Horology: time measuring systems or devices – Chronological – With power monitor
Reexamination Certificate
2000-03-22
2001-10-30
Roskoski, Bernard (Department: 2859)
Horology: time measuring systems or devices
Chronological
With power monitor
Reexamination Certificate
active
06310834
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a battery residual quantity or capacity display for an electronic apparatus having a battery as a power source and with an ultrasonic motor as a driving source, and more particularly relates to a battery residual quantity or capacity display for an electronic watch having an ultrasonic motor as a driving source of a calendar display mechanism.
2. Description of the Related Art
Although only about ten years has passed since the ultrasonic motor was developed, since it has desirable features including a small size, light weight, high output, excellent controllability, small operating sound, and the like, it has already been adopted in various industrial fields. Particularly, due to the feature of the small size and light weight without using a winding, it has been adopted in an electronic apparatus having a battery as a power source. Inventors of the present invention have already put an electronic watch adopting an originally developed ultrasonic motor as a driving source of a calendar display mechanism to practical use.
Irrespective of whether the ultrasonic motor is made a driving source or not, an electronic apparatus with a battery as a power source, such as an electronic watch, is generally provided with a battery residual quantity display device. This is for notifying the user of the end of the battery life before it is exhausted so that the exchange of the battery can be suitably carried out.
A conventional battery residual quantity display device used for an electronic apparatus with a battery as a power source is constructed such that a reference value is compared with a detected voltage level of a battery voltage by a comparator to judge whether the battery life coming to an end, and the battery life is displayed. The reference value is a voltage corresponding to a drivable voltage of the electronic apparatus, and the detected voltage level is a divided voltage obtained from the battery voltage by a voltage dividing circuit formed by a plurality of voltage dividing resistors.
However, in such a conventional battery residual quantity display device, there is a problem in that since the drivable voltage of an apparatus must be set in view of fluctuation of comparators and voltage dividing resistors, there often occurs a case where it is judged that the battery life come to an end though it can be actually used, and resulting in the problem that the usable period or usable range of the battery becomes short. In brief, there is a problem in that the conventional battery residual quantity display device must display not an actual battery life, but an apparent battery life with a rather larger allowance than desired. Besides, in a conventional battery residual quantity display device in which not only a battery life is displayed but also a battery residual quantity is always displayed, since detected voltage levels must be set by many voltage dividing circuits, there is also a problem in that a circuit scale becomes large.
Moreover, with respect to a battery residual quantity display of an electronic apparatus having an ultrasonic motor as a driving source, in addition to the foregoing problem, there is also a problem as to a large driving current. That is, since a voltage drop occurs by the large driving current in the driving of the ultrasonic motor, when circuit design is made for the battery residual quantity display device using the voltage dividing circuit and the comparator, there is also a difficulty that this voltage drop must also be taken into consideration.
SUMMARY OF THE INVENTION
A first object of the invention is to provide an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, in which a state exceedingly close to an actual battery life is detected and that is displayed.
A second object of the invention is to provide an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, in which a circuit structure is simplified as compared with a conventional apparatus and a battery residual quantity, not to mention a battery life, can be always displayed.
A third object of the invention is to provide an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, in which an alarm can be issued when it is judged that a battery life has come to an end.
A fourth object of the invention is to provide an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, in which the ultrasonic motor is made to be hindered from operating when it is judged that a battery life has come to an end.
A fifth object of the invention is to provide an electronic watch having an ultrasonic motor as a driving source of a calendar display mechanism, in which a circuit structure is simplified, while a state exceedingly close to an actual battery life is detected and that is displayed, and a battery residual quantity or capacity can be always displayed.
In order to achieve the first and second objects, in an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, a battery residual quantity or capacity display device includes a battery residual quantity display unit, a revolution speed detector for detecting a revolution speed of the ultrasonic motor, a memory in which comparison data are stored, and a control circuit for comparing the revolution speed with the comparison data and for driving the battery residual quantity display unit on the basis of the comparison result.
In order to achieve the third object, in an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, a battery residual quantity display device includes a battery residual quantity display unit, a revolution speed detector for detecting a revolution speed of the ultrasonic motor, a memory in which comparison data are stored, and a control circuit for comparing the revolution speed with the comparison data and for driving the battery residual quantity display unit on the basis of the comparison result, and the electronic apparatus includes an alarm controlled by the control circuit when the revolution speed coincides with a minimum effective battery residual quantity value.
In order to achieve the fourth object, in an electronic apparatus having a battery as a power source and an ultrasonic motor as a driving source, a battery residual quantity display device includes a battery residual quantity display unit, a revolution speed detector for detecting a revolution speed of the ultrasonic motor, a memory in which comparison data are stored, and a control circuit for comparing the revolution speed with the comparison data and for driving the battery residual quantity display unit on the basis of the comparison result, wherein the control circuit prohibits driving of the ultrasonic motor when the revolution speed coincides with a minimum effective battery residual quantity value.
In order to achieve the fifth object, in an electronic watch having an ultrasonic motor as a driving source of a calendar display mechanism, a battery residual quantity display device includes a battery residual quantity display unit, a revolution speed detector for detecting a revolution speed of the ultrasonic motor, a memory in which comparison data are stored, and a control circuit for comparing the revolution speed with the comparison data and for driving the battery residual quantity display unit on the basis of the comparison result. The revolution speed detector is realized by a detector which detects a rotation period of a rotor of the ultrasonic motor or a constituent member of a transmission mechanism for transmitting a rotational force to the calendar display mechanism.
REFERENCES:
patent: 4316274 (1982-02-01), Ushikoshi
patent: 5835456 (1998-11-01), Farine et al.
Adams & Wilks
Roskoski Bernard
Seiko Instruments Inc.
LandOfFree
Electronic apparatus with ultrasonic motor as driving source 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 apparatus with ultrasonic motor as driving source, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic apparatus with ultrasonic motor as driving source will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2571297