JPH0212634Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in a clock with an alarm, and relates to something that prevents unnecessary generation of alarm sounds or forgetting to set the alarm.

(Prior art) Conventionally, after performing an operation to turn off the alarm sound, users forget to set the alarm and panic when the alarm does not occur the next morning, or the alarm is set and left unattended and no one uses it. There is a problem where an alarm sound is generated even though the

In order to solve these problems, in the past, as in Japanese Patent Application Laid-Open No. 60-33081, it was assumed that the user was not present if the alarm sound did not stop ringing after the alarm sound was generated, and even if the alarm set time arrived thereafter, the alarm sound would not sound. A method was devised to prevent this from occurring.

(Problem that the invention aims to solve) However, according to this method, it is impossible to determine whether the user is absent unless the alarm is notified once, and if the user returns and uses the alarm after that, the alarm set switch must be reset. If the alarm is not set, the alarm will not sound, and there is a risk that the user may try to use it without knowing it.

(Means for solving the problem) The present invention uses an infrared sensor that detects infrared rays emitted from the human body in order to detect whether the user is nearby. The present invention is characterized by the addition of an operation signal control circuit that prevents the alarm sound from being generated even if the alarm set switch is in the set state when the alarm is not set. The present invention further adds an operation period detection circuit to the infrared sensor, which operates the infrared sensor only during a period when it is possible to distinguish whether the user is actually near the watch body when the alarm sound is generated, such as when sleeping, to prevent malfunction. ing.

(Embodiment) FIG. 1 is a block circuit diagram of an alarm clock according to an embodiment of the present invention.

Reference signal generator 2, frequency divider circuit 4, clock circuit 6,
The decoder/driver 8 and the display section 10 have the same configuration as a conventional digital watch. In addition, an alarm circuit 12 that generates an alarm sound when the current time measured by the clock circuit 6 reaches a set time compares an alarm memory 14 that stores the set time and the time in the clock circuit 6 with the alarm memory 14. The sound generation circuit 18 generates an alarm sound based on the coincidence output of the coincidence circuit 16, and the AND gate 20 prevents the coincidence output from being supplied to the generation circuit 18.

An operation signal from an alarm set switch 22 is input to one input of the AND gate 20 via an operation signal control circuit to be described later. This operation signal is configured so that when the alarm set switch 22 is closed, the AND gate 20 is opened, and when the switch 22 is opened, the AND gate 20 is closed.

The present invention further includes an infrared sensor 24 that detects whether a user is nearby by detecting infrared rays emitted from a human body.
The output signal of an AND gate 26 is input to the operation terminal for activating the infrared sensor 24, and the AND gate 26 is connected to the alarm set switch 22, the frequency divider circuit 4, and the clock circuit 6.
An operation period detection circuit 28 is connected which outputs an operation signal intermittently for a period determined by the output of the circuit.

On the other hand, the output signal of the infrared sensor 24 is input to the operation signal control circuit 30. This operation signal control circuit 30 transmits an operation signal of the alarm set switch 22 to the alarm circuit 1 when the infrared sensor 24 detects infrared rays emitted from the human body even once.
2, and conversely, when it cannot be detected, it blocks the supply of the operation signal. For this purpose, the operation signal control circuit 30 inputs the output of the infrared sensor 24 to the set input S, the output of the alarm set switch 22 via the inverter 34 to the reset input R, and the Q output of the FF 32 and the alarm set switch. 22 output is input,
and an AND gate 36 whose output signal is input to the AND gate 20.

FIG. 2 is a detailed circuit diagram of the operating period detection circuit 28 of FIG. 1. In this embodiment, the clock is set from a predetermined time to a time, for example, from 9:30 p.m. to 10 p.m., when a normal person comes near the clock to go to bed.
Configured to detect between the hours of 30 minutes. Therefore, as shown in the figure, this circuit 28 includes a start time detection circuit 38 that detects the operation start time from the clock circuit 6, and an end time detection circuit 4 that detects the end time.
0, an FF 46 to which the output of the start time detection circuit 38 via the one-shot multivibrator 42 is input to the set input S, and the output of the end time detection circuit 40 via the one-shot multivibrator 44 is input to the reset input R; It consists of an AND gate 48 into which the Q output signal of the FF 46, the 1-minute interval signal from the clock circuit 6, and the 1-second width signal from the frequency divider circuit 4 are input.

Therefore, this operation period detection circuit 28
A signal is output to operate the infrared sensor 24 for one second at one-minute intervals during a predetermined period of the day. If the alarm is in the set state, the infrared sensor 24 detects the infrared rays emitted from the human body during this operation, and when it detects the presence of a person, sets the FF 32 and sets its Q output to "H" and outputs an output signal. The gate 36 is opened and the operation signal of the alarm set switch 22 is supplied to the AND gate 20 in the alarm circuit 12. On the other hand, if infrared rays cannot be detected and the presence of a person cannot be detected, FF3
2 is not set, the AND gate remains closed, and the operating signal from the alarm set switch 22 is not supplied to the alarm circuit 12. Therefore, even if the alarm is in the set state, the alarm does not operate. Also, if the alarm is not set, that is, the alarm set switch 22 is open,
Since the AND gate 26 is closed, the infrared sensor 24 does not operate, and the FF 32 remains reset, so no infrared detection is performed.

(Effect of the invention) As described above, according to the invention, the infrared sensor detects whether the user is near the watch body or not and determines whether or not to actually generate an alarm sound, thereby eliminating unnecessary alarms. There is no sound, and there is no need to unset the alarm each time you are away, or set it when you want to use it again. Furthermore, since detection by the infrared sensor is performed only when necessary and for a certain period of time, unnecessary power consumption and malfunctions are reduced.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an alarm clock according to an embodiment of the present invention. FIG. 2 is a detailed circuit diagram of the operating period detection circuit of FIG. 1. 2... Reference signal generator, 4... Frequency dividing circuit, 6...
...Clock circuit, 12...Alarm circuit, 22...Alarm set switch, 24...Infrared sensor,
28... Operating period detection circuit, 30... Operating signal control circuit.

Claims (1)

[Scope of utility model registration request] a reference signal generator, a frequency dividing circuit that divides the signal from the reference signal generator, a clock circuit that clocks the current time based on the output of the frequency divider circuit, and the current time measured by the clock circuit is set. an alarm circuit that detects when the time has come and generates a notification sound;
an alarm set switch that enables the operation of the alarm circuit by external operation; an infrared sensor that detects infrared rays emitted from a human body in the vicinity of the alarm watch; an operation period detection circuit that determines the period in which the infrared sensor operates;
An operation signal control circuit that disables the operation signal of the alarm set switch when the infrared sensor does not detect the infrared rays within the period detected by the operation period detection circuit is added. A clock with an alarm.