Quartz movement: operation and history
of reading - words
Bringing a precision unequalled in the history of time "capture" and display, the quartz movement has caused a revolution in the watch and clock industry. Turning our lives upside down, it was now finally possible to have the exact time in our daily lives.
To understand to what extent this quartz movement has revolutionized the world we will see in this article:
- How a quartz movement works.
- The history of the quartz movement.
- The quartz movement vs. mechanical movement.
1) How a quartz movement works
1) Functioning and properties of quartz
The operation of a mechanism using a quartz movement is very simple: When stimulated electrically, quartz starts to oscillate at a precise frequency due to its piezoelectric properties. This well-calibrated frequency lasts exactly one second and is therefore very easily used by watchmakers to design extremely precise clocks. To achieve this coveted frequency, the quartz is cut into a lamella which is then placed in a tin tube to protect it.
How it works and how it is used in watchmaking also and above all depends on the display mode, digital or analogue.
2) Quartz movement and digital display
It is very simple to operate a clock or watch with a digital display using the properties of quartz. The power source is the battery, which will send a pulse to the quartz. This pulse will create vibrations that are transmitted to the chip installed in the mechanism. This chip will then decode all the vibrations received and tell the display to increment by one sound every second and then by one minute every 60 seconds, etc...
🕒 Discover our digital wall clocks using this quartz movement 🕒
digital wall clock quartz movement
3) Quartz movement and analog display
For the analog display this is a little longer and more complex. The battery, as with the digital display, will send a pulse to the quartz which will make it vibrate and send it to the chip. The chip this time will send an electric pulse to a coil belonging to the stepper motor.
4) The stepper motor
Marius Lavet is the inventor of the stepper motor in 1936, this motor is made up of :
- a coil
- a stator
- a magnetic rotor
When a magnet is rotated in a cylinder, an electric current is produced. The reverse also works on the same principle, i.e. inducing an electric current in a coil will then produce an electric current.
The stepper motor works on this principle! The rotor is magnetized, we will then introduce an electric current into the coil which will create a magnetic current in the stator resulting in a half rotation of the rotor. An electric current is then sent in the opposite direction in order to reverse the polarity in the stator which will make the rotor make a full rotation. The movement of the rotor is then transmitted to the gears which makes the quartz mechanism work.
Bonus: If you mount a stator upside down on a clock or watch it will run upside down.
2) History and invention of the quartz movement
1) Creators and first objects
The piezoelectric effect of quartz was invented, or rather discovered, by two French brothers: Pierre and Jacques of the very famous Curie family (world-famous in particular thanks to the work carried out by Pierre and his wife Marie Curie on radioactivity).
This piezoelectric effect appears when certain crystals are pressed (in our case quartz), this makes electricity circulate inside these crystals. The reverse is also true: if electricity is passed through quartz, it will vibrate back and forth. The scientific definition of piezoelectricity is as follows:
Piezoelectricity (also called the piezoelectric effect) is the appearance of an electrical potential (a voltage, in other words) on the sides of a crystal when you subject it to mechanical stress (squeezing).
In practice, the crystal becomes a kind of tiny battery with a positive charge on one side and a negative charge on the other side; current flows if we connect the two sides together to make a circuit. In the inverse piezoelectric effect, a crystal is subjected to mechanical stress (shape deformation) when a voltage is applied to its opposite faces.
inventor quartz movement
2) Mass marketing and use
In 1927 Waren Marrison and J.W. Horton of Bell Laboratories presented the first clock that worked with a quartz movement: the Crystal clock.
crystal clock bell laboratories
Being the size of a cabinet, this first quartz clock worked by using the oscillation of the quartz caused by piezoelectricity, this electrical oscillation allows to create a very precise signal keeping the same frequency. This makes it possible to count the seconds and thus to create extremely precise clocks and watches.
The first watch working with this quartz mechanism was built in 1927 by Seiko in December 1969. Because of its simplicity of creation, its precision and its lower cost, the quartz movement quickly became the most widely used element in watches and clocks. Moreover, almost all our wall clocks work with a quartz movement. This first watch was extremely expensive when it came out, having such a precise watch was a sign of great wealth at that time.
3) Other objects using quartz
There are nowadays countless everyday objects using quartz movement. Initially all objects used as timekeepers: clocks, wristwatches, even some clocks with pendulum clocks use a quartz movement to keep the aesthetics of the clock while optimizing the reliability of the time display. The chronometer also uses a quartz movement. Because of its piezoelectric effect and low cost, quartz is widely used to make oscillators. Many other objects are made with this mineral, the world production of quartz for electronic purposes amounts to two billion each year.
3) Quartz movement vs. mechanical movement
We all know that a clock keeps and displays time, but have you ever wondered how it does it? The simplest clock you can make is probably a talking clock. If you count the seconds by repeating a sentence that takes exactly one second to say (like "elephant one", "elephant two", "elephant three"...), you'll see that you can keep time fairly accurately. Give it a try. Say your elephants from one to sixty and see how you keep time for more than a minute, in relation to your watch. Not bad, eh? Problem is, most of us have better things to do all day than say "elephant." That's why we're glad we invented clocks.
counting elephants to tell the time.
1) The mechanical movement
The first clocks used mechanical movements before the appearance of the quartz movement. In the watch industry at that time, most clocks used pendulum clocks to keep time. A pendulum is a long rod or weight on a string that swings back and forth. In 1583, the Italian physicist Galileo Galilei (1564-1642) discovered that a pendulum of a certain length always takes the same amount of time to swing back and forth, regardless of its weight or size. He realized this by watching a huge lamp swing on a chain from the ceiling of the cathedral of Pisa in Italy, and using his pulse to time its movement back and forth. In a clock, the function of the pendulum is to adjust the speed of the gears (toothed wheels with teeth cut into their edges). The speeds count the number of seconds that pass and convert them into minutes and hours, which are displayed on the hands that sweep the dial. In other words: the gears of a clock only count the elephants. The open case of a large grandfather clock showing the pendulum swinging inside. You can make a pendulum by attaching a weight to a piece of string. If the string is about 25 cm (10 inches) long, the pendulum swings back and forth about once a second. Shorter strings will swing faster and longer strings will swing slower.
Moreover, cuckoo clocks use this mechanism, for more information please read our article on the origins and operation of cuckoo clocks.
2) Limitations of this movement
The problem with a clock using mechanical mechanisms such as a pendulum clock is that the continuous pendulum will stop. Air resistance and friction will soon exhaust its energy and stop it. This is why pendulums have springs. About once a day, you wind a spring inside the clock to store the potential energy needed to keep the pendulum running for the next 24 hours. As the spring unwinds, it powers the gears inside the clock. Through a tilting mechanism called the escapement, the pendulum forces the gears to rotate at a precise speed, and this is how the gears keep time. A pocket watch is obviously too small to have a pendulum inside, so it uses a different mechanism. Instead of a pendulum, it has a pendulum that rotates first in one direction and then in the other, controlled by an escapement much smaller than that of a pendulum.
3) Advantages of the quartz movement
Clocks that work with a quartz movement solve all these problems. They are battery-powered and, because they use so little electricity, the battery can often last for several years before you need to replace it. They are also much more accurate than pendulum clocks. Quartz watches work in a very different way from ordinary clocks and watches. They still have gears inside them to count the seconds, minutes and hours and sweep the hands around the clock face. But the gears are regulated by a tiny quartz crystal instead of an oscillating pendulum or a moving balance. Gravity isn't in the gears at all, so a quartz clock tells time both when you're climbing Everest and when you're at sea.