MXPA05013353A - Device comprising a floating bearing system and guide track consisting of tiles - Google Patents

Abstract

The invention relates to a device (01) comprising at least two components (09, 10) that can be displaced in relation to one another, at least one floating bearing element (14) being provided on the first component (10). Said element co-operates with a guide track (15) that is configured on the second component (09) in such a way that the first component (10) is guided and/or supported on the second component in a contactless manner by means of an air gap between the floating bearing element (14) and the guide track (15). The latter (15) is composed of tiles (20), which are fixed next to one another on the second component (09).

Description

DEVICE THAT HAS A SUPPORT OF AIR CUSHION AND A GUIDE FORMED OF SOLERAS FIELD OF THE INVENTION The present invention relates to a device having an air cushion support between two components that can be moved towards each other according to the introduction of the claim.

BACKGROUND OF THE INVENTION Generic devices with air cushion supports are used as measuring machines, for example, but not exclusively. The air cushion support allows high precision guidance of the components that can be moved relative to each other. Due to the contactless support, there is no surface friction in the support elements. The air gap between the air cushion support element itself and the opposite positioned guide is usually within the range of 3μm to 10μm. This small gap in the width between the air cushion support element and the guide requires a high production quality, while maintaining very low production tolerances. The requirements of these guides with respect to their flat characteristic and height of crest to valleys in particular, are also extremely high. To allow the manufacture of such high precision guides, it is well known within the art to use materials such as natural hard rock, especially granite. German patent DE 101 40 174 A1, for example, describes a coordinate measuring machine, wherein all components having guides are made of granite. The guides are cut from the natural rock block by means of appropriate machining operations, for example, grinding and polishing. A disadvantage of this type of manufacturing process is that there are some disadvantages to using natural hard rock as the starting material. For example, granite blocks of appropriate size and in appropriate quantities from third world countries can be imported since the materials are not found in Central Europe. The machining of natural hard rock is extremely complex and time consuming. In addition, natural hard rock can only be processed as block material, which greatly limits the design options and in particular, the size of the components to be produced. Therefore, with the background of the technique, the object of the present invention is to propose a novel device having an air cushion support that avoids the disadvantages of the prior art technique. This objective is achieved with a device in accordance with the teaching of claim 1. The favorable modalities are the support of the dependent claims.

BRIEF DESCRIPTION OF THE INVENTION The novel device is based on the fundamental idea that the guides of the air cushion support are no longer made of a solid material such as granite, instead they use sills of an appropriate material which are They couple side by side with a component, which functions as a carrier to form the guide. An advantage of this type of design, in particular, is the fact that the component that offers the support to the guide can be constructed independently of the material of the guide and can therefore be designed as a steel structure. In addition, the dimensions of the guide, especially its maximum length, are no longer limited by the maximum length of the support element, as is the case with the components made of natural hard rock. Instead, the guide can be designed to have the desired length when adding additional sills. As a result, a wide range of design options is generated for the engineer when designing generic devices. Finally, it does not matter which material is selected to manufacture the sole plates that form the guide, it only depends on the corresponding material having the appropriate surface quality. For example, it is possible to achieve that the screeds are made of metals with a hardened or granite surface. Ceramic materials have proven to be especially suitable for producing the solerails that form the guide. In particular, the ceramic material known as Stettalit (ceramic number: C221 according to VDE 0335, Part 3), is an excellent material for forming the guides.

Stettalit is known as the starting material from mass-produced products, such as heat-resistant switches in electric stoves and household accessories and is therefore available at very reasonable prices. Due to material properties (open porosity: 0% vol., Density 2.78 kg / dm3, flexural strength: approximately 140 MPa, hardness 5 in accordance with its Moh scale), high precision guides can be manufactured of this material. The Stettalit can also be machined with the use of normal tools, it is easy to work and therefore its manufacture is not expensive. Essentially, it does not matter the amount of soleras to be added to the corresponding component of the device. For example, mechanical fastening techniques, especially, fastening rails can be used. Since these sills, which are made of ceramics, for example, and the supporting element that is produced as a steel structure, have completely different physical properties, an adhesive joint is particularly suitable for securing the sills with the component. The adhesive must have the lowest possible flow capacity in order to have the ability to join the sills and the support element permanently and safely despite the difference in their expansion coefficients. The two-component construction adhesives have proven to be especially useful for use as adhesives to produce the required adhesive joint. These adhesives are characterized by very low flowability and very high shear strength, impact resistance and peel resistance over a very wide range of temperatures. The 3M company, for example, offers a two-component construction adhesive especially suitable under the Scotch-Weld 9323B / A brand. In order to produce an adhesive joint with the greatest possible strength, it is particularly advantageous if the adhesive surface of the support element is machined on its surface in a suitable manner before applying the adhesive, for example, when polishing the corresponding adhesive surface, so that the adhesive surface has a peak-to-valley height of about 50 μm to 100 μm. The use of the sills according to the present invention in the manufacture of a guide for the air cushion supports has resulted in the fact that there is a transition area between the adjacent sills. With high-precision production and installation of the sills, this transition area can be created so that the size of the resulting joints does not interfere with the operation of the air cushion supports. However, it is extremely difficult to produce and install the sills in the support element in such an accurate manner. According to a preferred embodiment, a hardenable filler material is provided in the transition area between adjacent sills. In the manufacture of the guide, the sills are first secured to the support element, for example, by sticking them permanently, and then the joints between the adjacent sills are filled with the hardenable filling material. After the filler material has hardened, it can be machined along the surface along with the hearth material to produce a guide having an adequate surface quality, in particular an appropriate flatness characteristic. The grinding and polishing have proved to be especially useful as machining methods for the surface machining of the screeds and / or the filler material. The peak-to-valley height of the preferential guide must be less than or equal to 1μm. The flat characteristic of the preference guide must have a deviation less than or equal to 2 μm, for a distance of 200 mm. In order to produce a support structure of the second component that supports the guide, finally all of these materials can be selected from materials that have sufficient stiffness and stability and that can be permanently coupled with the sills forming the guide in an appropriate manner. In particular, the welded structures of steel parts have proved to be especially suitable for producing the second support component of the guide. Such steel structures are economically manufactured and in particular, they can be manufactured in a relatively short time and without major tool investment costs, in particular without dies. In addition, steel structures allow the engineer to use multiple different construction measures. The steel structure can be improved with respect to its stiffness, design stability against changes in temperature and adequate dynamic strength in accordance with the desired use of the device, for example, as a measuring machine. The steel parts to produce the welded structure, preferably, are produced by laser cutting (adapted floorings). By laser cutting, the steel material is exposed only to minimum thermal stresses and therefore, has minimum thermal strain strains. The laser welding preferably is used as the welding technique to join the different steel parts. The joints with high precision can be produced by laser welding, and again, the steel parts are exposed only to minimum thermal stresses. In order to reduce the deformation of the second component that supports the guide after the welding, due to the deformation stresses, in accordance with a preferred embodiment, a low-voltage annealing can be carried out in the second component after welding . After the welding and / or the annealing of the second component, the surface treatment in the steel structure can be carried out preferably. By means of a pressurized sand blast or some similar method, the steel structure can be freed of scales and other unwanted substances adhered to it.

In addition, a corrosion resistant surface can be applied, for example, a chrome plating. In order to be able to pre-assemble the steel parts so that they fit exactly with the least effort before welding, it is especially advantageous to provide tongue and groove elements in the steel parts. The steel parts can then be assembled with the proper fit by these tongue and groove elements before welding. Essentially, it does not matter the design used for the inventive device, which has an air cushion support. However, many advantages are achieved with the novel construction of air cushion carrier guides in measuring machines, especially in a coordinate measuring machine. Such measuring machines have at least one measuring head, which is mounted movably in the machine and which can be adjusted by a remote control by means of appropriate activation elements. The measuring head is suitable for measuring workpieces and has appropriate measuring means to do so. According to a preferred embodiment, the measuring machine is designed in the form of a portal machine, which has at least two vertical connections and one horizontal beam. Such portal measuring machines could be manufactured with relatively small dimensions because the required components were not available with sufficient size due to the nature of the materials used. By using the inventive design principle, measuring machines and especially portal measuring machines can be produced in almost any desired size.

BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the inventive device is shown schematically in the drawings and is described in more detail below.

Figure 1 is a perspective view of a device designed in the form of a measuring machine. Figure 2 is a perspective view of a horizontal beam of the measuring machine in accordance with Figure 1. Figure 3 is the design of the guides of the air support in the horizontal beam according to Figure 2, in a Perspective view.

DETAILED DESCRIPTION OF THE INVENTION Figure 1 shows a perspective view of an inventive device 01 designed in the form of a coordinate measuring machine. Machine. Measurement 01 has an independent surface 02 where the workpiece to be measured is placed and which can be made of a granite block. As an alternative, the independent surface 02 may also be formed of a steel construction part equipped with ceramic sole plates. Two support and drive devices 03 and 04 are arranged next to the independent surface 02, with the operating elements of the support and drive devices 03 and 04 covered by a housing. A portal 05 is supported in the support and drive devices 03 and 04 and can be moved horizontally through the independent surface 02 by means of the actuating means in accordance with the movement arrow 06. The portal 05 is made of two vertical connections 07 and 08 and a horizontal beam 09. A carriage 10 is supported on the upper side of the horizontal beam 09 with a sleeve 11 of vertical axis coupled with the carriage. A measuring head of the measuring machine 01 is coupled to the lower side of the vertical axis sleeve 11, the workpiece, placed on the independent surface 02, can be measured with this measuring head. The carriage 10 can be moved horizontally in accordance with the arrow 12 of movement on the independent surface 02 on the horizontal beam 09 by means of the drive means (not shown in detail). By inserting and retracting the vertical axis sleeve 11, the measurement head can be moved vertically according to the movement arrow 13. As a result, the measuring head can also be freely positioned by moving the portal 05 and the carriage 10 in the horizontal plane and can be placed in height when removing and retracting the vertical axis sleeve 11. Therefore, the measuring head can approach all the points in the space defined by the size of the independent surface 02 and the cross section of the portal 05.

To support the parts of the measuring machine 01, which are movable relative to one another, the air cushion support elements 14 are provided, these elements cooperate with the corresponding guides 15 for a non-contact and guide support of the components that can move one in relation to the other. The compressed air flows at an appropriate air pressure along the circular ring-shaped bottom side of the air cushion support elements 14 (see Figure 3) and ensures that the air cushion support elements 14 are suspended on the guides 15 with an air gap of a few micrometers. The moving components of the measuring machine 01 are guided and supported in a non-contacting manner. The design of the horizontal beam 09 is shown on an amplified scale in Figure 21 The horizontal beam 09 obtains its mechanical strength from a component 16 of welded construction, which is manufactured by laser welding various steel parts 17 that are produced by laser cutting. Each of the steel parts 17 has a tongue and groove connection to allow pre-assembly of the steel parts 17 when joining them before laser welding. To achieve the least possible deformation with temperature, the welded construction component 16 has a plurality of recesses in the steel parts 17. To form the guides 15, the component 16 has two prismatic guide beams 18 and 19 on the upper side, the ceramic sole plates 20 are glued on the respective respective upper and outer sides (see Figure 3) to form the guides 15. Each one of the guides 15 in the guide beams 18 and 19 are aligned at right angles to each other, so that as a result, the carriage 10 can be guided both horizontally and vertically with precision. The design of the guides 15 is shown again in Figure 3, at an amplified scale. An adhesive 22 is applied to the adhesive surfaces 22 of the welded construction component 16 to mount the ceramic sills 20, then the sills 20 are glued onto the layer formed by the adhesive 22. After the adhesive 22 hardens, the areas 23 transition between the neighboring sills 20 are filled with a hardenable filler material. After the filler material hardens, the screeds and filler material are machined by their surface by appropriate finishing methods, for example, grinding and polishing along the guides 15 to establish the peak-to-valley height and the Flat feature required.

Claims (20)

1. A device (01) having at least two components (09, 10) that can be moved relative to each other, at least one air cushion support element (14) is provided in the first component (10) , so that it cooperates with a guide (15) provided in the second component (09), so that the first component (10) is guided and / or supported in the second component in a non-contacting manner with the air space between the air cushion support element (14) and the guide (15), characterized in that: the guide (15) is made of sills (20) that engage with the second component (09) side by side.

The device according to claim 1, characterized in that the sole plates (20) are made of a ceramic material, in particular of Stettalit, having the ceramic number C221 according to VDE 0335 part 3.

3. The device according to claim 1 or 2, characterized in that the sole plates (20) are coupled with an adhesive surface (21) of the second component (09) with the use of an adhesive (22).

4. The device according to claim 3, characterized in that the adhesive (22) has a low flow capacity.

The device according to claim 3 or 4, characterized in that a two component construction adhesive is used as the adhesive (22).

The device according to any of claims 3 to 5, characterized in that the adhesive surface (21) of the second component (09) has a peak-to-valley height of about 50 μm to 100 μm before applying the adhesive ( 22).

The device according to any of claims 1 to 6, characterized in that the hardenable filler material is provided in the transition area (23) between the adjacent headers (20).

The device according to any of claims 1 to 7, characterized in that the areas of the sole plates (20) and / or the filling material forming the guide (15) are machined on its surface, in particular by grinding and / or polishing after the filling material and / or the adhesive has hardened.

9. The device according to any of claims 1 to 8, characterized in that the guide (15) has a peak-to-valley height less than or equal to 1 μm.

The device according to any of claims 1 to 9, characterized in that the guide (15) has a flat characteristic less than or equal to 2 μm / 200 mm.

11. The device according to any of claims 1 to a. 10, characterized in that the second component (09) is manufactured as a multi-part welded construction (17) of steel.

The device according to claim 11, characterized in that the steel parts (17) are produced by laser cutting.

13. The device according to claim 11 or 12, characterized in that the steel parts (17) are joined by laser welding.

The device according to any of claims 11 to 13, characterized in that the low-voltage annealing is carried out in the second component (09) after welding the steel parts (17).

The device according to any of claims 11 to 14, characterized in that the second component (09) is treated on its surface, in particular with sandblasting under pressure and / or with a corrosion-resistant coating, after of the soldier or after annoying.

16. The device according to any of claims 11 to 15, characterized in that tongue and groove elements are provided for the pre-assembly of the steel parts (17) to be joined.

The device according to any of claims 1 to 16, characterized in that the device (01) is designed in the form of a measuring machine, in particular a coordinate measuring machine having a mobile measuring head for measure work pieces.

18. The device according to claim 17, characterized in that the measuring machine (01) has at least two vertical connections (07, 08) and a horizontal beam (09) supported on the vertical connections (07, 08), so which, the vertical connections (07, 08) together with the horizontal beam (09) form a portal (05) on an independent surface (02) where the workpiece to be measured can be supported. The device according to claim 18, characterized in that the vertical connections (07, 08) have a vertical length in the range of approximately 0.5 meters to 5 meters, in particular, 1.2 meters. The device according to claim 18 or 19, characterized in that the horizontal beam (09) has a horizontal extension between the vertical beams within the range of approximately 0.5 meters to 5 meters, especially 1.5 meters.