GB2426945A

GB2426945A - Working opposed members of a workpiece

Info

Publication number: GB2426945A
Application number: GB0524822A
Authority: GB
Inventors: Wolfgang Rupp; Daniel Kucher; Bernhard Stahli; Peter Niklaus
Original assignee: STAEHLI LAEPP TECHNIK AG; Carl Zeiss SMT GmbH
Current assignee: STAEHLI LAEPP TECHNIK AG; Carl Zeiss SMT GmbH
Priority date: 2004-12-17
Filing date: 2005-12-06
Publication date: 2006-12-13
Also published as: GB0524822D0

Abstract

A method of polishing, honing, lapping or grinding opposite faces of a workpiece 2 which lies between two tools 3.1 & 4.1. Both tools have central areas and at least one is displaced so that the corresponding central area is displaced across the adjacent face of the workpiece during working. This tool may be displaced linearly, sinusoidally or epicyclically. Suitable apparatus comprises two opposed rotatable tools 3.1 & 4.1, the first 3.1 being displaceable in perpendicular directions by means of two drives 5.3 & 5.4, and the second 4.1 also being displaceable in perpendicular directions by means of drives 5.6 & 5.7. Alternatively one of the tools may be mounted to a frame which may be rotated, as shown in figures 5 & 6. The method may be used to polish LCD masks.

Description

DEVICE AND METHOD FOR SURFACE WORKING

BACKGROUND OF THE INVENTION

The invention relates to a device for the surface working of a body, in particular an LCD mask. The invention further relates to a corresponding method for the surface working of a body.

Surfaces with a particularly high surface quality, especially a low surface roughness, are required for numerous applications in the optical industry but also in other branches of in- dustry. Two high-quality surfaces parallel to one another are required, in particular, for comparatively thin LCD masks, such as those used for flat screens. In order to achieve a high surface quality, a plurality of different methods are known for fine surface working, for example, grinding, in particular precision grinding, lapping, honing, polishing etc. With all these methods, in order to achieve a high surface quality, it is necessary to achieve a re- moval of material which is as uniform as possible over the entire surface of the body.

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Two different working methods are usually used for the fine working of plane surfaces of bodies. With the so-called single-disk method, the body to be worked is affixed to a sup- port. The body is then guided by corresponding support kinematics in circular, oscillating movements over a rotating disk-shaped tool. Thus, an epicycloidal relative movement be- * tween the body and the tool is achieved. The epicycloids formed can be guided over the * body in a surface-covering fashion by suitably controlling the speeds of the guide and tool movements and the excursions of the guide movement such that a homogeneous removal of material is achieved.

A disadvantage with these single-disk methods is that working of the body is in each case only possible from one side such that strong requirements with respect to parallelism of two surfaces can only be satisfied at very high expenditure. In addition, the body must be af- fixed to the support in an expensive fashion to be as free from stresses as possible. In addition, not least for this reason, only a comparatively low removal performance can be achieved.

Higher removal performances can be achieved using so-called two-disk methods in which the body is guided between two rotating parallel diskshaped tools. In order to counteract any inhomogeneous removal of material due to the decrease of the circumferential speed towards the center of the rotating disk, in a corresponding generic device, the body to be worked is guided by a planet wheel of a planetary-gearing-like guide device. In this case, predetermined by the geometry of the guide device, a plane guide movement of the body in two directions running transverse to one another is obtained. As a result of the superposi- tion with a rotary movement of the respective tool, an epicycloidal relative movement be- tween body and tool is also obtained here. The epicycloids formed in this case can be io guided over the body in a surface-covering fashion by suitably controlling the speeds of the guide and tool movements such that a homogeneous removal of material is achieved.

Thanks to the arrangement of the body to be worked between the two tool disks, higher contact pressures and, therefore, a higher removal performance can be achieved com- pared to the single-disk method, but comparatively narrow limits are imposed on the trans- verse dimensions of the body for a predetermined size of working device. This is because, as a result of the planetary-gearing-like guide device, at any time only one ring-segment- shaped area of the tool disks can be used. The ratio of the diameter of a tool disk to the * maximum transverse dimension of a body to be worked is usually at about 3.5 to 4. In order * :: : to work bodies having larger transverse dimensions, considerably larger devices are therefore required. With such large devices however, considerable problems arise with re- gard to maintaining the working precision which can only be overcome, if at all, at very: I...

great expense. **** * * S.. S..' * S S S. S

SUMMARY OF THE INVENTION

It is thus an object of the invention to provide a device and a method for surface working which does not or at least to a lesser extent have the aforesaid disadvantages and espe- cially makes it possible to work large surfaces economically.

The invention is based on the cognition that an improved usage of the available working surface of the tool is achieved if at least one of the first central area of the first working surface of the first tool and the second central area of the second working surface of the second tool is displaced over at least a part of the associated one of the first surface and the second surface to be worked.

Unlike in the known devices in which the centrally arranged sun wheel of the planetary- gearing-like guide device prevents the surface of the body to be worked from being guided over this central area, it is hereby possible to use at least a majority of the available working surface at the same time. As a result, bodies having larger dimensions can be worked with- out the need to change the tool dimensions.

One object of the invention is thus a method for surface working of a body having a first surface to be worked and a second surface to be worked. The method comprises, in a first step, providing a first tool and a second tool, in a second step, placing the body between the first tool and the second tool, and, in a third step, working the first surface and the second surface. The first surface is worked by a first working surface of the first tool, the first working surface having a first central area, while the second surface is worked by a second working surface of the second tool, the second working surface having a second central area. In the third step, the second tool lies opposite to the first tool to form a working gap, the working gap mainly extending in a working gap plane. Furthermore, in the third step, at least one of the first tool and the second tool is displaced in at least one of a first tool dis- placement movement and a second tool displacement movement such that at least one of the first central area and the second central area is displaced over at least a part of the a...

associated one of the first surface and the second surface. * :: : A further object of the invention is a method for surface working of a body having a first surface to be worked and a second surface to be worked. The method comprises, in a first a...

step, providing a first tool and a second tool, in a second step, placing the body between the first tool and the second tool, and, in a third step, working the first surface and the sec- ond surface. The first surface is worked by a first working surface of the first tool, the first working surface having a first central area, while the second surface being worked by a second working surface of the second tool, the second working surface having a second central area. In the third step, the second tool lies opposite to the first tool to form a working gap, the working gap mainly extending in a working gap plane. In the third step, the first tool is displaced in at least one tool displacement movement such that the first central area is displaced over at least a part of the first surface, and, in the third step as well, the second tool is displaced in at least one tool displacement movement such that the second central area is displaced over at least a part of the second surface.

A further object of the invention is a device for surface working of a body having a first sur- face to be worked and a second surface to be worked. The device comprises a first tool, a second tool and at least one drive device. The first tool has a first working surface for working the first surface, the first working surface having a first central area, while the sec- ond tool has a second working surface for working the second surface, the second working surface having a second central area. The second tool is located opposite to the first tool when working the body to form a working gap, the working gap mainly extending in a working gap plane. Furthermore, the at least one drive device is adapted to displace at least one of the first tool and the second tool in at least one of a first tool displacement movement and a second tool displacement movement such that at least one of the first central area and the second central area is displaced over at least a part of the associated rn one of the first surface and the second surface.

A further object of the invention is a device for surface working of a body having a first sur- face to be worked and a second surface to be worked. The device comprises a first tool, a second tool and at least one drive device. The first tool has a first working surface for working the first surface, the first working surface having a first central area, while the sec- ond tool has a second working surface for working the second surface, the second working surface having a second central area. The second tool being located opposite to the first tool when working the body to form a working gap, the working gap mainly extending in a. . working gap plane. The at least one drive device is adapted to displace the first tool in at * :: : least one tool displacement movement such that the first central area is displaced over at least a part of the first surface. Furthermore, the at least one drive device is adapted to displace the second tool in at least one tool displacement movement such that the second central area is displaced over at least a part of the second surface. * S *5SS

Further aspects and embodiments of the invention will become apparent from the depend- * ent claims and the following description of preferred embodiments which refers to the ap- pended figures. All combinations of the features disclosed, whether explicitly recited in the claims or not, are within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of a preferred embodiment of the device for surface working according to the invention for executing a preferred embodiment of the method for surface working according to the invention; Figure 2 is a schematic sectional view of a part of the device from Figure 1 along the line Il-Il in Figure 1; Figure 3 is a schematic block diagram of the control device of the device from Figure 1; Figure 4 is a block diagram of a preferred embodiment of a method for surface working executed with the device for surface working of Figure 1; Figure 5 is a schematic partial view of a further preferred embodiment of the device for surface working according to the invention; Figure 6 is a schematic partial view of a further preferred embodiment of the device for surface working according to the invention; to Figure 7 is a schematic partial view of a further preferred embodiment of the device for surface working according to the invention. * S S...

DETAILED DESCRIPTION OF THE INVENTION S.:

First embodiment *..

In the following, a preferred embodiment of a device 1 for surface working according to the invention, with which a preferred embodiment of the method according to the invention may ** be executed, is described with reference to Figures ito 3. .. : Figure 1 shows a schematic perspective view of the device 1 with which the surfaces of a body 2 can be worked by means of a first tool 3.1 of a first tool device 3 and a second tool 4.1 of a second tool device 4.

In the present case, the body 2 is an LCD mask for a flat screen. However, it is to be un- derstood that, with the device 1, any other bodies for which a corresponding surface quality is required may also undergo corresponding surface working.

The first tool device 3 is arranged on a displaceable first traverse 5.1 of a machine frame 5.

In Figure 1, the first traverse 5.1 is shown in a displacement position at a distance from the body 2 in which the body 2 can be inserted into the device 1. For working the body 2 the traverse 5.1 is displaced by a traverse drive 5.3 -along a first direction 6.1 into an operating position which is indicated in Figure 1 by the dashed contour 5.2. In such an operating po- sition of the first traverse 5.1, the toot 3.1 is located above the body 2.

When the first traverse 5.1 is located in such an operating position 5.2, the tool 3.1, for working the body 2, is displaced by a first tool drive device 3.2 along the first tool axis 3.3 in the direction of the body 2 until the first tool 3.1, in an operating position, abuts against the body 2 with a predetermined pressure.

The first tool 3.1 is a circular-disk-shaped tool with a first disk carrier 3.4 which is connected io via a shaft to the tool drive device 3. 2, and a first working disk 3.5 which is exchangeably affixed to the first disk carrier 3.4. Depending on the application, the first working disk may be a grinding disk, a tapping disk, a honing disk, a polishing disk or a disk for any other type of surface working.

The second tool device 4 is arranged below the receptacle for the body 2. For working the body 2, the second tool 4.1 is displaced by the second tool drive device 4.2 along the sec- em's ond toot axis 4.3 in the direction of the body 2 until the second tool 4. 1 is located in an operating position. Such an operating position of the second tool 4.1 is defined by a pre- definable position along the second tool axis 4.3. When the second tool 4. 1 is located in such an operating position, the body 2 is inserted into the device 1, wherein it then rests on the second tool 4.1. At the time of insertion of the body 2, the first tool 3.1 is still located in a...

its displacement position shown in Figure 1, i.e. at a distance from the body 2. The contact pressure between the second tool 4.1 and the body 2 is then mainly produced by means of *: the first toot device 3 which has been driven to an operating position, such that it abuts against the body 2 with a pre-defined pressure. This pressure can be varied during working the body 2 by the first toot drive device 3.2 if the application requires this.

It is to be understood here that, with other variants of the invention, it may also be provided that the contact pressure between the tools and the body may be adjusted via the second tool device, It may likewise be provided that this pressure is detected and controlled by means of both tool devices.

The second tool 4.1 also comprises a circular-disk-shaped tool with a second disk carrier 4.4 which is connected to the toot drive device 4.2 via a shaft, and a second working disk 4.5 which is exchangeably affixed to the second disk carrier 4.4. Depending on the applica- tion, the second working disk may be a grinding disk, a lapping disk, a honing disk, a pol- ishing disk or a disk for any other type of surface working.

As can be seen from Figure 2, for working the body 2, the first tool 3.1 lies opposite to the second tool 4.1. Thus, a working gap 1.1 is formed between them, in which the body 2 is arranged. The working gap 1.1 mainly extends in a working gap plane 1.2 which runs per- pendicular to the tool axes 3.3 and 4.3.

In the operating position of the first tool 3.1, said tool abuts with its substantially plane first working surface 3.6 against the substantially plane first surface 2.1 of the body 2, said first surface 2.1 being one of the surfaces to be worked. In the operating position of the second tool 4.1, said tool abuts with its substantially plane second working surface 4.6 against the substantially plane second surface 2.2 of the body 2, said second surface 2.2 being the second one of the surfaces to be worked. Here, the second surface 2.2 is substantially par- allel to the first surface 2.1 of the body 2. The working surfaces 3.6 and 4.6 then run paral- lel to the working gap plane 1.2.

The body 2 arranged in the working gap 1.1 between the two tools 3.1 and 4.1 located in an operating position is held in the working gap 1.1 by a holder 7.

The holder 7 comprises a first frame 7.1 supported in the machine frame 5 which is linearly displaceable along a first direction 7.3 by means of a first drive device 7.2. Supported in the *.a.

first frame 7.1 is a cage 7.2 which has a receptacle in the form of a receiving opening 7.3 S...

for receiving the body 2. The cage 7.2 is freely rotatable about an axis running perpendicu- lar to the plane of the first frame 7.1. It is hereby achieved that, in cases of increased con- tact force with the tool which may occur locally as a result of local inhomogeneities, the body 2 can yield so that, during working, forces as uniform as possible act on the body 2.

However, it is to be understood that, for certain applications, especially in order to achieve a higher removal of material, it may be provided to fix the cage 7.2 with respect to the first frame 7.1. For this purpose, corresponding fixing means - not shown - are provided.

For working the first surface 2.1 of the body 2, the first tool drive 3.2 rotates the first tool 3.1 located in an operating position about its tool axis 3.3. Furthermore, the first tool 3.1 is dis- placed by a first drive unit formed by the traverse drive 5.3 in a first tool displacement movement along a first displacement direction parallel to the first direction 6.1. In a second tool displacement movement, the first tool 3.1 is also displaced in a second tool displace- ment movement along a second displacement direction parallel to a second direction 6.2.

The second tool displacement movement is provided by a second drive unit 5.4 displacing the tool 3.1 and the tool drive device 3.2 along the traverse 5.1.

The second direction 6.2 runs transverse, namely perpendicular to the first direction 6.1.

Furthermore, the first direction 6.1 and the second direction 6.2 are parallel to the working gap plane 1.2. Thus, for working the body 2, the first tool 3.1 is displaced in a plane parallel to the working gap plane 1.2.

The first drive unit 5.3 and the second drive unit 5.4 are independent of one another so that the two tool displacement movements may be selected independently of one another.

It is to be understood here that, with other variants of the invention, a single drive device may also be provided which produces, both, the first tool displacement movement and the second tool displacement movement by means of a suitable gearing which, if necessary, has a variable gear ratio. Furthermore, it is understood that, if necessary, the production of only a single tool displacement movement may also be provided.

For working the second surface 2.2 of the body 2, the second tool drive device 4.2 rotates.

the second tool 4.1 located in an operating position about its tool axis 4.3. Furthermore, the:1::, second tool 4.1 is displaced in a third tool displacement movement along a third displace- ment direction parallel to the first direction 6.1. In a fourth tool displacement movement, the second tool 4.1 is also displaced in a fourth tool displacement movement along a fourth *s4* displacement direction parallel to the second direction 6.2. S... *

To provide the third and fourth tool displacement movement, the second tool device 4, similar to the first tool device 3, is mounted to a second traverse 5.5 displaceably supported in the machine frame 5. The third tool displacement movement is provided by a third drive unit 5.6 displacing the second traverse 5.5 and, thus, the second tool 4.1 along the third displacement direction parallel to the first direction 6.1. The fourth tool displacement movement is provided by a fourth drive unit 5.7 displacing the second tool 4.1 and the sec- ond tool drive device 4.2 along the second traverse 5.5 along the fourth displacement di- rection parallel to the second direction 6.2.

Here again the third and fourth displacement direction run transverse, namely perpendicu- lar, to each other. Furthermore, the third and fourth displacement direction are parallel to the working gap plane 1.2. Thus, for working the body 2, the second tool 4.1 is displaced in a plane parallel to the working gap plane 1.2.

The third drive unit 5.6 and the fourth drive unit 5.7 are independent of one another so that the third and fourth tool displacement movements may be selected independently of one another.

It is to be understood here that, with other variants of the invention, a single drive device may also be provided which produces, both, the third and fourth tool displacement move- ment and the second tool displacement movement by means of a suitable gearing which, if necessary, has a variable gear ratio. Furthermore, it is understood that, if necessary, the production of only a single tool displacement movement may also be provided.

The first tool 3.1 may be displaced by the first drive unit 5.3 and the second drive unit 5.4 rn such that the center of area 3.7 of the first working surface 3.6 of the first tool 3.1 is dis- placed over a part of the first surface 2.1 to be worked. In this case, the center of area lies at the central point of the circular working surface 3.6. Thus, the first central region 3.8 of the first working surface 3.6 is also displaced over a part of the first surface 2.1 to be worked. At the same time, the second tool 4.1 may be displaced such that the center of area 4.7 of the second working surface 4.6 of the second tool 4.1 is displaced over a part of the second surface 2.2 to be worked. The center of area 4.7 lies at the central point of the circular working surface 4.6. Thus, the second central region 4.8 of the second working surface 4.6 is displaced over a part of the second surface 2.2 to be worked.

In the representation of Figure 2, the first tool axis 3.3 is in direct alignment with the second tool axis 4.3. This alignment may be maintained over at least a part of the working time of the body 2 by synchronously displacing the first tool 3.1 and the second tool 4.1. . * "I For certain applications, however, it may be favorable or necessary that the two tool axes 3.3 and 4.3 are offset transverse to one another. In order to achieve this, the first tool de- vice 3 may be displaced along the first direction 6.1 and/or the second direction 6.2 by means of the first drive unit 5.3 and the second drive unit 5.4, respectively. Additionally or alternatively, the second tool device 4 may be displaced along the first direction 6.1 and/or the second direction 6.2 by means of the third drive unit 5.6 and the fourth drive unit 5.7, respectively. Here again, this transverse offset between the two tool axes 3.3 and 4.3 may be maintained over at least a part of the working time of the body 2 by synchronously dis- placing the first tool 3.1 and the second tool 4.1.

Anyway, it will be appreciated that, with other embodiments of the invention, a varying transverse offset between the two tool axes 3.3 and 4.3 may be provided over at least a part of the working time of the body 2 by asynchronously displacing the first tool 3.1 and the second tool 4.1.

It is to be understood that, with other variants of the invention, other devices for providing the tool displacement movements may be used. In particular, one or more devices exe- cuted in the fashion of a cross slide used. Furthermore, several devices executed in the fashion of a cross slide may be combined in order to be able to superpose a plurality of linear tool displacement movements which are offset with respect to one another by pre- determined angles and parallel to the working gap plane. Thus, for example, three linear guide movements offset with respect to one another by 1200 may be realized in parallel to the working gap plane.

Herewith, it is possible to use a comparatively large area of the respective working surface of the respective tool 3.1 and 4.1 at the same time. Among other things, on this occasion, the central area around the center of area of the working surface of the respective tool 3.1 and 4.1 may also be used so that, compared with the known devices or methods, signifi- cantly larger bodies may be worked with the same tool size. With the invention it is thus possible to work bodies the maximum transverse dimension of which parallel to the working gap plane 1.2 is only slightly less than the transverse dimension of the respective tool 3.1 * : : and 4. 1 parallel to this plane 1.2.

With the equipment currently available on the market having a tool diameter of about 2 m, it I..

is hereby possible to work bodies 2 having a maximum transverse dimension of up to ap- proximately 2 m. Despite the large transverse dimensions of the body, in this case it is pos- l***' sible to achieve deviations from the desired surface of the body which lie in the range be- tween 10 pm and 100 pm, especially in the range between 10 pm and 50 pm.

As already mentioned, during working the body 2, the first tool 3.1 is set in a rotary move- ment about the first tool axis 3.3 by means of the first tool drive device 3.2 so that this re- sults in a rotary first working surface movement about the first tool axis 3.3. The instanta- neous axis of the first working surface movement in this case passes through the center of area 3.7. Likewise, the second tool 4.1 is set in a rotary movement about the second tool axis 4.3 by means of the second tool drive device 4.2 so that this results in a rotary second working surface movement about the second tool axis 4.3. The instantaneous axis of the second working surface movement in this case passes through the center of area 4.7. -11 -

It is to be understood on this occasion that, with other variants of the invention, if neces- sary, only one single tool drive device may be provided which produces both working sur- face movements by means of a corresponding gearing. In particular, the gear ratio of such a gearing may be variable during operation, if necessary. Likewise, it may also be provided that only one of the tools is driven to produce the corresponding working surface move- ment.

As may be seen from Figure 3, a central control device 8 is connected to the first drive unit 5.3, the second drive unit 5.4, the third drive unit 5.6, the fourth drive unit 5.7, the first tool drive device 3.2 and the second tool drive device 4.2which may all be controlled independ- ently of one another by said control device 8. The first drive unit 5.3, the second drive unit 5.4 and the first tool drive device 3.2 are thereby part of a first drive device 3.9 providing the working movements of the first tool device 3. The third drive unit 5.6, the fourth drive unit 5.7 and the second tool drive device 4.2 are thereby part of a second drive device 4.9 pro- viding the working movements of the first tool device 4.

The control device 8 controls the drives 5.3, 5.4, 5.6, 5.7, 3.2 and 4.2 connected thereto *.ss such that, as a result of the superposition of the tool displacement movements and the * * : working surface movements, over the entire first surface 2.1 to be worked and the entire second surface 2.2 to be worked, a uniform removal of material and, thus, a uniform sur*.** face quality are obtained. By the term uniform surface quality should be understood, in the * ..

sense of the present application, that the surface roughness over the surface to be worked varies by less than 30% of an average value of the surface roughness. ::::: The control is executed such that the amount of the relative speed between the respective surface to be worked and the associated working surface is subject to as little variation as possible at every point. Particularly favourable force ratios are hereby achieved during the working which result in a high surface quality. In particular, the control is executed such that the amount of this relative speed is never zero at any point in time. The movements can be superposed for this purpose such that, overall, a sinusoidal guide movement is obtained.

Furthermore, the rotary working surface movements may be selected to be in the same or in opposite directions.

The control device 8 and the drives 5.3, 5.4, 5.6, 5.7, 3.2 and 4.2 connected thereto are constructed such that the speed and the excursion and, thus, the movement profile of the respective movement produced bythem may be freely, in particular continuously, varied or - 12 - set. It is to be understood however that, with other variants of the invention, this may not be provided at all or only for some of these drives.

In particular, the control device 8 may control the drives 5.3, 5.4, 5.6, 5.7, 3.2 and 4.2 such that, as a result of the superposition of the tool displacement movements and the tool movements, an epicycloidal relative movement is obtained between the body 2 and the respective working surface 3.6 and 4.6. The resulting epicycloid tracks of a tool surface point on the body 2 may then be guided in a surface-covering fashion to achieve uniform removal of material over the entire surface of the body 2 to be worked.

In the following, a preferred embodiment of the method according to the invention executed io with the device 1 for surface working will be described with reference to Figures 1 to 4.

In a first step 9.1, the first tool 3.1 and the second tool 4.1 are provided as a part of the device 1 to provide a configuration as it has been described above in the context of Figures 1 to 3. S...

S S * ...

In a second step 9.2, the body 2 is placed between the first tool 3.1 and the second tool * 4.1. To this end, the body 2 is placed into the receptacle 7.3 of the holder 7 after the sec- ond tool 4.1 has been brought in an operating position. At the time of insertion of the body * 2, the first tool 3.1 is still located in its displacement position shown in Figure 1, i.e. at a. . distance from the body 2. The contact pressure between the second tool 4.1 and the body 2 is then mainly produced by means of the first tool device 3 which is driven to an operating position, such that it abuts against the body 2 with a pre-defined pressure. S In a third step 9.3, the first surface 2.1 of the body 2 is then worked with the first tool 3.1 while the second surface 2.2 of the body 2 is worked with the second tool 4.1 as it has been described above in the context of Figures 1 to 3.

Second embodiment In the following, a second preferred embodiment of a device for surface working according to the invention, with which a preferred embodiment of the method according to the inven- tion may be executed, is described with reference to Figures 1 to 5.

Figure 5 shows a schematic representation of a second drive device 104.9 of this preferred embodiment of the device for surface working. This device for surface working, apart from - 13- the second drive device 104.9, does not differ from the one from Figures 1 to 3. Thus, only the differences with regard to the second drive device 104.9 will be discussed here.

The second drive device 104.9 comprises a first frame 105.5 mounted in a machine frame - not shown - which may be displaced linearly in a first direction 106.1 by means of a third drive unit 105.6 connected to the control unit 8 (not shown). Here, the first direction 106.1 runs parallel to the plane of the working gap.

The second drive device 104.9 further comprises a circular second frame 105.8 mounted on the first frame 105.5. The second tool drive device 4.2 with the second tool 4.1 is mounted excentrically to the circular second frame 105.8 io This second frame 105.8 may be rotated in a second direction 106.2 by means of a fourth drive unit 105.7 affixed to the first frame 105.5 and connected to the control unit 8 (not shown). Here, the second direction 106.2 runs parallel to the plane of the working gap and transverse to the first direction 106.1. *.a* * S

A linear third tool displacement movement along the first direction 106.1 may be imposed ** : :.

on the tool 4.1 by means of the third drive unit 105.6. A rotary fourth tool displacement run- fling transverse to the third tool displacement movement along the second direction 106.2 may be imposed on the second tool 4.1 by means of the fourth drive unit 105.7. The third drive unit 105.6 and the fourth drive unit 105.7 are independent of one another such that the two tool displacement movements may be set independently of one another. S... * . S a

With the second drive device 104.9 as well, the second tool 4.1 may be displaced such that the center of area 4.7 of the second working surface 4.6 of the second tool 4.1 is displaced over a part of the body's second surface 2.2 which is to be worked.

It is hereby possible to use a comparatively large area of the respective working surface 4.6 of the second tool 4.1 at the same time. Here, among other things, the central area 4.8 of the second tool 4.1 may be used such that, compared with the known devices or methods, significantly larger bodies may be worked using an unchanged tool size. With the invention, it is thus possible to work bodies whose maximum transverse dimension parallel to the working gap plane 1.2 of the working gap 1 1 is only slightly less than the transverse di- mension of the second tool 4.1 parallel to this plane. - 14-

Using the second drive device 104.9 it is possible, among other things, to control the tool displacement movements and the tool movements by the control unit 8 such that, as a re- suit of their superposition, an epicycloidal relative movement is obtained between the body 2 and the respective tool 3.1 and 4.1. The resulting epicycloid tracks of a tool surface point on the body 2 may then be guided in a surface- covering fashion to achieve substantially uniform removal of material over the entire surface of the body 2 to be worked.

It will be appreciated that this embodiment as well may execute the method of surface working as it has been described above in the context of Figure 4.

Third embodiment io In the following, a third preferred embodiment of a device for surface working according to the invention, with which a preferred embodiment of the method according to the invention may be executed, is described with reference to Figures 1 to 3 and 6.

Figure 6 shows a schematic representation of the second drive device 204. 9 of this pre- : :: ferred embodiment of the device for surface working according to the invention. This device: for surface working, apart from the second drive device 204.9, does not differ from the one from Figure 1. Thus, only the differences with regard to this second drive device 204.9 will be discussed here. I...

The second drive device 204.9 comprises a circular first frame 205.5 mounted in a machine frame - not shown - which may be rotated in a first direction 206.1 by means of a third drive * .. : unit 205.6 connected to the control unit 8 (not shown). Here, the first direction 206.1 runs parallel to the plane of the working gap.

The second drive device 204.9 further comprises a circular second frame 205.8 excentri- cally mounted on the first frame 205.5. The second tool drive device 4.2 with the second tool 4.1, in turn, is mounted excentrically to the circular second frame 205.8 This second frame 205.8 may be rotated in a second direction 206.2 by means of a fourth drive unit 205.7 affixed to the first frame 205.5 and connected to the control unit 8 (not shown). Here, the second direction 206.2 runs parallel to the plane of the working gap and transverse to the first direction 206.1. - 15-

A rotary third tool displacement movement along the first direction 206.1 may be imposed on the tool 4.1 by means of the third drive unit 205.6. A rotary fourth tool displacement run- fling transverse to the third tool displacement movement along the second direction 206.2 may be imposed on the second tool 4.1 by means of the fourth drive unit 205.7. The third drive unit 205.6 and the fourth drive unit 205.7 are independent of one another such that the two tool displacement movements may be set independently of one another.

With the second drive device 204.9 as well, the second tool 4.1 may be displaced such that the center of area 4.7 of the second working surface 4.6 of the second tool 4.1 is displaced over a part of the body's second surface 2.2 which is to be worked.

It is hereby possible to use a comparatively large area of the respective working surface 4.6 of the second tool 4.1 at the same time. Here, among other things, the central area 4.8 of the second tool 4.1 may be used such that, compared with the known devices or methods, significantly larger bodies may be worked using an unchanged tool size. With the invention, it is thus possible to work bodies whose maximum transverse dimension parallel to the

SS

working gap plane 1.2 of the working gap 1.1 is only slightly less than the transverse di- * S...

mension of the second tool 4.1 parallel to this plane. . : Using the second drive device 204.9 it is possible, among other things, to control the tool displacement movements and the tool movements by the control unit 8 such that, as a re- *.:.

suit of their superposition, an epicycloidal relative movement is obtained between the body 2 and the respective tool 3.1 and 4.1. The resulting epicycloid tracks of a tool surface point on the body 2 may then be guided in a surface- covering fashion to achieve substantially uniform removal of material over the entire surface of the body 2 to be worked.

Fourth embodiment In the following, a fourth preferred embodiment of a device for surface working according to the invention, with which a preferred embodiment of the method according to the invention may be executed, is described with reference to Figures 1 to 3 and 7.

Figure 7 shows a schematic representation, not to scale, of the first tool device 303 of this fourth embodiment of the device for surface working according to the invention. This device - 16- for surface working, apart from the first tool device 303, does not from that from Figure 1.

Thus, the differences with respect to the tool device 303 will be discussed here.

One difference from the first tool device 3 from Figure 1 is that the first tool device 303 has a first tool 303.1 with a concave spherical first working surface 303.6. The curvature of the first working surface 303.6 is shown greatly exaggerated in Figure 7 for reasons of better perceptibility. In actual applications, working surfaces with a considerably smaller curvature, i.e. a considerably larger radius of curvature, are used. It is hereby possible to work sur- faces of a body which deviate from a plane geometry.

A further difference from the first tool device 303 from Figure 1 consists in the fact that the first tool device 303 comprises a first tool drive device 303.2 which is additionally con- structed to tilt the first tool axis 303.3 in the plane of the drawing in the direction of the dou- ble arrow 310 about a pivot point lying on the first tool axis 303.3. Furthermore, the first tool drive device 303.2 may additionally be constructed to tilt the tool axis 303.3 in a plane lying transverse to the plane of the drawing about a pivot point lying on the first tool axis 303.3.

As a result, a particularly variable use of the device according to the invention is possible * S..

for almost any surfaces to be worked. * *a: It is to be understood that the first working surface, in other variants of the invention, may also have a different geometry. Thus, for example, it may have a convex spherical geome- try as is indicated by the dashed contour 311 in Figure 7. Furthermore, it may also have a S...

concave or convex conical geometry, as is indicated by the contours 312 and 313 in Figure 7. It is furthermore understood that section-wise combinations of such geometries are also ** possible. Finally, it is to be understood that, in the case of a convex geometry of the work- ing surface, the tilting movements of the tools are adapted hereto. The pivot point of the pivoting movement then generally lies on the other side of the tool compared to the con- cave geometry.

As already mentioned, the curvatures or angles of inclination of the first working surface are shown highly exaggerated in Figure 7 for reasons of better perceptibility. In actual applica- tions working surfaces with a considerably smaller curvature or smaller angles of inclination are used. It is hereby possible also to work surfaces of a body which deviate from a plane geometry.

It is to be understood that, with other variants of the invention, the second tool may also have a second working surface which deviates from a plane geometry. Furthermore, it is - 17- understood that, according to the required application, any combinations of tools with dif- ferent geometries of the working surface are possible.

In general, but especially in connection with the variants having a working surface which deviates from a plane geometry, it is to be understood that the working surface must not necessarily touch or work the part of the surface to be worked over which the central area is displaced when the tool is displaced over this part of the surface to be worked. Rather, the displacement of an area of a surface over an area of another surface in the sense of the present application shall also comprise constellations in which these areas do not touch but are merely guided past one another at a distance. In such cases, it is furthermore to be understood that, in this central area, the working surface must not necessarily be con- structed to work the body in this central area, a working surface must not necessarily be provided. Rather, for example, the central area, especially the center, i.e., the center of area, of an annular working surface lies at the center of this circular ring without a working ".. a.. .

surface actually being provided there. : The invention is described hereinbefore with reference to examples in which, exclusively, rotationally symmetrical surfaces of a body are worked. It is to be understood that, by suita- *.:.

bly specifying the movement profile of the relative movement between the working surfaces * . and the body, non-rotationally symmetrical surfaces of a body, in particular aspherical sur- faces and free-form surfaces, may also be worked using the invention. S. *****

Claims

What is claimed is: 1. A method for surface working of a body having a

first surface to be worked and a second surface to be worked, comprising in a first step, providing a first tool and a second tool, - in a second step, placing said body between said first tool and said second tool, and, - in a third step, working said first surface and said second surface; said first surface being worked by a first working surface of said first tool, said first working surface having a first central area, - said second surface being worked by a second working surface of said second tool, said second working surface having a second central area, S.. .

- in said third step, said second tool lying opposite to said first tool to form a work- * S...

ing gap, said working gap mainly extending in a working gap plane, * - in said third step, at least one of said first tool and said second tool being dis- placed in at least one of a first tool displacement movement and a second tool: displacement movement such that at least one of said first central area and said second central area is displaced over at least a part of the associated one of said first surface and said second surface.
2. The method according to claim 1, wherein, - in said third step, at least one of said first tool and said second tool is displaced in a first tool displacement movement and a second tool displacement movement, - said first tool displacement movement being directed along a first displacement direction and said second tool displacement movement being directed along a second displacement direction running transverse to said first displacement direc- tion.
3. The method according to claim 2, wherein said first displacement direction and said second displacement direction run parallel to said working gap plane.
4. The method according to claim 1, wherein, in said third step, at least one of the cen- ter of area of said first working surface and the center of area of said second working surface is displaced over at least a part of the associated one of said first surface and said second surface.
5. The method according to claim 1, wherein, in said third step, - at least one of said first working surface and said second working surface exe- cutes an at least partly rotary movement, - said first working surface executing an at least partly rotary first working surface movement, - said second working surface executing an at least partly rotary second working surface movement and - at least one of the instantaneous center of motion of said first working surface and the instantaneous center of motion of said second working surface is displaced over at least a part of the associated one of said first surface and said sec- * . S...

ond surface.
6. The method according to claim 1, wherein, in said third step, at least one of a linear tool displacement movement and a sinusoidal tool displacement movement is im- S...

posed on at least one of said first tool and said second tool. I... * S... *.
7. The method according to claim 1, wherein, in said third step, S.. : at least one of a first tool movement is imposed on said first tool and a second tool movement is imposed on said second tool, - at least one of said first tool displacement movement and said second tool dis- placement movement and at least one of said first tool movement and said second tool movement are controlled such that, as a result of their superposition, a rela- tive movement with substantially uniform surface-covering material removal from said body is obtained between said body and at least one of said first tool and said second tool.
8. The method according to claim 7, wherein at least one of said first tool displacement movement and said second tool displacement movement and at least one of said first tool movement and said second tool movement are controlled such that, as a result 2 of their superposition, an epicycloidal relative movement is obtained between said body and at least one of said first tool and said second toot.
9. The method according to claim 1, wherein said first tool displacement movement is independent of said second tool displacement movement.
10. The method according to claim 1, wherein at least one of the speed and the excur- sion of at least one of said first tool displacement movement and said second tool displacement movement is continuously adjustable.
11. The method according to claim 1, wherein the contact pressure between at least one of said first tool and said second tool and said body is adjustable.
12. The method according to claim 1, wherein, in said third step, - at least one of a first tool movement is imposed on said first tool and a second tool movement is imposed on said second tool, S...

S S P

- at least one of said first toot movement and said second tool movement being a rotary movement, S*S* - said first tool movement being a first rotary movement about a first tool axis which *..

is substantially perpendicular to said working gap plane, .55... 5SSS

- said second tool movement being a second rotary movement about a second tool * . . a axis which is substantially perpendicular to said working gap plane. .. :
13. The method according to claim 12, wherein said first tool axis is adjustable trans- verse to said second tool axis.
14. The method according to claim 12, wherein said first tool axis is arranged offset transverse to said second tool axis.
15. The method according to claim 12, wherein said first tool movement is independent of said second tool movement.
16. The method according to claim 12, wherein at least one of the speed and the excur- sion of at least one of said first tool movement and said second toot movement is continuously adjustable.
17. The method according to claim 1, wherein it is used for a type of surface working selected from a group consisting of grinding, lapping, honing, polishing and combina- tions thereof.
18. The method according to claim 1, wherein said body is an LCD mask.
19. A method for surface working of a body having a first surface to be worked and a second surface to be worked, comprising - in a first step, providing a first tool and a second tool, - in a second step, placing said body between said first tool and said second tool, and, S...

- in a third step, working said first surface and said second surface; said first surface being worked by a first working surface of said first tool, said first working surface having a first central area, *5SS - said second surface being worked by a second working surface of said second tool, said second working surface having a second central area, *5S* - in said third step, said second tool lying opposite to said first tool to form a work- ing gap, said working gap mainly extending in a working gap plane, - in said third step, said first tool being displaced in at least one tool displacement movement such that said first central area is displaced over at least a part of said first surface, and * in said third step, said second tool being displaced in at least one tool displace- ment movement such that said second central area is displaced over at least a part of said second surface.
20. The method according to claim 19, wherein, - in said third step, said first tool is displaced in a first tool displacement movement and a second tool displacement movement, - said first tool displacement movement being directed along a first displacement direction and said second tool displacement movement being directed along a second displacement direction running transverse to said first displacement direc- tion.
21. The method according to claim 20, wherein said first displacement direction and said second displacement direction run parallel to said working gap plane.
22. The method according to claim 20, wherein said first tool displacement movement is independent of said second tool displacement movement.
23. The method according to claim 20, wherein at least one of the speed and the excur- sion of at least one of said first tool displacement movement and said second tool displacement movement is continuously adjustable.
24. The method according to claim 19, wherein, s." S...

- in said third step, said second tool is displaced in a third tool displacement * movement and a fourth tool displacement movement, 15. said third tool displacement movement being directed along a third displacement direction and said fourth tool displacement movement being directed along a I''.

fourth displacement direction running transverse to said third displacement direc- tion.

S
25. The method according to claim 24, wherein said third displacement direction and said fourth displacement direction run parallel to said working gap plane.
26. The method according to claim 24, wherein said third tool displacement movement is independent of said fourth tool displacement movement.
27. The method according to claim 24, wherein at least one of the speed and the excur- sion of at least one of said third tool displacement movement and said fourth tool dis- placement movement is continuously adjustable.
28. The method according to claim 19, wherein, in said third step, - the center of area of said first working surface is displaced over at least a part of said first surface, and - the center of area of said second working surface is displaced over at least a part of said second surface.
29. The method according to claim 19, wherein, in said third step, - said first working surface executes an at least partly rotary first working surface movement, and * the instantaneous center of motion of said first working surface is displaced over at least a part of said first surface.
30. The method according to claim 19, wherein, in said third step, - said second working surface executes an at least partly rotary second working surface movement, and - the instantaneous center of motion of said second working surface is displaced S *. S..

over at least a part of said second surface. * :
31. The method according to claim 19, wherein, in said third step, at least one of a linear tool displacement movement and a sinusoidal tool displacement movement is imposed on at least one of said first tool and said second tool. * *S.S *5*S * S S *5 5
32. The method according to claim 19, wherein, in said third step, - a first tool movement is imposed on said first tool, and - said at least one tool displacement movement of said first tool and said first tool movement are controlled such that, as a result of their superposition, a relative movement with substantially uniform surfacecovering material removal from said body is obtained between said body and said first tool.
33. The method according to claim 32, wherein said at least one tool displacement movement of said first tool and said first tool movement are controlled such that, as a result of their superposition, an epicycloidal relative movement is obtained between said body and said first tool.
34. The method according to claim 19, wherein, in said third step, - a second tool movement is imposed on said second tool, and - said at least one tool displacement movement of said second tool and said sec- ond tool movement are controlled such that, as a result of their superposition, a relative movement with substantially uniform surface- covering material removal from said body is obtained between said body and said second tool.
35. The method according to claim 34, wherein said at least one tool displacement movement of said second tool and said second tool movement are controlled such that, as a result of their superposition, an epicycloidal relative movement is obtained between said body and said second tool.
36. The method according to claim 19, wherein the contact pressure between at least one of said first tool and said second tool and said body is adjustable. * see. *5*S

S S S
37. The method according to claim 19, wherein, in said third step, - a first tool movement is imposed on said first tool and a second tool movement is S...

imposed on said second tool, ..:.

- said first tool movement being a first rotary movement about a first tool axis which. S...

is substantially perpendicular to said working gap plane, ::: : - said second tool movement being a second rotary movement about a second tool axis which is substantially perpendicular to said working gap plane.
38. The method according to claim 37, wherein said first tool axis is adjustable trans- verse to said second tool axis.
39. The method according to claim 37, wherein said first tool axis is arranged offset transverse to said second tool axis.
40. The method according to claim 37, wherein said first tool movement is independent of said second tool movement.
41. The method according to claim 37, wherein at least one of the speed and the excur- sion of at least one of said first tool movement and said second tool movement is continuously adjustable.
42. The method according to claim 19, wherein it is used for a type of surface working selected from a group consisting of grinding, lapping, honing, polishing and combina- tions thereof.
43. The method according to claim 19, wherein said body is an LCD mask.
44. A device for surface working of a body having a first surface to be worked and a sec- ond surface to be worked, comprising - afirsttool, * asecondtool,and i.e. I...

- at least one drive device; . : - said first tool having a first working surface for working said first surface, said first working surface having a first central area, : i.e. - said second tool having a second working surface for working said second sur- S...

face, said second working surface having a second central area, S...

- said second tool being located opposite to said first tool when working said body to form a working gap, said working gap mainly extending in a working gap plane, - said at least one drive device being adapted to displace at least one of said first tool and said second tool in at least one of a first tool displacement movement and a second tool displacement movement such that at least one of said first central area and said second central area is displaced over at least a part of the associ- ated one of said first surface and said second surface.

*
45. The device according to claim 44, wherein, - said at least one drive device is adapted to displace at least one of said first tool and said second tool in a first tool displacement movement and a second tool displacement movement, - said first tool displacement movement being directed along a first displacement direction and said second tool displacement movement being directed along a second displacement direction running transverse to said first displacement direc- tion.
46. The device according to claim 45, wherein said first displacement direction and said second displacement direction run parallel to said working gap plane.
47. The device according to claim 44, wherein, said at least one drive device is adapted to displace at least one of the center of area of said first working surface and the center of area of said second working surface over at least a part of the associated one of said first surface and said second surface.
48. The device according to claim 44, wherein, - said at least one drive device is adapted to impose an at least partly rotary movement on at least one of said first working surface and said second working surface, I * said first working surface executing an at least partly rotary first working surface movement, S...

- said second working surface executing an at least partly rotary second working surface movement and * * , * S...

- said at least one drive device is adapted to displace at least one of the instanta- ::: : neous center of motion of said first working surface and the instantaneous center of motion of said second working surface over at least a part of the associated one of said first surface and said second surface.
49. The device according to claim 44, wherein, said at least one drive device is adapted to impose at least one of a linear tool displacement movement and a sinusoidal tool displacement movement on at least one of said first tool and said second tool.
50. The device according to claim 44, wherein, - a control device is provided, said control device being connected to said at least one drive device, - said control device controlling said at least one drive device such that a relative movement with substantially uniform surface-covering material removal from said body is obtained between said body and at least one of said first tool and said second tool.
51. The device according to claim 50, wherein said control device controls said at least one drive device such that an epicycloidal relative movement is obtained between said body and at least one of said first tool and said second tool.
52. The device according to claim 44, wherein said at least one drive device provides a first tool displacement movement being independent of said second tool displace- ment movement.
53. The device according to claim 44, wherein said at least one drive device is adapted io to continuously adjust at least one of the speed and the excursion of at least one of said first tool displacement movement and said second tool displacement movement. * * ****
54. The device according to claim 44, wherein said at least one drive device is adapted * ** : to adjust the contact pressure between at least one of said first tool and said second tool and said body. : S... *
55. The device according to claim 44, wherein..... S...

- said at least one drive device is adapted to impose at least one of a first tool *. : movement on said first tool and a second tool movement is on said second tool, - at least one of said first tool movement and said second tool movement being a rotary movement, - said first tool movement being a first rotary movement about a first tool axis which is substantially perpendicular to said working gap plane, - said second tool movement being a second rotary movement about a second tool axis which is substantially perpendicular to said working gap plane.
56. The device according to claim 55, wherein said at least one drive device is adapted to adjust said first tool axis transverse to said second tool axis.
57. The device according to claim 55, wherein said first tool axis is arranged offset trans- verse to said second tool axis.
58. The device according to claim 55, wherein said at least one drive device provides a first tool movement being independent of said second tool movement.
59. The device according to claim 55, wherein said at least one drive device is adapted to continuously adjust at least one of the speed and the excursion of at least one of said first tool movement and said second tool movement.
60. The device according to claim 44, wherein at least one of said first tool and said sec- ond tool comprises a working surface working said body, said working surface being selected from a group consisting of a grinding surface, a lapping surface, a honing surface and a polishing surface.
61. The device according to claim 44, wherein said body is an LCD mask. *S..
62. A device for surface working of a body having a first surface to be worked and a sec- ond surface to be worked, comprising - a first tool, asecondtool,and - at least one drive device; - said first tool having a first working surface for working said first surface, said first * : working surface having a first central area, - said second tool having a second working surface for working said second sur- face, said second working surface having a second central area, 20. said second tool being located opposite to said first tool when working said body to form a working gap, said working gap mainly extending in a working gap plane, said at least one drive device being adapted to displace said first tool in at least one tool displacement movement such that said first central area is displaced over at least a part of said first surface, and - said at least one drive device being adapted to displace said second tool in at least one tool displacement movement such that said second central area is dis- placed over at least a part of said second surface.
63. The device according to claim 62, wherein, - a first drive device is provided, - said first drive device being adapted to displace said first tool in a first tool dis- placement movement and a second tool displacement movement, - said first tool displacement movement being directed along a first displacement direction and said second tool displacement movement being directed along a second displacement direction running transverse to said first displacement direc- tion.
64. The device according to claim 63, wherein said first displacement direction and said second displacement direction run parallel to said working gap plane.
65. The device according to claim 63, wherein said first drive device is adapted to pro- vide a first tool displacement movement being independent of said second tool dis- placement movement. a.. a... * S S
66. The device according to claim 63, wherein said first drive device is adapted to con- tinuously adjust at least one of the speed and the excursion of at least one of said first tool displacement movement and said second tool displacement movement. : ***. S...
67. The device according to claim 62, wherein, a... * S *

- said first drive device comprises a first drive unit and a second drive unit, - said first drive unit being adapted to displace said first tool in said first tool dis- placement movement and - said second drive unit being adapted to displace said first tool in said second tool displacement movement.
68. The device according to claim 62, wherein, - a second drive device is provided, - said second drive device being adapted to displace said second tool in a third tool displacement movement and a fourth tool displacement movement, - said third tool displacement movement being directed along a third displacement direction and said fourth tool displacement movement being directed along a fourth displacement direction running transverse to said third displacement direc- tion.
69. The device according to claim 68, wherein said third displacement direction and said fourth displacement direction run parallel to said working gap plane.
70. The device according to claim 68, wherein said second drive device is adapted to provide a third tool displacement movement being independent of said fourth tool displacement movement.
71. The device according to claim 68, wherein said first drive device is adapted to con- tinuously adjust at least one of the speed and the excursion of at least one of said third tool displacement movement and said fourth tool displacement movement.
72. The device according to claim 68, wherein, - said second drive device comprises a third drive unit and a fourth drive unit, - said third drive unit being adapted to displace said second tool in said third tool IlIS displacement movement and..:.

- said fourth drive unit being adapted to displace said second tool in said fourth tool * *...

displacement movement.

S
73. The device according to claim 62, wherein - a first drive device and a second drive device is provided, - said first drive device being adapted to displace the center of area of said first working surface is over at least a part of said first surface, and - said second drive device being adapted to displace the center of area of said second working surface over at least a part of said second surface.
74. The device according to claim 62, wherein - a first drive device is provided, - said first drive device being adapted to provide an at least partly rotary first work- ing surface movement of said first working surface, and - said first drive device being adapted to displace the instantaneous center of mo- tion of said first working surface over at least a part of said first surface.
75. The device according to claim 62, wherein - a second drive device is provided, - said second drive device being adapted to provide an at least partly rotary second working surface movement of said second working surface, and - said second drive device being adapted to displace the instantaneous center of motion of said second working surface over at least a part of said second surface.
76. The device according to claim 62, wherein said at least one drive device is adapted io to impose at least one of a linear tool displacement movement and a sinusoidal tool displacement movement on at least one of said first tool and said second tool. * * S...
77. The device according to claim 62, wherein a first drive device is provided, and - a control device is provided; : - said control device being connected to said first drive device, *S.

- said first drive device being adapted to impose a first tool movement on said first tool, and - said control device being adapted to control provision of said at least one tool dis- placement movement of said first tool and said first tool movement by said first drive device such that, as a result of a superposition of said movements, a relative movement with substantially uniform surface- covering material removal from said body is obtained between said body and said first tool.
78. The device according to claim 77, wherein said control device is adapted to control provision of said at least one toot displacement movement of said first tool and said first tool movement by said first drive device such that, as a result of a superposition of said movements, an epicycloidal relative movement is obtained between said body and said first tool.
79. The device according to claim 62, wherein - a second drive device is provided, and - a control device is provided; - said control device being connected to said second drive device, - said second drive device being adapted to impose a second tool movement on said second tool, and - said control device being adapted to control provision of said at least one tool dis- placement movement of said second tool and said second tool movement by said second drive device such that, as a result of a superposition of said movements, a relative movement with substantially uniform surface- covering material removal io from said body is obtained between said body and said second tool.
80. The device according to claim 79, wherein said control device is adapted to control provision of said at least one tool displacement movement of said second tool and said second tool movement by said second drive device such that, as a result of a e.s.

superposition of said movements, an epicycloidal relative movement is obtained be- * tween said body and said second tool. S...
81. The device according to claim 62, wherein said at least one drive device is adapted...

to adjust the contact pressure between at least one of said first tool and said second toolandsaidbody.

S S. S
82. The device according to claim 62, wherein - a first drive device and a second drive device is provided, - said first drive device being adapted to impose a first tool movement on said first tool, - said second drive device being adapted to impose a second tool movement on said second tool, - said first tool movement being a first rotary movement about a first tool axis which is substantially perpendicular to said working gap plane, - said second tool movement being a second rotary movement about a second tool axis which is substantially perpendicular to said working gap plane.
83. The device according to claim 82, wherein at least one of said first drive device and said second drive device is adapted to adjust said first tool axis transverse to said second tool axis.
84. The device according to claim 82, wherein said first tool axis is arranged offset trans- verse to said second tool axis.
85. The device according to claim 82, wherein said first tool movement is independent of said second tool movement.
86. The device according to claim 82, wherein at least one of said first

drive device and said second drive device is adapted to continuously adjust at least one of the speed and the excursion of the associated one of said first tool movement and said second tool movement. * S... S...
87. The device according to claim 62, wherein at least one of said first tool and said sec- * ond tool comprises a working surface working said body, said working surface being selected from a group consisting of a grinding surface, a lapping surface, a honing surface and a polishing surface.

S S *SS
88. The device according to claim 62, wherein said body is an LCD mask. *