CZ2002139A3 - Manufacturing machine, in particular machine tool - Google Patents

Abstract

In the present invention, there is disclosed a manufacturing machine comprising a stationary base part (2) and at least one mechanical group (20) with supporting systems for at least one workpiece (5) and at least one another mechanical group (21) with supporting systems for at least at least one tool (6). One mechanical group (20) of total weight (MW) consisting of a workpiece system (52) carrier (51) with weight (ma) and the workpiece system (52) with a weight (mb) carried thereon and intended for at least one workpiece (5) and the other mechanical group (21) of total weight (MT) consisting of a workpiece system (54) carrier (53) with weight (mc) and the workpiece system (54) with a weight (md) carried thereon (mb) and intended for at least one tool (6) are slidably mounted relative to said stationary base part (2) in at least the first coordinated direction and are coupled to each another by means of at least one feed drive actuator (22) for controlling their mutual position in at least the first coordinate direction independently on position assumed by a common center of gravity of their weights (MW) and (MT) relative to said stationary base part (2).

Description

Production machines, especially machine tools

Technical field

The invention relates to a novel design of manufacturing, in particular machine tools, in which high speeds and tool acceleration relative to the workpiece are required. A typical application field of the invention is high speed numerically controlled machine tools in which the achievement of the highest feed rates and the acceleration of relative tool movements relative to the workpiece is a fundamental parameter.

BACKGROUND OF THE INVENTION

To achieve high speeds and accelerations, machine moving masses are minimized and new types of feed drives are developed, such as rotary servomotors with single- and multi-stroke feed screws with high thread pitch, drives with stationary screws and rotating nuts, drives with racks and double pinion clearances and direct linear motors operating without mechanical coupling of solid and movable materials.

Commonly used solutions derive shifting movements, speeds and accelerations of the most massive bodies of production machines by deriving shear forces between the stationary part of the machine and the movable tool or workpiece support systems. The feed drive, for example a linear motor with direct power transmission, or a rotary servomotor with a ball screw or pinion engaging in the rack, is supported either directly or via the built-in slide guides on the stationary machine bed and vibrates the foundations.

The following problems occur with the large accelerations of the masses required today. The required frame stiffness between the tool and the blank does not allow the weight of the displaced bodies to be reduced to values that would allow the desired accelerations to be achieved. This problem is particularly severe with the most massive bodies that move directly on the ground or in the stationary bed of the machine and carry the other moving parts of the production machines carrying the tool and the blank.

• ·

-2The feed forces of a linear motor, or the feed forces of rotary servomotor mechanisms and helical or rack gears are limited for practical reasons and limit the acceleration and braking of the shifting movements of tool or semi-workpiece bodies. This problem is most serious with direct linear drives that cannot in principle take advantage of the transmission and must derive the feed force at full setpoint to overcome the frictional forces in the guide, tool and workpiece forces and infer the acceleration of the feed masses.

When using feed bolts or other mechanical gears in the feed drive, the rotating masses of the gears are added to the feed mass of the machine and increase the torque requirements of the rotary servomotor. In addition, with longer strokes there is a danger of resonance of the feed screw at critical speeds. These problems are most severe on machines with long strokes and large feed forces that require the use of feed screws of larger diameters and less lead. Replacement of feed screws with linear motors is impossible in these cases.

The sudden changes in the feed forces during acceleration and braking of the moving masses between the foundation and the accelerated masses cause impacts to the foundations of the machines, vibrate the machine frame and the frames of the surrounding equipment, reduce their working accuracy and deteriorate the environment. This problem is most severe in machines with a high mass of feed bodies, a large height to base ratio and a large required acceleration.

Impacts to the foundation can be reduced by the addition of moving masses whose movement is counter-directional to the motion of the accelerated body and kinematically coupled thereto. Examples are the propulsion of masses by a common screw with left and right threads, mass connection by rope via pulley, mass propulsion by two servomotors with opposite direction of rotation, counter-directional movement of tool and workpiece generated by crank mechanisms of forging presses and the like. During roughing, however, a large amount of chips arises, the workpiece weight gradually changes and therefore the rigid kinematic constraint is not satisfactory. This problem is most severe in high-speed machining of bulky solid parts, such as occurs in aerospace manufacturing and bulky die and mold making.

For very large and expensive products, the operator is required to travel on a platform or in the cab along with the machine part being moved to closely monitor the workflow. However, this is only acceptable up to certain limit values of acceleration of the shifted masses. This problem is most severe with larger production machines with long strokes.

Some partial solutions of the above problems of production machines are known. For example, the weight of the movable bodies can be reduced by using lightweight materials in the manufacture of the moving bodies or by using thin-walled welded bodies filled with damping materials. Increasing the stiffness of the movable bodies without increasing their weight can be achieved by using solid support frames with an increased number of guide surfaces. Impacts to the foundations can be reduced by placing machines on flexible and damping pads acting in both vertical and horizontal directions, or by damping and damping the secondary, passive parts of linear motors. The acceleration of the displaced masses can be increased by using parallel-connected linear motors. The moments of inertia and the critical speed of long feed bolts of larger diameters can be eliminated by arrangement with a rotating nut or with a rack and two mechanically pretensioned pinions. The operator's uncomfortable environment on the mobile platform can be improved by suspension or independent control of platform movement.

These known solutions concern only partial problems without constituting a principled and complex solution for the construction of high-speed production machines, in particular of medium and larger size.

Object of the invention

High-speed, high-speed machine tools of smaller sizes at the time of application exhibit rapid traverse speeds of up to 120 m / min and accelerations in multiples of Earth's gravity G. The invention allows similar parameters to be achieved for much larger machines with up to twice the body weight. In other cases, with the same weight and the same acceleration in the critical coordinate axis, the accelerating force of the respective feed drive can be reduced by half. A significant benefit of the invention is in principle the elimination of impacts to the foundation and the surrounding floor from acceleration of movements and cutting forces.

The object of the invention of the so-called seismic balanced production machines is in principle the elimination of impacts to the ground at any high velocity values and acceleration of relative

-4 tool movements relative to the workpiece, especially in the coordinate axis with the largest controlled masses moved directly on the basic, stationary part of the machine. The invention consists in utilizing the accelerating force reaction such that while the accelerating force accelerates the moving mass carrying the tool in one direction, its reaction accelerates the moving mass carrying the workpiece or workpiece in the opposite direction. The optimum case is when the two accelerated or braked masses are equal, each of which generates the same mass acceleration of the mass it controls in the opposite sense and the relative relative acceleration of the tool relative to the workpiece and the relative velocity and path increase by up to two times the conventional case. of controlled materials is connected to a stationary base.

The principal elimination of ground impacts at any high velocity values and the acceleration of the relative movements of the tool relative to the workpiece is achieved by the original machine arrangement, in which two sliding machine groups are arranged in particular in the basic coordinate axis: one carrying the tool and the other. The feed drive is built-in between these two machine groups, whose masses attract or delay each other and thus perform programmed relative tool movements relative to the workpiece, which are only decisive for achieving the workpiece shapes and dimensions. The programmed relative movements of the tool relative to the workpiece in one or more such seismic coordinate axes are realized independently of the positions and speeds of the tool or workpiece relative to the stationary machine base member. The incorporation of a drive between two moving masses in a seismic balanced coordinate axis allows the accelerating force reaction to be utilized so that while the accelerating force accelerates the moving mass carrying the tool in one direction, its reaction accelerates the moving mass carrying the workpiece or workpiece in the opposite direction.

Using this principle, virtually no accelerating or cutting forces are transferred to the foundation, since in each seismic balanced coordinate direction the internal forces of the dual mass system are connected to the foundation only by means of a slide guide. This is true even if the moving masses are different, with the acceleration, velocities and paths performed by the tool-carrying machine and the workpiece-carrying machine groups also being different, in an indirect ratio of the controlled masses on which the same large, counter-directional accelerating forces. The dual mass system oscillates in all cases around the common center of gravity of both masses, whose position in the direction of the seismic balanced coordinate axis is substantially constant and

-5 it can only shift slightly by the frictional force difference in the guide. This slight displacement of the common center of gravity does not affect the shape and dimensions of the workpiece. It is monitored on the basis of sensed and evaluated feedback information on the position and acceleration of both counter-oscillating bodies and corrected by means of a correction device.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in more detail by way of example with reference to the accompanying drawings. Figures 1 to 4 illustrate the functional principles of seismic balanced machines, with Fig. 1 schematically showing an example of a three-axis conventional production machine, Fig. 2 schematically showing an example of an analogous three-axis production machine according to the invention; a calculation diagram of the manufacturing machine, and FIG. 4 shows a diagram of the control of the correction member while the machine is running.

Figures 5 to 8 show examples of seismic machines balanced in one coordinate direction. Fig. 5 is a schematic front elevational view of a five-axis milling machine with a rotary table and a tilting spindle; Fig. 6 shows schematically a five-axis horizontal milling machine with a rotating and tilting table; stand with a rotating and tilting spindle, and Fig. 8 shows a three-axis milling machine with a vertical spindle.

Giant. Figures 9 to 12 show examples of seismic balancing of machines in two coordinate directions and variants of sliding guides. FIG. 9 shows schematically a five-axis gantry cross-cut milling machine whose tool system carrier is guided on a workpiece system carrier. FIG. 10 shows a five-axis gantry milling machine with a cross plate whose tool system carrier is guided on a cross plate. Giant. 11 shows the acceleration forces and acceleration directions of the masses of the generalized machine, and FIG. 12 shows the arrangement of the correction devices.

Giant. Figures 13 to 19 show variants of sliding guides in seismic balanced machines, with Figures 13 to 15 showing variants of sliding guides in seismic balanced machines only in the first

Fig. 16 - 19 shows the variants of sliding guides in seismic machines balanced in two coordinate directions.

DETAILED DESCRIPTION OF THE INVENTION

The originality of the embodiment of the device according to the invention results from a comparison of the embodiment of one basic coordinate axis of the conventional manufacturing machine of FIG. 1 with the embodiment of the seismic balanced basic coordinate axis of the analogous machine of FIG. 2.

The following terms are used in Fig. 1: concrete base 1, stationary base 2 of machine frame, surrounding floor 3, table 4 with horizontal clamping surface for workpiece 5, workpiece 5, tool 6, tool spindle 7, vertically movable tool carrier 8 , guide 9 vertically sliding carrier 8, horizontally sliding carrier JO of the tool system, guide 11 horizontally sliding carrier 1Ό, horizontally sliding stand 12 of the tool system, guide 13 of the machine-tool group, feed screw 14 of the basic coordinate axis, feed nut 15. basic sliding axes and a basic coordinate axis drive motor 16. The total mass in the machine-bearing assembly is MT (Mass of the Tool-Part) and the total mass in the machine-bearing assembly is MW (Mass of the Workpiece-Part).

Bodies with 1, 2, 3, 4, 5, 14, 15 and 16 do not shift in the basic coordinate axis and their total mass M3 approaches infinity. Together they form a machine group carrying the workpiece. The bodies with the reference numbers 6, 7, 8, 10, 12, 14, 15 and 16 move in the basic coordinate axis to form a machine group carrying the tool whose total mass MT is finite. The guides 13, 11 and 9 indicate the guide of the sliding bodies in three mutually perpendicular coordinate axes of the machine. The bodies 14, 15 and 16 form a displacement drive group which is rigidly connected by the body 16 to the stationary group carrying the workpiece and the body 15 to the movable group carrying the tool. The feed drive exerts an accelerating force AF (Accelerating Force) on a movable group carrying a final mass tool and an equally large reactive force (RF) on a machine group carrying an infinite weight workpiece.

The relative acceleration "ar" of the tool relative to the workpiece is equal to:

ar = AF / MT

The reaction force RF cannot accelerate the ground-bonded workpiece 5 in the basic coordinate axis of the illustrated three-axis machine, but its sudden changes still transmit vibrations and shocks to the foundations, reduce the accuracy of machine and neighboring machine operations and make the work environment unpleasant.

In FIG. 1, in addition to the traversing movement in the basic coordinate axis, further coordinate movements of the tool 6 relative to the workpiece in directions perpendicular to the direction of the basic coordinate axis are shown. In particular, the horizontal movement of the carrier 10 on the stand 12 and the vertical movement of the groups 6, 7 and 8 on the carrier 10. These movements have only a minor influence on the machine behavior and on the machine behavior due to the lower weight of the respective movable bodies. inducing shocks to the foundations.

Fig. 2 shows an example of an analogous three-axis production machine with a seismic balance of the basic coordinate axis of the invention. The machine parts remain mostly unchanged compared to the machine according to FIG. In addition, the horizontal guidance 17 of the machine group carrying the workpiece, the sliding part 18 of the correction device and the fixed part 19 of the correction device are indicated. The accelerating force of the machine-carrying machine tool is called AF (Acceleratin Force), and the counter-directional, equally large reaction accelerating force of the machine-carrying machine tool is called RF (Reactive Force).

The main principle change from the conventional machine in Figure 1 is the addition of a guide 17 and thus a release of the workbench 4 with the workpiece 5 for sliding in the basic coordinate axis of the machine. The weight of the bodies 4 and 5 of the workpiece-carrying group 5 has thus been reduced to a final MW value of the order of magnitude comparable to the mass MT of the tool-carrying group 6. The feed drive is now connected by its motor 16 to the movable workpiece carrying group. generates two counter-directional accelerating forces AF and RF of the same size. The reaction to the base of the machine has disappeared as it has been transformed into the accelerating force of the loose machine group carrying the workpiece. Although in this machine arrangement the sliding masses in the base axis are increased compared to a conventional machine, the relative acceleration of the "ar" of the tool relative to the workpiece can reach 1 to twice the original value and impact to the foundations since the mass acceleration in the base coordinate axis. are in principle eliminated.

Tttt tttttttttttttttttttttt tttttt tttttt ··· ·· tttttt tttt tttttttt

As in FIG. 1, further possible coordinate movements of the tool relative to the workpiece in further coordinate axes are shown. This is particularly the horizontal movement of the carrier 10 and the vertical movement of the groups 6, 7 and 8 on the carrier 10. In other cases, there may be further, displaceable or rotary movements in the machine and tool and workpiece bearing groups. weight of the respective bodies more significant cause of impacts to the foundations. Seismic balancing of movements in these other coordinate axes by application of the principle according to the invention is also possible, but it is unlikely to achieve an optimum ratio of counter-moving masses. An example of a seismic machine balanced in two mutually perpendicular coordinate directions will be given below in describing the solution with reference to Figs. 8, 9 and 10.

The variation of the external, especially frictional forces in the guides 13 and 17 may cause a slow displacement of the common center of gravity of the dual-mass MW and MT systems of the machine-tool and tool groups during machine operation. This is corrected by a correction device whose sliding portion 18 is connected to one of the sliding machine groups carrying the workpiece or tool and the fixed part 9 to the stationary base part 2. In Fig. 2, the sliding portion 18 is connected to the machine carrying the tool and the fixed part. 19 with stationary machine bed. In particular, a suitable non-self-locking displacement drive, such as a linear linear motor, a hydraulic or pneumatic cylinder or a non-self-locking rack and pinion type drive, may be used as an actuator of the correction device. The linear motor shown in Fig. 2 is a very suitable type of non-self-locking motor for correction devices, as it can exert a force on one of the basic machine groups at rest and at any rapid movement without interfering with the main feed drive which ensures mutual position. of both machine groups. In other cases, a brake with a controlled braking effect is also suitable. The correction of the position of the common center of gravity of the masses MW and MT can then be carried out by braking one of the machine groups during the movements generated by the relative displacement of the masses MW and MT.

The information for controlling the operation of the correction member is derived, for example, from the evaluation of the position and acceleration of the two machine groups in the basic coordinate axis and from the calculation of the resulting deviation of the common center of gravity position in the basic coordinate axis. The detected deviation of the position of the common center of gravity of the masses MW and MT is a signal for the periodic or continuous operation of the correction device, which is aimed at keeping this common center of gravity in the desired position even while the machine is running.

Fig. 3 is a calculation diagram of a manufacturing machine according to the invention that allows calculation of the relative acceleration between machine groups carrying a tool and a workpiece.

In Fig. 3, the MW machine group 20, the MT machine group, the relative displacement actuator 22 generating opposite and equally high displacement and acceleration forces AF and RF between the machine group 21 and the machine group 20 and the actuator 22 are newly identified. 23, correcting the position of the common center of gravity. In addition, in FIG. 3, the speed vw and acceleration aw of the machine group 20, the speed tt and acceleration at machine group 21 are indicated, the relative speed vr and the relative acceleration ar between the machine groups 20 and 21.

The acceleration of the workpiece-carrying assembly 20 is now: aw = RF / MW and the acceleration of the tool-carrying assembly 21 is: at = AF / MT. Since the forces of RF and AF are always opposite and equal in magnitude to the principle of the invention, RF = AF holds, and for relative acceleration of the "ar" of the tool 6 relative to the workpiece 5 follows:

ar = AF / MW + AF / MT = AF (MW + MT) / (MW MT) ie.

ar = AF (MW + MT) / (MW.MT)

For MT / MW = 1: ar = 2 AF / MW = 2 AF / MT

For MT / MW = 2: ar = 1.5 AF / MW = 3 AF / MT

For MT / MW = 0.5: ar = 3 AF / MW = 1.5 AF / MT

For a conventional machine M3 = infinity: ar = AF / MT

These relationships show that between 0.5 and 2 MW / MT, with the same accelerating force AF, there is an increase in the relative acceleration "ar" of more than 50%. Ideally, with both masses equal, the acceleration is twice that of a conventional machine in which we would accelerate one mass of both masses against a solid foundation with the same force FA. These equations provide sufficient viable and advantageous possibilities in the construction of, in particular, high speed numerically controlled machine tools and other manufacturing machines, some of which are further exemplified as examples of the application of the invention. Use of the solution according to the invention is particularly advantageous where the achievable feed force of the feed drive in the basic coordinate axis practically does not decrease with increasing relative feed rate "vr" between the tool and the workpiece. This is the case, among other things, for modern linear motors, which, for construction reasons, are large

- 10th generation of heat limited feed force, but it is available in the whole required range of feed speeds.

It follows from the principle of the invention that the workpiece-carrying machine groups 20 and the tool-carrying machine groups 21 are interchangeable without compromising the validity of the invention. It is also irrelevant whether the sliding guide of the two machine groups 20, 21 is arranged on common or separate guide surfaces on the stationary part of the machine, or whether one of the machine groups 20, 21 is guided on the stationary part and yet has a guide for the other group. . Guides of various embodiments may be used, such as the illustrated rolling guides, or sliding, hydrostatic or pneumostatic guides. The displacement drive exerting the shifting acceleration forces RF and AF between the two machine groups carrying the workpiece and the tool can also be designed in different ways without affecting the validity of the invention. For example, instead of the illustrated example with a rotating ball screw drive, a fixed screw rotating nut, rack and pinion, double rack and pinion rack, motors, hydraulic cylinder or linear motor may be used. This last option seems to be most advantageous. The relative displacement actuator 22 may also be doubled, including the associated feedback metering device, which is particularly useful for suppressing cross-links in gantry and other machines with long distances between guide surfaces. The displaceable movements of the two machine groups 20, 21 may be measured relative to the stationary part of the machine and their distance, i.e., the relative position may be measured by repeated calculations, or alternatively the distance between the two machine groups 20, 21 and the position of one of them relative to the stationary base may be measured. However, information on the relative position of the two machine groups 20 and 21 must always be evaluated and used as feedback for controlling the actuator 22 of the seismic drive of the seismic balanced axis.

Fig. 4 is a block diagram of one of the possible evaluations and continuous correction of the common center of gravity position of the two movable machine groups 20, 21 while the machine is running. In Fig. 4, the calculation element 24 is newly labeled with the generation of the signal Dx for controlling the operation of the actuator 23. Furthermore, in Fig. 4 it newly indicates: (MW - dMW) - mass of the machine group 20 carrying the workpiece 5 CF - correction force between stationary base 2 and one of the machine groups 20, 21, DP (Demanded Position) - required position of common mass center of mass (MW dMW) and MT, AP (Actual position) - actual position of mass center of mass (MW-dMW ) and MT, xO - coordinates of the required position DP of the common center of gravity, dx - deviation of the required a

- 11 actual position of common center of gravity, xw - distance of the mass center of mass (MW - dMW) from the desired position DP, xt - distance of the mass center of mass MT from the desired position DP, vw And - mass mass acceleration MT, Dx - signal of deviation of the position of the common center of gravity, derived from position data and mass acceleration (MW - dMW) and MT.

To illustrate one of the possible solutions for correcting the position of the common center of mass of MW and MT, for simplicity, the coordinate xO of the desired position of the common center of gravity was zero. Since both velocities and paths are proportional to accelerations, it was chosen for the initial state of the dual-mass system at 0: MW, aw = Mt, at, and also MW, xwO = MT, xtO. Ideally, even after a period of movement of the dual-mass system around the common center of mass, MW will apply. xw = MT. xt, i.e. xw / xt = MT / MW.

However, if the workpiece mass change or machining results in a decrease or increase in the mass of MW by dMW, the position of the common center of gravity shall be changed by dx and the following shall apply:

(MW-dMW) (xw-dx) = MT (xt + dx)

The ratio (MW - dMW) / MT can be expressed in this equation at the same acceleration force as the ratio of actual accelerations at / aw:

(MW - dMW) / MT = at / aw and then: xw. at / aw- xw = dx. (at / aw + 1)

The deviation dx of the actual position of the common center of gravity from the desired position can now be determined: dx = (xw. At / aw-xt) / (1+ at / aw)

The values xw and xt are known at all times from the data derived from the respective encoders which are part of the position servo loops of the coordinate axes. Since the actual position AP of the common center of gravity changes only very slowly, it is sufficient to evaluate deviations of this position only occasionally. For example, to measure the actual accelerations aw and at of both machine groups 20 and 21, it is possible to use continuous measurements with two accelerometers at the time of start-up and braking of rapid traverse, where the acceleration of masses MW and MT takes large values. The cutting force, like the feed acceleration force, is the internal force of the dual-mass MW, MT system, and can therefore be considered as an additional acceleration force for the determination of the acceleration ratio, which ratio · ♦ «·

- 12the acceleration will not be affected. Programmatically it is also possible to evaluate velocities vw and vt i acceleration aw and at from a sequence of continuously measured values xw and xt.

Accidental displacements of the center of gravity of the dual mass system by the friction force difference will also be compensated by repeated or continuous corrections of the position of the common center of gravity. Changes in the center of gravity of the MW itself due to changes in weight or position of the workpiece can be neglected for correction purposes. It is thus possible to control the actuator of the correction device by the deviation signal Dx by the above procedure and to maintain the common center of gravity of the dual mass system continuously at relatively constant, preselected and desired location by the correction device. It is also possible to put the center of gravity of the dual-mass system at this point even when the machine is started or after the workpiece has been changed, as the deviation value dx can be determined at the moment of rapid traverse and the correction starts.

If the ratio of masses MW and MT is fixed or known on a particular machine and the changes of their common center of gravity from the variable workpiece weight are negligible, evaluation of the acceleration ratio is not necessary since at least one of the currently required positions xw and xt can be calculated at any time. determine the deviation dx for controlling the correction device actuator 23.

The following are examples of several machines according to the invention. The machines in Figures 5 to 8 show the seismic balance in one basic coordinate axis, Figures 9 to 11 show the seismic balance in two perpendicular horizontal coordinate directions.

Giant. 5 shows a five-axis milling machine with a rotary table and a tilting spindle according to an embodiment of the invention. The machine is shown in the direction of the x-axis that is perpendicular to the display plane. In FIG. 5, the rotary table 25, the rotary table support 26, the rotary table carrier 27, the tilting spindle head 28 are newly marked: machine group feed metering device 20, machine group feed metering device 30, rotary drive 31 of machine group relative feed 20 and 21, a limited clearance pinion 32, a gear rack 33 of the relative displacement of the machine groups 20 and 21, and a linear motor 34 as an actuator of the correction device for correcting the position of the common center of gravity of MW and MIT.

Φ φ φ φ φ φ φ • φ • • • • • • • • · · · · · φ φ φ φ φ φ

The machine of Fig. 5 is an example of a five-axis milling machine whose workpiece 5 is clamped on a turntable 25 with a bearing 26 supported by a turntable support 27. The workpiece 5 is machined by a rotating tool 6 clamped in the spindle 7 carried in the tilting spindle head 28. Two angular movements of the tool spindle relative to the workpiece required for five-axis machining are performed here by the tilting spindle head 28 and the rotary table 25. a tool system carrier W and a vertically displaceable tool system carrier 8 on a horizontally displaceable tool rack 12. The bodies 5, 25 and 27 form a machine group 20 with a total weight of MW. The bodies 12, 8, 10, 28. 7 and 6 form a machine group 21 with a total weight MT. The machine has the possibility of two additional sliding movements and one tilt movement in the tool-carrying group and one rotary movement in the machine group 20, which are not seismic balanced. The drive of the relative displacement of both groups is solved by means of a rotary drive 31 with a pinion 32 and a rack 33. The drive is controlled by a relative position signal, which in this case is obtained by comparing and evaluating data of the metering devices 29 and 30. is controlled by evaluating the position and acceleration of the two masses in the manner described above and in the machine of FIG.

Fig. 6 shows a five-axis milling machine with a horizontal spindle and a rotary and tilting table. Here, the two angular movements required for five-axis machining are performed by a workpiece clamped on a rotary table supported by a tilting table. In FIG. 6, the tilting table is newly marked

35. Swivel bearing 36 of the tilting table, tilting table carrier 37, metering device 38 of relative motion of MW and MT, linear motor 39 of relative displacement of MW and MT and metering device 40 of machine group 2L

The 5-axis milling machine in Fig. 6 uses a linear motor 39 to control the relative mass feed MW and MT compared to the rotary drive 31, the pinion 32 and the rack 33 of the preceding machine. The linear motor 34 as an actuator of the correction device is again controlled by the position and acceleration data of the two masses in the manner described above, but here, unlike the previous machine, it acts on the movement of the machine group 2L.

Fig. 7 shows a five-axis milling machine with a movable stand, suitable for milling flat, large parts by high-speed machining from one side. Fig. 7 shows:

14 newly marked: table 40 with vertical clamping surface, upper support guide 41 of the mobile stand 37. multiple lateral guide 42 of table 40 with vertical clamping surface and tilting and rotating spindle head 43.

The machine of Fig. 7 is an example of a five-axis machine in which the two angular movements required for five-axis machining are performed by a spindle 7 embedded in a tilting and rotating spindle head 43. The head is supported by the horizontally displaceable tool carrier 10 and vertically displaceable tool carrier 8 horizontally. The stand 12 has a double guide: in addition to the support guide 13, it is guided by an upper support guide 41 which significantly increases the rigidity of the tool relative to the workpiece in the upper positions of the spindle head. The workpiece 5 is clamped on a table 40 with a vertical clamping surface. The table 40 also has a double guide: in addition to the supporting guide 17, it is guided by a multiple lateral guide 42 which increases the rigidity of the table by multiple guide contact with a very rigid stationary part 2. Linear displacement motors 39 are also doubled and positively coupled to the double encoder 38 In the function of the drive actuator 22, they generate two accelerating forces, the resultant of which lies close to the mass center of mass MT of the tool-carrying machine 21, eliminating the rung of the stand 12 on considerably distant guides 13 and 41. The tilting and rotating spindle head 43 allows five-axis milling the spatial inclination of the spindle 7 without angular movements of the large workpiece.

Fig. 8 shows a three-axis portal milling machine with a vertical spindle. In Fig. 8, the following lines are newly marked: lines 44 carrying the MT mass group 21 on the MW mass group 20, lines 45 carrying the MW mass group 20 as well as the MT mass group 21 moving there, portal 46, movable in the basic machine coordinate axis, the linear motor 47 as the actuator of the relative feed of the tool system 6.7.7 and 10 relative to the portal 46 and the guards 48.

The machine of Fig. 8 is an example of using twin linear motors 39 exerting two accelerating forces between a machine group carrying a MW mass and a machine group carrying a mass MT thereon. Also, the relative position measuring devices 38 associated with each of the two linear motors are doubled. By doubling the motors and their respective encoder systems, a pair of parallel positioning motors is formed

15 systems for eliminating the partitioning of the portal 44, whose two guides 13 on the sliding table 4 with the horizontal clamping surface are far apart. The resulting acceleration force acts in this arrangement approximately midway between the guides 13, i.e. near the center of gravity of the mass MT, which is also beneficial in terms of reducing the transverse in the guide 13. The guiding in the x-axis is different in this machine. of the examples where both the tool and workpiece-bearing machine groups were guided on a fixed part of the frame. In the machine according to FIG. 8, the machine group carrying the MW weight workpiece is guided by a guide 17 on the stationary machine part 2 and only the guide 13 for the machine group carrying the weight MT is placed on it. Since the accuracy of the relative movement of the tool and the workpiece depends mainly on this arrangement, this arrangement is in principle more accurate. In this arrangement, errors in the guide 17 do not affect the workpiece. The relative drive actuator 45 shown here in the form of a linear motor shifts the tool system 6, 7, 8 and 10 in the transverse direction y relative to the portal 44. The guards 46 prevent the operator from accessing the moving machine groups 20 and 21.

Fig. 9 shows a five-axis gantry milling machine in which the seismic balancing according to the invention is applied in two mutually perpendicular coordinate directions. The first coordinate direction continues to mean the seismic balanced basic coordinate axis described so far. The second coordinate direction is the coordinate axis, which is only seismically balanced in addition to the already balanced axis of the first coordinate direction. The designation of the axes with the letters x, y or the designation of the axes as longitudinal or transverse is not relevant to the invention. Most of the machine parts in Fig. 9 of the machine are identical to the machine in the preceding Fig. 8. In addition, Fig. 9 indicates: cross plate 47 having a mass of 3 m 3 movable in the second coordinate direction; the cross plates and the second coordinate direction correction device actuator 50.

The machine of Fig. 9 is an example of applying a device according to the invention for seismic balancing in two perpendicular coordinate directions: in the first coordinate direction of the longitudinal horizontal axis x and in the second coordinate direction of the transverse horizontal y axis. Both machine groups are supported on a support device which allows their sliding movements in both coordinate directions, but does not permit their angular movements with respect to the stationary base part 2. In the examples described below, the support device is shown as a cross plate 47 having a mass of 3 m between the stationary base part 2 and the movable machine assembly 20 carrying a workpiece of weight fc · fc fc fc fc fc

• · fc fcfc · fcfcfc

9911

16MW, however, another type of support device meeting the above requirements may be used without departing from the scope of the invention. The cross plate 47 is moved along the stationary base part 2 in the guide 48 of the second coordinate direction, and on it the guide group 20 carrying the workpiece is moved on the guide 17 in the first coordinate direction. The sliding movement of the cross plate 47 in the second coordinate direction is measured by the metering device 49 and corrected by the actuator 50 of the correction device.

To illustrate the principle of seismic balancing in two coordinate directions, in FIG. 9, the machine unit 20 with a total mass MW is divided into a carrier 51 of a workpiece system "ma" which forms the table body 4 and a workpiece system 52 with a total mass "mb". For example, a turntable 25, a turntable guide 26 and a workpiece

5. Similarly, the machine group 21 with the total mass MT is divided into the carrier 53 of the tool system of the mass mc, formed here by the portal 44 and the tool system 53 of the mass md, formed of the bodies 6, 7, 28, 10 and 8. thus:

MW = ma + mb and also: MT = mc + md

The name "workpiece system" was chosen because, in addition to the workpiece itself, this part may contain other mechanisms that derive, in particular, movements in other, seismically unbalanced coordinate sliding and rotary axes. The workpiece can be, for example, a rotary table or a rotary and tilting table. Similarly, the "tool system" can be a vertical feed of the tool spindle or a swivel and tilt spindle mounted in the rotary and tilt spindle heads.

Seismic balancing in the first, longitudinal direction works the same as in the machine of FIG. 8. MW and MT are brought closer together and delayed by the acceleration forces and equally large counter-directional forces exerted by the twin linear motors 39 acting between the machine group 12, 8, 10, 28, 7 and 6 with a total mass MT and group 61, 73 with a total mass MW.

Seismic balancing in the second coordinate direction works on the same principle as in the first coordinate direction. The actuator 45 of the second coordinate direction moves with its actuating force a tool system 54 having a total mass md along the line H and with an equally high reaction force.

- 17 moves a group consisting of a tool system carrier 53, a workpiece system carrier 51, a workpiece system 52 and a cross plate 47 having a total weight (mc + m + mb + m 3) in opposite directions. As with the first coordinate direction, the equation of acceleration forces is equal to the ratio of acceleration and strokes of the two masses inversely proportional to the ratio of their total masses and the relative acceleration and relative position of both groups will be the sum of their partial accelerations and movements.

The coordinates of the common center of gravity of all participating masses ma, mb, mc, md and m3 do not practically change during their movement in both coordinate directions, since in addition to the friction in guides 17 and 48, only internal accelerating and cutting forces act between the moving masses. For the same reason, shocks to the ground from movements in both seismic balanced coordinate directions practically disappear. The vertical movements of the tool 6, the spindle 7, the tilting spindle head 28 and the vertically displaceable carrier 8 remain seismic unbalanced, but due to the minimum weight of these movable groups and the vertical direction of the accelerating forces the induced impacts are quite harmless.

Giant. 10 shows an alternative embodiment of the machine of FIG. 9 in which the tool system carrier 53 is guided on a cross plate 47.

Fig. 11 is an axonometric view of the generalized machine of Fig. 9, seismic balanced in two coordinate directions, showing the acceleration directions of the masses ma, mb, mc, md, and m3 by the actuators 22 and 45. Actuator 22 acting in the first coordinate direction may act simultaneously with the actuator 45 acting in the second coordinate direction.

The first coordinate direction actuator 22 interposed between the workpiece system carrier 51 and the tool system carrier 53 generates counter-directional, equally large action and reaction forces that are transmitted via the slide guides H and 48 to the tool system 54 and the workpiece system 52. Similarly, between the tool system 54 and the tool system carrier 53, it exerts counter-directional action and reaction forces in the second coordinate direction, one acting only on the tool system 54 and the other being transferred from the tool system carrier 53 via sliding guides 13 to the workpiece system carrier 51. on the one hand to the workpiece system 52 and on the other hand via the guide 17 to the cross plate 47. The described transmission of forces through the guides 13 and 17 allows

- 18 traversing movements in the first coordinate direction always occur in a direction perpendicular to their direction of movement, so that the guide is a very rigid connection for the transmission of forces in the second coordinate direction. The dotted arrows show the directions of spatial accelerations of bodies of masses ma, mb, mc, md and m3 induced by the simultaneous application of the compressive forces of the two displacement actuators 22 and 45. The directions of spatial accelerations will be opposite.

Giant. 12 shows the function of the correction devices in a machine balanced in two coordinate directions. In order to better illustrate the operation of the individual sliding guides and the cross plate 47, a hydrostatic design of the machine guides 11, 13, 17 and 48 and the cross plate are shown. Referring now to FIG. 11, the metering device 55 for relative movement of the tool system 54 relative to the carrier 53 in the second coordinate direction and the calculation block 56 of the common position center of gravity signal Dy for the second coordinate direction are newly designated.

The correction device for the first coordinate direction comprises a position and acceleration detector 85, a calculation block 87 and an actuator 44. The position and acceleration detector 85 repeatedly measures the position of the workpiece carrier 79 relative to the position of the cross plate 75 and performs an acceleration detection. From this data, the computing block 87 calculates the deviation of the common mass center of gravity ma, mb, mc and md from the desired position while the machine is running, and controls this deviation signal to control the deviation of the common mass center of gravity ma, mb, mc and md was minimal in the first coordinate direction.

The position and acceleration data of the masses ma and mb of the machine group carrying the workpiece are obtained by means of a metering device 29 and evaluated by means of a calculation block 24 which controls the operation of the actuator 23 of the correction device for the first coordinate direction. The metering device 29 together with the relative mass feed metering device 38 thus provides the data necessary to digitally control the relative positions of the MW and MT masses as well as the position correction of their common center of gravity ma, mb, mc and md in the first coordinate direction.

The position and acceleration data of the cross plate 47 is obtained by the metering device 49 and evaluated by a calculation block 55 which controls the operation of the correction device actuator 50 for the second coordinate direction. The position and acceleration of the cross plate 47 are identical to the position and acceleration of the ma, mb and mc masses in the second coordinate direction and therefore 0 · 0 · 0 · 0 000 00 0000

The 19-metering device 49 together with the measuring device 55 of the relative displacement of the tool system 54 relative to the masses (mc. Mb, ma and m3) provides the data needed for numerical control and for correcting the position of the common mass center of mass ma, mb, mc, md and m3 in the second. coordinate direction.

The data of the metering systems 28, 29, 38, 49, 30 and 55 may be supplemented by data from accelerometers or other sensors for determining or correcting the position of the common center of gravity in one or both coordinate directions without departing from the scope of the invention.

From the examples given, the possibilities of different designs of seismic machine guides balanced in the first or in the first and second coordinate directions are obvious. Giant. 13 shows basic variants for a simpler case of seismic balancing in the first coordinate direction. The tool system carrier 53 always carries the tool system 54, and the workpiece system carrier 51 always carries the workpiece system 52. The workpiece system 52 and the tool system 54 may include further, seismic unbalanced displacement and rotary coordinate axes. Fig. 13 shows the following guide variants: the tool system carrier 53, each carrying the tool system 54 and the workpiece system carrier 51, each carrying the workpiece system 52 are separately guided in the first coordinate direction on the stationary base part 2. On the stationary base part 2 a tool system carrier 53 is guided and a workpiece system carrier 51 is guided thereon. A carrier 51 of the workpiece system is guided on the stationary base part 2 and on it a carrier 53 of the tool system is guided.

Giant. 14 shows the following four basic variants of machine guidance, seismically balanced in the first and second coordinate directions: the tool system carrier 53, each carrying the tool system 54 and the workpiece system carrier 51, each carrying the workpiece system 52. The workpiece system 52 is moved in the second coordinate direction along the support 51 of the workpiece system. The tool system carrier 53, each carrying the tool system 54 and the workpiece system carrier 51, each carrying the workpiece system 52, are separately guided in the first coordinate direction on a cross-plate 47 supporting device which is always guided in the second coordinate direction to the stationary base parts 2. The tool system 54 is moved along the carrier 53 of the tool system in the second coordinate direction. A carrier 53 of the tool system is guided on the cross plate 47 and on it a crossbar 47 is provided.

The carrier 51 of the workpiece system is guided. The workpiece system 52 is moved in the second coordinate direction along the workpiece system carrier 51. A carrier 51 of the workpiece system is guided on the stationary base part 2 and on it a carrier 53 of the tool system is guided. The tool system 54 moves in the second coordinate direction along the tool system carrier 53

Industrial applicability

Seimically balanced production machine tools according to the invention can be used well where precise numerical control of large masses at high velocities and accelerations is required. This is the area of today's high-speed machine tools with rapid feed dynamics. These machines are now increasingly equipped with linear direct drives, whose maximum feed force is a limiting parameter, especially for larger machines. Reducing the requirement for feed acceleration forces resulting from the seismic balancing principle of the invention means extending the application possibilities of high-speed machine tools to the area of larger and heavier workpieces. The principal elimination of impacts to the foundations according to the invention is no less important contribution to solving the requirements of high precision at high accelerating and braking forces in the feed drives of these machines.

Claims (12)

PATENT CLAIMS A production machine, in particular a machine tool, in which a tool is moved relative to a workpiece by mutual movement, comprising a stationary base part and at least one machine group with support systems for at least one workpiece and at least one other machine group with support systems for at least one tool. that one machine group (20) with a total mass of MW consisting of a workpiece system (51) with a mass of ma and a supported workpiece system (52) with a mass of mb for at least one workpiece and another machine group (21) with a total mass of MT comprising a tool system support (53) of mass mc and a tool system (54) supported thereon having mass md for at least one tool are displaceably mounted relative to the stationary base part (2) at least in the first coordinate direction and connected to each other by at least one action a displacement drive member (22) for controlling their relative position at least in a first coordinate direction independently of the position occupied by their common center of gravity and mass MW MT relative to the stationary base part (2). Production machine according to claim 1, characterized in that at least one of the machine groups (20), (21) is provided with a first coordinate direction correction actuator (23) and a calculation member (24) associated therewith to maintain a common position deviation the center of gravity of the masses MW and MT from the required position of this center of gravity in the first coordinate direction within specified limits while the machine is running. Production machine according to claims 1 and 2, characterized in that the correction device actuator (23) is provided with a calculation element (24) for repeated evaluation of the aw / at ratio of the actual accelerations of the MW and MT masses. weight. Production machine according to claims 1 and 2, characterized in that the machine groups (20) and (21) of the masses MW and MT are movable in two coordinate directions and are supported on a support device to eliminate their angular movements relative to the stationary basic parts (2). -225. Production machine according to claim 4, characterized in that the support device for eliminating the angular movements of the machine groups (20) and (21) relative to the stationary base part (2) is designed as a cross plate (47) weighing m3, guided in the second coordinate direction a sliding guide (48) on the base stationary part (2) and provided with at least one sliding guide for moving at least one of the machine groups (20), (21) in the first coordinate direction. Production machine according to claims 1, 2 and 4, characterized in that the tool system (54) of mass md is displaceably guided in the second coordinate direction on the tool system carrier (53) of mass mc and is connected thereto by a displacement actuator (45) for counter-directional action and reaction forces in the second coordinate direction between the tool system (54) of mass md and the other members (53), (52), (51) and (47) of masses mc, mb, ma and m3 which, like the tool system (54), are displaceably mounted relative to the stationary base part (2) in the second coordinate direction. Production machine according to claims 1, 2 and 4, characterized in that the workpiece system (52) of mass md is displaceable in the second coordinate direction on the workpiece system (51) of mass of mc and is connected thereto by a displacement actuator (52). (45) for counter-directional action and reaction forces in the second coordinate direction between the workpiece system (52) of mass md and the other members (51), (53), (54) and (47) of masses ma, mc, md and m3; which, like the workpiece system (52), are displaceably mounted relative to the stationary base part (2) in the second coordinate direction. Production machine according to claims 1, 2, 4, 5 and 6, characterized in that the cross plate (47) is provided with an actuator (50) of the second coordinate direction correction device and associated calculation member (56) for maintaining the position deviation a common center of gravity of the members (54), (53), (52), (51) and (47) of a total mass (md + mc + mb + ma + m3) from the desired center of gravity position machinery. • · · · -239. Production machine according to claims 1, 2, 4 and 5, characterized in that the workpiece system carrier (51) and the tool system carrier (53) are displaceably supported on the cross plate (47) in the first coordinate direction in at least one guide. Production machine according to claims 1, 2, 4 and 5, characterized in that in the first coordinate system the workpiece system carrier (51) is displaceably supported in at least one guide on the cross plate (47) and the tool system carrier (53) is in the first coordinate direction, it is displaceably supported in at least one guide on the support (51) of the workpiece system. Production machine according to claims 1, 2, 4 and 5, characterized in that the tool system carrier (53) in the first coordinate system is displaceably supported in at least one guide on the cross plate (47) and the workpiece system carrier (51) is in the first coordinate direction, it is displaceably supported in at least one guide on the tool system carrier (53). Production machine according to claims 1 and 2, characterized in that the machine group (20) and the other machine group (21) are displaceably supported relative to the stationary base part (2) only in the first coordinate direction, wherein the workpiece system carrier (51) and the tool system carrier (53) in the first coordinate direction is displaceably supported in the at least one guide on the stationary base part (2). Production machine according to claims 1 and 2, characterized in that the machine group (20) and the other machine group (21) are displaceably supported relative to the stationary base part (2) only in the first coordinate direction, wherein the workpiece system carrier (51) is slidably mounted in the at least one guide on the stationary base part (2) and the tool system carrier (53) is slidably mounted in the at least one guide on the workpiece system carrier (51). Production machine according to claims 1 and 2, characterized in that the machine assembly (20) and the other machine assembly (21) are displaceably supported relative to the stationary base part (2) only in the first coordinate direction, wherein the tool system carrier (53) is displaceably mounted in at least one guide on the stationary base part (2) and the workpiece system carrier (51) is displaceably mounted in at least one guide on the tool system carrier (53).