Data processing: generic control systems or specific application – Generic control system – apparatus or process – Sequential or selective
Reexamination Certificate
2000-12-15
2003-12-02
Patel, Ramesh (Department: 2121)
Data processing: generic control systems or specific application
Generic control system, apparatus or process
Sequential or selective
C700S009000, C700S015000, C700S016000, C700S018000, C700S023000, C700S086000, C713S400000, C713S500000, C713S502000, C713S600000, C713S601000
Reexamination Certificate
active
06658303
ABSTRACT:
BACKGROUND OF INVENTION
1. Field of Invention
This invention relates to a program timer unit used with a remote supervisory control system wherein a transmission signal is transmitted to a signal line according to a time-division multiplex transmission system and load control responsive to supervisory input can be performed using the transmission signal, and more particularly to a program timer unit in a remote supervisory control system for controlling loads in accordance with control programs in which weekly and yearly load control setup times, time schedule, control contents, etc., are set.
2. Related Art
A program timer generally for storing a time schedule and controlling load when the current time counted by an internal clock section matches the time set as the time schedule is provided (JP-A-2-144604). This kind of program timer is adapted to turn on/off an output contact in accordance with a time schedule and can control as many loads as the number of circuits responsive to the number of output contacts.
JP-A-2-144604 discloses an art of using a program timer in a remote supervisory control system for connecting terminals by a two-wire signal line by adopting a time-division multiplexing control system (the remote supervisory control system will be discussed in [Mode for Carrying out the Invention]), and output contracts for eight circuits provided in the program timer are used as supervisory input of each terminal. Therefore, the output contacts of the program timer are handled equivalently to switches and it is made possible to control loads in accordance with the time schedule of the program timer.
That is, as shown in
FIG. 25
, a program timer
1
as supervisory input is connected to a terminal
32
connected to a signal line Ls in a remote supervisory control system. In the figure, power supply of the terminal
32
is provided by stepping down the voltage of commercial power supply AC with a transformer
34
.
By the way, as described above, to control loads in accordance with the time schedule of the program timer
1
in the remote supervisory control system, a separate terminal
32
for receiving as many supervisory inputs as the number of circuits of output contacts is required and moreover as many lines as the number of circuits need to be connected between the program timer
1
and the terminal
32
and thus construction work is cumbersome. Since the number of circuits of loads that can be controlled by the program timer
1
is limited by the number of circuits of output contacts, the number of circuits of loads to be controlled cannot be increased; in contrast, if the number of circuits of loads to be controlled is less than the number of circuits of output contacts, the output contacts become fruitless.
The program timer described in JP-A-2-144604 gives only supervisor input to the remote supervisory control system and cannot receive an instruction from the remote supervisory control system and thus an instruction cannot be given to the program timer
1
unless an operation section of the program timer
1
is operated. For example, if a holiday time schedule is to be selected, the program timer
1
must be operated and cannot be given an instruction for selecting the holiday time schedule from the remote supervisory control system. Further, to temporarily stop control of the program timer
1
or use control of the program timer
1
for any other control than the time schedule, the program timer
1
must also be operated. Moreover, the program timer
1
often is installed in a console and thus the operator cannot operate the program timer
1
unless he or she goes to the console installation location and opens the console; operating the program timer
1
consumes labor and time.
SUMMARY OF INVENTION
It is therefore the main object of the invention to provide a program timer not requiring any additional terminal for connecting to a remote supervisory control system and enabling the number of circuits of loads to be set to any desired number and it is another object of the invention to provide a program timer for enabling various instructions to be given with transmission signals in conjunction with a remote supervisory control system.
Another object of the invention to provide a program timer unit in a remote supervisory control system for making it possible to reduce costs and the installation space.
According to the first aspect of the present invention, there is provided a program timer used with a remote supervisory control system wherein a plurality of terminals comprising unique addresses are connected to a signal line and a transmission signal is transferred according to a time-division multiplex transmission system between a transmission unit connected to the signal line and the terminals and load connected to another terminal can be controlled in response to supervisory input to one of the terminals using the address correspondence, the program timer comprising a program storage section for storing a set of the address related to the load to be controlled and the control contents and the control time of the load as a time schedule, a setting and operation section for setting the control contents and the control time by address and setting a time schedule in the program storage section, a clock section for counting the current time, and a signal processing section, when the control time in each time schedule stored in the program storage section matches the current time counted by the clock section, for functioning as a terminal with the control contents in the time schedule as supervisory input with the address in the time schedule as the address. Since the program timer comprises the signal processing section that can be connected to the signal line connected to the transmission unit, it can be connected directly to the signal line and can control a plurality of loads only with a set of terminals to connect to the signal line regardless of the number of the loads to be controlled (in the embodiment, the signal line is a two-wire line and thus a pair of terminals is only needed). In addition, an additional terminal formerly required becomes unnecessary and consequently, the construction work is facilitated and the flexibility of load control is enhanced.
According to a second aspect of the present invention, in the first aspect of the present invention, time schedules corresponding to a plurality of days are stored in the program storage section on a daily basis, a basic time schedule repeatedly used and a special-day time schedule other than the basic time schedule can be set as the time schedules, and the program timer further includes a special-day specification terminal to which external contact input of no voltage can be connected for specifying which of the basic time schedule and the special-day time schedule is to be used. An appropriate external contact input is connected to the special-day specification terminal, whereby use of the special-day time schedule can be specified from a different location from the installation location of the program timer.
According to the third aspect of the present invention, in the first aspect of the present invention, time schedules corresponding to a plurality of days are stored in the program storage section on a daily basis, a basic time schedule repeatedly used and a special-day time schedule other than the basic time schedule can be set as the time schedules, and the signal processing section comprises a schedule mode flag for specifying which of the basic time schedule and the special-day time schedule is to be used, wherein when the address of a transmission signal transmitted via the signal line matches the address related to the schedule mode flag, the signal processing section switches the schedule mode flag in response to the control contents of the transmission signal. Use of the special-day time schedule can be specified from a different location from the installation location of the program timer by relating to the terminal connected to the signal line.
According to a fourth aspect
Hatemata Takeshi
Yoshimura Yuichi
Matsushita Electric & Works Ltd.
Patel Ramesh
LandOfFree
Program timer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Program timer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Program timer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3176302