WO2010081712A1

WO2010081712A1 - Processing machine

Info

Publication number: WO2010081712A1
Application number: PCT/EP2010/000199
Authority: WO
Inventors: Jörg Evertz
Original assignee: Wieland Dental + Technik Gmbh & Co. Kg
Priority date: 2009-01-16
Filing date: 2010-01-15
Publication date: 2010-07-22
Also published as: DE202009018593U1; DE102009011443A1

Abstract

The invention relates to a processing machine (10) for machining a work piece (32), in particular for machining a blank for producing a tooth replacement part or a denture model, comprising a stationary frame (14), a tool holder (74) that can be automatically moved in relation to the frame (14) for receiving a machining tool (62), and a work piece holder (44) that can be automatically moved in relation to the frame (14) for receiving a work piece (32) being machined. To this end, the tool holder (74) and the work piece holder (44) can be automatically moved in relation to each other in a translatory manner in the direction of a Z-axis. Furthermore, the tool holder (74) can be automatically moved in a rotational manner in relation to the frame (14) about a U-axis that can be aligned or is aligned orthogonally to the Z-axis. According to the invention, the tool holder (44) can be automatically moved in a rotational manner about an A-axis in relation to the frame (14), wherein the A-axis and the U-axis can be aligned in parallel in relation to each other.

Description

description

Bearbeitunqsmaschine

Field of application and state of the art

The invention relates to a processing machine for machining a workpiece, in particular for machining a blank for producing a dental prosthesis part or a denture model, with a fixed frame, an automatically movable relative to the frame tool holder for receiving a machining tool and a relative to the frame automatically movable workpiece holder for receiving a workpiece being processed. In this case, the tool holder and the workpiece holder are automatically translatable relative to each other in the direction of a Z-axis. Furthermore, the tool holder relative to the frame about an orthogonal to the Z-axis alignable or aligned U-axis is automatically rotatably movable.

Generic processing machines are well known from the prior art. In the field of dental prosthesis manufacturing, they are used to make dental prostheses such as crowns, inlays or bridges. These dental prostheses are machined by machining, for example by milling, drilling or grinding, from a blank. The shaping of the tooth replacement parts is achieved in generic processing machines in that the relative position of the rotating tool is continuously changed relative to the workpiece, so that the cutting tool removes material around the tooth replacement part to be produced and thus leave the tooth replacement part with the desired shape. In order to be able to move the tool freely with respect to the blank with respect to its position, it is provided in the case of the processing machines from the prior art that the tool and the workpiece are movable relative to one another transversely along the three basic directions. Thus, in the simplest case, the workpiece can be fixed to the frame while the tool is movable along an X-axis, a Y-axis and a Z-axis relative to the workpiece. In addition, to allow undercuts, the tool can also be pivoted relative to the workpiece.

It is also known from the prior art to be able to rotate the workpiece through 180 ° in order to be able to process successively two opposite sides of the blank.

It is considered disadvantageous in the prior art processing machines that the design of the processing machine with moving devices for moving the workpiece or the tool along the X-axis, the Y-axis and the Z-axis take up comparatively much space. This is disadvantageous particularly in the case of processing machines which are used to produce tooth replacement parts and / or denture models since such machines are preferably designed to be small, so that they can be set up in dental laboratories or medical practices.

Task and solution

The object of the invention is therefore to provide a processing machine which reduces the disadvantages of the prior art and in particular has improved kinematics.

According to the invention this is achieved in that the workpiece holder relative to the frame about an A-axis is automatically rotatably movable, wherein the A-axis and the U-axis are aligned parallel to each other.

As a processing machine in the context of this invention, a machine is considered, which has relatively movable holder for receiving the workpiece on the one hand and the tool on the other hand. These holders, the tool holder and the workpiece holder, can be moved relative to one another automatically in accordance with predetermined processing data, in order to work out the tooth replacement part to be produced from a blank. Processing machines according to the invention have a stationary frame, wherein the local strength with regard to the frame relates to a location stability in relation to a connection region, for example a floor. Compared to this frame, both the tool holder and the workpiece holder are movable to allow a three-dimensional machining of the workpiece. On the one hand, this relative mobility comprises a translatory mobility along the Z axis, so that the workpiece holder and the tool holder can be moved toward and away from each other in the Z direction.

Furthermore, both the workpiece holder and the tool holder are formed automatically pivotable about an A-axis or a U-axis. In this case, the A-axis and the U-axis are immutable either with respect to their orientation and parallel to each other or one of the axes or both axes have a variable orientation, but are convertible to an orientation in which they are aligned parallel to each other and preferably orthogonal to the Z-axis.

The described parallel pivotability of the workpiece and of the tool about the A-axis or about the U-axis is suitable together with the translational movability of the workpiece holder and the tool holder relative to one another in the direction of the Z-axis, a translational movement of the workpiece holder and of the tool holder to each other in the direction of a Y-axis, which is aligned orthogonally to the Z-axis to replace. Thus, the same machining effect that would be achieved by a movement of the tool along this Y-axis, can also be achieved by both the workpiece and the tool are pivoted by an identical angle about the A-axis and the U-axis while at the same time compensating for the resulting approach or spacing of the workpiece from the tool by means of relative movement along the Z-axis. It is thus possible, the processing options resulting from two mutually orthogonal translational degrees of freedom (Z, Y) of the workpiece to the tool, by means of only a translational degree of freedom along the Z-axis and by means of two rotational degrees of freedom about the A-axis or U Replace the axis. A control device of the processing machine may be configured to perform the required coordinate transformation to subsequently replace the Y-axis by the A-axis and the U-axis upon actuation of the respective motors.

It is considered particularly advantageous if, in a processing machine according to the invention, neither the workpiece holder nor the tool holder can be moved in the direction of a Y-axis in a translatory manner relative to the frame, this Y-axis being orthogonal to the Z-axis and oriented orthogonal to the A-axis and the U-axis in their parallel orientation. By eliminating the translational mobility in the direction of the Y-axis, the required installation space and the required complexity of the movement systems for moving the workpiece and the tool are reduced. This is particularly advantageous because the sealing of movable components of the milling machine on rotatively movable components is easier to implement than on translationally movable components. By reducing the translational degrees of freedom of the workpiece holder and the tool holder to a total of only two translational degrees of freedom, only one translational degree of freedom can be assigned to the workpiece holder and the tool holder so that it is possible to provide all linear axes of the translational degrees of freedom in a fixed manner on the frame.

Preferably, the tool holder and the workpiece holder are additionally automatically translatable relative to each other in the direction of an X-axis, wherein the X-axis is aligned orthogonal to the Z-axis. This X-axis is parallel to the A-axis and the U-axis is in parallel alignment. By this design, therefore, the tool holder and the workpiece holder in two directions (Z, X) are mutually translationally movable, while a translational mobility in the direction of the X-axis and the Z-axis orthogonal Y-axis is either not structurally provided or at least by the pivotability of the tool holder about the U-axis and the workpiece holder is replaceable about the A-axis.

In a further development of the invention, the tool holder relative to the frame in addition to a orthogonal to the Z-axis and orthogonal to the U-axis alignable or aligned B-axis is rotatably movable. In such a design, therefore, the tool can be pivoted about two mutually orthogonal pivot axes (B, U), so that additional flexibility in processing is achieved. The pivotability of the tool holder about the U-axis is preferably not exclusively the explained substitution of the Y-axis in cooperation with the pivotability of the workpiece holder about the A-axis. In addition, this pivotability about the U-axis with nichtververenktem workpiece also an employee orientation of the tool relative to the workpiece allow, through which an improvement in the surface quality can be achieved. The same purpose is also the pivotability of the tool to the B-axis. Overall, the two translational degrees of freedom with respect to the X axis and the Z axis and the three rotational degrees of freedom with respect to the A axis, the U axis and the B axis thus result in a 5-axis machining possibility for the workpiece.

With regard to the workpiece holder, a configuration has been found to be particularly advantageous in which the workpiece holder is movable relative to the frame in the direction of the X-axis and is rotatably movable about the A-axis. This double mobility is preferably achieved in that an intermediate element associated with the workpiece holder is translationally movable relative to the frame in the direction of the X-axis, and that the workpiece holder is rotatably movable relative to this intermediate element about the A-axis.

With regard to the tool holder, a configuration has been found to be particularly advantageous in which the tool holder relative to the frame in the direction of the Z-axis is translationally movable and relative to the frame about the U-axis and preferably also about the B-axis rotatably movable. It is particularly advantageous in this case if a first intermediate element associated with the tool holder is movable in translation relative to the frame in the direction of the Z axis and the tool holder is rotatably movable relative to this first intermediate element about the U axis and the B axis. Especially from It is advantageous if a second intermediate element assigned to the tool holder is rotatably movable relative to the first intermediate element about the B axis and the tool holder is rotatably movable relative to this second intermediate element about the U axis.

For the purposes of this invention, a translatory mobility of the tool holder or of the workpiece holder is understood such that the tool holder or the workpiece holder is guided by a guide device oriented in the direction of the corresponding axis. A translatory mobility in the direction of a certain axis is therefore not given if only a common movement along two degrees of freedom leads to a superimposed movement in the direction of this axis. Accordingly, a mobility around the corresponding axis is considered as rotative mobility within the meaning of the invention, in which the corresponding axis is structurally defined, for example by a bearing.

The invention further relates, in particular as a development of the above-described processing machine, and a processing machine for machining a workpiece, in particular for machining a blank for producing a dental prosthesis, with a stationary frame, with a relation to the frame for the purpose of machining automatically movable tool holder and with a respect to the frame for the purpose of machining automatically movable workpiece holder, wherein the tool holder and the workpiece holder are arranged in a common processing space, wherein moreover the tool holder by means of a tool holder associated with the first movement device is automatically movable and wherein, moreover, the workpiece holder means a second movement device associated with the workpiece holder is automatically movable. It is inventively provided that the processing space is completed by a vertically extending rear wall and the two moving devices are mounted on the rear wall or extend through a recess in the rear wall therethrough.

In such a design, which is preferably combined with the above-described design with parallel pivotable workpiece holder and tool holder, a bottom portion of the processing space is free of parts of the moving devices for moving the workpiece holder and the tool holder. Both the workpiece holder and the tool holder are provided on said vertically extending rear wall and either connected directly to this or at least projecting through it into the processing space. This design allows, for example, a very simple cleaning of the processing space, since chips and dust generated during processing need not be removed from the complex moving means, but at least for the most part can be removed from a simply designed processing room floor.

It is particularly advantageous if a permanently installed suction device is provided in a bottom region of the processing space. Such a fixed suction device can be used very effectively for sucking chips and dust due to the fact that the moving devices are not provided in the bottom area. Preferably, for this purpose, a bottom plate is provided with recesses, for example, a perforated plate, under which the suction device is arranged.

In addition to such a suction device or the simple design of the processing room with a manually cleanable bottom plate However, other uses of the invention according to the invention of the moving devices remaining free ground area possible. Thus, it is advantageously possible to provide in this area a feed device that can deliver tools and / or workpieces for the machining process, or a container that collects chips, dust and / or used for cooling the machining process liquids.

Brief description of the drawings

Other aspects and advantages of the invention will become apparent from the claims and from the following description of a preferred embodiment of the invention, which is explained with reference to the figures. Showing:

Fig. 1 shows the processing space of a processing machine according to the invention in a perspective view and

2a to 2e show a side view of the workpiece holder and the tool holder of the processing machine during the machining process and the workpiece after processing.

Detailed description of the embodiments

1 shows the processing space 12 of a processing machine 10 according to the invention. In this processing space 12 are a workpiece holding and moving system 30 (hereinafter: workpiece system 30) with inserted workpiece 32 and a tool holding and moving system 60 (hereinafter: tool system 60). provided with inserted tool 62. The workpiece system 30 has a workpiece carriage 40 which is guided by guide rails 42 by means of a motor, not shown, in the direction of an X-axis automatically movable. A workpiece holder 44 is coupled to this workpiece carriage 40, wherein this workpiece holder 44 is automatically electromotively pivotable relative to the tool carriage 40 by means of an electric motor, likewise not shown, about an A-axis. The workpiece 32 itself is a round, flat blank 32, which can be moved translationally by means of the workpiece system 30 along the X-axis and can be pivoted rotationally about the A-axis.

The tool system 60 has a movable in the direction of a Z-axis tool carriage 70. Compared to this tool carriage 70, a mounting bracket 72 is rotatably pivotable about a B-axis. A tool holder 74 is pivotable relative to this mounting bracket 72 about a U-axis. The workpiece holder 74 comprises a machining spindle 76 which rotates during machining and in which the milling tool 62 is clamped.

For alignment of said axes: In the illustrated processing machine, the X-axis and the A-axis are formed parallel to each other. The Z-axis is orthogonal to the X-axis and the A-axis. The B axis is orthogonal to both the Z axis and the X axis and the A axis. The U-axis has no fixed orientation, but is structurally defined only to the extent that it is always oriented orthogonal to the B-axis and lies on the plane spanned by the X-axis and the Z-axis. When the support bracket 72 is pivoted about the B axis, there is also a displacement of the U axis. It is essential, however, that the variably alignable U-axis can also be aligned parallel to the A-axis, as is the case for example in the state shown in FIG. The processing space 12, in which the workpiece system 30 and the tool system 60 are arranged at least for the most part, is delimited on the back by a holding plate 14. The workpiece carriage 40 is fastened by means of the guide device 42 to this rear wall 14 in a translationally movable manner. Also, the tool carriage 70 is disposed on the rear wall 14. Thus, both the workpiece side and the tool side systems 30, 60 extend from the rear wall 14 and are not mounted in the bottom portion 16 of the processing space 12. The floor area 16 is therefore free of guides or other parts of the systems 30, 60. In this floor area 16 a bottom plate 18 is provided, which has a plurality of suction openings 19, of which some are shown by way of example. In a manner not shown, a suction device is provided below this bottom plate 18, which sucks dust and chips from the processing chamber 12 by generating a negative pressure.

As can be seen from the discussion of the various degrees of freedom of the tool and the workpiece, neither the tool 62 nor the workpiece 32 can be translationally moved in the direction of an orthogonal Z-axis and X-axis aligned Y-axis. Since a relative movement of the workpiece to the tool according to a movement along such a Y-axis, however, is required for complete processing of the workpiece 32 for the production of dental prostheses, this movement in the direction of the Y-axis by a superimposed movement of the workpiece 32 rotatably around the A -Axis and the tool 62 rotatably about the U-axis and translationally replaced along the Z-axis. This substitution will be explained below with reference to FIGS. 2a to 2e.

2a to 2d shows a schematic view of the tool system 60 and the workpiece system 30 from the side, so that the viewing direction is parallel to the X-axis. To clarify the kinematics of Processing machine 10 will be described below as how a groove of constant depth is introduced into the workpiece 32, which extends from the center of the workpiece 32 to the outside.

In a system where either the workpiece or the tool is moveable by a corresponding degree of freedom in the direction of the Y-axis, said groove would be made by lowering the tooling system 60 in the Z-axis direction, followed by relative movement of the tooling system Workpiece system in the direction of the Y-axis. However, since the processing machine 10 is formed without translational mobility of the workpiece or the tool in the Y direction, the Y axis is replaced by the axes A, U.

Fig. 2a shows an initial state in which the tool 62 is aligned in the Z-axis direction. This is effected by a corresponding pivotal position of the tool holder 74 with respect to the U-axis and the B-axis (U = B = 0 °). The workpiece 32 is also not pivoted in this state of Fig. 2a, so that a surface normal 32a is also aligned in the Z-axis direction. Without pivoting the workpiece 32 or the tool 62, starting from the position of FIG. 2 a, only machining of the blank 52 along its center line extending in the direction of the X-axis is possible.

Starting from the state of FIG. 2 a, first the tool system 60 and thus also the milling tool 62 are lowered in the direction of the Z-axis, so that the state of FIG. 2 b is achieved. In this case, the tool 62 has penetrated vertically into the workpiece 32 and in this case has removed the material of the workpiece 32 located there. In order to guide the tool 62 outward in the direction of extension of the workpiece 32 after this penetration, both the tool holder 74 and the workpiece 32 are pivoted about identical angles about the axis U or A (U = A). At the same time, the tool system 60 is slightly raised in the Z-axis direction. FIG. 2c shows the processing state after simultaneous pivoting of the workpiece 32 and the tool 72 by 5 ° as well as a lifting of the entire tool system 60 by about 8.5 mm. This superimposed movement causes the tool 62 to move outwardly with respect to the workpiece 32, without the depth of immersion of the tool 62 having changed relative to the workpiece 32.

FIG. 2d shows a continuation of the superimposed motion already explained in FIG. 2c. The workpiece 32 and the tool 62 are now pivoted by 10 ° relative to the position of Fig. 2a. Meanwhile, the tooling system 60 has been raised by about 18 mm from the position of FIG. 2b to compensate for the approximation of the workpiece 32 and the tool 62 caused by the pivoting and thus to prevent the resulting groove from becoming outwardly an increasing depth receives.

Fig. 2e shows the workpiece 32 and the groove 33 produced therein after machining. It can be seen that the groove has the same shape, which can also be achieved by a translational displacement of the submerged tool in the direction of the Y-axis. However, the production was made without movability of the workpiece 32 and the tool 62 in the direction of the Y-axis. The illustrated design thus allows a complete substitution of the mobility of the workpiece or the tool in the direction of the Y-axis. The axes A and U required for this substitution are structurally less expensive and much better to protect against contamination. In addition, the Axes A and U as well as the axis B are additionally used to realize an alignment of the tool 62 to the workpiece 32, in which the tool 62 is no longer aligned parallel to a surface normal 32 a on the workpiece 32. Here, improved surfaces can be created because the tool 62 can be tilted relative to the workpiece 32.

Claims

claims

1. Processing machine (10) for machining a workpiece (32), in particular for machining a blank for producing a dental prosthesis part or a denture model, with a stationary frame (14), an opposite the frame (14) automatically movable tool holder (74) for receiving a machining tool (62) and a workpiece holder (44), which is automatically movable relative to the frame (14), for receiving a workpiece (32) being processed, wherein the tool holder (74) and the value holder (44) move in the direction of one another relative to one another The Z-axis is automatically translatively movable and the tool holder (74) relative to the frame (14) about an orthogonal to the Z-axis alignable or aligned U-axis is rotationally movable, characterized in that the workpiece holder (44) relative to the Frame (14) is automatically rotatably rotatable about an A-axis, wherein the A-axis and the U-axis parallel to each other el are alignable.

2. Processing machine according to claim 1, characterized in that the tool holder (74) relative to the frame (14) about an orthogonal to the Z-axis and orthogonal to the U-axis alignable or aligned B-axis is rotatably movable.

3. Processing machine according to claim 1 or 2, characterized in that the tool holder (74) and the value holder (44) to each other in the direction of an X-axis are automatically translatable, wherein the X-axis is aligned orthogonal to the Z-axis.

4. Processing machine according to one of the preceding claims, characterized in that neither the workpiece holder (44) nor the tool holder (74) in the direction of a Y-axis are translationally movable relative to the frame, said Y-axis orthogonal to the Z-axis and orthogonal is aligned to the A-axis and the U-axis in their parallel orientation.

5. Processing machine according to one of the preceding claims, characterized in that the workpiece holder (44) relative to the frame (14) in the direction of the X-axis is translationally movable and relative to the frame about the A-axis is rotatably movable, wherein preferably a the workpiece holder (44) associated intermediate element (40) relative to the frame (14) in the direction of the X-axis is translationally movable and the workpiece holder (44) relative to this intermediate element (40) is rotatably movable about the A-axis.

6. Processing machine according to one of the preceding claims, characterized in that the tool holder (74) relative to the frame (14) in the direction of the Z-axis translationally movable and relative to the frame about the U-axis and preferably about the B-axis rotatably movable is, wherein preferably a tool holder associated with the first intermediate element (70) relative to the frame in the direction of the Z-axis is translationally movable and the tool holder (74) is rotatably movable relative to this first intermediate element (70) about the U-axis and the B-axis, wherein, in particular, a second intermediate element (72) associated with the tool holder (44) preferably surrounds the first intermediate element (70). Axis is rotatably movable and the tool holder (74) relative to this second intermediate element (72) is rotatably movable about the U-axis.

7. processing machine (10), in particular according to one of the preceding claims, for machining a workpiece (32), in particular for machining a blank for producing a dental prosthesis part or a denture model, with a stationary frame (14), one with respect to the frame ( 14) for the purpose of processing automatically movable tool holder (74) and a relative to the frame 814) for the purpose of machining automatically movable workpiece holder (44), wherein the tool holder (74) and the workpiece holder (44) arranged in a common processing space (12) the tool holder (74) is automatically movable by means of a first movement device (70, 72) associated with the tool holder (74) and the workpiece holder (44) is automatically movable by means of a second movement device (40, 42) associated with the workpiece holder (44), characterized in that the processing space (12) extend vertically through one the back wall (14) is completed and the two movement devices (70, 72, 40, 42) are attached to the rear wall (14) or extend through a recess (15) in the rear wall (14).

8. Processing machine according to claim 7, characterized in that in a bottom region (16) of the processing space (12) is provided a permanently installed suction device.