JP2006250881A - Time switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein a frequency of a reference clock is fluctuated in response to fluctuation of an ambient temperature to generate a time error, so as not to output a drive control signal at an accurate time as a result thereof. <P>SOLUTION: This time switch 10 having a control circuit 18 for outputting the drive control signal for drive-controlling a load equipment, when the current time reaches a timer set time, has a temperature compensation type reference clock circuit 11 for compensating a frequency of the reference clock with respect to a change of the current temperature, and a clocking counter circuit 12 for outputting a counter signal, based on the reference clock from the temperature compensation type reference clock circuit, and the control circuit clocks the current time by a second unit, based on the counter signal from the clocking counter circuit 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention sets current time counting means for measuring the current time based on a reference clock, timer time setting means for setting a timer time, and current time measured by the current time counting means is set by the timer time setting means. For example, the present invention relates to an industrial time switch having a control means for outputting a drive control signal for driving and controlling a load device such as a preheat system when the timer time is reached.

  Conventionally, as such a time switch, a current time measuring means for measuring the current time based on a reference clock, a timer time setting means for setting a timer time, and a current time measured by the current time measuring means are set as a timer time. When the timer time set by the means is reached, the control means outputs a drive control signal for driving and controlling a load device such as a preheat system.

  FIG. 9 is a block diagram showing a schematic configuration inside the preheat system using the time switch.

  A preheating system 100 shown in FIG. 9 includes a heater 102 that heats the inside of the reflow furnace 101, a temperature sensor unit 103 that detects a room temperature inside the reflow furnace 101, and a solid state relay that turns on / off the power supply to the heater 102. (Hereinafter, simply referred to as SSR) 104 and a temperature regulator 105 that controls ON / OFF driving of the SSR 104 based on the current indoor temperature detected by the temperature sensor unit 103.

  The time switch 110 is connected to the temperature controller 105 in the preheat system 100, for example, a preheating start time is set in advance by a setting unit, and the current time is set based on a reference clock generated by a built-in clock circuit. When the current time reaches the preheating start time, a drive control signal is output to the temperature controller 105, which is a load device, to turn on the temperature controller and execute the heating operation of the heater.

According to the preheating system 100 using such a conventional time switch 110, when the current time reaches the preheating start time, a drive control signal is output to the temperature controller 105 to start the preheating operation of the heater 102. Therefore, the inside of the reflow furnace 101 can be preheated before the work start time.
Japanese Patent Laid-Open No. 2001-242943 (see abstract, FIG. 1 and FIG. 2)

  However, according to such a prior art time switch 110, the reference clock is generated by the built-in clock circuit, the current time is measured based on the reference clock, and the current time is set to the preheating start time (timer setting time). When it reaches, a drive control signal is output to the temperature controller 105 to perform the preheating operation of the heater 102. However, the internal power supply due to the temperature change in the surrounding environment of the time switch 110 and the energization / non-energization of the time switch As shown in FIG. 10, when the environmental temperature varies greatly, such as the difference in the amount of heat generated in the unit, the variation in internal heat value due to ON / OFF of the load drive built-in relay, and the variation in internal heat value due to the magnitude of the current flowing to the load device In addition, the oscillation frequency of the reference clock varies greatly. Since the time error also increases, the output of the drive control signal to the temperature controller 105 is delayed, so that the preheating operation of the heater 2 is also delayed, and the subsequent work start time is also delayed. There is a risk that the work efficiency of the machine will deteriorate.

  Similarly, when the conventional time switch 110 is used in a chime output system, when the current time reaches a preset chime time, the time switch 110 outputs a chime sound from the audio device from the speaker. Therefore, the drive control signal is output to the chime output system. However, as described above, when the environmental temperature fluctuates greatly, the frequency of the reference clock also fluctuates greatly. Using this reference clock, the current time is measured. When this is executed, a large time error occurs, so that a chime sound for informing the user of the accurate time may be delayed and output.

  Similarly, when the conventional time switch 110 is employed in the lighting cultivation system, on the time switch 110 side, for example, when the current time reaches a preset lighting lighting time, the lighting device in the greenhouse is turned on. When a control signal is output, for example, when the current time reaches a preset illumination extinction time, a drive control signal for extinguishing a lighting fixture that is lit is output, but when the environmental temperature fluctuates greatly as described above, The frequency of the reference clock also fluctuates greatly, and if a timekeeping operation of the current time is executed using this reference clock, a large time error occurs, so there is a delay in the time to turn off the luminaire, for example, and there is an amount of solar radiation Nevertheless, there is a possibility that useless lighting of the lighting fixtures may increase.

  The present invention has been made in view of the above points, and an object of the present invention is to be able to accurately output a drive control signal to a load device when the timer set time is reached even if the environmental temperature fluctuates. To provide a switch.

  In order to achieve the above object, the time switch of the present invention includes a current time measuring means for measuring a current time based on a reference clock, a timer time setting means for setting a timer time, and a current time measured by the current time measuring means. When the time reaches the timer time set by the timer time setting means, the time switch has a control means for outputting a drive control signal for driving and controlling the load device, and generates the reference clock and outputs the current temperature A temperature-compensated reference clock generating means for compensating frequency fluctuations of the reference clock with respect to the change of the current clock, the current time measuring means based on the reference clock generated by the temperature-compensated reference clock generating means, The current time was measured.

  In the time switch of the present invention, the temperature-compensated reference clock generating means stores a compensation value storage means for storing a compensation value for compensating frequency fluctuations of the reference clock for each temperature, and a temperature detecting means for detecting a current temperature. The clock generation means for generating the reference clock and the compensation value corresponding to the current temperature detected by the temperature detection means are read from the compensation value storage means, and generated by the clock generation means based on the compensation value. Temperature compensation means for compensating for frequency fluctuations of the reference clock.

  In the time switch according to the present invention, the current time counting means counts the reference clock generated by the temperature-compensated reference clock generation means, and the counter signal is output when the count number of the reference clock reaches a predetermined count number. Counter means for outputting, correction value storage means for storing a correction value for correcting the predetermined count number, and a count for correcting the predetermined count number in the counter means based on the correction value stored in the correction value storage means Number correction means, and the current time is measured in predetermined units based on the counter signal.

  The time switch of the present invention compares the reference clock generated by the temperature-compensated reference clock generating means with an ideal reference clock, calculates a correction value for correcting a time error based on the comparison result, and calculates the calculated value. The corrected value is stored and updated in the correction value storage means.

  The time switch according to the present invention corresponds to a preheating system in which the load device varies the heater temperature in the reflow furnace, and the control means sets the current time measured by the current time counting means to the timer time setting means. When the set timer time is reached, a drive control signal for driving and controlling the preheat system is output.

  The time switch according to the present invention corresponds to a notification sound output system in which the load device acoustically outputs a notification sound, and the control means uses the timer time setting means to measure the current time measured by the current time measurement means. When the set timer time is reached, a drive control signal for driving and controlling the notification sound output system is output.

  The time switch of the present invention corresponds to an illumination system in which the load device turns on or off the illumination, and the control means sets the current time measured by the current time measuring means by the timer time setting means. When the timer time is reached, a drive control signal for driving and controlling the illumination system is output.

  According to the time switch of the present invention configured as described above, the reference clock is generated and the temperature compensation type reference clock generating means for compensating the frequency variation of the reference clock with respect to the change of the current temperature is provided. Since the current time is measured based on the reference clock generated by the compensation type reference clock generation means, the accurate current time can be measured even if the environmental temperature fluctuates. When the time is reached, a drive control signal to the load device can be output.

  According to the time switch of the present invention, for each temperature, the compensation value for compensating the frequency variation of the reference clock is stored, the compensation value corresponding to the current temperature is read, and the frequency variation of the reference clock is based on this compensation value. Therefore, even if the environmental temperature fluctuates, the correct current time can be measured.

  According to the time switch of the present invention, there is provided counter means for counting a reference clock and outputting a counter signal used for measuring the current time in a predetermined unit when the count number of the reference clock reaches a predetermined count number. Then, the correction value for correcting the predetermined count number is stored in the correction value storage means, and the predetermined count number in the counter means is corrected based on the correction value stored in the storage. It is possible to absorb time errors due to product variations of the clock generation means.

  According to the time switch of the present invention, the actual reference clock of the temperature-compensated reference clock generating means is compared with the ideal reference clock, and a correction value for correcting the time error is calculated based on the comparison result. Since the corrected value is stored and updated in the correction value storage means, it is possible to absorb time errors due to product variations in the temperature-compensated reference clock generating means.

  According to the time switch of the present invention, since it is adopted in the preheating system and the current time reaches the timer time, for example, a drive control signal for driving and controlling the preheating system is output in order to start the preheating operation of the heater. Thus, the preheating operation of the heater can be started at an accurate time, and as a result, the work can be smoothly advanced without delaying the subsequent work start time.

  According to the time switch of the present invention, for example, it is adopted in a notification sound output system such as a chime output system, and when the current time reaches the timer time, a drive control signal for driving and controlling the chime output system so as to output a chime sound. Since the chime sound is outputted as sound according to the timer time, the user can be notified of the exact time.

  According to the time switch of the present invention, a drive control signal for driving and controlling the lighting cultivation system, for example, to turn off or turn on the lighting fixture when the current time reaches the timer time, for example, in a lighting system such as a lighting cultivation system. Is output, so that the luminaire can be turned on or off at an accurate time according to the timer time.

  Hereinafter, a preheat system showing an embodiment relating to a time switch of the present invention will be described based on the drawings. FIG. 1 is a block diagram showing a schematic configuration of the entire preheat system showing the present embodiment.

  A preheating system 1 shown in FIG. 1 includes a heater 3 that heats the inside of the reflow furnace 2, a temperature sensor unit 4 that detects a room temperature inside the reflow furnace 2, an SSR 5 that turns ON / OFF the power supply to the heater 3, Based on the current indoor temperature detected by the temperature sensor unit 4, it has a temperature regulator 6 that controls the ON / OFF of the SSR 5.

  The time switch 10 is connected to the temperature controller 6, and for example, when the current time reaches a timer setting time such as a preheating start time, the temperature controller 6 is turned on to perform the preheating operation of the heater 3. A drive control signal is output to the device 6.

  FIG. 2 is a block diagram showing a schematic configuration inside the time switch 10 according to the present embodiment.

  2 includes a temperature-compensated reference clock circuit 11 that generates a reference clock, and a time counter that outputs a counter signal in units of one second based on the reference clock generated by the temperature-compensated reference clock circuit 11. A circuit 12, a setting unit 13 for setting a timer setting time, a display unit 14 for displaying various information such as a current time and a timer setting time, a power supply circuit 15 for supplying power to the entire time switch 10, and a preheating system 1, an external input interface 17 for the preheat system 1, and a control circuit 18 for controlling the entire time switch 10.

  When the control circuit 18 detects the counter signal of the time counter circuit 12, it counts the current time by adding 1 second to the current time, and the measured current time reaches the timer set time set by the setting unit 13. When the current time reaches the timer set time, a drive control signal is output to the temperature regulator 6 in the preheat system 1 through the output interface 16.

  The temperature-compensated reference clock circuit 11 has a function of generating a reference clock of, for example, 32768 Hz and compensating for a frequency variation of the reference clock with respect to a change in the current temperature. FIG. 3 is an explanatory diagram showing the relationship between the environmental temperature of the temperature compensated reference clock circuit 11 and the frequency error of the reference clock. The temperature compensated reference clock circuit 11 can be compared with the conventional clock circuit. The characteristics are such that no frequency error occurs with respect to changes in environmental temperature.

  The temperature-compensated reference clock circuit 11 compensates for a temperature sensor unit 11A that detects the current temperature in the time switch 10, a crystal oscillator 11B that generates a reference clock of, for example, 32768 Hz, and a frequency variation corresponding to the environmental temperature. The temperature compensation table 11C storing the compensation values (characteristics shown in FIG. 3) and the compensation value corresponding to the current temperature detected by the temperature sensor unit 11A are read from the temperature compensation table 11C, and the reference is based on the compensation values. A clock controller 11D for compensating for a clock frequency error.

  The time counter circuit 12 receives the reference clock generated by the temperature compensated reference clock circuit 11 and counts the reference clock. When the count number of the reference clock reaches a predetermined count number, the counter signal is sent to the control circuit. 18, a counter counter table 12B that stores a correction value for correcting the predetermined count number, and a predetermined count number of the time counter circuit 12A based on the correction value stored in the counter correction table 12B. And a counter correction unit 12C for correction.

  FIG. 4 is an explanatory diagram briefly showing the operation principle of correcting a predetermined count number every 20 seconds in the time counter circuit 12 according to the present embodiment.

  For example, when counting one second with a reference clock of 32768 Hz, the time counter circuit 12 sets the predetermined count number to 32768, determines whether or not the reference clock count number has reached the predetermined count number, When the count number reaches a predetermined count number, a counter signal indicating one second is output to the control circuit 18.

  Further, since the counter correction unit 12C may have a product variation of the temperature compensation type reference clock circuit 11, the counter correction unit 12C is based on the correction value stored in the counter correction table 12B at a timing of once every 20 seconds as shown in FIG. The predetermined count is corrected and set to 32848 (32768 + 80). Since the correction value is calculated at a timing of once every 20 seconds, the correction resolution is 1 / (32768 * 20 seconds) = 1.52PPM. When an actual measurement value of the oscillation frequency of the reference clock of the actual temperature compensated reference clock circuit 11 is 327688.2 Hz and an oscillation frequency of the basic ideal reference clock is 32768 Hz, a lead error of +6.10 PPM occurs. The advance amount in 20 seconds is 6.10 PPM * 20 seconds = 122 PPM. Since the correction resolution is 1.52 PPM, the correction value is 122 PPM / 1.52 PPM = 80.2631≈80.

  That is, the time counter circuit 12 corrects and sets the predetermined count number to 32848 (32768 + 80) at a timing of once every 20 seconds, and the reference clock count reaches the predetermined count (32848). When judged, the counter signal is outputted to the control circuit 18.

  The current time measuring means is the time counter circuit 12 and the control circuit 18, the timer time setting means is the setting unit 13, the control means is the control circuit 18, and the temperature compensated reference clock generating means is the temperature compensated reference clock circuit. 11. Compensation value storage means: temperature compensation table 11C; temperature detection means: temperature sensor unit 11A; clock generation means: crystal oscillator 11B; temperature compensation means: clock control unit 11D; counter means: time counter unit 12A; The means corresponds to the counter correction table 12B, the count number correction means corresponds to the counter correction unit 12C, and the load device corresponds to the temperature controller 6 of the preheat system 1 or the like.

  Next, operation | movement of the preheat system 1 which shows this Embodiment is demonstrated. FIG. 5 is a flowchart briefly showing the processing operation of the inspection device in the counter correction table update processing according to the present embodiment.

  The counter correction table update process shown in FIG. 5 is an inspection that is externally connected to the time switch 10 at the time of shipment of the time switch 10 in order to absorb a time error due to product variations in the temperature compensated reference clock circuit 11 inside the time switch 10. In this process, the correction value is calculated by the device, and the correction value is stored and updated in the counter correction table 12B.

  The inspection device is externally connected to the time counter circuit 12 and the temperature compensated reference clock circuit 11 in the time switch 10 when the time switch 10 is shipped, and the reference clock from the temperature compensated reference clock circuit 11 in the time switch 10 is connected. The oscillation frequency is measured (step S11).

  The inspection device calculates an advance error between the measured actual oscillation frequency of the reference clock and the ideal oscillation frequency of the reference clock (step S12). It is assumed that the ideal reference clock oscillation frequency is stored in advance in the inspection device.

  After calculating the advance error, the inspection device calculates a correction value by dividing the advance error by the correction resolution in order to absorb the advance error (step S13).

  The inspection device writes and updates the calculated correction value in the counter correction table 12B in the time switch 10 (step S14), and ends this processing operation.

  According to the counter correction table update process shown in FIG. 5, when the time switch 10 is shipped, the inspection device is externally connected to the temperature-compensated reference clock circuit 11 and the time counter circuit 12 in the time switch 10, and the current time switch 10 Measure the oscillation frequency of the reference clock, calculate the advance error between the measured oscillation frequency of the reference clock and the ideal oscillation frequency of the reference clock, and calculate the correction value to correct this calculated advance error. Since the value is stored and updated in the counter correction table 12B in the time switch 10, the time error due to the product variation of the temperature compensated reference clock circuit 11 can be absorbed when the time switch 10 is shipped.

  FIG. 6 is a flowchart showing the processing operation related to the drive control signal output processing of the time switch 10 according to the present embodiment.

  The drive control signal output process shown in FIG. 6 determines whether or not the current time has reached the timer set time, and if it is determined that the current time has reached the timer set time, the temperature regulator 6 of the preheat system 1. Is a process of outputting a drive control signal.

  In FIG. 6, when the clock control unit 11D in the temperature compensation type reference clock circuit 11 detects the current temperature through the temperature detection unit 11A (step S21), the compensation value corresponding to the current temperature is read from the temperature compensation table 11C. Based on the compensation value, the frequency variation of the reference clock oscillated by the crystal oscillator 11B is compensated and the reference clock is output (step S22).

  Each time the control circuit 18 detects the counter signal of the time counter circuit 12, the control circuit 18 performs a time measuring operation for measuring the current time by one second (step S23). The time counter 12A in the time counter circuit 12 counts the reference clock from the temperature-compensated reference clock circuit 11, and outputs a counter signal when the reference clock count reaches a predetermined count. is there. The counter correction unit 12C corrects the predetermined count number in the time counter unit 12A once every 20 seconds based on the correction value stored in the counter correction table 12B. Then, when the count number of the reference clock reaches the same corrected count number, the time counter circuit 12 outputs a counter signal to the control circuit 18, and the counter correction unit 12C is set in the time counter unit 12A. The corrected predetermined count number is set to a predetermined count number before correction.

  The control circuit 18 determines whether or not the current time has reached the timer set time set by the setting unit 13 while executing the time counting operation of the current time (step S24).

  If the current time has reached the timer setting time (preheating start time), the control circuit 18 sends a drive control signal to the temperature controller 6 in the preheating system 1 via the output interface 16 in order to start heater preheating. It outputs to the temperature regulator 6 (step S25), and this processing operation is complete | finished.

  If the current time has not reached the timer set time, the control circuit 18 continues the time counting operation of the current time and proceeds to step S21 to compensate for the frequency variation of the reference clock suitable for the current temperature. To do.

  According to the drive control signal output processing shown in FIG. 6, the frequency variation of the reference clock is compensated based on the compensation value corresponding to the current temperature, and the current time is counted based on the compensated reference clock. When it is determined that the timer set time has been reached, a drive control signal is output to the temperature controller 6 in order to start the heater preheating of the preheat system 1, so that the reference clock used to count the current time By compensating the frequency variation with respect to the current temperature, it is possible to measure the correct current time, and as a result, it is possible to output the drive control signal to the temperature controller 6 at the correct time.

  According to the present embodiment, a temperature-compensated reference clock circuit 11 is used to generate a reference clock that compensates for a frequency variation with respect to the current temperature, and the current time is counted based on the reference clock. When it is determined that the set time has been reached, a drive control signal is output to the temperature controller 6 in order to start the heater preheating of the preheating system 1, and thus the preheating operation of the heater 2 is started at an accurate time. As a result, the work can proceed smoothly without delaying the subsequent work start time.

  In the above embodiment, the preheat system 1 in which the time setting time of the time switch 10 is set as the heater preheating start time has been described as an example, but the present invention may be applied to the chime output system shown in FIG.

  FIG. 7 is a block diagram showing a schematic configuration inside the chime output system showing another embodiment relating to the time switch 10 of the present invention.

  The chime output system 20 shown in FIG. 7 includes an acoustic device 21 that generates a chime sound, an amplifier 22 that amplifies the chime sound generated by the acoustic device 21, a speaker 23 that outputs the amplified chime sound, and a The controller 23 controls the entire chime output system 20, and the controller 23 outputs the chime sound generated by the acoustic device 21 to the speaker. The time switch 10 is connected to the controller 23.

  The time switch 10 sets the time at which the chime sound is acoustically output through the setting unit 13 as the timer setting time, and outputs the drive control signal to the controller 24 through the output interface 16 when the current time reaches the timer setting time.

  When the controller 24 detects the drive control signal from the time switch 10, the controller 24 outputs the chime sound generated by the acoustic device 21 through the amplifier 22 to the speaker.

  As described above, according to the chime output system 20 shown in the other embodiment, the reference clock that compensates the frequency variation with respect to the current temperature is generated on the time switch 10 side using the temperature compensated reference clock circuit 11, Based on this reference clock, the current time is counted, and if it is determined that the current time has reached the timer set time, a drive control signal is output to the controller 24 to output a chime sound to the chime output system 20 through a speaker. As a result, the user can be informed of the correct current time.

  FIG. 8: is a block diagram which shows schematic structure inside the illumination cultivation system which shows other embodiment.

  The lighting cultivation system 30 shown in FIG. 8 has the lighting fixture 31 which gives light to the cultivation plant in a greenhouse, and the lighting controller 32 which controls this lighting cultivation system 30 whole, and the lighting controller 32 is in a greenhouse. The lighting fixture 31 is controlled to be turned on. The time switch 10 is connected to the illumination controller 32.

  The time switch 10 is configured to set a timer setting time such as an illumination turn-on time or an illumination turn-off time through the setting unit 13.

  When the current time reaches the lighting lighting time, the time switch 10 outputs a drive control signal to the lighting controller 32 to turn on the lighting fixture 31. And the lighting controller 32 will light the lighting fixture 31, if the drive control signal from the time switch 10 is detected.

  When the current time reaches the illumination extinction time, the time switch 10 outputs a drive control signal to the illumination controller 32 to extinguish the lighting fixture 31 that is lit. And the lighting controller 32 will light-extinguish the lighting fixture 31, if the drive control signal from the time switch 10 is detected.

  According to the lighting cultivation system 30 which shows other embodiment, the reference clock which compensated the frequency fluctuation part with respect to the present temperature was generated using the temperature compensation type reference clock circuit 11, and the present time is measured based on this reference clock. In addition, when it is determined that the current time has reached the timer setting time, a drive control signal is output to the lighting controller 32 in order to drive and control the luminaire 31. As a result, the lighting fixture 31 can be turned off or turned on at an accurate time.

  In the above embodiment, as an example using the time switch 10, the preheat system 1, the chime output system 20 and the lighting cultivation system 30 have been described as examples. For example, timer management of the injection / cooling cycle time, Timer management of press time, timer management of intermittent operation time such as defrosting of freezer, timer management of operation timing of industrial machinery, timer management to manage filling amount of liquid filling tank in time unit, winding amount in time unit It can be applied to various fields, such as timer management that manages the lighting, timer management that manages the turning off and lighting of road lighting in units of time, and timer management that controls the turning off and lighting of vending machine lights in units of time Needless to say.

  In the above embodiment, the configuration in which the time counter circuit 12 is externally connected to the control circuit 18 as shown in FIG. 2 has been described. However, the time counter circuit 12 can be connected without externally connecting the time counter circuit 12. Needless to say, the control circuit 18 may be provided with a time counter processing unit that executes twelve processing operations, and the same effects as those of the present invention can be obtained.

  The time switch of the present invention has a temperature-compensated reference clock generating means for generating a reference clock and compensating for a frequency variation of the reference clock with respect to a change in the current temperature. Since the current time is measured based on the reference clock, the accurate current time can be measured even if the environmental temperature fluctuates. As a result, when the current time reaches the timer time, Since the drive control signal can be output, it is useful in various technical fields of timer management.

It is a block diagram which shows schematic structure of the whole preheat system which shows embodiment using the time switch of this invention. It is a block diagram which shows schematic structure inside the time switch in connection with this Embodiment. It is explanatory drawing which shows the relationship between the environmental temperature of the temperature compensation type | mold reference clock circuit inside the time switch in connection with this Embodiment, and the frequency error of a reference clock. It is explanatory drawing which shows briefly the operation principle which correct | amends the predetermined count number in the time-counter circuit concerning this Embodiment. It is a flowchart which shows the processing operation regarding the counter correction table update process of the test | inspection apparatus concerning this Embodiment. It is a flowchart which shows the processing operation in connection with the drive control signal output process of the time switch concerning this Embodiment. It is a block diagram which shows schematic structure of the whole chime output system which shows other embodiment. It is a block diagram which shows schematic structure of the whole lighting cultivation system which shows other embodiment. It is a block diagram which shows schematic structure of the whole preheat system using the conventional time switch. It is explanatory drawing which shows directly the relationship between the environmental temperature of the reference clock circuit inside the time switch of a prior art, and the frequency error of a reference clock.

Explanation of symbols

1 Preheat System 10 Time Switch 11 Temperature Compensated Reference Clock Circuit (Temperature Compensated Reference Clock Generation Unit)
11A Temperature sensor (temperature detection means)
11B crystal oscillator (clock generation means)
11C Temperature compensation table (compensation value storage means)
11D clock controller (temperature compensation means)
12 Timekeeping counter circuit (current timekeeping means)
12A clock counter (counter means)
12B Counter correction table (correction value storage means)
12C counter correction unit (count number correction means)
13 Setting part (Timer time setting means)
18 Control circuit (current time measuring means and control means)

Claims (7)

Current time measuring means for measuring the current time based on the reference clock, timer time setting means for setting the timer time, and the current time measured by the current time measuring means is set to the timer time set by the timer time setting means. A time switch having a control means for outputting a drive control signal for driving and controlling the load device when reaching,
A temperature-compensated reference clock generating means for generating the reference clock and compensating for a frequency variation of the reference clock with respect to a change in current temperature;
The current time counting means is:
A time switch for measuring the current time based on the reference clock generated by the temperature compensated reference clock generating means. The temperature-compensated reference clock generating means is
Compensation value storage means for storing a compensation value for compensating frequency fluctuation of the reference clock for each temperature;
Temperature detection means for detecting the current temperature;
Clock generating means for generating the reference clock;
Temperature compensation means for reading a compensation value corresponding to the current temperature detected by the temperature detection means from the compensation value storage means, and based on the compensation value, compensating for frequency fluctuations of the reference clock generated by the clock generation means; The time switch according to claim 1, further comprising: The current time counting means is:
Counter means for counting the reference clock generated by the temperature-compensated reference clock generating means, and outputting a counter signal when the count number of the reference clock reaches a predetermined count number;
Correction value storage means for storing a correction value for correcting the predetermined count number;
The correction value storage means has a count number correction means for correcting a predetermined count number in the counter means based on the correction value stored in the correction value storage means, and measures the current time in a predetermined unit based on the counter signal. The time switch according to claim 1 or 2. The reference clock generated by the temperature-compensated reference clock generation means is compared with an ideal reference clock, a correction value for correcting a time error is calculated based on the comparison result, and the calculated correction value is used as the correction value. 4. The time switch according to claim 3, wherein the storage means updates the storage. The load device corresponds to a preheat system for changing the heater temperature in the reflow furnace,
The control means includes
3. A drive control signal for driving and controlling the preheat system is output when the current time measured by the current time measuring means reaches a timer time set by the timer time setting means. , 3 or 4 time switch. The load device corresponds to a notification sound output system for outputting a notification sound.
The control means includes
2. A drive control signal for driving and controlling the notification sound output system is output when a current time measured by the current time counting means reaches a timer time set by the timer time setting means. , 2, 3 or 4 time switch. The load device corresponds to a lighting system that turns on or off the lighting,
The control means includes
2. A drive control signal for driving and controlling the illumination system is output when a current time measured by the current time measuring means reaches a timer time set by the timer time setting means. , 3 or 4 time switch.

Images