JPS641674Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electronic timepiece, and particularly to an electronic timepiece with smooth hand movement.

Advances in electronic clocks have brought about a dramatic improvement in accuracy. Furthermore, as devices become thinner, design-oriented devices become possible. . However, regarding the time display,
With the exception of tuning fork type battery clocks, the hands do not move smoothly and move in a discrete manner. In particular, in quartz watches, the hand moves every second. I think it's good because it symbolizes accuracy, but there are still many people in this world who prefer smooth movement of the hands. Several attempts have been made so far, but none have been realized. The present invention aims to provide a sweeping seconds electronic watch, particularly an electronic wristwatch, which has smooth hand movement as described above.

An object of the present invention is to obtain an electronic watch, especially an electronic wristwatch, that displays time with smooth hand movement.

Another object of the present invention is to provide an electronic timepiece, especially an electronic wristwatch, which has low power consumption and smooth hand movement in time display.

Let me explain in more detail. FIG. 1 is an explanatory diagram of the principle of the present invention. 1 is a time standard signal generator made of a crystal oscillator or the like, and 2 is a frequency divider circuit which divides the signal from the time standard signal generator to a required frequency. 3
is an auxiliary frequency divider circuit, which will be explained later, but plays a major role in the present invention. Reference numeral 5 constitutes a drive section of the display section including a vibration system for smooth movement of the hands of the display section 6. The frequency of the drive section 5 is determined by the movement of the hands on the display section.

The position of the needle on the display section 6 is detected by the detection means 7 at appropriate time intervals, and compared with the result of the auxiliary frequency divider circuit 3 by the comparator 4. Since the indicated value of the auxiliary frequency divider circuit is standard, it can be compared with this. Comparatively, if the needle position of the display section is delayed, a signal proportional to the amount of delay is output from the comparator 4, and if it is ahead, a signal proportional to the amount of advance is output from the comparator 4, and the output of the comparator is sent to the drive section. It enters the control section 8 and feeds back to the drive section 5. The time interval until the next detection is advanced or delayed by the amount fed back, so that the same time as the standard can always be displayed. This is the principle of the present invention. Many embodiments are possible based on this principle. As explained below, it will become clearer, but from the above explanation, the size of the auxiliary frequency divider circuit 3 must at least have a range that can be compared with the detection of the position of the hand on the display. Drive part 5
is required to have a function that can advance or slow down when the display section slows down.

We will further explain each part. The standard signal generator 1 can use a crystal oscillator for a quartz watch, a tuning fork oscillator for a tuning fork watch, or a barium titanate oscillator, etc., and is a general oscillation circuit. The explanation is omitted here. The frequency dividing circuit 2 may be a 1/2 frequency dividing FF circuit or a 1/3 or 1/4 frequency dividing circuit using a blocking oscillator circuit. The output frequency of Step Down is determined depending on how much time display accuracy is required.

For example, if 1 second is a 1 second signal, if 1/10 second is 1/10
It is configured to send out a signal corresponding to a seconds signal. The signal from the frequency divider circuit 2 is input to the auxiliary frequency divider circuit 3. Various configurations of the auxiliary frequency divider circuit 3 are possible and will be described later. A specific example of the display unit driving unit is shown in the second example.
As shown in the figure. The specific example shown in FIG. 2 uses the principle of a tuning fork clock in which a cantilevered spring is used as a vibrating body to rotate a pawl wheel. A magnet 11 is attached to the tip of the cantilever spring 10 and engaged with the coil 12 so as to vibrate it.

Furthermore, a cantilever spring 10, a magnet 11 and a coil 12
A self-oscillating system is formed, and the vibration period is 14
It is transmitted to the pawl wheel 13, and then to the needle. Since it is desirable for the needle to rotate smoothly, the self-excitation frequency is selected appropriately in relation to the wheel train. However, the range is defined as 10Hz to 1KHz. Since it is necessary to advance or retard the movement of the hands according to the retardation of the movement of the hands as described above, in FIG. 2, an amplitude characteristic is provided. That is, if the amplitude is not large, it is delayed, and if it is small, it is advanced. But you can also do it like this: That is, if the amplitude is large, the pawl wheel is not sent one tooth at a time, but by several teeth at a time, and if the amplitude is small, it is not sent at all or is sent occasionally, and the same effect of advancement and lag will be produced. It is desirable that both are nonlinear. The cantilever spring shown in FIG. 2 may be in the shape of a tuning fork or a rod.

Further, the tuning fork may be driven electromagnetically as shown in FIG. 2, or a piezoelectric element such as barium titanate may be used to provide the driving force. The vibration transmission is not limited to the pawl wheel, but may also be a magnetically engaged device such as a magnetic escapement.

Next, the display section and the hand position, that is, the means for detecting the indicated time will be described. FIG. 3 shows a specific example of the designated time detection means. On the dial 20, a second hand 21, a minute hand 22, and an hour hand 23 are rotating. In Figure 3,
Detection elements 24, 25, 26, 2 that detect the passage of the second hand at four locations: 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock.
7 is installed. The simplest method for this detection element is to attach a terminal to a part of the dial plate and output a signal when it comes into contact with the second hand.

FIG. 4 shows a light detection means. When the second hand crosses an optical path in which light from the lamp 28 is received by a photosensitive element 29, such as an element made of a phototransistor or a solar cell, it can be taken out as a signal from the photosensitive element. Figure 5 shows a method using an oscillation circuit, which uses the principle of a proximity switch, etc. In FIG. 5, capacitor electrode 3
When the second hand enters between 0 and 31, the capacitance changes and the oscillation frequency changes. This is taken as a signal.

Another example of FIG. 5 may be one in which the second hand is passed through the magnetic path of the inductance. In this case, oscillation can be further stopped than in FIG. 5, and it is easy to extract the signal. The number of detection elements for character detection is not limited to four;
It may be in one place, two places, three places, six places, or any number of places. Although the case of the second hand has been described above, it is of course also possible to use the minute hand.

However, as will be described later, it is generally more accurate to use the second hand.

Next, let's talk about comparator 4. Let us consider an example in which the designated time detection shown in FIG. 3 is performed at four locations, that is, every 15 seconds. In this case, returning to FIG. 1, the auxiliary frequency divider is constituted by an FF circuit as a specific example, and outputs one pulse every 15 seconds. In this case, a specific example of the comparator 4 is shown in FIG. 34, 35, 36 are flip-flops, a
b is the signal from the auxiliary frequency divider, and b is the detection means 6.
Input the signal from. 39, 40, 41, 42 are capacitors that separate the signals of inputs a and b, and FF3
This is to obtain a signal that triggers 5 and 36. 43 is a capacitor for obtaining a signal for triggering the flip-flop 34 by input b, and 44 is a capacitor for obtaining a signal for resetting flip-flop 34 by signal a.

FIG. 7 shows signal waveform relationships for explaining FIG. 6. A shows the a input signal waveform, b and d show the b input signal waveform, c shows the c output waveform, and e shows the d output waveform. Now, a case where the designated time is later than the standard time will be explained. At this time, the input signals to a and b include waveforms a and b, respectively. Since the signal A comes before the signal B, FF
The a signal passes before gate 37 is closed by 34 and triggers FF 35. . Subsequently, the FF signal 35 is reset as the signal ``b'' is input to the signal ``b'', and the output waveform shown in ``c'' in FIG. 7 is obtained as the output ``c''.
On the other hand, FF36 receives the signal A in a and FF36
The state remains unchanged. The signal ``b'' subsequently enters the signal ``b'', but since the gate 38 is blocked by the signal ``a'', it is not input to the FF 36, and the state of the output d does not change.

Next, if the indicated time is earlier than the standard time, the gate 38 is open and this signal
Trigger FF36. Subsequently, the FF 36 is reset by the signal A, and the signal E is obtained at the output d.

On the other hand, FF34 is triggered by the second waveform,
Since the gate 37 is closed, the A signal to a cannot pass through the gate 37, and the state of the FF 35 does not change. Therefore, no output waveform appears at c. That is, if the designated time is later than the standard time, an output signal proportional to the delay time can be obtained at the c terminal, and if it is ahead of the standard time, an output signal proportional to the delay time can be obtained at the d terminal. This is fed back to control the drive unit 5 in FIG.

Now, the output from the comparator 4 can be fed back to the drive section as is, as a number of pulses corresponding to the output, or integrated and fed back in the form of a voltage. Whether this should be determined depends on the configuration of the drive unit 5. Since the drive unit of the present invention is of a cantilever spring type, it is better to provide feedback in the form of a single pulse or an integrated voltage. Various embodiments are possible here.

The above description of the control system is a control system that can control the standard time indicated by the auxiliary frequency divider 3 and the indicated time indicated by the display unit 6 so that the indicated time coincides with the standard time even if either of them is advanced or delayed. What is required of the feedback drive system is that the control system can be considered as follows. Moreover, the control system is simple and it is effective in practice. In other words, the speed at which the display section hands are moved by the driving section 5 is set to be slightly faster than the standard time generated by the standard signal generating section 1, or vice versa, to be slightly slower. . In this case, although the matching accuracy is slightly deteriorated, there are the following advantages. In other words, if, for example, the control system is configured so that the hand movement by the drive unit is slightly faster than the standard time, the control system will always do the opposite of the above, that is, the control system will cause the hand movement by the drive unit to be delayed from the standard time. Just put it together. This is because if there is a delay due to a disturbance, etc., the process can proceed simply by removing the control. However, even in this case, by always applying a bias to operate the control system so that the hand movement by the drive unit is delayed, more accurate time indications can be obtained.

If the assembly is the opposite of the above case, that is, if the hand movement by the drive unit 5 is set to be slightly slower than the standard time, the same effect will be produced if the control system is assembled in the opposite manner to that described above.

Although several examples of embodiments of the present invention have been described above, embodiments of the present invention are not limited to the above-mentioned specific examples, and various embodiments are possible. According to the present invention, a cantilever spring-type motion converter having a self-excitation system whose excitation frequency can be changed is used in the drive part, and a feedback system is provided to detect the second hand position and provide feedback to the drive, making it easy to operate. This configuration enables smooth hand movement with the same precision as step hand movement. In addition, for smooth hand movement, there is no need for multi-pole synchronous motors with high power consumption, and a small cantilever spring type motion converter with low power consumption can be used, making it possible to use a low power consumption electronic watch. , especially an electronic wristwatch can be realized.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention. Figure 2 shows a specific example of the drive unit used in this invention. FIG. 3 is an explanatory diagram of the designated time detection means. FIG. 4 shows a specific example of the designated time detection means. FIG. 5 shows another specific example of the designated time detection means. Figure 6 shows a specific example of the comparison means used in the present invention. FIG. 7 shows waveforms at various parts in FIG.

Claims (1)

[Scope of utility model registration request] a standard signal generation section; a frequency division circuit that divides the frequency of the signal from the standard signal generation section; an auxiliary frequency division circuit that receives the output signal of the frequency division circuit and further divides the frequency; and a signal from the standard signal generation section. The time display section includes a cantilever spring-type drive unit that independently and smoothly moves the hands, a second hand that moves smoothly, and a time display that changes the displayed time at fixed time intervals by detecting when the second hand passes a predetermined position on the dial. Compare the result of detecting the displayed time with the output of the auxiliary frequency dividing circuit corresponding to the predetermined position, and input a signal corresponding to the advance or lag of the second hand with respect to the output of the auxiliary frequency dividing circuit. An electronic timepiece comprising a drive control section that controls retardation of the drive section, the drive section comprising a cantilever spring type motion converter having a self-excitation system capable of changing an excitation frequency depending on amplitude characteristics. .