Claims:We claim:

1. A self-locking fastener (100), comprising:
a head (6); and
a shank (1) extending from the head (6), wherein the shank (1) comprises:
a thread section (4) defined along a substantial length of the shank (1); and
a locking section (5) defined by deforming at least a portion of the thread section (4) about a substantial circumference of the shank (1),
wherein, pitch diameter (PDo) of threads in the locking section (5) is less than pitch diameter (PDi) of threads in the thread section (4).

2. The self-locking fastener (100) as claimed in claim 1, wherein the locking section (5) is defined by a major diameter (Di) which is less than a major diameter (Do) of the thread section (4).

3. The self-locking fastener (100) as claimed in claim 1, wherein length of the locking section (5) is about 1.15 to about 1.35 times of the diameter (Do) of the thread section (4).

4. The self-locking fastener (100) as claimed in claim 1, wherein the thread section (4) is deformed by a rolling process to define the locking section (5).

5. The self-locking fastener (100) as claimed in claim 4, wherein the thread section (4) is deformed along at least one of a longitudinal axis (X-X) and a transverse axis (Y-Y) of the shank (1).

6. The self-locking fastener (100) as claimed in claim 1, wherein the thread section (4) is defined between a free end (2) and a head end (3), opposite to the free end (2), of the shank (1).

7. The self-locking fastener (100) as claimed in claim 1, wherein the locking section (5) is defined after at least two pitches of the thread section (4) starting from the free end (2) of the shank (1)

8. The self-locking fastener (100) as claimed in claim 1, wherein the locking section (5) is configured to impart a prevailing torque on a nut, engageable with the thread section (4).

9. The self-locking fastener (100) as claimed in claim 1, wherein the free end of the shank is defined with a chamfer.

10. The self-locking fastener (100) as claimed in claim 1, wherein the locking section (5) is defined by deforming at least a portion of the thread section (4) throughout circumference of the shank (1).

11. A fastener assembly comprising a self-locking fastener (100) as claimed in claim 1.
, Description:TECHNICAL FIELD
The present disclosure, in general, relates to the field of mechanical engineering. Particularly, but not exclusively, the present disclosure relates to a fastener. Further, embodiments of the present disclosure disclose a self-locking fastener.

BACKGROUND OF THE DISCLOSURE
Fasteners are widely employed for joining different components either temporarily or permanently, based on nature of securement. In case of temporary securement, fasteners range from screws, nails, bolts and the like that are employed to pass or intrude through at least one of the components in order to secure the components. Alternatively, the fasteners such as, but not limited to, screws, bolts, nuts, and the like may be configured to pass or intrude through at least one component and engage with another fastener that may be configured to be assembled for securing the components.

The two or more components [or components, in general] that are secured by assembling fasteners may be subjected to vibrations that may be generated or imparted in the component which may result in overhauling or self-loosening. This overhauling or self-loosening commonly occurs in fasteners such as, bolt, screw and nut assembly and the like, where the fasteners share a surface engagement between them to secure the components. Further, during overhauling or self-loosening, the fasteners may be subjected to relative movement at the surface engagement due to which engagement between the fasteners, for example, a bolt and a nut, may decrease or loosen. Such decrease in engagement between the fasteners may render decrease in the securement strength of the components. In some cases, continued overhauling or self-loosening of the fasteners may lead to disengagement of the components.

With advent of technology, efforts have been made to curb self-loosening of the fasteners in order to ensure securement of the components. One such conventional approach is by applying anti-loosening solution [i.e. liquid solution, such as, different microencapsulation] between the surfaces of the fasteners. Such solution may provide rigid adhesiveness between the surfaces to prevent relative movement of the fasteners and inherently enhance engagement strength between the fasteners to secure the components. However, such anti-loosening solution may limit usage of the fasteners in various conditions such as, but not limited to, hydroscopic and corrosive environment, elevated temperatures, and the like. In such conditions, the anti-loosening solution may wither-off from the surface of the fasteners thereby, causing the engagement between the fasteners prone to relative movement.

Additionally, as an alternative to the anti-loosening solution, modifications have been performed in the configuration of the fasteners. Such modifications include the aspect of providing the fastener with a multi-point contact profiles, where the multi-point contact profiles may include, but not limited to, chamfer, ridges, protrusions, and the like, which may anchor on to the component by extending from an engaging surface of the fastener to strengthen the engagement. With enhanced engagement by the multi-point contact profiles, self-loosening and/or overhauling of the fasteners may be prevented. However, as the multi-point contact profiles have minute dimensional tolerances, precision manufacturing of fasteners with such profiles may be a challenge and tedious task. Additionally, manufacturing such multi-point contact profiled in the fasteners in large volumes may not be economical.

The present disclosure is directed to overcome one or more limitations stated above.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the prior art are overcome by a self-locking fastener as claimed and additional advantages are provided through the device as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the present disclosure a self-locking fastener is disclosed. The self-locking fastener includes a head and a shank, where the shank is extending from the head. The shank includes a thread section, defined along a substantial length of the shank. The shank further includes a locking section, defined by deforming at least a portion of the thread section about a substantial circumference of the shank. Further, due to deformation at the locking section, pitch diameter of each thread in the locking section is less than pitch diameter of each thread in the thread section.

In an embodiment, the locking section is defined by deforming at least a portion of the thread section throughout circumference of the shank.

In an embodiment of the present disclosure, the locking section is defined by a major diameter which is less than a major diameter of the thread section.

In an embodiment of the present disclosure, length of the locking section is about 1.15 to about 1.35 times of the diameter of the thread section.

In an embodiment of the present disclosure, the thread section is deformed by a rolling process to define locking section.

In an embodiment of the present disclosure, the thread section is deformed along at least one of a longitudinal axis and a transverse axis of the shank.

In an embodiment of the present disclosure, the thread section is defined between a free end and a head end, opposite to the free end, of the shank. The free end of the shank is defined with a chamfer.

In an embodiment of the present disclosure, the locking section is defined after at least two pitches of the thread section starting from the free end of the shank.

In an embodiment of the present disclosure, the locking section is configured to impart a prevailing torque on a nut, engageable with the thread section.

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

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 illustrates a schematic representation of a self-locking fastener, in accordance with an embodiment of the present disclosure.

Figure 2 illustrates a top view of the self-locking fastener of Figure 1.

Figure 3 illustrates a sectional view of two or more components secured by a member and the self-locking fastener of Figure 1, in accordance with an exemplary embodiment of the disclosure.

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 system and method illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiment thereof has 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.

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, assembly, mechanism, system, method 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 proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or method.

Embodiments of the present disclosure disclose a self-locking fastener. The self-locking fastener includes a head and a shank, where the shank extends from the head. The shank includes a thread section, defined along a substantial length of the shank. The shank further includes a locking section, defined by deforming at least a portion of the thread section about a substantial circumference of the shank. Further, due to deformation at the locking section, a pitch diameter of each thread in the locking section is less than the pitch diameter of each thread in the thread section. This configuration of the self-locking fastener is configured to impart a prevailing torque on a member such as a nut that is engageable with the thread section, for securing one or more components. Thus, a member, such as a nut, may fail to overrun the locking section of the fastener and hence, avoid self-loosening of the fastener thereby, securing components.

In an embodiment, the thread section of the shank may include substantially uniform parameters such as, but not limited to, a pitch of thread, a depth of thread, pitch diameter of the thread and the like, along the length of the shank. The term “pitch” may refer to as a distance between a point on a crest and a corresponding point on a trough of a specific thread, measured about the transverse axis (Y-Y) of the fastener. The term “pitch diameter” refers to a diameter measured at half way between the crest and troughs of the threads. Further, the term “depth” may refer to a distance between a lower most point in the trough to a highest point in the crest, of a specific thread.

The disclosure is described in the following paragraphs with reference to Figures 1 and 2. In the figures, the same element or elements which have same functions are indicated by the same reference signs. It is to be noted that, combination or assembly of self-locking fasteners is not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate that the configuration self-locking fastener as disclosed in the present disclosure can be used in any fastener including but not liming to bolts, nuts, screws, threaded washers and the like.

Figure 1 is an exemplary embodiment of the present disclosure which illustrates a self-locking fastener (100). The self-locking fastener (100) [hereinafter also referred to as “fastener (100)] includes a shank (1) and a head (6), where the shank (1) is configured to extend from the head (6) of the fastener (100). Further, the shank (1) may be configured pass or intrude through at least one component [not shown in figures], which may be required to be fastened. The at least one component may be configured to extend between a head end (3) of the shank (1) and till a free end (2) of the shank (1). That is, the head end (3) refers to an end of the shank (1) corresponding to the surface of the head (6) from which the shank (1) extends, while the free end refers to an end of the shank (1) which is opposite to the head end (3) of the shank (1) and is configured to initially engage the at least one component. In an embodiment, the free end (2) of the shank (1) may be adapted to receive at least one of a nut, a washer, an anchor member, and the like, which may adaptably assist the fastener (100) in securing the at least one component.

Further, in an embodiment, the shank (1) may be an elongated member, having a predefined length along a longitudinal axis (X-X) and a predefined spread (or also referred to as diameter, based on cross-section) along a transverse axis (Y-Y). The predefined length of the shank (1) may be greater than the spread of the shank (1). In the illustrative embodiment, the shank (1) includes a cross-sectional profile resembling a circle, defined along the transverse axis (Y-Y), however, a portion of the shank (1) may also include profiles such as, but may not be limited to, ellipse, square, and the like, for gripping the fastener (100). The shank (1) may be defined with a thread section (4) on its circumference and along a substantial length of the shank (1), where initiation (or also referred to as “start for threads”) of the thread section (4) may be defined at the free end (2) of the shank (1). The thread section (4) may be defined from the free end (2) of the shank (1) and may extend till a predetermined distance (L1) from the head end (3) of the shank (1), based on application of the fastener (100). The thread section (4) may be configured to receive a member (not shown in figures) such as, but not limited to, a nut, which may be operated from the free end (2) towards the head end (3) of the shank (1), for assisting the fastener (100) to secure the at least one component. Further, the shank (1) may be defined with a chamfer at the free end (3) in order to suitably receive the member for operating through the thread section (4) and secure the at the least one component.

In an embodiment, at least a portion of the thread section (4) may be deformed, in order to define a locking section (5) of the fastener (100). The locking section (5) may be defined about a substantial circumference of the shank (1). The term ‘substantial circumference’ may infer that the deformation of the thread section (4) may be performed about the transverse axis (Y-Y) of the fastener (100) throughout, about 3600 of the circumference of the shank (1). For example, a region of the thread section (4) may be deformed completely about the circumference of shank (1) in order to form the locking section (5). This region of deformation may be dependent on the parameters of the fastener (100) including, but not limited to, pitch diameter of the thread section (4), major diameter of the thread section (4), major diameter of the shank (1), required pitch diameter of the locking section (5), major diameter of the locking section (5), profile of the threads in the thread section (4), pitch of threads in the thread section (4), and the like. In an embodiment, length (L2) of the region of the locking section (5) is about 1.15 to about 1.35 times of the major diameter (Do) of the thread section (4). However, such dimensional factors may vary in accordance with profile of the threads in the thread section (4). Due to such dimensional factors, the pitch diameter (PDo) of each thread in the locking section (5) is less than pitch diameter (PDi) of each thread in the thread section (4).

Further, the locking section (5) may be defined on the thread section (4) in such a way that, the locking section (5) includes portion of the thread section (4) on its either sides. In an embodiment, the locking section (5) may not be performed at either of the free end (2) or the head end (3) of the shank (1). In an embodiment, the locking section (5) may be defined proximal to the free end (2) of the shank (1). For example, the locking section (5) may be defined after at least two pitches of the thread section (4) from the free end (2) of the shank (1), however, the number of pitches from the free end (2) for defining the locking section (5) in the fastener (100) may be varied based on application and configuration of the fastener (100). The at least two pitches of the thread section (4) may provide initiation of fastening when required torque is applied to the member, for example a nut, in order to assist the fastener (100) in securing the at least one component. Further, as the locking section (5) may be defined after the at least two pitches, increased torqueing force may be applied on the member to overrun the locking section (5) for securement. Also, as the locking member of the fastener (100) may precede the member engaging and securing the at least one component, the locking section (5) may be configured to restrain the member from relative back movement towards the free end (2) of the fastener (100) thereby, avoiding self-loosening of the fastener (100), and in-turn, securement of the at least one component, as best can be seen in Figure 3.

In the illustrative embodiment, the deformation of the thread section (4) may be performed by subjecting the thread section (4) to a rolling process. The thread section (4) may be deformed along at least one of a longitudinal axis (X-X) and a transverse axis (Y-Y) of the shank (1). The threads of the thread section (4) may be subjected to axial compression stress by one or more rollers employed for the rolling process. Such axial compression stress may cause depression in depth, at the same time, bulging of the threads in a direction along the longitudinal axis (X-X) of the fastener (100). Due to such deformation in the threads of the thread section (4), torqueing force required for securement of the at least one component may increase. On applying the required increased torqueing force, the member may annul the deformation of the threads to overrun the locking section (5) and threadably engage the at least one component for securement. Further, during vibration of either the fastener (100) or the at least one component, the member may be subjected to relative movement on the threads of the thread section (4). The locking section (5), however, may be configured to impart a prevailing torque on the member, engageable with the thread section (4). The prevailing torque may be referred to as the additional torque required for overrunning the deformation in the threads about the locking section (5) of the fastener (100).

In an embodiment, the fastener (100) may be defined to include only the shank (1) having thread section (4) on its either end, without provision of the head (6). The shank (1) may be defined with the free end (3) on its either ends, where the member may be selectively fastened from at least one end of the fastener (100) to secure the at least one component. The thread section (4) may be defined throughout the length of the shank (1). The locking section (5) may be defined on at least one end of the shank (1) to impart prevailing torque, however, multiple portions of the thread section (4) may be deformed to produce the locking section (5) at selective regions of the shank (1).

In an embodiment, the shank (1) and the head (6) of the fastener (100) may be made by a manufacturing process including, but not limited to, extrusion, pultrusion, rolling, casting, machining, resin moulding, powder metallurgy, and the like. Further, the shank (1) and the head (6) may be defined as an integral component of the fastener (100) or may be joined as separate components to form the fastener (100). That way, the shank (1) and the head (6) of the fastener (100) may be made from homogeneous material or may be made from heterogenous material. The material in which the shank (1) and the head (6) may be made includes at least one of metals, non-metals, polymers, alloys, and the like.

In an embodiment, the head (6) may be defined with various profiles including, but not limited to, a square, a rectangle, hexagonal, hex-lobular, and the like. In the illustrative embodiment, the head (6) may be defined with hexagonal profile as illustrated in Figure 2. Further, the head (6) may be provisioned with a washer (8) that may either be integrally formed with the head (6) or may be separately engageable with the head (6).

In an embodiment, the first thread section (4) may be made from thread profile including, but not limited to, screw or V-threads, square threads, ACME threads, trapezoidal threads, saw-tooth threads and buttress thread.

In an embodiment, the shank diameter (Ds) may be equal to the major diameter (Do) of each thread in the locking section (5) or may be configured to be less than or greater than the major diameter (Do) of the locking section (5).

EQUIVALENTS

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

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.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

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.

Referral numerals:
Particular Numeral
Fastener 100
Body 1
One end 2
Other end 3
Thread section 4
Locking section 5
Head 6
Neck 7
Washer 8
Defined distance L1
Predetermined length L2
Pitch diameter of thread section PDi
Pitch diameter of locking section PDo
Major diameter of thread section Di
Major diameter of locking section Do