Claims:We claim:
1. An anti-buckling device (100) for a low cycle fatigue testing of a thin sheet metal (101), the anti-buckling device (100) comprising of:
two identical plates (102), each of the two identical plates (102) having two rectangular slots (102b, 102c);
four through holes (102d) provided on each of the two identical plates (102) to mount the one identical plate (102) over the other identical plate (102) by a plurality of screw and nuts (103, 103a);
the thin metal sheet (101) sandwiched between the two identical plates (102) to prevent from buckling; and
an extensometer (104) clipped to the thin metal sheet (101) through the two identical slots (102b, 102c) of the two identical plates (102) to obtain strain data during the low cycle fatigue testing.

2. The anti-buckling device (100) as claimed in claim 1, wherein the two identical slots (102b, 102c) are separated by a center support member (102a).

3. The anti-buckling device (100) as claimed in claim 1, wherein material of the anti-buckling device (100) is stronger than the thin sheet metal (101).

4. . An anti-buckling device (100) for a low cycle fatigue testing of thin sheet metal (101), the anti-buckling device (100) comprising of:
two identical plates (102), each of the two identical plates (102) having two rectangular slots (102b, 102c); and
four through holes (102d) provided on each of the two identical plates (102) to mount the one identical plate (102) over the other identical plate (102) by a plurality of screw and nuts (103, 103a).

5. The anti-buckling device (100) as claimed in claim 5, wherein the two identical slots (102b, 102c) are separated by a center support member (102a).
6. The anti-buckling device (100) as claimed in claim 5, wherein material of the anti-buckling device (100) is stronger than the thin sheet metal (101).

7. The anti-buckling device (100) as claimed in claim 5, wherein the anti-buckling device (100) receives the thin metal sheet (101) in between the two identical plates (102) to prevent from buckling.

8. The anti-buckling device (100) as claimed in claim 5, wherein the anti-buckling device (100) receives an extensometer (104) through the two identical slots (102b, 102c) of the two identical plates (102) and clipped to the thin metal sheet (101) to obtain strain data during the low cycle fatigue testing.
, Description:ANTI-BUCKLING DEVICE (ABD) FOR LOW CYCLE FATIGUE TESTING OF THIN SHEETS
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to metal fatigue testing technology to test mechanical properties of metal sheets and, in particularly, to anti-buckling device (ABD) in low cycle fatigue testing of thin metal sheets to avoid buckling of the thin metal sheets under tension compression mode.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART:
[002] In current modern world, thin metal sheets are used at many places, such as automobile bodies (commercial as well as personal), airplane fuselages and wings, medical tables, roofs for buildings (architecture) and many other applications. In the automobile industry, safety and reliability of the automobile is prime concern where material fatigue performance of the metal sheet plays important role for safety and reliability of the automobile. Therefore, low cycle fatigue testing of the metal sheet at high strain identifies the strength of the sheet metal for safety and reliability of the automobile or different applications.
[003] In the low cycle fatigue testing of the thin sheet metal, buckling of sheet is the major technical problem in the testing apparatus. Buckling of the thin sheet metal in the low cycle fatigue testing impacts the strain data and creates hurdle in completion of tests (low cycle fatigue experiment) and the testing fails.
[004] Chinese patent publication CN205749099U discloses a flat cold rolled sheet hangs down anti bucking device of all fatigue test, including the centre gripping at the sheet metal sample just, the anti bucking board of two sets of length and the short anti bucking board on anti - two sides, long anti bucking board all is T shape structure with short anti bucking board, both have seted up firstly respectively in the pterygoid lamina both sides, two circular through -holes, both have seted up firstly by the web upper surface, two outer casing locating screw holes, the web top of long anti bucking board is equipped with the rectangle draw runner that the sectional area is less than the web, the web top of short anti bucking board be equipped with rectangle draw runner grafting complex rectangle spout, the web upper surface of long anti bucking board and short anti bucking board is equipped with the outer casing, has set up on the outer casing and first, two outer casing locating screw holes complex waists shape hole, the anti bucking board of two sets of length is fixed through locking bolt locking respectively with short anti bucking board, the same side of web of long anti bucking board and short anti bucking board is equipped with elastic supporting sheet respectively.
[005] Chinese patent publication CN202582979U discloses a soil sample uniaxial direct tensioning device. The soil sample uniaxial direct tensioning device is used to connect a soil sample and a device in a soil sample tension test and comprises two cylindrical soil sample clamping devices which are arranged symmetrically. Each soil sample clamping device is formed by combination of two semi-cylindrical fastening parts, a semi-circle diameter-changing groove channel is arranged in each inward side of the fastening parts in digging mode, the outer back portion of the semi-circle diameter-changing groove channel expands, and a connecting screw hole used to combine and fix two fastening parts is arranged in each outward side of the fastening parts in penetrating mode. In the process of conducting tensile tests, after placing two ends of a soil sample into diameter-changing groove holes of the soil sample uniaxial direct tensioning device which is open symmetrically, users utilize screws to connect fastening parts of the clamping device fixedly and fix the soil sample in the tensioning device, and then uniaxial direct tensioning strength of soil can be measured accurately by exerting tension on two ends of the tensioning device. The soil sample uniaxial direct tensioning device has the advantages of guaranteeing that the soil sample fractures along the middle of the soil sample in the process of tensioning and removing influence of the clamping device on the soil sample completely, thereby guaranteeing test data to be accurate and reliable.
[006] Chinese patent publication CN202013310U discloses a testing device used for realizing sheet pulling/pressing fatigue crack growth in corrosive environment. The testing device comprises anti-buckling plates, corrosive boxes and a leakage-proof tray and is characterized in that a sheet long crack growth MT test sample is clamped between the front anti-buckling plate and the rear anti-buckling plate by bolts, a rectangular hole used for observing the crack growth is arranged at the canter of the anti-buckling plates, a front corrosive box and a rear corrosive box are respectively inserted into the rectangular hole of the two anti-buckling plates and are closely adhered to the surface of the test sample, two ends of the corrosive boxes are respectively provided with a water inlet and a water outlet, the upper ends of the two corrosive boxes are provided with a vent hole, and the leakage-proof tray passes through the test sample and is positioned below the anti-buckling plates. Compared with the prior art, the testing device can effectively prevent the test sample from bending under the action of compressive load, and test equipment and the anti-buckling plates do not suffer corrosion damage when corrosive solution flows through the crack surface, therefore, the crack growth process of the test sample can be clearly observed in the corrosive solution environment.
[007] Chinese patent publication CN106697504A discloses a geological sample storing device for physicochemical detection. The device comprises a baffle; first glass plates, second glass plates and vacuum generation units are installed on the two sides of the baffle, buckle units are connected to the four sides of each second glass plate, and a first rubber frame is installed outside each second glass plate; a protective frame is installed on the periphery of each first glass plate, the right side of each first glass plate is connected with a disinfectant tank, and second rubber frames, physical sample containers and fixing units are installed below the second glass plates; and chemical sample containers are installed on the right sides of the physical sample containers, the fixing units are connected to the two sides of the sample containers, and each fixing unit comprises a button, a disengaging rod, a magnet and a supporting rod. According to the geological sample storing device for physicochemical detection, by arranging a series of structures, geological samples can be more intactly stored, research detection is facilitated, and the practical application value is achieved.
[008] In the existing anti-buckling device, there are several challenges and dis-advantages. The existing anti-buckling device requires large number of parts which need to be join with each other by a plurality of nut bolts. Assembly of large number of parts increases cost, weight of device and time of assembly, further, there are high chances of failure of any part during use, accordingly, the existing anti-buckling device has less durability and high serviceability. Another disadvantage associated with the existing anti-buckling device are high weight, high cost and with high probability of loss of small parts. Also, the device does not have the provision of clamping it on one of the surface of the sheet sample at the gauge section and get the strain of the sample during the experiment.
[009] It would be beneficial to develop an Anti-buckling device which can be used for low cycle fatigue testing of sheet metal by overcoming the above-mentioned technical problems. Therefore, there is a need in the art to have a newly design and structured Anti-buckling device which is cost effective and simple in structure to avoid buckling of thin sheet in the low cycle fatigue testing.
[0010] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
[0011] OBJECTS OF THE INVENTION:
[0012] It is therefore the object of the invention to overcome aforementioned and other drawbacks in prior device/system/apparatus.
[0013] The principal objective of the present invention is to provide an anti-buckling device to be used for low cycle fatigue testing of thin metal sheet to avoid buckling of the thin metal sheet under tension compression mode.
[0014] Another object of the present invention is to provide the anti-buckling device with rectangular shape structure.
[0015] Another object of the present invention is to provide the anti-buckling device which allows fast and efficient fitment of extensometer over the thin metal sheet for obtaining strain data during testing.
[0016] Yet another object of the present invention is to provide the anti-buckling device which is cost efficient, easy to manufacture, lesser number of parts, and avoids buckling of thin metal sheet during tension compression mode.
[0017] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
[0018] One or more drawbacks of conventional anti-buckling device for low cycle fatigue testing of thin sheet metal are overcome, and additional advantages are provided through the anti-buckling device as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0019] The present subject matter relates to an anti-buckling device for a low cycle fatigue testing of thin sheet metal under tension compression mode. The anti-buckling device includes two identical plates where each of the two identical plates having two rectangular slots. The anti-buckling device has at max four through holes provided on each of the two identical plates to mount or position the one identical plate over the other identical plate by a plurality of screw and nuts. Further, the thin metal sheet is sandwiched between the two identical plates to prevent from buckling and an extensometer is clipped to the thin metal sheet through the two identical slots of the two identical plates to obtain strain data during the low cycle fatigue testing under tension compression mode.
[0020] In an embodiment, the two identical slots are separated by a center support member which prevents the thin sheet metal from being buckling during testing.
[0021] In an embodiment, material of the anti-buckling device is stronger than the thin sheet metal to be tested on the low cycle fatigue testing machine or apparatus.
[0022] In an embodiment, the two rectangular slots are in horizontal position in one over the other.
[0023] In an embodiment, the extensometer is clipped over the thin sheet metal to obtain all strain data during testing.
[0024] In yet another embodiment of the present subject matter, an anti-buckling device for a low cycle fatigue testing of thin sheet metal under tension compression mode. The anti-buckling device includes two identical plates where each of the two identical plates having two rectangular slots and four through holes provided on each of the two identical plates to mount the one identical plate over the other identical plate by a plurality of screw and nuts.
[0025] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
[0026] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0028] Fig. 1 illustrates structure of anti-buckling device for low cycle fatigue testing of thin sheet metal, in accordance with an embodiment of the present subject matter;
[0029] Fig. 2 illustrates front view of the anti-buckling device as illustrated in figure 1, in accordance with an embodiment of the present subject matter; and
[0030] Fig. 3 illustrates rectangular plate structure of the anti-buckling device as shown in the figure 1, in accordance with an embodiment of the present subject matter.
[0031] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0032] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
[0033] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
[0034] The present subject matter relates to an anti-buckling device for a low cycle fatigue testing of thin sheet metal under tension compression mode. The anti-buckling device includes two identical plates where each of the two identical plates having two rectangular slots. The anti-buckling device has four through holes provided on each of the two identical plates to mount or position the one identical plate over the other identical plate by a plurality of screw and nuts. Further, the thin metal sheet is sandwiched between the two identical plates to prevent from buckling and an extensometer is clipped to the thin metal sheet through the two identical slots of the two identical plates to obtain strain data during the low cycle fatigue testing under tension compression mode.
[0035] The present subject matter relates to prevent buckling of thin sheet metal during low cycle fatigue testing.
[0036] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0037] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0038] Fig. 1 illustrates structure of anti-buckling device to be used for low cycle fatigue testing of thin sheets to prevent buckling under tension compression mode, in accordance with an embodiment of the present subject matter. The anti-buckling device 100 comprises of two identical plates 102 each of the two identical plates 102 having two rectangular slots 102b, 102c. Further, each identical plate 102 of the anti-bucking device 100 comprises of four through holes 102d at corners which exactly matches with four through holes 102d on the other identical plate 102. Through four through holes 102 both the identical plates 102 mount with each other through a plurality of screw and nuts 103, 103a. Referring to figure 1 and 2, screws from the plurality of screw and nuts 103, 103a can be either of allen head or normal such that it can just pass through the holes present on the identical plates 102. Each of the identical plate 102 have a center support member 102a in between the two identical slots 102b, 102c. As shown in the figure 3, the two identical slots 102b, 102c are separated by the center support member 102a.
[0039] Referring to figure 1 and 2, the thin metal sheet 101 is sandwiched in between the two identical plates 102 to prevent buckling. The center support member 102a prevents buckling and going out of plane of the thin sheet metal 101 during low cycle fatigue testing when load is compressive. Since each plate 102 is present on either side of the thin sheet metal 101 so the thin sheet metal 101 is prevented from buckling from both the sides.
[0040] As shown in the figure 1 and 2, the thin sheet metal 101 which is to be tested on the low cycle fatigue testing machine is sandwiched between two identical plates 102. The plates 102 are kept in such a way that their identical profile gets superimposed or matches over each other. The plates 102 are fastened with the help of screw 103 and nut 103a in such a way that the screw and nut can be easily unclamped through hand without using any tool. The plates 102 should not be fastened loose or tight. Proper fastening of the plates 102 is very essential for proper experimental/testing result.
[0041] In an embodiment of the present subject matter as illustrated in the figure 1 and 2, an extensometer 104 is clipped to the thin metal sheet 101 through the two identical slots 102b, 102c of the two identical plates 102 to obtain strain data during the low cycle fatigue testing. The clip of the extensometer 104 maintains contact against the thin metal sheet 101 during testing. The extensometer 104 has clips 104a, 104b which passes through the two rectangular slots 102b and 102c of the anti-buckling device 100 to attach the extensometer 104 with the thin sheet metal 101 for obtaining the strain data during testing.
[0042] In yet another embodiment of the present subject matter, the low cycle fatigue testing machine grips the thin sheet metal 101 just near the anti-buckling device 100 leaving a gap of about 1 to 2mm between the anti-buckling device 100 and the grip of the low cycle fatigue testing machine at both ends. The Low Cycle Fatigue test is carried out in strain control mode oscillating between tension and compression mode. During compression mode, the anti-buckling device 100 prevents the thin sheet metal 101 from buckling and the clip extensometer 104 clamped with the thin sheet metal 101 through the rectangular slots 102b, 102c of the two identical plates 102 continuously gets the data from the thin sheet metal 101.
[0043] Referring to figure 3 which illustrates structure of the plate 102 of the anti-bucking device 100. The anti-buckling device 100 comprising of two identical plates 102 where each of the two identical plates 102 having two rectangular slots 102b, 102c one over another in horizontal position. Further, the two identical plates 102 comprises of four through holes 102d to mount the one identical plate 102 over the other identical plate 102 by a plurality of screw and nuts 103, 103a. The two identical slots 102b, 102c are separated by a center support member 102a which prevents buckling of the thin metal sheet 101 during testing.
[0044] In an embodiment, the material of construction of the anti-buckling device 100 is stronger than the thin sheet metal 101 to be tested. The material of the anti-buckling device 100 should be strong enough to overcome the force exerted by the thin sheet metal on the central support member 102a of the anti-buckling device 100 as shown in Figure – 2, during compression load mode or buckling action to prevent buckling of the experimental thin sheet metal 101.
[0045] In an embodiment, the anti-buckling device 100 receives the thin metal sheet 101 in between the two identical plates 102 to prevent from buckling with the help of the center support member 102a.
[0046] In another embodiment of the anti-buckling device 100 receives an extensometer 104 through the two identical slots 102b, 102c of the two identical plates 102 and clipped to the thin metal sheet 101 to obtain strain data during the low cycle fatigue testing. It is important to fix or clamp the extensometer 104 with the thin sheet metal 101 during Low Cycle Fatigue testing of the thin metal sheet to get the experimental data from the sheet metal specimen 101.
Advantages of the Invention over prior art:
[0047] The present structure of Anti-buckling device prevents buckling of thin sheet samples during Low Cycle Fatigue experiments and facilitates fixing clip extensometer on the gauge section of the thin sheet metal to get the data from the thin sheet metal sample.
[0048] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0049] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0050] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.