received by the International Bureau on 14 December 2015 (14.12.15)

Simulation device (1) comprising:

- a clock face (40) comprising a see-through area (W), said see-through area (W) having an essentially hourglass-like shape;

- a first disc (10) arranged below the clock face (40); and

- a second disc (20) arranged below the first disc (10),

characterized in that:

- said first disc (10) and said second disc (20) are rotatably mounted about a common center axis (X);

- the first disc (10) comprises:

- a first disc see-through area (Wl);

- a first disc bright contrast area (LI); and

- a first disc dark contrast area (Dl);

- the second disc (20) comprises:

- a second disc bright contrast area (L2); and

- a second disc dark contrast area (D2);

- during operation of the simulation, device (1), said first disc (10) and said second disc (20) are rotatable in opposite directions with respect to each other at essentially identical rotational speeds;

- the first disc bright contrast area (LI); the first disc dark contrast area (Dl); the second disc bright contrast area (L2) and the second disc dark contrast area (D2) are configured such that, during operation of the simulation device (1), their exposed parts through said see-through area (W) of the clock face (40) respectively through the first disc see- through area (Wl) of the first disc (10) simulate an animated hourglass' flow of substance such as sand.

A simulation device (1) according to claim 1

characterized in that said hourglass-like shape has two perpendicular axes of reflectional symmetry (SymH, SymV), said center axis (X) being perpendicular to a plane defined by the two axes of reflectional symmetry (SymH, SymV) and intersecting said plane at the intersection point (X0) of said two axes of reflectional symmetry. 19

A simulation device (1) according to claim 1 or 2

characterized in that said first disc (10) is centrally symmetric through its first disc center point (XI) situated on said center axis (X) and said second disc (20) is centrally symmetric through its second disc center point (X2) situated on said center axis (X) so that a sand heap (SH) respectively sand funnel (SF) of said animated hourglass have

complementary shapes.

A simulation device (1) according to claim 3

characterized in that:

- the first disc bright contrast area (LI) is at least partially delimited by a first disc bright primary curve (L1PC) extending from a center area of the first disc (10) to the periphery of a first plate circle (CI) having its center at said first disc center point (XI) and a diagonal essentially identical to the height of said hourglass-like shape of the see-through area (W) of the clock face (40);

- the first disc dark contrast area (Dl) is at least partially delimited by a first disc dark primary curve (D1PC) extending from a center area of the first disc (10) to the periphery of said first plate circle (CI), the first disc dark primary curve (D1PC) being arranged centrally symmetrical with respect to said first disc bright primary curve (L1PC);

- the first disc see-through area (Wl) is defined by said first plate circle (CI) excluding the first disc bright contrast area (LI) and the first disc dark contrast area (Dl);

A simulation device (1) according to claim 4

characterized in that:

- the second disc bright contrast area (L2) is at least partially defined by:

- a second disc bright curve (L2C) of essentially identical shape but reflectionally symmetrical to the first disc bright primary curve (L1PC) and

- a second plate circle (C2) having its center at said second disc center point (X2) and a diagonal essentially identical to the height of said hourglass-like shape of the see-through area (W) of the clock face (40); 20

- the second disc dark contrast area (D2) is at least partially defined by:

- a second disc dark curve (D2C) of essentially identical shape but reflectionally symmetrical with the first disc dark primary curve (LIPC) and

- the second plate circle (C2).

A simulation device (1) according to claim 5

characterized in that:

- the first disc bright primary curve (LIPC) and the first disc dark primary curve (D1PC) extend from said first disc center point (XI); and

- the second disc bright curve (L2C) and the second disc dark curve

(D2C) extend from said second disc center point (X2).

A simulation device (1) according to one of the claims 4 to 6

characterized in that:

- the first disc bright contrast area (LI) is further delimited by:

- a first disc bright secondary curve (L1SC) extending from a remote end of the first disc bright primary curve (LIPC); and

- a first disc bright tertiary curve (L1TC) connecting the first disc bright secondary curve (L1SC) with the first disc bright primary curve (LIPC);

- the first disc dark contrast area (Dl) is further delimited by:

- a first disc dark secondary curve (DISC) extending from a remote end of the first disc dark primary curve (D1PC); and

- a first disc dark tertiary curve (D1TC) connecting the first disc dark secondary curve (DISC) with the first disc dark primary curve (D1PC).

A simulation device (1) according to claim 5 or 6

characterized in that:

- the first disc bright primary curve (LIPC);

- the first disc dark primary curve (D1PC);

- the second disc bright curve (L2C); and

- the second disc dark curve (D2C) 21

are each semicircles with a radius equal to or greater than the radius of said first plate circle (CI) respectively said second disc circle (C2) wherein :

- said first disc bright primary curve (L1PC) and said first disc dark

primary curve (D1PC) expand from said first disc center point (XI) in a direction in which the first disc (10) is rotatable in operation; and

- said second disc bright curve (L2C) and the second disc dark curve (D2C) expand from said first disc center point (XI) in a direction in

^• which said second disc (20) is rotatable in operation,

9. A simulation device (1) according to claim 7

characterized in that the first disc bright secondary curve (L1SC) and the first disc dark secondary curve (DISC) is each a semicircle with a radius less than the radius of said first disc bright primary curve (LI PC) respectively first disc dark primary curve (D1PC).

10. A simulation device ( 1) according to claim 9

characterized in that the first disc bright tertiary curve (LITC) and the first disc dark tertiary curve (DITC) is each a straight segment extending from said first disc center point (XI) to an end of the first disc bright secondary curve (L1SC) respectively the first disc dark secondary curve (DISC).

11. A simulation device ( 1) according to any of the claims 5 to 7

characterized in that:

- the first disc bright primary curve (L1PC);

- the first disc dark primary curve (D1PC) ;

- the second disc bright curve (L2C); and

- the second disc dark curve (D2C)

is each a spiral, in particular a logarithmic or Archimedean spiral or an involute,

wherein:

- said first disc bright primary curve (L1PC) spiral and said first disc dark primary curve (D1PC) spiral expand from said first disc center point 22

(XI) in a direction in which the first disc (10) is rotatabte in operation; and

- said second disc bright curve (L2C) spiral and the second disc dark curve (D2C) spiral expand from said first disc center point (XI) in a direction in which said second disc (20) is rotatable in operation.

12. A simulation device (1) according to claim 11 as dependent on claim 7 characterized in that:

- the first disc bright secondary curve (L1SC) and the first disc dark

secondary curve (DISC) is each a circular arc of said first plate circle

(CI); and

- the first disc bright tertiary curve (L1TC) and the first disc dark tertiary curve (D1TC) is each a spiral, in particular a logarithmic or

Archimedean spiral or an involute, extending from said first disc center point (XI) to an end of the first disc bright secondary curve (L1SC) respectively the first disc dark secondary curve (DISC).

13. A simulation device (1) according to one of the preceding claims,

further comprising a bright contrast hand (SOL), which:

- is positioned above the discs (10, 20);

- is rotatably mounted about said center axis (X);

- has a length essentially equal to the radius of the plate circles (CI, C2);

- is configured such that, during operation of the simulation device (1), it points towards a bright sand heap (SH) of said animated hourglass in order to simulate a stream of bright of substance such as sand of an hourglass.

14. A simulation device (1) according to claim 13

characterized in that the bright contrast hand (50L) is essentially identical in appearance - such as color, texture, etc. - as the bright contrast areas (LI, L2) of the discs (10, 20).

15. A simulation device (1) according to one of the preceding claims,

further comprising a dark contrast hand (50D), which:

- is positioned above the discs (10, 20); 23

- is rotatably mounted about said center axis (X);

- has a length essentially equal to the radius of the plate circles (CI, C2);

- is configured such that, during operation of the simulation device (1), it points towards a dark sand heap (SH) of said animated hourglass in order to simulate a stream of dark substance such as sand of an hourglass.

16. A simulation device (1) according to claim 13

characterized in that the dark contrast hand (50D) is essentially identical in appearance - such as color, texture, etc. - as the dark contrast areas (Dl, D2) of the discs (10, 20).

17. Clock in particular a wrist watch comprising a simulation device (1)

according to any of the claims 1 to 16 and a clock movement, preferably a mechanical movement configured to operate the simulation device (1), by rotating said first disc (10) and said second disc (20) in opposite directions with respect to each other at essentially identical rotational speeds and preferably also actuating said bright contrast hand (50L) and/or dark contrast hand (50D).