WO2011023186A2

WO2011023186A2 - Device for compensating acceleration forces by means of impulse coupling in measuring machines and tool machines in at least one translatory active machine axis

Info

Publication number: WO2011023186A2
Application number: PCT/DE2010/001038
Authority: WO
Inventors: Andreas Ehlerding
Original assignee: Andreas Ehlerding
Priority date: 2009-08-27
Filing date: 2010-08-27
Publication date: 2011-03-03
Also published as: DE102009039201B3; WO2011023186A3; WO2011023186A4

Abstract

The invention enables impulse coupling in measuring machines and tool machines to be used in a particularly efficient manner, comprising machine axes having relatively long translatory movements and which have high acceleration, a net load which is to be displaced along said type of axis and one or several compensation masses associated with said net load being guided in a sliding manner parallel to each other in the direction of said machine axis, and an inlet and outlet of a first drive system which can be accelerated relatively highly being provided on the net load and the compensation mass for the relative movement of said net load and compensation mass. According to the invention, at least one of the parts of said net load or said compensation load also comprise the inlet or the outlet of a second drive system with relatively low acceleration. The other side corresponding to said drive with relatively low acceleration is on the structure supporting the respective machine axis and is used for the common displacement with relatively low acceleration of said net load and compensation mass, along said supporting structure. The superposition of the movement parts with low and high acceleration enables high acceleration along said machine axis.

Description

Device for compensation of acceleration forces by means of

Pulse decoupling in measuring and machine tools in at least

a translationally effective machine axis.

Technical field and state of the art

The advancement of new material processing, bonding or assembly techniques such as laser cutting and welding, high speed milling, rapid prototyping or post-processing such as hardening, coating or polishing have resulted in a growing number of machine tools with high moving speeds of their tool or workpiece carrying members.

Also in measuring machines high speeds are desired.

Tools and measuring devices are referred to hereinafter as end effectors. Movement devices of a measuring or machine tool, each one

translational or rotational movement of an end effector relative to a workpiece in an axis of a reference coordinate system of the working space of the machine will be referred to hereinafter as axes.

Machine axes are those partial movement devices which permit a translatory or rotational movement of a machine element relative to a machine element higher in the hierarchy of the machine, the hierarchy starting at the machine frame as the highest stage and at the machine axes for the direct movement of an end effector as the lowest stage ends.

Axes and machine axes may be identical, but they may as well

Achsbewegungen, with respect to said reference coordinate system, from the

Movements of several machine axes be composed.

Thus the high aimed speeds even with complicated designed

Workpieces can be used are high accelerations of the moving

Elements necessary.

In many applications, it is necessary to guide an end effector, continuously and with the highest possible constant relative velocity, along an at least partially complicated shaped workpiece, which has a substantially higher mass and / or substantially larger dimensions relative to said end effector.

This requires a relatively massive and / or long-lasting leadership structure. The more massive the moving elements are, the higher are the forces which are necessary on the one hand to achieve the desired high accelerations and on the other hand cause corresponding effects on supporting or guiding structures.

This leads to undesirable, usually elastic, deformations of these structures, which in turn often leads to oscillations on the resonance frequencies of all machine elements involved.

All of these deformations and oscillations lead to a deviation between the desired and actual path during the movement of an end effector relative to the workpiece.

Various approaches are known to mitigate this problem.

Basically distinguishable are two main branches, which however in the concrete

Application can certainly be used together.

A branch deals with the most anticipated or fast-reacting correction of a predictable or detected motion deviation, ie the error compensation.

Another branch, which deals with the present patent application attempts to keep the motion deviations from the outset small, so error prevention.

In turn, error prevention knows three sub-branches of solutions. 1. stability, 2. reduction of the moving masses and 3. impulse compensation.

Error avoidance by rigidity of the structures and damping of vibrations leads to massive machines, which require high driving forces, which means high acquisition and

Installation costs, high energy consumption and in many cases also high wear means, thus leading to high acquisition and operating costs.

These costs often exceed achievable acceleration rates

Productivity advantage.

To avoid errors by reducing the moving masses, a whole series of approaches are also known.

In addition to the use of novel materials, such as carbon fiber composites, it comes also to use alternative Achskonfigurationen, such as

Parallel kinematics, and there as an example the so-called hexapods. The basic idea here is that the various degrees of freedom required are not achieved by a series of correspondingly movable "axes", which means in its consequence that with the number of axles the required stability can only be achieved by a disproportionately fast increasing machine mass, but by usually kinematics, of length-variable rods, which are mainly free to gimbal or ball joints freely movable, an end effector or a workpiece together next to each other, so parallel, and wear them by appropriately coordinated changes in length or position of the rods, with relatively large freedom Working space are movable.

The working space of a machine using parallel kinematics, however, is relatively small when compared to a conventional machine of similar dimensions, especially when compared to machines with moving gantries.

In addition, the very complex dynamic behavior of the variable rods and this in conjunction with the heavily loaded joints of a highly accelerated and at the same time very precise movement limits.

It has also come to the development of hybrid forms that combine both traditional axle assemblies and parallel kinematics, e.g. in the form that a traditional gantry machine is a parallel kinematic instead of a multi-axis

Swivel head carries. An example of this is known from US Pat. No. 7,357,049 B2.

At the same time, such combinations have a development tendency which is almost exactly opposite that of parallel kinematics, ie even the juxtaposition of even more axes, which has already become known for some time, for example from International Patent Application WO 93/01021 A1.

WO 93/01021 A1 teaches the parallel superimposed (redundant) movement of longer base axles and shorter additional axles, wherein the additional axles are much smaller due to their smaller paths and spans and thus are lighter, that is to accelerate with less force.

Depending on the consideration, this leads to higher accelerations

with equal forces, or less repercussions at equal accelerations, so that both accuracy and speed can benefit from this. Quite the same applies to EP 927596 A2, except that not some motion axes with large masses, so to speak in smaller and lighter form, duplicated, but that a redundant effective superposition of the movement of the long machine axes by combining a perpendicular to the working surface and rotating a coupled thereto linear axis is reached.

Again, relatively high-speed movements of the tool relative to the workpiece can be achieved without this large masses must be accelerated accordingly.

One of the oldest error avoidance strategies in machines of all kinds is the movement of balancing weights, referred to above as the momentum compensation. For machine tools, this process has been known in principle for a long time. This method offers, depending on the specific embodiment, in part, a very good suppression of vibrations or other disturbing movements of machine tools, but a problem is that virtually all moving masses must be present at least twice, if the trajectories of the balancing weights are not excessively long should. Although the additional mass is theoretically overcompensated by the weaker dynamic force effects from the respective axles borne, but always only in the sum of the forces in one axial direction.

The partial loads within an axis direction, ie within an axis stage, are very high at high accelerations and the overall machine structure is complicated.

A known sub-form of the use of balancing masses is that instead of separately placed and driven balancing masses the input and output side of a moving device relative to a machine (basic) frame in a common axis remain movable and movement predominantly by common

opposite effective force effect of the drive and the mass ratios of drive and driven side are determined. Therefore, no or at least much lower dynamic forces are introduced into the machine frame itself.

This variant is also referred to as jerk or impulse decoupling and is known inter alia from DE 198 10 996 A1.

The fundamental advantage of a pulse decoupling is that there is basically no difference between the driving forces of Nutz- and balancing mass, it thus comes to a complete impulse balance, without the need to synchronize separate technical processes exactly and theoretically only one drive without further Gear stages, common for both driven masses, is needed. However, this would be a rather idealized approach, on the other hand there is a compulsion to store and move the mutually movable masses interconnected so that the overall dimensions of a translationally effective motion device with momentum decoupled, with similar masses of useful and balancing mass, correspondingly easily double can.

Long range of motion can thus pulse decoupled so far only realize so that as a balancing mass, a large machine component is used, which can not be easily excited to oscillate in the respective direction of movement, for example, a traverse or bridge along which the payload is moved and from the at least one massive part moves as a balancing mass in each case in the opposite direction, in the inversely proportional ratio to the mass ratio of payload to balancing mass.

This requires either a large complex mounted mass or a correspondingly slidably mounted support structure with a relatively large mass to keep their own motion as low as possible, both provided in each case with a drive part over the entire Bewegungssielraum.

Said storage of the support structure is very complicated and tends to result in a rather unstable overall structure of a corresponding machine.

In DE 10 2004 057 062 A1 this problem has been dealt with. However, the solution specified there leads back to completely separate and practically equal dimensioned (linear) drives in the sense of a pulse compensation (non-decoupling), only with the innovation that the drive of the balancing mass is acted upon only with the highly accelerated portions of the total movement of the useful mass , making their own langwegige leadership for the movement of the balancing mass or a disproportionately larger balancing mass, unnecessary.

According to a preferred variant of the invention described therein, even the guidance of the useful mass and the secondary (passive) side of the linear drive can be shared for the balancing mass.

The latter is again at the expense of the usable guide length, but offers the advantage that the distance between the points of introduction of the high acceleration forces of the two linear drives remains relatively small due to "gentle" tracking of the balancing mass with the movement of the useful mass, which the guides themselves and the load-bearing Relieves structures and simplifies their design and execution.This method, however, does not represent impulse decoupling, in which the large forces acting between Nutz and balancing mass, not to support structures at all to light. From WO 2008/14804 A1 (from page 8 - center, claims 6 and 21) is known in machines with redundant axes, so as described above according to WO 93/01021 A1, a pulse decoupling according to DE 198 10 996 A1 within the shorter additional axes to provide against supporting base axles.

However, a pulse-decoupled machine axis according to DE 198 10 996 A1 is suitable, on the one hand for the reasons already described, and on the other hand because a redundant supporting axis in the same direction of motion considerably influences the mode of operation of a known impulse decoupling without this being taken into account in WO 2008/14804 A1 , hardly for use as additional axle.

In addition, there are the terms mass balance (see o. Pulse compensation) and

Impulsentkopplung used in description and claims differently, so that partly remains unclear what exactly is meant, especially if alternatively or additionally an application of spring or damping means is proposed with reference to the

DE 198 10 996 A1, in which this is never meant as an alternative but exclusively supplementary, in order to keep the movements of the drive side in terms of both the deflection (spring means) and as regards the energy structure (damping means) within limits.

Above all, it remains incomprehensible to what extent such an additional axis in superimposed operation, ie when the base axis is accelerated at the same time - which is just the goal - should be non-reactive with respect to the base axis.

In fact, it does not need as an option, but essential, at least one spring means to avoid that the side facing away from the tool (drive side) of the pulse-decoupled configuration, in movements of the base axis (ie in the sense of the cited DE 198 10 996 A1, the machine frame) , runs uncontrolled over their axle limits.

In addition, for impulse decoupling (or initially impulse compensation) alternatively proposed to use an additional balancing mass against the moving mass, or the supporting portal itself as a balancing mass.

The first proposal corresponds to an already known from various documents, such as EP 1 724 054 A1 pulse compensation of additional axes (there in a

special orthogonal parallel kinematic additional axis configuration)

and the second proposal is hardly suitable to achieve the desired effect, because yes, especially with respect to the portal, as a particularly vibration-prone machine element, the high acceleration forces, especially transverse to its longitudinal axis to be avoided. Thus, WO 2008/14804 A1 does not disclose any teaching that would be practicable for the operation of pulse-decoupled axes.

As a result, it can be summarized that from the prior art for the conception of axle configurations, the highly dynamic movement of an end effector in at least one translationally effective axis, with a relatively large range of motion (ie a substantial part, from about one third of the dimensions of the corresponding overall guide device in the direction of movement of a corresponding axis, takes) no practically feasible possibility is known to use the main advantages of pulse decoupling, without disproportionately massive elements of the respective machine axis itself or corresponding balancing masses to perform parallel movable movable payload.

However, this leads to complex, massive and relatively unstable structures.

The object of the invention is therefore, the advantages of the pulse decoupling for

Making machines with relatively long-travel axes of movement practically and economically advantageous.

Description of the invention

For this purpose, it is proposed according to the main claim of the present invention, a long translationally effective machine axis to be moved payload and one or more of this payload associated balancing masses in the direction of said machine axis parallel to each other slidably and payload and

Balancing mass, drive and output of a first, relatively high acceleration

Drive system for relative movement of the payload and balancing mass to each other to provide, wherein at least one of said parts of said payload or said balancing mass, which includes one side of said high-acceleration drive, at the same time also one side (input or output) of a second relatively low

contains acceleratable drive system and the other side of this relatively low-speed drive is on the respective machine axis supporting structure and thereby a drive option for common, relatively low accelerating movement of said payload and balancing mass, relative to said supporting structure, along the said machine axis.

For not so low accelerated driven parts of said payload and balancing mass, the respective appropriate relative position for said

common low accelerating movement, in the context of relative positioning of the highly acceleratable drive, for these parts to each other, causes. To said first drive system are otherwise no special requirements. Of course, high linearity and a low power-to-weight ratio are advantageous, which is why a linear direct drive will be preferred in most applications.

Said second drive system must be able to flexibly avoid the highly accelerated movements of the either driven payload or balancing mass within an application-specific range of motion in the respective direction of movement, preferably while the lower currently active acceleration of said drive system is maintained in its effect at the same time, so that a superimposed acceleration effect arises from both drive systems compared to the payload.

This can be accomplished, for example, by combining any drive method for said second drive system with a range-adapted spring means between that drive and the driven load, however, it should be appreciated that the force transmitted by the spring means depends on the deflection of the spring means , which makes the control of such a configuration more difficult.

Therefore, a drive is preferably provided for said second drive system, which can generate a constant force regardless of its direction of movement and speed, so that as easily as possible a linear force superimposition of the two drive systems can take place.

Also suitable for this purpose is a linear direct drive, in which it is relatively easy, by means of control measures (such as commutation) between a proportionality independent of speed and position

Input signal and force to produce.

Compared with the hitherto most obvious known prior art from the document DE 10 2004 057 062 A1, the following advantages result in particular:

1. There is a lifting of the high acceleration forces directly at the place of their

Originating, so in the calculation of the drive parts between payload and balancing mass, there maximum over the length of the required range of motion.

The load-bearing structures are completely free from high acceleration forces.

2. The long drive path for the relatively low accelerations can be realized much cheaper because of the much lower required forces and powers. 3. All motor control and control components for the high power range are just necessary and it can not come in case of errors in principle not asynchronous high accelerations of payload and balancing mass.

This simplifies the construction and increases the operational safety.

4. The total movement in an axis according to the invention, is divided into a high acceleration portion within a relatively small range of motion for the said first drive system and a low acceleration portion within the entire range of motion of the respective axis.

This formulation and its concrete meaning by no means coincide with the formulation which also applies to redundant translationally effective additional axes.

Thus, all knowledge that has been collected so far in this area can be transferred largely unchanged to an axle configuration according to the invention, so that there is a wide range of possibilities from the outset.

5. The more favorable movement distribution, according to the present invention, leads to a lower effective space requirement of a machine axis of the same length.

(In the prior art according to DE 10 2004 057 062 A1 must be in a

Movement of payload and balancing mass on a common leadership

a relatively large "safety distance" are maintained in order to guarantee sufficient impulse compensation in all movement situations.)

An inventively designed machine axis has the following advantages over the alternative prior art, after the impulse decoupling a much higher balancing mass over the payload is provided to restrict the movements of the balancing mass,

1. First of all, point 2 of the previous list also applies here:

The long drive path for the relatively low accelerations can be realized much cheaper because of the much lower required forces and powers.

2. The total mass of an axis according to the invention is much lower at the same length, at best by an order of magnitude.

As a result, an axle according to the invention u.a. rather, to be part of a movable machine element, for example in multi-axis configurations.

3. Due to the much lower masses movably mounted, the structure of a machine according to the invention is simplified and at the same time the stability increases. Concerning point 2, it should be noted in a restrictive sense that an axis which is pulse-decoupled according to the invention is much better suited for multiaxial configurations, for example for moving an end effector relative to a surface, than the variants known from the prior art, but nevertheless in most conceivable applications It makes more sense to conceive of a pulse-decoupled axis according to the invention as a supporting axle within a trailing axle, since there are usually more sensible alternatives for the axles lying further down in the machine hierarchy, ie those which are closer to the end effector, which makes sense in conjunction with one designed and used machine axis according to the invention form an optimal combination. This is also a reason why in this document of a moving payload and not a moving end effector is mentioned, since this is usually only indirectly moved.

Correspondingly particularly suitable machine concepts should be described as possible developments of the invention in the following with some examples.

Before that, however, a few basic variants, which are conceivable depending on the application-specific circumstances, and possible principles to be observed for the application of the invention are listed.

According to the invention, every conceivable type has long been translationally effective

Machine axis to be moved payload and one or more of this payload

associated balancing masses in the direction of said machine axis to lead parallel to each other so that payload and balancing mass, by driving and driving a highly accelerated drive system for relative movement to each other, can be connected, with its range of motion is less than the entire range of motion in said machine axis.

Usually such a drive system in the form of two in each case on payload and

Drive mass distributed sides of a common linear drive can be provided.

The type of payload and balancing mass management will depend very much on the circumstances of the application. If, for example, a movement of a machine axis according to the invention is planned transversely to its direction of movement, then the guides and their supporting structures must be suitable for absorbing, in addition to gravity, the occurring acceleration forces in an application-oriented manner, ie in particular with sufficiently low deformation.

The forces between the payload and the balancing mass should preferably act on one axis through the center of mass of both masses, which runs parallel to their direction of movement, Otherwise, by means of said guide torques from the relatively high accelerated movement of these masses are introduced into each other in the supporting structures, which can greatly limit the usefulness of such impulse decoupling.

There are three basic approaches:

1. payload and balancing mass are each moved in a rather compact form on an axis and preferably also on the same guide and preferably connected to a single drive system with effectively repellent and attractive effect acts essentially along a rod-shaped structure by the centers of gravity of the two driven masses ,

Examples could be corresponding voice coil drives, symmetrically arranged common linear drives or ball screw spindle drives.

2. payload and balancing mass are moved side by side, permeable to each other in the transverse profile, so that they can be moved past each other, yet they preferably both have a focus on a common axis of movement through which also acts the effective force of the common drive system.

A symmetrically arranged linear drive would be particularly suitable since it avoids the occurrence of disturbing torques most effectively.

If payload and balancing mass move past each other during their relative movement, it is difficult to provide common guidance for both elements, therefore in these cases it may be preferable to provide separate payload and balancing mass guides, which may also mean that the desired symmetry of the Driving forces can be achieved by a compact designed payload, which is driven by symmetrically arranged linear drives against a plurality of balancing weights, preferably two equal, as parts of said first drive system.

3. The balancing mass is guided on the payload, or vice versa, for the reasons already mentioned a symmetrical distribution of the balancing mass, possibly on two separately guided and driven balancing masses is possible.

In principle, it is possible according to the invention to make said second drive system also act between leveling compound and supporting structures, as also shown in the concluding illustrated examples. In many cases, however, a drive between payload and supporting structures may be preferable because the payload and not the balancing weights are structurally closer to the end effector and thus control and Control influences on said second drive system have a more direct influence on the controlled or controlled size.

A machine axis according to the invention should be application-specific with the same

Be operated measuring systems, such as a conventional linear axis.

Only the position of the payload relative to the load-bearing structures is relevant.

It may be expedient to provide an additional measuring system within the said first drive system, for example for Kommutierunszwecke the corresponding linear drives or for accurately tracking the relative position between payload and balancing mass.

However, in many applications, one or a small number of

Position sensors for particularly prominent operating cases, such as center position or some defined axis positions are completely sufficient to achieve a correct overall function, since the actual relative position of the balancing weights usually results from such punctual data and calculations during the movement with sufficient accuracy for operational safety.

For the precise operation of a machine axis according to the invention, these data are basically rather uninteresting, since a common control of the payload on the two drive systems mainly takes place via a force distribution.

From the cited prior art it is already quantitatively evident that machine axes according to the invention can also be used for the field of laser cutting, since most concrete examples deal with this application.

Therefore, the concrete examples of the application of the invention described here are also intended to deal with this subject, which of course does not mean that the example concepts described are not suitable for a variety of other applications, in modifications that are easy for the person skilled in the art.

One of the most widespread applications of laser cutting is the cutting of plate-shaped raw material on so-called flatbed laser machines.

The vast majority of such laser cutting machines is divided in the

Basic construction in two groups:

Common to both is that, usually on a shuttle table, while processing stationary positioned in the editing room material. The somewhat more traditional fraction uses a gantry arrangement of two drives and corresponding guides to position a portal above the material next to the work area, usually along the larger dimension of the processing area, which on most machines has a horizontal processing field of 3 x 2 meters up to 5 x 3 meters and usually only has a height of a few centimeters.

Since the free-standing guides of the movable structures on the portals must be slightly longer than the material to be processed, thus creating portals with cantilevered lengths of 2.5 to 3.5 meters, which is often a total of 3 to 4 meters long movable Represent structure.

In order to achieve good accessibility of the working space in such machines, it would be desirable to move the portals with stands, so that the guides can be arranged below the working space. However, this contradicts a high

Machine dynamics, by the additional moving masses and elasticities, so that predominantly the guides of the portals takes place directly on the working plane.

As a result, a second type of construction developed over time, moving the portal's management over and behind the processing room. From the cantilever is held by the back of the processing room ago with superimposed guides is about a relatively wide-sized central guide over the working space, up to corresponding combinations of individual guides behind and above the working space, the spectrum ranges.

Especially the first two subspecies are only partially suitable for very long transverse axes with high accelerations, as with increasing distance of the end effector from the suspension, disturbing forces and instabilities occur.

Naturally, this also applies to the other variants shown overall, but only to the same extent only at higher spans.

As described in detail in the prior art, a solution to this problem was seen in the use of redundant auxiliary axes, so that the relatively unstable long gantries and cantilevers only have to take a proportion of movement with relatively low acceleration in a total movement with high acceleration.

The fact that in this case repercussions of the additional axes to the so-called base axes occur and that also for this purpose solutions in the sense of impulse compensation have been developed, has also been described in the prior art. Really well-functioning examples of these technologies for laser cutting are so far rare and this is due in addition to some problems yet to be solved with the coordination of the redundant axes also for that in laser cutting on flatbed machines, which takes place predominantly with CO ² lasers in the infrared range, for each Additional axis either a precisely aligned and quite complex deflecting mirror is necessary or another complicated and therefore less robust optics for guiding the beam is provided on the material.

Also, the cutting head should be as universally applicable, which in turn leads to a certain minimum size and mass, which complicates a two-dimensional acceleration on stacked axes with momentum compensation.

The two-dimensional parallel kinematic solution approach from EP 1 724 054 A1 only helps with relatively light cutting heads and rather short-path additional axes, so that even relatively high accelerating base axes are necessary if work is to be carried out at higher constant speeds, which are now customary in the thin sheet sector ,

Incidentally, it can be noted that an identical range of motion in both axes, as provided in EP 1 724 054 A1, usually just does not meet the actual requirements of a two-dimensional additional axis configuration, since the need for the range of motion behaves ungekehrt proportional to the maximum usable acceleration of the respective base axes ,

Since the vast majority of base axis configurations have extremely different acceleration potentials in the horizontally acting base axes, so for example with respect to the flatbed laser cutting machines listed above, the mobile portal a much lower acceleration, provided the same precision requirements allowed as a movable structure on the portal, would also be corresponding additional axes suitable for different movement latitudes, in order to achieve comparable properties for each of the two axles in the overall result.

Thinking further in this direction, it may already be sufficient for many applications, if a redundant additional axis is provided only in the axis for moving the portal, compared to the axis longest of the portal comparable

To achieve accelerations. This provides an axis configuration that matches the one set up at the beginning

Demands for an additional axis configuration already largely corresponds to be suitable to be able to move even versatile and heavy cutting heads and to get along with the least possible deflecting mirrors for beam guidance.

While in such an axis configuration, a pulse compensation of the redundant additional axis for movement in the direction of the portal movement, relatively simple in the prior art is possible to realize the highest possible acceleration largely without feedback, this would be for the long axis along the portal, the same time also the said additional axle contributes, according to the prior art only very complicated and with high moving masses in this axis feasible, so that in turn would negatively affect the base axis to move the portal, which in turn drives the requirements for the range of motion of the additional axis , which makes it larger and heavier, which in turn leads to a more stable construction of the portal, so that a total of a much more massive construction and effort arises that would make most conceivable applications uneconomical.

The option to dispense with a pulse compensation and / or to use other compensation methods, does not exist at the high desired accelerations, in the range beyond 60m ² / sec, when at the same time high and consistently achievable precision is required.

To solve such a problem is a particularly suitable example

Application of the present invention.

An inventive pulse-decoupled axis along a portal requires little additional space and is only slightly larger mass than the standard design. At the same time, an extremely powerful drive for the highly accelerated motion components in this axis can be provided, which allows a substantial approximation of the acceleration to the level of the additional axis in the other axial direction, and although the portal guides and thus the entire machine frame compared to the variant without impulse decoupling rather is relieved, so with the same requirements a less robust design would be possible.

In order to explain the possible practical application of the invention in some detail in more detail, is for simplicity of a known type of machine as

Design basis assumed and shown as an example in a

According to the invention set up machine type could be redesigned. Flatbed laser cutting machines are known, as described for example in US 2005/0103764 A1, which move a projecting arm in an X axis over the material to be processed and an additional axis which is also movable in the X axis (X2 axis) move said arm in a Y axis.

The additional axis contains a further possibility of movement carried by it in the vertical Z axis, to which the laser cutting head is finally attached as the end effector of this example.

The ball screw or rack and pinion drives commonly used in such machines are usually not capable of applying a constant force to a driven load, regardless of the relative speed of the driven load to its

Leadership, which can also be changed by external accelerations.

As already stated above, this is in particular linearized for control purposes

(commutated) linear direct drives suitable.

In particular, for the movement of the Y-axis along said arm of the machine, therefore, a corresponding drive is preferably provided.

In the example to be adapted, the motors for the rack and pinion (there no. 58) and the racks are to be replaced by ensprechende linear actuators. This is structurally relatively easy to provide, especially since the linear drives for the said second drive system of a machine axis according to the invention must generate a lower driving force than the drives to be replaced.

The active part of the said first drive system according to the invention would then be advantageous, for example, to be mounted on top of the X2 axle device, so that a compact balancing weight above the X2 axle device by means of a passive axle

Drive parts is relatively movable in the Y direction to the X2 - axis device.

Whether said balancing mass is guided on the X2 axle device or whether a separate guide is to be provided in the cantilever arm can be used in a number of constructive ways

Depend on secondary conditions and should not be discussed here.

The load on the cantilever itself would be largely identical in both cases anyway.

Without significant loss of stability of the cantilever can be a running along the arm

Be provided bulge in which the balancing mass moves along.

Instead of two identically controlled drive trains, a single linear drive for the said second drive system of the Y axis could also be provided along the axis of symmetry of the cantilever arm, whose active part is correspondingly mounted in the middle of the X2 axis device. In this case, the space released by the replaced drives (there no. 58) can then be used for two symmetrically arranged and driven compact balancing masses with corresponding linear drives, so that the outside dimensions likewise do not change significantly.

In this variant, the guidance of the balancing masses on the X2 axle device should be advantageous over a guide on the cantilever arm, as this would then be rather expensive. When guiding and constructing the X2 axle device, however, the considerable, preferably roughly doubled, additional static load must then be taken into account.

The concrete mass of the balancing weights depends on many factors.

One of the most important parameters is the maximum acceleration through the

According to the invention second drive system can be provided. A typical one

Acceleration for a Y axis according to the example document would be 40 m / s ² .

Since, in effect, at least a two-fold dynamic relief of the basic structure should be assumed with simultaneously doubled maximum acceleration and the mass to be accelerated in the Y-axis could double at the same time, an assumption of 10 m / s ^{2 would be} a conservative approach.

At planned cutting speeds of up to 100 m / min, ie 1.67 m / s, the payload S (in this case, the X2 axis device) is based on a simplistic formula from the prior art relating to redundant additional axes (in detail in WO 2008 / 148 558 A1) S = 4 x V ² / A so 4 x (1.67 m / s) ^2/10 m / s ² = 1.12 m. As known from other documents of the prior art (for example WO 2008/151810 A1 or WO 2009/027006 A1), the demand can be reduced by mostly control measures, which effectively usually means that about 20 to 30% of the theoretical "worst case" - Values are actually needed, so that a workable value of about 25 cm can be assumed.

In order for the payload to be able to move 25 cm in a pulse-decoupled manner, the balancing weight must have the same freedom of movement for the same mass of payload and balancing weight.

Correspondingly, otherwise, according to the principle of momentum conservation, the ratio between the range of movement of the payload to the balance weight would be inversely proportional to its mass ratio. This would lead to impractically long range of motion at much lower masses of the balance weight and at much higher masses to the unfavorable load conditions, as they have already been described in detail to the prior art, so that an inventive axle concept would be pointless.

As a rule of thumb, up to a ratio between the mass of the balancing weights and the payload of about 2: 1 still a clear advantage and at ratios of 4: 1 still a slight advantage of an inventively designed machine axis over the prior art. Depending on the application, however, a much higher or lower value may apply in individual cases.

Back to the example would be so probably a balancing weight in the dimension of the payload a pretty good compromise, depending on the dimensions and guide length of

Balancing masses to a reduction in use of Kragarmlänge of only about 20 cm should lead, or just a corresponding extension must be provided.

The same applies, of course, for similar machine configurations with a double-sided driven portal instead of the cantilever.

In a configuration according to the invention, the additional axis would preferably be itself pulse-decoupled or equipped with at least partial pulse compensation.

These examples make it clear again that according to the invention, a comparatively compact and yet effective impulse decoupling becomes possible, which offers considerable advantages over the prior art and can be used much more versatile because of the resulting space and weight savings.

As already mentioned, the invention is advantageously applicable to a large number of other machine types, preferably wherever motion sequences with high constant speeds along longer, complexly shaped paths or for other reasons require long paths and frequent high accelerations at the same time.

Finally, further particularly preferred embodiments of the

Invention shown and explained with reference to drawings.

Fig. 1 shows the total view of a laser cutting machine, consisting of a

Machine bed (1) with a fixed bridge (2) along the X direction on a relatively wide central guide above the working space

Guide device (3) for moving a device according to the invention

Device (10) is provided in the Y direction. Details of the device (10) are shown in the following FIGS. 2 and 3.

The laser cutting machine includes a device cabinet (4) of the control (5) and not shown units, such as drive amplifiers, other electrical components,

Laser source and gas supplies contains.

In the working area there is a change table (6) with the material to be processed.

The drive for moving the guide device (3) in the X-direction by means of a centrally between two guides in the bridge (2) arranged linear direct drive, which allows a maximum acceleration of the device (3) of about 10m / s ² , up to the one practicable low - vibration movement of the device (3) is also possible up to the end positions of the Y axis.

The movement of the device (10) along the device (3) in the Y direction also takes place by means of linear direct drives, but in each case on both sides and close to the dashed lines (11) of the device (10) fitting, so that an impairment of freedom of movement within the device (10) is avoided. Said drive allows a maximum acceleration of 15 m / s ² , and serves the device (10) according to the invention as said relatively low accelerated

Drive system. This will be illustrated in more detail hereinafter in FIGS. 2 and 3.

2 shows a device (10) according to the invention in a first particularly preferred embodiment variant of the invention.

The device (10) can be moved by means of the guide elements (12) on the guide (11) already shown in FIG.

Said relatively low-speed drive of the device (10) by means of the active drive elements (13) on the device (10) and along the guide (11) arranged passive drive elements (14).

An additional axis unit (20), as a payload according to the invention, for highly accelerating movement of the end effector, here a laser cutting head (21), contains guides (22) and drives (23) for moving the laser cutting head (21) in the X direction, as well as guides ( 25) and drives (26) for moving the balancing weights (24), which cause a pulse compensation of the additional axis in the X direction.

The laser cutting head (21) contains a delivery option, not shown, in the Z direction.

The entire additional axis unit (20) is guided by means of the guide elements (15) on the same guide as the outer part of the device (10) and by means of

Actuators (16) according to the invention as said relatively high-speed drive system, of which only the passive side on the outer part of the device (10) is, relative to the said outer part of the said device (10) driven, which is thus used as a balancing mass according to the invention and at the same time each one side, both the relatively high-acceleration drive (16) and the relatively low-speed drive (13) contains ,

The range of motion for the highly acceleratable drive in the Y direction is about 27 cm, but is limited to about 16 cm from the fixed coordinate system of the machine by the opposite movement of payload and balancing mass, which is here assumed to be about 1.5 times the payload ,

The additional axis (20) has a range of motion of about 28 cm in the X direction, but is also effectively available without compromise, so that's the lower

Acceleration of the X-axis compared to the Y-axis in the calculation of the maximum usable cutting speed is even slightly overcompensated, and thus effectively, using the previously described design rules, a largely constant cutting speed of up to 100 m / min would be available for both axes , wherein using currently commercially available drive components, accelerations of about 70 m / s ^{2 could be} achieved in both axes.

Conventional machines similar to the type as shown in Figure 1, but without a device according to the invention (10) can be achieved according to the invention

Cutting quality into even the smallest contour details into it, usually only with maximum accelerations between 5 and 15 m / s ^{2 are} operated.

Depending on the proportions of small contour details and requirements for the constancy of the

Cutting speed, therefore, the processing times can often be lowered according to the invention by 50% to 70% and occasionally even by up to 90%.

Compared to machines which have similar accelerations in both main axes on the basis of previously known additional axes and comparable external dimensions, especially if they are indispensable for high accuracy, have prior art systems for pulse compensation or impulse decoupling, according to the invention a much larger usable range of motion of highly accelerated drive parts.

A particularly highly optimized variant of the invention in this regard

Device (10) is finally shown in FIG.

Many details correspond to the embodiment in Fig. 2, which is why, for the sake of clarity in Fig. 3 is largely dispensed with a numbering, where no changes compared to FIG. 2 result. Elements with the same function as in Fig. 2, but with a different arrangement, are given a number starting with a 3 instead of a 2. So for example, 24 turns 34, and so on.

The crucial difference between a device according to Fig. 2 and Fig. 3 can be seen therein, all the drive components for highly accelerated movement of the laser cutting head (21) and the balancing weights, so the guides (22, 25) and drives (23, 26) as Guides (32, 35) and drives (33, 36), as well as said

Balancing masses (24), here as (34), have been displaced to the outer part of the device (10), that is to say associated with the balancing mass according to the invention for impulse decoupling. The power transmission of the drives (33) for moving the

Laser cutting head (21) in the X direction takes place here by means of the additional struts (37) having a guided in the Y direction connection to the laser cutting head (21).

As a result, the laser cutting head (21) can be moved in the X direction with drives of much larger area and correspondingly higher acceleration.

Furthermore, the masses of the listed drive elements of the payload (20) are removed, which now has a much higher acceleration with the same driving force. Alternatively, the drive for the same acceleration can be made weaker. Due to the now considerably higher mass ratio between the inventive balancing weight and inventive payload, the usability of the

Range of motion for the present invention relatively high-speed drive.

The mass ratio between balancing mass and payload changes from assumed 1.5 to 1 in a device according to FIG. 2 to over 3 to 1 in a device according to FIG. 3. Thus, over 75% of the relative

Travel range effectively available, so at least 20 cm.

In operation of this embodiment of the invention, internal and external occur

Torques, which should preferably be compensated by means of separate and appropriate control of the drives (16) and (33), and correspondingly sized balancing weights (34).

Even when using such a torque compensation, the usability of the acceleration achievable by the drives (16) remains higher within the overall system for moving the payload than in the case of a device (10) according to FIG. 2. Overall, the performance of a device according to FIG. 3, with an otherwise similar expense, increased by about 1.5 times compared to a device according to FIG. 2, while at the same time distributed more harmoniously over the overall construction

Requirements for the drives, so that an even more efficient adaptation to the respective requirements of an application, in a compact and low-mass construction is possible. The acceleration in the cutting contour can be correspondingly up to 100 m / s ^{2 here} .

Of course, the movement space for the compensating masses (34) in Fig. 3 should be disguised as possible, so that ultimately again an external appearance of the device (10), as shown in Fig. 2. Because of the more effective use of the relative range of motion between the outer part of the device (10) and the auxiliary axis unit (20), the dimensions could also be nearly identical.

Depending on the type of available guide elements or application requirements, it may also be advantageous to provide no jointly used parallel management of payload and balancing mass, but a guidance of these parts with each other, so that preferably the part which also contains the inventively low-accelerating drive, in In these cases, the balancing mass is guided on the supporting structure and the respective other part, in this case the payload, is carried by the former by means of an inner guide running in parallel to the outer guide, so that the separate

Guides are each optimized for different requirements.

Again, the embodiments described in detail herein with reference to the drawings represent only a small exemplary scope of the invention.

Completely different processing methods, such as, for example, high-speed milling, grinding, polishing or assembly methods, such as rapid prototyping, can benefit greatly from the invention.

The invention can also be advantageously used in machines in which the end effector is preferably moved from point to point rather than continuously, when high speeds are to be achieved with minimal vibration excitation of the machine structures, for example by particularly precise punctiform machining or point measurements to perform high throughput.

From this it can be seen that the invention can be used advantageously for a large number of scarcely enumerable applications, in a form that is easily recognizable to the person skilled in the art.

Claims

claims:

1. Device for compensation of acceleration forces by means of

Pulse decoupling in measuring and machine tools in at least one translationally effective machine axis wherein a payload along one of such translationally effective machine axes and one or more payloads associated with these balancing masses are guided in the direction of said machine axis parallel to each other and payload and balancing mass, input and output a first, relatively high-speed drive system for relative movement of payload and balancing mass is provided to each other, whose range of motion is smaller than the entire range of motion in said machine axis characterized in that at least one of said parts of said payload or said balancing mass, which one side of said high contains acceleratable drive, at the same time also drive or output of a second relatively low acceleration

Drive system includes, wherein the other side of said relatively low-accelerator drive is on the respective machine axis supporting structure and thereby a driving possibility for common, relatively low accelerating movement of said payload and balancing mass, relative to said supporting structure, along said machine axis, wherein for itself not so low accelerated driven parts of said payload and balancing mass, each matching relative position for said common movement, in the context of relative positioning of the highly acceleratable drive, for these parts to each other, is effected.

2. Device according to claim 1, characterized in that in said second drive system adapted in the range of motion

Federmittel between this drive and the driven load is provided to the effect of the generated by said first drive system high

Acceleration force on the leadership of the said second drive system to reduce.

3. Device according to one of claims 1 or 2, characterized in that in said second drive system, a drive is provided which can generate a constant force regardless of its direction of movement and speed.

4. Device according to claim 3, characterized in that said drive is a linear direct drive.

5. Device according to claim 4, characterized in that for said direct drive by means of control measures

a proportionality independent of speed and position

can be produced between input signal and force.

6. Device according to one of claims 1 to 5, characterized in that the forces from said first drive system between payload and balancing mass act on an axis through the center of gravity of both masses, which is parallel to its direction of movement.

7. Device according to one of claims 1 to 6, characterized in that

Payload and balancing mass are moved on the same guide,

connected by one or more parts of said first drive system with repulsive and attractive effect and along a rod-shaped structure for each said part

8. Device according to one of claims 1 to 6, characterized in that

Payload and balancing mass are moved side by side

permeable to each other in the transverse profile,

so that they can be moved past each other.

9. Device according to claim 8, characterized in that common or separate guides for payload and

Balancing mass are provided.

10. Device according to one of claims 8 or 9, characterized in that a plurality of balancing weights, preferably two identical,

are provided with the said first drive system.

11. Device according to one of claims 1 to 6, characterized in that the balancing mass is guided on the payload,

12. Device according to claim 11, characterized in that a distribution of the balancing mass is provided on a plurality of separately guided and driven balancing masses.

13. Device according to one of claims 1 to 12, characterized in that within the said first drive system, an additional measuring system for continuously measuring the position is provided.

14. Device according to one of claims 1 to 12, characterized in that within said first drive system

alternatively or in addition to an existing measuring system

for continuous measurement of position,

a small number of position sensors for particularly prominent

Operating cases, such as center position or defined axial positions are provided.

15. measuring or machine tool with means for compensating acceleration forces by means of impulse decoupling in at least one translationally effective machine axis along a first such translationally effective machine axis

a) in a second axial direction and redundant to a base axis with relatively low acceleration effective additional axis with relatively high acceleration, and

b) one or more balancing masses for pulse decoupling of said

Additional axis (as a self-contained unit to be moved)

in the direction of said first machine axis

are parallel to each other and slidably guided on said additional axis and balancing weights, drives of a first, relatively high acceleration drive system for relative movement of said additional axis and balancing masses to each other, whose range of motion is smaller than the entire range of motion in said machine axis, characterized in that at least one of the parts of said auxiliary axle (as one in itself

closed unit to be moved) or said balancing weights,

which contains one side of said high-speed drive,

at the same time also drive or takeoff of a second relatively low

acceleratable drive system, wherein the other side of said relatively low accelerating

Drive is on the said first machine axis bearing structure and thus there is a drive for common, relatively low accelerating movement of said additional axis and balancing masses, relative to said supporting structure, along said first machine axis, for itself not so low accelerated driven parts of

said additional axis and balancing mass, each matching relative position for said common movement, in the context of relative positioning

the highly acceleratable drive, for these parts to each other, is effected.

16. A measuring or machine tool according to claim 15, characterized in that it comprises a device according to one of claims 2 to 14,

wherein said payload said auxiliary axle (as a in itself

completed unit to be moved) is used.

17. measuring or machine tool according to one of claims 15 or 16,

characterized in that said additional axis in their inner direction of action one at least partially

Pulse decoupling or at least partial pulse compensation

18. Measuring or machine tool according to one of claims 15 to 17,

characterized in that said additional axis is guided on a portal or cantilever

19. Measuring or machine tool according to claim 18,

characterized in that the inner direction of action of a said additional axis exclusively

parallel to the axis of movement of said portal or cantilever.

20. Machine tool according to one of claims 15 to 19,

characterized in that it is a laser cutting machine, with a laser beam

in the infrared range and corresponding deflection mirrors for beam guidance

be used.