DE2237570A1 - DEVICE FOR MECHANICAL REGISTRATION OF DEFORMING MOVEMENTS - Google Patents

Description

PAIUMTANWÄLTE

HELMUT SCHROETER KLAUS LEi-IMANN DIPL.-fHYS. DIPL.-ING. 8 MONCHEiN 525 - LIPOWSKYSTR. 30 _:

jx-te-11 31.7.72t

Technology Incorporated

Apparatus yarn mechanical registration of deformation movements

With "certain" known devices for the mechanical recording of the deformation movements that a component executes under the effect of changing loads, z. B. in the U, S, A. Patents 2 Oöl 579 and 3 430 250 described, a round, disk-like registration plate is rotatably supported by a round plate, which is attached to a surface of the component to be monitored or tested · There is also a stylus or pen present that is in contact with the top of the registration plate is held by an arm which extends from another base plate, which also is attached to the component to be monitored or tested · Every relative movement of the two base plates is caused a radial movement of the stylus with respect to the registration plate, and while si oh. advancing the registration plate

turns, it is provided with a mark by the graver, each corresponding to each deformation caused by changes the stress on the component or due to thermal expansion or contraction of the component is"

It has been found useful to ensure that the registration plate is compulsory and accurate is moved further if it is provided with incised marks «When this happens, the incised marks, the helative movements clearly distinguish between sections of the component to which the device is attached the. Thus it is possible to reduce the compressive stresses or contraction movements clearly distinguish the scratch marks representing the component from other scratch marks, the tensile stresses or expansion movements of the component represent.

In the device of the U.S.A. patent

2 Oöl 579 is the registration plate by a clock spring twisted torsion spring resembling that on the Heglstrier plate constantly applies a torque and a rotary motion brings about the registration plate when the stylus moves radially with respect to the registration plate. The usage Such a torsion spring for the stated purpose, however, leads to uncontrollable movements of the registering plate, and if the stylus is set in vibrations or is lifted off the registration plate, the torsion spring runs off and rotates the registration plate in an uncontrolled manner, so that the device is then no longer operational is.

In the device of the U.S.A. patent

3 430 250, the registration plate is only rotated further if the component to be monitored is compressed or contracts. As a result, radial scratch marks are created

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only produced when the component is subjected to tensile stress or when it has expanded sometimes is difficult ₉ asu distinguish the Hitzmarken ·

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Furthermore, it has proven to be appropriate, measures

have been meeting, which allowed ,, set up a Hegistrierplatte on fc »tjueme way to the device and the Begia $ also rierplatte to" convenient way to refer _s demand ϋ & Ά recorded on it information on the Beans Prato Hungen of components _e Furthermore, it has been found desirable ,, measures to tref £ ₉ en it ermSglichen, atoeudecken the Eegistrierpiatte after their incorporation into die'Vorriöhtung to, they mnd against interfering minor impacts / or water, dust and other foreign matter in the ümgetoungsluft% u · protect

The device for registering stresses can, for example, be attached to a moving component, for example on a wing of an airplane or a fiotorflügel of a helicopter, around the on the To register the stresses attributable to deflection * It is also possible for the device 5m to be stationary Object, e.g. B. to be attached to a bridge or a building During use, the recorder can be exposed to extreme weather conditions and / or rapid ! Be exposed to currents of air that carry foreign bodies with them · The device can also have significant temperature changes be exposed to cause the corresponding thermal expansion or contraction movements of the device » It is important that such air currents or thermal expansion and contraction movements be accurate

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Do not influence the work of the registration device or falsify the registration of claims

The invention is based on the object of an improved to provide mechanical device for registering stresses which are desirable as mentioned above Has features and is in particular designed so that the registration plate inevitably and accurately in a certain Direction is moved or rotated further depending on the fact that the stylus is opposite the registration plate moves in one direction or another to move all heat marks including those which are extremely small Represent deformations, clearly differentiate them and have them evaluated. Furthermore, the inventive Hegistriervorrichtung designed so that the registration plate conveniently insert and can see that the registration plate is protected after insertion into the device is, and that an accurate registration of information about stresses is guaranteed even with significant temperature changes is «Furthermore, according to the invention, an improved registration plate has been created that not only Can be produced at low cost, but also conveniently and quickly with the help of an optical reading device can be evaluated.

In one embodiment of the invention is a flat one annular registration plate on a truncated cone Rotatable knob which engages in an opening in the center of the registration plate and is part of a thin one flexible leaf spring forms. A burin is mounted under the registration plate by means of another thin flexible spring, which is rigidly connected to a rear or second base plate. The registration plate is on the one carrying it Button temporarily held by a resilient retaining part made of wire, which is arranged on the first base plate

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Guides are held in place.

The holding part is also used to insert a protective cover to hold their closed position, in which the is parallel to the base plates over the registration plate away extends · The protective cover is pivotably connected to the second base plate and can be brought into an open position to enable the insertion or removal of a registration plate. The protective cover carries a Set of spring actuator locators that cooperate with the top of the registration plate when the protective cover is pivoted into its closed position. These resilient actuating fingers work together with the radially extending upper side of the registration plate and inevitably cause a step-by-step rotation of the registration plate in from -... dependence of relative movements between the base plates, which are attached to the component, with regard to its stress to be monitored or checked.

In another embodiment of the invention, strips of an elastic foam material are between the Protective cover and the base plates arranged to form an outwardly sealed enclosure for the registration plate form, and the registration plate against dust, water and others Protect foreign matter as soon as the protective cover has been set in its closed position. At. another Embodiment, the registration plate can consist of a clear, consist of transparent plastic and have a colored surface that can be penetrated by the burin. if the Eitz marks generated on the registration plate are evaluated light is directed in axial direction onto the registration plate, and the light penetrating through the Eitzmarks is then in a strong contrast to the light falling through the other parts of the registration plate, so that the Eitz marks can be easily detected with the help of an optical analyzer.

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Embodiments of the invention are described below, with the aid of the drawing ". It shows:

Fig. 1 is a perspective view of a registration device, the is attached to a component to be tested "before inserting a registration plate;

FIG. 2 shows, in a perspective partial illustration similar to FIG. 1, the insertion of a registration plate into the device; FIG.

Fig. 3 in a further perspective partial representation, the closed position, which the protective cover after Inserting the registration plate}

4 shows the components of the registration device according to an exploded perspective view Figures 1 to 3j

Fig. 5 is a partial section along the line 5-5 in Fig. 3j

Fig. B in a perspective partial representation another embodiment of a registration device!

7 "to 9 show a method for producing a registration plate; FIG. and

Figs. 10 to 12 show methods of registering or recording and verifying claim information "in a by means of the method according to FIGS. 9 to 11 produced registration plate.

The registration device shown in Fig. 1 to 3 in the assembled state is suitable for the course of the Register deformation of a component to be monitored or tested when the component is subject to changing loads is exposed to changing tensile and compressive forces, or if the component has no dimensions as a result of thermal

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All expansion or contraction changes. To simplify the representation, a component to be tested is in the form of an elongated one Metal plate P shown.

Referring to Figures 1 and 4, the registration device has an elongated, generally rectangular front or first Base plate 15, which is preferably made of a corrosion-resistant metal, for example stainless steel. the The base plate 15 has an end section 6 which is rigidly connected to the plate P by means of a putty or several screws. A reverse V-shaped rib 17 is formed on the base plate 15 near the end section 16, which ensures that that the cement or the adhesive does not flow backwards or along the base plate 15 beyond the end section 16.

According to FIG. 4, the other end portion of the base plate 15 is provided with a rectangular slot 19, and on this Endafcschnitt two bevels 21 separated by a transverse distance are formed, which protrude outward and so are angled so that they protrude upwards parallel to each other and are opposite each other..Each bevel 21 has one Längssehiitfc 22, and the two longitudinal slots are used for Receiving and guiding matching V-shaped end sections 24 of a generally U-shaped made from this spring wire Locking part 26. This locking part also has a U-shaped handle portion 27, which is by a Slot 2ö protrudes outwards, which in an angled guide block 29 is formed, which is connected to the base plate 15 by 'spot welds, not shown.

Furthermore, the base plate 15 has two tongues 32 which protrude upwards on both sides of the slot 19 and follow are angled inside so that they are opposite each other and delimit narrow slots. The base plate 15 is with three '. generally hemispherical lumps or protrusions 34 provided that protrude above the base plate and

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determine a level support surface. Further, a thin leaf spring having a thickness of about 3NC O _t O75 mm exists, to which a truncated cone-shaped or conical support member and a knob 36 formed iat. The other end of the leaf spring 38 is connected to the base plate 15 near the inner end of the slot 19 by pump welds (not shown), and it has a slot 39 through which the adjacent projection 34 protrudes upwards.

According to Fig. 5 is the support member or the conical button 36 of the leaf spring 3Ö intended to be inserted into the central opening

44 of an annular, disk-like registration plate

45 intervene, which according to the drawing is a Plate is made of sheet metal, but it is also made of other materials can be made. This is discussed in more detail below. The diameter of the central opening 44 the registration plate 45 is slightly smaller than the larger base diameter of the support button 36, so that the registration plate 35 inevitably cooperates with the support button and cannot perform any lateral movements, and that the conical button compensates for any changes in the diameter of the central opening 44 that are due to thermal expansion or contraction of the registration plate 45 are due.

4 is also a rectangular rear or second base plate 50 is present, which is with the to be tested Plate P is connected by means of a putty. This second base plate 50 carries a generally U-shaped hinge plate 52 with two upwardly projecting, parallel bevels 53 separated by a distance Hinge plate 52 has two forwardly projecting tongues 54, which the associated, rearwardly projecting portions of the Overlap base plate 15 and in the delimited by the tongues 32 Slots are slidably guided with respect to the base plate 15. Furthermore, according to FIG. 4, a from bottom to top

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protruding registration atichel 55 present, which is preferably _; consists of diamond and is built into a thin leaf spring 56 which is connected to the SG hinge plate 52 by spot welds, not shown. The leaf spring.56 has a thickness of approximately 0.075 mm and can bend when the registration plate 45 is placed on the support button 36.

The folds 53 of the hinge plate 52, which protrude often, have openings 57 which are aligned with one another and which for this purpose serve, a hinge pin 5Ö in the form of a dowel pin, or the like, which is located on the folds 53 firmly anchored, and on which a generally rectangular protective cover 60 is rotatably mounted, which has a flat o "bere wall 62, to which parallel, separated by a transverse distance side walls 63 adjoin, the have aligned holes 64, of which the Hinge pin 5ö is received with a tight fit. To everyone Side wall 63 of protective cover 60 is joined by an outwardly projecting one that extends in the longitudinal direction Chamfer 66, and each side wall has a longitudinal slot 67. The protective cover 60 is between an in 1 and 2 and a closed position shown in FIG. 3 pivotable} in their closed position the protective cover 60 is held in place by the locking part 26 in a manner to be explained below.

Furthermore, there is a generally rectangular support plate made of thin, stainless spring steel sheet with a thickness of about 0.075 mm, on which two actuators or fingers 70 inclined in opposite directions are formed spot welds rigidly connected, and the resilient fingers 70 are arranged so that they _t with- the top of the recording plate 45 at diametrically-opposed points each

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work together as soon as the protective cover bO according to FIG has been pivoted to its closed position. The resilient fingers can also be designed and arranged so that they cooperate with the outer palm of the registration plate 45.

The following describes the way in which the mechanical device for registering deformations is used use is. An annular registration plate 45 is placed with its opening 44 on the support button 3b and against it the biasing force of the leaf springs 3ö and 5b downwards pressed until it rests against the three projections 34 comes. While the registration plate is in contact with the projections 34 is held, the locking part 2b made of spring wire according to FIG. 2 is pulled outwards or forwards, to cause the inwardly projecting tips of the V-shaped sections 24 at the front ends of the Slots 22 are moved inwardly by cam action. Once the V-shaped sections 24 move inward have shifted, their inner tips protrude over the top of the registration plate 45, so that they the registration plate hold on against the upwardly acting pretensioning forces of leaf springs 3ö and 5b

While the registration plate 45 is held by the retracted locking part 2b, the protective cover bü is pivoted downward into its closed position according to FIG. The locking part 2b is then released, so that the V-shaped sections 24 of the locking part spring outward into the slots bl in the side walls b3 of the protective cover bO. This outward movement of the V-shaped portions 24 causes the inwardly projecting, opposing tips or ends to disengage from the top of the registration plate 45. As soon as the protective cover 60 is closed,

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are according to Pig, 5 the resilient actuators or fingers 30 fixed opposing to the top of Eegistrierplatte at diametrically points, so that they hold the registration plate in light contact with the advantages Bprttngen 34 and the stylus 55 by the leaf spring 56 to the is biased at the top against the underside of the registration plate.

The registration device described above of deformation movements works as follows »If the end section 16 of the front or first base plate 15 relative to the rear or second base plate 50 because the plate P is subjected to stress or executes a thermal expansion or contraction movement, the stylus 55 generates on the underside of the registration plate 45 thereby a scratch mark in that it moves in a radial direction with respect to the registration plate.

This relative movement of the base plates 15 and 50 also causes the resilient actuators or Pinger 70 inevitably continues to turn the recording disk 45 step by step. If the two base plates z. B. at Applying a tensile force to the plate P further away from one another, causes the right resilient finger according to FIG. 4 70 that the registration plate 45 performs a small rotary movement. If, on the other hand, the base plates approach each other, since the plate P is subjected to compression, the left resilient finger 70 causes the registration plate to forcibly is rotated further in the same direction. Thus effect the deformation movements due to stress, that the underside of the registration plate 45 with scratch marks which form a generally zigzag pattern within a generally annular zone. The actuating fingers 70 simultaneously produce marks on the top of the registration plate with each rotary movement, so that it can be seen optically which part of the regi-

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ft

strierplatte "has been used.

Pig. 6 shows a modified embodiment of a mechanical device according to the invention for registering deformations, in which two parallel strips ÖO an elastic plastic foam cemented to the underside of the outwardly protruding folds 66 of the protective cover are, and in which another strip Ö2 made of the same material by means of a putty between the side walls 63 with the outer end portion of the protective cover 60 is connected. A similar strip Ö4 made of an elastic Foam material is cemented to the hinge plate 52 between its upwardly projecting folds 53. These strips made of an elastic foam material create a dust-tight seal between the protective cover bO on the one hand and the base plates 15, 50 and the plate P on the other hand, as soon as the protective cover is in its closed position is pivoted.

FIGS. 7 to 10 generally illustrate the working steps for the production of a generally designated 90 recording plate according to the invention, which essentially consists of a disc-shaped body 91 which consists of a translucent, preferably clear and transparent plastic is made. As a material that turns out to be Has proven suitable for this purpose, is the plastic called, marketed by the General Electric Company under the proprietary name "Lexan" will. The body 91 is immersed with one flat side in an alcoholic solution containing a small percentage contains of xylene, so that the material is dissolved or softened on a flat side of the body 91. Also contains the solution contains a small percentage of a red pigment powder that is soluble in the xylene. There. to this Purpose-appropriate dye is available from GAF Corporation under the trademark "Sudan-3" Brought to market.

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The body 91 of the registration plate remains with his lower part 92 so long immersed in the solution that the dye particles penetrate the body and a red colored Form surface 92, the thickness of which is shown in FIG. 9 for the sake of clarity on a considerably exaggerated scale. represents is. Then the surface 92 of the body 91 is immersed in an alcoholic solution that prevents the penetration of the Xylene interrupts the body and causes the. Area 92 with the red dye particles enclosed in it is solidified again or hardened again. Finally, the body 91 is rinsed with water. It has been shown that both methyl alcohol and isopropyl alcohol are capable of diluting the xylene to a sufficient extent if the dissolving or softening action of xylene on the body 91 "should be terminated. One can adjust the degree of darkness the colored area 92 regulate by changing the concentration of the dye powder dissolved in the alcohol-xylene solution varies, and the depth to which the dye penetrates, Ms, or the thickness of the surface 92 can be regulated in that the concentration of xylene in the alcohol and / or the time during which the surface 92 of the body 91 remains immersed in the alcohol-xylene solution.

According to FIGS. 10 to 12, a registration plate 90 produced in the manner described with reference to FIGS. 5 to 9 provides the advantage that the heat marks are easier and more accurate with the help of an optical viewing or scanning device let evaluate. In other words, the colored area 92 of the body 91 has such properties that the Pointed end of the graver 55 creates incised marks M, which penetrate the surface 92 and extend into the clear, clear material extending into existing part of the body. IM the incised marks M on the registration plate 90 evaluate, one can light rays 95, which can have any color, which is a strong contrast between provides the scratch marks and the remaining parts of the plate,

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either according to Pig. 11 from the colored area 92 or according to FIG. 12 from the other side through the registration plate drop. The light falls through the scratch marks M and forms a strong contrast to the light that passes through the colored area 92 of the body 91 falls. Thus, the light rays 95 can be either optically with the help of a Microscope or with the help of an optical scanning and evaluation device detect or scan. The surface 92 can e.g. B. get a red color, because red light that falls through this area can easily be filtered out with the aid of an optical sensing device.

As can be seen from the above description, the mechanical device according to the invention provides for registration advantages of deformations. Since z. B. the actuator the registration plate 45 at each rectilinear Movement of the base plate 15 relative to the base plate 50 is inevitable, regardless of the direction of movement and turning it further, very clear scratch marks are created that also recognize extremely small stresses and can be easily detected and evaluated.

Further advantages result from the simple structure of the device including the registration plate 45. For example the device is composed exclusively of simple components that can easily be made of sheet metal, e.g. B. stainless steel can be produced. Furthermore, with the exception of the registration plate, there are no rotatable components, and the registration plate need not be provided with a rib or ridge on its periphery. As the actuating finger 70 only work together with the horizontal top of the registration plate, need during manufacture the registration plate no tight tolerances with regard to a cylindrical circumferential surface or the diameter were observed to become so that a cheaper manufacture of the

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Registration plate is possible. Furthermore, one can determine the size of the rotary movement that the registration plate can perform at a certain ' rectilinear movement of the base plate 15 relative to the base plate 50 * vary in a simple manner by that one is the distance of the actuating fingers 70 "from the central axis the registration plate changed accordingly.

Another advantageous feature is that a registration plate 45 can be easily placed on the conical support button 36 when the protective cover has been opened, and that the registration plate can be easily removed after information about stresses has been recorded. characterized in that the resilient locking member is contracted 2b after placing a recording plate on the support button, the registration plate is held against the stylus 55 in the right position. When the protective cover ₍₆₀ closed, therefore, the user can be certain that the registration plate is not has shifted relative to the support button 36, and that it assumes its correct position. The holding of the registration plate by the locking part also proves to be advantageous when the device is attached to the underside of a component to be monitored, for example a wing of an aircraft, Since the "locking part 2b holds the registration plate 45, the registration plate cannot fall down before the protective cover bO is closed and locked.

Another advantageous feature is the pivoting protective cover. bO is formed, which in the closed state protects the registration plate and the stylus and at the same time forms a smooth outer surface. Furthermore, the use of the strips BC, Ii 2 and Ü4 made of an elastic plastic foam on the hinge plate 52 and the protective cover bO in a simple manner offers the possibility of the registration plate and the burin in a dust-proof

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Include closure. Furthermore, the conical peripheral surface of the support button 36 ensures that between the Carrying button and the registration plate 45 no side handle, is present when the device including the registration plate is subject to significant thermal expansion or contraction.

The compressible, tubular, rolled-up hinge pin 5Ö forms a form-fitting articulated connection between the protective cover 60 and the base plate 50, so that there is no play between these components. When the protective cover and the resilient actuating fingers 70 If the device is to be replaced after a long period of use, the hinge pin 5ö can be easily removed. Also the Slideway between the tongues 54 of the hinge plate 52 and the rear end sections cooperating therewith the base plate 15 has the effect that only minimal angular movements can occur between the base plates 15 and 50, if the plate P to be tested is bent.

When the protective cover 60 is closed, of course the resilient fingers 70 that the registration plate is rotated through a small angular amount. Generated here the stylus 55 on the registration plate 45 has a small circular arc Incised mark that can be used as a reference mark. The presence of such a reference mark is desirable, if the scratch marks on the registration plate are to be read and evaluated, and the reference mark indicates when the protective cover 60 is opened and closed again has been. Such a reference mark also shows whether unauthorized persons interfered with during an investigation have made on the device.

The registration plate produced according to FIGS. 7 and 9 forms another important feature of the invention, because the translucent plastic that makes up the main body

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the registration plate is not only cheap, but it 'also makes it possible to select the "area in question on the registration plate to etch or treat them in any other way so that the scratch marks are more clearly recognizable and thereby become more visible let evaluate that one lets light fall on the registration plate, wherein the light pass through the registration plate or can be reflected by them. Such a method for etching the surface 92 can therefore be particularly used use in an advantageous manner because the record plate consisting of the clear, transparent material ■ has a colored area 92 that does not pose a risk of parts flaking off or cracks forming » Furthermore, the colored surface 92 generates light rays, which can be easily filtered out with the help of optical devices let so that essentially only the light is detected which falls through the scratch marks M within the area 92.

Certain modifications can be made within the scope of the invention. For example, you could use the burin 55 and a carrying him, the leaf spring 56 similar spring not on the Hinge plate 52, but on the inner surface of wall 62 the protective cover 60 so that the stylus only cooperates with the registration plate after closing the protective cover. Furthermore, the registration plate be designed as a composite construction and z. B. aufwei- ■ a disk-like inner section made of metal sen, which is enclosed by an annular outer portion, which consists of a further plastic, with which the actuating fingers 70 can work together «

Expectations;

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Claims (22)

EXPECTATIONS / 1 · / Device for mechanical registration of the J? £ deformation movements attributable to stresses a component (P) exposed to alternating stresses on a registration plate (45) with a first holding part (15) which is attachable to the member and it - allows the registration plate to be rotatably mounted, a registration element (55), a second holding part (5O) ₁ which is also attachable to the member and supports the registration element in contact with the registration plate, the registration element movements in a generally radial direction with respect to the Recording plate executes when a linear relative movement occurs between the first and the second holding part in one direction or the other in order to provide the recording plate with markings (M), as well as with an actuating device (70) which serves to control the registration plate in dependence on to rotate the linear relative movement of the first and the second holding part inevitably and stepwise regardless of the direction of the relative movement. 2. Apparatus according to claim 1, characterized in that a to the actuating device first actuating member (70) and a second actuating member (70), which are opposite to the registration plate (45) are arranged substantially diametrically opposite one another and substantially on a line which defines the axis of rotation the registration plate intersects and is at right angles to the direction of the rectilinear relative movements of the first Holding part (15) and the second holding part (50) extends. 3. Apparatus according to claim 2, characterized in that the actuators (70) so an- 309808/08 tt 3 are arranged so that they are disk-like with a radial surface Working together registration plate (4-5). 4. Apparatus according to claim 3, characterized in that the actuating members (70) for this purpose serve to provide the radial surface of the registration plate (45) with markings (M), which on the optical Ytege Indicate the extent to which the registration plate has rotated while using the device. 5. Apparatus according to claim 2, characterized that the actuators generally include flat resilient fingers (70) opposite the Registration plate (45) are inclined in opposite directions. 6. Apparatus according to claim 1, characterized in that a to the first holding part (15) Component (38) belongs which is arranged so that it engages in a central opening (44) of the registration plate (45). 7. The device according to claim 1, characterized ge k e η η that the registration plate (45, 90) has a body (91) made of a transparent plastic, which is provided with a colored radial surface (92). 8. Apparatus according to claim 1,. marked by means which engages the actuators (70) between a first position in engagement with the registration plate (45) and a second position at a distance from the registration plate pivotably supported. 9. Apparatus according to claim 8, characterized in that to the means for supporting the actuating elements (70) include a protective cover (60), furthermore a device which is an articulated connection 309808/0843 between the protective cover and the second holding part (50) "forms and makes it possible to move the protective cover between the first position in which it covers the registration plate (45), and the second position to pivot, and means (26) for securing the protective cover in the first position. 10. The device according to claim 9, characterized in that the articulated connection forming Means aligned openings (64,57) of the protective cover (60) and of the second holding part (50) and has a slotted tubular hinge pin (58) protruding through these openings. 11. The device according to claim 9, characterized in that g e k e η η zue Inet that to the holding device a movable resilient holding part (26) belongs, which has lugs (24) which serve to also the registration plate (45) to hold the first holding part (15). 12. The device according to claim 11, characterized in that the resilient holding part as a locking part (26) is made of spring wire and has a section (27) which can be grasped by hand, to enable the locking member between a first position for retaining the registration plate (45) and a second position for fixing the protective cover (60) and for releasing the registration plate is moved. 13. The apparatus according to claim 1, characterized in that the means for holding the registration plate (4 5) has a spring-loaded extension (36), .der has a conical outer surface which engages in a central opening (44) of the registration plate. 980 0/0842 14. The device according to claim 8, characterized in that the registration plate as a disk-like Registration plate (45) is formed with mutually applied surfaces that too. the actuator includes a set of resilient fingers (70) that are generally diametrically opposed to one another on a diameter of the registration plate are arranged opposite, and that the fingers are arranged so that they cooperate with one of the surfaces of the registration plate, as soon as the actuating device is brought into the first position. 15. The device according to claim 14, characterized in that ^ g e k e η η zei Chnet that to the second holding part (40) a resilient Component (56) belongs, which the registration element (55) in contact with the other surface of the registration plate (45) supports. . 16. The device according to claim 1, characterized in that the first holding part as general rectangular base plate (15) is formed from metal, that the base plate has a substantially flat end portion (16), which is attached to the to be tested by means of a putty Component (P) can be attached, and that the base plate with a rib extending transversely to its longitudinal axis (17) is provided, which limits the flow of the cement on the base plate. 17. The device according to claim 9, characterized in that pieces (80, 82, 84) made of an elastic sealing material are arranged between the protective cover (6Q) and at least one of the holding parts (15, 50) to form a general dust-tight enclosure; for the registration plate (45) and the registration element (55) to be delimited. 18. The device according to claim 16, characterized in that g e k e η η - ζ eich η et that the elastic 8bücke from one one η π η ο 8 / ο ο Sealing "causing plastic foam exist. 19. The device according to claim 1, characterized in that each holding part as a plate (15, 50) is made of metal that the one plate (15) has a section (32) delimiting a slot, and that the other plate (50) has a portion (52) which is slidably guided in the slot to a To prevent bending of the device when bending the component to be tested (P) as much as possible. 20. A method of making a registration plate for use as part of a mechanical device to register deformation movements, g e k e η η zei chnet by the steps that at least one The surface of a body made of a plastic is exposed to the action of a solution containing a dye, to soften the surface of this area and to let the dye penetrate into the area that the depth of the Penetration of the dye into the surface is regulated, and that then the surface containing the dye is hardened again will. 21. The method according to claim 20, characterized in that the solution of alcohol and a small percentage of xylene. 22. The method according to claim 21, characterized in that the surface of the body is made of plastic is rinsed with an alcohol-based solution to remove the xylene and harden the surface again. ! MH) HOfI / Il ■! '! Le e rs eι ie