阅读说明：本技术 用于接合或机械加工的方法及其设备 (Method for joining or machining and device therefor ) 是由 G·菲格内尔 C·扎拉尔 于 2020-01-28 设计创作，主要内容包括：本发明涉及是一种用于接合或机械加工的方法,特别是使用设备(1)的摩擦搅拌焊接方法,其中工具(6),特别是摩擦搅拌焊接工具,经由具有主轴轴线(4)的主轴(2)被驱动。为了即使当方法被应用于可达性差的位置处时,也实现高工艺可靠性,本发明提供适配器(特别是角头(3))被布置在主轴(2)和工具(6)之间,使得工具(6)绕其旋转的工具轴线(5)与主轴轴线(4)不一致,其中作用于主轴(2)上的力被测量,并且方法根据在主轴(2)处测量的力被调节。本发明还涉及一种用于接合或机械加工、特别是用于摩擦搅拌焊接的设备(1),设备(1)具有主轴箱,主轴箱具有可绕主轴轴线(4)旋转的主轴(2)和工具(6),特别是摩擦搅拌焊接工具,工具(6)能够通过主轴(2)绕工具轴线(5)被驱动。(The invention relates to a method for joining or machining, in particular a friction stir welding method using a device (1), wherein a tool (6), in particular a friction stir welding tool, is driven via a spindle (2) having a spindle axis (4). In order to achieve a high process reliability even when the method is applied at a location of poor accessibility, the invention provides that an adapter, in particular an angle head (3), is arranged between the spindle (2) and the tool (6) such that the tool axis (5) about which the tool (6) rotates does not coincide with the spindle axis (4), wherein the force acting on the spindle (2) is measured and the method is adjusted depending on the force measured at the spindle (2). The invention further relates to a device (1) for joining or machining, in particular for friction stir welding, the device (1) having a spindle head with a spindle (2) which can be rotated about a spindle axis (4) and a tool (6), in particular a friction stir welding tool, the tool (6) being drivable about a tool axis (5) by means of the spindle (2).)

1. A method for joining or machining, in particular a friction stir welding method using a device (1), wherein a tool (6), in particular a friction stir welding tool, is driven via a spindle (2) having a spindle axis (4), characterized in that an adapter, in particular an angle head (3), is arranged between the spindle (2) and the tool (6) such that a tool axis (5) about which the tool (6) rotates does not coincide with the spindle axis (4), wherein a force acting on the spindle (2) is measured and the method is controlled depending on the force measured at the spindle (2).

2. Method according to claim 1, characterized in that the control is adjusted according to the force measured at the spindle (2) and the machine constant assigned to the adapter.

3. A method according to claim 1 or 2, characterized in that forces in a plurality of spatial directions are measured at the spindle (2) and that control takes place in dependence of the distance of the tool (6) from the spindle (2) in a plurality of spatial directions.

4. A method according to any one of claims 1-3, characterized in that the measured force is multiplied by a machine constant, which depends on the distance of the tool (6) from the spindle (2), before it enters control.

5. Method according to any of claims 1 to 4, characterized in that the adapter is detachably connected to the spindle (2) and the force is measured by means of a force measuring device arranged on the adapter.

6. The method according to any one of claims 1 to 5, characterized in that the tool axis (5) is arranged at an angle (a) of 15 ° to 165 °, preferably about 90 °, to the spindle axis (4).

7. Method according to any one of claims 1 to 6, characterized in that at least two tools (6), in particular two friction stir welding tools, are arranged on the adapter and that control takes place depending on the force measured at the spindle (2) and which of the tools (6) is used.

8. A device (1) for joining or machining, in particular for friction stir welding, the device (1) comprising a headstock with a spindle (2) which can be rotated about a spindle axis (4) and a tool (6), in particular a friction stir welding tool, the tool (6) being drivable about a tool axis (5) by means of the spindle (2), characterized by an adapter, in particular an angle head (3), which is arranged between the spindle axis (4) and the tool axis (5) such that the spindle axis (4) does not coincide with the tool axis (5), wherein at least one force sensor is arranged in the region of the spindle (2) to record the force acting on the spindle (2), wherein the device (1) is implemented for controlling a force based on measurement, a method for controlling a friction stir welding, and a method for controlling a force based on measurement, Preferably a friction stir welding method, in particular for carrying out a method according to one of claims 1 to 7.

9. Device (1) according to claim 8, characterized in that a force measuring system is provided for recording forces in different spatial directions.

10. Device (1) according to claim 8 or 9, characterized in that the device (1) is implemented for controlling the method depending on the distance of the tool (6) from the spindle (2) and that the control can be adjusted for varying distances, in particular varying distances due to different adapters.

Technical Field

The invention relates to a method for joining or machining, in particular a friction stir welding method using a device, wherein a tool, in particular a friction stir welding tool, is driven via a spindle having a spindle axis.

The invention also relates to a device for joining or machining, in particular for friction stir welding, comprising a spindle head having a spindle which can be rotated about a spindle axis and a tool, in particular a friction stir welding tool, which can be driven about a tool axis by the spindle.

Background

Various methods and apparatuses of this type have become known from the prior art. In methods and devices of this type, it has proven to be disadvantageous that joining or machining, in particular friction stir welding in which particularly high forces occur, is not possible in locations of poor accessibility or is possible only in the case of low process reliability.

Disclosure of Invention

This is solved by the present invention. The object of the invention is to specify a method of the type mentioned at the outset, with which a corresponding joining or machining process can be carried out efficiently and in a reliable manner even in inaccessible locations.

Further, an apparatus with which bonding or machining is possible with high process reliability even at a position where accessibility is poor will be specified.

The first object is achieved according to the invention by a method of the type mentioned at the outset in which an adapter, in particular an angle head, is arranged between the spindle and the tool such that the tool axis about which the tool rotates does not coincide with the spindle axis, wherein the force acting on the spindle is measured and the method is controlled in dependence on the force measured at the spindle.

As part of the present invention, it was found that if the force acting on the spindle is measured and, according to the force control method measured at the spindle, using an adapter such as an angle head, for example, friction stir welding is possible even at a position where accessibility is poor. As a result, damage to both the tool and also the spindle, which can be caused by high forces occurring in the direction of the tool axis, in particular during friction stir welding, because permissible loads are exceeded, can be prevented in a simple manner.

Instead of friction stir welding, the method can of course also be used for other joining or machining processes, in particular for drilling, lathing or milling. Although an angle head is preferably used as the adapter (with which the angle head is about 90 degrees^°May be realized between the spindle axis and the tool axis), but the adapter may in principle be implemented in any desired manner in order to beneficially form a tool axis different from the spindle axis and to reach a position inaccessible with the tool.

Typically, the method is controlled such that the advancing direction, the advancing speed, the normal force exerted in the direction of the tool axis via the tool, the rotational direction and the rotational speed of the tool are preset to perform the corresponding process steps, for example to generate a weld with a friction stir welding method, whereupon the method can be performed accordingly, wherein the force acting on the spindle is measured and typically continuously compared with a maximum value, for example corresponding to an allowable mechanical load of the device (in particular the spindle or the adapter) or the tool. If it is determined that the maximum value has been exceeded, the forward speed, the normal force of the tool in the direction of the tool axis, and/or the rotational speed of the tool are changed until the measured force again falls below the maximum value, possibly until it falls below an additional lower threshold value. The forward speed, the normal force of the tool in the direction of the tool axis, and/or the rotational speed can then be changed again until these parameters reach the preset or original value again before the maximum value is exceeded.

It is advantageous if the control is adjusted according to the force measured at the spindle and the machine constants assigned to the adapter. Thus, via the force measured at the spindle, the forces and moments present at the tool can be deduced by means of the machine constants. Since substantially any desired distance and angle between the tool and the spindle is possible with an angle head, the forces occurring at the spindle and the tool may vary accordingly. The machine constants generally correspond to the geometry of the adapter in order to calculate the force acting on the tool arranged on the adapter at the force transmission point with the aid of the force measured at the spindle. Via a conversion by means of machine constants, the load on the tool spaced from the spindle can thus be inferred indirectly via the force or forces measured at the spindle. As a result, the impact of the tool can be indirectly recognized, for example, via high forces at the spindle, even if no force measuring device is usually arranged on the tool itself. The arrangement of the force measuring device on the tool itself is therefore not necessary to prevent damage to the tool during the method.

In the methods from the prior art, damage to the spindle frequently occurs on the spindle bearing, since even if forces in the direction of the spindle axis, axial spindle forces and forces on planes perpendicular to the spindle axis, shearing spindle forces are usually measured in the spindle, during the force transmission at locations spaced apart from the spindle, high bending moments act on the spindle, which subject the spindle bearing to additional loads. By taking into account the geometry of the adapter or the distance of the force transmission point from the spindle, this bending moment can also be determined mathematically with the help of the measured axial and shear spindle forces, and the method can be controlled based on the corresponding maximum bending moment at the spindle in order to prevent damage to the spindle bearing.

It is preferred that the forces in the plurality of spatial directions are measured at the spindle and that the control takes place in dependence of the distance of the tool from the spindle in the plurality of spatial directions. For example, a force at the spindle in the direction of the spindle axis or a shear force on a plane perpendicular to the spindle axis may indicate an unacceptably large bending moment at or in a tool spaced from the spindle, so that the method must be limited in order to prevent damage to the tool. Thus, by measuring the axial spindle force and the shear spindle force, the force at the tool in the direction of the tool axis (i.e., the axial tool force) and the force at the tool in the direction perpendicular to the tool axis (i.e., the radial tool force), as well as the load on the tool due to bending moments, can generally be inferred. By correspondingly including the distance of the force transmission point from the spindle, the moment at the spindle about an axis perpendicular to the spindle axis can also be determined by means of the measured force in order to prevent impermissible loads on the spindle bearing.

The conversion of the measured spindle force and possibly also the measured spindle torque into a force or torque acting on the tool is facilitated as soon as the distance between the position at which the force at the spindle is measured and the tool is known from the geometry of the angle head and the device.

A particularly simple control results if the measured force is multiplied by a machine constant that depends on the distance of the tool from the spindle before the measured force enters the control. Of course, the machine constants may also have a vector format or a matrix format, in particular if forces and possibly moments are measured in a plurality of spatial directions, and enter into the control. Furthermore, the machine constants may also be changed during the method in order to adapt the conversion from spindle force to tool force to the distance between tool and spindle, which may vary due to, for example, a forward movement.

It may also be provided that the method is implemented to be performed with different adapters, such that the machine constants are changed during a change in the adapter. For example, the machine constants can be impressed electronically in the angle head, so that the controls normally acting on the spindle drive automatically acquire the machine constants during the exchange of the adapter or angle head and are therefore adapted to the geometry of the angle head or possibly the maximum load in the event of a change of the angle head.

It has proven effective that the adapter is detachably connected to the spindle and the force is measured by means of a force measuring device arranged on the adapter. The force or forces in a plurality of spatial directions can thus be measured at the spindle with a force measuring device arranged on the spindle itself and with a force measuring device arranged at the angle head. In particular if the force measuring device is arranged directly on the angle head, it may already be configured such that the output signal of the force measuring device entering the control is already mathematically corrected for the distance of the tool from the spindle. The conversion of the measured force into a value directly suitable for control then takes place in the angle head itself.

With an adapter such as an angle head, substantially any desired angle between the spindle axis and the tool axis can be achieved. It is preferred to provide that the tool axis is arranged at 15 relative to the spindle axis^°To 165^°In particular about 90^°. For example, a friction stir welded connection can then also be produced at a location which is usually embodied very heavy and would not be accessible to a large device in order to exert a correspondingly large force, and also on a surface which is only at a small distance from the opposite component so that a correspondingly large device cannot be positioned directly above the surface on which the weld seam is to be formed.

In order to be able to carry out the corresponding process, in particular on opposing parts that are separated by a small distance, it is advantageous if at least two tools, in particular two friction stir welding tools, are arranged on the adapter and the control takes place depending on which of the forces measured at the spindle and the tools is used. The adapter is then embodied as a corner head, wherein two tools are arranged at opposite ends. Further, the tools may also have a common tool axis aligned at an angle to the spindle axis. Thus, with the friction stir welding method, a weld can be applied in a simple manner to closely spaced opposing surfaces, or correspondingly arranged components can be welded together with a reliable process. If the control also takes into account which of the two tools is currently engaged, it is ensured that the distance between the force transmission point and the spindle is correctly included and the force is accurately determined in order to control the method to achieve the allowable load.

A further object is achieved according to the invention by a device of the type mentioned at the outset in which an adapter, in particular an angle head, is arranged between the spindle axis and the tool axis such that the spindle axis does not coincide with the tool axis, wherein at least one force sensor is arranged in the region of the spindle to record the force acting on the spindle, wherein the device is implemented for controlling a measuring-based force, preferably a friction stir welding method, in particular for carrying out the method according to the invention.

It is advantageous if a force measurement system is provided to record forces in different spatial directions. Typically, shear forces are recorded on a plane perpendicular to the spindle axis, and forces in the direction of the spindle axis are recorded at the spindle and/or headstock. The force measuring system can be arranged between the spindle and the headstock, or on the angle head itself, and is usually calibrated to the force transmission point. Usually, the direction of rotation of the tool is also included in the control, since said direction of rotation is related with respect to the moment acting on the tool or the spindle.

It is preferably provided that the device is implemented for controlling the method in dependence on the distance of the tool from the spindle, and that the control can be adjusted for varying distances, in particular due to different adapters.

Drawings

Additional features, benefits and effects of the present invention are derived from the exemplary embodiments described below. The drawings to which reference is hereby made show the following:

FIG. 1: apparatus for carrying out the method according to the invention.

Detailed Description

Fig. 1 shows schematically in a perspective view an apparatus 1 according to the invention for carrying out the method according to the invention, wherein the apparatus 1 illustrated in the exemplary embodiment is implemented for carrying out a friction stir welding method.

It is visible that the spindle 2, which is connected to a not shown motor, via the spindle 2, the driving takes place, wherein the spindle 2 is connected to a tool 6 via an adapter embodied as a horn head 3, the tool 6 being connected to the horn head 3 such that the tool 6 can be rotated about a tool axis 5. The tool axis 5 is thus at about 90^°Is aligned with the spindle axis 4 and the tool 6 is embodied as a friction stir welding tool. The pressing of the tool 6 in the direction of the tool axis 5 can thus take place by a movement of the spindle 2 in the direction of the tool axis 5. The advance of the tool 6 in a plane perpendicular to the tool axis 5 can also be achieved by a corresponding movement of the spindle 2.

In the friction stir welding method, a high force acts on the tool 6, in particular an axial tool force 7 as a result of the friction stir welding tool pressing against a workpiece, not shown, on which a weld seam is to be formed in the direction of the tool axis 5. Furthermore, during the movement in the advance direction 12, radial tool forces 8 caused by the advance, as well as moments due to the rotation of the tool 6 about the tool axis 5, which additionally subject the tool 6 to torsional stress, act on the tool 6. The force is transmitted to the tool 6 at a force transmission point on the tool tip where the weld is formed.

At the spindle 2, i.e. at a location spaced from the tool 6, a force measuring device (e.g. a force measuring sensor 9) is arranged, which is illustrated as an example in fig. 1 and with which an axial spindle force 10 and a shear spindle force 11 can be measured. The force measuring device can be positioned, for example, between the spindle 2 and the headstock, or at the angle head 3, or on the adapter itself in the region of the spindle 2. In order to prevent damage to the tool 6, the load acting on the tool 6 is indirectly inferred via a force measuring device arranged at the spindle 2. For this purpose, the force measured on the force measuring device at the spindle 2 is converted into a force acting on the tool 6, wherein the conversion thus takes place as a function of the distance of the tool 6 or the force transmission point from the spindle 2, in particular the spindle nose (for which the forces and moments at the spindle 2 are generally known), or on the basis of the distance of the force measuring device from the tool 6 in both directions, possibly also in other spatial directions, of the direction of the spindle axis 4 and of the tool axis 5. The forces and moments occurring in all spatial directions are usually measured so that the forces acting on the tool 6 can be accurately inferred. As a result, in particular a collision of the tool 6 can be reliably detected, and the method can be adjusted in a timely manner before the tool 6 or the device 1 is damaged. In addition, by including the distance of the force transmission point from the spindle nose in the control, for example via the machine constants by which the axial spindle force 10 and the shear spindle force 11 are multiplied, it is then also possible to infer the bending moment acting on the spindle 2 in order to determine the load on the spindle bearing if said bending moment cannot be directly registered. The method may be adjusted as such if it is determined that the allowable load of the spindle bearing has been exceeded before the spindle bearing is damaged.

In the method, the measured force is continuously compared with a limit value corresponding to the maximum allowable load of the device 1 and the tool 6. When the measured value exceeding the limit is registered by the force measuring device, control takes place in that the pressing force in the direction of the tool axis 5, the advancing speed on a plane perpendicular to the tool axis 5, and/or the rotational speed of the tool 6 about the tool axis 5 is reduced until the load at the spindle 2 and at the tool 6 within the permissible limit can be inferred based on the force measured on the force measuring device.

With the method according to the invention and the corresponding device 1, in particular the friction stir welding method, can be performed in an efficient manner even at locations with poor accessibility, wherein damage to the friction stir welding tool and the device 1 can be reliably prevented. On the one hand, a collision of the tool 6 with the component can be reliably detected. On the other hand, damage at the spindle 2 is prevented, in particular damage in the spindle bearing due to bending moments caused by the long rod arm of the angle head 3.

In addition to friction stir welding, the method according to the invention and the corresponding device 1 can also be used for milling, lathing and/or drilling, wherein the corresponding advantages are equally obtained.