MXPA99002318A - Brazier whose thread is not seated - Google Patents

Abstract

The present invention relates to a fastener with anti-tapping cords comprising: a spigot portion having an axial dimension and a distal end, first cords formed on a portion of the spigot portion, where the first cords have a larger diameter , a smaller diameter and a flank first angle, second cords formed on a portion of the shank portion proximal to the distal end, where the second cords have two generally flat flanks converging to form a crest of conventional machine cords generally pointed , and the second cords have a larger diameter smaller than the greater diameter of the first cords, a smaller diameter equal to the smaller diameter of the first cords, and a second flange angle greater than the flank angle of the first cords, where an angle is defined of bevel by means of a crest of a first cord and a crest of a second adjacent cord, and the bevel angle e s about 14 grad

Description

BRAZIER WHOSE THREAD DOES NOT STOP BACKGROUND OF THE INVENTION The invention relates, generally, with threaded fasteners, and in particular, relates to improved fasteners whose thread does not break. Threaded fasteners of the type that include a portion of the body, which is threaded in the form of a helix, are the best known and widely used. These include various threaded body members around which a nut, or other member, is installed having a complementary tapped hole. Frequently, the members of the threaded body are formed as bolts with a tool for hooking them, or a key end, to which a torque is applied for installation, but more generally, can include any threaded body protruding from an article or machine . It is also known that threaded fasteners tend to be damaged during placement. Generally, cross threading occurred due to angular or axial misalignment between the threaded members, during their placement, and is particularly problematic for inexperienced workers and in automatic laying operations, which results in a reduction in productivity and damage of the components, which generally can not be reused. The problems associated with cross threading or in which the thread is damaged have already been recognized, and efforts have been made to eliminate, or at least reduce the occurrence of, them. For example, U.S. Patent No. 3,828,604, issued August 14, 1974, entitled "Method and Apparatus for Forming Screw Tips" (Method and apparatus for for ing types of screws) of the same successor hereby, discloses a method for making threaded fasteners having a portion of the curved tip, which facilitates the placement thereof in a complementary threaded core. The International Publication of WIPO, with the number WO 97/04241, entitled "Bra whose thread does not break" (Anti-Cross Threading Fastener), published on February 6, 1997, discloses a fastener with two or more diameters , relatively narrow and transition ropes or threads, curves, which can reduce the crossing of the thread when angular and axial misalignment are not excessive. However, in the publication No WO 97/04241, the portion of the threaded body near the tip limits the angular misalignment which is compensated by the threaded curves. In other embodiments presented in Publication No. WO 97/04241, the non-threaded tip of the fastener, or the point of gripping or fastening, has a reduced diameter similar to the limits of angular misalignment that is compensated by the curved threads . In general, the present invention is directed to advances in the technique of threaded fasteners, and in particular it relates to novel improvements in fasteners whose thread is not crossed or damaged, including bolts, screws and other threaded body members. An object of the present invention is to provide fasteners with a thread that does not break or crossover, to solve the problems of the prior art, and whose production is economical. Another object of the invention is to provide novel fasteners whose thread does not break or cross, which are easy to install, and which are installed relatively easily and appropriately, and which can be installed under conditions of angular and axial misalignment, a situation which is not it was compensated with the threaded fasteners of the prior art. In addition, another objective of the invention is to provide fasteners with a thread that does not break or cross, which can be used in applications where the thread is susceptible to being damaged or crossed, including the operations carried out by inexperienced workers and, especially, by automatic fasteners.

A more particular objective of the present invention is to provide fasteners whose thread does not break that have a threaded body portion with a larger diameter and smaller diameter, and a portion of the guide body that has no threads and that has a diameter smaller than the largest diameter of the threaded portion of the body. The guide body portion includes a portion of the tip that has at least one substantially curved surface, and a slot disposed about the body between the tip portion and the threaded body portion. A related object of the present invention is to provide fasteners whose thread does not break or cross over from the type to be discussed, more particularly by the way, which also have a cylindrical portion of the body between the tip portion and the groove thereof. A more particular object of the invention is to provide fasteners whose thread does not spoil or deform having a threaded body portion and a sharp, narrower portion toward the tip portion of the body. The cords or threads of the screws of the threaded body portion, sharp, have a flank angle greater than the flank angle of the cords of the screw that is not sharpened, or in the rest of the portion of the threaded body. Another, even more particular object of the invention is to provide fasteners whose thread does not break which have a portion of the threaded body, and a portion thereof tapers towards the tip portion of the body. At least some of the cords or threads of the screw in the threaded body portion, narrow, form separate projections. Still another object of the invention is to provide fasteners whose thread does not spoil or deform, which have various combinations of configurations which will be discussed below. These and other objects, aspects, features and advantages of the present invention will become more comprehensible after careful consideration of the detailed description of the invention and its drawings, which, on occasion, appear disproportionate to facilitate understanding, and where similar structures and steps have numerical references and corresponding indicators. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial, side view of a threaded fastener according to the exemplary embodiment of the invention. Figure 2 is a partial side view of a threaded fastener according to an exemplary embodiment of the invention.

Figure 3 is a view of a partial section of a threaded fastener according to the misalignment presented by the invention during placement in a complementary threaded hole. Figure 4 is another partial view, in section, of a threaded fastener in accordance with the misalignment of the present invention, during placement in complementary threaded hole. DETAILED DESCRIPTION OF THE INVENTION Figures 1 to 4 illustrate a fastener whose thread does not break or deform according to the present invention, in which the threaded portion of the bolt body has an end for the key, which is not shown, or in general, any member with the threaded body projecting from the article or the machine and engaging in the nut bore or in any other threaded member. The fastener whose thread does not break or deform 10 generally includes a body 20 having an axial dimension 22 and a guide portion 24 with a tip portion 26. The threads of the screw 30 are formed in a portion of the body portion 20, in which the threaded portion of the body 30 has a larger diameter and a smaller diameter. The smaller diameter of the threaded body portion 32 may have a diameter equal to or smaller than that of the body portion 34. In one embodiment, the guide portion 24 of the body part 20 is threadless and smaller in diameter. that the larger diameter of the threaded body portion 30. And in another embodiment, the guide portion 24 of the body portion that lacks threads in the screw has a smaller diameter than the smaller diameter of the threaded portion of the member 60. In one embodiment, the tip portion 26 of the body portion 20 has at least one substantially curved surface 28, which may include a relatively flat end portion 27, as shown in the exemplary embodiment . The substantially curved surface 28 may be substantially spherical or elliptical or parabola shaped, or any other curved surface, having or not having a relatively flat end portion 27. The substantially curved surface 28 facilitates the placement of the end portion 24, of the part of the body 20, in the nut or in another member with additional thread, when there is an axial and angular misalignment between them, and also facilitates the alignment of the body portion 20 with the nut or any member with additional thread, during the installation thereof, in the manner as discussed above. A substantially annular groove 40 is arranged around the body portion 20 between the at least partially curved surface 28 of the tip portion 26 and the threaded part of the body 30. Figure 3 illustrates a fastener whose thread does not break or deforms 10, which is placed on the nut or on any other member with additional thread 69 which has a relatively wide misalignment of about 35 degrees between them. The substantially annular groove 40 accommodates a portion of the annular rim 62 of the nut 60, thereby facilitating the initial positioning and retention of the guide portion 24 of the fastener in the hole 64 of the nut 60 at a greater angular misalignment than possible in the absence of the orifice 40. Figures 3 and 4 illustrate a partially curved surface 28 of the tip portion 26, which allows and facilitates an angular orientation, or pivot, of the axis of the body portion 22 in an axial alignment and angle of the nut 60. Figure 4 also illustrates a maximum angular misalignment between the axis of the body 22 and the nut 60, which is about 20 degrees in the exemplary embodiment, which is compensated by the fastener whose thread does not break or deforms 10 in the absence of a substantially annular depression 40. Figures 1 to 4 also illustrate a cylindrical portion of the body 70 positioned between the partially curved surface 28. of the tip portion 26 and the groovepartially annular 40 disposed around the portion of the body 20. After the portion of the body 20 is aligned substantially axially and angularly, with the hole 64 of the nut, the cylindrical body portion 79 maintains an almost axial alignment and of the portion of the body 20 in the hole 64 of the nut 60, after inserting the cylindrical portion of the body 70 into the hole 64. In one embodiment, the portion of the cylindrical body 70 has an axial dimension approximately corresponding to 1 degree of screw threads, and in other embodiments the axial dimension can be smaller or larger. However, the axial dimension of the cylindrical portion of the body 70 must be long enough to maintain the substantial alignment of the portion of the body 2-0, after the insertion of the cylindrical portion 70 thereof, into the orifice of the body. the nut 64, but should not be so long as to interfere with the initial pivot alignment of the misaligned body portion 20 as discussed above, in relation to Figures 3 and 4. Figures 1 to 4 illustrate a portion 32 of the threaded body portion 30 tapering towards the tip portion 26 of the body part 20. In one embodiment, the tapered, threaded portion 32 has an axial dimension, approximately 3 to approximately 4 degrees of the thread of the screw. The tapered threaded body portion 32 facilitates the alignment of the threads of the screw 30 with the threaded hole 64 of the nut 60, to compensate for the slight angular misalignment between the body portion 20 and the nut 60, after the insertion of the screw. the portion of the body 20 and causes the proper engagement of the threads between them. The angle of inclination ranges from approximately 10 degrees to approximately 18 degrees, and in the exemplary embodiment the inclination is approximately 14 degrees. Figure 2 illustrates at least some of the threads in the tapered threaded body portion 32 forming two separate parts, several of which are identified by the numerals 36, 37 and 38, and preferably substantially evenly separated around the circumference of the body portion 20. The separate threaded body portion compensates for a greater degree of misalignment between the body portion 20 and that of the nut 60 after insertion of the body portion and facilitates proper engagement between These will be compensated without the threads of the outgoing. Figures 1 and 2 illustrate the screw threads of the tapered, threaded body portion 32 having a flank angle greater than the flank angle of the screw threads of the unsharpened, remaining threaded portion 34.

The flank angle of the tapered, threaded body portion 32 increases toward the tip portion 26 of the body portion 20. In the exemplary embodiment, the flank angle of the threaded body portion 34 is approximately 60 degrees, and as the diameter of the portion of the threaded body 32 decreases toward the end 27 the angle of the flank increases to approximately 100 degrees. The increasing flank angle of the tapered threaded body portion 32 also facilitates the alignment of the threads of the screws 30 with the threaded hole 64 of the nut 60, further compensating for the slight angular misalignment between the body portion 20 and of the nut 60 after the insertion of the portion of the body 20 therein, and also facilitates a proper engagement between them, thus also increasing the effectiveness in the placement of the 1-a portion of the threaded body 30 with the threaded hole 64 of the nut 60. While the above description of the invention allows a person skilled in the art to make and use what is hereby considered to be the best embodiment of the invention, those skilled in the art will appreciate the possibility of making variations, combinations, modifications and equivalents of the invention without departing from its spirit and the scope of the exemplary embodiments that are They make known here. Therefore, the present invention is not limited to these embodiments but to all embodiments that are within the scope of the following claims.

Claims (12)

Claims

1. A fastener whose thread is not damaged or deformed comprising: a portion of the body having axial dimensions and an end portion, guide, with a tip portion; the threads or cords of the screw that are formed in the portion of the body part, the portion of the threaded body has a larger diameter and a smaller diameter; an end portion, guide, of the portion of the body that lacks threads or rope and that has a diameter smaller than the largest diameter of the portion of the threaded body; a tip portion of the body portion having at least one substantially curved surface; and a substantially annular groove positioned around the body portion between, at least, the substantially curved surface of the tip portion and a portion of the threaded body.

The fastener according to claim 1, wherein the end, guiding portion of the body portion is free of threads having a smaller diameter than the smaller diameter of the nut member.

The fastener according to claim 1, further comprising a cylindrical body portion positioned between at least the substantially curved surface of the tip portion and a substantially annular groove disposed around the body portion.

The fastener according to claim 3, wherein the portion of the cylindrical body has an axial dimension corresponding to approximately 1 degree of the threads of the screw.

The fastener according to claim 1, wherein the portion of the threaded body portion, close to the tip portion of the body part, has a narrow portion toward the tip portion, the screw threads of the tapered threaded body portion has a flank angle greater than the flank angle of the screw threads of the remaining threaded body portion.

6. A fastener whose thread is not damaged or deformed comprising: a portion of the body having an axial dimension and an end portion, guide, with a portion of the tip; the screw threads or cords formed in the portion of the body part, a portion of the threaded body portion close to the tip portion of the body part having a narrow or tapering portion toward the tip portion, the screw threads of the threaded, tapered body portion having a flank angle greater than the flank angle of the screw threads of the remaining threaded body portion.

The fastener according to claim 6, wherein the flank angle of the threaded, tapered body portion increases toward the tip portion of the body portion.

The fastener according to claim 6, wherein the flank angle of the remaining threaded body portion is approximately 60 degrees, and the flank angle of the tapered threaded body portion increases to approximately 100 degrees. 9-.

The fastener according to claim 6, wherein at least some of the cords or threads of the screws in the tapered threaded body portion form separate projections.

The fastener according to claim 6, wherein the portion of the threaded body has a reduction of approximately 14 degrees.

The fastener according to claim 6, wherein the tapered threaded body portion has an axial dimension between about 3 to about 4 degrees of the screw thread.

12. The fastener according to claim 6, wherein the portion of the threaded body has a larger diameter and a smaller diameter, an end portion, guiding of the body portion lacks threads and has a diameter smaller than the larger diameter of the portion of the body. threaded body, the tip portion of the body part has at least one substantially curved surface.