Connecting element for two machinery components or constructional components
OwnerSiegfried Jendeinventor
Life of this patent
Estimating the term…
Abstract
A connecting element for two machinery components or constructional components is provided with a threaded portion 4 used for fastening and an anti-fatigue portion 3 arranged axially displaced to the threaded portion 4 and consisting of several elevations 5 and grooves6, with the minor diameter d.sub.3R of the grooves 6 of the anti-fatigue portion 3 being made smaller than the minor diameter d.sub.3 of the threaded portion 4. The proportion is between 80 and 100%. The pitch diameter d.sub.2R of the anit-fatigue portion 3 consisting of the elevations 5 and the grooves 6 are larger than or the same as the pitch diameter d.sub.2 of the threaded portion 4.
Claims7
An anti-fatigue connecting element comprising a head and a solid elongated shank extending from said head said shank including a threaded portion used for fastening elements together and an anti-fatigue portion positioned between said head and said threaded portion and axially displaced along said shank from the threaded portion, said anti-fatigue portion including several elevations and grooves, with the minor diameter of the grooves of the anti-fatigue portion being made smaller than the minor diameter of the threaded portion, wherein the minor diameter (.sup.d 3R) of the grooves (6) of the anti-fatigue portion (3) is between 80% and less than 100% of the minor diameter (.sup.d 3) of the threaded portion (4), and wherein the pitch diameter (.sup.d 2R) of the anti-fatigue portion (3), the pitch (P*) and the thread angle (.alpha.) substantially satisfy the equation:
- (.sup.d 2R)=(.sup.d 3R)+2/3.multidot.P*/(2 tan (.alpha./2))
- where P*=the pitch of the threads of the anti-fatigue portion and .alpha. is the thread angle.
An anti-fatigue connecting element for fastening together machinery components and the like, comprising a rectilinear shank (2) and a head member (1) mounted to one end of said shank, said shank including a helically threaded fastening portion (4) and an anti-fatigue portion (3) axially displaced from said fastening portion, said fastening portion including helical threads having a minor diameter (.sup.d 3), a pitch diameter (.sup.d 2), an outside diameter (d), and rounded recesses between adjacent ones of its threads, said anti-fatigue portion (3) of the shank including alternating elevations (5) and grooves (6) extending circumferentially about the shank with said grooves being rounded between adjacent elevations at a radius of curvature of at least as large as the radius of curvature of the rounded recesses between adjacent threads of said fastening portion, with the grooves of said anti-fatigue portion having a minor diameter (.sup.d 3R) and the elevations having an outside diameter (.sup.d R) and a pitch diameter (.sup.d 2R), said minor diameter (.sup.d 3R) of said grooves (6) of the anti-fatigue portion being between 80% and 100% of the minor diameter (.sup.d 3) of the helical threads of the fastening portion (4), and wherein the pitch diameter (.sup.d 2R) of the anti-fatigue portion (3) is at least as large as the pitch diameter (.sup.d 2) of the helical portion (4) and wherein the pitch diameter (.sup.d 2R) of the anti-fatigue portion (3), the pitch (P*) and the thread angle (.alpha.) substantially satisfy the equation:
- (.sup.d 2R)=(.sup.d 3R)+2/3.multidot.P*/(2 tan (.alpha./2))
- where P*=the pitch of the threads of the anti-fatigue portion and .alpha. is the thread angle.
An anti-fatigue connecting element for fastening together machinery components and the like, comprising a solid rectilinear shank (2) and a head member (1) mounted to one end of said shank, and shank including a helically threaded fastening portion (4) and an anti-fatigue portion (3) axially displaced from said fastening portion said fastening portion including helical threads having a minor diameter (.sup.d 3), a pitch diameter (.sup.d 2) and an outside diameter (d), said anti-fatigue portion (3) of the shank including alternating elevations (5) and grooves (6) extending circumferentially about the shank with the grooves having a minor diameter (.sup.d 3R), and the elevations (5) and grooves (6) extending circumferentially about the shank with the grooves having a minor diameter (.sup.d 3R), and the elevations having an outside diameter (.sup.d R) and a pitch diameter (.sup.d 2R), said minor diameter (.sup.d 3R) of said grooves (6) of the anti-fatigue portion being between 80% and less than 100% of the minor diameter (.sup.d 3) of the helical threads of the fastening portion (4), and wherein the pitch diameter (.sup.d 2R) of the anti-fatigue portion (3) is at least as large as the pitch diameter (2) of the helical threads of the fastening portin (4) and wherein the pitch diameter (.sup.d 2R) of the anti-fatigue portion (3), the pitch (P*) and the thread angle (.alpha.) substantially satisfy the equation:
- (.sup.d 2R)=(.sup.d 3R)+2/3.multidot.P*/(2 tan (.alpha./2))
- where P*=the pitch of the threads of the anti-fatigue portion and .alpha. is the thread angle.
Dependencies are inferred from the claim text.