negative first main cutting angle. The saw head is moved in a positive feed direction along the guide rail towards the second end point, with the saw arm in a pulling arrangement during machining. Before reaching the second end point, the saw head is stopped and moved back sufficiently far in a negative feed direction opposite to the positive feed direction. The saw arm is pivoted in a positive direction of rotation opposite to the negative direction of rotation from the negative first main cutting angle to a positive main cutting angle of the saw arm.

[0006] In a first variant, the saw arm is pivoted from the negative first main cutting angle to the positive first main cutting angle and the saw head is moved in the positive feed direction towards the second end point, with the saw arm in a pushing arrangement. When the second end point is reached, the feed direction is reversed and the saw head is moved in the negative feed direction towards the first end point, with the saw arm in a pulling arrangement. Before the first end point, the saw head is stopped and moved back sufficiently far in the positive feed direction. The saw arm is pivoted from the positive first main cutting angle to the negative first main cutting angle and the saw head is moved in the negative feed direction towards the first end point, with the saw arm in a pushing arrangement.

[0007] In a second variant, the saw arm is pivoted from the negative first main cutting angle to the positive second main cutting angle and the saw head is moved in the positive feed direction towards the second end point, with the saw arm in a pushing arrangement. When the second end point is reached, the feed direction is reversed and the saw head is moved in the negative feed direction towards the first end point, with the saw arm in a pulling arrangement. Before the first end point, the saw head is stopped and moved back sufficiently far in the positive feed direction. The saw arm is pivoted from the negative second main cutting angle to a positive main cutting angle and the saw head is moved in the negative feed direction towards the first end point, with the saw arm in a pushing arrangement.When the second main cut represents the final main cut, the saw arm is pivoted to the positive second main cut angle. When a third main cut is performed with a third main cut angle, the saw arm is pivoted from the negative second main cut angle to the positive third main cut angle of the third main cut. The process steps are repeated until the final depth of the cut is reached.

[0008] The known method for controlling a wall sawing system has the disadvantage that the saw head is reset before processing, in a pushing position with the saw arm. Resetting only positions the saw head and does not process the workpiece. The time required for positioning increases non-productive times, especially for short cuts. Darstellung der Erfindung

[0009] The object of the present invention is to develop a method for controlling a wall sawing system with high processing quality, in which the downtime for positioning the saw head and saw arm is reduced. High processing quality means, among other things, producing a separating cut with a narrow cutting gap.

[0010] This object is achieved according to the invention in the method for controlling a wall sawing system mentioned above by the features of the independent claim. Advantageous further developments are specified in the dependent claims.

[0011] According to the invention, prior to the start of the processing controlled by the control unit, a saw arm length of the saw arm, which is defined as the distance between the pivot axis of the saw arm and the rotational axis of the saw blade, a distance between the pivot axis and the top side of the workpiece, a first width for a blade guard used during the first main cut and a second width for a blade guard used during the second main cut are additionally determined, wherein the first and second widths are each composed of a first distance of the rotational axis to the first blade guard edge and a second distance of the rotational axis to the second blade guard edge, and the saw head is stopped during the processing controlled by the control unit in a position in which a pivoting movement of the saw arm into the negative second main cutting angle takes place, wherein after the pivoting movement of the saw arm into the negative second main cutting angle,the second boundary of the wall saw facing the second end point coincides with the second end point, wherein the second boundary of the wall saw is formed by a second upper exit point of the saw blade used facing the second end point on an upper side of the workpiece if the second end point represents a free end point without an obstacle, by a second saw blade edge of the saw blade used facing the second end point if the second end point represents an obstacle and processing is carried out without a blade guard, and by a second blade guard edge of the blade guard used facing the second end point if the second end point represents an obstacle and processing is carried out with a blade guard.

[0012] The inventive method for controlling a wall sawing system has the advantage that machining with a saw arm arranged in a pulling and pushing motion is possible, and non-productive times for positioning the saw head are reduced by appropriate position control of the saw head. A narrow cutting gap is achieved by generally performing the first main cut of the main cutting sequence with a saw arm arranged in a pulling motion, and by guiding the saw blade through the narrow cutting gap of the first main cut with the saw arm arranged in a pushing motion during the subsequent main cuts. A separating cut in which the saw arm is arranged alternately in a pulling and pushing motion has the advantage that the non-productive times required for positioning the saw head and pivoting the saw arm are reduced compared to machining with a saw arm arranged exclusively in a pulling motion.

[0013] For controlled processing of a separating cut, the control unit must know various parameters. These include the saw arm length, which is a fixed, machine-specific dimension of the wall saw, and the vertical distance between the pivot axis and the surface of the workpiece, which depends not only on the geometry of the wall saw but also on the geometry of the guide rail used.

[0014] If an endpoint represents an obstacle, the saw head's position is controlled via the blade guard edge facing the obstacle. With an asymmetrical blade guard, the first and second distances between the rotation axis and the blade guard edges are different, whereas with a symmetrical blade guard, the first and second distances between the blade guard edges are equal to half the width of the blade guard.

[0015] The control method according to the invention is characterized in that the second limitation of the wall saw coincides with the second end point after the pivoting movement of the saw arm into the negative second main cutting angle.After the swivel movement of the saw arm into the negative second main cutting angle, the second upper exit point of the saw blade in use coincides with the second end point when the swivel axis has a distance from the second end point of √[h 2 · (D 2 - h 2 )] + δ · sin(-α 2 ), where h 2 = h(-α 2 , D 2 ) = D 2 / 2 - Δ - δ · cos(-α 2 ) denotes the penetration depth of the saw blade in use into the workpiece at the negative second main cutting angle with the second diameter, the second saw blade edge of the saw blade in use coincides with the second end point when the swivel axis has a distance from the second end point of D 2 / 2 + δ · sin(-α 2 ), and the second blade guard edge of the blade guard in use coincides with the second end point when the swivel axis has a distance from the second end point of B 2b + δ · sin(-α 2 ).

[0016] In a first embodiment, the second main cut represents the last main cut of the main cutting sequence and the wall saw is moved to a final position after the second main cut.

[0017] The saw head is moved in the second main cut in such a way that a first boundary of the wall saw, facing the first end point, coincides with the first end point, wherein the first boundary of the wall saw is formed by a first upper exit point of the saw blade used on the upper side of the workpiece, facing the first end point, if the first end point represents a free end point without an obstacle, by a first saw blade edge of the saw blade used, facing the first end point, if the first end point represents an obstacle and processing is carried out without a blade guard, and by a first blade guard edge of the blade guard used, facing the first end point, if the first end point represents an obstacle and processing is carried out with a blade guard.

[0018] The first upper exit point of the saw blade used coincides with the first end point when the pivot axis is at a distance from the first end point of √[h 2 · (D 2 - h 2 )] - δ · sin(-α 2 ), where h 2 = h(-α 2 , D 2 ) = D 2 / 2 - Δ - δ · cos(-α 2 ) denotes the penetration depth of the saw blade used into the workpiece at the negative second main cutting angle with the second diameter, the first saw blade edge of the saw blade used coincides with the first end point when the pivot axis is at a distance from the first end point of D 2 / 2 - δ · sin(-α 2 ), and the first blade guard edge of the blade guard used coincides with the first end point when the pivot axis is at a distance from the first end point of B 2a - δ · sin(-α 2 ).

[0019] In a second embodiment, the main cutting sequence comprises a third main cut following the second main cut with a third main cutting angle of the saw arm, a third diameter of the saw blade used and a third width of the blade guard used with a first and second distance to the blade guard edges, wherein the saw arm is arranged in a pulling arrangement during the third main cut and the saw head is moved in the positive feed direction.

[0020] During the second main cut, the saw head is moved in the negative feed direction towards the first end point with the saw arm inclined at the negative second main cutting angle. During machining controlled by the control unit, the saw head is moved in such a way that after the swivel movement of the saw arm into the negative third main cutting angle, the first limit of the wall saw coincides with the first end point, whereby the first limit is formed by the first upper exit point of the saw blade in use if the first end point is a free end point with no obstacle, by the first saw blade edge of the saw blade in use if the first end point is an obstacle and machining is carried out without a blade guard, and by the first blade guard edge of the blade guard in use if the first end point is an obstacle and machining is carried out with a blade guard.

[0021] The method according to the invention is characterized in that the first limit of the wall saw, facing the first end point, is also used for control. After the saw arm pivots into the third main cutting angle, the first limit coincides with the first end point.Particularly preferably, the first upper exit point of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of √[h 3 · (D 3 - h 3 )] - δ · sin(-α 3 ), where h 3 = h(-α 3 , D 3 ) = D 3 / 2 - Δ - δ · cos(-α 3 ) denotes the penetration depth of the saw blade used into the workpiece at the negative third main cutting angle with the third diameter, the first saw blade edge of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of D 3 / 2 - δ · sin(-α 3 ), and the first blade guard edge of the blade guard used coincides with the first end point when the pivot axis has a distance from the first end point of B 3a - δ · sin(-α 3 ).

[0022] The first and second main cuts are performed with one saw blade and one blade guard, or alternatively, the first main cut is performed by a first saw blade and a first blade guard, the first saw blade having a first saw blade diameter and the first blade guard having a first blade guard width, and the second main cut is performed by a second saw blade and a second blade guard, the second saw blade having a second saw blade diameter and the second blade guard having a second blade guard width. The number of main cuts and the saw blade diameters used depend, among other things, on the specification of the saw blade, the hardness of the material, the power and torque of the saw blade drive motor, and the final depth of the severing cut.

[0023] In a preferred embodiment, the first main cut of the main cutting sequence represents a pre-cut and the saw head is positioned in a start position parallel to the feed direction after the start of the processing controlled by the control unit, wherein in the start position the first boundary of the wall saw facing the first end point coincides with the first end point after the pivoting movement into the negative first main cutting angle, wherein the first boundary is formed by the first upper exit point of the saw blade used if the first end point represents a free end point without an obstacle, by the first saw blade edge of the saw blade used if the first end point represents an obstacle and processing is carried out without a blade guard, and by the first blade guard edge of the blade guard used if the first end point represents an obstacle and processing is carried out with a blade guard.

[0024] Particularly preferably, in the starting position, the first upper exit point of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of √[h 1 · (D 1 - h 1 )] - δ · sin(-α 1 ), where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece at the negative first main cutting angle with the first diameter, the first saw blade edge of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of D 1 / 2 - δ · sin(-α 1 ), and the first blade guard edge of the blade guard used coincides with the first end point when the pivot axis has a distance from the first end point of B 1a - δ · sin(-α 1 ).

[0025] In an alternative preferred embodiment, the main cutting sequence comprises a pre-cut to be carried out before the first main cut with a zeroth main cutting angle of the saw arm, a zeroth diameter of the saw blade used and a zeroth width of the blade guard used with a first and second distance to the blade guard edges, wherein the saw arm is arranged in a pulling arrangement during the pre-cut and the saw head is moved in the negative feed direction.

[0026] After the start of the processing controlled by the control unit, the saw head is positioned in a start position parallel to the feed direction for the pre-cut, whereby in the start position the second limit of the wall saw, facing the second end point, coincides with the second end point after the pivoting movement into the positive zeroth main cutting angle.Particularly preferably, after the pivoting movement of the saw arm into the positive zeroth main cutting angle, the second upper exit point of the saw blade used coincides with the second end point when the pivot axis has a distance from the second end point (E 2 ) of √[h 0 · (D 0 - h 0 )] + δ · sin(+α 0 ), where h 0 = h(+α 0 , D 0 ) = D 0 / 2 - Δ - δ · cos(+α 0 ) denotes the penetration depth of the saw blade used into the workpiece at the positive zeroth main cutting angle with the zeroth diameter, the second saw blade edge of the saw blade used coincides with the second end point when the pivot axis has a distance from the second end point of D 0 / 2 + δ · sin(+α 0 ), and the second blade guard edge of the blade guard used coincides with the second end point when the pivot axis has a distance from the second Endpoint (E 2 ) of B 0b + δ · sin(+α 0 ).

[0027] The transition from the preliminary cut (zero main cut) to the first main cut can be carried out in various ways. The variants differ in how the remaining material from the preliminary cut is removed. In a first variant, the preliminary cut is carried through to the first end point and the material is completely removed in the preliminary cut. In a second variant, the saw arm is pivoted to the negative first main cutting angle before reaching the first end point and the remaining material is completely or at least partially removed. A third variant dispenses with the removal and pivots the saw arm directly from the positive zero pivot angle to the negative first main cutting angle.

[0028] In the first variant, the saw head is stopped during controlled machining in the positive feed direction when the first limit of the wall saw coincides with the first end point, whereby the first limit of the wall saw is formed by the first upper exit point of the saw blade used on the upper side of the workpiece if the first end point represents a free end point without an obstacle, by the first saw blade edge of the saw blade used if the first end point represents an obstacle and machining is carried out without a blade guard, and by the first blade guard edge of the blade guard used if the first end point represents an obstacle and machining is carried out with a blade guard.The first variant, with a free end point, is particularly suitable for large saw blade diameters and long guide rails; with small saw blade diameters and short guide rails, the end of the guide rail can be reached before the first upper exit point coincides with the first end point.

[0029] The saw head is then positioned in the positive feed direction so that the first limit of the wall saw coincides with the first end point after the pivoting movement of the saw arm into the negative first main cutting angle, wherein the first upper exit point coincides with the first end point when the pivot axis has a distance from the first end point of √[h 1 · (D 1 - h 1 )] + δ · sin(-α 1 ), where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece at the negative first main cutting angle with the first diameter, the first saw blade edge of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of D 1 / 2 + δ · sin(-α 1 ), and the first blade guard edge of the blade guard used coincides with the first end point coincides,if the pivot axis is at a distance from the first end point of B 1a + δ · sin(-α 1 ).,

[0030] In the second variant, the saw head is moved during the pre-cut in the negative feed direction such that after the swivel movement of the saw arm into the negative zeroth main cutting angle, the first limit of the wall saw coincides with the first end point, whereby the first upper exit point of the saw blade used coincides with the first end point when the swivel axis has a distance from the first end point of √[h 0 (D 0 - h 0 )] - δ · sin(-α 0 ), where h 0 = h(-α 0 , D 0 ) = D 0 / 2 - Δ - δ · cos(-α 0 ) denotes the penetration depth of the saw blade used into the workpiece at the negative zeroth main cutting angle with the zeroth diameter, the first saw blade edge of the saw blade used coincides with the first end point when the swivel axis has a distance from the first end point of D 0 / 2 - δ · sin(-α 0 ), and the first blade protection edge of the blade protection used coincides with the first end point,if the swivel axis has a distance from the first end point of B 0a - δ · sin(-α 0 ).,

[0031] In the second variant, the pre-cut is processed exclusively by pulling, and the saw arm is pivoted to the negative first main cutting angle before reaching the first end point. The second variant, with a free end point, is primarily used for small sawblade diameters and short guide rails, since the first variant is only of limited use for this configuration of sawblade diameter and guide rail length. Pivoting the saw arm increases the idle time for the cut.

[0032] After swiveling, the saw head is moved in the positive feed direction by a distance of at least 2δ · |sin(-α 0 )| and the saw head is then positioned so that the first boundary of the wall saw coincides with the first end point after the pivoting movement of the saw arm into the negative first main cutting angle, wherein the first upper exit point of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of √[h 1 · (D 1 -h 1 )] - δ · sin(-α 1 ), where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece at the negative first main cutting angle with the first diameter, the first saw blade edge of the saw blade used coincides with the first end point when the pivot axis has a distance from the first end point of D 1 / 2 - δ · sin(-α 1 ),and the first blade guard edge of the blade guard used coincides with the first end point when the pivot axis is at a distance from the first end point of B 1a - δ · sin(-α 1 ).,

[0033] Alternatively to removal and positioning, the saw head is moved in the positive feed direction in such a way that the first limit of the wall saw coincides with the first end point after the swivel movement of the saw arm into the negative first main cutting angle, whereby the first upper exit point of the saw blade used coincides with the first end point when the swivel axis has a distance from the first end point of √[h 1 · (D 1 - h 1 )] - δ · sin(-α 1 ), where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece at the negative first main cutting angle with the first diameter, the first saw blade edge of the saw blade used coincides with the first end point when the swivel axis has a distance from the first end point of D 1 / 2 - δ · sin(-α 1 ), and the first Blade protection edge of the blade protection used coincides with the first endpoint,if the pivot axis is at a distance from the first end point of B 1a - δ · sin(-α 1 ).,

[0034] In the third variant, the saw head is moved in the positive feed direction in such a way that the first limit of the wall saw coincides with the first end point after the swivel movement of the saw arm into the negative first main cutting angle, wherein the first upper exit point coincides with the first end point when the swivel axis has a distance from the first end point of √[h 1 · (D 1 - h 1 )] - δ · sin(-α 1 ), where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece at the negative first main cutting angle with the first diameter, the first saw blade edge of the saw blade used coincides with the first end point when the swivel axis has a distance from the first end point of D 1 / 2 - δ · sin(-α 1 ), and the first blade guard edge of the blade guard used coincides with the first endpoint,if the pivot axis is at a distance from the first end point of B 1a - δ · sin(-α 1 ).,

[0035] The third variant completely dispenses with the removal of residual material during the pre-cut. The distance is adjusted so that the first limit of the wall saw coincides with the first end point after the saw arm pivots into the negative first main cutting angle. The variant without removing residual material has the lowest downtime; however, a powerful drive motor capable of handling the greater cutting depth at the end point is required.

[0036] The method according to the invention applies to all main sections where the main cutting angle is less than or equal to a critical pivot angle. The critical pivot angle corresponds to ±90° if the end point represents an obstacle, and the critical pivot angle corresponds to 180° - arccos[Δ / (δ + D / 2)] if the end point represents a free end point without an obstacle. Ausführungsbeispiele

[0037] Embodiments of the invention are described below with reference to the drawings. These are not necessarily intended to represent the embodiments to scale; rather, where useful for explanation, the drawings are schematic and / or slightly distorted. With regard to additions to the teachings immediately apparent from the drawings, reference is made to the relevant prior art. It should be noted that numerous modifications and changes to the form and detail of an embodiment can be made without deviating from the general idea of ​​the invention. The features of the invention disclosed in the description, the drawings and the claims can be essential for the further development of the invention, both individually and in any combination.Furthermore, all combinations of at least two of the features disclosed in the description, the drawings and / or the claims fall within the scope of the invention. The general idea of ​​the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, or limited to an object that would be limited compared to the object claimed in the claims. For given dimensioning ranges, values ​​lying within the stated limits are also intended to be disclosed as limit values ​​and can be used and claimed as desired. For the sake of simplicity, the same reference numerals are used below for identical or similar parts or parts with identical or similar functions.

[0038] They show: FIG. 1 shows a wall sawing system with a guide rail and a wall saw; FIGS. 2A, B show the processing of a separating cut between a first and second free end point without an obstacle; FIGS. 3A, B show the processing of a separating cut between a first and second obstacle with a saw blade that is not surrounded by a blade guard; FIGS. 4A, B show the processing of a separating cut between a first and second obstacle with a saw blade that is surrounded by a blade guard; FIGS. 5A-K show the wall sawing system of the FIG. 1 when creating a cut between a first obstacle and a second free end point without an obstacle.

[0039] FIG. 1 shows a wall sawing system 10 with a guide rail 11, a tool device arranged displaceably on the guide rail 11 12 and a remote control 13. The tool device is designed as a wall saw 12 and comprises a processing unit14 and a motorized feed unit 15. The processing unit is designed as a saw head 14 and comprises a processing tool designed as a saw blade 16, that on a saw arm 17 and is driven by a drive motor 18 around an axis of rotation 19 is powered.

[0040] To protect the operator, the saw blade 16 is protected by a blade guard 21 which is attached to the saw arm 17 by means of a blade guard holder. The saw arm 17 is driven by a swivel motor 22 around a swivel axis 23 designed to be pivotable. The pivot angle α of the saw arm 17 determined with a saw blade diameter D of the saw blade 16, how deep the saw blade 16 into a workpiece to be machined 24 The drive motor 18 and the swivel motor 22 are housed in a device housing 25The motorized feed unit 15 comprises a guide carriage 26 and a feed motor 27, which in the embodiment is also arranged in the device housing 25. The saw head 14 is mounted on the guide carriage 26 and is moved along the guide rail 11 in a feed direction by the feed motor 27. 28 In the device housing 25, in addition to the motors 19, 22, 27, a control unit 29 to control the saw head 14 and the motorized feed unit 15.

[0041] A sensor device with several sensor elements is provided to monitor the wall sawing system 10 and the machining process. A first sensor element 32 is a swivel angle sensor and a second sensor element 33designed as a displacement sensor. The swivel angle sensor 32 measures the current swivel angle of the saw arm 17, and the displacement sensor 33 measures the current position of the saw head 14 on the guide rail 11. The measured values ​​are transmitted from the swivel angle sensor 32 and the displacement sensor 33 to the control unit 29 and used to control the wall saw 12.

[0042] The remote control 13 comprises a device housing 35, an input device 36, a display device 37 and a control unit 38, which is arranged inside the device housing 35. The control unit 38 converts the inputs of the input device 36 into control commands and data, which are transmitted to the wall saw 12 via a first communication connection. The first communication connection is designed as a wireless communication connection. 41 or as a communication cable 42The wireless communication connection is designed in the exemplary embodiment as a radio connection 41, which is located between a first radio unit 43 on the remote control 13 and a second radio unit 44 on the tool device 12. Alternatively, the wireless communication connection 41 can be in the form of an infrared, Bluetooth, WLAN, or Wi-Fi connection.

[0043] FIGN. 2A , B show the guide rail 11 and the wall saw 12 of the wall saw system 10 of the FIG. 1 when creating a separating cut 51 in the workpiece 24 of the workpiece thickness d. The separating cut 51 has a final depth T and runs in the feed direction 28 between a first end point E 1 and a second endpoint E 2 . As X-Direction is defined as a direction parallel to the feed direction 28, with the positive X-direction being directed from the first end point E 1 to the second end point E 2, and as Y -Direction is defined as a direction perpendicular to the X-direction into the depth of the workpiece 24.

[0044] The end point of a severance cut can be defined as a free end point without obstacles or as an obstacle. Both end points can be defined as free end points without obstacles, both end points as obstacles, or one end point as a free end point and the other end point as an obstacle. Overlapping may be permitted at a free end point without obstacles. Due to the overlapping, the cutting depth at the end point reaches the final depth T of the severance cut. In the example of the FIGN. 2A , B the endpoints E 1 , E 2 form free endpoints without obstacle, whereby an intersection is not permitted at the free first endpoint E 1 and an intersection has occurred at the second endpoint E 2 .

[0045] FIG. 2A shows the saw head 14 in an assembly position X 0 and the saw arm 17 in a home position of 0°. The saw head 14 is positioned by the operator using the guide carriage 26 in the assembly position X 0 on the guide rail 11. The assembly position X 0 of the saw head 14 lies between the first and second end points E 1 , E 2 and is determined by the position of the pivot axis 23 in the feed direction 28. The position of the pivot axis 23 is particularly suitable as a reference position. X Ref for monitoring the position of the saw head 14 and controlling the wall saw 12, since the X-position of the pivot axis 23 remains unchanged even during the pivoting movement of the saw arm 17. Alternatively, a different X-position on the saw head 14 can be defined as the reference position; in this case, the distance in the X-direction to the pivot axis 23 must also be known.

[0046] The X-positions of the first and second end points E 1 , E 2 are defined in the example by entering partial lengths. The distance between the mounting position X 0 and the first end point E 1 determines a first partial length. L 1 and the distance between the mounting position X 0 and the second end point E 2 a second partial length L 2 Alternatively, the X-positions of the endpoints E 1 , E 2 can be specified by entering a partial length (L 1 or L 2 ) and a total length L as the distance between the endpoints E 1 , E 2 .

[0047] The separating cut 51 is created in several partial cuts until the desired final depth T is reached. The partial cuts between the first and second end points E 1 , E 2 are defined as main cuts, and the cutting sequence of the main cuts is defined as the main cutting sequence. At the end points of the separating cut, additional corner processing can be performed, which is referred to as obstacle processing in the case of an obstacle and as overcut processing in the case of a free end point with an overlap.

[0048] The main cutting sequence can be set by the operator, or the control unit of the wall sawing system can determine the main cutting sequence based on several constraints. Typically, the first main cut, also known as the pre-cut, is performed at a reduced cutting depth and reduced drive motor power to prevent polishing of the saw blade. The subsequent main cuts are generally performed at the same cutting depth, but can also have different cutting depths. The constraints typically set by an operator include the cutting depth of the pre-cut, the pre-cut power, and the maximum cutting depth of the subsequent main cuts. The control unit can determine the main cutting sequence based on these constraints.

[0049] The main cuts of a separating cut are performed with one saw blade diameter or with two or more saw blade diameters. If multiple saw blades are used, processing generally begins with the smallest saw blade diameter. In order to mount the saw blade 16 on the saw arm 17, the saw blade 16 must be positioned in the basic position of the saw arm 17 above the workpiece 24. Whether this boundary condition is met depends on two device-specific variables of the wall sawing system 10: firstly, a vertical distance Δ between the pivot axis 23 of the saw arm 17 and a top 53 of the workpiece 24 and on the other hand from a saw arm length δ of the saw arm 17, which is defined as the distance between the rotation axis 19 of the saw blade 16 and the pivot axis 23 of the saw arm 17. If the sum of these two device-specific variables is greater than half the saw blade diameter D / 2, the saw blade 16 is arranged in the home position above the workpiece 24. The saw arm length δ is a fixed device-specific variable of the wall saw 12, whereas the vertical distance Δ between the pivot axis 23 and the surface 53 depends not only on the geometry of the wall saw 12 but also on the geometry of the guide rail 11 used.

[0050] The saw blade 16 is mounted on a flange on the saw arm 17 and is driven by the drive motor 18 around the rotation axis 19 during sawing operation. In the basic position of the saw arm 17, which is FIG. 2A As shown, the pivot angle is 0° and the rotation axis 19 of the saw blade 16 lies in the depth direction 52 above the pivot axis 23. The saw blade 16 is moved from the basic position at 0° into the workpiece 24 by a pivoting movement of the saw arm 17 about the pivot axis 23. During the pivoting movement of the saw arm 17, the saw blade 16 is driven by the drive motor 18 about the rotation axis 19.

[0051] To protect the operator, the saw blade 16 should be surrounded by the blade guard 21 during operation. The wall saw 12 can be operated with or without the blade guard 21. For example, to process the separating cut in the area of ​​the end points E 1 , E 2 , the blade guard 21 can be removed. If different saw blade diameters are used to process the separating cut, different blade guards with corresponding blade guard widths are generally also used.

[0052] FIG. 2B shows the saw arm 17, which rotates in a negative direction 54 is inclined at a negative pivot angle -α. The saw arm 17 is adjustable in the negative rotation direction 54 between pivot angles of 0° to -180° and in a positive rotation direction opposite to the negative rotation direction 54 55 adjustable between swivel angles of 0° to +180°. FIG. 2B The arrangement of the saw arm 17 shown is referred to as a pulling arrangement when the saw head 14 is moved in a positive feed direction 56. If the saw head 14 is moved in a negative feed direction opposite to the positive feed direction 56 57 moves, the arrangement of the saw arm 17 is called a pushing arrangement.

[0053] At a swivel angle of ±180°, the maximum penetration depth of the saw blade 16 into the workpiece 24 is achieved. The swivel movement of the saw arm 17 about the swivel axis 23 shifts the position of the rotation axis 19 in the X-direction and in the Y-direction. The displacement of the rotation axis 19 depends on the saw arm length δ and the swivel angle α of the saw arm 17. The displacement path δ x in the X-direction is δ · sin(±α) and the displacement δ y in the Y direction is δ · cos(±α).

[0054] The saw blade 16 creates in the workpiece 24 a cutting wedge in the form of a circular segment with a height h and a width b.The height h of the circular segment corresponds to the penetration depth of the saw blade 16 into the workpiece 24. The relationship D / 2 = h + Δ + δ cos(α) applies to the penetration depth h, where D is the saw blade diameter, h is the penetration depth of the saw blade 16, Δ is the vertical distance between the pivot axis 23 and the top side 53 of the workpiece 24, δ is the saw arm length and α is the first pivot angle, and the relationship b 2< = D / 2 8h - 4h 2< = 4Dh - 4h 2< = 4h (D - h) applies to the width b, where h is the penetration depth of the saw blade 16 into the workpiece 24 and D is the saw blade diameter.

[0055] The control of the wall saw 12 during the separating cut depends on whether the end points are defined as obstacles, and in the case of an obstacle, whether the processing is carried out with or without the blade guard 21. In the case of a free end point without an obstacle, the control of the wall saw 12 in the method according to the invention is carried out via upper exit points of the saw blade 16 on the upper side 53 of the workpiece 24. The upper exit points of the saw blade 16 can be calculated from the reference position X Ref of the pivot axis 23 in the X direction, the displacement path δ x of the rotation axis 19 in the X direction and the width b. An upper exit point facing the first end point E 1 is referred to as the first upper exit point 58 and an upper exit point facing the second end point E 2 is referred to as the second upper exit point 59.For the first upper exit point 58, X(58) = X Ref + δ x - b / 2 applies and for the second upper exit point 59, X(59) = X Ref + δ x + b / 2 applies with b = √[h · (D - h)] and h = h(α, D).

[0056] If the end points E 1 , E 2 are defined as obstacles, it is not possible to cross the end points E 1 , E 2 with the wall saw 12. In this case, the control of the wall saw 12 in the method according to the invention takes place via the reference position X Ref of the pivot axis 23 and the limitation of the wall saw 12. A distinction is made between machining without blade guard 21 and machining with blade guard 21.

[0057] FIGN. 3A , B show the wall sawing system 10 during the creation of a separating cut between the first end point E 1 and the second end point E 2 , which are defined as obstacles, wherein the processing is carried out without blade guard 21. When processing without blade guard 21, a first saw blade edge 61,which faces the first end point E 1, and a second saw blade edge 62, which faces the second end point E 2, the boundary of the wall saw 12.

[0058] The X-positions of the first and second saw blade edges 61, 62 in the X-direction can be calculated from the reference position X Ref of the pivot axis 23, the displacement path δ x of the rotation axis 19 and the saw blade diameter D. FIG. 3A shows the wall saw 12 with the saw arm 17 inclined in the negative direction of rotation 54 at a negative pivot angle -α (0° to -180°). For the first saw blade edge 61, X(61) = X Ref + δ · sin(-α) - D / 2 applies and for the second saw blade edge 62, X(62) = X Ref + δ · sin(-α) + D / 2 applies. FIG. 3B shows the wall saw 12 with the saw arm 17 inclined in the positive direction of rotation 55 at a positive pivot angle α (0° to +180°). For the first saw blade edge 61, X(61) = X Ref + δ · sin(α) - D / 2 applies and for the second saw blade edge 62, X(62) = X Ref + δ · sin(α) + D / 2 applies.

[0059] FIGN. 4A , B show the wall saw system 10 during the creation of a separating cut between the first end point E 1 and the second end point E 2 , which are defined as obstacles, with the processing being carried out with blade protection 21. When processing without blade protection 21, a first blade protection edge 71, which faces the first end point E 1, and a second blade protection edge 72, which faces the second end point E 2, the boundary of the wall saw 12.

[0060] The X-positions of the first and second blade guard edges 71, 72 in the X-direction can be calculated from the reference position X Ref of the swivel axis 23, the displacement path δ x of the rotation axis 19 and the blade guard width B. FIG. 4A shows the wall saw 12 with the saw arm 17 inclined at a negative swivel angle -α (0° to -180°) and the mounted blade guard 21 of the blade guard width B. With an asymmetrical blade guard, the distances of the rotation axis 19 to the blade guard edges 71, 72 are determined before the start of the controlled processing, whereby the distance to the first blade guard edge 71 is used as the first distance B a and the distance to the second blade protection edge 72 as the second distance B b be referred to.

[0061] For the first blade protection edge 71, X(71) = X Ref + δ · sin(α) - B a and for the second blade protection edge 72, X(72) = X Ref + δ · sin(α) + B b . FIG. 4B shows the wall saw 12 with the saw arm 17 inclined at a positive swivel angle α (0° to +180°) and the mounted blade guard 21 of blade guard width B. For the first blade guard edge 71, X(71) = X Ref + δ · sin(α) - B a applies and for the second blade guard edge 72, X(72) = X Ref + δ · sin(α) + B b applies.

[0062] FIGN. 2A , B show a cut between two endpoints E 1 , E 2 , which are defined as free endpoints without obstacle, and FIGN. 3A , B and 4A, B show a separating cut between two end points E 1 , E 2 , which are defined as obstacles. In practice, separating cuts are also possible in which one end point is defined as an obstacle and the other end point represents a free end point without an obstacle, whereby the control of the wall saw at the free end point is via the upper exit point of the saw blade and at the obstacle via the saw blade edge (processing without blade guard 21) or the blade guard edge (processing with blade guard 21).

[0063] The first upper exit point 58, the first saw blade edge 61 and the first blade protection edge 71 are summarized under the term "first boundary" of the wall saw 12 and the second upper exit point 59, the second saw blade edge 62 and the second blade protection edge 72 are summarized under the term "second boundary".

[0064] FIGN. 5A-K show the wall saw system 10 of the FIG. 1 with the guide rail 11 and the wall saw 12 when creating a separating cut of the final depth T in the workpiece 24 between a first end point E 1 , which represents an obstacle, and a second end point E 2 , which represents a free end point without an obstacle.

[0065] In the method according to the invention, the separating cut is created in a main cutting sequence of several main cuts until the desired final depth T is reached. In addition to the main cutting sequence, corner machining in the form of obstacle machining is carried out at the first end point E 1 and corner machining in the form of overcut machining is carried out at the second end point E 2, whereby the corner machining at the first and second end points is not part of the method according to the invention. The main cutting sequence comprises a first main cut with a first main cutting angle α 1 of the saw arm 17, a first diameter D 1 and an initial penetration depth h 1 of the saw blade used, a second main cut with a second main cutting angle α 2 of the saw arm 17, a second diameter D 2 and a second penetration depth h 2 of the saw blade used and a third main cut with a third main cutting angle α 3 of the saw arm 17, a third diameter D 3 and a third penetration depth h 3 of the saw blade used.

[0066] In the exemplary embodiment, the first, second and third main cuts are carried out by the saw blade 16 with the saw blade diameter D and by the blade guard 21 with the blade guard width B. The diameters D 1 , D 2 , D 3 of the main cuts correspond to the saw blade diameter D of the saw blade 16, and the widths B 1 , B 2 , B 3 of the main cuts also correspond to the blade guard width B of the blade guard 21.

[0067] The main cuts are performed in the method according to the invention with a saw arm 17 that is arranged alternately in a pulling and pushing position. The pulling arrangement of the saw arm 17 enables stable guidance of the saw blade during processing and a narrow cutting gap. A separating cut in which the saw arm 17 is arranged alternately in a pulling and pushing position has the advantage that the downtime required for positioning the saw head 14 and pivoting the saw arm 17 is reduced compared to processing with a saw arm 17 arranged exclusively in a pulling position. In the exemplary embodiment of the FIGN. 5A-K During the first main cut and the third main cut, the saw head 14 is moved in the positive feed direction 56 with the saw arm 17 arranged in a pulling motion; during the intermediate second main cut, the saw head 14 is moved in the negative feed direction 57 with the saw arm 17 arranged in a pushing motion. The saw arm 17 is arranged in the negative rotation direction 54 in each of the three main cuts.

[0068] The processing of the separating cut begins at the first end point E 1 . After the start of the method according to the invention, the saw head 14 is moved to a start position X Start positioned in which the pivot axis 23 is at a distance of √[h 1 · (D 1 - h 1 )] - δ · sin(-α 1 ) from the first end point E 1 , where h 1 = h(-α 1 , D 1 ) = D 1 / 2 - Δ - δ · cos(-α 1 ) denotes the penetration depth of the saw blade used into the workpiece 24 at the negative first main cutting angle -α 1 with the first diameter D 1 , which corresponds to the saw blade diameter D. In the start position X Start, the saw arm 17 is pivoted from the basic position at 0° in the negative direction of rotation 54 into the negative first main cutting angle -α 1 . After the pivoting movement into the negative first main cutting angle -α 1 , the first blade guard edge 71 of the blade guard 21 borders on the obstacle at the first end point E 1 . Subsequently, the saw head 14 is moved with the saw arm 17 inclined at the negative first main cutting angle -α 1 and the rotating saw blade 16 in the positive feed direction 56 ( FIG. 5A During the feed movement, the position of the saw head 14 is regularly measured by the displacement sensor 33.

[0069] The feed movement of the saw head 14 is stopped when the pivot axis 23 has a distance from the second end point E 2 of √[h2 · (D 2 - h 2 )] + δ · sin(-α 2 ), where h 2 = h(-α 2 , D 2 ) = D 2 / 2 - Δ - δ · cos(-α 2 ) denotes the penetration depth of the saw blade used into the workpiece 24 at the negative second main cutting angle -α 2 with the second diameter D 2 , which corresponds to the saw blade diameter D ( FIG. 5B ). In this position, the saw arm 17 is pivoted from the negative first main cutting angle -α 1 to the negative second main cutting angle -α 2 ( FIG. 5C ). When positioning in FIG. 5B the distance is set so that the second upper exit point 59 of the saw blade 16 facing the second end point E 2 coincides with the second end point E 2 after the pivoting movement of the saw arm 17 into the negative second main cutting angle -α 2 .

[0070] The saw head 14 is moved in the negative feed direction 57 towards the first end point E 1, whereby the position of the saw head 14 is regularly measured by the displacement sensor 33 during the feed movement ( FIG. 5D ). The pivoting movement of the saw arm 17 from the negative second main cutting angle -α 2 to the negative third main cutting angle -α 3 takes place in the embodiment in two steps with a first intermediate angle -β 1 Performing the pivoting movement of the saw arm 17 in several steps with an intermediate angle is not part of the method according to the invention. Dividing the pivoting movement into at least two steps reduces the risk of polishing of the saw blade 16. A smaller pivot angle results in a reduction in the arc length of the saw blade that engages the workpiece.

[0071] The feed movement of the saw head 14 during the second main cut in FIG. 5D is stopped when the pivot axis 23 is at a distance of B / 2 - δ · sin(-β 1 ) from the first end point E 1 , when the first intermediate angle -β 1 is less than -90°. Since the pivoting movement takes place at the obstacle E 1 and the first intermediate angle -β 1 in the exemplary embodiment is greater than -90°, it is not possible to position the saw head 14 such that the second blade protection edge 72 borders the obstacle E 1 after the pivoting movement into the first intermediate angle -β 1 . The positioning of the saw head 14 takes place by means of the critical angle α krit of -90° and the saw arm 17 is then pivoted into the first intermediate angle -β 1 ( FIG. 5E ). At the critical angle α crit of -90°, the swivel axis 23 has a distance of B.2 / 2 - δ · sin(-90°) = B.2 / 2 + δ from the first end point E 1. The critical angle of -90° must be taken into account, since the first end point E 1 must not be exceeded during the swivel movement.

[0072] In the exemplary embodiment, the pivoting movement from the negative first main cutting angle -α 1 to the negative second main cutting angle -α 2 was carried out in one step, and the pivoting movement from the negative second main cutting angle -α 2 to the negative third main cutting angle -α 3 was carried out in two steps. Alternatively, the pivoting movement to the negative second main cutting angle -α 2 can be carried out in several steps, or the pivoting movement to the negative third main cutting angle -α 3 can be carried out in one step. The decision as to how many steps are required for the pivoting movement depends, among other things, on the specification of the saw blade, the hardness of the material, and the power and torque of the saw blade drive motor. The intermediate angles can be set by the operator, or the control unit of the wall sawing system can set the intermediate angles depending on various boundary conditions.For the separating cut, the main cutting angles of the main cuts and possible intermediate angles represent an input variable that is used to control the wall saw.

[0073] After the swivel movement of the saw arm 17 into the first intermediate angle -β 1 , the saw blade 16 is cut free. For this purpose, the saw head 14 with the saw arm 17 inclined at the first intermediate angle -β 1 and the rotating saw blade 16 is moved in the positive feed direction 56 by a path length of √[h 3 · (D 3 - h 3 )] ( FIG. 5F ), where h 3 = h(-α 3 , D 3 ) = D 3 / 2 - Δ - δ · cos(-180°) = D 3 / 2 - Δ + δ denotes the penetration depth of the saw blade 16 into the workpiece 24 at the negative third main cutting angle -α 3 with the third diameter D 3 , which corresponds to the saw blade diameter D. After free cutting, the saw head 14 is positioned by means of the critical angle α krit of -90° ( FIG. 5G ) and the saw arm 17 is then pivoted from the first intermediate angle -β 1 into the negative third main cutting angle -α 3 ( FIG. 5H ).

[0074] The third main cut represents the last main cut of the cutting sequence, and before processing the last main cut, corner machining of the first end point E 1 is carried out, which is not part of the method according to the invention. For corner machining, the saw head 14 is moved with the saw arm 17 inclined at -α 3 in the negative feed direction 57 until the pivot axis 23 is at a distance of from the first end point E 1 and the first blade guard edge 71 of the blade guard 21 borders the obstacle at the first end point E 1 ( FIG. 5I ). Corner machining of the first end point E 1 can be improved if the blade guard 21 is removed and corner machining is performed without the blade guard. Without the blade guard, the saw head 14 is moved in the negative feed direction 57 with the saw arm 17 inclined at -α 3 until the first saw blade edge 61 of the saw blade 16 coincides with the first end point E 1.

[0075] In the case of hard materials of the workpiece 24 or low-performance drive motors 18, the corner machining at the obstacle E 1 can also be carried out in several steps with intermediate angles; corner machining with intermediate angles is not part of the method according to the invention. For corner machining with intermediate angles, the saw arm 17 is moved to an initial position after the pivoting movement into the third main cutting angle -α 3 and, in the initial position, is pivoted to the first intermediate angle. With the saw arm 17 inclined at the first intermediate angle, the saw head 14 is moved in the negative feed direction 57 until the first blade protection edge 71 borders the obstacle E 1. The saw head 14 is then returned to the initial position, the saw arm 17 is pivoted to the next intermediate angle, and the saw head 14 with the inclined saw arm 17 is moved in the negative feed direction 57 until the first blade protection edge 71 borders the obstacle E 1.These process steps are repeated until the saw head 14, with the saw arm 17 inclined at the third main cutting angle -α 3 , is arranged in a position such that the first blade guard edge 71 is adjacent to the obstacle E 1 . Corner machining in several intermediate steps can also be carried out without the blade guard 21.

[0076] After corner machining of the first end point E 1, the third main cut is carried out with the saw arm 17 inclined at the negative third main cutting angle -α 3 in the positive feed direction 56 ( FIG. 5J ). The feed movement of the saw head 14 is stopped when the pivot axis 23 is at a distance of √[h 3 · (D 3 - h 3 )] + δ · sin(-α 3 ) from the second end point E 2 , where h 3 = h(-α 3 , D 3 ) = D 3 / 2 - Δ - δ · cos(-α 3 ) denotes the penetration depth of the saw blade into the workpiece 24 at the negative third main cutting angle -α 3 with the third diameter D 3 , which corresponds to the saw blade diameter D.

[0077] In the example of FIGN. 5A-K After the third main cut, the corner of the second end point E 2 ( FIG. 5K), which is not part of the method according to the invention. In the case of hard materials of the workpiece 24 or low-performance drive motors 18, the corner machining at the second end point E 2 can also be carried out in several steps with intermediate angles; carrying out the pivoting movement of the saw arm 17 in several steps with intermediate angles is not part of the method according to the invention. For corner machining with intermediate angles, the saw arm 17 is moved to an initial position after the end of the third main cut and is pivoted to the first intermediate angle in the initial position. The initial position is calculated such that the pivoting movement into all intermediate angles of the corner machining takes place before the second end point E 2 and the second end point E 2 is not exceeded.With the saw arm 17 inclined at the first intermediate angle, the saw head 14 is moved in the positive feed direction 56 until the second upper exit point 59 of the saw blade 16 has reached a final position, wherein the second upper end point 59 in the final position has a distance from the second end point E 2 of √[h 3 · (D - h 3 )) - √(Δh · (D - Δh)]. Where Δh = h 3 - T denotes the difference between the penetration depth h 3 and the final depth T and h 3 = h(-α 3 , D) = D / 2 - Δ - δ · cos(-α 3 ) denotes the penetration depth of the saw blade 16 into the workpiece 24 at the negative third pivot angle -α 3 . The saw head 14 is then returned to the starting position, the saw arm 17 is moved into the next intermediate angle and the saw head 14 with the inclined saw arm 17 is moved into the end position in the positive feed direction 56.These process steps are repeated until the saw head 14 is arranged in the final position with the saw arm 17 inclined at the negative third main cutting angle -α 3 .

Claims

1. Method for controlling a wall-saw system (10) comprising a guide rail (11) and comprising a wall saw (12) with a saw head (14), with a motorized feed unit (15) which displaces the saw head (14) parallel to a feed direction (28) along the guide rail (11), with at least one saw blade (16) which is fastened to a saw arm (17), pivotable about a pivot axis (23), of the saw head (14) and is driven about an axis of rotation (19), and with at least one releasable blade guard (21), surrounding the saw blade (16), when producing a separating cut (51) of end depth (T) in a workpiece (24) of workpiece thickness (d) between a first end point (E1) and a second end point (E2), comprising: ▪ before the start of a machining of the separating cut that is controlled by a control unit (29) of the wall saw (12), at least the saw-blade diameter (D) of the at least one saw blade (16), the positions of the first and second end points (E1, E2) in the feed direction (28), the end depth (T) of the separating cut and a main-cut sequence of main cuts are determined, wherein the main-cut sequence comprises at least a first main cut with a first main-cut angle (α1) of the saw arm (17) and a first diameter (D1) of the saw blade used during the first main cut and a following second main cut with a second main-cut angle (α2) of the saw arm (17) and a second diameter (D2) of the saw blade used during the second main cut, ▪ during the machining controlled by the control unit (29) - the saw arm (17) is arranged at the negative first main-cut angle (-α1) in a negative direction of rotation (54), and - the saw head (14) is moved in a positive feed direction (56) in the direction of the second end point (E2) during the first main cut, wherein the saw arm (17) arranged at the negative first main-cut angle (-α1) is in a pulling arrangement, characterized in that, before the start of the machining controlled by the control unit (29), in addition a saw-arm length (δ) of the saw arm (17), which is defined as a distance between the pivot axis (23) of the saw arm (17) and the axis of rotation (19) of the saw blade (16), a distance (Δ) between the pivot axis (23) and the top side (53) of the workpiece (24), a first width (B1) for a blade guard (21) used during the first main cut and a second width (B2) for a blade guard (21) used during the second main cut are determined, wherein the first and second widths (B1, B2) are each made up of a first distance (B1a, B2a) of the axis of rotation (19) from the first blade-guard edge (71) and a second distance (B1b, B2b) of the axis of rotation (19) from the second blade-guard edge (72), and the saw head (14) is stopped during the machining controlled by the control unit (29) in a position in which a pivoting movement of the saw arm (17) into the negative second main-cut angle (-α2) takes place, wherein, after the pivoting movement of the saw arm (17) into the negative second main-cut angle (-α2), a second boundary (59, 62, 72), facing towards the second end point (E2), of the wall saw (12) coincides with the second end point (E2), wherein the second boundary (59, 62, 72) of the wall saw (12) is formed by a second upper exit point (59), facing towards the second end point (E2), of the used saw blade at a top side (53) of the workpiece (24) if the second end point (E2) constitutes a free end point without an obstacle, by a second saw-blade edge (62), facing towards the second end point (E2), of the used saw blade if the second end point (E2) constitutes an obstacle and the machining takes place without a blade guard, and by a second blade-guard edge (72), facing towards the second end point (E2), of the used blade guard if the second end point (E2) constitutes an obstacle and the machining takes place with a blade guard.

2. Method according to Claim 1, characterized in that, after the pivoting movement of the saw arm (17) into the negative second main-cut angle (-α2), the second upper exit point (59) of the used saw blade coincides with the second end point (E2) if the pivot axis (23) is at a distance of √[h2 · (D2 - h2)] + δ · sin(-α2) from the second end point (E2), where h2 = h(-α2, D2) = D2 / 2 - Δ - δ · cos(-α2) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative second main-cut angle (-α2) with the second diameter (D2), the second saw-blade edge (62) of the used saw blade coincides with the second end point (E2) if the pivot axis (23) is at a distance of D2 / 2 + δ · sin(-α2) from the second end point (E2), and the second blade-guard edge (72) of the used blade guard coincides with the second end point (E2) if the pivot axis (23) is at a distance of B2b + δ · sin(-α2) from the second end point (E2).

3. Method according to either of Claims 1 to 2, characterized in that the second main cut constitutes the last main cut of the main-cut sequence and the wall saw (12) is moved into an end position.

4. Method according to Claim 3, characterized in that the saw head (14) is moved in such a way that a first boundary (58, 61, 71), facing towards the first end point (E1), of the wall saw (12) coincides with the first end point (E1), wherein the first boundary (58, 61, 71) of the wall saw (12) is formed by a first upper exit point (58), facing towards the first end point (E1), of the used saw blade at the top side (53) of the workpiece (24) if the first end point (E1) constitutes a free end point without an obstacle, by a first saw-blade edge (61), facing towards the first end point (E1), of the used saw blade if the first end point (E1) constitutes an obstacle and the machining takes place without a blade guard, and by a first blade-guard edge (71), facing towards the first end point (E1), of the used blade guard if the first end point (E1) constitutes an obstacle and the machining takes place with a blade guard.

5. Method according to Claim 4, characterized in that the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h2 · (D2 - h2)] - δ · sin(-α2) from the first end point (E1), where h2 = h(-α2, D2) = D2 / 2 - Δ - δ · cos(-α2) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative second main-cut angle (-α2) with the second diameter (D2), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D2 / 2 - δ · sin(-α2) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B2a - δ · sin(-α2) from the first end point (E1).

6. Method according to either of Claims 1 to 2, characterized in that the main-cut sequence has a third main cut, to be carried out after the second main cut, with a third main-cut angle (α3) of the saw arm (17), a third diameter (D3) of the used saw blade and a third width (B3) of the used blade guard with a first and a second distance (B3a, B3b) from the blade-guard edges, wherein, with the third main cut, the saw arm (17) is arranged in a pulling arrangement and the saw head (14) is moved in the positive feed direction (56).

7. Method according to Claim 6, characterized in that, during the machining controlled by the control unit (29), the saw head (14) is moved in such a way that, after the pivoting movement of the saw arm (17) into the negative third main-cut angle (-α3), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first boundary (58, 61, 71) is formed by the first upper exit point (58) of the used saw blade if the first end point (E1) constitutes a free end point without an obstacle, by the first saw-blade edge (61) of the used saw blade if the first end point (E1) constitutes an obstacle and the machining takes place without a blade guard, and by the first blade-guard edge (71) of the used blade guard if the first end point (E1) constitutes an obstacle and the machining takes place with a blade guard.

8. Method according to Claim 7, characterized in that the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h3 · (D3 - h3)] - δ · sin(-α3) from the first end point (E1), where h3 = h(-α3, D3) = D3 / 2 - Δ - δ · cos(-α3) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative third main-cut angle (-α3) with the third diameter (D3), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D3 / 2 - δ · sin(-α3) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B3a - δ · sin(-α3) from the first end point (E1).

9. Method according to one of Claims 1 to 8, characterized in that the first and second main cuts are carried out using a saw blade (16) and a blade guard (21).

10. Method according to one of Claims 1 to 8, characterized in that the first main cut is carried out by a first saw blade (16.1) and a first blade guard (21.1), wherein the first saw blade (16.1) has a first saw-blade diameter (D.1) and the first blade guard (21.1) has a first blade-guard width (B.1), and the second main cut is carried out using a second saw blade (16.2) and a second blade guard (21.2), wherein the second saw blade (16.2) has a second saw-blade diameter (D.2) and the second blade guard (21.2) has a second blade-guard width (B.2).

11. Method according to one of Claims 1 to 10, characterized in that the first main cut of the main-cut sequence constitutes a preliminary cut and, after the start of the machining controlled by the control unit (29), the saw head (14) is positioned in a starting position (XStart) parallel to the feed direction (28), wherein, in the starting position (XStart), after the pivoting movement into the negative first main-cut angle (-α1), the first boundary (58, 61, 71), facing towards the first end point (E1), of the wall saw (12) coincides with the first end point (E1), wherein the first boundary (58, 61, 71) is formed by the first upper exit point (58) of the used saw blade if the first end point (E1) constitutes a free end point without an obstacle, by the first saw-blade edge (61) of the used saw blade if the first end point (E1) constitutes an obstacle and the machining takes place without a blade guard, and by the first blade-guard edge (71) of the used blade guard if the first end point (E1) constitutes an obstacle and the machining takes place with a blade guard.

12. Method according to Claim 11, characterized in that, in the starting position (XStart), the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h1 · (D1 - h1)] - δ · sin(-α1) from the first end point (E1), where h1 = h(-α1, D1) = D1 / 2 - Δ - δ · cos(-α1) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative first main-cut angle (-α1) with the first diameter (D1), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D1 / 2 - δ · sin(-α1) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B1a - δ · sin(-α1) from the first end point (E1).

13. Method according to one of Claims 1 to 10, characterized in that the main-cut sequence comprises a preliminary cut, to be carried out before the first main cut, with a zeroth main-cut angle (α0) of the saw arm (17), a zeroth diameter (D0) and a zeroth width (B0) with a first and a second distance (B0a, B0b) from the blade-guard edges, wherein, with the preliminary cut, the saw arm (17) is arranged in a pulling arrangement and the saw head (14) is moved in the negative feed direction (57).

14. Method according to Claim 13, characterized in that, after the start of the machining controlled by the control unit (29), the saw head (14) is positioned in a starting position (XStart) parallel to the feed direction (28) for the preliminary cut, wherein, in the starting position (XStart), the second boundary (59, 62, 72), facing the second end point (E2), of the wall saw (12) coincides with the second end point (E2) after the pivoting movement into the positive zeroth main-cut angle (+α0).

15. Method according to Claim 14, characterized in that, after the pivoting movement of the saw arm (17) into the positive zeroth main-cut angle (+α0), the second upper exit point (58) of the used saw blade coincides with the second end point (E2) if the pivot axis (23) is at a distance of √[h0 · (D0 - h0)] + δ · sin(+α0) from the second end point (E2), where h0 = h(+α0, D0) = D0 / 2 - Δ - δ · cos(+αo) denotes the penetration depth of the used saw blade into the workpiece (24) at the positive zeroth main-cut angle (+α0) with the zeroth diameter (D0), the second saw-blade edge (62) of the used saw blade coincides with the second end point (E2) if the pivot axis (23) is at a distance of D0 / 2 + δ · sin(+α0) from the second end point (E2), and the second blade-guard edge (72) of the used blade guard coincides with the second end point (E2) if the pivot axis (23) is at a distance of B0b + δ · sin(+α0) from the second end point (E2).

16. Method according to Claim 15, characterized in that, during the controlled machining, the saw head (14) is stopped in the positive feed direction (56) if the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first boundary (58, 61, 71) of the wall saw (12) is formed by the first upper exit point (58) of the used saw blade at the top side (53) of the workpiece (24) if the first end point (E1) constitutes a free end point without an obstacle, by the first saw-blade edge (61) of the used saw blade if the first end point (E1) constitutes an obstacle and the machining takes place without a blade guard, and by the first blade-guard edge (71) of the used blade guard if the first end point (E1) constitutes an obstacle and the machining takes place with a blade guard.

17. Method according to Claim 16, characterized in that the saw head (14) is positioned in the positive feed direction (56) in such a manner that, after the pivoting movement of the saw arm (17) into the negative first main-cut angle (-α1), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h1 · (D1 - h1)] + δ · sin(-α1) from the first end point (E1), where h1 = h(-α1, D1) = D1 / 2 - Δ - δ · cos(-α1) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative first main-cut angle (-α1) with the first diameter (D1), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D1 / 2 + δ · sin(-α1) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B1a + δ · sin(-α1) from the first end point (E1).

18. Method according to Claim 15, characterized in that the saw head (14) is moved in such a way that, after the pivoting movement of the saw arm (17) into the negative zeroth main-cut angle (-α0), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h0 · (D0 - h0)] - δ · sin(- a0) from the first end point (E1), where h0 = h(-α0, D0) = D0 / 2 - Δ - δ · cos(-α0) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative zeroth main-cut angle (-a0) with the zeroth diameter (D0), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D0 / 2 - δ · sin(-α0) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B0a - δ · sin(-a0) from the first end point (E1).

19. Method according to Claim 18, characterized in that the saw head (14) is moved by a travel length of at least 2δ · |sin(-α0)| in the positive feed direction (56), and the saw head (14) is subsequently positioned in such a way that, after the pivoting movement of the saw arm (17) into the negative first main-cut angle (-α1), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h1 · (D1 - h1)] - δ · sin(-α1) from the first end point (E1), where h1 = h(-α1, D1) = D1 / 2 - Δ - δ · cos(-α1) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative first main-cut angle (-α1) with the first diameter (D1), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D1 / 2 - δ · sin(-α1) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B1a - δ · sin(-α1) from the first end point (E1).

20. Method according to Claim 18, characterized in that the saw head (14) is moved in the positive feed direction (56) in such a way that, after the pivoting movement of the saw arm (17) into the negative first main-cut angle (-α1), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h1 · (D1 - h1)] - δ · sin(-α1) from the first end point (E1), where h1 = h(-α1, D1) = D1 / 2 - Δ - δ · cos(-α1) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative first main-cut angle (-α1) with the first diameter (D1), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D1 / 2 - δ · sin(-α1) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B1a - δ · sin(-α1) from the first end point (E1).

21. Method according to Claim 16, characterized in that the saw head (14) is moved in such a way that, after the pivoting movement of the saw arm (17) into the negative first main-cut angle (-α1), the first boundary (58, 61, 71) of the wall saw (12) coincides with the first end point (E1), wherein the first upper exit point (58) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of √[h1 · (D1 - h1)] - δ · sin(-α1) from the first end point (E1) in the feed direction (28), where h1 = h(-α1, D1) = D1 / 2 - Δ - δ · cos(-α1) denotes the penetration depth of the used saw blade into the workpiece (24) at the negative first main-cut angle (-α1) with the first diameter (D1), the first saw-blade edge (61) of the used saw blade coincides with the first end point (E1) if the pivot axis (23) is at a distance of D1 / 2 - δ · sin(-α1) from the first end point (E1), and the first blade-guard edge (71) of the used blade guard coincides with the first end point (E1) if the pivot axis (23) is at a distance of B1a - δ · sin(-α1) from the first end point (E1).