Dynamic feeler head.

p0001The invention relates to a dynamic probe for measuring machines and for use in machine tools for solving measurement tasks according to the preamble of claim 1.

p0002From DE-PS 32 34 851 discloses a such dynamic probe for measuring machines is known in which a package of five superimposed and equipped with the same lever arms plates is provided, which are mutually articulated at their side edges, so that a power flow in a certain way is complied with. The superposed plates of known probe are rigid metal discs. The hinges at the lateral edges are formed by at right angles to the plates arranged leaf springs. In this known probe has been found that the components cost is relatively high and the items must be carefully assembled by relatively complex and precise individual preparation, so that the desired accuracy of the probe is guaranteed. In addition, each two plates can be made to the leaf spring joints possible displacement of the stylus only in a relatively high force.

p0003From DE-PS 26 20 099, a measuring head is known which in the three coordinate directions movable measuring calipers is equipped with and are provided at the leaf spring joints with cascaded leaf springs.

p0004From US-PS 4,553,332 a sensing device for measuring linear dimensions is known which is equipped with a support and having a sensor to a supporting movable arm. A one-piece component provides the connection between the support and the movable arm. This one-piece component having a first, a second and an intermediate portion which are separated from one another by incisions and holes and are relatively narrow webs with each other. This one-piece component as the core of the sensing device has a relatively bulky and is structured technically complex and complicated. The Meßkontaktgaben are possible through contact points on movable portions and require constant spring support. Although said body appear large and bulky, it is still due to the many cuts and holes in different planes and directions an unstable structure.

p0005Starting from the aforementioned prior art, the object of the invention to provide a dynamic probe of the aforementioned type, which is composed of only few individual components and in the coordinate directions X and Y both defined and relatively slight deflection forces and good reproducibility of movements comprises the entire probe, and wherein a displacement of the individual sheets is avoided.

p0006This object it is inventively achieved by the features in the characterizing part of claim. 1 Inventive embodiments are found in the dependent claims 2 to 18th

p0007The particular advantage of this solution is that the three lying between the two outer discs plates are designed as leaf springs, which are connected at their outer edges together articulated. This configuration eliminates the customarily attached to the side edges of the leaf spring joints for the deflection of the probe. In addition, the height of the superposed discs because of the leaf springs used is extremely low. The leaf spring discs are at their the interconnection serving side edges by welding, for example laser welding, fixed to what their displacement to each other to prevent and contributes to stiffening in the deflection. Through the use of pins, which dip into bores of the superimposed constructed leaf springs, a constant centering of the probe for a probe process takes place in an advantageous manner.

p0008The particular advantage of the spring block integrally formed according to claim 5 and following is that the entire spring block for the deflection of the probe in the X and Y coordinate directions is made of a single piece. Since the parallel in the X and Y planes cuts the spark erosion process are very thin, builds the entire spring block high only a few millimeters. A shift of the individual leaf spring washers each other is excluded. The one-piece block is a relatively rigid structure, which precisely deflections of the probe allowed in the coordinate directions and to torsion.

p0009In development of the invention, the lowermost joint be designed as a web which is attached to the fifth wheel by screws.

p0010A particularly advantageous development experienced by the probe in that on the leaf spring washers facing surface of the fifth wheel four carbide pins are firmly applied the interposition of an insulation which is on a common circular ring and coaxially with the hard metal pins in all superimposed disks attached through holes are arranged and abut pressed into the through holes carbide balls in the rest position of the probe. The hard metal pins can be glued to the surface of the fifth wheel. The cemented carbide balls can further comprises a layer of electrically conductive material, such as nickel or gold have. In the hard metal pins also may be provided transverse bores. In support of the balls on the hard metal pin, an electrical contact is closed, which is noted in the evaluation. Once the stylus touches to a workpiece and thereby undergoes a deflection on the leaf spring washers, the contact between a sphere and a holding pin is interrupted, which leads to a signal in the evaluating unit. In the cross holes of the hard metal pins, for example, terminals can be inserted, whereby an electrical connection is possible between the hard metal pin and the evaluation unit.

p0011Finally, the first disk can be connected to a receiving body for the sensing pin, the cylindrical body extends through centrally disposed apertures in the disks, while the top plate is under the effect of a on the housing of the probe head supporting spring.

p0012In the drawing embodiments of the invention are shown. Show it:<ul><li>FIG. 1 is a simplified illustration of a probe head with pivotally interconnected leaf spring washers;</li><li>FIG. 2 shows the probe of Figure 1 in an enlarged side view. </li><li>Figure 3 shows the probe in the 90 ° rotated side view according to the direction of the arrow III in Figure 2..;</li><li>Figure 4 is a plan view of the probe according to the arrow IV in FIG. 3. FIG.</li><li>Figure 5 is a simplified illustration of a probe head with integrally hinged leaf spring discs in a side view.</li><li>Figure 6 is a side view of the probe according to the direction of the arrow VI in FIG. 5. FIG.</li><li>Figure 7 shows a detail of the probe of Figure 5, partly in section..;</li><li>Fig. 8 is a plan view of the lower disk of the probe according to the line VIII-VIII in Fig. 7.</li></ul>

p0013The probe 1 is installed in a housing 15 and has a centrally disposed push button 2. The entire probe head 1 consists of a package of five superposed plates 3, 4, 5, 6, 7 and 3 ', 4', 5 ', 6 ', 7', which are mutually connected via hinges 8, 9, 10, 11 or 8 ', 9', 10 ', 11' at their side edges. This means that, upon deflection of the stylus 2 in one of the coordinate directions X, Y, the plate pack of the probe head 1 tilts about an axis extending at the side edges of the plates tilting axis.

p0014In detail, the structure of the probe 1 according to the figures 1 to 4 is made so that an upper fixed disc 3 of a rectangular cross section at one side edge, the second disk 4 receives, which is formed as a leaf spring. This leaf spring disk 4 is secured by a web 14 to the upper plate 3 by screws 17th This attachment at the same time forms the first joint 8 with the tilt axis along the side edge 18 of the plate 3. Opposite this joint 8 is a second hinge 9, which is formed as a cylinder which extends along the side edge 19 of the leaf spring 4th This cylinder is slit parallel to its longitudinal axis, so that the side edge 19 of the leaf spring disk 4 can be clamped in the joint. The third disc 5 is again designed as a leaf spring and also inserted into the cylinder of the joint 9 in addition to the leaf spring disk 4 and simultaneously welded to its side edge with the side edge of the leaf spring disc 4th The two leaf spring washers 4 and 5 are thus clamped in a single, common, cylindrically shaped hinge 9th offset by 90 ° to the hinge 9 is located on the side edge 20 of the leaf spring 5, in turn, a joint 10 which is also formed as a cylinder, which is slit open along the side edge 20 of the leaf spring disc fifth

p0015In this slot of the cylinder, the side edge of the other leaf spring 6 is clamped, which is also attached at the opposite end from the hinge 10 by a web 14 with screws 17 hinged on the lower plate 7th The side edges of the leaf spring washers 5 and 6 in the joint 10 are also to each other by welding, for example laser welding, immovably connected to each other.

p0016By this arrangement of the two outer rigid disks 3 and 7 used as a package and each hinged leaf spring washers 4, 5 and 6 results in the following power flow in deflection of the probe 2 in the coordinate directions X and Y:

p0017From the upper rigid disk 3, the force passes through the joint 8 to the leaf spring disk 4 and from this leaf spring disk 4 via the the joint 8 directly opposite hinge 9 to the further leaf spring washer 5. From this the force flow continues through the 90 ° to the hinge 9 staggered joint 10 on to the next leaf spring disc. 6 From there, the power flow through the said hinge 10 again opposed last joint 11 on the lower rigid plate 7 extends.

p0018From the exemplary illustration it can be seen that the lever arms of the switch 2 on all four sides are always the same length. The button 2 is always tilts about an axis parallel to the coordinate directions X or Y running side edge of a plate or leaf spring disc. This ensures a very precise tipping in the coordinate directions. By between the two outer pulleys 3 and 7 arranged leaf spring washers 4, 5 and 6, a relatively soft tilting of the stylus about the tilting axes is possible, wherein the Abkippmoment can be varied by appropriate spring rates of the leaf spring washers 4, 5, 6th

p0019To produce a defined deflection force in the coordinate directions X and Y are in accordance with the example in Fig. 1, the superposed discs 3, 4, 5, 6 and 7 are arranged by four at the plate corners and kept at train loaded springs 16 in the rest position.

p0020In order to ensure the same initial position of the individual disks after each probing of the probe 2 on a workpiece and a corresponding deflection process for the probe head over and over again, a total of three mutually arranged distributed pins 13 are in the outer plate 3 is fixed, which downwardly toward the outer plate 7 immerse in and projecting coaxially with one another arranged holes 12 of the leaf spring washers 4, 5 and 6. FIG. These bores 12 are opposite the pins 13 of a larger diameter so as not to interfere with the tilting of the probe 2 via the respective joints.

p0021The return of the push button 2 takes place substantially by the leaf spring washers 4, 5 and 6 in the joints 8, 9, 10 and 11 and is supported by the attached at the four corner points of tension springs sixteenth

p0022The deflection of the probe 2 in the Z coordinate direction is carried out against the force of an inserted spring 45 which is supported in the housing 15 of the probe. 1 For this, the deflection of the probe 2 in the Z direction may be limited at the top by a stop in the housing 15th

p0023The formation of the discs 4, 5, 6 as leaf springs and their particular arrangement at an angle of 90 ° to each other has the great advantage that the leaf spring discs themselves form relatively long spring-lever arms and that their stress always occurs along the grain of the material. This has the consequence that, with a stationary object takes a resilient deflection of the stylus 2 in collisions without causing permanent deformation of the leaf spring washers 4, 5, 6 or their joints 8, 9, 10, 11 occurs.

p0024Thus, the effectiveness and operability has been compared with the probe according to DE-PS decisively improved in particular 32 34 851 inventive manner.

p0025In place of the welding of the leaf spring washers 4, 5, 6 can also occur any other solid compound according to the invention, such as rivets, screws, glue or the like. The same applies to the connection of the side edges of the leaf spring discs 4 and 6 with the outer discs 3 and 7. It can be chosen instead of the screw connection, welding, riveting or gluing. It is crucial that the discs 3, 4, 5, 6, 7 are immovable in operation with each other, so that always reproducible deflections of the push button 2 are possible. the slotted cylinder also have the function of the protective cap for the side edges of the leaf spring washers and a stiffening taken so that the deflection is always exactly in one direction and remain undefined transverse movements of the leaf springs.

p0026With respect to the three pins 13 is still run, that they form not only centering of the leaf spring washers 4, 5, 6 and ensure their correct position above each other after the displacement, but also a three-point support of the discs 3, 4, 5, 6, 7th

p0027According to figures 5 to 8, an advantageous and proven in testing alternative of the probe 1 is shown.

p0028In this alternative solution, the probe 1 is installed in a housing 15 and connected to housing 15 by bolts 30th The probe 1 has a centrally located switch 2, which is inserted in a receiving body 27, standing with his head disc 42 in the Z direction under the action of a spring 28 which is supported on the housing 15th The entire probe head 1 consists of a package of five superposed discs 3 ', 4', 5 ', 6', 7 ', which via joints 8', 9 ', 10', 11 'joined at their side edges to one another in one piece with one another , This means that during the deflection of the probe 2 in one of the coordinate directions X, Y, the plate pack of the probe 1 in a groove extending at the side edges of the disks tilting axis tilts.

p0029In detail, the construction of this probe 1 according to the figures 5 to 8 is carried out so that an upper fixed disc 3 'of rectangular cross-section across the joint 8' on one side edge to the second leaf spring plate 4 'is integrally connected. The leaf spring disc 4 'is in turn over the joint 9' integrally connected to the further leaf spring disk 5 '. Finally, a further one-piece connection between the leaf spring disk 5 ', and the leaf spring 6' via the joint 10 ', which by 90 ° to the hinge 9' is rotated. To the leaf spring 6 'finally followed by a further joint 11' to which 6 'opposite to the joint by 180 °. This spring block is made in one piece formed by cuts 21, 22, 23 and 24 are made zwischem the individual disks. These cuts are preferably made in the EDM machining process. This creates a very thin cut of high precision is possible, whereby a plate package of exactly aligned parallel to one leaf spring discs produced. The overall height of this formed from spring washers spring assembly is for example only 6 to 7 millimeters. The 180 degrees around opposite joints 8 'and 9' as well as the 90 ° offset joints 10 'and 11' allow an exact alignment of the probe in the X and Y directions. The discs 3 ', 4', 5 ', 6' and 7 'have a central opening 25 into which the cylindrical part 27 of the receiving body 26 extends for the probe second The receptacle body 26 'is connected to the upper plate 3 by screws 31st The compound of the leaf springs 3 ', 4', 5 'and 6' with the bottom plate 7 'is again carried out by means of screws 32, which in the hinge 11' are inserted.

p0030On the surface 29 of the lower plate 7 'are located on a common circle ring 35 four equally spaced carbide pin 36, the interposition of an insulation 37 with the disc 7' are joined by gluing. In the cemented carbide pin 36 transverse bores 38 are provided into which a cable lug or a cable pin 44 can be inserted in a contacting, which is connected via a connecting line 33 having a Meßwertauswerteeinrichtung 34th There are only three carbide pins 36 used.

p0031The hard metal pin 36 are in the rest position of the probe 1 with hard metal balls 39 in contact. These balls 39 are in through holes 40 of the disks 3 ', 4', 5 'and 6' is pressed, which are in alignment with the koaxialier carbide pin 36th The hard metal balls 39 have a contact shell surface such as nickel or gold. In one touching the button 2 on a workpiece 41 the probe 2 undergoes a deflection in the X- and Y-direction with a contact between a hard metal pin 36 and a tungsten carbide ball 39 dissolves. Thus, the contact is broken and produces a signal in the evaluation unit 34, which represents a measured value.

p0032From the view of the spring assembly of the figures 5 to 8 it can be seen that the lever arms from the button 2 on all four sides are always the same length. The button 2 is always tilts about an axis parallel to the coordinate directions X and Y running side edge of a plate or leaf spring disc 3 ', 4', 5 'and 6'. This ensures a very precise tipping in the coordinate directions. The return of the push button 2 happens substantially always by the leaf spring washers 3 ', 4', 5 'and 6' in the joints 8 ', 9', 10 'and 11'. the deflection of the probe 2 in the Z coordinate direction is carried out against the force of an inserted spring 28 which is supported on the housing 15 of the probe. 1 Further, the deflection of the probe 2 in the Z direction can be limited at the top by a stop in the housing 15th

p0033The formation of the discs 3 ', 4', 5 'and 6' and their particular arrangement at an angle of 90 ° to each other has the advantage that the leaf spring discs themselves form relatively long spring-lever arms and on the other hand always carried their stress along the grain of the material. This has the consequence that, with a stationary object takes a resilient deflection of the stylus 2 in collisions without causing permanent deformation of the leaf spring washers or their joints occur. Thus, the operability of the effectiveness has been improved in an inventive manner decisively over the prior art une.