RU2409771C2 - Holding system with weak crimping load (versions) and procedure for installation of holding device of crimping type by means of holding system with weak crimping load (versions) - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: holding device consists of element of pin with elongated body. An enlarged head at one end of the pin engages one side of parts. A grooved section of the pin protracts beyond boundaries of the opposite side of parts. A yoke consists of a section of a body fit for crimping in locking grooves of the pin in response to relative axial crimping load applied with a seat member. The yoke is strengthened and does not require thermal treatment; it facilitates optimal combination of reduced thickness of the yoke body and increased rigidity, thus minimising crimping load. For locking grooves of the pin there is made a profile of thread with a weak crimping load. Here there are also disclosed procedures of installation of holding device of crimping type by means of holding system with a weak crimping load.

EFFECT: high strength of connection and simplicity of assembly.

26 cl, 13 dwg

Description

FIELD OF THE INVENTION

The present invention relates to fastening means and, more specifically, to a fastening system comprising a crimp type integral fastening means and therefore a crimping tool that exhibits an optimal ratio of low crimp load and high strength. The invention also relates to a simplified installation method using a fastening system with a low crimp load.

State of the art

In many commercial applications, two-part threaded or crimp fasteners, often called fastening bolts, are often used to hold together a number of parts together. See, for example, US Pat. Nos. 2,531,048; 3215024; 3,951,053; 4,472,096; and 5090852. Material properties (for example, but not limited to tensile strength and stiffness) of these fasteners vary depending on the commercial application in which the fasteners will be used. To distinguish the changing properties of fasteners, fasteners are usually referred to as Standards. The fastener standard is an indicator of its strength. Industry standards set the required strength of a particular fastener for

compliance with a specific Standard, wherein the strength of a particular fastener is determined by the strength of the material of the bolt or

pin mounting hardware. For example, the diameter of the pin or bolt of the fastening means of the body portion into _^1/2-inch Standard 5 is% inch for use in the hole parts with a nominal diameter of _^1/2 inch, and, according to SAE J429, Standard 5 or ASTM A-325, such a fastening Standard 5 should have a minimum tensile strength of 120 ksi. In comparison, the fastener must have a minimum tensile strength of 150 ksi so that it can be called the fastener of Standard 8. The fasteners of Standard 5 are often used, for example, for railway applications (for example, for railway cars). Standard 8 fasteners are commonly used in commercial applications, such as fastening truck components for commercial transportation.

Conventional crimp type fasteners include a pin and a clamp. Most of these fasteners are tightening fasteners and include a pin body with a locking portion having locking grooves and a tightening portion having tightening grooves. Tightening grooves are adapted for gripping with special teeth in the clamping cams of the installation tool with a crimping anvil. The crimping anvil is made with the possibility of adhesion to the clamp and the application of relative axial force between the pin and the clamp, as well as movement over the clamp and its compression in locking grooves. The relative axial force comprises a combination of tensile load on the pin caused by the clamping jaws and compressive load on the clamp caused by the crimp anvil. An addictive section of several crimping type fasteners is connected to a section of locking grooves with a dangerous groove of reduced strength. The dangerous groove is adapted to tear at a given value of the axial or tensile force, which is greater than the force required to crimp the clamp. Therefore, the tightening portion or tail of the pin will be separated and removed from the body of the pin after crimping is completed. Other crimp fasteners, however, have tightening portions that remain on the pin after installation is complete. See, for example, US patents No. 5315755, 5548889 and 5604968 (revealing a threaded tightening section that does not separate from the pin). In other words, these fasteners do not have a pin tail. See, for example, FIGS. 1-8 of the '755 patent.

Among the problems often encountered when using crimp type fasteners with relatively high strength (e.g., Standard 5 or higher), there is the problem of the excessive amount of applied tensile load required to fully crimp the clamp. This leads to premature wear of the installation tool, in particular the tightening mechanism, as well as to the erasure of the tightening grooves on the pin. The high crimp load, in general, also complicates the installation process, especially when using manually operated installation tools. While trying to overcome some of these shortcomings, many different changes to the installation tool were made. For example, U.S. Patent No. 4,299,519, which is incorporated herein by reference in its entirety, discloses a claw-shaped pin section of the pin and an appropriately shaped tool gripping structure that are designed to engage all of the tightening grooves of the tightening section with a gripping tool structure, thereby preventing erasure tightening grooves. See for example. Figure 1-5 of the patent '519. Other tools include only hydraulic and / or pneumatic piston cylinders to assist in applying the necessary crimping force. See, for example, US Pat. Nos. 4,597,2663 and 4,878,373. However, this increases the size and weight of the tool, which may make it difficult to operate or limit its availability, thereby potentially jeopardizing its precise use when operating the fastener and thus The quality of the final installation. Therefore, it is possible to improve the installation tool and method for crimping type fastener systems.

The high crimp load is mainly the result of the use of clamps of fasteners that have an increased wall thickness and which, therefore, have a structure that overflows or exceeds the thickness of the locking grooves to achieve the required strength for a particular Standard of fastening means (for example, Standard 5 and Standard 8 ) See, for example, US Pat. No. 5,090,852, as described above, (disclosing a modified pin thread profile for incorporating shallow grooves and a streamlined thread profile contour, the clamp having an increased wall thickness with enough material to exceed the depth of such shallow grooves to achieve the required strength to cut); see also the '755 patent, as mentioned above, and US patents 5548889 and 5604968 (disclosing the design of shallow grooves of a pin and the body of a collar, the volume of which has at least 16% excess material to exceed the depth of the grooves). Exceeding the depth of the locking grooves is problematic. This is the primary source of the aforementioned undesirable excessively high crimp load. Consequently, several attempts have been made to counteract these drawbacks and, in particular, to an excessively high crimp load, by changing the design of the crimp type fastening means.

For example, US Pat. Nos. 6,233,802 and 6,497,024, which are incorporated herein by reference in their entireties, disclose a fastener system for a two-part crimp type fastener having a wide, shallow thread profile of the locking groove, the design of which allows fastener to be installed with low crimp load, unlike traditional crimp type fasteners of a comparable Standard, while still retaining essentially the same physical properties (e.g. tensile strength ny; design load) during installation. A weaker crimp load allows the preferred use of a smaller, lighter installation tool. The system is described when applied to fastening means having pin tails, as well as to fastening means not having pin tails. The invention is set forth to facilitate the adhesion of smaller threads in a tightening section, since the excessive force required to break a dangerous groove is not required for tightening crimping fasteners having threaded tightening sections that do not separate, as in the '755 patent, as mentioned above. This, firstly, leads to lower pressure on the engaged thread of the corresponding threaded sleeve or nut element of the tightening tool, thereby increasing the tool life; secondly, it allows the use of a shorter, less expensive pin, since it requires a smaller protrusion of the pin to capture a reduced number of tightening grooves that must be caught; thirdly, it allows the use of installation tools of smaller sizes and therefore lighter and less expensive, since the final installation requires less applied load. The system also facilitates the use of an internal drive unit. See for example. 17 and 18 of the '755 patent (illustrating an internal drive device including a tightening threaded rod or spindle engaged with tightening grooves of the threaded barrel at the end of the pin body). As described in the '755 patent and US patents nos. 5548889 and 5604968, which are incorporated herein by reference in their entirety, the use of such an internal drive device involves reducing the protrusion relative to the external drive device, which, in turn, provides a more efficient installation and the appearance of the fastening means.

However, as disclosed in the '024 patent, as mentioned above, in order to achieve the above advantages, it was necessary to change the thread profile (for example, the structure of the locking grooves) to a wider and shallow configuration. Although changing the thread profile is a viable sign to reduce the crimp load, the thread disclosed later in the '024 patent is a fundamental change requiring a significantly larger thread pitch and many different roundings with relatively sudden and intermittent transitions between roundings (for example, from one rounding to another ) The manufacture of pins with an open thread profile is therefore complex and expensive. Additionally, the intermittent transition between the curvatures of the thread profile prevents the maximization of the welcome engagement of the thread profile with the grooves of the clamp when crimping the fastener. Therefore, there is also the possibility of further improving the thread profile for the locking grooves of the pin.

Additionally, clamps of the type disclosed in the '802 and' 024 patents have a very narrow range of acceptable stiffness, since too much stiffness leads to an extremely high crimp load and too little stiffness has insufficient strength. Specifically, this is problematic with respect to fasteners of higher Standards (eg, Standard 5 and above), for which an increase in stiffness and bolt and clamp is necessary to meet industry requirements for tensile strength. Therefore, the known clamps must be heat treated to be soft enough to crimp and be compatible with a modified thread profile, but strong enough to comply with industry Standards. This further increases the cost and complexity of manufacturing fasteners. For example, two such heat treatment methods include stress relieving and quenching and quenching; obtaining the constant required rigidity by stress relieving is very difficult to perform, and rapid cooling and hardening is expensive and difficult to perform without undesired carburization or decarburization of the surface of the clamps. Both methods are time consuming and expensive, requiring, for example, additional costs for the operation of the furnace.

Therefore, it is highly desirable to provide a high-strength, fastening system with a low crimp load, which, among other features, has all the advantages of low-crimping fasteners disclosed in the patents '519,' 755, '802 and' 024, as mentioned above, but which also does not require, for example, significant costs and time for thermal processing of the clamp.

Therefore, there is a possibility of improvement in the field of technology regarding high-strength, fastening systems with low crimp loading.

Disclosure of invention

An object of the present invention is to provide crimp type fasteners that exhibit an optimal combination of reduced crimp load and high strength.

Another objective of the present invention is the provision of fastening means using a hardened clamp that does not need to be heat treated (for example, by quenching and quenching; stress relieving).

Another objective of the present invention is the provision of a high-strength clamp with a reduced wall thickness, due to which, therefore, the weight and crimp load are reduced, but strength is maintained.

An additional object of the present invention is to provide a hardened collar having sufficient physical properties (e.g., stiffness; strength) to meet the required Standard of fastening means (e.g., Standard 5; Standard 8).

Another objective of the invention is the provision of a clamp that can be used with existing fasteners and their thread profile, but which has the required strength of the desired Standard (for example, Standard 5; Standard 8, but not limited to).

Another object of the invention is to reduce the crimp load necessary to install the fastening means, thereby reducing wear of the components of the installation tool (e.g., crimping anvil; couplings; half-shells, but not limited to them) and increasing the service life of the tool.

Another another objective of the present invention is the provision of fastening means, which eliminates the steps of expensive heat treatment (for example, stress relief; rapid cooling and hardening) of the clamp of the fastening means.

Yet another object of the present invention is to provide a collar applicable to a wide variety of crimp type fasteners, which specifically include, but are not limited to, fasteners with a pin tail and fasteners without a pin tail, such fasteners being new or part of existing stock for which the clamp is being upgraded.

Another objective of the present invention is to increase the stiffness of the clamp to maintain or improve the strength level of the clamp, but to reduce the crimp load by not exceeding the depth of the locking grooves of the pin of the fastening means.

An additional object of the invention is the provision of an improved thread profile of the locking grooves of the fastening means, designed to overcome the disadvantages of the known shallow or wavy thread profiles.

Another object of the invention is to provide a thread profile of the locking groove, the structure of which reduces the crimp load and which is relatively easy and thus economical to do.

Another another objective of the invention is to provide an appropriate traction groove and configuration of the gripping structure of the tool, which provides, among other advantages, one or more advantages in improving the adhesion between the gripping grooves and the gripping structure, increasing the fatigue life of the gripping structure (for example, couplings), for example, decreasing the diameter of the tightening portion of the pin and increasing the cross section of the coupling and thus the thickness and strength of the tightening thread, and the minimum length of the protrusion of the tightening section of the pin.

Therefore, it is a general object of the present invention to provide an improved, high-strength crimp type fastener and its reinforced clamp that can be installed with a reduced crimp load using existing tools and which exhibit optimal material properties (e.g., stiffness; strength) of the required Standard fastener, and providing a fastening system with a low crimp load containing one or more hardened clamps, improved tightening piece FTA and configuration of the installation tool and a better profile of the thread of the fastening means.

These and other objectives are consistent with the present invention, which provides a fastening system and method with a low crimp load.

In one embodiment of the invention, the fastening means of the system may include a collar having increased stiffness and reduced wall thickness of the collar, which avoids exceeding the depth of the locking grooves. The clamp can be very economically produced and easily crimped in comparison with the known fasteners of a comparable Standard. This is the result of using the already hardened clamp of the present invention, thereby eliminating the required expensive heat treatment (e.g., quenching and quenching; stress relieving). Also, no change in the clamp is required to match the thread profile of the locking groove of the pin. Therefore, it can be easily used with existing pins and installation tools having many different thread profiles of the locking groove, and its reduced crimping load, which is characteristic of its thin wall, increases the service life of the installation tool and / or allows the use of lighter tools. The fastener and its collar of the present invention have all of the above advantages, while additionally providing improved and unexpectedly high strength characteristics sufficient to comply with Standard 5 and Standard 8 of industry standards for fasteners.

Therefore, the fastening system with a low crimp load is designed for crimp type fasteners designed to hold together multiple parts. The crimping type fastening means includes a pin member having an elongated pin body configured to be located in the holes of the parts in the same line. The pin element at one end ends on an enlarged head adapted to adhere to the surface on one side of the parts, and on its opposite side ends on a furrowed portion that can extend beyond the opposite surface on the opposite side of the parts. The grooved portion of the pin comprises a locking portion having a plurality of locking grooves that define circumferential grooves of the pin and associated pin shoulders ending at the tops of the pin.

The fastening means may be selected from the group consisting of fastening means with a pin tail and fastening means without a pin tail. The furrowed portion of the pin of the fastening means may not have a pin tail and includes an internal threaded channel, wherein the mounting tool includes an internal drive device adapted to engage by threading with the internal channel during crimping of the fastening means.

In another embodiment of the invention, the low crimp fastening system includes a pin having a substantially straight pulling portion that extends from a second end of the pin and includes a plurality of pulling grooves. The tightening portion has an outer diameter that is smaller than the outer diameter of the locking portion of the pin. The corresponding installation tool has a collet with a tightening region for welcoming engagement with the tightening grooves of the tightening section. The protrusion length of the tightening portion from the end of the pin is relatively short. Consequently, the tightening portion may remain on the pin after crimping, or may be removed by shaving or tearing a dangerous groove that may be provided on the pin. The reduced diameter of the tightening section allows the use of thicker and more durable installation tools. The strength of the tightening section provides improved traction with the installation tool.

The diameter of the first tooth of the tightening region of the installation tool may be greater than the remainder of the tooth of the tool, which increases the tool life. The tool can be further improved, and the crimp load is further reduced by the inclusion of a relatively small crimp load.

In yet another embodiment of a fastening system with a low crimp load, the pin of the fastening means may include a thread profile, which is determined by a number of smoothly conjugated roundings having a substantially smooth transition between all rounds of the grooves of the thread profile. Due to this, the adhesion of the grooves of the clamp during crimping is improved. Such a thread profile eliminates the complexity of the thread rolling dies used for thread rolling.

In another aspect of the disclosure, there is a fastener system with a low crimp load for a crimp type fastener designed to hold together multiple parts. The crimping type fastening means includes a pin member having an elongated pin body that is adapted to be located in the same holes in the parts. The pin element at one end ends on an enlarged head adapted to adhere to the surface on one side of the parts, and on its opposite side ends on a furrowed portion that is able to extend beyond the opposite surface on the opposite side of the parts.

The groove portion comprises a locking portion having a plurality of locking grooves that define pin grooves extending around the circumference and associated pin shoulders ending at the tips of the pin.

The installation tool includes an anvil element with a crimp cavity. There is a reinforced collar that includes a generally straight clamp body that must be crimped in said locking grooves on said pin element in response to relative axial force or crimp load applied between said pin element and said reinforced collar with said mounting tool.

The required clamp load on the parts to be bonded together forms a bonded joint. The structure of the crimp cavity of the said installation tool is made for coupling with the said body of the clamp and its compression radially inward. When crimped, the hardened clamp has grooves and shoulders of the clamp that engage with the grooves and shoulders of the pin. The pin element and said hardened clamp are made of various materials, the shear strengths of which are of different sizes, in order to avoid essentially plastic deformation of said pin element when crimping the said clamp with the said pin element.

The collet has a protrusion from said collet, which increases the length of the draw section in the direction of the clamp, thereby increasing the contact area with the mentioned anvil.

The reinforced clamp does not require heat treatment, and the straight, in general, body of the clamp of said reinforced clamp has a wall thickness that is relatively thin, which reduces the crimp load required for said reinforced clamp.

The protrusion forms a flat circular front surface in front of and adjacent to the leading thread of the collet, and then a circular forward inclined front surface in front of the flat front surface, and a second flat front surface, and an angular flat front surface behind the line of intersection with the outer diameter of the collet.

The end of the rod does not slide to the position of the diameter, which is in line with the base of the groove, which increases the tensile strength when shifting the top of the end of the rod.

In yet another aspect, the last peak of the thrust has a contour corresponding to the increased radius of the tightening device of the last tooth of the collet.

All of the aforementioned low crimp mechanisms can be used individually or in any suitable combination. Crimp type fasteners and a method for securing together multiple parts using the aforementioned low crimp system are also disclosed.

Brief Description of the Drawings

A full understanding of the invention can be obtained from the following description of preferred embodiments when read along with the accompanying drawings, in which:

Figure 1 is a cross-section of a fastening system with a low crimp load and its reinforced clamp according to an embodiment of the invention used for crimping type fastening means having a pin that includes a removable pin tail, and showing fastening means inserted into holes located in the same line in two parts, before crimping with a setting tool, which is partially shown.

FIG. 2 is a cross-section of a fastening system with a low crimp load and a hardened clamp in FIG. 1, used for crimping type fastening means that does not have a pin tail, and showing fastening means after crimping with an installation tool for fastening two parts together.

FIG. 3 is a cross-section of a fastening system with a low crimp load and the reinforced clamp of FIG. 1 used for crimping type fastening means without a pin tail, before being crimped with a setting tool having an internal drive device according to another embodiment of the present invention.

4 is a plan view of a collar for crimp type fastening means according to the prior art, wherein the inner channel of the collar is shown by an invisible line.

FIG. 5 is an isometric view of the reinforced collar of FIGS. 1-3, which has a reduced wall thickness according to an embodiment of the present invention, wherein the portion of the collar is cut to simplify illustration.

6A, 6B and 6C are cross-sections of samples of crimped fasteners having a wavy, deep and hybrid thread profile of the locking groove, respectively.

Fig. 7 is a sectional view of an improved tightening portion of a fastener pin and depicts configurations of a mounting tool according to an embodiment of the invention and four successive installation steps for crimping a clamp of a fastening means using an improved tightening portion of a pin;

Fig is a cross section of the final section of the collet for the installation tool in Fig.7.

Fig.9 is a cross section of the anvil element in Fig.7.

Fig. 10 is a sectional view of an improved fastening portion of a fastener pin and depicts configurations of a mounting tool according to an embodiment of the invention and four successive installation steps for crimping a clamp of a fastening means using an improved tightening portion of a pin using various collets.

11 is a sectional view of an end portion of various collets for the installation tool of FIG. 10.

The implementation of the invention

The main phrases used here, such as upper, lower, front, back, etc. relate to the orientation of the elements shown in the drawings and do not limit the claims.

As used herein, the term “multiple” refers to one or more than one (eg, multiple).

As used herein, the term “hardened” means a collar that has undergone strain hardening, for example, cold working, rather than a change in strength using a thermal process (eg, quenching and quenching / stress relieving). The clamps of the present invention exhibit high strength (e.g., Standard 5 or Standard 8) without requiring heat treatment.

The phrase “low crimp load” as used herein is used for comparison to describe a reduction in the required crimp load that is provided by features (for example, a reinforced collar; a tightening portion of a pin tail of a reduced diameter; an altered thread profile) of the fastening system of the present invention compared to known fastening means of a similar Standard. Representative examples of such a light or reduced crimp load are defined here in the tables and the corresponding disclosure.

Similarly, the phrase “reduced wall thickness” as used herein is used for comparison to describe the finer wall structure of the collar of the present invention compared to clamps of known fasteners of the same Standard. For example, the reduced wall thickness of an exemplary clamp has a smaller volume of material, and thus its structure is not designed to exceed the depth of the locking grooves, unlike many known fastening means.

As used herein, the term “tightening section” refers to an exemplary tightening section of the pin of the fastening means and a welcome tightening section of the setting tool for engaging with the above tightening section. As will be discussed here, an exemplary configuration of the draw-in portion comprises a substantially straight, reduced diameter parallel to the lateral draw-in section that protrudes a smaller distance from the end of the pin section with the locking groove than, for example, a conical draw-in drawback and welcome a portion of a tool according to US Pat. No. 4,299,519, which is incorporated into this application.

The phrase “thread profile” as used herein means an exemplary improved thread profile of a locking groove of a pin according to the invention. The new thread profile is hybrid since, among other features, the thread profile is partly a hybrid of certain features of different thread profiles. However, it will be understood that various tests and experiments were required to develop an exemplary hybrid thread profile and achieve its respective inherent advantages.

Although examples of fasteners of the present invention are defined with reference to certain specific dimensions, i.e. nominal diameters, general principles can be easily expanded to fasteners with a wide range of sizes (for example, diameters; lengths).

As shown in FIGS. 1-3 and 7, the present invention relates to multi-component (for example, having a pin and a clamp) fasteners of the crimp type, such as, for example, fasteners shown and described in the patent '024, as mentioned above, which incorporated into this application by reference. In FIGS. 1-3, 6B, 6C and 7, comparable components of the fastening means are equally numbered on each of the figures, but include different designations by the letters “a” (FIG. 2), “b” (FIG. 3), “c” ( 6B) and “d” (FIGS. 6C and 7) and can be considered substantially the same until the opposite case has been described. The use of the first feature of an exemplary fastener system 50 with a low crimp load, a reinforced clamp 14, is shown for each fastener 10, 10a, 10b, 10c and 10d in Figures 1, 2 and 3, 6B, 6C and 7, respectively.

FIG. 1 shows a fastening means 10 including a pin member 12 with a pin tail 41 and a reinforced clamp 14 with a low crimp load of the present invention. The pin element 12 has an elongated body 15, which extends through the holes or channels 16 and 17 located on the same line in a pair of parts 18, 20, respectively, which must be fastened together. The enlarged protruding head 22 at one end of the body 15 engages with the rear surface 23 of the part 18. The body 15 has a straight smooth cylindrical body section 24 adjacent to the head 22, which is arranged to fit into channels 16 and 17 located on the same line when landing with guaranteed clearance. Nevertheless, it will be understood that in some installations, the straight section of the body 24 may have a size that allows landing with high accuracy requirements or with an interference fit in one or both channels 16 and 17. The locking body section 25, having many circumferential circumferential locking grooves 26 is adjacent and integral with the straight section 24 of the body.

The fastening means 10 of FIG. 1, as discussed previously, includes a pin tail or body pulling portion 41 having a straight annular pad 42, followed by a plurality of annular pulling grooves 44. A hazardous groove 40 having a reduced inner diameter is located between the locking section 25 and the annular platform 42 of the tightening section 41 and defines the weakest area on the body 15 of the pin. The draw section 41, including the pad 42 and the draw grooves 44, has a reduced diameter Da with respect to the diameter Db of the vertices 71 of the lock grooves 26 of the lock section 25. The diameter Db is also equal to the diameter of the straight section 24 of the body. It will be understood, however, that in applications involving a landing with high accuracy requirements or a tight fit (not shown) in channels 16 and 17, the tops 71 of the locking grooves 26 will have a smaller diameter (not shown) than the diameter of the straight plot 24 of the body. Tightening grooves 44 are adapted to be gripped by a setting tool 100, which is used to install the fastening means 10 in the manner shown and described in the '024 patent, as described above.

The tools 100 required to install (eg, crimp) the clamp 14 may, in general, be constructed by a person skilled in the art and, therefore, only partially shown for simplicity. In short, the tool 100 has a nose assembly 102 with a plurality of circumferential clips 104 adapted to grip the pulling grooves 44 of the body pulling section 41. The clamps 104 are located in a cylindrical collet assembly 106, which is slidably supported in the anvil body 108, which terminates at one end of the crimp anvil section 110 having a crimp cavity 112. The clamps 104 are typically elastically pushed forward along the conical grooves 114 into a radially closed position shown by assembly 116 of the driven clamp mechanism (not shown). However, it will also be understood that, as discussed here, other suitable installation configurations (see, for example, a pin-tail extension portion 177 with a reduced diameter in FIGS. 7-9) and methods other than those shown and described in FIG. 1 -3 are provided by an exemplary fastening system 50 with a low crimp load.

Figures 2 and 3 show an exemplary collar 14 used on two representative types of fastening means 10a, 10b without a pin tail, respectively. The figures further illustrate how an exemplary collar 14 can be easily used in conjunction with a wide variety of known installation tools. For example, FIG. 2 shows an installation tool 200 including an external drive device 202 with an internal threaded channel 204 and a sensing rod 206. This installation tool 200 is also discussed in detail in the '024 patent, which is incorporated herein. Briefly, the external drive device 202 engages with the grooves 26a and actuates or applies relative axial force to the crimping anvil 210 so that it places the clamp 14 in the crimping cavity 212 and engages with the clamp 14 when parts 18a and 20a are held together.

Figure 3 illustrates an exemplary collar 14 used for a non-pin tail fastener of another type 10b. The pin body 15b includes an internal threaded channel 77 adapted for use with an installation tool 300 including an internal drive device 306 with a drive shaft 302 having a thread 304 that corresponds to a thread of the internal channel 77. Such an installation tool is also shown and described in the '024 patent. Briefly, the internal drive device 306 of the installation tool 300 engages with the internal channel 77 of the pin body 15b and pulls the crimping anvil 310 toward the collar 14 so that it fits into and crimping the anvil 310.

Therefore, it will be understood that the strengthened clamp 14 with a low crimp load of the present invention can be used for a wide variety of fasteners and their tools, including fasteners of the type with and without a pin tail, which have traditional ring or screw thread profiles locking grooves with deeper and narrower grooves or a reduced thread pitch compared to the modified thread profile shown in Fig.2-3 and described with the invention of the patent '024, as with shown above. This is a significant improvement, as, as will be briefly discussed below, although the structure of the fastening means of the '024 patent leads to a significant reduction in the required crimp load, in order to do this, it is necessary to radically change the thread profile and heat the clamp (for example, quench and hardening; stress relieving) to achieve the required material properties (e.g. strength). The clamp 14 of the present invention, although applicable to fastening means with the aforementioned modified thread profile (see, for example, FIGS. 2-3), can also be easily used for fastening means having a more traditional thread profile with narrower and deeper locking grooves, see, for example, Fig.7 and 7A and the accompanying disclosure in the patent '024. As will be discussed here, an exemplary reinforced collar 14 can also be easily used with an improved hybrid thread profile 26d (FIG. 6) of an exemplary fastener system 50 of the invention.

According to FIGS. 4 and 5, a prior art collar (eg, 14 ′) is compared with an exemplary collar 14 of the present invention. The collar 14 'includes a bead 59' having an enlarged diameter as desired, with a cylindrical body 61 'and a through channel 65'. The body 61 'of the collar has a generally uniform cylindrical configuration with a uniform, in general, wall thickness t'. The collar 14 'has a straight section 69' of the body, which ends at its outer end with a section 67 'of the body, going the bell radially outward and usually also having a thickness t'.

Like the exemplary collar 14 (Figs. 1-3, 5 and 7) of the present invention, the collar 14 'prior to crimping is adapted to be located above the body 15 of the pin (see, for example, Fig. 1) and when parts 18, 20 are fastened together (FIG. 1) will have a collar body 61 'that is in a radial line with the outer surface 73 of part 20. Parts 18 and 20 have a total thickness t1 (FIG. 1) that defines the nominal grip of the fastening means (for example, 10). However, it will be understood that the fastening means 10 can be used in a predetermined grip interval, varying from parts having a minimum total thickness that is less than t1 (not shown), to a maximum total thickness that is greater than t1 (not shown).

As discussed in the '024 patent, which is incorporated herein by reference, the relative axial load required to crimp the collar body 61' is minimized by reducing the clearance between the straight portion 69 'of the clamp channel having a uniform diameter and the peaks 71 (see, for example , Fig. 1) locking grooves 26. In the invention according to the '024 patent, this radial clearance is significantly reduced in radius, making it a long-standing need to provide an economical, fastening means of high Standard, which shows the optimal combination low crimp load and high strength. Although the aforementioned fasteners essentially correspond to the task of reducing the crimp load, they are still able to solve this problem only with the help of expensive heat treatment of the clamp and changing the thread profile. One of the ways in which the fast crimp fastening system 50 of the present invention overcomes these disadvantages is to provide the aforementioned improved clamp 14, which can be easily used for a wide variety of existing fasteners and their thread profiles and which is hardened without requiring heat treatment, while still exhibiting material properties (e.g., but not limited to strength) of a high Standard (e.g., Standard 5 or Standard 8). The collar 14 is therefore retroactively applicable to existing fasteners as an improved separate component or, alternatively, in combination with other features with a low crimp load of an exemplary fastener system 50.

Figure 5 shows in more detail an isometric view of an exemplary reinforced clamp 14 with a low crimp load, which is shown when used with fasteners 10, 10a, 10b, 10c, 10d in Figures 1-3 and 7, respectively. The portion of the clamp 14 is cut to illustrate an approximate reduced wall thickness t of the clamp 14 (compared, for example, with the thickness t 'of the clamp 14' in FIG. 4). Thus, for fastening means, approximately half the radius of a conventional clamp bolt, see, for example, FIG. 7 of the '024 patent (illustrating the thread profile of a conventional clamp-type fastening means). Due to the narrow radial clearance provided by the minimized inner diameter ID ', the outer diameter OD' can be reduced to a thickness t 'necessary to provide the required volume. Thus, as discussed in the '024 patent, the inner diameter ID' and the outer diameter OD 'are selected to provide the required wall thickness t' of the body 61 'of the clamp, which leads to the required volume of clamp material for crimping and the required amount of filling of the locking groove, while providing the required reduction in crimp load.

However, as shown in FIGS. 4A, 7A, 8A, and 9A of the '024 patent and discussed in the accompanying disclosure, such fastening means and its collar 14' require a modified thread profile to engage locking grooves 26 that are wider and, in general, less deep (compared with the altered groove structure shown in FIGS. 4A, 8A and 9A of the '024 patent for the fastening means of the prior art of FIG. 7A). Additionally, although the modified thread profile of the fastening means helps to overcome the aforementioned high crimp load, it also requires expensive heat treatment of the clamp 14 'to maintain the required material properties (e.g. strength).

Therefore, taking into account the aforementioned known attempts to improve the design of the crimp type fastening means, the collar 14 of the present invention will have an inner diameter ID substantially equal to the outer diameter Db of the tip 71 of the locking groove (FIG. 1), similar to the diameter ID 'of the clamp 14' figure 4. However, the outer diameter OD of the exemplary collar 14 is smaller than the OD 'of the prior art collar 14', resulting in an approximate reduced wall thickness t of the collar body 61. As will be discussed here in more detail, the reduced wall thickness t leads to a smaller volume of material that must be crimped in the locking grooves (for example, 26, 26a, 26b, 26c, 26d in FIGS. 1-3, 6B, 6C and 7, respectively) . In combination with the increased stiffness of the exemplary collar 14, this results in the absence of exceeding the depth of the locking grooves (e.g., 26, 26a, 26b, 26c, 26d), which is directly opposite to many prior art collar designs. Also, with a decrease in clamp ID, the clamp moves a shorter distance during crimping to engage the locking grooves. When crimping the clamps of the present invention, less crimping load is used in the locking grooves, since the clamps have a smaller gap between the outer diameter of the peaks than in the prior art. In the clamping bolt systems of the prior art, a greater clearance was provided between the clamps and the outer diameter of the peaks, so that a large crimp load was applied to the clamp to crimp it in the air before crimping in the locking grooves. The reduced wall thickness t not exceeding the thickness of the locking grooves 26, 26a, 26b, 26c and 26d, and the reduced clearance between the clamp and the outer diameter of the vertices of the clamp bolt reduce the relative axial load required to crimp the approximate clamp 14.

Therefore, the present invention performs a similar task regarding reduced crimp loading in a more economical, improved way compared to the prior art. It will be appreciated that the exact value of the difference or decreasing the thickness t of an exemplary collar wall 14 compared to, for example, with t 'wall collar 14' thickness will ultimately depend in part on the size (e.g., _^1/2 inch, 5/8 inch, ³ / ₄ inches, but not limited to these dimensions) of a specific fastener. For example, in the collar wall thickness difference is likely to be greater between the pair of fastening means compatible standards, whose size is _^3/4 inch, than, for example, between a pair of fastening means compatible standards, the size of which is equal to _^1/4 inch. Examples of the consequences of the reduced thickness t of the body 61 of the collar of the present invention, as well as representative numbers for such thicknesses will be further explained and evaluated in the discussion of the following examples. The examples illustrate and discuss the results of several experiments conducted to evaluate the effects of reduced thickness t of the body 61 of the collar on reinforced, high-strength clamps 14 and fasteners (e.g., 10, 10a, 10b, 10c and 10d). The following examples are provided to further illustrate the improvements and do not limit the invention.

EXAMPLE 1

The aim of the first experiment was to determine whether HS5CF-R12 sized clamps could be used as reinforced clamps to meet the values of Standard 8. The HS5CF-R12 fastener is a commercially available Standard 5 crimp type fastener manufactured by Huck International, Inc. in Waco, Texas.

The experiment included testing the outside diameter (OD), stiffness, crimp load, elasticity and preload of standard, sharply chilled and hardened clamps of Standard 8, which were tested and compared with hardened clamps of Standard 8. The results are presented below in Table 1.

Table 1
Hardened Standard 5 clamp Clamp Description HS5CF-R12 Clamp "A" Clamp "B" Thermal condition Sudden cooling - Hardened 900F processing Quenching voltage Clamp stiffness Rb77 Rb90 Rb89 Outside diameter .568 " .562 " .562 " clamp Elasticity (Special: 13,070 pounds 12,400 12,730 11,600 min) 13% pounds pounds Interest on special. 7% 10% Preliminary 8,390 pounds 8,040 7,570 load (Special: 13% pounds pounds 7,400 min) 9% 2% Interest on special. Crimp load 5,850 pounds 4,860 4,800 Decrease in Standard pounds pounds percent eighteen% eighteen% HS7 Minimum 7,000 pounds on 5,700 5,700 load KB.D. pounds on pounds on Decrease in Standard KB. D. KB.D. percent 19% 19%

As shown in Table 1, both clamps “A” and “B” had a crimp load that was 18% lower than the current standard HS5CF-R12 clamp, and both met the minimum manufacturing requirements for elasticity and preload of Standard 5 The experiment found that the reinforced clamp, Clamp A, had two distinct advantages over Clamp B.

1) The clamp "A" did not require heat treatment (for example, rapid cooling and quenching; stress relieving) and, therefore, did not need an additional stage of cleaning or decarburization of the clamp.

2) Clamp “A” had a significantly larger preload limit compared to the minimum production characteristic than Clamp “B”.

Although the “A” collar did not have the same high actual elasticity and preload as the standard Standard 5 collar, it had a significantly (18%) weaker crimp load. Therefore, testing confirmed that hardened clamps having a reduced OD and thus wall thickness according to the present invention can economically obtain a reduced crimp load (by 18%), while exhibiting optimal material properties.

EXAMPLE 2

The second experiment was the result of the need to develop an economical way to increase the service life of the installation tool and reduce the cost of creating standard 8. clamps. Specifically, the experiment aimed at determining whether thin-walled reinforced clamps can increase the starting load, reduce the crimp load and maintain the same elasticity and preload as standard sharply chilled and hardened clamps. The trigger is the load at which the collar 14 first engages with the locking grooves 26, 26a, 26b, 26c, 26d of the pin. After this point, the elongation of the sheet slit (for example, parts 18, 20; 18a, 20a; 18b, 20b; 18s, 20c) is limited, since the clamp 14 is stuck on the pin 12, 12a, 12b, 12c, 12d. If after the descent there is a gap, the clamping decreases, since the elongation of the clamp begins to decrease the gap instead of stretching the pin 12, 12a, 12b, 12c, 12d.

HSCF-R20 clamps from one work order and source material (elasticity was 50 thousand pounds per square inch) were divided into four groups. HSCF-R20 Clamps are commercially available clamps manufactured by Huck International, Inc. in Waco, Texas.

Group 1 was a control group and was processed in the traditional way (for example, quenching and quenching). The clamp OD was 1.009 ".

Group 2 was hardened and its clamp OD was reduced to 1,000. "

Group 3 was hardened and its clamp OD was reduced to 0.995 ".

Group 4 was hardened and its clamp OD was reduced to 0.990 ".

All clamps were subjected to bead-blasting and waxing to obtain the same surface texture and lubricant. Additionally, for testing, pins from the same work order with the same installation tools and the same test tools were used. For each group, for each category of starting load, crimp load and preload and elasticity, three tests were performed. For simplicity, Table 2 shows only the average test values.

table 2
Thin-walled reinforced clamps Rigidity
Rb Descent
Pounds Swage,
Pounds Preliminary
load,
Pounds (26,080
min) Elasticity,
Pounds
(37,300
min) Sharp
chilled -
Tempered
1.009 "OD 76 5,670 18,730 28,000 38,600 Hardened
1.000 "OD 88 8,770 17,570 28,670 41,570 995 "OD 88 7,590 15,870 27,000 39,470 990 "OD 88 7,300 14,070 24,000 36,970

The range of acceptable values for the OD clamp for standard clamps is from 1.006 "to 1.012". Using the same tolerance range for hardened clamps, the range of available clamp ODs is approximately .995 "to 1.001". As shown, the OD range in Table 2 is approximately from. 990 "to 1.000", and these values can be taken as the minimum and maximum values. The average values of 1.000 "and .995", therefore, can be directly compared with the nominal values of 1.009 ".

As can be seen from the results presented in Table 2, hardened clamps offer the following advantages over standard sharply chilled and hardened clamps:

1. Improved mechanical values: trigger load (slit pull) is approximately 44% greater, crimp load is approximately 11% less, tensile strength is approximately 5% greater, and the same preload. The preload is greater than the minimum industrial characteristic by about 7% for both types of clamps, but the tensile strength improves from about 3%, compared with the minimum characteristic, to about 9%, compared with the characteristic when using a reinforced clamp. The reinforced clamp also provides a reduction in pressure of the installation tool from about 10% to 20%, which is a very significant advantage that leads to reduced tool wear, more affordable, smaller tools and lighter tools.

2. Improved quality: in the absence of sudden cooling and hardening of the clamps, random problems and decarburization problems are eliminated. Additionally, stiffness is maintained since the stiffness range in which the reinforced collars can be located is approximately 10 Rb. It is also possible that certain sharply chilled and hardened clamps may not meet the requirements of elasticity if the stiffness approaches the minimum characteristic of the Standard of 68 Rb. This is not a problem for exemplary reinforced clamps with increased stiffness.

3. Reduced cost: With the exception of heat treatment and the associated sandblasting step, hardened clamps reduce production costs. Additionally, the cost of the clamp’s starting material can be reduced by replacing the AISI 1010 annealed steel wire, which is usually used for the production of clamps, with the AISI 1006 hot-rolled wire, which can be used to produce exemplary reinforced clamps, since the value of its mechanical hardening is essentially , same as AISI 1010 annealed steel wire. Reinforced clamps can be made of unannealed or annealed mild steel. It is also unannealed and therefore less expensive.

4. Reduced development time: The exclusion of heat treatment and associated verification saves two or three days, which are usually necessary for the production of clamps.

Therefore, the results of EXAMPLE 2 further confirm the advantages of using the hardened clamp according to the present invention. Additionally, when considering together with EXAMPLE 1, the ability of the fastening means and its collar of the present invention to reduce the wear of the components of the installation tool (for example, anvils; couplings) and thereby increase the life of the tool becomes apparent. Although anvil wear is expected to increase, since the exemplary hardened clamps are more rigid, the present invention has found that in fact the anvil wear does not change significantly with decreasing OD and thus the wall thickness t of the approximate collar 14, and the clutch service life is increased by decreasing required tool pressure.

EXAMPLE 3

In addition to the results of the first two experiments, the third experiment additionally tested the consequences of increasing clamp stiffness with decreasing clamp wall thickness while trying to find the optimal combination of high strength and low crimp load. Pulling the gap leads to clamping the connection, which is less than optimal. However, increasing the stiffness of the clamp also increases the crimping force to install the clamp, as proved in EXAMPLE 2.

Reducing the wall thickness of the clamp disproportionately reduces the crimping force compared with the trigger load (pulling the gap). Therefore, combining the results of the above experiments, this experiment was aimed at overcoming the limitations of the design of known fasteners by combining increased stiffness of the clamp and reducing the wall thickness of the clamp to maintain the same elasticity and preload and increase the release load while reducing the crimp load, thereby increasing the service life of the installation tool. The objective of the experiment was also to carry out the above standard pin or installation tool without changes so that a possible future replacement with a new clamp was as simple and economical as possible.

For consistency in the experiment, a collar of the same work order was used. The wall thickness of the clamp was reduced by machining the OD of the clamp by .010 ". For optimal wall thickness, the trigger load, crimp load, buoyant load, preload and tensile strength were tested. The most consistent way to significantly increase the clamp stiffness, as EXAMPLES 1 and 2, there was the use of reinforced clamps that give an overall increase in stiffness between approximately 20-25 Rb between points. When the optimum clamp wall thickness was determined, similar to the test The tests were carried out to compare standard pins with the pins described above with the '024 patent, the latter being subjected to heat treatment to obtain the same stiffness and breaking point of the pin, to determine the consequences of the locking groove profile. All tests were carried out on trial operation equipment when using standard verification procedures.

To simplify the report, as well as due to a slight change between the tests, only the average values of three tests for each condition are given. Table 3 shows here the result of an approximate decrease in the wall thickness of the clamp when using pins with a standard thread profile.

Table 3
Reduced clamp wall thickness with standard thread profile Clamp
Rb Clamp
OD ” Clamp
Wall" Descent
Pounds Swage
Pounds Pushing out
Pounds Clamp
Pounds Elasticity
Pounds Sharp
cooled
Tempered 72 .990 .167 6,683 19,366 2,900 26,500 35,300 Hardened 92 .990 .167 11,366 20,766 2,950 29,250 39,666 Hardened 92 .980 .162 10,766 19,033 2,966 28,000 37,633 Hardened 92 .970 .157 9,833 17,277 2,839 26,250 33,366 Hardened 92 .960 .152 8,633 13,433 2,048 18,750 19,586

As can be calculated from Table 3, the calculated OD of the hardened rigid clamp equal to .975 "would give the same clamping and elasticity values as the OD of the currently standard clamp, but the release load would increase by about 54%, and the crimp load would decrease by approximately 6%. These results further confirm the features of the fastening means and its hardened, thin-walled clamps with a low crimp load of the present invention.

The descent, clamping and elasticity data for standard locking grooves (for example, the type discussed with reference to Figs. 7 and 7A in the '024 patent) from this group confirm the first group of data in Table 3. The crimp load was approximately 1,300 pounds lower. than predicted, or was reduced by approximately 12% instead of the initial decrease of 6%. There was no significant difference between the values due to the thread profile of the locking groove. There was a significant (approximately 40%) reduction in crimp load associated with an altered hybrid locking groove and a rigid, thin-walled reinforced clamp compared to crimp loads associated with the standard screw profile of the locking groove thread and a sharply cooled and hardened clamp.

As a result, the experiment confirms that the stiffness can be sequentially increased using hardened clamps, and the wall thickness of the clamp can be reduced, since the ring strength increases due to such high stiffness. Reducing the OD of the clamp to approximately .975 "does not change the actual values of preload or elasticity, but increases the elongation of the slit by approximately 50% and reduces crimping by approximately 10%. Increased stiffness by approximately 20 Rb points also increases the calculated wear resistance of the clamp by approximately 40% and no pin or crimp anvil changes are required to crimp the reinforced clamps, therefore, not only the creation of fasteners and their clamps of the fastening system 50 of the present image This results in optimized physical properties, low crimp loading and economic efficiency, but the clamps 14 can also be easily used with a wide variety of existing fastener pins and thread profiles, as well as with an improved hybrid thread profile 26d (Fig. 6C) according to the invention .

It is desirable that the pin 12, 12a, 12b, 12c, 12d (Figs. 1-3, 6B, 6C and 7) be sufficiently rigid with respect to the stiffness of the clamp 14 to resist crushing or excessive compliance with the stress, or the formation of the neck due to compressive crimp loads. Therefore, in one form of the invention, for example, for fixing means of Standard 5, the pin 12, 12a, 12b, 12c, 12d can be made of AISI 1038 steel or AISI 1541 steel or other comparable materials for the same Standard having a rigidity of from about Rc24 to approximately Rc35 and ultimate tensile strength equal to at least 120 thousand pounds per square. inch. Typically, traditional clamps (e.g. 14 ') for such fasteners are made of AISI 1010 carbon steel, which must be heat treated at a stiffness of approximately Rb65 to approximately Rb85 and a tensile strength of at least about 60 thousand pounds per square meter inch.

However, as discussed above, the example collar 14 is made, for example, of AISI steel or any other suitable material of annealed or unannealed mild steel. AISI 1006 steel is unannealed. Unalloyed steel wire, commonly referred to as “green” wire, is less expensive, which makes it possible to economically produce an exemplary collar 14. Pin 12, 12a, 12b, 12c, 12d has significant rigidity to accept the required high tensile preloads and crimp clamp loads 14 without significant compliance. Additionally, the collar 14, like the collars discussed, for example, in the patent '024, can be coated with a traditional lubricant, such as water-soluble polyethylene wax or cetyl alcohol. Clamp 14 can also be galvanized. This helps to maintain a low level of crimp loads and also minimizes the wear of the crimp cavity 112, 212, 312, 412. Thus, as shown by EXAMPLES 1-3, the body 6 (Figure 5) of the clamp 14 is provided with a sufficient wall thickness t and, therefore, thus, in order to ensure that a sufficient amount of clamp material is moved along the axis extension, but at the same time it will have sufficient strength so that the pin shoulders 60 (FIG. 1) and the clamp shoulders formed during crimping, remained essentially completely grip ennymi when the compound design tensile load. In this sense, the required wall thickness t (FIG. 5) of the exemplary collar body 61 will slightly increase for fasteners having a larger diameter and decrease for fasteners having a smaller diameter, while remaining thin enough to exhibit the advantages found in the present invention , and finer than the known prior art clamps of comparable size and Standard. Table 4 further summarizes the improvements of the clamp 14 by comparing the known sharply chilled and hardened clamps 14 'and the reinforced clamps 14 of the invention used with the known fasteners 10, 10a, 10b, 10c, 10d of Standard 5 and Standard 8 and with improved fasteners 10 s 10d (FIGS. 6 and 7) of Standard 5 and Standard 8 of an exemplary fastening system 50 with a low crimp load. Various sizes of clamp are shown for three different nominal dimensions of the fastening means constituting a _^1/2 inch, 5/8 inch and _^1/4 inch. For the first two types of fastening means, the dimensions of the clamp of the existing sharply chilled and hardened clamp 14 'are shown first, and the values of the reinforced clamp 14 according to the invention are shown directed and shifted to the right. For the fasteners of Standard 5 and Standard 8, entitled “Next Generation”, the values shown are for reinforced clamps only. These fasteners use an exemplary hybrid thread profile 126 (FIG. 6C) of the invention, which will be discussed here.

Table 4
Clamp size; Comparison Modern C50I. Standard 1/2 "Diameter 5/8 "Diameter 3/4 "Open. The size of the gap to the bolt R.Oh. / Zak. .021 .029 .034 clamp I.D. R.Oh. / Zak. clamp .521 .654 .784 O.D. R.Oh. / Zak. clamp .798 .987 1.184 O.D./I.D. R.Oh. / Zak. 1.532 1.509 1.510 clamp Wall R.Oh. / Zak. clamp .139 .167 .200 The size of the gap to the bolt .021 .029 .034 hardened clamp I.D. hardened clamp .521 .654 .784 O.D. hardened clamp .789 .975 1.171 O.D./I.D. hardened 1.514 1.491 1.494 clamp Wall of hardened clamp .134 .161 .193 Modern HP8 / HF / HS Standard 8 The size of the gap to the bolt R.Oh. / Zak. .022 .023 .033 clamp I.D. R.Oh. / Zak. clamp .521 .648 .783 O.D. R.Oh. / Zak. clamp .812 1.009 1.213 O.D./I.D. R.Oh. / Zak. 1.559 1.557 1.549 clamp Wall R.Oh. / Zak. clamp .145 .180 .215 The size of the gap to the bolt .022 .023 .033 hardened clamp I.D. hardened clamp .522 .648 .783 O.D. hardened clamp .803 .998 1,200 O.D./I.D. hardened 1.538 1.540 1.533 clamp Wall of hardened clamp .141 .175 .209 Standard 5 Next Generation The size of the gap to the bolt .010 .013 .016 hardened clamp I.D. hardened clamp .510 .638 .766 O.D. hardened clamp .756 .945 1.134 O.D./I.D. hardened 1.482 1.481 1.480 clamp Wall of hardened clamp .123 .154 .184 Next Generation Standard 8 The size of the gap to the bolt .010 .013 .016 hardened clamp I.D. hardened clamp .510 .638 .766 O.D. hardened clamp .766 .958 1.150 O.D./I.D. hardened 1.502 1.502 1.501 clamp - Wall of hardened clamp .128 .160 .192

As shown in Table 4, for the reinforced collar of the present invention, it was found that the ratio of O.D. to I.D. the hardened clamp is approximately: (i) 1.491 for existing 5/8 inch fasteners of Standard 5, (ii) 1.540 for existing 5/8 inch fasteners of Standard 8, (iii) 1.481 for 5/8 inch standard fasteners 5 of the next generation; and (IV) 1.502 for fasteners in 5/8 inches of Standard 8 of the next generation. Applicable O.D. to I.D. The collar of the present invention would probably range from about 1.47 to 1.55, or any other interval falling within this range. Additional exemplary embodiments of the intervals are not set forth to simplify the description. For sharply chilled and hardened clamps of the prior art, it was found that the ratio of O.D. to I.D. The clamp is approximately: (i) 1.509 for 5/8 inch fasteners of Standard 5 and (ii) 1.557 for 5/8 inch fasteners of Standard 8.

Reducing the crimp load allows you to reduce the size of the installation tool (for example, 100, 200, 300 in Fig.1-3, respectively; see also the installation tool 400 in Fig.7-9), which leads to a corresponding reduction in weight up to 40% compared with the weight of traditional installation tools. See, for example, the '024 patent, as mentioned above, (discussing the weight reduction of the tool compared to tool 148 in FIG. 7 of this patent).

Due to the fact that many fasteners (for example, 10, 10a, 10b, 10c, 10d) with which the collar 14 of the present invention can be used have tightening portions and / or pin tails of a reduced size and / or length, it may be necessary to provide a mechanism for holding the pin and the clamp together during their first preliminary installation on the parts in preparation for installation. Therefore, the clamp can be, if required, provided with a flexible plate 50 (Figure 5) for pre-assembly. See, for example, US Patent No. 4813834. The structure and operation of the optional assembly plate 90, if used, is substantially the same as that disclosed in the '024 patent, as mentioned above, and such disclosure is incorporated herein by reference in its entirety. Briefly, the assembly plate 90 is located in the recessed portion 55 of the channel of the clamp 14 and has a limited circumference. The assembly plate 90, as noted in the '834 patent, as mentioned above, preferably has a flexible structure and can essentially be made of a plastic material, such as, for example, polyurethane. The plate 90 extends radially inward to a distance sufficient to be located inside the locking grooves, such as grooves 26, 26a, 26b, 26c, 26d. Thus, when located in one of the locking grooves, the clamp 14 will be held on the corresponding pin 12, 12a, 12b, 12c, 12d. The plate 90 is located in the recessed portion 55 of the channel, which is in a line with the flange 59. The optional plate 90 facilitates the movement of the clamp 14 on the pin and indexing the plate 90 over the tops of the locking groove. It will be understood that the plate 90 can alternatively be located at the opposite end of the clamp 14. It will also be understood that the use of the optional plate 90 by the clamp is optional.

It will also be understood that one or more portions of the yoke 14 may have a configuration other than that shown and described herein. For example, the collar may not have a side (not shown) or may have a reduced-sized side (not shown), and / or the clamp may not include a recessed portion 55 of the channel. Additionally, the clamp 14 may, if desired, include such a recessed portion of the channel at the opposite end of the clamp (not shown). It will also be understood that, as discussed in US Pat. No. 4,867,625, an optional assembly plate (e.g., 90) may contain a more significant, limited thread (not shown) of a preselected size so that a certain amount of initial clamping of the part is achieved in addition to holding the clamp 14 and the associated pin under pre-assembly conditions on the parts. See, for example, the '625 patent (relating to a limited female thread disclosure, incorporated herein by reference in its entirety).

Another means by which the fastening system 50 with a low crimp load according to the invention reduces crimp loads is shown in FIG. 6C and, in particular, is shown by comparing FIG. 6C with FIGS. 6A and 663. Specifically, as shown in FIG. 6C A hybrid thread profile 26d is provided for the locking grooves 26d of the pin 12d, which improves known thread profiles, such as examples of the thread profile of the wave-shaped locking groove 26b and the deep locking groove 26c in FIGS. 6A and 6B, respectively. The exemplary thread profile in FIG. 6C is determined by a unique hybrid of features, including a number of smoothly conjugated curves that provide a substantially smooth transition between the vertices 28d, 30d and the base of the locking grooves 26d. More specifically, the first vertex 28d has a first rounding R1, the second vertex 30d has a fourth rounding R4, and two intermediate roundings R2, R3 define a base portion or recess 132 of the groove 26d, while smoothly connecting the first rounding R1 and the fourth rounding R4. Thus, the hybrid thread profile 26d (FIG. 6C) improves the relatively smooth and sharp transition between the shallow and deep thread profiles 26b, 26c in FIGS. 6A and 6B, respectively. In particular, the relatively shallow undulating profile 26b in FIG. 6A requires much more rounding and has a relatively intermittent transition between roundings, and the deep thread profile 26c of the locking groove in FIG. 6B has a relatively sharp, smooth transition between roundings. Additionally, the undulating profile 26b in FIG. 6A has a large thread pitch 36b and a relatively shallow depth 38b, while the deep thread profile 26c in FIG. 6B, on the contrary, has a relatively small thread pitch 36c and a much greater depth 38c, as shown.

Continuing to refer to FIGS. 6A and 6B, respectively, it can be appreciated that the wave-like profile 26b tends to exceed the depth when crimping the clamp 14, as discussed previously, which disadvantageously increases the crimping load. On the contrary, as shown, sharp changes in the depth of the thread profile 26c of FIG. 6B tend to have the opposite effect with less than expected grip that occurs between the locking grooves 26c of the pin 12c and the clamp 14 when crimped.

Referring next to FIG. 6C and comparing an exemplary hybrid thread profile 26d with the thread profiles 26b and 26c in FIGS. 6A and 6B, respectively, it will be understood that the hybrid thread profile has to some extent intermediate thread pitch 36d and depth 38d. Together with the aforementioned smoothly conjugated arcs of radii R1, R2, R3, R4, this provides a smooth thread profile 26d with smooth conjugation, which therefore contributes to the corresponding blocking engagement of the grooves 62 of the collar with the locking grooves 26d when crimping the clamp 14, thereby reducing the crimp load. The benefits of an exemplary thread profile 126 can be further appreciated using the values of the following table, Table 5, which summarizes a non-limiting, comparative example of the values for three different 5/8 inch fasteners of Standard 8 having pins 12b, 12c, 12d with different profiles 26b, 26c, 26d of a thread that are shown and described with respect to FIGS. 6A, 6B and 6C.

Table 5
Comparison of thread profiles of fasteners in 5/8 inches of Standard 8 Type of profile Depth
locking
grooves
(inches) Thread pitch
(inches) Crimp
load
(pounds) thread Waved
profile
locking
grooves 0,027 0.130 16,600 Deep
locking
groove 0,032 0,091 14,400 Hybrid
locking
groove 0,028 0,100 14,700

The deep thread profile of the locking groove shown in Table 5 was designed to reduce the problems associated with erasing the internal threaded channel 204 shown in FIG. 2. It was found that increasing the depth of the locking grooves 26c helped to reduce damage to the internal threaded channel 204. Further, it was determined that a tightening mechanism 177 of the type shown in FIG. 7 is not necessary for the deep locking grooves 26c. The hybrid thread profile of the locking groove shown in Table 5 was designed for use with the type 177 tightening mechanism shown in FIG. 7.

As shown, the hybrid locking groove thread profile 26d (FIG. 6C) has a relatively intermediate thread depth 38d and thread pitch 36d compared to the undulating and deep locking groove profiles 26b, 26c of the locking groove respectively, while achieving all of the above advantages, including maintaining a reduced crimp load comparable in general to the deep locking groove 26c in Fig. 6B. It will also be understood that an exemplary hybrid thread profile 26B can be used in conjunction with the aforementioned reinforced clamp 14 to further reduce crimp loads. For example, for 5/8 inch fasteners of Standard 8 in FIG. 6C and Table 5, it can be expected that the crimp load will decrease by about 11% compared to the undulating locking groove profile using the exemplary hybrid thread profile 26d in FIG. 6C together with the aforementioned reinforced collar 14. Also, for fasteners of 5/8 inches of Standard 8 in FIG. 6C and Table 5, it can be expected that the crimp load will decrease by approximately 40% compared to the standard screw profile of the locking groove thread when using Using an exemplary hybrid thread profile 26d in FIG. 6C together with the aforementioned clamp 14.

For the hardened collar of the present invention, it has been found that the ratio of the shear strengths between the pin and the clamp is approximately: (i) 1.8 for the fastening means of Standard 8 and (ii) 1.6 for the fastening means of Standard 5. The applicable interval of the ratios of the tensile strengths between the pin and clamp of the present invention would probably be an interval of about 1.5 to 2.1, or any other interval that falls within this interval. Additional exemplary embodiment of the intervals are not set forth to strengthen the description. For sharply chilled and hardened clamps of the prior art, it was found that the ratio of shear strengths between the pin and clamp is approximately: (i) 2.5 for the fastening means of Standard 8 and (ii) 2.2 for the fastening means of Standard 5.

For the hardened collar of the present invention, it was also found that the locking grooves are usually filled: (i) approximately 40% for the deep groove profile 26c of the locking groove and approximately 60% for the hybrid profile 26d of the thread of the locking groove for the fastening means of Standard 8, and ( ii) approximately 30% for the deep profile 26 of the locking groove thread, and approximately 50% for the hybrid profile of the groove 26d of the locking groove for the standard 5 fastener. It has been found that the use is deeper th locking groove without exceeding the depth of the locking grooves is desirable from the point of view of accommodating the colored coating applied to the pin, which accumulates in the hollows of the locking grooves.

It has also been found that the usual pitch ratio between the pitch of the thread and the depth of the locking groove is approximately 2.8 for the deep thread profile of the locking groove and approximately 3.6 for the hybrid thread profile of the locking groove. The applicable interval of the usual pitch relationship between the thread pitch and the depth of the locking groove would probably be between 2.5 and 4.0, or any other interval that falls within this interval. The pitch ratio between the thread pitch and the depth of the locking grooves for the undulating thread profile of the locking groove of the prior art was approximately 4.8.

7, 8 and 9 show other additional mechanisms for easing crimp loads and, thus, increasing the service life of the installation tool according to the invention. Like the previously discussed hybrid thread profile 26d and hardened clamp 14, the following low crimp mechanisms can also be used independently or in combination with the aforementioned hybrid thread profile 26d (FIG. 6C), or with hardened clamp 14 (FIG. 1- 3, 5, 6A, 6B and 6C), or with both of them.

FIG. 7 shows the fastening means 10d and the mounting tool 400 for fastening two parts 18d, 20d together, the fastening means having a mechanism 177 comprising a substantially straight, relatively short pull-in portion 179 at the second end 19 of the pin 12d. Additionally, four successive steps are shown for installing the fastening means 10d using an exemplary low crimp system 50 according to the method of the invention.

The engaging portion 179 of the pin 12d has a relatively short length 183 and thus extends or protrudes from the second end 19 of the pin 12d a short distance. In fact, the protrusion length 183 of the exemplary entanglement portion is so short that, in contrast to the entanglement portion in the form of a clot of US Pat. not directed to separation during subsequent installation, although separation of the pulling portion 179 is possible by using a dangerous groove on the pin 12d or shaving off the pulling portion 179 with a separating tool in other embodiments of the invention (not shown). This preferably eliminates the impact loading of the setting tool 400, which is known to cause an unexpected rupture of a dangerous groove (see, for example, dangerous groove 40 in FIG. 1). This also eliminates pin tail fragments and noise when the pin breaks. A preferred embodiment of the drawback section in the form of a clot of the '519 patent suffers from these disadvantages. More specifically, for example, for fastening means 10d in 5/8 inches of Standard 8, an exemplary tightening portion 179 extends substantially in line with all tightening grooves 181 having substantially the same diameter D _B that is smaller than the outer diameter D _a the locking portion 25d of the pin 12d as shown. As will be discussed, the direct configuration of an exemplary tightening portion 179 with a reduced diameter D _B contributes to better grip with the setting tool 400 and an increase in tool life. Also, it is much easier to produce than, for example, a narrowed configuration in the form of a clot of the patent '519, where each groove of the tightening section has a different diameter.

Other improvements to the fastening system 50 of the invention are also shown in FIGS. 7, 8, and 9. Specifically, an exemplary installation tool 400 for mounting the fastening means 10d includes a collet 402 having a tightening portion 404 with a plurality of teeth 408 that are designed to greetly engage with the grooves 181 of the tightening a pin portion 179 (e.g., pin 12d), and an anvil member 140 having a crimp cavity 412 for crimping the clamp 14, as previously discussed. The configuration of an exemplary draw-on portion 179 with a reduced diameter D _B , but generally a straight line, allows the thickness T of the cross-section (Figs. 7 and 8) of the collet 402 (Figs. 7 and 8) to be increased. Specifically, the thickness T can be increased up to a value equal to the total difference between the diameters D _a ′ and D _B of the pin locking portion 25 c and the tightening portion 179, respectively. An exemplary tightening radius portion 179 179 also results in less material being required to produce the tightening portion 179 compared to, for example, the tightening and locking portion 25 a of the fastening means 10 a in FIG. 2. This, in turn, allows the tightening grooves 181 of the exemplary tightening section 179 of the pin and the corresponding teeth 408 of the tightening section 404 of the setting tool to have a greater thickness, thereby reducing the abrasion and jamming of the tightening grooves 181. Erasing and seizing of tightening threads are long-standing known disadvantages at this level technicians. The first few turns of thread of a narrowed configuration in the form of a claw of the '519 patent may be sensitive to abrasion and seizing, since these threads have a reduced diameter and, thus, reduced strength and abrasion resistance.

As noted, FIG. 7 also shows a general installation method using an exemplary fastener system 50 with a low crimp load according to the invention. Specifically, as shown, in operation, as soon as the pin 12d is inserted into the through-hole holes 16d, 17d in the parts 18d, 20d, the collar 14 is applied to the second end 19 of the pin 12d. As previously discussed, the collar may be the aforementioned exemplary reinforced collar 14, but not necessarily. The grip portion 179 of the pin 12d then engages with the collet 402 of the setting tool 400. An exemplary collet is the adjustable gripper collet 402, which expands when open (FIG. 7, upper illustration) and contracts when compressed or closed (FIG. 7, second top illustration ), moreover, the teeth 408 of the collet draw section 404 are substantially fully engaged in engagement with the draw grooves 181 of the draw section 179. The setting tool 400 is then actuated, thereby drawing the collet 402 into the crimp w closing anvil 410 and tightening portion 404 of the collet 402, collet 402 is pulled to 12d clamp pin 14 in the cavity 412 crimp anvil 410, thereby applying a radially inward load and the crimp compressing collar 14 into the grooves 26d of the locking pin. The sensing rod 406 then detects that the crimp is completed, determining that the pin 12d is fully tightened, and therefore disables the setting tool 400 by pulling the collet 402, releasing the tightening portion 179 and pulling the collar 14 out of the anvil 410. Therefore, an exemplary installation system 50 and the method significantly improve and simplify the installation of fastening means by achieving all the advantages of the installation in the absence of a pin tail, while avoiding the disadvantages associated with such installation, such as higher nd wear during rotation of the coupling, collet 402 which is replaced with less wear. It also eliminates many other individual components of the installation tool, such as a separate collet, trigger ejector, separate clips and the driven mechanism and spring, and replaces them with essentially one part, an approximate adjustable gripper collet 402. Thus, the invention reduces the installation cycle time , the cost and complexity of the known rotation on the clutch and provides tools that are faster, lighter, quieter and which contains fewer moving parts, which leads to itelnomu cost savings.

It will be understood that other installation methods and configurations other than those shown and described herein may be used. For example, as discussed previously, it is possible to use a pin pulling portion (not shown) or an internal drive pulling mechanism (not shown) configuration without deviating from the scope of the invention. It will also be understood that although it is shown that the tightening portion 179 has annular tightening grooves 181, it is possible to use other thread profiles (for example, screw thread, but not limited to it), if appropriate changes to the installation tool are also made.

The improvements of the exemplary installation tool 400, which are provided by the exemplary configuration of the pin tightening portion, will be further evaluated with reference to FIGS. 8 and 9.

FIG. 8 shows a portion of the draw section 404 of an exemplary adjustable gripper collet 402 for the setting tool 400. The draw section 404 has an engaging end 405 (left oriented in FIG. 8) and a plurality of teeth 408. In the example of FIG. 8, the pull section 404 has four teeth 408. The first tooth 409, which is adjacent to the engaging end 405, has a first inner diameter ID ₁ . The remaining teeth 408 have a second inner diameter ID ₂ , which is less than ID ₁ . By revealing the inner diameter ID _{1 of the} first tightening tooth 409, as shown, the construction of the collet according to the invention prevents this tooth 409 from spalling.

Specifically, the apex (shown by the dashed line in FIG. 8) of the exemplary first prong 409 is removed to reveal the inner diameter of ID ₁ at this position. This, in turn, moves the primary load point from this position to a position that is additionally pushed back to the tightening section 404 (for example, to the right with respect to FIG. 8), thereby reducing the instantaneous load by the farthest front radius r of the tooth base 409 and thus increasing the fatigue life of the collet 402. More specifically, for example, referring to the height h of the first tooth in the example of FIG. 8, a reduction in tooth height by approximately 30% leads to a significant increase in the tool fatigue life nta 400 for approximately 24,000 setting cycles with a crimp pressure of approximately 12,000 pounds for Standard 5 fasteners having an approximate tightening portion 179 (FIG. 7) since the front tooth 409 had previously been damaged after 14,000 cycles. This significant improvement is the result, as discussed earlier, of a decrease in the bias lever applied to the front tooth 409 due to an increase in ID ₁ , which shifted the damage state back to a stronger area (for example, the fourth tooth 408 on the left) of the pulling portion 404 of the collet 402. This is an additional improvement to the aforementioned increase in tool life, which gives an increased thickness T of the wall of the collet 402. Additionally, as discussed previously, all this is achieved by using an approximate nokomponentnoy adjustable gripping collet 402 that is adapted to expand and contract without requiring separate clamps or separate trigger pusher driven gear and a spring. This is due to the fact that the exemplary adjustable gripper collet 402 includes one or more slots (not shown) that allows the collet to be compressed from a relaxed or open position (upper illustration in FIG. 7) to a closed or compressed position (second illustration in FIG. 7) when it is pulled into the inner channel 420 (FIG. 7) of the anvil 410, which exerts a radially directed force to close the pulling section 404 of the collet. However, it will be understood that for engaging and tightening the pin tightening portion 179 (FIG. 7), for example, any known or suitable alternative collet design (not shown) having, for example, separate lockable clips (not shown), can be used, not limited to them.

Fig. 9 shows yet another advantage of an exemplary fastener system 50 with a low crimp load.

Specifically, an exemplary crimp anvil 410 includes a crimp cavity 412, which, as shown, has a radius-curved inlet portion 414 to facilitate initial engagement with the collar 14 (FIG. 7), a crimp pad 416, and an inner channel 420. The crimp pad 416 has the first diameter D ₁ , and the inner channel 420 has a second diameter D ₂ that is larger than the first diameter D ₁ . Therefore, the diameter D _{2 of the} inner channel, which opens behind the crimp pad 416, weakens the compressive crimp load on the clamp 14 (Fig.7). This is possible due to the relatively narrow (i.e. small) approximate crimp pad 416 (best seen when viewing a close-up view of the cross section in FIG. 9). The narrow width 418 of the crimp pad defines a small crimp region, since then it leads to the inner channel 420 having a larger diameter D2, unlike the case with one continuous diameter for the full, essentially, length L of the crimp anvil 410. The increased diameter D _{2 of the} inner channel 420 of an exemplary anvil 410 also provides space for containing a thicker and thus stronger wall thickness T of the collet 402 (FIGS. 7 and 8), thereby further increasing tool life. In addition, the length L of the improved anvil 410 according to the invention can also be shortened in comparison with, for example, the anvil 110 in FIG. Therefore, the low crimp fastening fastening system 50 of the invention also provides a number of improvements to the installation tool 400 by reducing the number of tool parts, reducing the weight of the tool, reducing the crimping loads required by the tool, reducing the tool creation cost, and increasing the expected tool life.

Details of the interaction of the clamp and bolt are shown with reference to Fig.6A, 6B and 6C. When they try to tighten the clamp for the first time with a preload bolt, the clamp is not strong enough, so the first vertex of the bolt moves the clamp, creating an empty space and rolling the clamp material opposite the top of the bolt. The same thing happens to a lesser extent on the second top of the bolt. As a result, a sufficient amount of material of the clamp engages with the bolt, so that the formation of empty space and rolling of the material does not occur. This happens faster when using hardened clamps that are harder than sharply chilled / hardened clamps, as they have a higher shear strength. Harder clamps are bolted together faster and create more preload.

FIG. 10 is a sectional view of an improved fastening portion of a fastener pin and a configuration of a setting tool according to an embodiment of the invention and four successive installation steps for crimping a clamp of a fastening means with an improved tightening portion of a pin using various collets. A system similar to that of FIG. 7 is shown. Figure 11, which is similar to Figure 8, shows a cross-sectional view of the end section of various collets for the installation tool in Figure 10.

In the disclosure in FIGS. 10 and 11, there is a fastening system with a low crimp load for crimp type fastening means, the structure of which is designed to hold together many parts. The crimping type fastening means includes a pin member having an elongated pin body adapted to be located in the holes of the parts in the same line. The pin element at one end ends on an enlarged head adapted to adhere to the surface on one side of the parts, and on its opposite side ends on a furrowed portion that can extend beyond the opposite surface on the opposite side of the parts. The furrowed portion comprises a locking portion having a plurality of locking grooves that define a pin grooves extending around the circumference and associated pin shoulders ending at the tips of the pin.

The installation tool includes an anvil member 40 with a crimp cavity. There is a reinforced clamp 14 including, in general, a straight clamp body adapted to crimp in said locking grooves on a pin member in response to a relative axial force or crimp load applied between the pin member and the reinforced clamp of a mounting tool.

The desired trigger load on parts that are held together forms a bond. The structure of the crimp cavity of said installation tool is adapted to engage with said collar body and to crimp it radially inward. When crimping, the reinforced collar has grooves and shoulders of the clamp that engage with said grooves and shoulders of the pin. The pin member and said reinforced collar are made of various materials having different ultimate shear stresses in order to avoid essentially yielding of said pin element when crimping said clamp on said pin element.

Collet 600 has a protrusion 602 of said collet, by means of which the length of the pulling portion 604 increases towards the clamp 14, which increases the contact area with the anvil 410. An increase in the length of the pulling device increases the contact area with the anvil, which reduces pressure and seizing. It also provides for the return of the angle of the thread, as a tightening device, through a smaller channel anvil.

The reinforced clamp does not require heat treatment, and, in general, the straight body of the reinforced clamp clamp has a wall thickness that is relatively thinner, which reduces the crimp load required by the reinforced clamp.

The protrusion 600 forms a flat circular front surface 600 in front of and adjacent to the lead thread 608 of the collet 600. There is a circular front face 610 sloping forward in front of the flat face 606. There is a second flat face 612 and a corner flat face 614 behind the intersection line 616 with the outer diameter of the collet 600. The tensile strength of the last bolt tip is increased due to the absence of rolling down diameter threadless head at the end of the bolt

The end 618 of the rod 620 does not roll to the diameter position, which is in line with the base 622 of the groove 624. This increases the tensile strength when shifting the tip 626 of the end of the rod 620. The teeth of the tightening device cut the threads of the bolt on line 636.

The last peak 626 thrust has a contour 628 corresponding to the increased radius 630 of the tightening device of the last tooth 620 of the collet 600.

Also, the shortened first tooth 632 of the tightening device, increasing its thickness 634, thus reduces chipping.

In view of the foregoing, the invention provides a fastening system with a low crimp load and a method with many improved features of the fastening means and installation tool, including a reinforced clamp, a hybrid locking groove thread profile, an improved pin tightening portion, and many installation tool improvements that are all individually or in any suitable combinations reduce crimp loads and improve the installation of crimp type fasteners.

Although specific embodiments of the invention have been described in detail, those skilled in the art will appreciate that various changes and alternatives to these details may be devised in light of the general spirit of the disclosure. Therefore, the specific embodiments disclosed are intended to be illustrative only and do not limit the scope of the invention, which is fully set forth in the appended claims and any, and all its equivalents.

Claims (26)

1. A fastening system with a low crimp load for crimping type fastening means made to fasten together a plurality of parts, said crimping type fastening means including a pin member having an elongated pin body adapted to be placed in openings of the same line in details, wherein said pin element at one end ends on a head adapted to adhere to the surface on one side of the parts, and on its opposite end ok starts on a furrowed portion configured to protrude beyond the opposite surface on the opposite side of the parts, said furrowed portion comprising a locking portion having a plurality of locking grooves which are formed by circumferential grooves of the pin and associated shoulder shoulders of the pin ending at the tips of the pin, wherein said fixing system with a low crimp load comprises:
an installation tool including an anvil element with a crimp cavity; and
a hardened clamp, including, in general, the straight body of the clamp, capable of being crimped in said locking grooves on said pin member in response to a relative axial force or crimp load applied between said pin member and said hardened clamp mentioned installation tool, thereby providing the required trigger load on the parts fastened together, with the formation of a fastened connection, and the said anvil element with crimp strips The aforementioned installation tool is adapted to adhere to the body of the collar and crimp it radially inward, wherein said reinforced collar when crimped forms grooves of the collar and shoulders of the collar that engage with said grooves of the pin and shoulders of the pin, wherein said pin element and said reinforced collar have different values of the ultimate tangential stresses, in order to essentially avoid the compliance of the mentioned element of the pin when crimping said clamp on the mentioned nut element of the pin;
wherein said hardened clamp does not require heat treatment, and, in general, the straight body of the clamp of said hardened clamp has a reduced wall thickness configured to reduce the crimp load necessary to crimp said hardened clamp. 2. The fastening system according to claim 1, wherein the relatively thinner wall thickness of the substantially straight body of the collar of said reinforced collar is configured to resist exceeding the depth of said locking grooves of said pin element, thereby further reducing the crimp load necessary to crimp said reinforced collar . 3. The fastening system according to claim 1, wherein said collar exhibits physical properties sufficient to comply with a Standard of fastening means selected from the group consisting of Standard 5 and Standard 8. 4. The fastening system according to claim 3, in which the hardness of said hardened clamp is approximately 85 to 96 on the Rockwell scale (HRB). 5. The fastening system according to claim 1, in which the aforementioned reinforced clamp is made of unannealed or annealed mild steel. 6. The fastening system according to claim 1, wherein said collar includes an enlarged flange at one end of said collar body, said enlarged flange being able to engage with an opposite surface of an adjacent one of said parts. 7. The fastening system according to claim 1, comprising an assembly plate adapted to engage with said locking grooves on said pin element to hold said fastening means in an assembly position at a possible predetermined preload before crimping said hardened clamp. 8. The fastening system according to claim 1, wherein said hardened clamp has an outer diameter and an inner diameter; and in which the ratio of the outer diameter to the inner diameter of the clamp is from about 1.47 to 1.55. 9. A fastening system with a low crimp load for securing together a plurality of parts using crimp type fastening means, said fastening system with a low crimp load comprising:
a pin member having an elongated pin body configured to be placed in holes on the same line in the parts and ending at the first end on the head, which is engaged with the surface on one side of the parts, and ending at the second end on the furrowed portion that extends beyond the boundaries of the opposite surface on the opposite side of the parts, wherein said groove portion comprises a locking portion having a plurality of locking grooves that are formed by passing about the circle with the grooves of the pin and the shoulders of the pin connected with it ending at the tops of the pin, said locking portion of said pin element having an outer diameter;
a substantially straight pulling portion that extends from the second end of said pin member and includes a plurality of pulling grooves, said pulling portion having an outer diameter that is smaller than an outer diameter of said locking portion of said pin element;
an installation tool including an anvil element with a crimp cavity, and a collet having an addictive portion with a plurality of teeth configured to engage appropriately with the addictive grooves of the addictive portion; and
a collar comprising a substantially straight clamp body configured to crimp said locking grooves on said pin member in response to a relative axial pulling force applied to said pulling portion of said pin member by said pulling portion of said mounting tool, thereby providing the required trigger load on the parts to be bonded together to form a bonded joint, the anvil element having a crimp The thickness of said installation tool is adapted to apply a crimp load by engaging with the body of the collar and crimping it radially inward, said crimping collar forming grooves of the collar and shoulders of the collar engaging with said grooves of the pin and shoulders of the pin, said pin element and said the clamp has different values of the ultimate tangential stresses, in order to essentially avoid the compliance of the mentioned element of the pin when crimping the said clamp on said pin member. 10. The fastening system according to claim 9, in which all tightening grooves of said tightening portion of said pin element have substantially the same diameter; however, all the teeth of said addictive section of said installation tool are fully engaged with addictive grooves of said addictive section to resist abrasion and seizure of said addictive grooves. 11. The fastening system of claim 10, wherein said tightening portion of said installation tool has an engaging end;
wherein the first tooth of said teeth of said entanglement portion, which is adjacent to said engagement end, has a first inner diameter, wherein the remaining teeth of said entrainment portion have a second inner diameter; wherein the first inner diameter of said first tooth is larger than the second diameter of said remaining teeth. 12. The fastening system according to claim 9, in which the collet of said installation tool has a section thickness; wherein the difference between the outer diameter of the locking portion of the pin member and the smaller outer diameter of the tightening portion of said pin member provides a corresponding increase in said section thickness of said collet, thereby increasing the fatigue life of said mounting tool. 13. The mounting system according to claim 9, in which said collet is made in the form of a single adjustable gripping collet; moreover, the addictive section of the said movable gripping collet is made expandable for receiving said addictive section of the said pin and compression element for the corresponding engagement of the said teeth of the said addictive section with the said draw grooves of the said addictive section, without requiring the rotation of the collet in the draw section and use of a separate ejector, a separate pair of opposite clamps and a separate driven mechanism and springs. 14. The fastening system according to claim 9, in which the crimp cavity of said anvil element of said installation tool has a radially inlet portion adapted to receive said collar, a crimp pad adjacent to said inlet portion and having a first diameter and an inner channel, having a second diameter, wherein said crimp pad is configured to provide said crimp load directed radially inward to said collar; wherein said crimp pad is relatively narrow in order to reduce the crimp load required to crimp said clamp; moreover, the second inner diameter of said inner channel is larger than the first inner diameter of said crimp pad to weaken some of the said radially inward crimp load and thereby reduce said load. 15. A fastening system with a low crimp load for securing together a plurality of parts when using fastening means of a crimp type, said fastening system with a low crimp load comprises:
a pin member having an elongated pin body configured to fit in the holes on the same line in the parts and ending at the first end on the head, which engages with the surface on one side of the parts, and ending at the second end on the furrowed portion that extends beyond the opposite surface on the opposite side of the parts, said groove portion comprising a locking portion having a plurality of locking grooves that are formed by passing along a circumferential spines with the grooves of the pin and the shoulders of the pin connected with it ending at the tops of the pin, said locking portion of said pin element having an outer diameter;
an installation tool including an anvil element with a crimp cavity, and
a clamp comprising generally a straight clamp body adapted to crimp in said locking grooves on said pin element in response to a relative axial force or crimp load applied between said pin element and said collar with said setting tool, thereby providing the required the value of the trigger load on the parts to be bonded together with the formation of a bonded joint, wherein said anvil element with a crimp cavity of said installation tool The entrances are adapted to adhere to the body of the collar and crimp it radially inward, while the collar during crimping forms grooves of the collar and shoulders of the collar that engage with said grooves of the pin and shoulders of the pin, said pin element and said collar having different values of limit tangent stresses, in order to substantially avoid the compliance of said pin element when crimping said collar on said pin element;
wherein said locking grooves of said pin element are formed with a thread profile formed by a certain number of roundings for each of said pin grooves, said pin shoulders and said pin vertices of said locking grooves, said rounding being smoothly conjugated to obtain a substantially smooth transition between said roundings and thereby contributing to an appropriate locking engagement of said collar grooves with said locking grooves kami when broken down in the said clamp and to reduce the crimp load required for swage of said collar. 16. The fastening system of claim 15, wherein said vertices of each pin groove include a first vertex and a second vertex; wherein the distance between said first and second vertices determines a thread pitch of said locking grooves; wherein said roundings include first, second, third and fourth roundings; wherein said second rounding and said third rounding define a lower portion of said pin groove, said first, second, third and fourth rounding being smoothly coupled to provide said substantially smooth transition between them. 17. The fastening system according to clause 16, in which the thread profile formed by the aforementioned smoothly conjugated curves is selected from the group consisting of an annular thread profile, and a screw thread profile, and a wavy thread profile. 18. The fastening system of Claim 15, wherein the ratio of the shear strengths between said pin member and said collar is from about 1.5 to about 2.1. 19. The fastening system of claim 15, wherein each said locking groove has a thread pitch and depth; wherein the ratio of thread pitch to depth is approximately 2.5 to 4. 20. A method of installing crimp-type fastening means using a fastening system with a light crimp load, said fastening means including a pin member having an elongated body, said pin member at the first end ending at the head and ending at the furrowed portion at the second end wherein said grooved portion comprises a locking portion having a plurality of locking grooves which are formed by circumferential grooves of the pin and the shoulders connected to it Ifa, ending on the tops of the pin, while the aforementioned method contains the stages in which:
inserting said elongated body of said pin element into openings in a plurality of parts;
applying a clamp to said pin member, said clamp having a substantially straight clamp body configured to crimp said locking grooves on said pin member so that the crimped said clamp forms grooves of the clamp and shoulder of the clamp that engage with said grooves of the pin and pin shoulders;
engaging an engaging portion of said pin member with a setting tool, said engaging portion being made straight at the second end of the stud member, said engaging portion including a plurality of engaging grooves and having an outer diameter that is smaller than an outer diameter of said locking portion of said pin member, moreover, the said installation tool contains an anvil element with a crimp cavity and a collet having an addictive section with many teeth, made with the possibility of appropriate engagement with the tightening grooves of said tightening section;
driving said installation tool, thereby closing said draw section of said collet to properly engage said teeth with draw grooves of said draw section and draw said collet into said anvil element, said collet pulling said pin element and said collar into said anvil element crimping said collar in said locking grooves; and
the installation tool is taken out of operation to pull out the collet, releasing said tightening portion and ejecting said collar when said fixing means are installed and said parts are clamped together. 21. The method according to claim 20, in which, as said collar, a reinforced collar is used that does not require heat treatment. 22. The method according to claim 20, in which additionally used as said locking groove of said pin element is a locking groove which is formed by a certain number of roundings for each said locking groove, said rounding smoothly conjugating to obtain a substantially smooth transition between said rounding and thereby contributing to an appropriate locking engagement of said collar grooves with said locking grooves when crimping said collar. 23. A fastening system with a low crimp load for crimping type fastening means configured to fasten together a plurality of parts, said crimping type fastening means including a pin member having an elongated pin body configured to fit in holes on the same line in the details, the aforementioned pin element at one end terminating on a head configured to adhere to the surface on one side of the parts, and on its opposite side nce ends on a grooved portion configured to protrude beyond the opposite surface on the opposite side of the parts, said grooved portion comprising a locking portion having a plurality of locking grooves that are formed by circumferential grooves of the pin and associated shoulder shoulders of the pin ending at the tips of the pin and wherein said fastening system with a low crimp load comprises:
a tightening section made straight on the opposite side of the pin element and including a plurality of tightening grooves;
an installation tool including an anvil element with a crimp cavity; and
a hardened collar comprising a substantially straight body of the collar configured to crimp it into said locking grooves on said pin member in response to a relative axial force or crimp load applied between said pin member and said hardened clamp mentioned installation tool, thereby providing the required amount of release load on the parts fastened together to form a fastened connection, wherein said anvil element is crimped the cavity of said installation tool is adapted to adhere to said collar body and crimp it radially inward, said crimped reinforcing collar forming collar grooves and collar shoulders engaging with said pin grooves and pin shoulders, said pin element and said reinforced clamp the magnitude of the ultimate tangential stresses, in order to essentially avoid the compliance of the mentioned element of the pin when crimping said clamp on said th element of the pin, while the end of the tightening section of the element of the pin is not crimped to the diameter of the base of the tightening grooves, which increases the tensile strength when shifting the tip of the end of the tightening section;
wherein said hardened clamp does not require heat treatment, and, essentially, the straight body of the clamp of said hardened clamp has a reduced wall thickness configured to reduce the crimp load necessary for said hardened clamp. 24. A fastening system with a low crimp load for crimping type fastening means configured to fasten a plurality of parts together, said crimping type fastening means including a pin member having an elongated pin body configured to fit holes on the same line in the details, the aforementioned pin element at one end terminating on a head configured to adhere to the surface on one side of the parts, and on its opposite side nce ends on a grooved portion configured to protrude beyond the opposite surface on the opposite side of the parts, said grooved portion comprising a locking portion having a plurality of locking grooves that are formed by circumferential grooves of the pin and associated shoulder shoulders of the pin ending at the tips of the pin and wherein said fastening system with a low crimp load comprises:
a tightening section made straight on the opposite side of the pin element and including a plurality of tightening grooves;
an installation tool including an anvil element with a crimp cavity, and a collet having an addictive section with a plurality of teeth, adapted to engage with the addictive grooves of said addictive section; and
a hardened clamp, including, in general, the straight body of the clamp, configured to crimp them in said locking grooves on said pin element in response to a relative axial force or crimp load applied between said pin element and said hardened clamp mentioned installation tool, thereby providing the required trigger load on the parts fastened together with the formation of the fastened connection, and the said anvil element with a crimp The aforementioned installation tool is adapted to adhere to the body of the collar and crimp it radially inward, wherein said reinforced collar when crimped forms the grooves of the collar and the shoulders of the collar that engage with the said grooves of the pin and the shoulders of the pin, wherein the said pin element and the mentioned reinforced collar have various values of ultimate tangential stresses, in order to essentially avoid the compliance of said pin element when crimping said clamp on said the right pin element, and the last vertex of the tightening portion of the pin element includes a contour that corresponds to the increased radius of the last tooth of the collet of the tightening device;
wherein said hardened clamp does not require heat treatment, and, essentially, the straight body of the clamp of said hardened clamp has a reduced wall thickness, made with the possibility of reducing the crimp load required for said hardened clamp. 25. A method of installing crimp type fastening means using a fastening system with a light crimp load, said fastening means including a pin element having an elongated pin body, said pin element at the first end ending at the head and ending at the furrow at the second end a portion, said grooved portion comprising a locking portion having a plurality of locking grooves which are formed by circumferential grooves of the pin and associated shoulders pin cams ending at the tops of the pin, said method comprising the steps of:
inserting said elongated body of said pin member into openings in a plurality of parts;
applying a collar to said pin member, said collar having a substantially straight collar body configured to crimp in said locking grooves on said pin element such that when crimped, said collar forms collar grooves and collar shoulders that engage with said pin grooves and pin shoulders;
engaging the engaging portion of said pin member with a setting tool, said engaging portion being made straight at the second end of the stud member, wherein said engaging portion includes a plurality of engaging grooves and has an outer diameter that is smaller than the outer diameter of said locking portion of said stud member moreover, said installation tool comprises an anvil element with a crimp cavity and a collet having an addictive section with many teeth Adapted to engage the respective infeed grooves of said tightening portion, the end portion is tightened to a value not crimped diameter of the base of the pin member spanning the grooves, thereby increasing the shear strength of the fastening end of the top portion of the pin member;
driving said installation tool, thereby closing said draw section of said collet to properly engage said teeth with draw grooves of said draw section and draw said collet into said anvil element, said collet pulling said pin element and said collar into said anvil element crimping said collar in said locking grooves; and
the installation tool is taken out of operation to pull out the collet, releasing said tightening portion and ejecting said collar when said fixing means are installed and said parts are clamped together. 26. A method of installing crimp type fastening means using a fastening system with a light crimp load, said fastening means including a pin element having an elongated body, said pin element at the first end ending at the head and ending at the furrowed portion at the second end wherein said grooved portion comprises a locking portion having a plurality of locking grooves which are formed by circumferential grooves of the pin and the shoulders connected to it ifa, ending on the tops of the pin, and the aforementioned method contains stages in which:
inserting said elongated body of said pin member into openings in a plurality of parts;
a clamp is applied to said pin element, said clamp having a generally straight clamp body adapted to be crimped in said locking grooves on said pin element such that when crimped, said clamp forms grooves of the clamp and shoulder of the clamp mating with said grooves pin and pin shoulders;
engaging an engaging portion of said pin member with a setting tool, said engaging portion being made straight at the second end of the stud member, said engaging portion including a plurality of engaging grooves and having an outer diameter that is smaller than an outer diameter of said locking portion of said pin member, wherein said installation tool comprises an anvil element with a crimp cavity and a collet having an addictive section with many teeth Adapted to engage the respective infeed grooves of said tightening portion, and the last vertex of the fastening portion of the pin member includes a contour which corresponds to the increase in the radius of the last tooth of the collet;
driving said installation tool, thereby closing said draw section of said collet to properly engage said teeth with draw grooves of said draw section and draw said collet into said anvil element, said collet pulling said pin element and said collar into said anvil element crimping said collar in said locking grooves; and
the installation tool is taken out of operation to pull out the collet, releasing said tightening portion and ejecting said collar when said fixing means are installed and said parts are clamped together.

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