RU2817806C1 - Thread cutting and locking fastener - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to threaded fasteners. Fastening element includes three thread zones. In the first thread zone the first thread profile with increasing diameter is used. Second thread zone extends from the end of the first thread zone using the first thread cutting profile and continues with a constant diameter. Third thread zone uses a thread fixing thread profile passing along, in fact, the remaining part of the rod of the fastening element.

EFFECT: optimized thread locking mechanism.

12 cl, 19 dwg

Description

Field of technology to which the invention relates

The present invention relates to threaded fasteners.

State of the art

Conventional threaded fasteners (eg, screws or bolts) can be designed to have a self-tapping threading action. One example of such a self-tapping fastener is disclosed in US Patent No. 9,404,524, entitled "High Performance Thread Rolling Screw/Bolt For Use in An Unthreaded Nut Anchor" to Alan Pritchard ( Alan Pritchard), the contents of which are incorporated herein by reference.

Other conventional fasteners may include a thread locking mechanism, which may be achieved, for example, by mechanical interaction between the fastener and the nut member. An exemplary thread-locking fastener is disclosed in U.S. Patent No. 7,722,304, entitled "Fastener and Fastener Assembly" to Alan Pritchard, the contents of which are incorporated herein by reference.

A noted disadvantage of prior art fasteners is that they are optimized for either thread cutting or thread locking, but not both. This forces users to make decisions about which feature is more important for a particular application, which can lead to suboptimal use of such fasteners.

Disclosure of the invention

The disadvantages of the prior art are overcome by providing an exemplary fastener optimized for both thread cutting and thread locking. The fastener comprises two separate threaded profiles distributed over three zones along the fastener shaft. The first zone in which the thread-cutting thread profile is used is immediately adjacent to the entry point of the fastener. Along the first zone, the outer diameter of the thread profile increases along the first, for example, 2-5 thread pitches. The second zone extends from the first zone and uses the same thread cutting profile as the first zone, but maintains a constant external thread diameter. The second zone runs, for example, 2-3 thread pitches behind the first zone. The third zone, which uses a thread locking thread profile, also maintains a constant outside diameter.

In accordance with exemplary embodiments of the present invention, the first and second thread profiles may be selected to complement each other to achieve the desired level of mechanical interaction, i.e. fixing the thread. In addition, when using the present invention, the second thread profile (thread locking) can be optimized to work with the thread created by the first thread profile (thread cutting). This can lead to optimization of the thread locking mechanism.

Brief description of drawings

The above and additional advantages of embodiments of the present invention can be understood from consideration of the accompanying drawings, wherein like reference numerals denote identical or functionally identical elements, in which:

in fig. 1A is a side view of an exemplary fastener in accordance with an illustrative embodiment of the present invention;

in fig. 1B is a long axis view of the head of an exemplary fastener in accordance with an exemplary embodiment of the present invention;

in fig. 1C is a view of an exemplary entry point of an exemplary fastener viewed along the long axis in accordance with an exemplary embodiment of the present invention;

in fig. 2 is an enlarged view of the end of the entry point of an exemplary fastener in accordance with an illustrative embodiment of the present invention;

in fig. 3 shows illustrative views of an exemplary blank for use in forming a fastener in accordance with an illustrative embodiment of the present invention;

in fig. 4A is a cross-sectional view of an exemplary thread profile in accordance with an illustrative embodiment of the present invention;

in fig. 4B is a cross-sectional view of an exemplary thread profile in accordance with an illustrative embodiment of the present invention;

in fig. 4C is a cross-sectional view of an exemplary thread profile in accordance with an illustrative embodiment of the present invention;

in fig. 5A is a cross-sectional view illustrating the interaction of the threads of a nut member and a fastening member in accordance with an exemplary embodiment of the present invention;

in fig. 5B is a cross-sectional view illustrating the interaction of the threads of a nut member and a fastening member in accordance with an exemplary embodiment of the present invention;

in fig. 5C is a cross-sectional view illustrating the interaction of the threads of a nut member and a fastening member in accordance with an exemplary embodiment of the present invention;

in fig. 6 is a sectional view illustrating insertion of an exemplary fastener into a threaded nut member in accordance with an exemplary embodiment of the present invention;

in fig. 7 is a sectional view illustrating insertion of a fastener into a threaded nut member in accordance with an exemplary embodiment of the present invention;

in fig. 8 is a sectional view illustrating insertion of a fastener into a threaded nut member in accordance with an exemplary embodiment of the present invention;

in fig. 9 is a sectional view illustrating insertion of a fastener into a threaded nut member in accordance with an exemplary embodiment of the present invention;

in fig. 10 is a sectional view illustrating insertion of a fastener into a threadless nut member in accordance with an exemplary embodiment of the present invention;

in fig. 11 is a sectional view illustrating insertion of a fastener into a threadless nut member in accordance with an exemplary embodiment of the present invention;

in fig. 12 is a sectional view illustrating insertion of a fastener into a threadless nut member in accordance with an exemplary embodiment of the present invention; And

in fig. 13 is a sectional view illustrating insertion of a fastener into a threadless nut member in accordance with an exemplary embodiment of the present invention.

Carrying out the invention

In fig. 1A is a cross-sectional view of an exemplary thread-cutting and thread-locking fastener 100 in accordance with an exemplary embodiment of the present invention. The fastener 100 includes an entry point 105 and a head 110 with a shaft 115 extending therebetween. Illustratively, entry point 105 is shown as having a substantially flat end. However, it should be noted that in alternative embodiments of the present invention, the fastening element 100 may have an entry point 105 that is round, pointed, etc. Thus, the description of the entry point 105 being substantially flat should be considered as an example only. The head 110 is illustratively shown to be hexagonal in shape for use with an insertion drive. The head 110 extends a length 120 along the same axis of the rod 115 to allow a driving tool, such as a wrench, etc., to engage the head 110 to apply torque to the fastener for inserting the fastener into the wrench element (not shown). The head 110 includes a substantially flat underside 125 that should fit snugly against a nut member (not shown) when the fastener is fully inserted. As will be appreciated by those skilled in the art, the head 110 can take a variety of different shapes depending on the desired drive device. Therefore, the description of the head 110 having a hexagonal shape should be considered as an example only.

The body or shank 115 of the fastener 100 includes a plurality of thread zones, including, for example, a first zone 130, a second zone 135, and a third zone 140. Illustratively, these three zones are used to perform both a thread cutting function and a thread locking function after how the fastener will be inserted into the nut element. Illustratively, the length of the first zone 130 is approximately 2-5 pitches of an exemplary first thread profile extending outward from the core at an angle, with an increasing diameter as the zone moves away from the fastener entry point 105. That is, the outer diameter of the first zone 130 is smallest at the entry point 105 and increases as the threads advance toward the head 110 along the shank 115.

The second zone 135 illustratively contains an additional 1-3 pitches of the first (thread cutting) thread profile, but with a substantially constant outer diameter. As shown in FIG. 1A, the first thread profile illustratively has a cross-section of a thread profile with an angle of substantially 60°. In exemplary embodiments, the first thread profile may include the profile disclosed in US Patent No. 9,404,524, incorporated above by reference. It should be noted that while a specific thread-cutting thread profile is shown and described, the principles of the present invention allow any thread-cutting thread profile to be used in alternative embodiments of the present invention. Therefore, the specific thread-cutting thread profile shown and described herein should be considered as an example only.

The third zone 140 uses a second thread profile, which is illustratively a thread-locking thread profile. As shown in FIG. 1A, an exemplary second thread profile comprises a thread with a 60° angle at the root of the thread that transitions to a 30° angle at the crest. An exemplary thread-locking thread profile is disclosed in US Patent No. 7,722,304, incorporated above. It should be noted that while a specific thread-locking thread profile is shown and described, the principles of the present invention allow any thread-locking thread profile to be used in alternative embodiments of the present invention. Therefore, the specific thread-locking thread profile shown and described herein should be considered as an example only.

Thus, in use, when the fastener 100 in accordance with an exemplary embodiment of the present invention is inserted into the nut member, the threads of the first zone engage the nut member as the fastener is initially inserted. The threads of the first and second zones deform the nut element to create a thread. As you continue to insert the fastener into the nut element, the threads of the third zone engage with the newly created threads, causing a mechanical interaction that causes the occurrence of a locking mechanism. Illustratively, a second thread profile is selected in addition to the first thread profile. In accordance with alternative embodiments of the present invention, two thread profiles can be selected such that the thread locking profile (second thread profile) is made with a priori knowledge of the dimensions of the thread created in the nut element by the thread cutting profile (first thread profile). Since the fastener creates internal threads in the threadless nut element, the thread-locking thread profile can be configured to optimize performance with internal threads. Examples of embodiments are disclosed below in relation to FIGS. 4A, B, C and 5A, B, C.

In fig. 1B is an exemplary view of the head 110 of the fastener 100 as viewed along the long axis of the fastener in accordance with an exemplary embodiment of the present invention. As noted above, the illustration and description of the exemplary hexagonal shaped head should be considered as an example only. In fig. 1C is a view of fastener 100 from entry point 105 along the long axis of the fastener in accordance with an exemplary embodiment of the present invention. As can be understood from Fig. 1C, the fastener shaft 115 has an exemplary shape having several, such as three, segments (lobes) in cross section. It should be noted that the use of a shaft is exemplary only, and the principles of the present invention can be used with fasteners having shafts that are substantially circular. As will be appreciated by those skilled in the art, various types of fastener bar cross-sections can be used to achieve desired fastener properties. More specifically, it is expressly contemplated that rods having more than three segments (lobes) may be used in accordance with alternative embodiments of the present invention. Additionally, in alternative embodiments, the rod may have a variable cross-section. For example, a rod may have a substantially circular cross-sectional area near the entry point, but transition to a non-circular cross-sectional area along the length of the rod. An approximate non-circular cross-sectional area would be, for example, a three-segment (three-lobed) cross-sectional area. However, it is expressly contemplated that other shapes may be used in substantially non-circular cross-sectional areas in accordance with alternative embodiments of the present invention. The principles of the present invention can be used with a wide range of cross-sectional shapes of the fastener shaft 115 to achieve the desired functionality.

In fig. 2 is an enlarged view of the end of the entry point of fastener 100 in accordance with an exemplary embodiment of the present invention. As can be seen from Fig. 2, the outer diameter of the first zone 130 increases as it moves away from the entry point 105. The first zone uses a first thread profile, which is illustratively a thread-cutting thread profile. The second zone 135 continues to use a thread-cutting thread, but with an overall diameter that is essentially constant, unlike the first zone 130, which has an increasing overall thread diameter. The third zone 140 further uses a second thread profile, such as a thread-locking thread profile, for the remainder of the fastener 100.

In fig. 3 illustrates an exemplary head blank 300 for use in forming a fastener 100 in accordance with an exemplary embodiment of the present invention. Illustratively, blank 300 is a single diameter blank, which reduces manufacturing complexity. However, it is expressly intended that the principles of the present invention can be used with more complex workpieces.

In fig. 4A, B, C illustrate thread profiles that may be used in alternative embodiments of the present invention. It should be noted that each thread profile has the same cross-sectional area. Fig. 4A is an exemplary 60° thread profile similar to that shown in FIG. 1. Fig. 4B is representative of an exemplary radius thread profile. Fig. 4C is a representation of an exemplary corner thread shape with a 60730° thread profile. It should be noted that in alternative embodiments of the present invention, different thread profiles can be used. Thus, it is directly intended that the thread profiles shown in FIG. 4A, B, C are exemplary only.

In fig. 5A, B, C illustrate exemplary ranges of potential mechanical interactions that can be achieved by using different thread profiles for nut members and a fastener according to exemplary designs in accordance with exemplary embodiments of the present invention. The various figures show combinations of the thread profiles described above in relation to FIGS. 4A, B, C. As shown in FIG. 5A, B and C, by varying the profiles of the internal and external threads, varying degrees of mechanical interaction can be achieved. In alternative embodiments, by selecting different combinations of thread profiles, the desired amount of mechanical interaction can be achieved.

In fig. 6 is a cross-sectional view 600 of the insertion of a fastener 100 into a threaded nut member 605 in accordance with an exemplary embodiment of the present invention. Threaded nut member 605 illustratively includes a pre-threaded thread 610. View 600 shows fastener 100 and nut 605 immediately prior to insertion of end 105 of fastener 100 into threaded nut member 605. Section view A-A illustrates an exemplary cross-section 615 of fastener 100 and threaded nut element.

In fig. 7 is a cross-sectional view 700 of the insertion of a fastener 100 into a threaded nut member 605 in accordance with an exemplary embodiment of the present invention. In view 700, the first zone 130 and the second zone 135 of the fastener 100 are inserted into the threaded nut element 605. As shown in the enlarged view, a space is left between the first and second thread zones and the internal threads 610 of the threaded nut element 605.

In fig. 8 is a cross-sectional view 800 of insertion of a fastener 100 into a threadless nut member in accordance with an exemplary embodiment of the present invention. In view 800, the threads of the first zone 130 have nearly penetrated the threaded nut member 605, while the threads of the second zone 135 are completely contained within the nut member 605. As shown, the threads of the third zone 140 have formed penetrating points at points 805 within the nut member.

In fig. 9 is a cross-sectional view 900 of the insertion of a fastener 100 into a threaded nut member 605 in accordance with an exemplary embodiment of the present invention. In view 900, the threads of the first zone 130 and the second zone 135 have completely penetrated the nut member 605, and for each internal thread 605 there are penetration points 905 of the crests of the third thread zone 140. When inserting the fastening member 100 as shown in FIG. 9, the apex penetration points 905 form a mechanical locking mechanism, working to secure the fastener into the threaded nut member.

In one exemplary embodiment of the present invention, the thread-cutting profile of the threads of the first and second thread zones is configured to slightly expand the thread diameter of the threaded nut member. This resizing allows the fastener to be designed in such a way as to optimize the interaction between the resized threads and the threads of the third thread-locking zone. By selecting the thread profile and size for the first and second thread zones, the required amount of mechanical interaction with the threads of the third zone can be achieved. However, it should be noted that in alternative embodiments of the present invention, the preformed internal threads are not expanded by the threads of the first and second zones. Therefore, the description of the expandable internal thread should be considered as an example only.

In fig. 10 is a cross-sectional view 1000 of insertion of a fastener 100 into a threadless nut member 1005 in accordance with an exemplary embodiment of the present invention. View 1000 shows a fastener 100 that is inserted into a nut member 1005 having a threadless hole or channel 1010.

In fig. 11 is a cross-sectional view 1100 of insertion of a fastener 100 into a threadless nut member 1005 in accordance with an exemplary embodiment of the present invention. View 1100 shows that the threads of the first and second zones are fully inserted into the threadless nut member.

In fig. 12 is a cross-sectional view 1200 of insertion of a fastener 100 into a threadless nut member 1005 in accordance with an exemplary embodiment of the present invention. The third zone thread 140 has now entered the previously created thread and formed vertex penetrations at points 1205.

In fig. 13 is a view 1300 of insertion of a fastener 100 into a threadless nut member in accordance with an exemplary embodiment of the present invention. In view 1300, threads of the first and third zones have passed through the nut element 1005, with a plurality of threads of the third zone engaging the nut element 1005 at a plurality of apex penetration points 1305.

As noted above, with respect to FIGS. 6-9, in exemplary embodiments of the present invention, the threads of the first and second zones may be sized to create an optimally sized thread to achieve the desired mechanical interaction with the threads of the third zone.

It should be noted that although the present invention has been disclosed in connection with specific thread profiles, the principles of the present invention can be used with a variety of thread cutting and/or thread locking thread profiles. Therefore, specific descriptions of specific thread profiles contained herein should be considered as examples only. In addition, although various descriptions of the number of thread pitches in different zones have been given, those skilled in the art will appreciate that the number of thread pitches in different zones may vary depending on the intended use. Therefore, the description of the specific number of thread pitches in different zones should be considered as an example.

The present description has been written in connection with various illustrative embodiments of the present invention. As will be appreciated by those skilled in the art, various modifications can be made to the embodiments disclosed herein without departing from the spirit or scope of the invention. Thus, the disclosed embodiments should be considered illustrative only.

Claims (27)

1. Fastening element containing: a rod having a cross-sectional profile having an entry point at a first end and a head at a second end, the cross-sectional profile having three or more segments; wherein the rod has a first thread profile applied thereto in a first zone and in a second zone, the first thread profile being a thread-cutting thread profile configured to create internal threads in the nut member; wherein the first zone begins at the entry point and extends a first predetermined number of thread pitches along the rod, the diameter of the first zone increasing from the entry point to the second zone; wherein the second zone has a constant outer diameter and extends a second predetermined number of thread pitches, and a third zone having a second thread profile different from the first thread profile and extending from a transition from the second zone along the remainder of the shaft to the underside of the head, wherein the second thread profile is a thread locking thread profile, and wherein the dimensions of the second thread profile are based on knowledge of a first thread profile to create a desired amount of mechanical interaction between the internal threads formed by the first thread profile and the second thread profile. 2. The fastening element according to claim 1, in which the first thread profile has an angle of 60°. 3. The fastener according to claim 1, wherein the first thread profile has a radius thread profile. 4. The fastener according to claim 1, wherein the first thread profile has a parabolic thread profile. 5. The fastening element according to claim 1, wherein the cross-sectional profile is substantially circular. 6. The fastening element according to claim 1, in which the first specified number of thread pitches is three. 7. The fastening element according to claim 1, in which the second specified number of thread pitches is six. 8. The fastener according to claim 1, wherein the first thread profile is a thread-cutting thread profile. 9. The fastener according to claim 1, wherein the second thread profile is a thread locking thread profile. 10. The fastener of claim 1, wherein the first thread profile is sized to provide an optimized internal thread for engagement with the second thread profile. 11. Fastening element containing: a rod having a cross-sectional profile having an entry point at a first end and a head at a second end, the cross-sectional profile of the rod transitioning from a substantially circular cross-section to a substantially non-circular cross-section; wherein the rod has a first thread profile applied thereto in a first zone and in a second zone, the first thread profile being a thread-cutting thread profile configured to create internal threads in the nut member; wherein the first zone begins at the entry point and extends a first predetermined number of thread pitches along the rod, the diameter of the first zone increasing from the entry point to the second zone; wherein the second zone has a constant outer diameter and extends a second predetermined number of thread pitches, and a third zone having a second thread profile different from the first thread profile and extending from a transition from the second zone along the remainder of the shaft to the underside of the head, wherein the second thread profile is a thread locking thread profile, and wherein the dimensions of the second thread profile are based on knowledge of a first thread profile to create a desired amount of mechanical interaction between the internal threads formed by the first thread profile and the second thread profile. 12. Fastening element containing: a rod having a cross-sectional profile having an entry point at a first end and a head at a second end, the cross-sectional profile of the rod transitioning from a substantially non-circular cross-section to a substantially circular cross-section; wherein the rod has a first thread profile applied thereto in a first zone and in a second zone, the first thread profile being a thread-cutting thread profile configured to create internal threads in the nut member; wherein the first zone begins at the entry point and extends a first predetermined number of thread pitches along the rod, the diameter of the first zone increasing from the entry point to the second zone; wherein the second zone has a constant outer diameter and extends a second predetermined number of thread pitches, and a third zone having a second thread profile different from the first thread profile and extending from a transition from the second zone along the remainder of the shaft to the underside of the head, wherein the second thread profile is a thread locking thread profile, and wherein the dimensions of the second thread profile are based on knowledge of a first thread profile to create a desired amount of mechanical interaction between the internal threads formed by the first thread profile and the second thread profile.