JPS6238810B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a time switch for switching a watt-hour meter by time zone, and particularly to improvements in its driving method and driving mechanism.

In general, a time switch that switches the signal from a power meter for each time period such as peak, off-peak, or night time switches the load directly to the power meter or maximum demand power display for each time period.
Relay circuits are used, but a crystal clock circuit with high time accuracy is used for the time transmitter that issues time signals to control these relay circuits for each set time period.

There is also a method of constantly rotating a step motor in response to a signal from a crystal clock, and using the output of this step motor to rotate the time setting dial plate, but this method consumes less power because the step motor, which consumes a large amount of power, is constantly driven. If the power outage compensation time is large and the power outage compensation time is extended, a large storage battery is required. Furthermore, when a dial plate is rotated by decelerating the rotation of a step motor that is constantly driven, and a setting claw attached to the dial plate is used to open and close a microswitch, the timing at which the microswitch opens and closes with respect to the gradually advancing setting claw is constant. Therefore, in order to perform accurate switching, the timing must be set by superimposing it on another time signal.

Another method is to operate an electromagnet using a time signal from a crystal clock, and use the attraction force of this electromagnet to rotate the ratchet wheel and rotate the dial, but in this case, the circuit cannot be switched instantly by the attraction force of the electromagnet. However, if a mechanical gap is required between the ratchet wheel feed and the reversal prevention pawl, and the set time interval is small,
In order to create a margin for operation in this gap, it is necessary to make the dial plate large and increase the rotational displacement of the dial plate in response to the timed pulse, but if the dial plate is made large, the rotational inertia increases and a large impact force is generated. There are problems such as the need for additional mechanical strength.

An object of the present invention is to provide a time switch that improves the above-mentioned problems.For this reason, in the present invention, only the clock circuit is operated at all times to reduce power consumption, and the clock circuit is operated at all times for a short period of time. For example, operate the step motor for about 1 second every 15 minutes to instantaneously rotate the dial plate.
At the set time, the cam mechanism instantly opens and closes the circuit switching micro switch, and the cam mechanism changes the open/close state of the micro switch so that when the opening claw passes, the circuit remains open, and when the closing claw passes, the circuit remains closed. maintain the condition. Since the rotational force of the step motor rotates the dial plate via the worm gear mechanism, the instantaneous rotational impact force of the step motor is replaced by an axial force on the dial plate due to the torsion angle of the worm, so that the dial plate rotates. The impact force in the direction can be made small, and the gap in the rotating direction of the dial plate can also be made small by making the tooth surface gap between the worm and the worm gear small, so the rotational gap can be made small, and even when the set time interval is small, there is sufficient operating margin. He achieved his intended purpose by creating a time switch equipped with a mechanism that allows for

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block connection diagram showing a drive circuit of an embodiment of a time switch according to the present invention, FIG. 2 is a time chart showing timing states of the drive circuit of FIG. 1, and FIG. FIG. 3 is a perspective view schematically showing the drive mechanism of the time switch.

In FIG. 1, a high frequency pulse from a crystal oscillator 1 having a high oscillation frequency is frequency-divided by a frequency dividing circuit 2 to more than ten Hz. This frequency-divided pulse is counted by a counter 3, and each time this counted value reaches the set time limit of the time switch (for example, 15 minutes, 30 minutes, 60 minutes), the time limit circuit 4 outputs a time limit pulse, and also outputs a time limit pulse for a certain short time. Then, the power supply of the step motor drive circuit 5 is closed. The step motor drive circuit 5, which generates two-phase pulses for operating the step motor 6, is energized for the aforementioned short period of time and operates only during this period, causing the step motor 6 to rotate. Power to these circuits and the step motor is normally supplied from an AC power source through a constant voltage circuit 8 including a transformer 7 and a rectifier, but during a power outage, power is supplied from a storage battery 9, and when power is re-energized after a power outage, the power is supplied from the storage battery 9. is charging circuit 10
The power supply unit is configured to be charged by.

Next, a time chart for a 15 minute time limit will be explained with reference to FIG. A signal from a crystal oscillator 1 having a high oscillation frequency of several MHz is frequency-divided by a frequency dividing circuit 2 to 16 Hz. This 16Hz frequency divided pulse is sent to counter 3.
The timer circuit 4 outputs a timer pulse every time it counts divided pulses equivalent to 15 minutes (14,400 pulses) and closes the power supply of the step motor drive circuit for a certain short time. The step motor drive pulse sent by the step motor drive circuit 5 is a 16Hz frequency divided pulse shifted by half a pulse to make it into two phases, and the pulse width is 8Hz. It was synthesized by combining them. The power supply to the step motor drive circuit 5 is turned on for the time it takes to transmit these two-phase pulses to the nine pulses necessary for one revolution of the step motor 6, that is, 1.125 seconds (power pulse in the time chart). With this configuration, only the frequency divider circuit 2 and counter 3, which consume less power, are operated at all times, and the step motor, which consumes more power, is driven for about 1 second every 15 minutes to operate the mechanical parts. power consumption can be significantly reduced.

Next, the drive mechanism will be explained with reference to FIG. 1
1 is a step motor driven by the above-mentioned two-phase pulse; 12 is a gear attached to the rotor shaft of the step motor 11; 13 is a gear fixed to a shaft 14;
15 is a worm attached to the shaft 14, and 16 is a worm gear 1 at one end.
7 and a time setting dial plate 19 is attached to the other end. As shown in FIG. The dial plate 19 is provided with a screw hole 20 in which a time setting pawl 23 is fixed with a screw 22. Two claws, one for opening the circuit 23 and one for closing the circuit 24, turn on and off one switch. The cams 27a and 27c are fixed to a spacer 27b, and the spacer 27b is inserted into the shaft 38 so as to rotate freely. Further, a lever 30a of a micro switch 30 is held in contact with the cam 27a, and a stopper spring plate 32 is in contact with the cam 27c. The cams 27a and 27c are fixed in a state where they are rotationally displaced by half of one tooth.

Next, the operation will be explained. As mentioned above, a pulse necessary for the rotor shaft to rotate once is applied to the step motor 11 for about 1 second every 15 minutes,
As a result, the step motor 11 rotates only one revolution in about one second every 15 minutes. This step motor 11
The rotation amount is 1/ by gears 12, 13, 15, 17.
Decrease the speed to 96 and turn the time setting dial plate 19 to 15.
Rotate by the amount of rotation equivalent to 1 minute. A claw 23 for opening the microswitch 30 and a claw 24 for closing the microswitch 30 are attached to the dial plate 19 for time setting, and the rotation of the claw 23 or 24 rotates the cam 27a or 27c. cam 27
a and 27c and micro switch lever 30a
The relationship with the spring plate 32 is that of the dial plate 19.
By rotating by a rotation amount equivalent to 15 minutes, the cam 27a is rotated by half a tooth via the opening pawl 23, and the lever 30a of the micro switch 30 is dropped into the valley of the cam 27a, thereby opening the micro switch 30. At this time, the cam 27c installed with a rotational displacement of half a tooth
The spring plate 32 is located at the peak of the cam, and the cam 2
7c is held in the counter-rotational direction by a spring force, and this rotational force is stopped at the tip of the lever 30a of the micro switch 30, so this state is maintained. Next, when the circuit closing pawl 24 comes and rotates the cam 27c by half a tooth, the spring plate 32 falls into the valley of the cam 27c, and the cam 27a, which has been rotated by a half tooth from this position, is rotated by the micro switch. Lever 30a
is pushed up to the peak of the cam 27a, and the micro switch 30 is closed. The cam 27a receives a rotational force in the counter-rotation direction due to the pressure of the micro switch lever 30a pushed up, but the spring plate 32
Since it has fallen into the valley 7c, it is stopped at the tip of the spring plate 32 and this state is maintained. like this
The step motor is operated for about 1 second every 15 minutes, and the switch is switched during that 1 second operation, and after the switch is switched, the cam mechanism maintains that state, so the power required to maintain the circuit state is reduced. No consumption necessary. In addition, the reason why a worm and a worm gear mechanism are used as the speed reduction mechanism between the step motor 11 and the dial plate 19 is that when the step motor operates for a time shorter than 1 second, a speed reduction mechanism using spur gears is used. If this happens, the rotational impact force of the step motor causes the dial plate to over-rotate by an amount of backlash proportional to the reduction ratio of the gear, resulting in a drawback that the operational margin between the cam and the micro-switch becomes smaller. In the case of a worm gear mechanism, since the axes of the worm and the worm gear are orthogonal, the impact rotational force can be divided and reduced by the torsion angle of the worm, and the rotational play of the dial plate can be reduced, so the cam The micro switch has a large operating margin, which is advantageous when the setting interval of the claws is small.

Next, Fig. 4 shows a combination of two switch switching cam mechanisms shown in Fig. 3, in which the opening claws are 23 and 25, the closing claws are 24 and 26, and the opening cam is 27.
a and 29a, closing cams are 27c and 29
c. There are 2 spacers connecting the open circuit cam and the closed circuit cam.
7b and 29b, microswitches 30 and 35, and spring plates 32 and 36, the operating mechanism is as explained in FIG. The time switch with this configuration has two micro switches 30 and 3.
5 are connected as shown in FIG. 5, and the time slot of the day can be switched to time slots such as night time, peak time, and off-peak time.

As detailed above, according to the present invention, only the clock circuit is operated at all times, and the step motor is operated for a fixed short period of time at fixed time intervals to instantaneously rotate the dial plate, and the dial plate is rotated instantaneously at the set time. The cam mechanism opens and closes the microswitch to switch the circuit, and the cam mechanism keeps the microswitch open and closed until the next time setting claw arrives. Since the power consumption is reduced, it is possible to compensate for long power outages with a small-capacity storage battery, and the system can be made smaller. Furthermore, since the rotational force of the step motor rotates the dial plate via the worm gear mechanism, the instantaneous rotational impact force of the step motor is replaced by an axial force on the dial plate due to the torsion angle of the worm, and the rotation direction of the dial plate is In addition, since the gap in the rotating direction of the dial plate can be reduced, the gap between the tooth surfaces of the worm and the worm gear can be made small, so the rotation gap can be made small, and even if the set time interval is small, the operating margin of the cam and micro switch can be reduced. It is possible to provide a time switch that has many advantages such as being able to take a sufficient amount of time.

[Brief explanation of the drawing]

FIG. 1 is a block connection diagram showing a drive circuit of an embodiment of a time switch according to the present invention, FIG. 2 is a time chart showing timing states of the drive circuit of FIG. 1, and FIG. FIG. 4 is a sectional view showing a modified example of the circuit switching section; FIG. 5 is an electrical connection diagram showing the connection of the micro switch in the circuit switching section of FIG. 4. It is. 1... Crystal oscillator, 2... Frequency dividing circuit, 3... Counter, 4... Time limit circuit, 5... Step motor drive circuit, 6... Step motor, 8... Constant voltage circuit, 9... Storage battery, 11...Step motor, 19...Dial board, 23, 24, 25, 2
6...Time setting claw, 27a, 27c, 29a, 2
9c...Cam, 30, 35...Micro switch, 32, 36...Spring plate.

Claims (1)

[Claims] 1. A crystal oscillator, a frequency dividing circuit that converts the high frequency pulses from the crystal oscillator into a predetermined frequency, a counter that counts the frequency-divided pulses, and a time signal that outputs a time signal every fixed count of this counter. a time limit circuit that outputs a pulse that closes the power supply for a time; a step motor drive circuit that receives the power supply close pulse from the time limit circuit and converts the frequency-divided pulse into a two-phase pulse to intermittently drive the step motor; A power supply unit with power outage compensation that supplies power to each of the above-mentioned circuits, a gear mechanism including a worm gear that decelerates and transmits a constant rotation angle of the step motor, and a plurality of times that can be set to desired times. A dial plate having a setting pawl and instantaneously rotated by a rotation angle corresponding to the time limit by transmitting the rotation of the step motor through the gear mechanism, and the time setting pawl set on the dial plate. A time switch equipped with a cam mechanism that rotates and maintains its state, and a microswitch that switches a signal from a power meter at each time set by the time setting claw in response to the rotation of the cam mechanism.