DE9115369U1 - Robot drive device based on the Cartesian principle for multi-axis, spatially arranged transport systems, in particular for NC linear axes - Google Patents

Description

Prof. Dr.-Ing. Werner Weinert Eichköpfelweg 9 6101 Modautal

07.12.1991

Robot drive device based on the Cartesian principle for multi-axis, spatially arranged transport systems, in particular for NC linear axes

The present invention relates to a robot drive device based on the Cartesian principle, which makes it possible to reduce the control effort and the number of drive motors overall, which are very high in known, correspondingly large systems. System, operating costs and technical functionality must be taken into account here!

The invention considers computer-controlled work machines for handling techniques, for example for loading, assembly and sorting processes, which have transport and/or gripping devices. In all of these cases, a work point moves on a precisely defined path in space. Depending on the robot application, various tools can be used as the work point, such as grippers, welding and riveting tools, foam, adhesive and spray nozzles, etc., to name just a few.

The present invention relates to the following prior art:

Depending on the spatial path of the working point, a point, line or path control is selected as the robot control, whereby the Cartesian principle is applied.

With the simplest control, point control, only the positions of the working point are important, not the distances between them. Point control is mainly used for positioning tasks in one plane, such as for assembly, placement or picking of parts.

In route control, in addition to the end points of the route to be traveled, the guidance accuracy along this route is also required. The route itself is based on the structure of the robot and is not arbitrarily defined in the working plane.

Path controls are used for free paths or arbitrarily curved paths in space. An example of such an application is the painting of a curved car body, where, for example, the "spray nozzle" working point must be moved at a constant distance and always at a certain inclination to the surface.

In order to be able to program the paths of the working point in the manner described, robots are usually built modularly from individual axes. Each unit has a controllable motor and a mechanism for executing the movement. The higher-level control of the individual drive motors is carried out by a robot program, whereby the individual axes are kinematically coordinated in such a way that the working point ultimately describes its path correctly.

In the Cartesian robot system, the individual mechanical axis modules are set up orthogonally to one another in a plane (e.g. X and Y) so that all positions within this X-Y area can be approached with the vertical axis Z, which, for example, carries a gripper as a working point. When selecting the units, linear modules are used for the X and Y axes, which can be structurally adapted to one another, with each linear module having its own drive motor that drives a transport device (threaded spindle or toothed belt) and to which a carriage (support) is attached. This is moved linearly, i.e. straight, along the guide profile of the axis module.

The terms "linear unit", "linear axis" or "linear drive" are also used in the literature for such mechanical linear motion devices. NC linear axes have now reached a high technical level and are mainly used in the handling sector. Of the many patent documents, reference should be made to DE 3839091 Al, which describes the mechanical structure of such a unit.

If a second complete linear unit is attached to the first slide and the second slide of the second unit is equipped with a suitable gripper, it can move to any position within the plane formed by the two linear modules (X and Y). For reasons of strength and for the purpose of greater positioning accuracy, Cartesian systems are constructed symmetrically, e.g. from two parallel X-linear axes that are bridged by the Y-linear axis. This leads to the well-known portal design. In the specialist magazine AGT Documentation 2, June 89, on page 34, such a three-axis, Cartesian portal system constructed from linear axes is shown. The task here is to supply and remove parts from machine tools.

If the path control is used for Cartesian robots, the defined travel path is always along a linear axis, and the remaining axes (e.g. Y-axis) are blocked during this movement.

All NC controls can be used on all types of robots, including Cartesian ones, whereby the universal path control includes line and point control. NC stands for "Numerically Controlled" and means the computer-aided connection of the axes.

For special and complicated robot tasks, pure positioning control of the working point is usually not sufficient; additional axes are often added as auxiliary and main axes, which are required to control the robot peripherals or complex gripper systems. Depending on the number (n) of controllable axes, one therefore speaks of n-axis systems; in the case of two axes, of two-axis robot controls.

For the single-axis case of an NC control, the user informs the internal control computer (CPU) of the required parameters (position, speed, acceleration, accuracy and peripheral inputs/outputs). The CPU (Central Processing Unit) causes the servo controller of the control to generate coded data signals for the travel speed. A servo amplifier, which is part of the power section, amplifies the analog controller signal and passes it on to the drive motor, e.g. of a linear axis. In the

In the servo motor, the rotational speed is recorded by an integrated tachometer and the number of revolutions and thus the position of the operating point is recorded by an integrated rotary encoder and reported back to the servo controller for a target/actual comparison. In addition, limit switches send their signals to the input/output card of the control when the carriage leaves its permitted travel range. The linear unit is "zeroed" with a reference switch, which is to be understood as a special limit switch, i.e. the position mark of the operating point is calibrated to zero. Finally, all modern process controls can be linked to computer networks so that the local robot controls (slaves) can receive their signals directly from a higher-level master computer (host). This also requires another control module. As with the structure of the associated mechanics, there are modular structures for controls with terms such as "single-axis positioning control", "three-axis path control". For simple handling tasks, it is preferable to use so-called programmable logic controllers (PLCs) depending on the number of axes, which have all of the previously mentioned components for each axis.

The advantages of modern NC controls for driving robot axes described above must also be compared with the economic side and the disadvantages listed below.

As a practical analysis shows, the costs of using a programmable logic controller to position a linear unit are:

Positioning control (PLC) 50% Mechanics (timing belt drive) 20 '/. Adaptation (proportionate) 10% Drive motor (DC servo motor,
Encoder, speedometer) 20% total cost 100 '/.

For each NC linear unit, 70'/. is allocated to the control, including the drive motor and only 30*/. to the mechanical movement part. Since - as described - robot systems are built with at least two axes, the shares add up accordingly.

At present, the heavy drive motors in two-axis systems all have to be moved. This means more drive energy is required and the robot design is stiffer and therefore heavier. In EP 0 329 642 Al, the drive motor for the second (Y) axis is arranged stationary for a three-axis storage and retrieval machine (X, Y and Z) in order to reduce the masses that travel with it, and its carriage is moved via a second drive belt. However, each linear unit still has its own motor and its own drive control. These known arrangements are complex in terms of construction and control technology and are therefore very expensive.

In order to overcome these disadvantages of the prior art, the present invention has the object of creating a robot drive device according to the Cartesian principle for multi-axis, spatially arranged transport systems, in particular NC linear axes, in which modularly constructed robot systems each require only one drive motor and one drive control.

The invention relates to robot systems based on the Cartesian principle, whereby the known, toothed belt-driven linear axes are used and the robot drive device according to the invention can be adapted to the known linear axes, so that the movement is possible intermittently by only one drive motor.

Furthermore, in addition to point and line control, diagonal travel of the operating point should also be able to be simulated as "quasi-path control". This is evident from the drawings in conjunction with Tables 1 and 2.

This task is solved by a robot drive device based on the Cartesian principle in accordance with the description, the drawings and the claims.

The invention is explained below with reference to drawings, showing an embodiment in which two linear axes of a Cartesian system in the X-Y plane are moved by only one drive motor.

It shows:

Fig. la: a representation of a Cartesian robot system in the X-Y plane for orthogonal directions of travel; as well as the corresponding switching matrix according to Tab. 1,

Fig.Ib: a section I-I according to Fig. la,

Fig. 2: a perspective view in partially cut-open condition of a toothed belt-driven linear single axis according to the state of the art with flanged brake element,

Fig. 3 : a representation of a Cartesian robot system in the X-Y plane for orthogonal and diagonal directions of travel; as well as the corresponding switching matrix according to Tab. 2 and

Fig. 4: a partial section II-II according to Fig. 3 in an enlarged view.

According to the invention, the Cartesian robot drive device is driven by only one drive motor with its directions of rotation according to the double arrow 1.1, which receives the movement signals and travel commands from only one drive control. In the Cartesian application, which can still be constructed from known linear units, the individual axes are designed in such a way that a drive belt can be moved within the individual axes. This requires suitable toothed belt pulleys and functional elements in the slides, which are designed as clutches or brakes and cause the slides to be driven or blocked, as shown in the drawings. The drive control works intermittently, since the individual travel distances (X and Y) are covered one after the other in accordance with the travel commands sent.

When the operating point 4.4 moves along the X-axis, the coupling elements K _x or Kv and the braking elements B _x or Bv are controlled via the input/output signals of the control system in accordance with a created switching matrix so that only the first carriage 3 can be moved in the X direction by the double-sided toothed belt 5.2, and the second carriage 4, which has the operating point 4.4, e.g. in the form of a gripper, is braked. Analogously, for the movement of the second carriage in the Y direction, the coupling elements K and the braking elements B are switched differently so that the distance communicated to the drive motor is now used to change the Y position of the operating point. In this way, the operating point 4.4 describes an orthogonal step-shaped line, although the step shape can of course be preselected by the robot program.

For diagonal travel of the working point 4.4, the Cartesian structure is supplemented according to the invention by a second toothed belt 5.3, which is parallel to the first linear unit 1 and is constantly moved like the first double-sided toothed belt 5.2. By means of additional coupling elements, the synchronous movement of the first carriage 3 and the second carriage 4 in different directions is also possible in order to achieve a polygonal quasi-path control.

In Fig. la a system is shown that consists of the horizontally running first linear unit 1 for the X-movement of the first slide 3 and a second linear unit 2 attached vertically to the first slide 3 for the Y-movement of the second slide 4 and thus the working point 4.4. The drive motor turns a first toothed belt pulley 1.2. A double-sided toothed belt 5.2, which is laid in the first linear unit and in the second linear unit 2, drives the other toothed belt pulleys, namely the second toothed belt pulley 1.3, the fifth toothed belt pulley 2.2 and the sixth toothed belt pulley 4.3 and is deflected by means of the first toothed belt deflection pulley 3.1, the second toothed belt deflection pulley 3.2, the third toothed belt deflection pulley 4.1 and the fourth toothed belt deflection pulley 4.2. The working point 4.4 moves in the X-Y plane within its working area.

— O _

4.5 only if the first carriage 3 or the second carriage 4 is coupled to the double-sided toothed belt 5.2 or locked to the first guide profile 1.4 or to the second guide profile 2.4 via certain functional elements, namely K (clutch) and B (brake) in accordance with the drawings and Tables 1 and 2.

The functional elements (K or B) are, according to Fig. 1b and Fig. 2, commercially available, single-acting, pneumatic short-stroke cylinders 6, which are controlled by a solenoid valve, in which a piston 6.1 in a housing 6.2 is pressed against a compression spring 6.4 when compressed air is applied via the compressed air bore 6.3. To reinforce the coupling/braking effect, the piston rod of the piston 6.1 can be coated with a lining.

6.5.

The linings 6.5 of all brake and coupling units can be designed for friction or positive locking depending on the application. While a friction lining is produced by vulcanizing profiled hard rubber, a positive locking is achieved in the case of the toothed belt deflection pulleys by means of corresponding radial micro-toothing on the third effective surface 3.1.1 of the first toothed belt deflection pulley 3.1 and on the fourth effective surface 4.1.1 of the third toothed belt deflection pulley 4.1. For the linear braking surfaces, the first effective surface 1.4.1 of the first guide profile 1.4 and the second effective surface 2.4.1 of the second guide profile 2.4 can be equipped with corresponding linear micro-toothing on which the counter profiles of the lining 6.5 can be locked. The lining 6.5 can be designed as a friction lining or with micro-toothing. The selection of the different active surface pairings then causes either a positionally precise positive locking or a frictional locking which is more suitable for lower requirements.
In the depressurized state, the spring force acts and exerts the arrow

6.6 applies the spring force for coupling (K) or braking (B) to the correspondingly assigned effective area.

The first carriage 3 and the second carriage 4 each have two such functional elements, one coupling element K and one braking element B. In relation to the two axes X and Y, the functional elements K _x , K _v , B _x , B _v are obtained accordingly.

While the first carriage and the second carriage 4 are selectively locked to the first effective surface 1.4.1 of the guide profile 1.4 or to the second effective surface 2.4.1 of the second guide profile 2.4 with the braking elements B (B _x and B _v ), the first toothed belt deflection pulley 3.1 or the third toothed belt deflection pulley 4.1 can be coupled with the coupling elements K (K _x and K _Y ); ie they can be blocked relative to the first carriage 3 or relative to the second carriage 4.

This has the effect that the double-sided toothed belt 5.2 can no longer move at this point due to the blocked first toothed belt pulley 3.1 or the blocked third toothed belt pulley 4.1 (third effective surface 3.1.1 with lining 6.5 or fourth effective surface 4.1.1 with lining 6.5), and the corresponding slide 3 or 4 is carried along by the double-sided toothed belt 5.2.

Depending on the switching state (1 = coupled/braked, 0 = not coupled/not braked) of the short-stroke cylinder 6 (functional elements K or B), various movement options of the operating point 4.4 result according to Table 1 in relation to Fig. 1. Of the total of 2.'* = 16 possible combinations, only a few selected ones are suitable for the consistent operation of the robot system.

In Tables 1 and 2 of Drawings 1 and 3, the vertical dimensions are as follows:

No.

K:

Ki

8 : Switch combination number ,—K: Coupling element
B: Brake element
Indices: X : X-direction Y : Y-direction

1 : X-direction forward

2 : X-direction backwards

and the numbers "0" or ^M l

There

0 : Clutch is not set (not coupled)

or

Brake is not set (not locked)

1 : Clutch is set (coupled)

or

Brake is set (locked)

In the case of travel along the X axis for constant Y, in order to drive the first carriage 3 (No. 1 in Table 1), the first toothed belt deflection pulley 3.1 must be coupled using the coupling element K _x and the brake B _x of the first carriage 3 must be released. The second carriage 4 must be blocked on the second guide profile 2.4 of the second linear unit 2 via the brake B _v in order to position the working point 4.4 with respect to Y. Since the double-sided toothed belt 5.2 does not move in the area of the third toothed belt deflection pulley 4.1, the sixth toothed belt pulley 4.3, the fourth toothed belt deflection pulley 4.2, the fifth toothed belt pulley 2.2 and the second toothed belt deflection pulley 3.2 due to the coupling of the first toothed belt deflection pulley 3.1, the coupling unit K _v does not need to be engaged. For the movement of the operating point 4.4 along the Y-axis at constant X, switching state no. 2 applies according to Table 1; ie coupling unit K _x released, brake B _x set, coupling unit K _v locked to drive the second carriage 4, third toothed belt deflection pulley 4. 1, brake B _v released.

If the working point 4.4 in its XY working area 4.5 is to be moved between two points (Xi,Yi) and (X ₂ ,Y _£ ) by only one drive motor, this can be done in a step-like manner via a control program, e.g. a programmable logic controller (PLC), whereby the geometry of the steps can be selected as desired.

If - as is usual for point controls - only the end position is important, the drive motor is controlled "with a staircase" as follows:

old coordinates (start): X ₁ , Y ₁

new coordinate (target) : X,=.· = DX + X ₁ for Y ₁ = const.

Ya> = DY * Y ₁ for X _£: = const.

with the relative travel distances: DX = X ₁ ^ - X ₁

DY = Ys - Y ₁ .

Before the next travel command, the reached target coordinates (Xe, Ye.) are declared as the starting value (X ₁ , Y ₁ ), the relative travel distances (DX, DY) are recalculated and the new absolute coordinates X ₂ and Y ₁ ^- are approached.

The calculation and design of the travel course (also along small individual steps) is carried out by control programs that allow individual adaptation to the respective application. The control of the functional elements K and B is achieved internally in the program by setting PLC outputs, with the effect that the various solenoid valves for the four pneumatic short-stroke cylinders 6 required here are attracted according to the switching matrix in Table 1.

In the case of the point control described, the kinematic movement sequence of the first carriage 3 and the second carriage 4 is intermittent, since there is only one drive motor, which is first controlled with the command sequence for X taking into account the switching state no. 1 according to Table 1 and then with the corresponding command sequence for Y according to no. 2 of Table 1. When the switching state changes, the old position registers for X and Y must be saved within the program, since they must be able to be called up again shortly afterwards in order to calculate a new position.

The structure of a Cartesian two-axis robot system shown in Fig. 1a and Fig. 1b is based on linear units according to Fig. 2, which have to be modified due to the changed belt guide.

In an unmodified, exemplary form, according to Fig. 2, each first linear unit 1 consists of a drive motor that rotates the first toothed belt pulley 1.2. This drives a first toothed belt 5.1, which is attached to a support 1.7 by means of a clamping screw 1.5 and a clamping piece 1.6. The second toothed belt pulley 1.3 required for the belt return is, like the first toothed belt pulley 1.2, mounted in the first guide profile 1.4, on which the support 1.7 can also be moved linearly back and forth. In Fig. 2, the support 1.7 encloses the first guide profile 1.4 in a U-shape; the representation of a roller bearing between the support 1.7 and the first guide profile 1.4, which is usual for this application, has been omitted.

For better clarity, Fig. 2 shows a flanged brake element B _x based on a commercially available pneumatic short-stroke cylinder 6 with piston 6.1, housing 6.2, compressed air bore 6.3, compression spring 6.4 and friction lining 6.5. If the brake B _x is set, frictional or positive locking with the first active surface 1.4.1 of the first guide profile 1.4 occurs - as described above.

Within the scope of the invention, the support 1.7 is now structurally modified to form the first slide 3 or the second slide 4 in that, according to Fig. 1 (or Fig. 4), an upper slide guide 3.3 and a lower slide guide 3.4 are attached to a connecting plate 3.5, to which, in the one-dimensional case, workpiece carrier structures, grippers or a second linear unit according to Fig. la or Fig. 1b can be mounted.

In combination with a second linear unit 2, the first carriage 3 of the first linear unit 1 is further modified according to Fig. 1a and Fig. 1b so that a first toothed belt deflection pulley 3. and a second toothed belt deflection pulley 3.2 are mounted, via which the modified guidance of the double-sided toothed belt 5.2 is carried out. Furthermore, the first carriage 3 is adapted: the second linear unit 2, which is perpendicular to the first, and the functional elements for coupling K _x and braking B _x . The structure of the second linear unit 2 corresponds to that of the first linear unit. The second carriage 4 of this second linear unit 2 contains, in addition to the third toothed belt deflection pulley 4.1 and the fourth toothed belt deflection pulley 4.2, a further sixth toothed belt pulley 4.3 for driving further axes (e.g. Z axis).

In the illustrated embodiment according to Table 1 and Fig. la and Fig. 1b, in order to implement No. 3, the first carriage 3 and the second carriage 4 must be locked using their brakes B _x and _BY . The drive 1.1 now drives the double-sided toothed belt 5.2 unhindered, with the result that the sixth toothed belt pulley 4.3 also rotates. From this rotation, further movements can be derived to drive a third axis, as well as further belt or threaded spindle drives. However, these are measures familiar to the expert and are not shown in the drawings.

As the switching matrix Table 1 and the previous explanations show, the operating point 4.4 can only be moved orthogonally along the X or Y axis within its working area 4.5. This represents the classic path control. Diagonal movement of the operating point 4.4 along X and Y at the same time is not possible.

To achieve this, according to Fig. 3 and Fig. 4, a further belt drive must be added to the first linear unit 1, which consists of a third toothed belt pulley 1.8, a fourth toothed belt pulley 1.9 and a second toothed belt 5.3. This second belt drive is arranged parallel to the belt drive according to Fig. 1 (consisting of first toothed belt pulley 1.2, second toothed belt pulley 1.3 and double-sided toothed belt 5.2) according to Fig. 4 (= side view of Fig. 3) and is positively connected to it via a first key 1.10 and a second key 1.11.

The drive motor therefore also drives the second toothed belt 5.3, the upper and lower strands of which have opposite directions. If the first carriage 3 is now coupled to one of these strands, it is driven in the corresponding direction. The drive is provided by two further functional elements Ki and K^, which like all of them are constructed as short-stroke cylinders 6. The lining 6.5 of the piston rod of the piston 6.1 clamps the second toothed belt 5.3 and thus creates the necessary frictional coupling with the first carriage (3). The first carriage 3 has an upper carriage guide 3. and a lower carriage guide 3.4, which are fastened to a connecting plate 3.5, to which the housing 6.2 of a brake element B _x is flanged. In Fig. 4, the brake rails 3. 6 in the modified connecting plate 3.5 are used to couple to the second toothed belt 5.3 by means of the two coupling elements Ki and K&. No. 4 in Table 2 shows the implementation of a diagonal movement from bottom left to top right and back (mathematically positive gradient) when the coupling elements Ki and K _v are set. In contrast, No. sets the other diagonal direction from top left to bottom right and back (mathematically negative gradient) when the coupling elements K _fc: and K _v are set.

By expanding to two transport belts, the double-sided toothed belt 5.2 and the second toothed belt 5.3, the double-sided toothed belt 5.2 can be functionally relieved or used for an additional function Z. Numbers 6 to 8 in Table 2 show how additional movements of the sixth toothed belt pulley 4.3 can be generated during travel (X or Y), e.g. to drive a Z spindle (not shown) perpendicular to the drawing plane.

With the 6 functional elements (K _x , B _x , K _Y , B _v , K ₁ , K _a ) 2 ^& = 64 switching states can logically be set, of which many combinations are conceivable but not suitable for operation. The most favorable pairings are those marked up to No.

The programmed movement sequence is again intermittent. The quasi-three-dimensional trajectory of the working point 4.4 is constructed from small line elements in a polygonal manner in the working area 4.5. After each polygon section, the program switches to a new switching state according to Table 2.

A particular advantage of using the present invention is the reduction of the drive control from at least two to just one complete NC control including drive motor. For three-axis robot systems, this results in a halving of the system costs. A further advantage is that the elimination of moving motor masses and the use of a stationary drive motor leads to considerable energy savings and significantly lighter robot designs.

Overall, the mode of operation of the invention can be made clear using the following list:

B _x brakes connecting plate 3.5 on first guide profile 1.4, so that the first carriage 3 is fixed to the first linear unit 1;

Bv brakes the second carriage 4 on the second guide profile 2.4, so that the second carriage 4 is fixed to the second linear unit 2;

Kx couples the first toothed belt pulley 3.1, so that the first carriage 3 moves along the first guide profile 1.4 as a result of being driven by the double-sided toothed belt 5.2;

&Kgr;&ggr; couples the third toothed belt pulley 4.1, so that the second carriage 4 moves along the second guide profile 2.4 as a result of being driven by the double-sided toothed belt 5.2;

Ki couples the upper brake rail 3.6 of the connecting plate, so that the first carriage 3 moves along the first guide profile 1.4 as a result of being driven by the second toothed belt 5.3 in the X direction;

Ks; couples the lower brake rail 3. 6 of the connecting plate, so that the first carriage 3 moves along the first guide profile 1.4 as a result of being driven by the second toothed belt 5.3 in the opposite X direction.

Within the scope of the invention, two embodiments of the robot drive device are proposed. In both embodiments, the first linear unit 1 for the X-movement and the second linear unit 2 for the Y-movement are arranged perpendicular to one another, with the second linear unit 2 being attached to the first carriage. The difference between the two embodiments according to Fig. 1 a and Fig. 1b on the one hand and the embodiment according to Fig. 3 and Fig. 4 on the other hand is merely that in the embodiment according to Fig. 3 and Fig. 4 an additional second toothed belt 5.3 is arranged.

Fig. 2 merely shows the mode of operation of an NC linear unit with brake, in which a first toothed belt 5.1 is connected to the support 1.7 by means of a clamping screw 1.5 and a braking element B _x mounted on the support 1.7 can brake the support 1.7 itself on the first effective surface 1.4.1.

\&agr; racy

1 first linear unit for the X-movement

1.1 Arrow for direction of rotation of the drive motor

1.2 first timing belt pulley

1.3 second timing belt pulley

1.4 First leadership profile

1.4.1 First effective surface for friction/form locking

1.5 Clamping screw

1.6 Clamping piece

1.7 Support

1.8 third timing belt pulley

1.9 fourth timing belt pulley

1.10 first key

1.11 second key

2 second linear unit for the Y-movement

2.2 fifth timing belt pulley

2. 4 second leadership profile

2.4.1 Second effective surface for friction/form locking

3 first sledge

3.1 first timing belt pulley

3.1.1 Third effective surface for friction/form locking

3.2 second timing belt pulley

3.3 upper slide guide

3.4 lower slide guide

3.5 Connecting plate

3.6 Brake rails of the modified connecting plate

4 second carriage

4.1 third timing belt pulley

4.1.1 fourth effective surface for friction/form locking

4.2 fourth timing belt pulley

4.3 sixth timing belt pulley

4.4 Operating point

4.5 Working area of the working points

5.1 first timing belt

5.2 double-sided timing belt

5.3 second timing belt

&bgr; Short stroke cylinder

6.1 Piston

6.2 Housing

6.3 Pneumatic drilling

6.4 Compression spring

5.5 Coating for friction/form locking

6.6 Arrow for force effect

Coupling and fuel elements

K _w Coupling element for driving the first carriage Ky Coupling element for driving the second carriage Ki Coupling element for driving the first carriage

in positive X direction Ks coupling element for driving the first carriage in negative X direction

B,< Brake element for locking the first carriage B _y Brake element for locking the second carriage

Claims (2)

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Robot drive device based on the Cartesian principle for multi-axis, spatially arranged transport systems, in particular for NC linear axes, characterized in that it has the following features: a first linear unit (1) on which a first carriage (3) is guided so as to be longitudinally movable, to which a second linear unit (2) is fastened, on which a second carriage (4) is longitudinally movable, wherein the second linear unit (2) is aligned perpendicularly to the first linear unit (1), a drive motor which is attached to the first linear unit (1) and drives the first toothed belt pulley (1.2) in both directions according to arrow (1.1), wherein the first toothed belt pulley (1.2) is rotatably mounted at one end of the first linear unit (1) and its shaft is positively connected to that of the drive motor, a double-sided toothed belt (5.2) which is wound around the first toothed belt pulley (1.2), around the second toothed belt pulley (1.3) rotatably mounted on the other end of the first linear unit (1), around the second toothed belt deflection pulley (3.2) rotatably mounted on the first carriage (3), around the second linear unit (2) rotatably mounted fifth toothed belt pulley (2.2), around the fourth toothed belt deflection pulley (4.2) rotatably mounted on the second carriage (4), around the sixth toothed belt pulley (4.3) also rotatably mounted on the second carriage (4), around the third toothed belt deflection pulley (4.1) also rotatably mounted on the second carriage (4) and around the first toothed belt deflection pulley (3.1) rotatably mounted on the first carriage (3), wherein the working point (4.4) on the second carriage (4) is arranged in the center of the sixth toothed belt pulley (4.3), a coupling element K _x in the area of the first toothed belt deflection pulley (3.1), the housing (6.2) of which is fastened to the connecting plate (3.5) of the first carriage (3) and which has a piston (6.1) with a piston rod, a compression spring (6.4) and a compressed air bore (6.3), the end of the piston rod being provided with a lining (6.5) which is designed as a frictional lining or as a surface, radial micro-toothing which cooperates with the third active surface (3.1.1) attached to the first toothed belt deflection pulley (3.1), which also has a radial micro-toothing or a friction lining, a braking element B _x , the housing (6.2) of which is fastened centrally to the connecting plate (3.5) of the first carriage (3) and which has a piston (6.1) with a piston rod, a compression spring (6.4) and a compressed air bore (6.3), the Piston rod with its frictional or positive-locking coating (6.5) acts on a likewise frictional or positive-locking first active surface (1.4.1) which is arranged on the outside of the first guide profile (1.4) and the cooperation of the coating (6.5) with the first active surface (1.4.1) shows a braking effect according to arrow (6.6) of the first slide (3) on the first linear unit (1), a coupling element K _v , the housing (6.2) of which is fastened to the second carriage (4) in the region of the third toothed belt deflection pulley (4.1) and which has a piston (6.1) with a piston rod, a compression spring (6.4) and a compressed air bore (6.3), the end of the piston rod being provided with a lining (6.5) which is designed as a frictional lining or as a surface, radial micro-toothing which cooperates frictionally or positively with the third toothed belt deflection pulley (4.1), the third toothed belt deflection pulley (4.1) having a similarly designed fourth active surface (4.1.1) with radial micro-toothing or a friction lining when they cooperate, - 3 a braking element B _v , the housing (6.2) of which is fastened centrally to the second carriage (4) and which has a piston (6.1) with a piston rod, a compression spring (6.4) and a compressed air bore (6.3), wherein the piston rod with its frictional or positive-locking lining (6.5) acts on a likewise frictional or positive-locking second active surface (2.4.1) which is arranged on the outside of the second guide profile (2.4), and the cooperation of the lining (6.5) with the second active surface (2.4.1) shows a braking effect of the second carriage (4) on the second linear unit (2). 2. Robot drive device according to claim 1 according to a further preferred embodiment, characterized in that it additionally has the following features: a second toothed belt (5.3) arranged parallel to the double-sided toothed belt (5.2) on the first linear unit (1), which is guided over the third toothed belt pulley (1.8) and the fourth toothed belt pulley (1.9), the first toothed belt pulley (1.2) being positively connected to the third toothed belt pulley (1.8) by means of the first key (1.10) and the second toothed belt pulley (1.3) being positively connected to the fourth toothed belt pulley (1.9) by means of the second key (1.11), a coupling element Ki on the modified connecting plate (3.5) of the first carriage (1), which clamps the second toothed belt (5.3) from above onto the upper of the two brake rails (3.6) in accordance with the effect of arrow (6.6) and which, like the previously described coupling elements K _x , K _v and the brake elements B _x , Bv, consists of a piston (6.1), a housing (6.2), a compressed air bore (6.3) and a compression spring (6.4) and a coupling element Ks:, which, like the coupling element K _t, is arranged on the modified connecting plate (3.5) of the first carriage (1), but in mirror image to the coupling element K ₁ and clamps the lower run of the second toothed belt (5.3) from below onto the lower of the two brake rails (3.6) in accordance with the effect of arrow (6.6), wherein the linings (6.5) of the two coupling elements K _x and K^ due to the interaction with the Toothed belts (5.3) are designed with frictional engagement.