Patent Application
20180169898
The present invention relates to a method for controlling a wall saw system during the creation of a separation cut.
A method is known from EP 1 693 173 B1 for controlling a wall saw system during the creation of a separation cut in a workpiece between a first end point and a second end point. The wall saw system, comprises a guide rail and a wall saw with a saw head, a motor-driven feed unit that moves the saw head parallel to a feed direction along the guide rail, and at least one saw blade attached to a saw arm of the saw head and driven by a drive motor about an axis of rotation. The saw arm is pivotable by means of a pivoting motor about a pivot axis. By a pivoting movement of the saw arm about the pivot axis, the penetration depth is changed in the workpiece. The motor-driven feed unit comprises a guide carriage and a feed motor, wherein the saw head is mounted on the guide carriage and moved via the feeding motor along the guide rail. To monitor the wall saw system a sensor device is provided with a pivot angle sensor and a displacement sensor. The pivot angle sensor measures the present pivot angle of the saw arm and the displacement sensor measures the actual position of the saw head on the guide rail. The measured values for the current pivot angle of the saw arm and the actual position of the saw head are regularly sent to a control unit of the wall saw.
The known method for controlling a wall saw system is divided into a preparation part and processing of the separation cut. In the preparation part the operator sets at least the saw blade diameter of the saw blade, the positions of the first and second end point in the feed direction and the final depth of the separation cut; other parameters can be the material of the workpiece to be machined and the dimensions of embedded rebar. From the parameters entered, the control unit determines an appropriate main cutting sequence of main cuts for the separation cut, wherein the main cutting sequence comprises at least a first main cut having a first main cutting angle of the saw arm and a first diameter of the saw blade used, and a following second main cut with a second main cutting angle of the saw arm and a first diameter of the saw blade used.
The known method for controlling a wall saw system discloses no details on how the exchange of the saw blade and blade guard is done during the controlled processing of the separation cut.
The object of the present invention is to develop a method for controlling a wall saw system with high processing quality, in which the exchange of a saw blade and a blade guard is integrated into the controlled processing of a separation cut.
This object is achieved according to the invention in the method for controlling a wall saw system mentioned by the features of the independent claim. Advantageous developments are specified in the dependent claims.
The invention is characterized in that after processing of the separation cut with the first blade, the controlled processing of the separation cut is interrupted by the control unit and the wall saw is moved by the control unit into a park position.
By integrating a saw blade change and blade guard change in the controlled processing with the control unit, all boundary conditions can be taken into account by the control unit and the wall saw can be positioned in a park position in which all actions can be performed by the saw blade and blade guard exchange. When changing the saw blade from a first blade to a second blade and the blade guard from a first blade guard to a second blade guard the following are to be considered as boundary conditions:
Preferably the wall saw after the exchange of the saw blade from the first to the second saw blade and the resumption of the controlled processing by the control unit is positioned in a resumption position. If the control unit in addition to the park position determines a resumption position, after the interruption the wall saw can be moved by the operator from the park position by means of the motor-driven feed unit along the guide rail. The possibility of being able to move the wall saw from the park position is advantageous for vertical or diagonal separation cuts in a wall in which the park position is arranged above a manageable mounting position. For dismounting the first equipment (first saw blade and first blade guard) and mounting the second equipment (second saw blade and second blade guard), the operator moves the saw head into a mounting position suitable for him/her. After the resumption, the control unit with the aid of the displacement sensor checks the current position of the wall saw. If the current position deviates from the resumption position, the wall saw is positioned in the resumption position.
In a preferred embodiment, before the start of the processing controlled by the control unit additionally a length of the saw arm is determined, defined as the distance between the pivot axis of the saw arm and the axis of rotation of the saw blade, and the distance between the pivot axis of the saw arm and an upper side of the workpiece. For a controlled processing of the separation cut, the control unit must know various parameters. These include the saw arm length, which represents a fixed device-specific size of the wall saw, and the vertical distance between the pivot axis and the surface of the workpiece, which besides the geometry of the wall saw also depends on the geometry of the guide rail used.
In the calculation of the park position for an exchange of the saw blade and/or blade guard, a distinction must be made: the exchange takes place at a free end point without barrier (first embodiment), the saw blade is exchanged at a barrier without blade guard (second embodiment), the saw blade and blade guard are exchanged at a barrier for the second saw blade without blade protection (third embodiment), and the saw blade and blade guard are exchanged at a barrier for a second saw blade and second blade guard (fourth embodiment).
In the first embodiment, the second end point is a free end point without barrier and the second diameter of the second saw blade set before the start is used for calculation of the first park position and the resumption position corresponding to the first park position. The pivot axis in the first park position has a distance to the second end point of √[h2(D.2−h2)]+δ·sin(±α2), where h2=h(±α2, D.2)=D.2/2−Δ−δ·cos(±α2) designates the penetration depth of the second saw blade into the workpiece at the second main cutting angle with the preset second saw blade diameter.
As an alternative to the preset second saw blade diameter, the second saw blade diameter of the second saw blade is adjustable between a maximum second saw blade diameter and a minimum second saw blade diameter, wherein the maximum second saw blade diameter is used for calculating a second park position. With a saw blade, its diameter changes because of wear in the processing and declines over time, where the difference between the maximum and minimum second saw blade diameters corresponds to the height of the cutting segments.
The pivot axis in the second park position has a distance to the second end point of √[h2.max(Dmax.2−h2.max)]+δ·sin(±α2), where h2.max=hmax(±α2, Dmax.2)=Dmax.2/2−Δ−δ·cos(±α2) designates the maximum penetration depth of the second saw blade into the workpiece at the second main cutting angle with the maximum second saw blade diameter. Calculating the second park position with the maximum second saw blade diameter assures that the second park position is suitable for all actual saw blade diameters of the second saw blade.
After the resumption of the controlled processing the wall saw is positioned in a resumption position corresponding to the second park position. The resumption of the controlled processing in the second park position is possible for all actual saw blade diameters of the second saw blade; however, it has an inaccuracy in the positioning.
Preferably, before the resumption of the controlled processing the actual second saw blade diameter of the second saw blade is entered and used for calculating a resumption position. In the recalculated resumption position the pivot axis has a distance to the second end point of √[h2(Dreal.2−h2)]+δ·sin(±α2), where h2=h(±α2, Dreal.2)=Dreal.2/2−Δ−δ·cos(±α2) designates the penetration, depth of the second saw blade into the workpiece at the second main cutting angle with the actual second saw blade diameter. The entry of the actual second saw blade diameter enables an exact control of the wall saw. The park position is calculated such that any permissible saw blade diameter for the second saw blade can be mounted. Through the calculation of the resumption position with the actual second saw blade diameter, the control of the wall saw can be done through the upper exit point of the saw blade.
In the further embodiments, the second end point is defined as a barrier and before the start of the controlled processing a mounting distance is additionally established, wherein the mounting distance is additionally used for calculating a third to fifth park position. The mounting distance assures a sufficient distance for the operator between the barrier and the saw blade and between the barrier and the blade guard to engage the saw blade and blade guard.
The control unit calculates different park positions depending on the boundary conditions of the processing. In the third park position the first and second saw blades are used without blade guards. In the fourth park position, the first saw blade is surrounded by the first blade guard and the processing is done with the second saw blade without blade guard. In the fifth park position, the change occurs from the first saw blade with first blade guard to the second saw blade with second blade guard. The park positions must meet the four boundary conditions (dismounting, mounting, pivoting out and pivoting in) and are dependent on the first main cutting angle of the first main cut and the second main cutting angle of the second main cut.
In the third park position the processing occurs with the first and second saw blades without blade guards. For the main cutting angle, three angle areas of −180° to 0°, 0° to 90° and 90° to 180° must be distinguished, thus yielding a total of nine different distances for the third park position.
In the first angle area, the saw arm before the interruption of the controlled processing is arranged at a negative first main cutting angle between −180° and 0° and the pivot axis in the third park position has a distance to the second end point of maximum value of [D1/2+Δmount, D2/2+Δmount] for −180°≤−α2≤0°, maximum value of [(D1/2+Δmount, D2/2+Δmount, D2/2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [D1/2+Δmount, D2/2+Δmount, D2/2+δ·sin(90°)] for 90°<α2≤180°. For all negative main cutting angles the displacement δ·sin(−α1) is negative, and therefore in principle applies D1/2+δ·sin(−α1)<D1/2+Δmount. If the second diameter D2 is greater than the first diameter D1, in principle applies D1/2+Δmount<D2/2+Δmount.
In the second angle area, the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between −0° and 90° and the pivot axis in the third park position has a distance to the second end point of maximum value of [D1/2+Δmount, D2/2+Δmount, D1/2+δ·sin(α1)] for −180°≤−α2≤0°, maximum value of D1/2+Δmount, D2/2+Δmount, D1/2+δ·sin(α1), D2/2+δ·sin(−α2)] for 0°<α2≤90° and maximum value of [D1/2+Δmount, D2/2+Δmount, D2/2+δ·sin(90°)] for 90°<α2≤180°. For all negative second main cutting angles the displacement δ·sin(−α2) is negative, and therefore in principle applies D2/2+δ·sin(−α2)<D2/2+Δmount.
In the third angle area, the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between 90° and 180° and the pivot axis in the third park position has a distance to the second end point of maximum value of [D1/2+Δmount, D2/2+Δmount, D1/2+δ·sin(90°)] for −180°≤−α2≤0° and maximum value of [D1/2+Δmount, D2/2+Δmount, D2/2+δ·sin(90°)] for 90°<α2≤180°.
In a first preferred embodiment, for calculating the third park position for the first diameter of the first main cut the preset first saw blade diameter of the first saw blade and for the second diameter of the second main cut the preset second saw blade diameter of the second saw blade are used. Preferably the wall saw after the resumption of the controlled processing by the control unit is positioned in a resumption position corresponding to the third park position.
In a second preferred embodiment, the second saw blade diameter between a maximum second saw blade diameter and a minimum second saw blade diameter is adjustable, and for calculating the park position for the second diameter of the second main cut the maximum second saw blade diameter is used. Calculating the park position with the maximum second saw blade diameter assures that the park position is suitable for all actual saw blade diameters of the second saw blade.
The wall saw is either positioned in a resumption position corresponding to the park position or before the resumption of the controlled processing the actual second saw blade diameter of the second saw blade is entered and used for calculating a resumption position. The pivot axis in the resumption position has a distance to the second end point of Dreal.2/2 for −180°≤−α2≤0°, Dreal2/2+δ·sin(α2) for 0°≤α2≤90°, and Dreal2/2+δ·sin(90°) for 90°≤α2≤180°.
In the third embodiment, before the start of the controlled processing for the first saw blade a first blade guard with a first blade guard width is determined, wherein the first blade guard width is compiled from a first distance of the axis of rotation to the first blade guard edge and a second distance of the axis of rotation to the second blade guard edge, and the second distance is additionally used for calculating the fourth park position. In processing with the first blade guard, the fourth park position depends on the first and second main cutting angles. For the main cutting angles, three angle areas of −180° to 0°, 0° to 90°, and 90° to 180° are to be distinguished, yielding a total of nine different distances for the fourth park position.
In the first angle area the saw arm before the interruption of the controlled processing is arranged at a negative first main cutting angle between −180° and 0° and in the fourth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, D2/2+Δmount] for −180°≤−α2≤0°, maximum value of (Bb.1+Δmount, D2/2+Δmount, D2/2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, D2/2+Δmount, D2/2+δ·sin(90°)]<α2≤180°.
In the second angle area the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between 0° and 90° and in the fourth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(α1)] for −180°≤−α2≤0°, maximum value of (Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(α1), D2/2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(α1), D2/2+δ·sin(90°)] for 90°<α2≤180°.
In the third angle area the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between 90° and 180° and in the fourth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(90°)] for −180°≤−α2≤0°, maximum value of (Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(90°), D2/2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, D2/2+Δmount, Bb.1+δ·sin(90°)] for 90°<α2≤180°.
After the resumption of the controlled processing the wall saw is positioned in a resumption position corresponding to the fourth park position. In the resumption position the wall saw is pivoted to the second main cutting angle and the saw head is then moved in a negative feed direction counter to the positive feed direction in the direction of the first end point.
In the fourth embodiment, before the start of the controlled processing for the second saw blade a second blade guard with a second blade guard width is determined, wherein the second blade guard width is compiled from a first distance to the axis of rotation to the first blade guard edge and a second distance of the axis of rotation to the second blade guard edge, and the second distance is additionally used for calculating the fifth park position. In processing with the first and second blade guards, the fifth park position depends on the first and second main cutting angles. For the main cutting angles, three angle areas—negative main cutting angle, positive main cutting angle of 0° to 90°, and positive main cutting angle of 90° to 180°—are to be distinguished, yielding a total of nine different distances for the fifth park position.
In the first angle area the saw arm before the interruption of the controlled processing is arranged at a negative first main cutting angle between −180° and 0° and in the fifth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, Bb.2+Δmount] for −180°≤−α2≤0°, maximum value of (Bb.1+Δmount, Bb.2+Δmount, Bb.2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, Bb/2+Δmount, Bb/2+δ·sin(90°)] for 90°<α2≤180°.
In the second angle area the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between 0° and 90° and in the fifth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(α1)] for −180°≤−α2≤0°, maximum value of (Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(α1), Bb.2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(α1), Bb.2+δ·sin(90°)] for 90°<α2≤180°.
In the third angle area the saw arm before the interruption of the controlled processing is arranged at a positive first main cutting angle between 90° and 180° and in the fifth park position the pivot axis has a distance to the second end point of maximum value [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°)] for −180°≤−α2≤0°, maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°), Bb.2+δ·sin(α2)] for 0°<α2≤90° and maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°), Bb.2+δ·sin(90°)] for 90°<α2≤180°.
After the resumption of the controlled processing the wall saw is positioned in a resumption position corresponding to the fourth park position. In the resumption position the wall saw is pivoted to the second main cutting angle and the saw head is then moved in a negative feed direction counter to the positive feed direction in the direction of the first end point.
Embodiments of the invention are described below based on the drawings. These do not necessarily represent the embodiments to scale; instead, where helpful for the explanation the drawings are produced in schematic and/or slightly distorted form. Regarding additions to the teachings directly evident from the drawings, reference is made to the relevant prior art. It must be kept in mind that various modifications and changes to the form and detail of an embodiment can be made without deviating from the general idea of the invention. The invention's features disclosed in the description, drawings and claims can be essential both individually and in any combination for the development of the invention. In addition, all combinations of at least two of the features described in the description, drawings and/or claims fall within the framework of the invention. The general idea of the invention is not restricted to the exact shape or detail of the embodiments shown and described below or restricted to a subject matter that would be restricted compared to the subject matter claimed in the claims. Where dimension areas are given, values lying inside the given boundaries are also disclosed as limit values and can be used and claimed randomly. For the sake of simplicity, the same reference signs are used below for identical or similar parts or parts with identical or similar function.
To protect the operator, the saw blade 16 is surrounded by a blade guard 21, which is secured by means of a blade guard holder on the saw arm 17. The saw arm 17 is formed from a pivoting motor 22 to pivot about a pivot axis 23. The pivot angle α of the saw arm 17 determines with a blade diameter D of the saw blade 16, how deep the blade 16 dips into a workpiece 24 to be processed. The drive motor 18 and the pivoting motor 22 are arranged in a device housing 25. The motor-driven feed unit 15 comprises a guide carriage 26 and a feed motor 27 that in the embodiment is also arranged in the device housing 25. The saw head 14 is fixed on the guide carriage 26 and designed to be displaceable through the feed motor 27 along the guide rail 11 in a feed direction 28. In the device housing 25 in addition to the motors 19, 22, 27 a control unit 29 is arranged for controlling the saw head 14 and the motor-driven feed unit 15.
To monitor the wall saw system 10 and the processing procedure, a sensor device is provided with several sensor elements. A first sensor element 32 is designed as a pivot angle sensor and a second sensor element 33 as a displacement sensor. The pivot angle sensor 32 measures the current pivot 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 by the pivot angle sensor 32 and displacement sensor 33 to the control unit 29 and used for controlling the wall saw 12.
The remote control 13 comprises a device housing 35, an input device 36, a display device 37, and a control unit 38 that is arranged in the interior of the device housing 35. The control unit 38 converts the inputs of the input device 36 into control commands and data that are transmitted via a first communication link to the wall saw 12. The first communication link is configured as a wireless and cordless communication link 41 or a communications cable 42. The wireless and cordless communication link is formed in the embodiment as a radio link 41 created between a first radio unit 43 on the remote control 13 and a second radio unit 44 on the power tool 12.
Alternatively, the wireless and cordless communication link 41 can be in the form of an infrared, Bluetooth, WLAN or Wi-Fi connection.
The end point of a separation cut can be defined as free end point without barrier or as barrier. Both end points can be defined as free end points without barrier, both end points as barrier, or one end point as free end point and the other end point as barrier. An overcut can be allowed at a free end point without barrier. Through the overcut, at the end point the depth of cut reaches the final depth T of the separation cut. In the embodiment of FIGS, 2A, B the end points E1, E2 form free end points without barrier, wherein on the free first end point E1 an overcut is not permissible and on the second end point E2 there is an overcut.
The X positions of the first and second end points E1, E2 are determined in the embodiment by the entry of partial lengths. The distance between the mounting position X0 and t be first end point E1 determines a first partial length L1 and the distance between the mounting position X0 and the second end point E2 a second partial length. Alternatively, the X positions of the end points E1, E2 can be established by entering a partial length (L1 or L2) and a total length L as the distance between the end points E1, E2.
The separation cut 51 is produced in multiple partial cuts until the desired final depth T is reached. The partial cuts between the first and the second end points E1, E2 are defined as the main cut and the cutting sequence of the main cut as the main cutting sequence. At the end points of the separation cut an additional corner processing can be performed, which with a barrier is called barrier processing and with a free end point with overcut is called overcut processing.
The main cutting sequence can be determined by the operator, or the control unit of the wall saw system determines the main cutting sequence depending on several boundary conditions. Usually the first main cut, also called precut, is made with a reduced depth of cut and a reduced power of the drive motor to prevent a polishing of the saw blade. The remaining main cuts are normally done with the same depth of cut, but can also have different cut depths. The boundary conditions usually established by an operator include the cut depth of the precut, the power of the precut, and the maximum depth of cut of the remaining main cuts. The control unit can determine the main cutting sequence from these boundary conditions.
The main cuts of a separation cut are done with one saw blade diameter or with two or more saw blade diameters. If multiple saw blades are used, the processing usually starts with the smallest saw blade diameter. To be able to mount the saw blade 16 on the saw arm 17, in the basic position of saw arm 17 the saw blade 16 must be arranged above the workpiece 24. Whether this boundary condition is fulfilled depends on two device-specific sizes of the wall saw system 10: a perpendicular distance Δ between the pivot axis 23 of saw arm 17 and an upper side 53 of the workpiece 24; and the saw arm length δ of saw arm 17, defined as the distance between the axis of rotation 19 of saw blade 16 and the pivot axis 23 of saw arm 17. If the total of these two device-specific amounts is greater than half the saw blade diameter D/2, the saw blade 16 in the basic position is arranged above the workpiece 24. The saw arm length δ is a fixed device-specific amount of wall saw 12, whereas the perpendicular distance Δ between the pivot axis 23 and the surface 53 besides the geometry of wall saw 12 also depends on the geometry of the guide rail 11 used.
The saw blade 16 is fastened on a flange on saw arm 17 and in the saw operation is driven by drive motor 18 around the axis of rotation 19. In the basic position of saw arm 17, shown in
To protect the operator, during operation the saw blade 16 should be surrounded by blade guard 21. Wall saw 12 is operated either with blade guard 21 or without blade guard 21. For processing of the separation cut in the area of end points E1, E2, a dismounting of blade guard 21 can be provided. If different saw blade diameters are used for processing the separation cut, different blade guards with corresponding blade guard width are also used,
The maximum penetration depth of saw blade 16 into workpiece 24 is reached at a pivot angle of ±180°. The position of the axis of rotation 19 in the X direction and Y direction is shifted by the pivoting movement of saw arm 17 around pivot axis 23. The displacement of pivot axis 19 depends on the saw arm length δ and pivot axis α of saw arm 17. The displacement δx in the X direction is δ·sin(±α) and the displacement δy in the Y direction is δ·cos(±α).
The saw blade 16 produces in workpiece 24 a cutting edge in the shape of a circular segment with a height h and width b. The height h of the circular segment corresponds to the penetration depth of saw blade 16 into workpiece 24. The relationship D/2=h+Δ+δ·cos(α) applies for the penetration depth h, where D designates the saw blade diameter, h the penetration depth of saw blade 16, Δ the perpendicular distance between pivot axis 23 and upper side 53 of workpiece 24, δ the saw arm length and a the first pivot angle, and for the width b relationship b2=D/2·8h−4h2=4Dh−4h2=4h·(D−h) applies, where h designates the penetration depth of saw blade 16 into workpiece 24 and D the saw blade diameter.
The control of wall saw 12 during the separation cut depends on whether the end points are defined as barriers, and if there is a barrier whether the processing is done with blade guard 21 or without blade guard 21. With a free end point without barrier, the control of wall saw 12 in the inventive method occurs through upper exit points of saw blade 16 at upper side 53 of workpiece 24. The upper exit points of saw blade 16 can be calculated from the reference position XRef of pivot axis 23 in the X direction, displacement δx of axis of rotation 19 in the X direction, and width b. An upper exit point facing the first end point E1 is designated as first upper exit point 58, and an upper exit point facing the second end point E2 as second upper exit point 59. For the first upper exit point 58 applies X(58)=XRef+δx−b/2, and for the second upper exit point 59 applies X(59)=XRef+δx+b/2 with b=√[h·(D−h)] and h=h (α, D).
If the end points E1, E2 are defined as barriers, an overrun of the end points E1, E2 with wall saw 12 is not possible. In this case the control of wall saw 12 in the inventive method occurs through the reference position XRef of pivot axis 23 and the limit of wall saw 12. A distinction is made between a processing without blade guard 21 and a processing with blade guard 21.
The X positions of the first and second saw blade edges 61, 62 in the X direction can be calculated from the reference position XRef of pivot axis 23, displacement δx of axis of rotation 19 and saw blade diameter D.
The X positions of the first and second blade guard edges 71, 72 in the X direction can be calculated from the reference position XRef of pivot axis 23, displacement δx of axis of rotation 19 and blade guard width B.
For the first blade guard edge 71 applies X(71)=XRef+δ·sin(α)−Ba and for the second blade guard edge 72 applies X(72)=XRef+δ·sin(α)+Bb. FIG. 4B shows the wall saw 12 with the saw arm 17 inclined at positive swivel angle α(0° to +180°), and the mounted blade guard 21 of the blade guard width B. For the first blade guard edge 71 applies X(71)=Xref+δ·sin(α)−Ba and for the second blade guard edge 72 applies X(72)=XRef+δ·sin(α)+Bb.
The first upper exit point 58, the first blade edge 61 and the first blade edge guard 71 are summarized under the term “first limit”of wall saw 12 and the second upper exit point 59, the second blade edge 62 and the second blade guard edge 72 are summarized under the term “second limit.”
The processing of the separation is done with the help of the inventive method for controlling a wall saw system. The separation cut is made in a main cutting sequence of several main cuts until the desired final depth T is reached. The main cutting sequence comprises a precut (zeroed main cut) with a zeroed main cutting angle α0 of the saw arm 17, a zeroed diameter D0 and a zeroed penetration depth h0 of the saw blade used, a first main cut with a first main cutting the saw arm 17, a first diameter D1 and first penetration depth h1 of the saw blade used, a second main cut with a second main cutting angle α2 of the saw arm 17, a second diameter D2 and a second penetration depth h2 of the saw blade used, as well as a third main cut with a third main cutting angle α3 of the saw arm 17, a third diameter D3 and a third penetration depth h3 of the saw blade used.
The precut and the first main cut are made by a first saw blade 16.1 with a first saw blade diameter D.1 and a first blade guard 21.1 with a first blade guard width B.1. The zeroed diameter D0 of the precut and the first diameter D1 match the first saw blade diameter D.1, and the zeroed width B0 of the precut and the first width B1 of the first main cut match the first blade guard width B.1. The second main cut and the third main cut are made by a second saw blade 16.2 with a second saw blade diameter D.2 and a second blade guard 21.2 with a second blade guard width B.2. The second diameter D2 of the second main cut and the third diameter D3 of the third main cut match the second saw blade diameter D.2, and the second width B2 of the second main cut and the third width B3 of the third main cut match the second blade guard width B.2.
The main cuts of a separation cut are advantageously either done with a pulling saw arm 17 or the saw arm 17 is arranged alternatingly pulling and pushing. The pulling arrangement of saw arm 17 enables a stable guiding of the saw blade during the processing and a narrow kerf. A separation cut in which the saw arm is arranged alternatingly pulling and pushing has the advantage that the nonproductive times necessary for positioning the saw head 14 and pivoting the saw arm 17 are reduced.
In the embodiment of
Since the first blade guard 21.1 is mounted, the control of the wall saw 12 at the first end point E1 occurs through the first blade guard edge 71.1 of the first blade guard 21.1. The saw head 14 is stopped if the pivot axis 23 has a distance of B1/2−δ·sin(−α1) to the first end point E1. The first width B1 of the blade guard used corresponds to the first blade guard B.1 width of the first blade guard 21.1. The saw arm 17 is then rotated in the negative direction of rotation 54 at the negative first main cutting angle −α1 and the saw head 14 with the saw arm 17 inclined at −α1 is moved in the positive feed direction 56 (
The saw head 14 is moved in the positive feed direction 56 until that the pivot axis 23 has a distance of √[h1(D1−h1)]+δ·sin(−α1) to the second end point E2, where h1=h(−α1, D1 )=D1/2−Δ−δ·cos(−α1) designates the penetration depth of the first saw blade 16.1 into the workpiece 24 at the negative first main cutting angle −α1 with the first diameter D1, which corresponds to the first saw blade diameter D.1. The saw arm 17 is then pivoted in the positive direction of rotation 55 at the positive first main cutting angle α1 and the residual material removed.
To change the saw blade from, the first saw blade 16.1 to the second saw blade 16.2, saw head 14 is positioned in a park position and saw arm 17 is pivoted out from the workpiece 24, wherein saw arm 17 in the embodiment is pivoted into the basic position of 0° (
The park position should fulfill various boundary conditions. The first saw blade 16.1 and the first blade guard 21.1 can be dismounted in the park position. The second saw blade 16.2 and the second blade guard 21.2 can be mounted in the park position. Furthermore, the movement path to the positioning of saw head 14 for the second main cut should be as small as possible; ideally, the park position corresponds to the start position for the second main cut.
Since the second end point E2 is a free end point without barrier, the dismounting of the first saw blade 16.1 and first blade guard 21.1, as well as the mounting of the second saw blade 16.2 and second blade guard 21.2 are easily possible. In the park position shown in
After the mounting of the second saw blade 16.2 and second blade guard 21.2, as well as the resumption of the controlled processing, the wall saw 12 is positioned by the control unit 29 into a resumption position that corresponds to the park position. In calculating the park position the distance was set such that the second upper exit point 59.2 facing the second end point E2 of the second saw blade 16.2 after the rotation movement of saw arm 17 at the positive second main cutting angle α2 coincides with the second end point E2 (
In the resumption position, the saw arm 17 is rotated in the positive direction of rotation 55 at the positive second main cutting angle α2. The saw head 14 is moved with the saw arm 17 inclined at the second main cutting angle α2 and the rotating second saw blade 16.2 in the negative feed direction 57. The transition from the second main cut to the third main cut is done analogously to the transition from the precut to the first main cut with a complete removal of the residual material (
In practice, it is common when cutting a workpiece to perform the last main cut at the maximum pivot angle of the saw arm, in order to remove as much material in the region of the end points as possible. Without limiting the allowable maximum depth of cut the maximum pivot angle is ±180° and with restriction the allowable maximum depth of cut of the saw blade can be converted to a maximum pivot swivel angle. In the embodiment, the third main cut corresponds to the last main cut and is done at a third main cutting angle of −180°.
The positioning of saw head 14 for the third main cut at the maximum pivot angle of −180° is done by means of the critical angle αcrit of −90°. The critical angle of −90° must be taken into consideration since the first end point E1 may not exceed the pivot movement. The pivot axis 23 at the critical angle αcrit of −90°has a distance of B.2/2+δ·sin(−90°)=B.2/2+δ to the first end point E1. The saw arm 17 is then pivoted into the third main cutting angle of −180° (
Since the third main cut is the last main cut of the main cutting sequence, before the processing of the last main cut a corner processing of the first end point E1 is done. For that the saw head 14 is moved with the saw arm 17 inclined at −180° (
After the corner processing of the first end point E1, the third main cut is done with the saw arm 17 inclined at the negative third main cutting angle −α3 in the positive the direction 56. The feed movement of saw head 14 is stopped if the pivot axis 23 has a distance of √[h3(D3−h3)]+δ·sin(180°)=√=h3·(D3−h3)] to the second end point E2, where h3=h(−α3, D3)=D3/2−Δ−δ·cos(−180°)=D3/2−Δ+δ is the penetration depth of the saw blade into the workpiece 24 the negative third main cutting angle −α3 with the third diameter D3, which corresponds to the second saw blade diameter D.2. If at the second end point E2 an overcut is allowed, after the third main cut there is a corner processing of the second end point E2 (
In the separation cut shown in
The cutting sequence comprises a first main cut at a first main cutting angle α1 of saw arm 17, a first diameter D1 and the first penetration depth h1 of the saw blade used, as well as a subsequent second main cut at a second main cutting angle α2 of saw arm 17, a second diameter d2 and a second penetration depth h2 of the saw blade used.
The first main cut is made by the first saw blade 16.1 and the first blade guard 21.1 and the second main cut is made by the second saw blade 16.2 and second blade guard 21.2. The first diameter D1 and the first width B1 of the first main cut match the first saw blade diameter D.1 and the first blade guard width B.1. The second diameter D2 and the second width B2 the second main cut match the second blade guard diameter D.2 and the second blade guard width B.2.
The boundary conditions that apply for the park position are:
The dismounting of the first saw blade 16.1 and first blade guard 21.1 and the mounting of the second saw blade 16.2 and second blade guard 21.2 occur in the basic position of saw arm 17 at 0°. If the second end point E2 is a barrier as in the embodiment, before the start of the controlled processing a mounting distance Δmount is additionally established. The mounting distance Δmount assures there is a sufficient distance for the operator between the barrier and the saw blade and between the barrier and the blade guard to grasp the saw blade and blade guard; a suitable mounting distance is, for example, 10 cm.
With the processing with blade guard, in principle a minimum distance to the second end point (E2) of Bb.1+Δmount for the first blade guard 21.1 and Bb.2 +Δmount for the second blade guard 21.2 is necessary. Since the first blade guard width B.1 is smaller than the second blade guard width B.2, with symmetrical blade guards it is sufficient to consider the second blade guard width B.2 in the calculation of the minimum distance for the mounting; with asymmetrical blade guards, both minimum distances must be considered. The pivot axis 23 must have a distance of maximum value [Bb.1+Δmount, Bb.2+Δmount] to the barrier at E2 (
The necessary distances to the pivoting out of the first saw blade 16.1 and pivoting in of the second saw blade 16.2 at the second end point E2 depend on the first main cutting angle α1 of the first main cut and the second main cutting angle α2 of the second main cut. A distinction must be made between negative main cutting angles of −180° to 0°, positive main cutting angle α of 0° to 90° and positive main cutting angle α of 90° to 180°. For positive main cutting angles α of 90° to 180° the critical angle αcrit of ±90° must be considered, since the barrier at the second end point E2 may not be exceeded in the pivoting movement. The pivot axis 23 at the critical angle αcrit of +90° has a distance to the second end point E2 of Bb.1+δ·sin(90°)=Bb.1+δ for the first blade guard 21.1 and Bb.2+δ·sin(90°)=Bb.2+δ for the second blade guard 21.2 (
At negative first main cutting angles −α1 of −180° to 0°, the pivoting out of the first saw blade 16.1 into the basic position at 0° occurs on the side facing away from the second end point E2 and the displacement is negative. For negative second main cutting angles −α2, positive second main cutting angles α2 of 0° to 90° and positive second main cutting angles α2 of 90° to 180°, different distances result.
At negative second main cutting angles −α2, the pivoting in of the second saw blade 16.2 occurs at the side facing away from the second end point E2 and the distance necessary for the pivoting in is smaller than the minimum distance to the mounting; the control unit 29 chooses as park position for wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount]. At positive second main cutting angles α2 between 0° and 90°, for the pivoting in of the second saw blade 16.2 a distance of the pivot axis 23 to the barrier at E2 of Bb.2+δ·sin(α2) is necessary and the control unit 29 chooses as park position for the wall saw 12 the maximum value of (Bb.1+Δmount, Bb.2+Δmount, Bb.2+δ·sin(α2)] for 0°<α2≤90°. At positive second main cutting angles α2 between 90° and 180°, the distance necessary for the pivoting in of the second saw blade 16.2 of the pivot axis 23 to barrier Bb.2+δ·sin(90°)=Bb.2+δ· and the control unit 29 chooses as park position for wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.2+δ·sin(90°)] for 90°<α2≤180°.
At positive first main cutting angle α1 of 0° to 90°, the pivoting out of the first saw blade 16.1 to the basic position occurs on the side facing the second end point E2. For the pivoting out of the first saw blade 16.1 a distance of the pivot axis 23 of Bb.1+δ·sin(α1) to the barrier is necessary. For negative second main cutting angles −α2, positive second main cutting angles α2 of 0° to 90° and positive second main cutting angles α2 of 90° to 180°, different distances result.
At negative second main cutting angles α2, the pivoting in of the second saw blade 16.2 occurs at the side facing away from the barrier and the control unit 29 chooses as park position for wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(α1)]. At positive second main cutting angles α2 from 0+ to 90°, for the pivoting in of the second saw blade 16.2 a distance of the pivot axis 23 to the barrier of Bb.2+δ·sin(α2) is necessary and the control unit 29 chooses as park position for the wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(α1), Bb.2+δ·sin(α2)]. At positive second main cutting angles α2 between 90° and 180°, the distance necessary for the pivoting in of the second saw blade 16.2 of the pivot axis 23 to the barrier of Bb.2+δ·sin(90°)=Bb.2+δ· is necessary and the control unit 29 chooses as park position for wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.2+δ·sin(90°)].
At positive first main cutting angle α1 of 90° to 180°, the pivoting out of the first saw blade 16.1 to the basic position occurs on the side facing the second end point E2. For the pivoting out of the first saw blade 16.1 a distance of the pivot axis 23 of Bb.1+δ·sin(90°)=Bb.1+δ to the barrier at E2 is necessary. For negative second main cutting angles −α2, positive second main cutting angles −α2 of 0° to 90° and positive second main cutting angles α2 of 90° to 180°, different distances result.
At negative second main cutting angles α2, the pivoting in of the second saw blade 16.2 occurs at the side facing away from the barrier and the control unit 29 chooses as park position for wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°)]. At positive second main cutting angles α2 from 0° to 90°, for the pivoting in of the second saw blade 16.2 a distance of the pivot axis 23 to the barrier of Bb.2+δ·sin(α2) is necessary and the control unit 29 chooses as park position for the wall saw 12 the maximum value of [Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°), Bb.2+δ·sin(α2)]. At positive second main cutting angles α2 of 90° to 180°, the distance necessary for the pivoting in of the second saw blade 16.2 of the pivot axis 23 to the barrier of Bb.2+δ·sin(90°)=Bb.2+δ· is necessary and the control unit 29 chooses as park position for wall saw 12 the maximum value of Bb.1+Δmount, Bb.2+Δmount, Bb.1+δ·sin(90°), Bb.2 +δ·sin(90°)].
If processing of the first and/or second partial cut is done without blade guard, the second saw blade edge 62 instead of the second saw blade edge 72 is used for calculating the minimum distances for the park position and the second saw blade width B.2 will replace the saw blade diameter D.2 of the second saw blade 16.2.
In the separation cuts shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 14003099.0 | Sep 2014 | EP | regional |
This application claims the priority of International Application No. PCT/EP2015/070008, filed Sep. 2, 2015, and European Patent Document No. 14003099.0, filed Sep. 8. 20.14 the disclosures of which are expressly incorporated by reference herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2015/070008 | 9/2/2015 | WO | 00 |
