Horology: time measuring systems or devices – Chronological – With power monitor
Reexamination Certificate
2000-04-11
2003-06-17
Miska, Vit (Department: 2841)
Horology: time measuring systems or devices
Chronological
With power monitor
C368S204000, C368S238000
Reexamination Certificate
active
06580665
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an electronic timepiece having a power generating function of detecting the power generating state of power generating means, thereby causing a display section to display a detection state, and more particularly to an electronic timepiece having a power generating function of detecting whether a state in which the power generating means generates power or a state in which the power generating means does not generate power, thereby causing display means to display the state.
BACKGROUND ART
There has been known an electronic timepiece including power generating means for converting an external energy such as a light energy or a mechanical energy into power to be utilized for time display.
Examples of the power generating means include power generation by a solar cell or the kinetic energy of a oscillating weight, power generation by a difference in a temperature on both terminals of a thermocouple and the like.
The electronic timepiece having such power generating means generally has storage means for storing power generated by the power generating means, for example, a secondary battery or a capacitor.
There has been practically used an electronic timepiece for displaying the storage level of the storage means (the residual storage level) by a modulated hand motion with changing a hand moving mode and the like, for example. Japanese Patent Application Laid-Open (JP-A) No. 60-185188 has disclosed an electronic timepiece for displaying the storage level by such a modulated hand motion.
Furthermore, Japanese Patent Publication (JP-B) No. 7-89154 and the like have disclosed an electronic timepiece for stopping a hand motion when the storage level is very low and for restarting the hand motion to perform time display when the storage level is recovered to a predetermined level or more by subsequent charging.
With reference to
FIG. 15
, description will be given to an electronic timepiece having a power generating function of the prior art.
FIG. 15
is a block diagram illustrating the structure of a circuit of an electronic timepiece having a power generating function of the prior art.
Storage means
720
such as a lithium ion secondary battery and control means
750
having a timing function are connected in parallel with power generating means
710
which is a solar cell. Moreover, control means
730
having a diode
732
is provided among the storage means
720
, the control means
750
and the power generating means
710
. The control means
730
serves to control the charging or storage of the storage means
720
.
The control means
750
for timing serves to move an hour hand, a minute hand and a second hand by using a stepping motor and a decelerating train wheel and is generally used for an electronic timepiece.
To the negative electrode side of the storage means
720
is connected storage level detecting means
742
for measuring a difference in an electric potential between the terminals of the storage means
720
and comparing the difference in an electric potential between the terminals with a predetermined difference in an electric potential. The detecting means
742
is an amplifier circuit for outputting a high level (1) when an input voltage is higher than 1.3 V and otherwise outputting a low level (0).
In
FIG. 15
, a signal output from the detecting means
742
is indicated as the reference numeral S
20
. The detecting means
720
decides that the storage level is sufficient when the signal S
20
is indicative of the high level. At this time, an ordinary one-second hand motion is carried out (by one-step to be performed every second). The detecting means
720
decides that the storage level is low when the signal S
20
is indicative of the low level. The hand motion to be performed at this time is a two-second hand motion (a two-step hand motion to be performed at a short interval of 2 seconds, such a hand motion which is different from an ordinary hand motion is referred to as a modulated hand motion).
In the electronic timepiece described above, when the power generating means
710
starts power generation, a current mainly flows from the power generating means
710
to the storage means
720
through the diode
732
and the storage means
720
is charged.
When the storage level of the storage means
720
reaches approximately 1.0 V which is enough to operate a step motor of the control means
750
which is not shown, the control means
750
is started so that the hand motion is started to be operated. In this case, the storage voltage of the storage means
720
has not reached 1.3 V yet. Therefore, the signal S
20
is indicative of the low level and the two-second hand motion is carried out.
When the power generation of the power generating means
710
is consecutively carried out and the storage means
720
is continuously charged, an absolute value of the difference in the electric potential between the terminals of the storage means
720
exceeds 1.3 V. When the absolute value of the difference in the electric potential exceeds 1.3 V, the signal S
20
is indicative of the high level and the hand motion is switched into the one-second hand motion in the ordinary state by the control means
750
.
Since, such an electronic timepiece detects the storage level of the storage means
720
to control the hand motion and informs a user whether the hand motion can be surely performed based on the detected storage level, it is convenient.
In the above-mentioned electronic timepiece according to the prior art, however the warning of the residual storage level of the storage means
720
by the modulated hand motion makes no difference during power generation and non-power generation. Therefore, even if it can be known that the storage means
720
is fully stored, it cannot be known whether or not the power generating means
710
generates power well. Moreover, even if the power generation is performed by the power generating means
710
, the modulated hand motion is continued until the storage level of the storage means
720
becomes predetermined level or more. Therefore, the hand motion different from the ordinary hand motion is carried out for a comparatively long period of time, so that it makes the users anxious.
For amusing, in the case where the user wants to show that his or her electronic timepiece which looks like an ordinary timepiece has a power generating function or the user wants to ascertain that the power generating means
710
is normally operated, it is impossible to meet such a user's demand.
In addition, when the electronic timepiece according to the prior art is left for a comparatively long period of time, the storage level of the storage means reaches approximately 0 so that the electronic timepiece does not perform as a timepiece. For this reason, it is necessary to cause the power generating means to function in use, thereby storing power in the storage means and then performing timing. In recent years, however, there has been required an electronic timepiece which does not have a time display function even if it is left for a longer period of time.
In order to solve the above-mentioned problem, it is an object of the present invention to provide an electronic timepiece having a power generating function which can immediately be seen as to whether or not the power generating means is set in a power generating state or a non-power generating state. Moreover, it is another object of the present invention to provide an electronic timepiece having a power generating function which can indicate the charging state of storage means. It is a further object of the present invention to provide an electronic timepiece having a power generating function which can control the level of consumed power based on the levels of power generation and storage, thereby keeping a time display function even if the electronic timepiece is left for a long period of time.
DISCLOSURE OF THE INVENTION
In order to achieve the above-mentioned object, the present invention provides an electronic timepiece having a power gener
Kamiyama Yasuo
Mafune Masao
Murakami Tomomi
Nagata Yoichi
Citizen Watch Co. Ltd.
Goodwin Jeanne-Marguerite
Kanesaka & Takeuchi
Miska Vit
LandOfFree
Electronic timepiece having power generating function does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electronic timepiece having power generating function, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic timepiece having power generating function will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3095161