WO1988002471A1

WO1988002471A1 - Height measurement device

Info

Publication number: WO1988002471A1
Application number: PCT/CH1987/000127
Authority: WO
Inventors: Eberhard Armbruster; Antonio Soriano
Original assignee: Wenzel Präzision GmbH
Priority date: 1986-10-03
Filing date: 1987-09-30
Publication date: 1988-04-07

Abstract

The base has a vertical symmetrical axis and, in the middle of its lower side, a depression into which leads an air inlet passage and from which an air outlet passage leads to a pressure-regulating nozzle. The base carries a vertical support (20) having a double T section, said support carrying a vertical column (22) in the form of a four-sided section for a slide (4) with a feeler (5) and for a counterweight. Passing over deflection rollers are strips (9, 10) one for tension and the other for counter-tension, said strips being linked with the slide (4) and with the counterweight. The support (20) carries a support element, and on this an adjustable and securable holder which forms a sliding support for the upper end of the column. At least the column (22) for the slide (4) is supported on the base via a ball-cup linkage. The slide (4) carries the bearing races (40) on ball bearing supports (42, 43), from which the first (42) can be set and secured in a rolling, pitching and lurching direction, and the second (43) are arranged movably in a rolling, pitching and lurching direction and are elastically loaded towards the column (22). In this way only two mutually adjacent lateral faces of the column (22) need to be of maximum possible accuracy.

Description

Height gauge

The invention relates to a height gauge according to the preamble of claim 1.

A height gauge of the type mentioned is used to determine the height of a measuring point above a reference plane, which is usually the surface of a measuring table, with the highest possible accuracy on a measurement object. The measurement is carried out with the aid of a slide that moves along a guide track. The measuring distance is the same as the path covered by the sled on the guideway, it is a 1: 1 image of the height to be measured, i.e. the length of the perpendicular drawn from the measuring point to the reference plane.

If the height of the measuring point can be determined, the height difference between two measuring points can also be determined. Nowadays, the accuracy required by a height gauge is around 3 / um.

To achieve such a high level of accuracy of the height measuring gauge, the main problem is to provide a straight vertical guideway for the slide and to arrange it normal to the horizontal reference plane. The main problem mentioned can be broken down into various sub-problems, but the accuracy achieved depends on the solution of all these sub-problems, i.e. the solutions to the sub-problems are not separate and independent of one another, but interact with one another.

A partial problem consists in the exact mounting of the height measuring gauge on the measuring table in the static case and in the dynamic case.

A conventional solution is storage based on the tripod principle. The base of the height gauge is attached to the supported at three points. Although these three points can be arranged in such a way that they define a rather large support triangle, the contact area of the three legs that can be reached with them is very small, which leads to a high load on the material of the base and also on the measuring table. With the three-leg principle, it is still possible to immerse the base in the unevenness in the measuring table, despite the large area spanned by the support triangle, since the immersion of just one leg tilts the base as a whole.

An attempt was therefore made to relieve the load on the material and to provide extensive support by mounting the height gauge on an air cushion. However, because of the necessarily small nozzles, this requires a high supply pressure and a high flow velocity of the air. It is therefore not possible to control the air distribution in such a way that the position of the measuring section relative to the reference plane remains constant with the required accuracy: the height gauge is open Canting susceptible. In addition, the base of the height gauge has to be periodically lapped due to the uneven wear, which still occurs due to the so-called slipping despite air cushions, which is extremely expensive.

In the case of conventional height gauges, the perpendicularity of the measuring path to the reference plane can therefore only be readjusted with reasonable effort with a support according to the tripod principle, the disadvantages of which have been stated above.

As a further disadvantage of a support based on the tripod principle, it should also be mentioned that it is particularly sensitive to deformations caused by uneven heating. Since the height measuring gauge usually includes integrated evaluation electronics, the supply transformer of which develops heat due to the power loss, This evaluation electronics together with the transformer must not be attached to the base.

Another sub-problem is the exact mounting of the guideway for the slide on the base in the static case and in the dynamic case.

A conventional solution consists in the design of the guide track for the slide as a guide profile or guide plate and in the attachment of this guide track to the stand with the aid of a larger number of screws. These screws must not be tightened tightly, otherwise there will be tensions that deform the guideway. Tightened screws also lead to deformations due to the thermal dimensional changes of the guideway and the stand. Only slightly tightened screws can loosen completely. In the end, the conventional fastening of the guideway to the stand with the aid of a larger number of screws leads to a very poorly defined state of tension. However, one has to accept this, because for practical reasons (cost, weight) it is out of the question Solving the guiding problem with a solid individual part, which is able to take over both the function of the stand as a supporting part and the function of the guideway for the slide, it also being practically impossible to adjust the perpendicularity of the guideway to the reference plane.

As a carrier of the guideway, the stand must therefore be designed as much as possible so that it has a high degree of rigidity and its geometry remains as unaffected as possible by the various forces that arise in the static and dynamic cases. A conventional solution consists in forming the stand with three plates welded together, one of which carries the guideway. But this creates an asymmetrical construction that is also asymmetrical is stressed, so that tensions arise that are reduced over time via deformations.

Another sub-problem is to reduce to a minimum the inaccuracies which are caused directly by the guideway and by the slide. Such inaccuracies produce pitch, roll and roll movements of the slide during its movement along the guideway in a certain direction and when the direction of movement is reversed (so-called tipping over). A hysteresis is also noticeable when the direction is reversed.

A variety of inaccuracies can be attributed to the rolling bearings. Roller bearings are excluded because they have a rolling resistance that is too high for this application. Ball bearings are used, but they have various shortcomings. Examples of these defects include: the eccentricity, taper and lack of roundness of the races of the ball bearings; the asymmetry of the raceways in the ball bearing rings with respect to the plane of symmetry normal to the roll axis; the inclined position of the roll axis in relation to the direction of movement, which means that certain forces are not in the plane of symmetry and therefore the connecting line between the point of contact of a ball with an outer race and the point of contact of a ball with an inner race is not in the plane of symmetry . When the rolling direction is reversed, this straight line tilts into the position symmetrical with respect to the plane of symmetry, because the balls change into their other equilibrium position.

Inaccuracies can also be attributed to the guideway. Apart from the deformations of the stator that are passed on by the guideway, the surface of the guideway has other causes of inaccuracies in that local variations in its surface condition can change the behavior of the ball bearings. A conventional partial solution to the guiding problem is that the ball bearings are specifically selected and individually adjusted on the height measuring gauge by means of the deformations which are brought about, which is associated with a very high outlay.

It is therefore the object of the invention to provide a height measuring gauge which achieves the required accuracy more reliably and with a far lower expenditure on material, construction and adjustment than with the conventional height measuring gauges. According to the invention, this object is achieved by the combination of features specified in claim 1. Advantageous designs of the height measuring gauge according to the invention result from the dependent patent claims.

Thanks to this combination of features, the advantages listed below result, among other things, from the height measuring gauge according to the invention.

The special base of the height gauge has a large area and has a flat contact surface with the reference plane of the measuring table. This contact surface is relieved by the air pressure, ie the air pressure transfers the weight of the height measuring gauge to the entire surface of the measuring table, which is encompassed by the extent of the depression in the base. This results in a lower pressure exerted by the base on the measuring table at each point of contact, the material of the base and the measuring table is correspondingly relieved and less deformed. However, the base does not float on an air cushion, so that the support remains free of canting, and nevertheless, thanks to the relief, the sliding properties of the base on the measuring table are almost as good as with an air cushion. As a result, the self-lapping remains low; in the course of using the height measuring gauge, there is no noticeable deterioration in the perpendicularity of the measuring path to the reference plane. The amount of air required for this is small since it is not intended to form an air cushion, and therefore only a small amount of air escapes between the non-ideal contact surfaces of the base and the measuring table. Finally, since the support is not based on the tripod principle, the heating of the base due to the power loss on a transformer does not have a significant effect on the accuracy, so that the evaluation electronics together with its supply transformer can be easily integrated in the vicinity of the base of the height gauge , For example, by arranging them in the handle, which can be thermally decoupled from the base as a precaution.

The special double mounting of the column in the stand ensures that the forces acting on the column are always symmetrical to the longitudinal axis of the column, regardless of an adjustment of the column in relation to the base of the height gauge. Apart from the forces exerted by the sled, essentially only gravity acts on the column. In particular, the sliding fit in the upper bearing allows the column to expand freely. Thus, there are no tensions on the column which could impair the necessary quality of the column geometry achieved during manufacture, since these tensions would tend to be reduced by deformations over time. The perpendicularity of the column to the reference plane can also be adjusted independently of the base of the height gauge thanks to the upper sliding seat which can be adjusted parallel to the reference plane.

The special upper bearing of the column exerts only insignificant forces on the stand, which arise in maintaining the unstable balance of the column and lie in a plane normal to the longitudinal axis of the stand. This bearing therefore does not generate any torque on the stand. Otherwise, the stand is constructed symmetrically. Apart from the fastening screws which are screwed in from the base and from above, but which are arranged axially symmetrically, there are no elements which generate stresses during assembly which occur in the Would be degraded over time by deformation. The tension of the steel strip, which creates the connection with the counterweights, is also transmitted in exactly one of the planes of symmetry via the deflection rollers and their roller bearings on the top and bottom of the stand, so that this stress is also symmetrical.

The special adjustment possibility of each ball bearing axis allows the respective axis to be set relative to the running surface in such a way that the taper of the outer surface of the outer race is compensated for. This adjustment option also allows the respective axis to be aligned such that all the forces come to lie in the plane of symmetry, which also means that the points of contact between the balls and the running surfaces touching them also come to lie in this plane of symmetry. Thanks to the excellent adjustment of the slide's ball bearings, the tension of the steel band and the mass of the counterweights attached to them can be lower than with conventional height gauges, which in turn helps to keep the stand's load low.

Finally, the preceding combination of features and advantages makes it possible to use a guideway in which only two surfaces lying at right angles to one another fulfill a guiding task and can be brought closer to a geometrically ideal plane by fine machining. The other, in each case parallel counter-pressure surfaces merely form the support of those races which, with a sufficient elastic reserve, support the bearing force, i.e. must produce the pressure of the opposite races on the guide surfaces.

Preferred configurations and further advantages of the height measuring gauge according to the invention result from the following description and from the attached drawings. Show it: 1 is an exploded view of part of the inventive height gauge in the vicinity of the base, partly with parts shown transparently,

2 is a partially broken perspective drawing of part of the inventive height gauge in the vicinity of the slide, partly with parts shown transparently,

3 shows a perspective drawing of a part of the height measuring gauge according to the invention in the vicinity of the counterweight of the slide, partly with parts shown in a transparent manner,

4 shows a perspective drawing of a part of the height measuring gauge according to the invention in the vicinity of the upper part of the height measuring gauge, partly with parts shown in a transparent manner,

5 shows a side view of the base of the height measuring gauge according to the invention, in a vertical axial section,

6a is a side view of a lockable ball bearing support of the height measuring gauge according to the invention, partly in a vertical axial section,

6b is a plan view of the same ball bearing carrier as in Fig. 6a,

7a is a side view of an elastically pressed

Ball bearing carrier of the height measuring gauge according to the invention, partly in a vertical axial section,

7b is a plan view of the same ball bearing carrier as in Fig. 7a, 8 is a side view of a fastening system or a pressing system for the ball bearing supports of the height measuring gauge according to the invention, partly in a vertical axial section.

In FIGS. 1 to 8, parts of the height measuring gauge, which occur several times with the same design, are identified by the same reference numerals. In the following, these reference numerals are retained every time, even if a designated part cannot be seen in the figure just described, for example because it is covered because of the perspective view.

In Fig. 1, a base 1 of the height measuring gauge is shown, which is intended to lie on the horizontal surface of a measuring table and to be easily displaceable thereon in the horizontal direction. This horizontal surface of the measuring table therefore coincides with the lower surface of the "base 1, which forms a flat support surface 2 for supporting the height measuring gauge on the measuring table and at the same time a reference plane of the height measuring gauge to the measuring table. On the base 1 there is a vertical guideway 3 is supported for a slide 4 (FIG. 2) on which a button 5 can be fastened, and a vertical guide track 6 for a counterweight 7 (FIG. 3) is also supported on the base 1. The counterweight 7 is at a fastening point 8 is connected to the carriage 4 by a band 9 and 10 for train and counter-train 10. The band for train 9 runs up from the counterweight 7, via a horizontal deflection roller 11 (FIG. 4), which is in the vicinity of the upper part of the height gauge is arranged, and from there down to the carriage 4, to which it is connected at an attachment point that is not visible in the perspective view m counterweight 7 down, over a horizontal-axis deflection roller 12 (Fig. 1), which is arranged in the vicinity of the base 1 of the height measuring gauge, and from there up to the slide 4, with which it is attached to the same in the Spective view not visible attachment point is connected as the band for train 9.

The base 1 is essentially symmetrical about a vertical axis of symmetry 13 (FIG. 5). On its underside 2, which coincides with the reference plane and serves as a support surface, it has a depression 14, the circumference of which is designated by 15 in the reference plane 2. The outer circumference of the contact surface 2 is designated 16. Thus, the support surface 2 i is essentially symmetrical about the vertical axis of symmetry 13, and it lies between the circumference 15 of the depression 14 and the outer circumference 16 of the support surface 2. For example, the circumference 15 of the depression 14 is circular and the circumference 16 of the support surface 2 is essentially quadrangular (possibly with rounded or beveled corners), the dimensions being selected such that the projection of the depression 14 onto the support surface 2 covers an area which is 30 to "50% of the inside the circumference 16 of the total base area of the base 1.

Through the base 1 lead on the one hand an air inlet duct 17 from a connection for compressed air (not shown) to the depression 14 and on the other hand an air outlet duct 18 from the depression 14 to a pressure regulating device which is designed as a nozzle 19 and causes an overpressure in the depression 14, when compressed air is supplied via the air inlet duct 17.

On the base 1, a vertical stand 20 is supported, which is designed as a vertically aligned double-T profile. The flanges of the double-T profile are supported and fastened to the base, for example by screws (not shown) which are screwed into the flanges from below and through base 1. This stand 20 is near its upper end (Fig. 4) with a support member 21 provided, which is advantageously formed substantially as a plate and is supported and fastened to the flanges of the double-T profile, for example by screws (not shown) which are screwed into the flanges from above and through the carrier part 21 become. Two columns 22 and 23 lead from the base 1 to the carrier part 21, both of which are designed in the form of a square profile and are arranged such that the web of the double-T profile lies between the two columns 22 and 23. A holder 24 for the upper end of the column 22 and a holder 25 for the upper end of the column 23 are arranged in the carrier part 21. The brackets 24 and 25 are releasably attached to the carrier part 21, the holder 24 by means of screws, not shown, which are guided through the holes 26 in the holder 24 and the holes 27 in the carrier part 21, the holder 25 by means of screws 28, which are horizontal are guided through the carrier part 21. In the released state of their attachment, the brackets 24 and 25 are on the carrier part by displacement in a horizontal plane

21 adjustable to allow vertical alignment of the columns 22 and 23. In the example shown, the holder 24 is translationally displaceable, while the holder 25 is set according to the principle of the rotatable eccentric. With the screws mentioned, the brackets 24 and 25 and thus the columns 22 and 23 can be locked in the set position.

The brackets 24 and 25 are as plain bearings for the columns

22 and 23 and allow displacement of the respective column in the vertical direction without allowing play of the column in the horizontal direction. For example, a bolt 29 is axially screwed into the bore 30 of the column 22 for this purpose. This bolt 29 is axially sliding through the bore 31 of the bracket 24 but without play. To make this device easier to manufacture, in particular to make it easier to choose the right materials, the bolt 29 is inserted into the bore of a sleeve 32 without play slidably guided, and this sleeve 32 is fixed in the bracket 24. The column 23 is fastened, for example, in a similar manner, not shown, in the holder 25 without play.

At its lower end (FIG. 1), the column 22 is supported on the base 1 via a joint 33 of the ball-socket type. For this purpose, a recess 35 in the form of a hollow cone is arranged at the lower end of the column 22. A recess 36 (FIG. 5) in the form of a vertical-axis hollow cone is arranged on the base coaxially to the longitudinal axis of the column 22. Between the recess 35 and the recess 36, a ball 37 is arranged which touches the outer surface of one and the other hollow cone 35 and 36 along a circle.

In order to eliminate any play at this joint 33, the ball 37 is provided with an axial bore. A bolt 34 is axially screwed into the lower end of the column 22 and is passed through the axial bore of the ball 37 essentially without contact. On the lower end of the bolt 34, an elastic element 38, for example a ^" spiral spring", and a screw nut 39 are arranged such that the column 22 is pulled against the base 1 with moderate force and thus the joint 33 is always under moderate pressure remains.

It is of course possible to also support the column 23 on the base via a similar ball-socket type joint.

The column 22 serves as a vertical guideway 3 for the slide 4, while the column 23 serves as a vertical guideway 6 for the counterweight 7. In other words, the slide 4 runs along the column 22, while the counterweight 7 runs along the column 23. Of the four side surfaces of the column 22 for the slide 4, however, only two side surfaces that are adjacent to one another need to be designed as guide surfaces of the highest possible accuracy. The two other side surfaces, which are also adjacent to one another, can be designed as merely flat counter pressure surfaces if the measures specified below are taken in order to maintain the accuracy.

The web of the double-T profile has a recess in the vicinity of the base 1 and in the vicinity of the support part 21, which enables the deflection roller 11 to be arranged on the support part 21 and the deflection roller 12 on the base 1. The axes of the deflection rollers 11 and 12 lie essentially in the extension of the web of the double-T profile, so that the web lies between the two vertical parts of the band for train 9 and the band for counter train 10.

Races 40 (FIG. 2) are arranged in the vicinity of the upper and lower ends of the slide 4 and roll on the respective corresponding side surface of the column 22. The running rings 40 are over one. respective ball bearings 41 are supported on respective ball bearing supports 42 and 43, which in turn are supported on the slide 4.

As will be described below, at least the ball bearing supports 42 for those races 40 which roll on one of the guide surfaces can be adjusted relative to the slide 4 in the rolling, pitching and rolling directions and can be locked in the set position. All relevant ball bearing supports 42, ie the ball bearing supports 42 for all race rings 40 which roll on the column 22 on one of the guide surfaces, can be mounted in this way. If, however, these guide surfaces are arranged such that one of them, namely the guide surface 44 in FIG. 2, faces the button 5, it is possible and inexpensive to place those races 40 which roll on this guide surface 44 facing the button 5 on one to mount on the slide 4 firmly supported ball bearing carrier, which simplifies the ball bearing carrier in question except for one axis of the ball bearing in question. How likewise described below, the ball bearing supports 43 for those races 40 which roll on a counter pressure surface are arranged on the slide 4 such that they can move in the rolling, pitching and rolling directions and are elastically loaded towards the relevant counter pressure surface. This gives the possibility of positioning and then locking the races 40 rolling on one of the guide surfaces as required, while the races 40 rolling on the counter pressure surfaces set themselves automatically and freely as required, which is based on three Side surfaces of the column 22 ensure an adjustment of the races 40 and (as mentioned above) allows to dispense with an adjustment possibility for the races 40 rolling on the fourth side surface of the column 22, although this side surface is a guide surface.

6a and 6b, a ball bearing carrier 42 is shown for a race 40 rolling on a guide surface. This ball bearing carrier 42 is intended and designed to be set on the carriage 4 in the rolling and pitching directions according to the tripod principle. For this purpose, an adjusting screw (not shown) can be screwed into one of the threaded bores 45, 46, 47 of the ball bearing carrier 42 (also visible in FIG. 2). The tips of these adjusting screws rest on the slide 4. The ball bearing carrier 42 is also designed and designed to be adjusted on the carriage 4 in the direction of the roll. For this purpose, an adjusting screw (not shown) can be screwed into a threaded bore 48 (also visible in FIG. 2) of the ball bearing carrier 42. The tip of this adjusting screw also lies on the slide 4. To adjust this adjusting screw, its head is accessible through a bore 58 (FIG. 2) in the carriage 4 for a screwdriver. A fastening screw 49 (FIG. 8) is through a bore 50 for fastening the ball bearing carrier 42 to the carriage 4 of the ball bearing carrier 42 and inserted into the slide 4 screwed, the diameter of the bore 50 is larger than the diameter of the fastening screw 49. In this way, this fastening screw 49 can serve as an axis for rotation of the ball bearing carrier 42 on the carriage 4 and thanks to the play provided between the bore 50 and the fastening screw 49 also adjustment of the ball bearing carrier 42 on the slide 4 in the rolling and pitching direction is permitted.

In the ball bearing carrier 42, the seat of the head 51 of the fastening screw 49 is formed as a conically shaped bore 52. Between this seat or the conically shaped bore 52 and the head 51 of the fastening screw 49, a washer 53 designed as a hemisphere is arranged, which is placed on the fastening screw 49 such that the hemisphere faces and is adjacent to the conical bore 52. In a simpler embodiment, the head 51 of the fastening screw 49 could be designed as a hemisphere facing the conical bore 52. In another variant, the fastening screw 49 can be used in an inverted position, the head of the fastening screw 49 lies in the carriage 4, while a screw nut is screwed onto the body of the fastening screw 49 after the washer 53. Again, in a simpler embodiment, the screw nut could be formed directly as a hemisphere facing the conical bore 52. It can also facilitate the construction and assembly of this fastening means for the ball bearing carrier 42 if a washer 54 is inserted between the flat side of the washer 53 designed as a hemisphere and the head 51 or the nut of the fastening screw 49, which serves only as a spacer and is designed as a cylinder with mutually parallel end faces.

On the ball bearing carrier 42 there is also a bore 55 for receiving and holding the (not shown) axis of the ball bearing 41 provided for the race 40. So that the race 40 rolls on the guide surface, this bore 55 and its axis are arranged parallel to the guide surface.

The axes of the three threaded bores 45, 46, 47 of the ball bearing carrier 42 (and thus also the axes of the adjusting screws inserted therein) are parallel to one another, to the axis of the bore 55 (and thus also to the axis of the race 40 and to the relevant one Guide surface on which the race 40 rolls) is arranged orthogonally and symmetrically to the plane of symmetry 66 of the race 40.

The axes of the threaded bores 45, 46 (and thus also the axes of the adjusting screws inserted therein) intersect the axis of the bore 55 (and thus also the axis of the race 40) at right angles, and they are symmetrical to the plane of symmetry 56 of the race 40 arranged. The axis of the threaded bore 47 (and thus also the axis of the adjusting screw inserted therein) is arranged in the plane of symmetry 56 of the race. These axes of the three adjusting screws are thus arranged in the projection plane of FIG. 6b at the corner points of an isosceles triangle. The axis of the fastening screw 49 lies parallel to the axes of the threaded bores 45, 46-, 47 and therefore also to the axes of the three adjusting screws. This axis of the fastening screw 49 intersects the projection plane of FIG. 6b essentially in the center 57 of the (not shown) circumference of the isosceles triangle corresponding to the axes of the threaded bores 45, 46, 47, i.e. it lies at the same distance from each of the three other axes in the plane of symmetry 56 of the race 40.

The axis of the threaded bore 48 (and thus also the axis of the adjusting screw used therein) is arranged parallel to the guide surface and normal to the plane of symmetry 56, that is to say it lies parallel to the projection plane of FIG. 6b and Axis of the bore 55 (and thus also to the axis of the race 40). This axis of the threaded bore 48 is closer to the center 57 than the axis of the threaded bore 47, ie this axis of the threaded bore 48 intersects the plane of symmetry 56 between the center 57 and the corner point of the isosceles triangle lying on the plane of symmetry 56, where the axis of the threaded bore 47 lies.

A threaded bore 59, which is essentially parallel to the threaded bore 48, is arranged on the slide, into which a counter screw (not shown) is screwed, the tip of which bears against the ball bearing carrier 42. Tightening this counter screw acts counter to tightening the screw in the thread. hole 48 inserted adjusting screw.

If the fastening screw 49 is now loosened, thanks to the ball-socket-gel.enk formed by the washer 53 in the conical bore 52, the tilting of the ball bearing carrier 42 by adjusting the adjusting screws in the threaded holes 45, 46, 47 and the rotation of the Ball bearing support 42 by adjusting the adjusting screw and the counter screw in the threaded bores 48 and 59. When the fastening screw 49 is tightened slightly, the adjusting screws seated in the threaded bores 45, 46, 47 are pressed against the slide 4, so that the position tion of the ball bearing carrier 42 is firmly defined and locked according to the tripod principle. It may be advantageous to design the washer as an elastic element, for example in the form of a rubber cylinder or a package of spring washers, in order to use an elastic force or a spring force instead of a metered tightening torque of the fastening screw 49 (both cases are analogous, in that way or so an elastic load is generated and converted into force).

7a and 7b, a ball bearing carrier 43 is on a counter pressure surface rolling race 40 shown. This ball bearing carrier 43 is intended and designed to be set on the carriage 4 in the rolling and pitching directions according to the tripod principle. For this purpose, an adjusting screw (not shown) can be screwed into one of the threaded bores 60, 61 of the ball bearing carrier 43. The tips of these adjusting screws rest on the slide 4. The race acts here as the third leg, as will be explained in the following. In addition, a pressure screw 49 (FIG. 8) can be passed through a bore 62 of the ball bearing carrier 43 and screwed into the slide 4, the diameter of the bore 62 being larger than the diameter of the fastening screw 49 ¬ se pressure screw 49 serve as an axis for a rotation of the ball bearing carrier 43 on the slide 4 and, thanks to the play provided between the bore 62 and the pressure screw 49, also allow the ball bearing carrier 43 on the slide 4 to be adjusted in the rolling and pitching directions.

The ball bearing carrier 43 is also designed and designed to be set on the slide 4 in the direction of the roll. For this purpose, an adjusting screw (not shown) can be screwed into a threaded bore 63 of the ball bearing carrier 43. The tip of this adjusting screw also lies on the slide 4. To adjust this adjusting screw, its head is accessible to a screwdriver through a bore 58 in the slide 4.

In the ball bearing carrier 43, the seat of the head 51 of the pressure screw 49 is designed as a conically shaped bore 64. Between this seat or the conically shaped bore 64 and the head 51 of the fastening screw 49 there is a washer 53 designed as a hemisphere, which is placed on the pressure screw 49 such that the hemisphere faces the conical bore 64 and is adjacent. Between the head 51 of the pressure screw 49 and the plane On the side of the washer 53, which is designed as a hemisphere, an element 54 is inserted, which is elastic at least in the axial direction and is designed as a cylinder with mutually parallel end faces. For example, this element 54 can be designed in the form of a rubber cylinder or a package of spring washers. The axially directed elastic force of the elastic member 54 acts between the head 51 of the Anpressschraube 49 and the ball bearing support 43 in such a direction that the ball bearing support 43 and thus also of the race 40 is pressed to ^{'counter-pressure} surface. In a variant, the pressure screw 49 can be used in an inverted position, the head of the pressure screw 49 lies in the slide 4, while a screw nut is screwed onto the body of the pressure screw 49 after the washer 53 and the elastic element 54.

On the ball bearing carrier 43 there is also a bore 65 for receiving and holding the (not shown) axis of the ball bearing 41 for the race 40. So that the race 40 rolls on the counter pressure surface, this bore 65 and its axis are arranged parallel to the counter pressure surface.

The axes of the threaded bores 60, 61 of the ball bearing carrier 43 (and thus also the axes of the adjusting screws used therein) are parallel to one another, to the axis of the bore 65 (and thus also to the axis of the race 40, as well as to the relevant counter pressure surface on which the Race 40 rolls) orthogonally, and arranged symmetrically to the plane of symmetry 66 of the race 40. These axes of the two adjusting screws are thus arranged in the projection plane of FIG. 7b at the corner points of the base of an isosceles triangle, the third corner point of which is the orthogonal projection 67 of the center of the race 40 on the same projection plane of FIG. 7b is. The axis of the pressure screw 49 lies parallel to the axes of the threaded bores 60, 61 and therefore also to the axes of the two adjusting screws. This 7b essentially intersects the axis of the pressure screw 49 in FIG. 7b in the center 68 of the (not shown) circumference of the isosceles triangle corresponding to the axes of the threaded bores 60, 61 and the orthogonal projection 67 of the center of the race 40, ie it lies in the plane of symmetry 66 of the race 40 at the same distance from the two other axes and to the center of the contact point of the race 40 with the counter pressure surface (whose projection onto the projection plane of FIG. 7 b yes coincides with the projection 67 of the center of the race 40).

The axis of the threaded bore 63 (and thus also the axis of the adjusting screw used therein) is arranged parallel to the counter pressure surface and normal to the plane of symmetry 66, i.e. it lies parallel to the projection plane of FIG. 6b and to the axis of the bore 65 (and thus also to the axis of the Race 40). This axis of the threaded hole 63 is closer to the center 68 than the axes of the threaded holes 60 and 61, i. H. this axis of the threaded bore 63 intersects the plane of symmetry 66 between the center 68 and the corner points of the base of the isosceles triangle lying on the plane of symmetry 66, the third corner point of which projects the projection 67 of the center of the race 40 on the same projection plane of FIG 7b is.

A threaded bore 59, which is essentially parallel to the threaded bore 63 and into which a counter screw (not shown) is screwed, the tip of which bears against the ball bearing carrier 43, is arranged on the slide. Tightening this counter screw acts counter to tightening the adjusting screw inserted in the threaded bore 63.

Thanks to the ball-socket joint formed by the washer 53 in the conical bore 64 in combination with the elasticity of the elastic element 54, the pressure screw 49 allows the ball bearing carrier 43 to be tilted by adjusting the adjusting screws in the threaded bores 60, 61 and the rotation of the ball bearing carrier 43 by adjusting the adjusting screw and the counter screw in the threaded bores 63 and 59. The system behaves as if the contact screw 49 were always a slightly tightened fastening screw . The adjusting screws seated in the threaded bores 60, 61 are pressed against the slide 4 and the race 40 against the counter pressure surface, so that the position of the ball bearing carrier 42 according to the tripod principle is fixed and also the opposite race arranged on the ball bearing carrier 42 40 is constantly tightened or pressed against its corresponding guide surface.

Claims

1. Height gauge with

a base (1) which has a flat bearing surface (2) in a reference plane for support on the horizontal surface of a measuring table,

- a vertical guideway (3) for a carriage (4) on which a button (5) can be attached,

a vertical guideway (6) for a counterweight (7), which is connected to the carriage (4) by a belt (9, 10) running for a deflection roller (11, 12) for pull and pull,

- a vertical stand (20) supported on the base (1) for holding (24, 25) the two aforementioned guideways (3, 6),

characterized by the combination of the following features:

the base (1) is essentially symmetrical about a vertical axis of symmetry (13) and has a depression (14) on its underside, the circumference (15) of which in the reference plane defines an inner circumference of the support surface (2), which is at a distance from an outer circumference (16) of the support surface (2) in the reference plane, so that the support surface (2) is essentially symmetrical about a vertical axis of symmetry (13) and between the inner and the outer circumference ( 15.16);

- through the base (1) lead on the one hand an air inlet channel (17) from a connection for compressed air to the depression (14) and on the other hand an air outlet channel (18) from the depression (14) to a pressure regulating device (19); - The two guideways (3,6) are each formed as a column (22,23) in the form of a square profile;

- The stand (20) is provided in the vicinity of its upper end with a support part (21) in which a holder (24, 25) for each upper end of one of the columns (22, 23) is detachably fastened, wherein these brackets (24, 25) for vertical alignment of the columns (22, 23) can be adjusted by shifting in a horizontal plane on the support part (21) and can be locked in the set position,

- The brackets (24, 25) are designed as slide bearings for the columns (22, 23) and allow the respective column (22, 23) to be displaced in the vertical direction without allowing play in the horizontal direction;

- At least one column (22) for the carriage (4) is supported at its lower end via a joint (33) of the ball-socket type on the base (1);

- In the vicinity of the upper and lower ends of the slide (4-), races (40) for rolling are arranged on each side surface of the column (22) and are supported by ball bearings (41) on ball bearing supports (42, 43) which are in turn supported on the slide (4);

- Of the four side surfaces of the column (22) for the slide (4), two adjacent side surfaces are designed as guide surfaces (44) of the highest possible accuracy and the other two, also adjacent side surfaces.

- At least the ball bearing supports (42) for those races (40) that roll on one of the guide surfaces can be adjusted relative to the slide (4) in the rolling, pitching and rolling directions and locked in the set position. bar ; and

- The ball bearing carrier (43) for those races (40) that roll on counter pressure surfaces are movably arranged on the slide (4) in the rolling, pitch and roll directions and are elastically loaded towards the counter pressure surface in question.

2. Height gauge according to claim 1, characterized by the combination of the following features:

- at least the ball bearing support (42) for those Lauf¬ rings (40) which roll on one of the guide surfaces, are on the carriage (4) for setting in roll and pitch direction of the three-legged design with three threaded holes (45, ^'46 , 47) of the respective ball bearing bracket (42) screwed in tripod adjusting screws, the tips of which rest against the slide (4), and for adjustment in the winder direction with a single adjusting screw screwed into a threaded bore (48) of the ball bearing bracket (42), the tip of which on the slide ( 4) rests, is supported and can be locked in the set position by a fastening screw (49) screwed into the slide (4), whereby

- the axes of three tripod-threaded bores (45,46,47) are arranged parallel and orthogonal the surface to Führungsflä¬ of each other, the axes of ^'two die¬ ser threaded bores (45,46), the axis of the raceway (40) cut at right angles and are arranged symmetrically to the plane of symmetry (56) of the race (40), and the axis of the third threaded bore (47) is arranged in the plane of symmetry (56) of the race (40), such that the Intersect axes of the three threaded bores (45, 46, 47) a perpendicular projection plane at the corner points of an isosceles triangle,

- The axis of the fastening screw (49) parallel to the axes of the three tripod threaded bores (45, 46, 47) and in the plane of symmetry (56) of the race (40) and essentially in the center (57) of the circumference of the isosceles triangle,

- The axis of the threaded bore (48) of the individual adjusting screw is arranged parallel to the guide surface and normal to the plane of symmetry (56) of the race (40), such that this axis is the plane of symmetry (56) of the race (40) between the Intersects the center (57) of the circumference of the isosceles triangle and the corner point of the isosceles triangle lying on the plane of symmetry (56) of the race (40),

the fastening screw (49) serves as an axis for the rotation of the ball bearing carrier (42) when the individual adjusting screw is set in its threaded bore (48),

- And on the slide (4) in a threaded bore (59) essentially parallel to the threaded bore (48) of the individual adjusting screw (59) there is a counter screw acting on the ball bearing carrier (42) against this single adjusting screw, the tip of which on the ball bearing carrier ( 42) is present

- And the ball bearing carrier (43) for those races (40) that roll on counter pressure surfaces are on the slide (4) for setting in the rolling and pitching direction according to the tripod principle with two threaded holes (60, 61) each ¬ three-leg adjustment screws, the tips of which rest against the slide (4), and a pressure screw (49) and for adjustment in the winder direction with a single screwed into a threaded bore (63) of the ball bearing bracket (43) Adjusting screw, the tip of which rests on the slide (4), supported - The axes of the pressure screw (49) and the tripod threaded holes (60, 61) are arranged parallel to one another and orthogonal to the counter pressure surface,

- The axes of the three-leg threaded bores (60, 61) are arranged orthogonally to the axis of the race (40) and symmetrically to the plane of symmetry (66) of the race and intersect a projection plane perpendicular thereto at two corner points of an isosceles triangle, the third corner point is the orthogonal projection (67) of the center of the race (40) on the same projection plane,

- The axis of the pressure screw (49) parallel to the axes of the two tripod threaded holes (60,61) and in the plane of symmetry (66) of the race (40) and essentially in the center (68) of the circumference of the isosceles Triangle is arranged, and this pressure screw (49) is screwed into the carriage (4), while between its head (51) and the ball bearing carrier (43) an elastic force acts in such a direction that the ball bearing carrier (43) and so that the race (40) is pressed towards the counter pressure surface,

- The axis of the threaded bore (63) of the individual adjusting screw is arranged parallel to the counter pressure surface and normal to the plane of symmetry (66) of the race (40) such that this axis is the plane of symmetry (66) of the race (40) between the Intersects the center (68) of the circumference of the isosceles triangle and the base of the isosceles triangle which is normal to the plane of symmetry (66) of the race (40),

the contact screw (49) serves as an axis for the rotation of the ball bearing carrier (43) when the individual adjusting screw is set in its threaded bore (63), - And on the slide (4) in a threaded bore (59) which is essentially parallel to the threaded bore (63) of the individual adjusting screw, a counter screw acting on the ball bearing carrier (43) against this single adjusting screw is arranged, the tip of which on the ball bearing carrier ( 43) is present.

3. Height gauge according to claim 2, characterized in that the seat of the head (51) of the fastening screw (49) in the ball bearing carrier (42) for a race (40) which rolls on a guide surface as a conically shaped bore (52) and Head (51) of the fastening screw (49) is designed as a hemisphere facing the conical bore (52).

4. Height gauge according to claim 2, characterized in that the seat of the head (51) of the fastening screw (49) in the ball bearing carrier (42) for a race (40) which rolls on a guide surface, formed as a conically shaped bore (52) and A washer (53) designed as a hemisphere is arranged between this seat and the head (51) of the fastening screw (49), the hemisphere facing and adjacent to the conical bore (52).

5. Height gauge according to claim 2, characterized in that the seat of the head (51) of the pressure screw (49), which serves as an axis for the rotation of a ball bearing carrier (43) for a race (40) that rolls on a counter pressure surface, as conical bore (64) is formed and between this seat and the head (51) of the pressure screw (49) there is an elastic element (54) and a washer (53) designed as a hemisphere, the hemisphere of the conical bore ( 64) faces and is adjacent.

6. Height measuring gauge according to claim 1, characterized in that the joint (33) for supporting the column (22) for the Carriage (4) on the base (1) has a recess (35) arranged coaxially to the longitudinal axis of the column (22) in the form of a hollow cone, a recess (36) arranged in the base (1) in the form of a vertical-axis hollow cone and a ball ( 37), the ball (37) touching the lateral surface of one and the other hollow cone (35, 36) along a circle.

7. Height gauge according to claim 1, characterized in that the stand (20) is designed as a vertically oriented double T profile.

8. Height gauge according to claim 7, characterized in that the flanges of the double-T profile are supported and fastened at one end of the stand (20) on the base (I), the carrier part (21) for the brackets (24, 25) of the columns (22,23) is substantially formed as a plate and filtered off in the vicinity of the other end of the stand (20) supports on the flanges and is fastened, and the web of the double T-profile ^"between the two _j columns ( 22,23) is arranged.

9. Height gauge according to claim 8, characterized in that the web of the double-T profile in the vicinity of the base (1) and in the vicinity of the support part (21) each has a recess, and on the base (1) and on the support part (21 ) a deflection roller (11, 12) is arranged for each of the belts (9, 10), the axes of the deflection rollers (11, 12) lying horizontally and essentially in the extension of the web, so that the web between the two vertical parts of each band (9, 10).

10. Height measuring gauge according to claim 1, characterized in that the projection of the depression (14) on the bearing surface (2) is 30 to 50% of the total base area.

11. Height gauge according to claim 1, characterized in that the pressure regulating device (19) is a nozzle which in the depression (14) causes excess pressure.