The invention relates to a grinding machine for grinding peripheries, clearance angles and protective chamfers in workpieces, preferably workpieces made of steel, hard metal, ceramics, cermet, CBN and PCD, wherein the material processing occurs by means of a grinding wheel preferably formed approximately bowl-shaped, and wherein during the machining the workpiece is held in a workpiece spindle, which is advantageously designed as a ram clamping device, wherein the grinding machine comprises at least four axes, of which at least two axes are designed as rotary axes and at least two axes as linear axes. In this case, the axes are usually in each case at least approximately arranged orthogonally to at least one other axis. From practice, such grinding machines are known in many different embodiments, which are used for the grinding processing of corresponding workpieces.

The disadvantage of this is that only one workpiece can be machined simultaneously, which limits the efficiency of the grinding machine. In addition, the efficiency is also limited by the auxiliary process times due to the removal of a first workpiece after completed machining and by the attachment of a workpiece subsequently to be machined.

The object of the invention is to avoid the aforementioned disadvantages and to provide a grinding machine that allows an improved use of the grinding wheel.

This object is achieved with a grinding machine according to the invention in that a further independently movable workpiece spindle is provided for the synchronous or asynchronous machining of at least two workpieces by the grinding wheel, whereby the workpiece spindles with respect to the grinding spindle are provided in different relative positions such that the workpieces of the two workpiece spindles can be machined simultaneously without collisions by the grinding wheel. As a result, a plurality of workpieces can be machined simultaneously with a single grinding wheel on the different workpiece spindles. The workpieces can be different or the same, and the machining operations can be different or the same. Thus, only one grinding wheel and grinding spindle is required, and consequently only one dressing unit and a corresponding control unit, as well as one handling or robot system, if necessary, is required. This results in significantly improved productivity with only minor additional costs.

According to the invention, the grinding spindle can be arranged in a stationary manner and advantageously mounted rigidly, and the necessary relative movements between the grinding wheel and the respective workpiece are realized by a displacement of the corresponding workpiece spindle.

Preferably, the grinding wheel can be designed as a face grinding wheel or a peripheral grinding wheel or a combination thereof, so that various grinding tasks can be handled without problems.

Advantageously, at least two workpiece spindles can be provided, each of which is provided on a separate rotary table, wherein each of these rotary tables is arranged in each case on a separate displacement device, which is advantageously designed as a linear slide. In this case, a plurality of linear slides can be arranged on a common linear guide. In the present case, the rotary table is understood as a rotary displacement device whose axis of rotation is oriented orthogonally to the axis of rotation of the grinding wheel and orthogonally to the displacement device of the respective guide slide. Thus, at least one rotary table and/or at least one linear slide can be preferably CNC-controlled, with a common control or else a separate control being provided. A rotary table can, for example, be controllable in a range of approximately -100° to approximately +45°, and another rotary table can be controllable, for example, in a range of approximately -45° to approximately +100°.

Preferably at least two displacement devices can be designed as linear slides, which in each case are arranged on separate linear guides or on a common linear guide. Preferably, the linear slides can in each case be arranged on a linear guide which are in each case provided on a displacement device which are likewise designed as (additional) linear slides and which are in each case arranged on separate (additional) linear guides or on a common (additional) linear guide. In a preferred embodiment according to the invention, two workpiece spindles can be provided oriented in opposite directions, wherein the two workpiece spindles are completely or at least substantially designed mirror-inverted and each is arranged facing away from each other with their larger projection in outward direction. Thus, looking at the grinding wheel from the front, a first workpiece spindle can thus, for example, be provided in the "3 o'clock" position, whereby its larger drive side is provided pointing towards the right. A second workpiece spindle, on the other hand, can be provided at the "9 o'clock" position, wherein its larger drive side is provided pointing to the left. Thus simultaneous grinding at the "3 o'clock" and "9 o'clock" positions is possible without collisions. If more than two workpiece spindles are provided, these can be distributed at will. A third workpiece spindle can, for example, be arranged at the "6 o'clock" position.

According to the invention, at least two workpiece spindles can be designed at least partially, preferably completely identical, and/or at least two workpiece spindles can be at least partially, preferably completely, mirror-inverted. This makes it possible to use standard components, which reduces costs and reduces the storage time for repairs.

Furthermore, two workpiece spindles can each be equipped with different clamping systems that enable various machining operations of also identical workpieces, so that different working steps can be carried out at the same time. Thus, for example, a machining of the edge of a workpiece on the first workpiece spindle and a machining of the chip breaker can take place in a perpendicular clamping on the second workpiece spindle. According to the invention, at least one workpiece spindle can be equipped with a measuring system, and both workpiece spindles can preferably be equipped with separate measuring systems. Thus, independent centering and alignment of the workpieces is possible and independent compensation of thermal deviations and disk abrasion for each workpiece spindle to which a separate measuring system is assigned can be carried out.

Advantageously at least two synchronously or asynchronously controllable systems can be assigned for trueing and/or dressing the grinding wheel so that the corresponding machining of the grinding wheel are possible independently of one another and without corresponding auxiliary process times. Furthermore, at least one handling or robot system can be provided for loading and/or unloading at least one workpiece spindle, preferably for loading and/or unloading at least two or all workpiece spindles, so that loading or unloading can take place from the one spindle, while the other workpiece spindle is used for grinding a workpiece.

Preferably, at least one workpiece spindle can be dismantled and exchanged against another device for deviating mechanical machining methods. Advantageously at least one workpiece spindle cannot be dismantled and thus cannot be exchanged with another device for deviating mechanical machining methods.

With at least one workpiece spindle, a third CNC-controlled axis of rotation can also be mounted between the workpiece spindle and the rotary table, which can preferably be oriented orthogonally to the axis of rotation of the rotary table and to the axis of rotation of the workpiece spindle.

Preferably, the workpiece spindles can be moved with their corresponding axes in dependence on one another. Thus, for example, only one workpiece spindle can be equipped with a measuring system and can serve as a "master" for another workpiece spindle designed as "slave."

In the following, an embodiment of the invention shown in the drawing is explained. The sole figure shows a grinding machine 1 for grinding workpieces 2, wherein the material processing takes place by means of an approximately circular bowl-shaped grinding wheel 3.

For the synchronous or asynchronous machining of at least two workpieces 2 by the grinding wheel 3, two workpiece spindles 4 are provided which can be moved independently of one another. The workpiece spindles 4 are provided in different relative positions with respect to the grinding wheel 3 (and the grinding spindle not shown in the figure) in such a way that the workpieces 2 of the two workpiece spindles 4 can be machined simultaneously by the grinding wheel 3 without collisions.

The grinding wheel 3 (and the grinding spindle, not shown in the figure) is arranged stationary and rigidly mounted. The relative movements between the grinding wheel 3 and the respective workpiece 2 required for machining the workpiece 2 are realized by a displacement of the corresponding workpiece spindle 4.

The two workpiece spindles 4 are each provided on a separate rotary table 5, whereby each of these rotary tables 5 are arranged in each case on a separate displacement device designed as a linear slide 6.

For their part, the two linear slides 6 are each arranged on a linear guide 8, which is provided in each case on a displacement device, also designed as a linear slide 7. The orientation of the linear guides 8 and thus the direction of displacement of the linear slides 6 is in each case aligned parallel to the axis of rotation of the grinding wheel 3.

The two linear slides 7 are in turn arranged on a common linear guide 9. The orientation of the linear guide 9 and thus of the displacement direction of the linear slides 7 is oriented orthogonally to the orientation of the displacement direction of the linear slides 6.

The respective axis of rotation of the rotary tables 5 is in each case aligned orthogonally to the axis of rotation of the grinding wheel 3 and orthogonally to the direction of displacement of the respective linear slide 6 as well as orthogonal to the direction of displacement of the respective linear slide 7. The rotary table 5 shown in the figure on the left can be controlled, for example, in a range of approximately -100° to approximately +45°, and the rotary table 5 shown in the figure on the right can be controlled, for example, in a range of approximately -45° to approximately +100°. The two workpiece spindles 4 are provided to be oriented in opposite directions and are designed differently. The right-hand workpiece spindle 4 is arranged with its larger projection facing outwards, i.e. facing to the right.

Thus, this workpiece spindle 4 has a third CNC-controlled axis of rotation 10, which is mounted between the workpiece spindle 4 and the rotary table 5. The axis of rotation 10 is thereby oriented both orthogonally to the axis of rotation of the rotary table 5 and also orthogonally to the axis of rotation of the workpiece spindle 4.