4X4 TRANSMISSION SYSTEMS. Maintaining Adhesion

4X4 TRANSMISSION SYSTEMS

Maintaining Adhesion

Nikos Loupakis deciphers the trendy 4X4 logos, 4WD, AWD and analyzes the close relationship of all-wheel drive with off-road driving.

All of us have at some point seen an I.X. immobilized in the sand in summer, next to some beach, with its two driving wheels spinning "crazily", but without being able to move the car. It is perhaps the simplest and most typical example that shows the limits of two-wheel drive systems and at the same time explains why all off-road cars have some form of four-wheel drive.. That is, a four-wheel drive system. Wheel spin is a phenomenon that occurs much more easily on dirt, in the mud, in the sand, in the snow etc. and can drive, under certain conditions, at a complete stop of the car. You see, when we have "crazy" spin of one wheel, the other is immobilized and (λόγω της βασικής λειτουργίας του διαφορικού) δεν μπορεί να μεταφέρει δύναμη στο έδαφος και να «ξεκολλήσει» το αυτοκίνητο.

Οταν η κίνηση μεταδίδεται σε όλους τους τροχούς, η δύναμη που πρέπει να «βάλει» κάθε λάστιχο στο δρόμο για να κινηθεί το αυτοκίνητο μειώνεται στο μισό και, κατά συνέπεια, η πρόσφυση χάνεται σαφώς πιο δύσκολα. Αυτό σημαίνει ότι αυξάνεται η δυνατότητα κίνησης σε επιφάνειες με χαμηλό συντελεστή τριβής, όπως είναι το χώμα και η λάσπη. Θυμίζουμε ότι το σπινάρισμα αρχίζει όταν η δύναμη που ασκεί ο τροχός στο δρόμο (για να σπρώξει το αυτοκίνητο) ξεπεράσει το όριο που καθορίζεται από την ποιότητα του εδάφους. Για να μεταφερθεί η κίνηση και στους τέσσερις τροχούς, απαιτείται η προσθήκη κάποιων επιπλέον στοιχείων στο σύστημα μετάδοσης. Aυτά είναι ένα ενδιάμεσο κιβώτιο μεταφοράς (transfer case), που μπορεί και να περιλαμβάνει ένα διαφορικό, ή κάποιος τύπος συμπλέκτη που αναλαμβάνει να μοιράσει την κίνηση στους δύο άξονες (εμπρός και πίσω). Ο τύπος της τετρακίνησης που θέλει κάποιος να πετύχει καθορίζει και τον τύπο των στοιχείων που θα προστεθούν.

Kάντε κλικ> Τύποι συστημάτων μετάδοσης της κίνησης στους τέσσερις τροχούς

continuity: trans.kathimerini.gr

Leipzig: The "little Paris" of Saxony is experiencing its own economic miracle…

Goethe loved it as "little Paris". S’ αυτή μεγαλούργησαν ο Μπαχ και ο Μέντελσον, while it was the birthplace of great personalities from the field of Letters, of Arts and Sciences, with the most famous Wagner and Leibniz.

This is where it started, in the fall of 1989, the "peaceful revolution" of the citizens of the German Democratic Republic (GDR), who with the basic slogan "We are the people" flooded the streets of the country, claiming more "freedom", contributing, so, in the fall of the "regime".

Leipzig - about her- it has always been a great commercial center, with a rich culture and a great tradition in the sciences. Despite the damages it suffered during B’ World War, but also its degradation during the period of existing socialism, take advantage, after the fall of the Wall, its comparative advantages and evolved -20 years after the unification of Germany- in a regional "capital" of the economy, of culture and letters.

It's no accident, after all, which Leipzig - has a population of just over half a million and is located in the federal state of Leipzig- recently received two highly honorable awards from equal numbers -internationally- recognized newspapers. On the one hand, the "Financial Times", who evaluated the city's economic development strategy as "excellent" and on the other hand by the "New York Times", which ranked it among the top ten cities internationally, which is worth a visit to watch its musical and artistic events.

Last week, a group of Greek journalists from Thessaloniki was in Leipzig, on the initiative of the Consulate General of Germany in Thessaloniki, and had the opportunity to visit and talk with city officials and local media representatives about the city's economic "miracle", for the past, its present and future, as well as about the relations between Leipzig and Thessaloniki, which from the 1984 they are twinned.

"With the fall of the Wall and the unification of Germany, Leipzig experienced the tragic consequences of deindustrialization. Within a short time there were barely any left 12.000 industry jobs from 115.000 that existed until then. Huge factories were closed and industrial units moved and settled in other areas. In his mid-teens 1990, the city's population declined noticeably, falling into 400.000 residents, a fact attributed to the migration of many city dwellers to urban centers in western Germany. Whole areas were turned into ghosts. Unemployment soared to 23%", said the deputy mayor of Leipzig, Andreas Miller.

continuity: …. www.kathimerini.gr

Leipzig: The "little Paris" of Saxony is experiencing its own economic miracle…

Goethe loved it as "little Paris". S’ αυτή μεγαλούργησαν ο Μπαχ και ο Μέντελσον, while it was the birthplace of great personalities from the field of Letters, of Arts and Sciences, with the most famous Wagner and Leibniz. From here it started, in the fall of 1989, the "peaceful revolution" of the citizens of the German Democratic Republic (GDR), who with the basic slogan "We are the people" flooded the streets of the country, claiming more "freedom", contributing, so, στην πτώση του «καθεστώτος».Η Λειψία -περί ης ο λόγος- it has always been a great commercial center, with a rich culture and a great tradition in the sciences. Despite the damages it suffered during B’ World War, but also its degradation during the period of existing socialism, take advantage, after the fall of the Wall, its comparative advantages and evolved -20 years after the unification of Germany- in a regional "capital" of the economy, of culture and letters. It is not accidental, after all, which Leipzig - has a population of just over half a million and is located in the federal state of Leipzig- recently received two highly honorable awards from equal numbers -internationally- recognized newspapers. On the one hand, the "Financial Times", who evaluated the city's economic development strategy as "excellent" and on the other hand by the "New York Times", which ranked it among the top ten cities internationally, που αξίζει κάποιος να επισκεφθεί για να παρακολουθήσει τα μουσικά και καλλιτεχνικά της δρώμενα.Την περασμένη εβδομάδα, a group of Greek journalists from Thessaloniki was in Leipzig, on the initiative of the Consulate General of Germany in Thessaloniki, and had the opportunity to visit and talk with city officials and local media representatives about the city's economic "miracle", for the past, its present and future, as well as about the relations between Leipzig and Thessaloniki, which from the 1984 είναι αδελφοποιημένες.«Με την πτώση του Τείχους και την ενοποίηση της Γερμανίας, Leipzig experienced the tragic consequences of deindustrialization. Within a short time there were barely any left 12.000 industry jobs from 115.000 that existed until then. Huge factories were closed and industrial units moved and settled in other areas. In his mid-teens 1990, the city's population declined noticeably, falling into 400.000 residents, a fact attributed to the migration of many city dwellers to urban centers in western Germany. Whole areas were turned into ghosts. Unemployment soared to 23%", said the deputy mayor of Leipzig, Αντρέας Μίλερ.συνέχεια: …. www.kathimerini.gr