anno-annual calendar

01

Jan  | Sun

02

Jan  | Mon

03

Jan  | Tue

04

Jan  | Wed

05

Jan  | Thu

06

Jan  | Fri

07

Jan  | Sat

08

Jan  | Sun

09

Jan  | Mon

10

Jan  | Tue

11

Jan  | Wed

12

Jan  | Thu

13

Jan  | Fri

14

Jan  | Sat

15

Jan  | Sun

16

Jan  | Mon

17

Jan  | Tue

18

Jan  | Wed

19

Jan  | Thu

20

Jan  | Fri

21

Jan  | Sat

22

Jan  | Sun

23

Jan  | Mon

24

Jan  | Tue

25

Jan  | Wed

26

Jan  | Thu

27

Jan  | Fri

28

Jan  | Sat

29

Jan  | Sun

30

Jan  | Mon

31

Jan  | Tue

01

Feb  | Sun

01

Mar  | Sun

01

Apr  | Sun

01

May  | Sun

01

Jun  | Sun

01

Jul  | Sun

01

Aug  | Sun

01

Sep  | Sun

01

Oct  | Sun

01

Nov  | Sun

01

Dec  | Sun

Reading the functions

The arrows next to the watch above allow you to show different dates. Reading Oechslin’s calendar quickly becomes intuitive.

Date

The 30+1 holes around the perimeter of the dial display the date with 10-minute markers serving as reference points. For example: the marker indicating 30 minutes also shows the 15th day of the month (30÷2=15). These 5-day markers allow for the date to be read at a glance and intuitively. The date only needs to be adjusted once a year on March 1st.

Weekday

The 7 holes display the weekday (counterclockwise rotation). You can choose which weekday you would like to display at the top. The interactive watch above is set to Sunday.

Month

The 12 holes display the month (counterclockwise rotation).

Day/night

One visible weekday dot indicates daytime (6am to 6pm). Two visible weekday dots indicate night time (6pm to 6am). This indication is not shown on the interactive watch above.

Time

The exact minute and second can be read using the date holes, which are spaced at 2 minute intervals. Holes mark even minutes and gaps odd minutes. The holes and gaps are exactly the same width as the minute hand.

 Ludwig Oechslin’s annual calendar module in brass.

Mechanics

What is an annual calendar?

An annual calendar is able to accurately display the number of days in every month except February. Therefore, it needs to be adjusted only once per year on March 1st.

How is Ludwig Oechslin’s annual calendar unique?

Oechslin executes his annual calendar as a gear system using only the following custom-designed parts:

  • Dial that serves as a module in the gear system (left)
  • Month disk and cog with 5 teeth, double-toothed (center top)
  • Collar with two fingers bonded to the hour rod (center)
  • Weekday disk (center bottom)
  • Date ring (right)

The month, date and weekday indications are actually inscribed directly on the front-side of the functional parts  –  an annual calendar can’t be reduced further (diagram).

How does it work?

Two additional fingers are bonded to the hour rod which drives the weekday disk and, via the 5 longer teeth on the month disk, imparts an extra impulse to the month disk on months with 30 days or less (February). The month disk receives power from the toothed date ring via the 5 tooth cog. 

What was Oechslin’s motivation for using gears?

With their turning wheels, gears lend themselves to Oechslin’s goal of displaying the date, month and weekday in analog fashion, like the hands on a watch. An analog display is more readable than a digital display or alphanumeric characters displayed in a window on the dial. Gears also allow the annual calendar function to be executed using very few parts. Fewer parts leads to higher reliability of the functions  –  and easier servicing. Finally, Oechslin’s gear system enables the date to be adjusted quickly via the crown; there is therefore no need for additional pushers like in conventional annual calendars. Oechslin enjoys the intellectual challenge of designing watches in the most technically elegant and functional manner possible.

Overview

An annual calendar watch accounts for months with 30 or 31 days. The date therefore only requires manual adjustment once per year on March 1st. Conventional annual calendar watches display the date, month and weekday using text and numbers. They use levers and springs and comprise many parts. Oechslin invested 3 years in developing a new annual calendar function comprised of just 3 additional parts (see video), because fewer parts imply fewer interactions between parts and higher reliability. All functions can easily be set using the crown.

Further information

Dimensions

42mm x 11mm (incl. crystal)

Weight

42mm titanium: 70g (incl. leather strap and buckle)

Water resistance

100m in titanium 

Case

2-part case in grade 5 titanium, designed by Ludwig Oechslin. 

Base Movement

ETA 2824-2 with 38 hours of power reserve. Manufacturer: ETA SA / Grenchen / Switzerland.

Crown

Screw-down crown designed by Ludwig Oechslin in grade 5 titanium.

Buckle and strap

Classic buckle in grade 5 titanium, designed by Ludwig Oechslin. Visible machining marks. Ecopell leather strap in dark blue, “Enzian”, or black in S/M/L/XL, handmade by Sabina Brägger.

Crystal

Sapphire crystal.

Night visibility

Swiss Super-LumiNova, applied by Monyco in La Chaux-de-Fonds/Switzerland.

Swiss made

The ochs und junior ochs line anno is entirely manufactured in Switzerland. Each watch is hand- assembled and regulated at the ochs und junior workshop in La Chaux-de-Fonds.

Warranty

The entire watch is covered by a 2-year guarantee. 

Design

Ludwig Oechslin, non-customizable. 

Order

Order via Mail [email protected] or via our homepage (shop).

Order with a 50% prepayment in accordance with the ochs und junior standard guidelines:
Payment via our homepage (stripe) or via bank transfer to our bank account:

 

Credit Suisse, Schwanenplatz 8, CH-6002 Luzern
ochs und junior AG
IBAN: CH31 0483 5039 2684 4100 0
Clearing No. 4835
Swift: CRESCHZZ80A
Account No. 0463-392684-41