JPH0544795Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to extending the battery life and improving the practical operability of a portable electronic device equipped with a water depth measurement function.

[Prior Art] FIG. 1 is a block diagram showing the configuration of a timepiece with a water depth measurement function, taking as an example an electronic timepiece that is a typical example of a portable electronic device. In the figure, the part surrounded by dotted lines is the basic configuration for water depth measurement. Water depth measurements usually take advantage of the fact that there is a linear relationship between water depth and pressure (approximately 10 meters at 1 atmosphere). Therefore, a pressure sensor is used as the sensor. In the figure, 1
is a pressure sensor, 2 is a drive circuit for driving the pressure sensor, and 3 is a signal processing circuit that processes signals from the pressure sensor. The water depth measurement circuit and the clock circuit 4 are basically independent, except that some signals are supplied from the clock circuit to the signal processing circuit. 5 is a display section for displaying water depth values, time, etc. When measuring water depth, turn switch 6.
Turn it on. Turn OFF when not measuring water depth.

Therefore, assume that a diver turns on the switch 6 in order to measure the water depth while diving. From that point on, the pressure sensor drive circuit 2, pressure sensor 1, and signal processing circuit 3 will be driven. On the other hand, in order to stop the depth measurement after the diver finishes diving,
When the switch 6 is turned off, the driving of the pressure sensor drive circuit 2, pressure sensor 1, and signal processing circuit 3 is stopped.

However, when considering actual use,
Turning switch 6 ON just before diving and turning OFF switch 6 immediately after the dive ends means:
Rare. Before diving, set switch 6.
After turning on, put on your diving gear. They may stay on the surface for a while to get used to the water temperature. At the end of the dive, after surfacing to the surface of the water, reaching the ship or land, turn off the switch. Furthermore, there may be cases where the switch is turned off after taking off diving equipment.

Also, especially after completing a dive, don't turn off the switch.
It is also possible that you forget to turn it off, and unnecessary depth measurements continue until you remember.

As described above, in actual use, unnecessary measurement time becomes considerably long. On the other hand, as can be seen from FIG. 1, the water depth measurement circuit and the clock circuit use the power supply 7 in common. The power sources used in small portable devices such as watches are small, such as silver batteries or lithium batteries, and the battery capacity is inevitably limited. In addition, the current consumption of a clock circuit is usually 0.5 to 3 μA, whereas the current consumption of a water depth measurement circuit is on the order of mA, and unnecessary depth measurement may significantly shorten battery life. There is.

Also, having to constantly worry about turning the switch on and off is a major disadvantage in use.

[Purpose] This invention solves these drawbacks,
The purpose of this is to enable the water depth measurement circuit to operate only during actual diving, thereby eliminating unnecessary current consumption and at the same time
The object of the present invention is to provide a portable electronic device with a depth gauge that does not require special attention when turning on and off.

[Summary] The portable electronic device with a depth gauge of the present invention includes a transparent electrode formed on the outer surface of a cover glass and conductively connected to the inside of the outer case through the attachment part of the cover glass and the outer case, and a conductive outer surface portion or another transparent electrode formed on the outer surface of the cover glass and spaced apart from the transparent electrode and electrically conductively connected into the outer case through the cover glass and the attachment portion of the outer case; and the conductive outer surface portion or another transparent electrode, the power to the water depth measuring circuit is controlled to be supplied or cut off depending on the presence or absence of electrical continuity between the conductive outer surface portion or another transparent electrode, and water depth measurement is performed only during diving. It is a feature.

[Examples] Hereinafter, the present invention will be described in detail based on Examples.

FIG. 2 shows the cross-sectional structure of an electronic watch with a water depth measurement function as an example of an embodiment of the present invention. In the figure, 8 is a cover glass, 9 is a transparent electrode formed on the cover glass, 10 is a movement, 11 is a metal exterior case, 12 is a display section, 13 is a contact spring that grounds the exterior case to V _DD , and 14 is a An insulating member 15 that secures waterproofness while fixing the cover glass 8 and the outer case 11;
is a conductive member for establishing an electrical connection between the transparent electrode and a detection circuit located within the movement 10 and detecting that water or seawater is in contact with the transparent electrode 9; 16 is a metal back cover, and 17 is a gasket.

Now let's think about diving using a watch with a depth measurement function like this. When diving starts, the transparent electrode 9 formed on the cover glass and the outer case 11 are electrically connected through water or seawater 18, as shown in FIG. The conduction resistance at this time is the conduction resistance R shown in FIG. Note that the transparent electrode 9 is composed of a transparent conductive member 9a and a transparent insulating member 9b.

FIG. 4 shows a switch circuit around the water depth measuring circuit in one embodiment shown in FIG. In the figure, reference numeral 11 denotes a metal outer case, which is connected to V _DD through a contact spring (FIG. 2, 13). 9 is a transparent electrode. As mentioned above, 19 is the conduction resistance R that occurs when the outer case and the transparent electrode are electrically connected through water or seawater. The transparent electrode is also connected to V _SS through a conductive member (FIG. 2, 15) with a resistance Ra that is sufficiently large compared to the conduction resistance R, and is connected to the D input of a D-flip-flop 21 through an inverter 20. Ru. A CL signal is input from a clock circuit as a clock for the D-flip-flop. The inverted output signal Q of the D-flip-flop is input to AND gate 22. 6
is the main switch, one end of the switch is connected to V _DD ,
The other end is connected to V _SS through a resistor Rb and input to the chattering prevention circuit 23 . The output of the anti-chattering circuit is input to the AND gate 22. The output of the AND gate 22 is transmitted through an N-channel transistor 23' and an inverter 24.
It is input to the N-channel transistor 25. 2
6 is a water depth measurement circuit.

Next, the operation will be explained according to the timing chart shown in FIG.

When the main switch 6 is in the OFF state, the output of the chattering prevention circuit (Fig. 5, 1) is digitally at a low level (hereinafter referred to as "L", and a high level is referred to as "H"). The output of the AND gate 22 (FIG. 5) becomes "L".
When the output of the AND gate becomes "L", the N-channel transistor 25 is turned on and the N-channel transistor 23' is turned off. Therefore, the water depth measurement circuit does not start up.

Next, when the main switch is turned from OFF to ON (timing t0 in Figure 5 6), the output of the chattering prevention circuit (Figure 5 1) changes from "L" to "H".
becomes.

The CL signal (FIG. 5, 2) is, for example, 512 Hz.
Until the time of actual diving, the conduction resistance R does not exist, and the D input of the D-flip-flop is in the "H" state (FIG. 5, 3). Therefore, the inverted output Q (fifth
FIG. 4) becomes "L". AND gate 22 has
"H" is input from the main switch, "L" is input from the D-flip-flop 21, and the output (FIG. 5) is "L". When the output of the AND gate becomes “L”, the N-channel transistor 25 turns on, and the N-channel transistor 25 turns on.
Channel transistor 23' is turned off. Therefore, the water depth measurement circuit will not start. In other words, even if the main switch is in the ON state, the metal exterior case 11 and the transparent electrode 9 are not electrically connected until the actual diving starts, so the water depth measurement circuit 26
will not start.

Next, assume that the actual diving has started. (5th
Timing of t1 in FIG. 6) At this time, the metal exterior case and the transparent electrode are electrically connected by water or seawater, and a conduction resistance R is generated. The D input of the D-flip-flop becomes “H”. This D input is read at the falling edge of the clock signal. At this time, the time delay (△t1 in FIG. 5, 6) is 1/512Hz maximum.
≒2mSEC, so there is no effect on accuracy during use. When the D input is read, the inverted output Q becomes "H". "H" is inputted to the AND gate 22 from the main switch and the D-flip-flop 21, and the output becomes "H". Therefore, the N-channel transistor 25 is turned off, the N-channel transistor 23' is turned on, and the water depth measurement circuit is activated. In other words, when the actual dive begins,
For the first time, the water depth measurement circuit will be driven.

Next, it is assumed that the dive ends and the diver emerges from the water or sea surface. (Timing t2 in FIG. 5) In this case, the electrical connection between the metal exterior case and the transparent electrode is insulated, and the conduction resistance R disappears.
The D input of the D-flip-flop becomes "L".
This D input is read at the falling edge of the clock signal. The time delay at this time (6△t2 in FIG. 5) is a maximum of 2 mSEC. Although the water depth measurement circuit will be driven needlessly during the 2m SEC, it can be said that this has no effect on the battery life. When the D input is read, the inverted output Q becomes "L". The output of AND gate 22 also becomes "L". Therefore, the N-channel transistor 25 is turned on, the N-channel transistor 23' is turned off, and the driving of the water depth measuring circuit is stopped. In other words, immediately after the dive ends,
Even if the main switch is in the ON state, the driving of the water depth measurement circuit will be stopped.

FIG. 6 shows another embodiment of the present invention regarding a transparent electrode portion. In the figure, 27 and 28 are transparent electrodes formed on the cover glass. 8 is a cover glass, 29 and 30 are conductive members, and 14 is an insulating member that fixes the cover glass 8 and the exterior case 11 and at the same time ensures waterproofness. One of the transparent electrodes 27 is connected to V _DD through a conductive member. On the other hand, 28 is connected at Ra to V _SS and via an inverter to the D input of the D-flip-flop. In this example, a conduction resistance R is formed between two transparent electrodes. Since the operation and circuit configuration are exactly the same as those of the embodiment shown in FIG. 2 shown earlier, a description thereof will be omitted here.

[Effects] As described above, according to this embodiment, the transparent electrode is formed on the outer surface of the cover glass and is electrically conductively connected to the inside of the outer case through the attachment portion of the cover glass and the outer case; A conductive outer surface portion of the outer case or another transparent electrode formed on the outer surface of the cover glass at a distance from the transparent electrode and conductively connected to the inside of the outer case through the cover glass and the attachment part of the outer case. ,
The power supply to the water depth measurement circuit is controlled to be supplied or cut off depending on the presence or absence of electrical continuity between the transparent electrode and the conductive outer surface portion or another transparent electrode, and the water depth measurement circuit is driven only during diving. It is configured like this. Therefore, unnecessary water depth measurements are not performed, and the limited battery capacity can be effectively utilized. Additionally, once the main switch is turned on, depth measurement automatically starts and stops, eliminating the need to pay special attention to turning the switch on and off, greatly improving practical operability. In other words, this improved operability allows divers who are in the special environment of being underwater to concentrate on diving, and the safety of diving is also dramatically improved.

Further, when a power source is shared between a clock circuit and a circuit for measuring water depth, the effect of low power consumption can be further obtained by adopting the configuration of the present invention. Furthermore, by using the clock signal output from the clock circuit in a circuit for measuring water depth, the circuit can be simplified.

Furthermore, since the conduction state between the transparent electrode and the conductive outer surface of the outer case or another transparent electrode is detected, it is possible to reliably detect the state of water entry. Since the transparent electrode is electrically conductively connected to the inside of the case through the part, there is no need to provide a new structure and there are few problems during assembly, so it can be manufactured at low cost.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a watch with a water depth measurement function. FIG. 2 is a diagram showing a cross-sectional structure of an embodiment of the present invention. FIG. 3 is a diagram showing the conduction resistance R generated between the transparent electrode formed on the cover glass and the metal exterior case. FIG. 4 is a diagram illustrating the circuit configuration of one embodiment of the present invention shown in FIG. 2 around a switch circuit. FIG. 5 is a diagram showing a timing chart of the circuit shown in FIG. 4. 6th
Figures a and b are views showing another embodiment of the present invention regarding the transparent electrode portion. 1... Pressure sensor, 2... Pressure sensor drive circuit, 3... Signal processing circuit, 4... Clock circuit, 5
... Display section, 6 ... Main switch, 7 ... Power supply, 8 ... Cover glass, 9 ... Transparent electrode, 9a
...Transparent conductive member, 9b...Transparent insulating member, 10
...Movement, 11...Exterior case, 12...
...Display section, 13... Contact spring, 14... Insulating member, 15... Conductive member, 16... Back cover, 17...
...Packing, 18...Water or seawater, 19...Continuity resistance R, 20...Inverter, 21...D-flip-flop, 22...AND gate, 23...
N-channel transistor, 24... Inverter, 25... N-channel transistor, 26...
... Water depth measurement circuit, 27 ... Transparent electrode, 28 ... Transparent electrode, 29 ... Conductive member, 30 ... Conductive member.

Claims (1)

[Claims for Utility Model Registration] A water depth measurement circuit comprising at least a water depth detection sensor that converts a water depth value into an electrical signal, and a signal processing circuit that converts the electrical signal from the water depth detection sensor into a desired measurement signal; A display section for displaying a water depth value based on a measurement signal of a measurement circuit, an exterior case housing the water depth measurement circuit and the display section, and a cover glass attached to the exterior case in front of the display section. A portable electronic device with a depth gauge, comprising: a transparent electrode formed on the outer surface of the cover glass and electrically conductively connected into the outer case through a mounting portion of the cover glass and the outer case; and the outer case. or another transparent electrode formed on the outer surface of the cover glass and spaced apart from the transparent electrode and electrically conductively connected into the outer case through a mounting portion of the cover glass and the outer case. and a control means for supplying or cutting off power supply to the water depth measurement circuit depending on the presence or absence of electrical continuity between the transparent electrode and the conductive outer surface portion or another transparent electrode. Portable electronic devices with meters.