Cookie Consent by Free Privacy Policy Generator

Sturmey-Archer SW Drei-Gang-Naben: Unterschied zwischen den Versionen

(→‎Springless pawls: Überschrift)
Zeile 37: Zeile 37:
Ein weiteres Merkmal der Lastverteilung auf drei Punkte war, dass die ringförmig angeordneten Bauteile sich selbst zentrierten. Das merkt man am deutlichsten bei den Kupplungsbauteilen der SW: die Mitnehmer des Zahnkranzes und dem rechtsseitigen Sperrklinkenring. Diese Bauteile haben drei passenden Kombinationen und haben gerundete Oberflächen. Unabhängig von der Kombination verteilt sich die last immer gleich. Diese gleichmäßige Lastverteilung ist und war das eigentliche Ziel.
Ein weiteres Merkmal der Lastverteilung auf drei Punkte war, dass die ringförmig angeordneten Bauteile sich selbst zentrierten. Das merkt man am deutlichsten bei den Kupplungsbauteilen der SW: die Mitnehmer des Zahnkranzes und dem rechtsseitigen Sperrklinkenring. Diese Bauteile haben drei passenden Kombinationen und haben gerundete Oberflächen. Unabhängig von der Kombination verteilt sich die last immer gleich. Diese gleichmäßige Lastverteilung ist und war das eigentliche Ziel.


==Springless pawls==
==Sperrklinken ohne Federn==


By far, the most notorious feature of these hubs, however, is the springless pawls. These little gems of irritation are free-floating, crescent shaped, hardened steel a mere 3/10ths of an inch long by 3/16ths of an inch wide. They resemble a Woodruff key, except that the normally flat surface of a Woodruff key has been curved, resembling a crescent or smile. They are used to transmit torque in one direction and allow freewheeling in the other. The freewheeling is accomplished by a rocking action imposed by the passing ramps and valleys of the right or left ball rings — it's actually quite clever and reminds one of the classic escapement mechanisms of mechanical watches and clocks. While coasting, these pawls are nearly silent to the rider, but spinning the wheel with the bike off the ground and your ears nearby will usually produce a noticeable ticking sound.
By far, the most notorious feature of these hubs, however, is the springless pawls. These little gems of irritation are free-floating, crescent shaped, hardened steel a mere 3/10ths of an inch long by 3/16ths of an inch wide. They resemble a Woodruff key, except that the normally flat surface of a Woodruff key has been curved, resembling a crescent or smile. They are used to transmit torque in one direction and allow freewheeling in the other. The freewheeling is accomplished by a rocking action imposed by the passing ramps and valleys of the right or left ball rings — it's actually quite clever and reminds one of the classic escapement mechanisms of mechanical watches and clocks. While coasting, these pawls are nearly silent to the rider, but spinning the wheel with the bike off the ground and your ears nearby will usually produce a noticeable ticking sound.
Zeile 44: Zeile 44:


Interestingly enough, this type of freewheel mechanism was used in (and predates) the original Sturmey-Archer three speed hub of 1902. The mechanism was referred to as the "Micrometer type of springless clutch", named after the company that apparently invented it3.
Interestingly enough, this type of freewheel mechanism was used in (and predates) the original Sturmey-Archer three speed hub of 1902. The mechanism was referred to as the "Micrometer type of springless clutch", named after the company that apparently invented it3.
==Clutching==
==Clutching==


15.322

Bearbeitungen