Description:‘SUPPORT MECHANISM TO MACHINE EXTREMELY SHALLOW SIDE GROOVING FOR STRAIGHTER PROPAGATION OF CRACK’

FIELD OF INVENTION:
[001] The present invention is directed to Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack.

[002] The present invention relates to a mechanism used as a support to facilitate slot cutting (side grooving) of approximately 0.25mm deep in line with the notch using Electric Discharge Machining (EDM). The slot is mandatory to maintain the straightness of the crack propagation in fracture mechanics studies using compact tensile (CT) samples.

BACKGROUND OF THE INVENTION:
[003] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[004] While conducting fracture mechanics, studies like fatigue crack growth rate studies of linear elastic fracture mechanics or elastic-plastic fracture mechanics studies, is a mandatory requirement to side groove the compact tensile test sample in line with the notch root of the sample as per ASTM standards E1820, E 647, E 399 etc. The side grooving is useful to force the crack propagation in a straight line and avoid deviations from the original plane. The standard CT samples are of 25 mm thickness and it is easy to produce a side groove in the shape of ‘V’ of depth 2 mm all along the specimen starting from the root of the pre-existing notch. A slotting machine or a V cutter in milling machine is sufficient to create a side groove of 2mm depth for a 25mm standard CT sample. Whereas if the test is done on 6mm to 8 mm thick sample, making a side grooving of 2 mm deep on either sides is not acceptable as the effective thickness remaining will be too low to conduct a test. In that context, very shallow grooving of approximately 0.25mm deep is appreciable. But grooves of such very small depth is not possible with slotting or milling machines. EDM is the only option to perform the side grooving in such thin samples.

[005] In view of the above, the present invention has been proposed.

OBJECTS OF THE INVENTION:
[006] Primary objective of the invention is to design and fabricate a support mechanism used to machine extremely shallow side grooving using EDM in a CT sample for straighter propagation of crack.

[007] Another object of the invention is to provide Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack, which is simple in construction.

[008] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.

SUMMARY OF THE INVENTION:
[009] One or more drawbacks of conventional systems and process are overcome, and additional advantages are provided through the apparatus/composition and a method 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 part of the claimed disclosure.

[0010] The side grooving for a CT sample in fracture mechanics study is a standard procedure in such tests. The standard side groove size is 2 mm deep sharp cut. These are practically applicable for samples of thickness around 25 mm. But when the thickness of the test sample is lower in rage of 6 mm to 8 mm such 2mm deep side grooves are unacceptable. Hence side grooves of depth as low as 0.25 mm are required. In the invention a mechanism to create such shallow groove is devised and used along with EDM for side grooving purpose.

[0011] According to the invention, there is provided a Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack comprising of a base plate (1) with holes suiting the EDM female threads, in which the base plate (1) is connected to a Vertical plate (2) with step (7) to support the CT sample.

[0012] The CT sample is fastened through holes (3,4) to the vertical part (2) of the mechanism and the base plate (1) of mechanism is fastened to the EDM bed through holes (5,6).

[0013] The base plate (1) is integrally connected to the vertical plate (2) with the step (7) so as to constitute a single structure.

[0014] The vertical plate (2) is provided at one side of the base plate (1). The vertical plate (2) partially covers the side of the base plate (1).

[0015] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

[0016] 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.

[0017] 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 ACCOMPANYING DRAWINGS:
[0018] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and processes that are consistent with the subject matter as claimed herein, wherein:

Figure 1: Shows the isometric view of Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack according to the present invention.

[0019] The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily 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.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION WITH REFERENCE TO THE ACCOMPNAYING DRAWING:
[0020] 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.

[0021] The invention makes a disclosure regarding a technology pertaining to Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack.

[0022] Now, reference may be made to figure 1, wherein the CT samples can be fastened to part 2 of figure 1 for the side grooving. The part 1 of the Support Mechanism is fastened to the bed of the EDM through holes (5,6) which enable the mechanism to be rigid and with zero degree of freedom. The CT sample can be kept on the step (7) provided in part 2 of the Support Mechanism. The step provides the seating support for the sample as well as avoids the rotation of the sample in the vertical plane. However, the vertical movement is yet to be arrested. This complete movement arrest can be done by fastening the CT sample on to the holes 3,4 using a threaded bolt. Once this holding of the sample is done, the EDM wire can approach in the vertical line exactly bisecting the holes (5 and 6) in the part 1 of the present invention. The feed rate of the EDM wire can be maintained to the required depth of the side grooving required, for example 0.25 mm.

[0023] Thus, the Support Mechanism of the instant invention to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack comprising of a base plate (1) with holes suiting the EDM female threads connected to a Vertical plate (2) with step (7) to support CT sample, wherein the CT sample is fastened through holes (3,4) to the vertical part (2) of the mechanism and the base plate (1) of the mechanism is fastened to the EDM bed through holes (5,6).

ADVANTAGES:
- Extremely Shallow Side grooves of depth as low as 0.25 mm;
- Portable

[0024] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases, it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[0025] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

[0026] 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 particulars 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 analogues 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”.

[0027] The above description does not provide specific details of manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.

[0029] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.

[0030] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
, Claims:WE CLAIM:

1. A Support Mechanism to Machine Extremely Shallow Side Grooving Using EDM in a CT Sample for Straighter Propagation of Crack comprising of a base plate (1) with holes suiting the EDM female threads, in which the base plate (1) is connected to a Vertical plate (2) with step (7) to support the CT sample.

2. The Support Mechanism as claimed in claim 1, wherein the CT sample is fastened through holes (3,4) to the vertical part (2) of the mechanism and the base plate (1) of mechanism is fastened to the EDM bed through holes (5,6).

3. The Support Mechanism as claimed in claim 1 or 2, wherein the base plate (1) is integrally connected to the vertical plate (2) with the step (7) so as to constitute a single structure.

4. The Support Mechanism as claimed in claims 1-3, wherein the vertical plate (2) is provided at one side of the base plate (1).

5. The Support Mechanism as claimed in claim 4, wherein the vertical plate (2) partially covers the side of the base plate (1).