CA2063164C - Threaded and non-threaded fastener improvements - Google Patents

Abstract

Most mechanical joints, both sealed and not sealed use either threaded fasteners such as conventional nuts, bolts and set screws or non-threaded fasteners such as conventional spring pins. Safety, economy, reliability and environmentability of structures, piping systems, both portable and fixed, their combination, mechanical equipment, power plants, jet liners, ships, etc., rely on the predictable performance of involved fasteners.
Due to the variety of factors, a predictable performance of corresponding commercial fasteners is not always fully attainable.
Such uncontrollable conditions as in-service thermal cycling, vibration, metal flattening, metal fatigue, human error, possible malpractice, tampering with or neglect, occuring during installation, operation or maintenance, make performance prediction difficult and increase associated costs.
This invention comprises a number of value-added improvements of commercial fasteners which may significantly increase the accuracy of prediction in safety, economy, reliability and environmentability of involved systems if proposed improved fasteners are used.
Related, authenticated tests carried out earlier have proved that the claimed herein self-locking and self-tightening features are indeed attainable. Proposed related manufacturing processes and operation plans involving a combination of automated CNC high technology (Lasers) and CNC low technology (mechanical equipment, dies, tools, fixtures, etc.) may result in these high quality products produced at relatively reasonable cost.

Description

. ~ 2~~31G~1) THREADED AND NON-THREADED FASTENER IMPROVEMENTS
nrcrT.ncrrnF
(Specification) This invention .relates to value-added improvements to conventional commercial fasteners such as set screws, nuts and bolts and non-threaded fasteners such as spring pins (sliced pins). Said com-mercial fasteners are used to join parts or sub-assemblies of piping systems, of machinery, mechanical equipment, various structures, manufacturing plants, power plants, jet aircraft, ships, etc. For example, mechanical joints are gaining importance as bigger and bigger systems are designed and built to obtain the benefits of size economy. Examples include commercial jet planes, super oil tankers, even bigger power plants, oil platforms, etc.
Yet many systems must functionally include fixed and portable, .. - disconnectable and reconnectable joints at coupling points, some mechanical, some of a sealed type. They all use fasteners such as set screws, bolts, nuts, spring pins, etc. A loosened screw or bolt may cause chronic leaks or spillage of toxic fluids, while loosened or lost set screws may cause joined parts held by said screw to fly apart resulting in major and costly plant or equip-ment shut down or catastrophy. A set screw worth less than $1.00 may cause power plant shutdown and associated power loss amounting to $2,000,000 as has been reported in the media.
Installed and not locked set screws, bolts or nuts would stay tight provided a friction force between their internal and external threads is higher than the in-service force which tends to overcome said friction force. When the friction force is lower, a set screw, bolt or nut would get loose and possibly could get lost. This in-service force may be generated by in-service vibration, thermal cycling, working load fluctuation, contracting metals, flattening, etc. In order to obtain the needed friction force a proper fastener pre-load must be pro-vided by application of suitab~.e installation torque. It is difficult to arrive at a precise pre-load due to the varying conditions peculiar to a given connection. Consequently, in critical applications various conventional locking means are applied including cotter pins, locking wire, chemical resins, plastic inserts, etc. Such means have certain shortcomings.
For example, for locking wire cotter pin applications, a time-2~~.'32~i~ c2) consuming in-situ drilling of a small hole in normally hardened bolt is needed. This creates drilling chips which must be met-iculously collected to prevent contamination of adjacent, possibly Friction-sensitive parts or components. A11 these activities are prone to human error or neglect. Disassembly of resin-locked connections may also be time-consuming and hazardous because, frequently, a torch must be used to melt the resin. In the pro-cess, an adjacent plastic 0-ring or rubber seal may be damaged causing future system malfunction or shutdown. If no torch is used, a seized screw, bolt or nut must be removed by grinding or drilling operations. These operations are time-consuming and also create chip-hazards resulting in possible future failures.
These failures may affect safety, economy, reliability and environmentability of involved plants and equipment.
In addition, conventional fasteners don't offer any means to reveal if any unauthorized handling, tampering with or malpractice took place. Also, time-consuming and costly problems may be encountered when wooden joints are made involving conventional screws and nails. Unanticipated wood-splitting of parts may occur during their joining requiring unavoidable disassembly, replacement and re-assembly. Similarly, destruction of joined parts could take place when changes must be made to wooden parts erroneously nailed together. Frequently, to avoid splitting, thicker, heavier and costlier materials must be used.
Proposed fastener improvements were conceived to overcome such problems and enhance said aspects of economy, safety, reliability and environmentability of metallic, wooden and plastic joints.
First-generation of somewhat similar improvements, conceived earlier, refer to U.S. Pat. No. 3662804, Can. Pat. Nos. 893513 and 922550 have been tested. Refer to Report No. 2 by Ontario Research Foundation (described more fully in the reference section of the invention). 'Phe self-locking and self-tightening features were confirmed by said authenticated test.
Presently suggested improvements related to conventional set screws include ten new features described as follows:
1. Two or more locking teeth in lieu of one;
2. More than two times longer locking beam is more flexible, eliminating fatigue failure from excessively repeated bendings.

3. Undercut slit is greatly narrower thus increasing screw ~0631~~
strength.

4. Tapered side of the new beam cross-section was eliminated, also to increase beam strength.

5. Repeatable tooth sharpness would be assured by laser-cutting process.

6. Hardness of biting teeth would be assured and kept constant by hard chrome or electroless nickel plating. Such plating would also create needed and sustained tooth hardness of non-hardenable set screws made from austehitic steels.

7. Bend-out operation, to make teeth lock, would be fast and easy, done by end users themselves during field installation in lieu of previously factory-made bending. This would reduce manufacture costs and permit end users to adjust the degree of desired locking effect.

8. Single/multi-use feature was introduced permitting disclosure of any unauthorized handling, tampering with or malpractice of installed improved set screws.

9. New feature was added to eliminate unlocking by using pen knife or small screw driver.

10. A new unlocking tool was invented to satisfy feature as at 9 to improve the quality and reduce manufacture cost.

11. Novel spotting punches were invented to punch anchoring spots thus permitting installing torque of new set screws to anchor into them and reduce to near zero the value of installing torque.

12. Ultra short set screws with length equal to half screw diameter, still suitable to be locked, became possible be-cause of the feature as at 11.
Further proposed improvements comprise an invention of novel wing wood screws. It would include an assembly of conventional wood screws, turn buttons and spring pins manufactured in a unique way by combination of high and low technologies.
Still another improvement comprises a new shape of locking barb, laser cut at conventional spring pins. Such laser cutting may be undertaken at conventional hardened spring pins thus obviating their annealing, a costly operation which was needed to obtain earlier invented improvement. Refer to Can. Pat. No. 1045963.
Also, here proposed barbs of teeth would be longer, therefore more flexible, easier to install and would have greater axial retention. The sharpness of locking barbs would be enhanced by 206~1~4 c4~
either hard chrome or e:Lectroless nickel plating. Such plating would also assure their continuing sharpness.
Still another improvement comprises a nurnber of new processes to manufacture spring loaded nails. The manufacture would combine application of high and low technologies to create a new high quality product at the lowest possible cost. Such novel manufac-turing process was not described and not anticipated in the related Can. Pat. No. 1045963.
Still another improvement comprises novel nuts, hexagonal or square type, obtained by modification of conventional commercial nuts, Such improved nuts would be double locked, when installed, using said novel spring nails, two per each nut. A novel spotting punch, still another improvement, one common to all nut sizes, was invented to anchor spots for said nails. A novel clasping procedure, using a screw driver and hammer, was invented to assure said nails reliable retention, yet permitting their relatively easy removal when locked nut must be unlocked, joint disconnected and reconnected if required.
Still another improvement comprises invention of spotting punches, one for each size of said improved set screws, permitting great reduction of installing torques, normally required for the con-ventional set screw.
Still another improvement comprises a number of manufacturing processes and operation plans needed to ensure that proposed improvements could be fabricated to obtain highest quality, low-est reject rate and lowest possible cost.
In drawings which illustrate embodiments of the invention, Fig.
1 is an isometric view of a modified conventional set screw suitable for endless reuse if' its unlocking tool described further down is used, but impossible to remove by conventional key; Fig.
2 is the top plan view of Fig. l; Fig. l,A is as Fig. l, but suitable for a single use only if conventional key is used to unlock it or suitable for limitless re-use if said unlocking tool is used; Fig. 2A is the top plan view of Fig. lA; Fig. 3 is an isornetric view of said unlocking tool; Fig. 4 is the top plan view of proposed wing wood screw; Fig. 5 is its front plan view;
Fig. 6 is the front plan view c.f alternative end of Fig. 5;
Fig. 7 is the end plan view of Fig. 5; Fig. 8 is the right end plan view of Fig. 5; Fig. 9 is an isometric view of conventional commercial spring pin, modified as suggested by this invention, ~~63~.~'A (5) including the provision o:E t.wo locking barbs or teeth at one end only; Fig. lU is as Fig. 9 but showing said barbs provided, one pair at each end; Fig. 11 is an isometric view of proposed spring-loaded nail, obtained by suggested improvement of conven-tional spring pin; Fig. 12 is the perspective view of improved commercial conventional nut; Fig. 13 is an isometric view of proposed spotting punch applied to make anchoring spot at a bolt shown with installed improved nut as illustrated in Fig. 12;
Fig. 14 is the perspective view of said nut installed and locked by two nails, shown in Fig. 12; Fig. 15 is an isometric view of another spotting punch to be used to provide anchoring spots for screws as in Fig. 1 arid la; Fig. 16 is the top plan view as in Fig. 1, but showing locking teeth to be bent out or de-flected by the end users themselves; Fig. 17 is the top view as in Fig.lA, but showing locking teeth to be bent out also by the end users; Fig. 19 is the illustrated production plan l, describing how an improved set screw, shown in Fig. 1 and 2, may be manufactured; Fig. 20 is the illustrated description of pro-duction plan 2 related to Fig. lA and 2A; Fig. 21 is the illus-trated description of production plan 3 related to Fig. 3; Fig.
22 is the illustrated description of production plan 4 related to Fig. 4, 5, 6, 7 and 8; Fig. 23 is the continuation of Fig. 22;
Fig. 24 is the illustrated description of production plan 5 re-lated to Fig. 9 and 10; Fig. 25 is the continuation of Fig. 24;
Fig.26 is the illustrated description of production plan 6 =elated to Fig. 11; Fig. 27 is the illustrated description of production plan 7 related to Fig. 12, 13 and 14.
A typical improved set screw, shown in Fig. 1 and 2, comprises an axial slitll and radial slit 2, both may be made by Nd:YAG
laser beam. Axially oriented contour 3 to 9 may be shaped by a dedicated power-driven shaving die, computer numerically con-trolled (CNC). It would remove not needed metal from the top of said set screw as its punch reaches the bottom of said radial slit 2. In such a fashion a partly circular cantilever locking beam 12 would be formed.
The half-circularly shaped sections 5 and 8 would accept two needles 17, one each, shown in Fig. 3. They will be described further down. The set screw length may be as short as half of its diameter, while the shortest commercially sold set screw is equal to only 3/4 of its diameter. The shown hexagon socket is ~06~~,~~ c6~
typical but set screws with square sockets or other shapes may be improved as well. Ultra short improved set screws would still be functionally acceptable when installed with finger-felt, near zero installing torque, to bottom into anchoring spot provided by the novel spotting punch, made to fit each screw size point.
It is shown in Fig. 13 and will be described further down.
The radial slits 2 in Fig. 1, 2a in Fig. la may be laser cut to extend approximately 270° beginning at 3 in Fig. 2, 3A in Fig. 2A
and stopping at 10 in Fig. 2 and l0A in Fig. 2A, respectively.
The contour 3 to 9 of the floating cantilever locking beam, shown in Fig. 1 would permit unlimited re-use of said screw when it is deflected by said tool, shown in Fig. 3. It cannot be removed by conventional key. The key is expected to turn in its socket during a forcible removal, thus frustrating any unauthorized removal attempt. In order to assure this to happen , the locking teeth 4 and 7 would be designed to obtain the strongest possible form while still retaining their biting or locking capability.
To provide a double lock, said teeth would be bent out by the end users themselves to project, peripherally , by at least 0.010", as illustrated in Fig. 16. This projection may be adjusted in field to be more than 0.010". An initial projection of 0.010" can be easily created prior to said screw installation.
For this purpose one would need a hexagonal conventional key, a conventional hexagonal or square nut and one conventional set screw. The latter would be screwed into said nut leaving the top nut half empty to accept the improved screw. Subsequently, the conventional hexagonal key would be inserted as deep as the thickness 12 of the locking beam shown in Fig. 1 and turned either way to force said beam to bend out as shown in Fig. 16.
The subassembly of two set screws and the nut may be hand held in a conventional vise grip pliers. Additional bending may be accomplished by a screw driver.
Fig. lA and 2A show a single/multi-use improved set screw. The locking teeth would be bent out in the same fashion as described above with reference to Fig. 1 and 2. This would produce the initial projection of 0.010" illustrated in Fig. 17. The locking teeth 4B. and 7B, Fig.2A would curl back when such installed set screw is forcibly removed without authorization during tampering with or by malpractice. Such attempts will be disclosed by curled back teeth, .They would be purposely made weaker to p~rm;it it to occur.

(7) ~o~? 5 A limitless re-use of this set screw is also possible when the unlocking tool, Fig. 3, is applied. If no lock is desired, said screw, with curled back teeth, may be endlessly re-used as a :regular. or conventional set screw. Tests have shown that said curling back effect is feasible.
Fig. 3 illustrates said unlocking tool to be used to :remove installed set screws shown in Fig. 1 and la. It may be made to include conventional hexagonal key 13, modified to obtain round neck 16. It would be assembled with the handle 14 by crimping in its portion 15 facing said neck 16. The handle 14 would be pro-vided with two commercial thick needles 17, properly foreshortened and proper:Ly tapered at their ends. The cylindrical portion of said needles would be pushed into slightly tapered holes, one each, laser drilled in 14. This slight taper is automatically formed when holes are drilled by laser beam. A portion at each hole would be axially visible as illustrated in Fig. 3. The projecting tapered end of each needle will contact semi-circular sections and 8 of Fig. 2 or 5A and 8A of Fig. 2A, respectively. As the handle 14 is pushed in the needles would deflect the eantileve.red locking beam, 3 to 9, bending it to unlock the installed screw.
Simultaneously, a coupling effect will occur between said screw and tool. The holding force, holding them together, can be varied depending on the taper made at said needles 17. Such a feature would make it possible to provide a safe and reliable remote delivery, installation, locking, unlocking, pick-up, removal, repeated, re-installations and removals o:E said screws, if needed.
For each screw size one dedicated unlocking tool world be renu:ired.
For a better hand grip, a tap portion of handle 14 may be enlarged and knurled, as shown in Fig. 3.
Fig. 4 illustrates a top view plan of a novel wing wood screw.
It may be made by combining three conventional fasteners, namely, turn bottom 19, spring pin 20 and wood screw 21, all illustrated in Fig. 5, which is the front plan view of this invention. For some applications the end of 21 being sharp, as shown in Fig. 5, may be made to be half-round as denoted by 22 in Fig. 6. Fig. 7 and 8 illustrate bottom plan view and right side plan view of Fig. 5, respectively. For esthetics and more convenient hand grip the top portion of Fig. 5, including 19 and 20, may be molded-in using novel stone-like compound called DOT-AX~~ compound another invention of this inventor.

2~~~~'~~ c8~
Fig. 9 illustrates proposed modification to conventional spring pin comprising the provision of two anchoring teeth 23 and 24 fabricated at one end of said pin. They would point away from its end to make pin insertion easy, but removal hard. Conven-tional, non-hardened spring pins, such as those made from austenitic stainless steels, may be electroless nickel plated to ensure sharpness and increase hardness of anchoring teeth 23 and 24. End users would be instructed to flare out said teeth to assume shape :53 and 54 as illustrated in Fig. 18.
Flaring out operation may be simple and scan be executed during the installation of said pin. The pin would be partly inserted into its accepting hole, with 23 and 24 still visible. Subse-quently, a punch and hammer or screw driver may be used to flare out these teeth. More so for greater anchoring effect, less for a lesser effect.
Fig. 10 illustrates a similar pin but featuring two anchoring teeth 25 and 26 at one end and two anchoring teeth 27 and 28 provided at the other end. Both pairs of teeth point away from corresponding pin ends. Proposed modified spring pins may be used to hold metallic, plastic or wooden parts together. Their use has been found very helpful, especially in wooden structures, where some temporary pre-assembly may be necessary or disassembly may be attempted to accomodate re-arrangement or to correct errors. Disassembled parts may be re-used because no destruction or splitting occurs either during assembly or disassembly. Be-cause of this non-splitting feature, lighter cross-sections and less costly lumber may be successfully used. To enhance retention of joined parts, pins may be coated with said DOT-A~~~ compound.
Also, said compound was found useful to "weld" such wooden joints thus increasing stil~.further the strength of such connections.
The first generation of somewhat similarly improved spring pan screws was earlier tested, refer to Report No. TOS1-85, AECL, Sheridan Park, Ontario. The test has disclosed that improved conventional spring pins would increase their axial retention by a factor of 4 maximum. The present improvement is expected to perform even better and cost less to fabricate. For example, previously costly annealing operation, needed to carry out on commercial hardened spring pins, to have their teeth cut con-ventionally would be eliminated. A less costly laser-cutting operation, possible on hardened spring pins, would be applied.

20~~1~'~ (9) Also, non-hardened commercial spring pins, made from austenitic stainless steels, would be made for effective locking once their laser- cut teeth would be electroless nickel plated. Such a plating would increase tooth hardness and sharpness. Without such plating, no hardness differential, of at least 10 points on Rockwell scale, would be created and self-locking principle would not work on improved conventional spring pins, made from non-hard-enable austenitic stainless steels.
Fig. 11 illustrates another improved spring pin. The improvement would be made on conventional commercial spring pins by adding two locking or anchoring teeth or barbs 29 and 3U at one end and flanges 31 and 32 at the other end. The barbs or teeth 29 and 30 would be flared out at installation by end users themselves, similar to the procedure described as related to Fig. 18. Also, an electroless nickel plating operation would be applied for nails made from austenitic stainless steel.
Improved spring pins as in Fig. 9, l0 and 18 and nails as in Fig. 11 were disclosed in different configurations in my related Can. Pat. No. 1045963. I feel that more than one novel feature was added in the herein described improvements to claim novelty.
For example, presently proposed self-locking teeth would be long-er, deeper, cut from the pin body, more flexible, there would be pairs of teeth provided, one at each end, a feature not disclosed in said patent, the flange would consist of two distinct halves which would be less costly to manufacture, there would be no locks or teeth earlier suggested at the pin back, the above mentioned annealing operation would be eliminated to reduce production cost, the electroless nickel plating, not previously anticipated, is herewith introduced to make an improved spring pin made from austenitic steel, to work, suggested novel spotting punch, appli-cable for herein disclosed nails, was not then anticipated and finally, a suggestion to use a proprietary DOT-AX°° stone-like compound, to make joints stronger, was not then anticipated.
Fig. 12 illustrates still another improvement to conventional commercial hexagonal (as shown) or square nuts (not shown).
This improvement comprises the provision of two groups of grooves cut centrally at nut top end, each group located at one hole side. Each group consists of centre deeper groove 33 with half-cylindrical bottom and continuing identical groove 34 located opposite the nut hole. The groove 33 would have adjacent shallower ~O~J~~~ ~lU) groove 35 located at its one side and identical groove 36 located at the other side of said groove 33. Both shallower grooves 35 and 36 would have flat bottoms and thin walls 39 and 40 facing said groove 33. Identical arrangement would be pro-vided at the opposite end of nut hole with corresponding deeper groove 34, adjacent shallower grooves 37 and 38 and respective thin walls 41 and 42, j Fig. 13 illustrates a novel spotting punch which will fit said deeper grooves and would be used to punch anchoring holes, one at each side of bolt 44, forming part of a joint and.accegting i the said improved nut, as shown in Fig. 12. The punch contour would be made to fit the end of the nail shown in Fig. 11. To lock said nut in place two of said nails would be hammered in, one at each bolt side, as illustrated in Fig. 14. To ensure their retention, said thin walls 39 and 40 and 41 and 42 would be clasped in to arch tightly over said installed nails 45 and 46.
By design, a slit would be retained between said clasped walls to permit a quality inspector to see if locking nails were ad-equatly pushed in to anchor with said bolt. Also, marks from a screw driver or chisel, to be used when these nails must be pushed out, to permit unscrewing of said nut, would disclose any removal attempt, authorized or unauthorized, any tampering with or malpractice. Said improved nuts are suitable for endless re-use, while preferably, new nails should be used each time said nuts are unscrewed, rescrewed and relocked. Preferably, said nails would be pushed in with a hammer with their barbs or lock-ing teeth facing half-circular bottoms of deeper grooves 33 and 34 shown in Fig. 12. A screw driver and hammer may be used to carry out said clasping operation. To unlock said nut, before its planned removal, said screw driver, chisel and hammer may be used to push out said nails. Also, said slit may be used to push out said nails using a conventional punch and hammer in the case nail flange is broken off inadvertently.
Improved nut locking arrangement illustrated in Fig. 14 may be used to assure predictable safety, economy and reliability of involved joint. Benefits are offered by omission of drilling operation, normally required on site, to lock a conventional nut by locking wire or cotter pin. Associated drilling chips, time-consuming drilling of small hole in a hardened bolt .causing possible bit breakage, time-consuming, possibly incomplete collection of (11) said chips, all would be eliminated if proposed improvement is implemented. In addition, the involved bolt won't be weakened by a hole because the two small anchoring spots would not adversely affect its strength.
Fig. 15 illustrates a spotting punch which would be similar in design to punch 43, shown in Fig. 13, except it would have a longer stem 47 and would be made in different sizes to fit one of each set screw sizes, such as illustrated in Fig. 1 and lA.
It's end 48 would be made to fit each cup point of corresponding set screw. The longer stem length 47 may be required when an-choring spot for longer set screws must be made as said punch is pushed into internally threaded hole accepting said longer set screw. Both punch types, one shown in Fig. 13 and one shown in Fig. 15 may be made by modification of commercial punches exhibiting conventional design of their portions denoted by 49, 50 and 51.
Fig. 19 shows illustrated operation plan 1 related to Fig. 1 and 2. It lists possible but not exclusive manufacturing process involving high and low technologies which may be used to assure the highest quality of product at the lowest possible cost.
Fig. 20 shows a similar illustrated production plan 2, but re-lated to Fig. lA and 2A.
Fig. 21 shows an illustrated production plan 3.
Fig. 22 and 23 show illustrated production plan 4 related to Fig. 4, 5, 6, 7 and 8.
Fig. 24 and 25 show illustrated production plan 5, related to Fig. 9 and 10.
Fig. 26 shows illustrated production plan 6 related to Fig. 11.
It suggests the use of laser beams not only to cut locking teeth, but also to heat up said pin flange to facilitate its forming.
Other production plans may comprise CNC induction coil integrated into automated process.
Finally, Fig. 27 shows an illustrated operation plan 7, related to Fd,g.:~12,13&14 to modify conventional nuts to acquire said improve-ment. Alternative production plans may include groove cutting, employing multi-lasers or co-forming said grooves while conven-tional nuts are manufactured.
Enumerated production plans may include deviations, inevitably to occur during implementations. They should not, however, impair exclusive property or privilege of present invention.

~~6~1~4 (12) o~: c~oFnTr~c U. S. Patent No. 3662804 Can. Patent No. 893513 Can. Patent No. 922,550 Can. Patent No. 1045963 U.S. Patent Disclosure Document ~~153798 U.S. Patent Disclosure Document 4192882 s U.S. Patent Disclosure Document 4193453 U.S. Patent Disclosure Document 1257265 U.S. Patent Disclosure Document 44266743 U.S. Patent Disclosure Document ~~296530 U.S. Patent Disclosure Document 4296531 Can. Trade Mart Journal, November 21, 1990 Application for Extension of DOT-AX Trade Mark Can. TM 250,851 (1991), Certificate of Amendment of DOT-AX Trade Mark Report No. 2, Vibration Test on Self-Locking (SEL) Fasteners, Proposal No. P430-ICD, for Atomic Energy of Canada Ltd. (AECL) Sheridan Park, Ontario, by Ontario Research Foundation. SEL
fasteners tightened by amount up to 540° (installed in floating position).
Report No. TOS1-85, AECL, Sheridan Park, Ontario.
Initial Test on Improved Spring Pins.
The improved feature has increased axial retention of conventional spring pins four times, maximum.
Leo L. Krywitsky c The mentor, Yule Avenue, Toronto, Ontario.
M6S 1E8, Canada Phone 416/767-6395

Claims (5)

1. Two or more self locking and self tightening in critical applications, metallic teeth, integral with or prmanently connected to the top of commercial hexagonal set screws, metallic inserts used in commercial electric wire connectors and commercial nuts, formed as resilient flat curved cantilever with 3/16" thick maximum, with each tooth free end narrowing to include a sharp vertical edge and vertical axial groove with semi-circular bottom with the tooth located nearly of the outside of cantilever curved line, widening towards its fixed end, with its free end projecting a minimum of 0.10" outwardly, beyond the said screw or metallic insert outside diameters or inwardly, beyond the said nut thread minor diameter, with said groove arranged near its locking free edge but located at the said inside of its curved line, with said teeth arranged in symmetric pairs to permit an easy screwing in of said improved fasteners but apposing their removal, with two or more similarly shaped teeth located at the bottom of improved wood screws equipped with integral or permanently attached handles.

2. As in claim 1, but including technically connected spotting punch, as an essential part of this invention, made by modification of a suitable commercial punch to obtain an elongated cylindrical stem to fit freely with the threaded hole accepting said improved set screw, with sharp circular edge arranged at the bottom of said stem, including a shallow recess in depth of 1/32" maximum, with said punch to be used to make circular anchoring indentation to provide a predictable and reliable keying effect when said improved set screws is screwed in to bottom into it.

3. As in claim 1, but including a technically connected notching punch, an important part of this invention, made by modification of suitable commercial punch to obtain an elongated cylindrical stem of the same diameter as claimed in a similar dependent claim 2 but the stem end is provided with a plurality of fine-pitched axial ridges of triangular cross-section each, about 1/4" long, with a sharp circular wedge, about 1/32" deep, provided at the stem end, said punch to be used to cut axial notches, two or more, about 0.1." deep, at internal threads of holes into which said improved set screws and metallic inserts would be screwed in or at a bolt thread, after said improved nut is installed, with said notch providing anchoring grooves into which released resilient locking teeth would spring in as the installing tools, claimed in dependant claims 4 and 5, are removed.

4. As in claim 1 but including dedicated tools, as an important, technically connected part of this invention, to be used to install, lock, unlock and remove said set screws and metallic inserts, comprising a metallic round rod to fit freely into the hexagonal socket of said set screw or into the central hole at said metallic insert, one end of said rod bent 90 degrees to serve as a handle, the other end to receive a press fitted or silver brazed metallic disc of its thickness equal to said rod diameter, minimum, located away from the end rod by a distance equal to rod diameter, minimum, with two or more axial press-fitted or silver brazed pins with said disc, opposite located, arranged to control deflection of said locking teeth, during installation or removal of said set screws and metallic inserts, preventing development of permanent set of said teeth, by means of tapered end, provided at each pin, arranged at the pin portion projecting below the of said disc installing end, with two or more axial grooves with semi-circular bottom each, arraanged at the disc, to serve as guides for said notching punch, as claimed in claim 3, said grooves having depth such as to assure that said inserted punch would project a minimum of 0.10" beyond tool disc outside diameter, to cut the locking notches, with said grooves location assuring provision of two or more anchoring notches, required to guarantee the automatic self locking and self tightening features provided by the corresponding teeth, claimed in the claim 1.

5. As in claim 1, but including commercial wrench socket daptors, modified to contain two or more axial press-fitted or silver-brazed pins with their tapered ends, projecting below said adaptor inner bottom, suitably formed and located to control and prevent permanent bending of said self locking and self tightening teeth as claimed in claim 1, with two or more axial holes, located suitably near said pins to serve as guides for said notching punch, claimed in the dependant claim 4, to be used to cut anchoring notches at the involved bolt threads receiving installed said improved nut, to guarantee automatic self locking, self tightening features, similar to claimed in claims 1 and 4.