Laser processing machine with weight compensation

Abstract

Described is a laser processing machine with a height-adjustable laser component, a height-adjustable machine component, and a weight compensation system. The weight compensation system has at least one roller unit that includes at least two rollers fastened on a common axle and rotatably fixed with respect to one another. The axle is configured to rotate freely and slide in a machine frame guide of the laser processing machine. The laser component is held suspended by a first traction member wound onto the first roller. The machine component is held suspended by a second traction member wound onto the second roller. The first traction member and the second traction member are wound in reverse (opposite) directions onto the rollers. A counterweight device acts on the axle by exerting a counterforce, which compensates, at least partially, for the forces exerted by the laser component and the machine component.

Claims

1. A laser processing machine comprising: a machine frame guide; a height-adjustable laser component; a height-adjustable machine component; and a weight compensation system comprising at least one roller unit, first and second traction members, and a counterweight device; wherein each roller unit comprises a first roller and a second roller fastened on a common axle and rotatably fixed with respect to one another, wherein the common axle is positioned and configured to rotate and slide freely in the machine frame guide, wherein the height-adjustable laser component is held suspended by the first traction member wound onto the first roller, wherein the height-adjustable machine component is held suspended by the second traction member wound onto the second roller, wherein in each roller unit the first traction member and the second traction member are wound in reverse directions onto the first roller and the second roller with respect to one another, and wherein the counterweight device is configured to act on the common axle of each roller unit by exerting a counterforce on the common axle, wherein the counterforce compensates, at least partially, forces exerted respectively by the height-adjustable laser component and the height-adjustable machine component on the common axle in a sliding direction in the machine frame guide.

2. The laser processing machine of claim 1, wherein the counterweight device is configured to act on the common axle of each roller unit by exerting a counterforce on the common axle that completely compensates the forces exerted respectively by the height-adjustable laser component and the height-adjustable machine component on the common axle in the sliding direction in the machine frame guide.

3. The laser processing machine of claim 1, wherein radii R1 and R2 of the first roller and the second roller, respectively, and the counterweight device are selected such that in the idle state no torque is applied to the common axle and no force is applied in the sliding direction to the common axle.

4. The laser processing machine of claim 1, further comprising a deflection pulley configured to deflect at least one of the first traction member and the second traction member, wherein the force of the laser component and the force of the machine component act on the common axle in opposite directions.

5. The laser processing machine of claim 1, further comprising a deflection pulley configured to deflect at least one of the first traction member and the second traction member, wherein the force of the laser component and the force of the machine component act on the common axle in the same direction.

6. The laser processing machine of claim 1, wherein the counterweight device is formed by a counterweight mG suspended on the common axle.

7. The laser processing machine of claim 1, wherein the weight compensation system comprises a pair of roller units, wherein one roller unit is rotatably mounted on each side of the counterweight mG, wherein the common axles of each of the roller units are configured to rotate freely and slide in the machine frame guide, and wherein the pair of roller units is associated with a pair of first traction members wound onto the respective first rollers and a pair of second traction members wound onto the respective second rollers.

8. The laser processing machine of claim 1, wherein the counterweight device comprises at least one of a pneumatic spring and a spring balancer engaging the common axle.

9. The laser processing machine of claim 1, wherein the machine frame guide is aligned vertically.

10. The laser processing machine of claim 1, wherein the machine frame guide is aligned horizontally.

11. The laser processing machine of claim 1, wherein the machine frame guide is aligned obliquely.

12. The laser processing machine of claim 1, wherein each of the first traction members and the second traction members comprise at least one of a cable, a belt, and a chain.

13. The laser processing machine of claim 1, wherein the height-adjustable laser component comprises a laser processing optical system.

14. The laser processing machine of claim 13, wherein the height-adjustable laser component comprises a laser resonator.

15. The laser processing machine of claim 13, wherein the laser processing optical system comprises a deflecting unit and a scanner unit.

16. The laser processing machine of claim 15, wherein the height-adjustable laser component comprises a laser resonator.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a perspective view of a laser processing machine according to the invention.

(2) FIG. 2 is a schematic illustration of the forces applied by the laser processing machine shown in FIG. 1.

(3) FIG. 3 is a schematic illustration of the forces applied by a laser processing machine modified from that shown in FIG. 1.

DETAILED DESCRIPTION

(4) Identical reference numbers have been used for the same or functionally identical components in the following description of the drawings.

(5) FIG. 1 shows a laser processing machine 1. The laser processing machine 1 shown in FIG. 1 is a marking laser work station with a height-adjustable marking laser 2, a height-adjustable protection door 3, and a common weight compensation system 4 for the marking laser 2 and the protection door 3. The weight mL of the marking laser 2 is typically approximately twice that of the weight mT of the protection door 3. For reasons of clarity, drive elements (motors, spindles) and guides of the marking laser 2 and the protection door 3 are not shown.

(6) The weight compensation system 4 comprises a counterweight device 5 in the form of a counterweight mG and two roller units 6, which are rotatably mounted on the counterweight mG, one on each side. Each roller unit 6 comprises two rollers 8, 9 fastened on a common axle 7 in a non-rotatable manner (i.e., configured to rotate together and not to rotate with respect to one another), with different radii R1, R2, wherein the axle 7 is held freely rotatable and can slide in a vertical machine frame guide 10 (sliding direction 11). As shown schematically in FIG. 2, for one roller unit 6, the marking laser 2 is suspended from the smaller rollers 8 by a first traction member 12 wound onto the rollers 8, and the protection door 3 is suspended from the larger rollers 9 by a second traction member 13 wound onto the rollers 9. The two traction members 12, 13 are wound in reverse directions onto the rollers 8, 9 and can be embodied as cables, belts or chains, but are not limited thereto. The two traction members 12, 13 are diverted via deflection pulleys 14 in such a way that the weight force FL of the marking laser 2 acts upon the axle 7 in an upward direction, and the weight force FT of the protection door 3 acts in a downward direction. Counterweight mG suspended from the axle 7 applies a downwardly directed counterforce FG onto the axle 7, which can completely compensate the weight forces applied to the axle 7 in sliding direction 11 by the marking laser 2 and the protection door 3 in an idle state, i.e., FG=FLFT. The radii R1, R2 of the rollers 8, 9 are selected in such a way that no torque is applied to the axle 7 in the idle state, i.e., R1FL=R2FT. In the embodiments illustrated, the marking laser 2 is twice as heavy as the protection door 3, so that the traction member 12 of the marking laser 2 is wound onto the smaller roller 8 and the ratio of the roller radii is R1:R2 approx. 1:2.

(7) The functionality of the weight compensation system 4 is described as follows:

(8) Neither a torque nor a force is applied upon the axle 7 in sliding direction 11 in an idle state, so that the two roller units 6 neither rotate nor move in the sliding direction and the marking laser 2 and the protection door 3 are weight compensated.

(9) If the marking laser 2 is displaced in height, for example lowered by its drive motor, the protection door 3 remains fixed at its height by the self-retention of its non-driven motor. By lowering the marking laser 2, the first traction member 12 is wound onto its roller 8 and the second traction member 13 is wound off its roller 9 (i.e., they are wound in reversed directions with respect to one another), wherein the first traction member 12 is wound up faster due to the smaller radius R1 of its roller 8 than the second traction member 13 is wound off its roller 9. The two roller units 6 are thus moved upwards in the machine frame guide 10, i.e., in reverse direction to the lowered marking laser 2 and at twice the speed of that of the lowered marking laser 2.

(10) If the marking laser 2 is lifted by means of its drive motor, the protection door 3 remains fixed at its height by the self-inhibition of its non-driven motor. By lifting the marking laser 2, the first traction member 12 is wound off its roller 8 and the second traction member 13 is wound onto its roller 9, wherein the first traction member 12 is wound off faster due to the smaller radius R1 of its roller 8 than the second traction member 13 is wound onto its roller 9. The two roller units 6 are thus moved downwards in the machine frame guide 10, i.e., in a reverse direction to the lifted marking laser 2 and at twice the speed of that of the lifted marking laser 2.

(11) As only an upward or downward displacement force is applied to the axle 7 when lowering or lifting the marking laser 2, the moving marking laser 2 remains weight compensated by means of the protection door 3 and the counterweight mG.

(12) If the protection door 3 is displaced in height, for example lowered by its drive motor, the marking laser 2 remains fixed at its height by the self-retention of its non-driven motor. By lowering the protection door 3, the second traction member 13 is wound off its roller 9 and the first traction member 12 onto its roller 8, wherein the second traction member 13 is wound off more slowly due to the greater radius R2 of its roller 9 than the first traction member 12 is wound onto its roller 8. The two roller units 6 therefore move upward in the machine frame guide 10, i.e., in reverse direction to the lowered protection door 3 and at twice the speed of the lowered protection door 3.

(13) If the protection door 3 is lifted by means of its drive motor, the marking laser 2 remains fixed at its height by the self-retention of its non-driven motor. By lifting the protection door 3, the second traction member 13 is wound onto its roller 9 and the first traction member 12 off its roller 8, wherein the second traction member 13 is wound on more slowly the due to the greater radius R2 of its roller 9 than the first traction member 12 is wound off its roller 8. The two roller units 6 therefore move downward in the machine frame guide 10, i.e., in reverse direction to the lifted protection door 3 and more slowly than the lifted protection door 3, wherein the potential energy of the system consisting of the protection door 3 and the counterweight device 5 always remains the same.

(14) As only an upward or downward displacement force is applied to the axle 7 when lowering or lifting the protection door 3, the moving protection door 3 remains weight compensated by means of the marking laser 2 and the counterweight mG.

(15) Unlike in the system shown in FIG. 2, only the machine frame guide 10 is aligned horizontally in the laser processing machine 1 of FIG. 3 and the counterweight device 5 is formed by a spring balancer, which engages the axle 7 with counterforce FG. The spring balancer can, for example, be designed as a tension spring or a gas spring, as indicated in FIG. 3, or as a spring rope pulley pre-tensioned against unwinding. As shown by means of the broken line, the counterweight device 5 can also be a counterweight mG, suspended from the axle 7 by means of a traction member 15 and diverted via a deflection pulley 14.

(16) The machine frame guide 10 can also be aligned obliquely instead of vertically, as shown in FIGS. 1 and 2, or horizontally as shown in FIG. 3.

(17) Unlike the embodiments of FIGS. 1 to 3, where the entire marking laser 2 can be height adjusted with the laser resonator 2a and the laser processing optical system 2b, in some embodiments, only the laser processing optical system 2b can be height adjustable, for example, while the laser resonator 2a is positioned stationary inside or outside of the laser processing machine. In some embodiments, only the laser processing optical system with the diversion unit are height adjustable. In such embodiments, a fiber laser, and the laser light from the stationary laser resonator can be guided to the laser processing optical system by means of a laser light cable.

Other Embodiments

(18) A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.