JP2004205465A - Master clock system and master clock used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the distance limitation of a system according to the arrival distance of the radio communication of a radio type master clock system and the limitation of the number of installed slave clocks by simultaneously installing a plurality of master clock systems for management. <P>SOLUTION: The master/slave clock system has a slave clock for correcting time by transmitting time information from a master clock by radio in a relay. The master clock (2) comprises a reception means (21) for receiving standard time information; a correction means (23) for correcting own time, based on the received standard time information; a transmission means (28) for creating time information for correcting the time of the slave clock in the system for transmitting to the slave clock in the system by radio, based on the corrected own clock; and a means (41) for transmitting the time of the master clock to the master clock of another master clock system as standard time information. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention generally relates to a parent-child clock system for correcting the time of a child clock. More specifically, the present invention relates to a master / slave clock system that allows a master clock to transmit standard time information to a master clock of another master / slave clock system by wire in a master / slave clock system that wirelessly corrects time by a relay system, and to the master clock. .
[0002]
[Prior art]
The master clock transmits time information as a reference by radio waves or the like, and the slave clocks placed around it receive this and correct the time based on the reference time information of the master clock to match the time of the master clock. 2. Description of the Related Art A wireless parent-child clock system is known. The reference time of the master clock is generated by receiving it from an external standard time information source by radio waves or the like. Since this wireless parent-child clock system does not require a wire for relay-type transmission of time information, a plurality of child clocks that display a time that matches the time of the parent clock are relatively freely arranged on the premises or premises. It is suitable for
[0003]
For example, even in a wireless parent-child clock system installed in a relatively large site or in a complex building, the master clock can transmit reference time information to the slave clock in a relay manner, and further, the position of the slave clock can be relatively determined. Japanese Unexamined Patent Application Publication No. 2004-131131 discloses a device that can be freely selected or changed.
[0004]
[Patent Document 1]
JP 2002-148371 A
[0005]
[Problems to be solved by the invention]
In the parent-child clock system described in Patent Literature 1, time information is transferred in a relay manner in the system, so that a wireless parent-child clock system can be installed in a relatively large site or in a complex building. The position of the slave clock can be relatively freely selected or changed. However, in the conventional parent-child clock system, the master clock either receives standard time information by radio waves or acquires standard time information by wire. There was a problem that we had to try. Further, in the conventional parent-child clock system, since the time information is transmitted between the sub-clocks in the system in a relay system, there is a problem that the number of sub-clocks is limited due to the accumulated error caused by the relay-type transmission. there were. For this reason, the installation range of the parent-child clock system has been limited to an area limited in distance.
[0006]
[Means for Solving the Problems]
Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art.
In order to achieve this object, the present invention according to claim 1 is a parent-child clock system including a child clock that performs time correction by transmitting time information wirelessly from a master clock in a relay manner. Receiving means capable of receiving standard time information, correcting means for correcting its own time based on the received standard time information, and correcting the time of a slave clock in the system based on the corrected own time Transmission means for generating the time information of the master clock and wirelessly transmitting the time information to the slave clock in the system, and means for transmitting the time of the master clock to the master clock of another master / slave clock system as standard time information. To provide a parent-child clock system.
[0007]
According to the present invention, with the above configuration, the master clock of the master clock system can transmit its own time information to the master clock of another master clock system as standard time information. On the other hand, a master clock of another master clock system can selectively acquire standard time information or time information from another master clock by the receiving means, and can have selectivity in a method of acquiring time information of the master clock. . In addition, another parent-child clock system connected by communication with one parent-child clock system can be provided, and the number of accompanying child clocks can be increased. The communication may be a dedicated parallel communication for a timepiece system, a general-purpose parallel communication such as GP-IB, a dedicated serial communication, a wired communication such as a general-purpose serial communication such as RS232C, RS-422 / 485, or a wireless communication. In this way, it is possible to synchronize the times of the master clocks of a plurality of master / slave clock systems.
[0008]
According to a second aspect of the present invention, in the master-slave clock system according to the first aspect, the receiving unit can acquire standard time information by wireless and wired, and the receiving unit normally receives the standard time information by radio waves. However, in other cases, the present invention provides a parent-child clock system characterized by switching from a master clock of another master clock system to standard time information transmitted via wired communication and receiving the standard time information.
[0009]
In the master-slave clock system of the present invention, the master clock normally receives the standard time information by radio waves such as GPS or JJY, but if the reception of the standard time information by radio waves is difficult for some reason, By receiving the standard time information transmitted from the master clock of the master clock system via wired communication, the master clock of the master-child clock system can reliably acquire the standard time information.
[0010]
According to a third aspect of the present invention, there is provided the parent-child clock system according to the first or second aspect, wherein the means for transmitting by wire communication is the Internet or an intranet.
[0011]
According to the present invention, the master clocks of a plurality of master / slave clock systems can perform wired communication via the Internet or an intranet. Therefore, the master clock and the master-slave clock system can be managed and monitored via the Internet or an intranet. The master clock may include, for example, a wired communication unit using Ethernet (registered trademark).
[0012]
According to a fourth aspect of the present invention, in the parent-child clock system according to the third aspect, the parent clock has an IP address of the parent clock itself and a local IP address of the child clock in the parent-child clock system. A parent-child clock system is provided that is accessible via a parent clock.
[0013]
With the above configuration, the present invention can access the master clock and the slave clock of the master-slave clock system via the Internet or an intranet.
[0014]
According to a fifth aspect of the present invention, in the parent-child clock system according to any one of the first to fourth aspects, the sub-clock includes a receiving unit that wirelessly receives the time information, and a self-timer based on the received time information. Time information for correcting the time of another slave clock based on the corrected own time, and rank information for distinguishing from the time information received by the receiving means. Transmitting means for relaying the information to a lower-rank slave clock in the system in a relay manner, the master-slave clock system being provided.
[0015]
According to the present invention, with the above configuration, time information can be wirelessly transmitted to a slave timepiece in a master / slave timepiece system in a relay manner.
[0016]
According to a sixth aspect of the present invention, in the parent-child clock system according to the fifth aspect, the slave clock transmits individual identification information to transmit the individual identification information for identifying itself to the transmitted time information. The present invention further provides a parent-child clock system, further comprising individual identification information control means provided to the means for performing the operation.
[0017]
According to the present invention, with the above configuration, each sub-watch transmits individual identification information for identifying itself attached to the time information and transmits the same. Source can be confirmed.
[0018]
According to a seventh aspect of the present invention, there is provided a master clock for a master-slave clock system for performing time correction by transmitting time information from a master clock to a slave clock in a relay manner, wherein the master clock can receive standard time information. Receiving means, correcting means for correcting its own time based on the received standard time information, and time information for correcting the time of a slave clock in the system based on the corrected own time. Transmitting means for wirelessly transmitting the clock to the slave clock in the system, and means for transmitting the time of the master clock to the master clock of another master clock system as standard time information. I do.
[0019]
According to the present invention, with the above configuration, the master clock of the master-slave clock system can transmit its own time information to the master clock of another master clock system as standard time information. On the other hand, the master clock of another master clock system can selectively acquire the standard time information by radio wave or the time information from another master clock by the receiving means, and provide the selectivity of the method of acquiring the standard time information of the master clock. be able to. In addition, another parent-child clock system connected by communication with one parent-child clock system can be provided, and the number of accompanying child clocks can be increased.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 schematically shows three parent-child clock systems 11, 12, and 13 according to one embodiment of the present invention. The parent-child clock system 11 includes a master clock 2, a first-rank child clock 3A1, and two second-rank child clocks 3B1 and 3B2. The parent-child clock system 12 similarly has a parent clock 2 ', a first-rank child clock 3A1', and two second-rank child clocks 3B1 'and 3B2'. The parent-child clock system 13 similarly has a parent clock 2 ″, a first-rank child clock 3A1 ″, and two second-rank child clocks 3B1 ″ and 3B2 ″. However, each of the parent and child clock systems 11, 12, 13 can have more ranks and more child clocks without being limited to the above-described rank and child clock arrangement. Further, a slave clock connected to the system via a relay (not shown) may be provided. Since the master clock and the slave clocks constituting the master-slave clock systems 11, 12, and 13 are the same, only the master clock 2 and the slave clocks 3A1, 3B1, and 3B2 of the master-slave clock system 11 will be described below.
[0021]
In each of the parent-child clock systems 11, 12, and 13, a predetermined output is provided between the parent clock 2 and the first-rank child clock 3A1, and between the first-rank child clock 3A1 and the second-rank child clocks 3B1 and 3B2. And are communicably connected by radio waves having a predetermined frequency. Therefore, information including time information is bidirectionally relayed to each of the systems 11, 12, and 13. Radio power and frequency are chosen to be large enough to require no licensing or permission by law. The radio waves may be at the same frequency.
[0022]
The master clocks 2, 2 ′, 2 ″ of each of the master-slave clock systems 11, 12, and 13 are interconnected so as to be capable of two-way communication by the master-clock communication means 7 by wire communication. Dedicated parallel communication for a clock system, general-purpose parallel communication such as GP-IB, dedicated serial communication, general-purpose serial communication such as RS232C, RS-422 / 485, etc., or Ethernet for constructing an intranet. The communication unit 7 can transmit and receive time information for synchronizing the time of the master clocks 2 of the plurality of master and child clock systems 11, 12, and 13.
[0023]
Master clock 2 has the configuration shown in the block diagram of FIG. In other words, master clock 2 receives an external standard time information radio wave (broadcast time signal, long-wave standard radio wave, global positioning system (GPS) time information, etc.) via antenna 20 and receiver 21, and decoder 22 Use the time code of the standard time information. However, the present invention is not limited thereto, and the master watch 2 may receive external standard time information via a wire of the telephone JJY. The time when the master clock 2 receives the standard time information from the outside can be controlled in a predetermined time zone by the identification number control unit 27 that controls the power supply control unit 29 that supplies power to the receiver 21. The time code of the received standard time information is sent to the time correction means 23 via the decoder 22. Then, based on the time code of the standard time information, the time correction unit 23 generates correction information for correcting the time to match the standard time, and sends the correction information to the clock unit 24. The clock unit 24 corrects its own time to match the standard time and corrects the time display of the time display unit 25. The timer 24 sends reference time information to the encoder 26 for transmission to the slave clock to correct the time of the slave clock. The encoder 26 receives data for identifying the information from the master clock 2 from the identification number control means 27, attaches the data to the reference time information, and sends it to the transmitter 28.
[0024]
When a predetermined time during which the master clock 2 transmits the reference time information is reached, power is supplied to the transmitter 28 from the power supply control unit 29 by the identification number control unit 27. Then, the transmitter 28 attaches the error information Δ1 and the information for identifying the information from the master clock to the reference time information via the antenna 20, and transmits the slave clock in the master-slave clock system 1 at a predetermined frequency and output carrier radio wave. Send to watch.
[0025]
The radio wave transmitted by the master watch 2 and the radio wave described later transmitted by each slave clock may have the same frequency. However, as described later, the transmission is performed by shifting the time so that the transmission times of the master clock 2 and the slave clock do not coincide with each other to avoid interference. Instead, radio waves transmitted by the master watch 2 and radio waves transmitted by the slave watches may be set to different frequencies to avoid interference.
[0026]
In addition, the master clock 2 encodes the reference time information for intranet by the Internet protocol encoder 44, and adds the IP address of the master clock 2 from the IP address control unit 46 by the Internet protocol control unit 43. , Via the Ethernet control means 42 and the Ethernet input / output means 41. Further, the master clock 2 receives reference time information transmitted from the master clock of another master / slave clock system via the Ethernet of the master clock communication means 7 by the Ethernet input / output means 41 and the Ethernet control means 42, and The time code is converted by the control means 43 and the Internet protocol decoder 45. Then, based on the reference time information from another master clock received by the master clock communication means 7, the time correction means 23 determines the time of the own clock means 24 and the time of the slave clock in the own system as described above. Reference time information can be generated.
[0027]
Each of the parent clocks 2, 2 ', 2 "of the parent and child clock systems 11, 12, 13 receives, for example, standard time information from the outside at the same time or different times, and if the standard time information is successfully received. For example, the master timepiece transmits its own reference time information to the master timepiece communication means 7 as described above, and the master timepiece which has failed to receive the external standard time information receives another timepiece received through the master timepiece communication means 7. The reference time information from the master clock is used to correct the time of itself and the slave clock in the own system, and the master clock that has successfully received the external standard time information is transmitted via the master clock communication means 7. The reference time information from another master clock received by the master clock may be used to synchronize with the own clock means or to know the accuracy of the own clock means. Reference time information When used to correct the time of the slave clock in the system, the IP address of the other master clock, etc., and the accuracy of its own clock when compared with the reference time information from the other master clock, etc. Can be displayed.
[0028]
The clocking unit 24 controls the power supply control unit 29 in cooperation with the identification number control unit 27 for identifying the master clock 2 as described above, and transmits the predetermined reference time information transmission time or the radio wave from the slave clock. Only during the reception time, the power is sent to the transmitter 28, the receiver 21, and other necessary circuits to save power consumption.
The master clock 2 can receive, via the antenna 20, the receiver 21, and the decoder 22, information on time information received by each slave clock for time correction from each slave clock in the system 1 during uplink. it can. The information from each of the slave clocks is displayed by the display means 22A as necessary, and can be used by the administrator of the master and slave clock system for management and maintenance of the system. Further, the system may be configured so that an administrator can use the system for management and maintenance of the system via the inter-master-clock communication unit 7.
[0029]
FIG. 3 shows, as the child clock 3, the configuration of the first-rank child clock 3A1 and the second-rank child clocks 3B1 and 3B2 of each of the parent-child clock systems 11, 12, and 13. Each slave clock has the same configuration, and can bidirectionally communicate with the master clock 2 and other slave clocks in each system by the antenna 30, the receiver 31, and the transmitter.
[0030]
The configuration of the slave timepiece 3 in FIG. 3 will be described by taking the first rank timepiece 3A1 as an example. The slave timepiece 3 wirelessly receives the reference time information from the master timepiece 2 by the antenna 30 and the receiver 31, converts the reference time information into a time code by the decoder 32, and sends the time code to the time correction means 33. Further, the decoder 32 detects that the reference time information has been transmitted from the master clock 2 and sends it to the rank control means 37A. If the reference time information has been successfully received, the rank control means 37A stops the power supply from the power supply control means 39 to the receiver 31 and other circuits, and waits for a predetermined time until the next reference time information is received. , Stop receiving.
[0031]
If the decoder 32 cannot restore the time information sent from the master clock 2 (or another slave clock) to the time code, the time adjustment by the time adjustment means 33 is stopped. Then, it instructs not to send the time information to another slave clock. Further, the decoder 32 notifies the rank control unit 37A that the acquisition of the time information has failed, and the master clock 2 receives the time information wirelessly via the encoder 36, the transmitter 38, and the antenna 30 during the uplink. Notify failure.
[0032]
The time adjustment means 33 creates adjustment information for adjusting its own time based on the reference time information received from the master clock 2, and adjusts the time of the clock means 34 to match the time of the master clock 2. Then, the timer 34 corrects the time display on the time display 35. Then, based on the time of the clocking means 34, first-rank reference time information for correcting the time of the second-rank slave clock 3B1 is created and sent to the encoder 36. The reference time information of the first rank is transmitted at a predetermined transmission time of the slave clock 3A1 of the first rank described later. The reference time information of the first rank is time information of the clock means 34 corresponding to a predetermined transmission time of the slave clock 3A1 of the first rank, and is different from the reference time information from the master clock 2 and is longer than the reference time information. This is the time information after the target.
[0033]
The encoder 36 further adds data for distinguishing from the reference time information of the master clock to the reference time information of the first rank. Based on the information from the decoder 32, the rank control unit 37A sends the encoder 36 data indicating that the time information to be transmitted is the first rank reference time information. Further, the individual identification number control means 37 gives the encoder 36 data for identifying the slave clock 3A from other slave clocks in the parent-slave clock system 1. The encode 36 includes, in the first rank reference time information from the timekeeping means 34, data indicating that it is the first rank reference time information from the rank control means 37 A, and a specific child from the individual identification number control means 37. The data indicating the clock 3A is added and sent to the transmitter 38.
[0034]
The transmitter 38 transmits information to another slave clock via the antenna 30 at a predetermined transmission time. The predetermined transmission time is determined as described later, and does not overlap with the transmission time of the master clock 2 or another slave clock using the same transmission frequency, thereby avoiding interference. The transmission time of each slave clock is the rank of the slave clock, that is, the first-rank slave clock 3A that directly receives the reference time information from the master clock 2, and the reference time of the first rank from the first-rank slave clock. The time is sequentially shifted so as to be delayed according to the second-rank slave clock 3B receiving the information and the third-rank slave clock 3C receiving the second-rank reference time information from the second-rank slave clock. ing. Further, there are a plurality of sub-watches (for example, sub-watches 3A1 and 3A2 in the first rank, sub-watches 3B1 and 3B2 in the second rank, and sub-watches 3C1, 3C2, 3C3 in the third rank) even in the same rank. For this purpose, each slave clock is further subdivided according to the individual identification number of the slave clock and transmitted at the assigned transmission time.
[0035]
The power supply control means 39 obtains the above-mentioned own rank from the rank control means 37A, obtains its own individual identification number from the individual identification number control control means 37, and is assigned based on its own rank and individual identification number. The timer means 34 knows that the predetermined time has been reached, and supplies power to the transmitter 38 to perform transmission.
[0036]
The power supply control means 39 starts supplying power to the receiver 31 during the transmission time of the time information from the master clock 2 and the slave clock higher in rank than its own, receives the time information, and receives the time information. The supply of power to 31 is stopped. Here, the first slave clock 3A1 has the highest rank, so that the receiver 31 is operated during the transmission time of the master clock 2. As a result, power consumption for reception can be saved. In addition to this, the reception of the first or second rank reference time information transmitted by another slave clock is prevented, and the repeated time correction and transmission of the reference time information again are prevented.
[0037]
As described above, the slave watch 3 transmits information such as whether or not the time information was successfully received and the received error information to the master watch 2 at a predetermined uplink time. As described later, the predetermined uplink time is a time zone different from the transmission time of the time information, and different times are assigned to each rank and each individual identification number. When the power control means 38 knows that the predetermined time has come from the time keeping means 34, the individual identification number control means 37, and the rank control means 37A, the power supply control means 38 receives the information of its own individual identification number and the reception of the time information. Power is supplied to the transmitter 38 in order to perform uplink transmission of information including permission / prohibition to the master clock 2.
[0038]
Further, the slave clock 3A1 transmits a lower-rank slave clock, for example, a second-rank slave clock 3B, to the master clock 2 by uplink information of its own individual identification number and whether or not time information can be received. When doing so, relay the radio wave. For this reason, the sub-watch 3A supplies power to the receiver 31 during a time period when the lower-rank sub-watch transmits reception information to the master watch, and receives radio waves from the lower-rank sub-watch.
[0039]
The second-rank child timepieces 3B1 and 3B2 have the same configuration as the first child timepiece 3A1, and perform similar operations. The second-rank slave clock 3B analyzes the fact that the first-rank reference time information from the first-rank slave clock 3A has been received by the decoder 32 and notifies the rank control means 37A. Rank control means 37A identifies itself as a second-rank slave timepiece, sends data indicating that the time information transmitted by itself to the second-rank reference time information to encoder 36, In order to perform reception and transmission at the reception time and transmission time allocated to the slave clocks of the rank, the time of power supply to the receiver 31 and the transmitter 38 is specified via the power supply control means 39. After receiving the reference time information of the first rank, the receiver 31 stops receiving for a certain period of time until the next reception time of the reference time information of the first rank, and receives the time information transmitted by the slave clocks of other ranks. To prevent
[0040]
In the above description of the operation, the second-rank slave clock 3B has been described as being in a state where it cannot receive the reference time information transmitted by the master clock 2, but if it can receive the reference time information from the master clock 2, In this case, it operates in the same manner as the first-rank slave watch 3A, and the time information transmitted by itself can be used as the first-rank reference time information. In this way, the slave clock is generally set in a receivable state when the time information of the higher rank is transmitted, and detects whether the time information of the higher rank can be received. If the information can be received, the reception may be switched to that rank.
[0041]
The time correction means 33 corrects the time of its own clock means 34 based on the reference time information of the first rank, and corrects the time display of the time display means 35. Then, if there is a next third-rank slave clock, the slave clock sends the second-rank reference time information to the encoder 36 for use in time correction. The encoder 36 adds, to the time information, a specific individual identification number of the slave timepiece 3B from the individual identification number control means 37 and information indicating that the reference time information is the second rank, and sends the information to the transmitter 38. . The reference time information of the second rank transmitted by the slave clock 3B of the second rank is time information in the transmission time assigned by the second rank and the individual identification number as described later.
[0042]
FIG. 1 shows each of the parent and child clock systems 11, 12, and 13 from the first-rank child clock 3A1 to the second-rank child clock 3B1 and 3B2. It can be connected in a way that allows two-way communication by radio waves.
[0043]
Each slave clock 3 has its own individual identification number in the individual identification number control means 37, but otherwise has the same configuration. When the basic time information from the master clock 2 is received by the rank control means 37A, the first rank is set. When the reference time information of the first rank is received from the child clock 3A of the first rank, the child clock 3A of the second rank is automatically ranked as the child clock 3B of the second rank. As a result, the sub-watches are interchangeable.
[0044]
Next, time allocation for downlink transmission of time information for time correction from the master clock to the slave clock will be described with reference to FIG. In each of the parent and child clock systems 11, 12, and 13, the frequency of the radio wave used may be changed. When the parent and child clock systems 11, 12, and 13 are separated from each other and do not interfere with each other, the same frequency is used. May be. The downlink transmission is performed, for example, once a day, using one hour at 2:00 am. The time required for each slave clock to receive and transmit the time information is the time allocated to the time. In the example, it is performed in one second. Once the slave clock receives the time information, it is possible to prevent unnecessary power consumption by turning off the power of the receiver as described above. Since subsequent reception of time information is not performed by stopping reception by the receiver, repeated time correction and transmission can be prevented. Each slave clock has higher priority among time information such as receivable reference time information, reference time information of the first rank, reference time information of the second rank, and the like, that is, priority is given to time information closer to the master clock. And configured to receive.
[0045]
The downlink transmission is not limited to once a day. If the downlink transmission is performed once every two to three hours, the accumulated error of the clock in the system can be further suppressed. In addition, some low-accuracy watches have a daily error of about one second due to the effects of quality, temperature changes in the installation environment, and the like. It is difficult to adopt it in the slave clock because it may deviate from the method of completing communication in one second of the example system. For this reason, if the system performs the downlink transmission once every two to three hours, the accumulated error of the clock in the system can be suppressed, and even a low-precision clock can be used as the slave clock. The system can be constructed at low cost.
[0046]
As shown in FIG. 4, downlink transmission of the time information of the first-rank slave clock 3A whose rank is 1 for one minute from 2:00 am to 2:00 am, that is, reference time information of the first rank. It is a time zone. The one-minute time zone is further subdivided into 60 time zones at one-second intervals, and is assigned in accordance with the individual identification number of the first slave watch 3A (a specific number between 1 and 60). Downlink transmission is performed for one second in the time slot. One minute from 2:01 to 2:02 is the time information of the second-rank slave clock 3B of rank 2, that is, the reference time information of the second rank, that is, the downlink transmission time zone. The one-minute time zone is further subdivided into 60 time zones at one-second intervals, and is assigned in accordance with the individual identification number (specified number between 1 and 60) of the second-rank child watch 3B. Downlink transmission is performed for one second in the assigned time zone. The same applies to the case where there are slave watches of the following ranks. In this way, no interference occurs even when radio waves of the same frequency are used.
[0047]
Next, with reference to FIG. 5, a description will be given of an uplink time allocation for transmitting information indicating the reception status of each slave clock from the first to fifth rank slave watches to the master clock 2 by radio waves. In each of the parent and child clock systems 11, 12, and 13, the frequency of the radio wave used may be changed. When the parent and child clock systems 11, 12, and 13 are separated from each other and do not interfere with each other, the same frequency is used. May be. The information from each slave clock includes the individual identification number of the slave clock, whether or not time information for time correction can be received, and the rank of the received time information (ie, reference time information, reference time information of the first and second ranks). Etc.), and the individual identification number of the transmission source of the received time information. The uplink is performed, for example, once a day, using one hour at around 3:00 am. However, the time required for each slave clock to transmit information is an allotted time, one second in this example. Therefore, useless power consumption can be prevented. A reception operation for relay is started in each slave clock when the uplink starts.
As described above, the uplink collects the accumulated error information relating to the time information received by each slave clock in the master clock, monitors the operation status of the entire system, uses it for maintenance work, and, if necessary, It is also possible to replace or change the position of the sub-clock or change the position.
[0048]
As shown in FIG. 5, uplink transmission is started from the lower slave clock in the opposite manner to the downlink. In other words, one minute from 3:00 to 3:00 is the transmission time zone of the information of the child clock of rank 60. The one-minute time zone is further subdivided into 60 time zones at one-second intervals, and one second of the time zone assigned to each individual identification number of the slave clock (a specific number between 1 and 60). Wirelessly. The radio wave transmitted by the slave clock is sequentially relayed by the upper slave clock and transmitted to the master clock 2.
[0049]
One minute from 3:57 to 3:58 is the transmission time zone for the information of the slave clock (not shown) of rank 3. The one-minute time zone is further subdivided into 60 time zones at one-second intervals as described above, and the third-rank slave clock (not shown) is assigned a time zone assigned in accordance with its own individual identification number. Is transmitted in one second. This information is received by the slave clocks 3B1 or 3B2 of rank 2 and added to the information of the slave clocks 3B1 and 3B2 when the slave clocks 3B1 and 3B2 are uplinked, and relayed.
[0050]
One minute from 3:58 to 3:59 is the transmission time zone of the information of the second-rank slave watches 3B1 and 3B2 of rank 2. The one-minute time zone is further subdivided into 60 time zones at one-second intervals as described above, and the sub-clocks 3B and 3B2 have their own individual identification numbers (specific numbers between 1 and 60). The transmission is performed during one second in the time zone correspondingly assigned. The information of the second-rank slave clocks 3B1 and 3B2 is received by the first-rank slave clock 3A1, added to the information of the slave clock 3A1, relayed, and delivered to the master clock 2.
[0051]
The first sub-watch 3A1, which is the first rank, sends information directly to the master watch 2 during one second assigned corresponding to the individual identification number within one minute from 3:59 to 4:00. Send In this way, no interference occurs even when radio waves of the same frequency are used.
[0052]
In the master clock 2, information from all slave clocks is received at 4:00, and the received information is displayed on the display unit 22A. From the displayed state, it is possible to confirm whether each slave clock has actually received the time information and correct the time, and to check the information of the time information received by the slave clock, and replace the slave clock if necessary.・ The reliability of the parent-child clock system can be improved by repairing.
[0053]
FIG. 6 shows another embodiment of the present invention. The difference from the embodiment of FIG. 1 is that the Ethernet of the master-to-master clock communication means 7 is connected to the intranet 8 and further to the Internet via a router (not shown). , And 13 have respective IP addresses, for example, [192.168.200.1], [192.168.200.2], [192.168.200.3], and the like. And can be accessed via the Internet or an intranet.
[0054]
Further, the master clocks 2, 2 ′, 2 ″ are allocated in correspondence with the slave clocks based on the identification numbers of the slave clocks 3 A 1, 3 B 1, 3 B 2, etc. in the own systems 11, 12, 13. The local IP address, for example, [xxx], [yyy], [zzz], etc., is provided in the IP address control means 36 of Fig. 2. As a result, the master clock and the master clock of the master-slave clock system are transmitted. Each child clock can be accessed by the Internet or the intranet 8. Therefore, the administrator can manage and check the parent and child clock systems 11, 12, and 13 via the Internet or the intranet 8. As a result, The efficiency of management and inspection of the parent-child clock system can be improved.
[0055]
In the above-described embodiment, the communication between the master clocks 7 is described as wired communication. However, wireless communication may be used. Alternatively, radio waves of the same frequency may be used during the transmission time zone of rank 1.
[0056]
【The invention's effect】
According to the parent-child clock system of the present invention, a plurality of parent-child clock systems can be installed and operated at the same time, and thus the number of child clocks installed in the wireless parent-child clock system is not limited. Further, there is no limit on the distance of the wireless parent / child clock system, which is based on the reach of wireless communication. Further, since the master clock can be connected to the general-purpose Internet or intranet, the communication infrastructure such as Ethernet can be used as it is, and the installation cost of the master-slave clock system can be greatly reduced. Further, since the master clock can be formed by Ethernet, realizing means for system monitoring and inspection, command control, data acquisition, and the like can be realized by a normal personal computer, which is excellent in convenience and economy. The parent-child clock system can be connected to the Internet by connecting the intranet to the Internet through a router. Further, the master clock connected to the Internet sets not only the information of the master clock itself but also a local IP address based on the identification number of the slave clock connected to the local network in the master-slave clock system, All child clocks are indirectly assigned an IP address so that they can be connected to the Internet and used for management and inspection of child clocks.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a parent-child clock system according to one embodiment of the present invention.
FIG. 2 is a block diagram of a master clock of the master-child clock system according to the embodiment of the present invention.
FIG. 3 is a block diagram of a child clock of the parent-child clock system according to the embodiment of the present invention.
FIG. 4 is a time chart showing time allocation for downlink transmission of time information for time correction of the parent-child clock system according to the embodiment of the present invention.
FIG. 5 is a time chart showing time allocation at the time of uplink of information of a child clock of the parent-child clock system according to the embodiment of the present invention.
FIG. 6 is a schematic diagram of a parent-child clock system according to another embodiment of the present invention.
[Explanation of symbols]
11, 12, 13 Parent-child clock system
2, 2 ', 2 "master clock
3A1, 3B1, 3B2 child clock
7 Communication method between master clocks
8 Internet or intranet
20, 30 antenna
21, 31 receiver
23, 33 time correction means
24, 34 clocking means
26, 36 Encoder
37 Individual identification number control means
37A rank control means
28, 38 transmitter
41 Ethernet input / output means
42 Ethernet control means
43 Internet Protocol Control Means
44 Internet Protocol Encoder
45 Internet Protocol Decoder
46 IP address control means

Claims (7)

A master-slave clock system including a slave clock that transmits time information wirelessly from the master clock and performs time correction,
The master clock is a receiving unit that can receive standard time information, a correcting unit that corrects its own time based on the received standard time information, and the unit in the system based on the corrected own time. Transmitting means for creating time information for correcting the time of the slave clock and wirelessly transmitting the time information to the slave clock in the system, and a master clock of another master-slave clock system using the time of the master clock as standard time information Means for transmitting to a parent-child clock system. 2. The master / slave clock system according to claim 1, wherein the receiving unit can acquire standard time information by radio and wire, and the receiving unit normally receives the standard time information by radio waves, but otherwise receives the other standard time information. A parent-child clock system, wherein the clock is switched to standard time information transmitted from a master clock of the clock system via wired communication and received. 3. The master-slave clock system according to claim 1, wherein the means for transmitting by wire communication is the Internet or an intranet. 4. The master / slave clock system according to claim 3, wherein the master clock has its own IP address and a local IP address of the slave clock in the master / slave clock system, and the slave clock is accessed via the master clock. A parent-child clock system characterized by what is possible. 5. The master / slave clock system according to claim 1, wherein the slave clock receives time information wirelessly, and corrects its own time based on the received time information. 6. Creating time information for correcting the time of another slave clock based on the corrected own time and attaching rank information to the time information to distinguish it from the time information received by the receiving means, A transmission means for transmitting to a lower-rank slave clock in the system in a relay manner. 6. The parent-child clock system according to claim 5, wherein the child clock gives the individual identification information to the transmitting means to transmit the individual identification information identifying itself to the transmitted time information. A parent-child clock system further comprising control means. A master clock for a master-slave clock system that performs time correction by transmitting time information to the slave clock from the master clock in a relay manner,
The master clock is a receiving unit that can receive standard time information, a correcting unit that corrects its own time based on the received standard time information, and the unit in the system based on the corrected own time. Transmitting means for creating time information for correcting the time of the slave clock and wirelessly transmitting the time information to the slave clock in the system, and a master clock of another master-slave clock system using the time of the master clock as standard time information Means for transmitting to the master clock.

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