JPH053941Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention is applied, for example, to recording the temperature inside a refrigeration system for marine containers, and uses battery power to record changes in process quantities on recording paper using a recording pen. The present invention relates to a self-balancing recorder using a DC servo motor for recording, and particularly to a self-balancing recorder equipped with a mechanism for minimizing battery power consumption during power outages.

[Prior art] Conventionally, 2
A self-balancing temperature recorder with power supplies (external power supply and built-in battery power supply) is constructed as shown in FIG. That is, it converts the resistance value change of the temperature detection terminal TH into a voltage, and also converts the resistance value of the potentiometer 9 fixed to the shaft of the gear 7 into a voltage, and supplies the difference between the two voltages to the amplifier 1. . The output of this amplifier 1 is supplied to a servo motor 2, and the rotation of the servo motor 2 is controlled in accordance with the output of the amplifier 1. When the servo motor 2 rotates, the connecting gears 3, 4, 5, 6, and 7 rotate, the potentiometer 9 fixed to the shaft of the gear 7 rotates, and the input to the amplifier 1 becomes zero, that is, the output becomes zero. Rotate until. A recording pen 11 fixed to the shaft of a fan-shaped gear 8 connected to the gear 7 similarly moves, and a trajectory is recorded on the recording paper 13 by the pen tip 12. Therefore, the scale at the position of the locus recorded by the recording pen 11 on the recording paper 13 always indicates the measured temperature.

Now, if the external power is cut off due to a power outage or the like, the recording function will be continued by the built-in battery 15. The battery 15 is constantly charged by a charger 16. If a power outage continues for a long time and temperature recording is required during that time, a large-capacity battery is required to provide continuous power supply. The refrigeration system for refrigerated containers according to this example is limited in volume and weight in order to load as much cargo as possible into the container, and therefore the capacity of the battery for recording is also limited, so it is practical with a battery of as small a capacity as possible. Period with no problems (usually
Continuous temperature recording is required for 15 days).

[Problems to be solved by the invention] The present invention has been made to solve the above-mentioned problems, and its purpose is to supply power to the servo motor intermittently at a certain period so as to solve the problem during a power outage. Reduces battery power consumption, small capacity (compact/
It is lightweight) and has a battery that allows you to continue recording for a long time.

[Means for Solving the Problems] The self-balancing recorder according to the present invention uses a DC servo motor to record changes in process quantities on recording paper with a recording pen, and is powered by a commercial power source. 2 power supply and battery power supply for power outage
a power outage detection circuit that detects a power outage in the commercial power supply, and a power outage detection circuit that detects a power outage in the commercial power supply; when a power outage is detected by the circuit, the power supply is switched to the battery power supply, and the power supply from the battery power supply to the servo motor is controlled for a certain period according to a signal from the transmitting circuit; and a switching circuit that supplies the power intermittently.

[Function] The present invention is designed to drive and control the servo motor intermittently at a constant cycle during a power outage. Specifically, when a power outage is detected, the power that was previously continuously supplied to the servo motor will be supplied by a switching circuit for one second every 16 seconds, for example. It has a built-in oscillation circuit to operate the switching circuit for only 1 second every 16 seconds.

[Example] In FIG. 1, the oscillation circuit 19 always outputs a signal that operates for 1 second every 16 seconds, and when a power failure detection signal is now transmitted from the power failure detection circuit 18 to the switching circuit 17, the servo motor The power from the battery 15 supplied to 2 will be stopped for 15 seconds and will be supplied for 1 second. Incidentally, since the temperature control process generally has a slow response, this degree of intermittent operation (recording) does not pose any practical problem.

[Effects of the invention] According to the invention, since the DC servo motor of the self-balancing recorder is configured to be operated intermittently by the battery power supply during power outages at a certain period, it is not necessary for conventional continuous operation. The battery capacity of the present invention is much smaller than that of the conventional battery, and therefore, assuming the same operating (recording) period during a power outage, the device to which the present invention is applied can be small, lightweight, and inexpensive. effective.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a main part showing an embodiment of the present invention, and FIG. 2 is a mechanical diagram of a conventional automatic balancing recorder. 1...Amplifier, 2...Servo motor, 10...
Power supply circuit, 15... battery, 16... charger,
17... Switching circuit, 18... Power failure detection circuit, 19... Oscillation circuit.

Claims (1)

[Scope of utility model registration request] An automatic balancing recorder that uses a DC servo motor to record changes in process quantities on recording paper using a recording pen, has two power sources: a commercial power source and a battery power source for power outages, and detects power outages in the commercial power source. A power outage detection circuit; and a switching circuit that switches to the battery power supply when a power outage is detected by the circuit and intermittently supplies power from the battery power supply to the servo motor at a certain cycle based on a signal from a transmitting circuit. An automatic balancing recorder characterized by: