Analog Watch

• US 20080101161A1
• Filed: 09/20/2005
• Published: 05/01/2008
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Ricoh Elemex Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Elemex Corporation (Ricoh Company Limited)
• Inventors: Satou, Hiroyuki, Imai, Toshiyuki, Hayashi, Kentarou, Tohyama, Kazuhisa, Hasegawa, Masahide, Nakagawa, Keiji
• Granted Patent: US 7,646,678 B2
• Time in Patent Office: Days
• US Class Current: 368/71
• CPC Class Codes: G04C 17/02 by electric lamps
• CPC Class Codes: G04G 9/04 by controlling light sources, e.g. electroluminescent diodes G04G9/0058 takes precedence

Abstract

Provided is a watch capable of performing digital display as well as analog display. The watch can offer digital display without posing disadvantages peculiar to a liquid crystal panel. On the other hand, the watch can reduce the restrictions in design and make the digital display larger and easier to see. The watch includes a light-shielding plate 22 on the rear side of the dial 24. In the light-shielding plate, light-transmitting holes 23 are made piercing from a front of the light-shielding plate to a rear thereof. Thin chip LEDs 17 are inserted in the light-transmitting holes, and mounted on a circuit board 16. The circuit board is placed on the rear side of the light-shielding plate. On the rear side of the circuit board, an analog movement 13 is provided, and an LED drive circuit 33 for driving the LEDs is placed. Thus, the LEDs 17 for digital display are placed on the rear side of the dial. The dial is formed so as to have an optical transmittance such that the digital display with the LEDs can be visually identified through the dial only when the LEDs are ON.

Claims

1. An analog watch, characterized by comprising:

a dial; and

LEDs for digital display placed on a rear side of the dial,

wherein the dial is formed so as to have an optical transmittance that allows digital display by the LEDs to be visually identified through the dial only when the LEDs are turned ON.

2. The analog watch of claim 1, characterized in that the dial is formed by applying a coat to a transparent material.

3. The analog watch of claim 1, characterized in that the dial is formed with a colored semitransparent material.

4. The analog watch of claim 1, characterized by further comprising:

a light-shielding plate on the rear side of the dial; and

light-transmitting holes made in the light-shielding plate so as to piercing from a front of the light-shielding plate to a rear thereof,

wherein lights from the LEDs travel through the light-transmitting holes and impinge on the dial.

5. The analog watch of claim 4, characterized in that the light-shielding plate is formed by using a plate-like resin member having a high light-shielding ability, and applying a light-diffusing coat to inner faces of the light-transmitting holes of the resin member.

6. The analog watch of claim 4, characterized in that the light-shielding plate is formed by using a plate-like resin member having a high photoreflectance and applying a light-shielding coat to a plate surface of the resin member.

7. The analog watch of claim 4, characterized by comprising:

a circuit board placed on a rear side of the light-shielding plate, on which the LEDs are mounted at locations corresponding to the light-transmitting holes;

an analog movement provided on a rear side of the circuit board;

a hand-moving shaft piercing from the circuit board through the light-shielding plate to the dial, the hand-moving shaft having a leading end exposed on a front side of the dial; and

an LED drive circuit for driving the LEDs, placed on the rear side of the circuit board.

8. The analog watch of claim 7, characterized by further comprising:

a pair of the LEDs provided so as to sandwich a central hole of the circuit board through which the hand-moving shaft pierces; and

a colon composed of the paired LEDs.

9. The analog watch of claim 8, characterized in that numeral displays composed of the LEDs in sets of seven laid out so that each set expresses a numerical character “

8,”

are allocated and placed in pairs so as to sandwich the colon between the pairs.

10. The analog watch of any of claims 7 to 9, characterized in that the LEDs are provided in one-to-one correspondence with the light-transmitting holes.

11. The analog watch of claim 10, characterized in that a light diffusion treatment is performed on the dial at least in locations corresponding to the light-transmitting holes.

12. The analog watch of any one of claims 1 to 9, characterized in that the LED drive circuit includes an LED drive module capable of turning on all the LEDs based on an external operation.

13. The analog watch of any one of claims 1 to 9, characterized in that the LED drive circuit includes an LED drive module capable of activating an additional clocking function based on an external operation.

14. The analog watch of any one of claims 1 to 9, characterized by further comprising a secondary battery used as a power source.

15. The analog watch of claim 14, characterized by further comprising a secondary coil which allows the secondary battery to be charged by electromagnetic induction.

16. The analog watch of claim 1, characterized by further comprising a control circuit for controlling an analog hands-moving pulse timing and a digital display pulse timing synchronously.

17. The analog watch of claim 16, characterized in that the digital display pulse timing is matched to the analog hands-moving pulse timing in analog time correction synchronously with start of analog hands'"'"' moving.

18. The analog watch of claim 16, characterized in that the digital display is subjected to 30-second rounding and then returned back to zero in analog time correction.

19. The analog watch of any one of claims 16 to 18, characterized in that the digital display pulse timing is synchronized and matched with the analog hands-moving pulse timing in digital time correction.

20. The analog watch of claim 1, characterized by further comprising a control circuit capable of adjusting a duty ratio,

wherein the duty ratio is a ratio of a lighting time during which the LEDs for digital display stay on with respect to a total display time during which digital display is performed.

21. The analog watch of claim 20, characterized in that the control circuit can adjust the duty ratio based on time data.

22. The analog watch of claim 20, characterized by further comprising a photosensor,

wherein the control circuit can adjust the duty ratio based on an output signal from the photosensor.

23. The analog watch of any one of claims 20 to 22, characterized in that the control circuit can adjust the duty ratio based on the optical transmittance of the dial.

24. The analog watch of any one of claims 20 to 22, characterized in that the control circuit can adjust the duty ratio based on detected voltage data.

25. The analog watch of any one of claims 20 to 22, characterized in that when the numeral displays for performing digital display are shifted by a light source break time, switched and turned on in turn, the control circuit can change the duty ratio by altering the light source break time.

26. The analog watch of claim 1, characterized by further comprising an electric circuit including:

a battery;

a control CPU that accepts supply of an electric power from the battery;

and a controlled part that accepts supply of the electric power from the battery and is made to work by the control CPU,

wherein the controlled part is provided with a charger pump, and

when the control CPU makes the controlled part work, an output of the charger pump is fed back to a power source terminal of the control CPU.

27. The analog watch of claim 26, characterized by further comprising a means capable of setting flow of electric current, the means preventing a flow from the battery and a flow from the charger pump from being mixed.

28. The analog watch of claim 26 or 27, characterized in that the controlled part is provided with an LED for digital display.