JPS621728Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrical device with a built-in timer device, which is equipped with an alarm that notifies when the timer device has finished driving a load.

For example, in a dryer, a timer device including a cam plate rotated by a timer motor and a plurality of cam switches opened and closed by the cam plate is installed, and a time limit set by the dryer operating circuit via a predetermined cam switch is installed. The drying operation is carried out during the drying operation, and after the drying operation is completed, a buzzer is energized via another cam switch to sound to notify the end of the drying operation. However, since such a timer device has a structure in which the cam switch is closed by a cam plate, it is impossible to set the closing time of the cam switch for buzzer sound to less than 2% of the maximum time limit of the timer device. Therefore, like a dryer, the maximum time limit is
In the case of a long period of about 120 minutes, the buzzer sounding time cannot be shortened that much.
This has the disadvantage that the buzzer continues to ring for an unnecessarily long time, which is annoying to the ears. For this reason, conventionally, as a timer device, its maximum time limit is
It is possible to set the closing time of the cam switch for buzzer sound to a short time of 30 seconds or less, and an external drive circuit is provided to intermittently energize the timer motor of the timer device. A configuration is being used to extend the practical maximum time of the timer device to about 120 minutes. However, such a conventional configuration has the problem that it requires an external drive circuit, which complicates the overall structure, and that the set time limit value is likely to deviate due to variations in the characteristics of the external drive circuit. Another problem is that the drying operation time is not constant.

The present invention was made in view of the above circumstances, and its purpose is to be able to arbitrarily shorten the notification time of the alarm regardless of the maximum time limit of the timer device, and to improve the overall structure. To provide an electric device with a built-in timer device which has effects such as not complicating the timer device and also preventing the time limit value set in the timer device from going out of order.

Hereinafter, a first embodiment in which the present invention is applied to a rotary drum dryer will be described with reference to FIGS. 1 and 2. In Fig. 1 showing the operating circuit of a dryer, 1 is a timer device that starts timed operation for up to 120 minutes in response to a time setting operation. It consists of three cam switches 3, 4 and 5 which are operated by a cam plate. In such a timer device 1, each of the cam switches 3, 4, and 5 is closed during the period shown by the diagonal line in the time chart of FIG. 2, and the time limit operation time can be arbitrarily set within a range of up to 120 minutes. It's becoming like that. In addition, in FIG. 2, the remaining time of the timed operation is shown on the horizontal axis. Reference numeral 6 denotes a power source, one end of which is connected to the bus bar 7, and the other end of which is connected to the bus bar 8 via the door switch DS and the cam switch 3, which are configured to close in conjunction with the closing of the door. A timer motor 2 is connected between 8 and 8. Reference numeral 9 denotes a dryer driving motor (corresponding to the load of the present invention), and a series circuit consisting of this and the cam switch 4 is connected between bus bars 7 and 8. The motor 9 is
This is a well-known structure in which when the rotary drum is energized and driven, the rotary drum is rotated via the belt transmission mechanism, and at the same time, a blower fan for blowing air into the rotary drum is also rotated. A heater 10 is connected in series with a cam switch 5 between the busbars 7 and 8, and is arranged in the air passage of the air blower fan to heat the air blown into the rotating drum.
Therefore, when both the motor 9 and the heater 10 are energized, a so-called hot air drying process is executed in which hot air is supplied to the inside of the rotating drum while rotating it, and when only the motor 9 is energized, the rotating drum A so-called cold air drying process is performed in which cold air is supplied to the inside of the dryer while rotating it. 11 is a capacitor for charging and discharging, one end of which is connected to the bus bar 7, and the other end connected to the resistor 1.
The cam switch 4 is connected to a common connection point between the motor 9 and the cam switch 4 through a series circuit of a diode 13 having the polarity shown in the figure. Then, a series circuit of resistors 14 and 15 is connected in parallel with the capacitor 11, and the resistor 1
A common connection point between transistors 4 and 15 is connected to the base of a transistor 16 which is a switching means. Also,
The emitter of the transistor 16 is connected to the bus bar 7, and the collector is connected to the excitation coil 17a of the relay 17, the resistor 18, and the diode 19 with the polarity shown.
It is connected to the bus bar 8 through a series circuit. 20 is a buzzer serving as an alarm for notifying the end of the drying operation consisting of the hot air drying process and the cold air drying process described above, and this and the normally open contact 17 of the relay 17.
A series circuit with the cam switch 4 is connected in parallel with the cam switch 4.

Next, the operation of the above configuration will be explained. When the time setting operation of the timer device 1 is performed and the time limit operation time is set to 120 minutes, for example, with the material to be dried in the rotating drum, the door closed, and the door switch DS closed, Cam switch 3, 4, 5
are all closed. Therefore, timer motor 2
is energized to start the timed operation of the timer device 1, and at the same time, the motor 9 and the heater 10 are both energized and the hot air drying process is started. When the hot air drying process is started and the motor 9 is driven, the capacitor 11 is charged to the polarity shown through the cam switch 4 and the diode 13, so the transistor 16 is connected to the common connection between the resistors 14 and 15. It is biased on by the voltage appearing at the point. Therefore, in this case, the excitation coil 17a of the relay 17 is energized and its normally open contact 17b is closed, but at this time the buzzer 20 is short-circuited by the cam switch 4 and does not ring. Thereafter, when the hot air drying process continues and the timed operation time of the timer device 1 reaches 10 minutes,
The cam switch 5 is opened, the heater 10 is cut off, and the cold air drying process is started. When the cam switch 4 is opened after another 5 minutes, a series circuit of the motor 9, the normally open contact 17b, and the buzzer 20 is formed. In this case, the buzzer 20 only needs a small output and its load current is small, and the motor 9 has a relatively large current flowing through it, so as a result, the impedance of the buzzer 20 is larger than that of the motor 9. Become. As a result, the shared voltage of the motor 9 drops below the voltage sufficient to drive it, so the motor 9
is stopped and the cold air drying process is completed, and at the same time, the buzzer 20 is energized and sounds to notify the end of the series of drying operations consisting of the hot air drying process and the cold air drying process. On the other hand, the capacitor 11 starts discharging via the resistors 14 and 15 at the same time as the cam switch 4 is opened and the motor 9 is stopped.
When a predetermined period of time has elapsed from the start of the discharge, the transistor 16 is turned off and the normally open contact 17b is opened, and at this point the buzzer 20 stops sounding. Incidentally, the sounding time of the buzzer 20 can be set to an arbitrary short time by appropriately selecting the capacitance of the capacitor 11 or the resistance values of the resistors 14 and 15. Then, five minutes after the cam switch 4 is opened as described above, the cam switch 3 is opened and the drive of the timer motor 2 is stopped, thereby stopping the timer operation of the timer device 1.

According to the present embodiment described above, the capacitor 11 is provided which is charged when the motor 9 is driven and which starts discharging in response to the opening operation of the cam switch 4 for turning on/off the motor 9, and the charging voltage of the capacitor 11 is A transistor 16 that is turned on by the transistor 16 and a relay 17 that is energized and driven by the turning on of the transistor 16 are provided, respectively, and a series circuit of the normally open contact 17b of the relay 17 and the buzzer 20 is connected in parallel with the cam switch 4. With this structure, the buzzer 20 can be sounded at the same time the cam switch 4 is opened and the drying operation is ended, and the duration of the buzzer can be set to an arbitrary short time depending on the discharging time of the capacitor 11. That is, according to this embodiment, since the buzzer is not configured to sound by a cam switch in the timer device as in the conventional case, the ringing time of the buzzer 20 can be arbitrarily set regardless of the maximum time limit of the timer device 1. It can be shortened and the ringing sound can be prevented from becoming harsh on the ears. Further, in this embodiment, an external drive circuit for the timer motor 2 is not required, and therefore the overall structure is not complicated.
Alternatively, the time limit value set in the timer device 1 does not tend to deviate as in the conventional case, and the drying operation time can be set accurately.

By the way, FIG. 3 shows an operating circuit for a dryer that was considered separately from the one in FIG. 1 during the development process of the present invention, with the same functional parts as in FIG. 1 being given the same reference numerals. The relay 17 has a normally closed contact 17c. In such a configuration, when the cam switch 4 is closed and the motor 9 is driving, the transistor 16 is off and the normally closed contact 17c is closed, but the buzzer 20 is shorted by the cam switch 4. It does not make a sound when it is in a closed state. After that, when the cam switch 4 is opened, the buzzer 20 sounds and the capacitor 11 starts charging.
When a predetermined period of time has elapsed since the start of charging, the transistor 16 is turned on and the excitation coil 17a of the relay 17 is energized, thereby opening the normally closed contact 17c and stopping the buzzer 20 from ringing. Therefore, even with such a configuration, the same effects as in this embodiment described above can be obtained. However, in the above configuration, after the buzzer 20 stops sounding, the door opening/closing operation, that is, the door switch DS
When the door switch is opened and closed, the door switch
When DS is open, capacitor 11 connects to resistors 14 and 15
The transistor 16 is turned off by discharging through the
Since the normally closed contact 17c is now closed, there is a drawback that the buzzer 20 will beep again unnecessarily when the door switch DS is subsequently closed. In contrast, in this embodiment, the capacitor 11 is configured to start discharging when the cam switch 4 is opened, so the door switch is activated after the buzzer 20 stops sounding.
Even if the DS is opened or closed, the buzzer 20 will not ring again as in the configuration shown in FIG. 3 above.

FIG. 4 shows a second embodiment of the present invention in which the circuit connections in the first embodiment are partially changed, and this will be described below. That is, one end of the capacitor 11 is connected to the bus bar 7 through a series circuit of a resistor 12 and a diode 13 with the polarity shown, and the other end is connected to a common connection point between the motor 9 and the cam switch 4. A series circuit of resistors 14 and 15 is connected in parallel with 11.
Then, the emitter of the transistor 16 whose base is connected to the common connection point of the resistors 14 and 15 is connected to the common connection point of the motor 9 and the cam switch 4, and its collector is connected to the excitation coil 1 of the relay 17.
7a, a resistor 18, and a diode 19 having the illustrated polarity. Further, a series circuit consisting of a normally open contact 17b of the relay 17 and a buzzer 20 is connected between the bus bars 7 and 8.

According to this configuration, during drying operation in which the cam switch 4 is closed and the motor 9 is energized, the capacitor 11 is charged and the transistor 16 is turned on. However, in this case, since the excitation coil 17a of the relay 17 is short-circuited by the cam switch 4, the normally open contact 17b remains open, and the buzzer 20 does not sound. After that, when the cam switch 4 is opened, a series circuit is formed between the excitation coil 17a, the collector and emitter of the transistor 16, and the motor 9, so the motor 9 is stopped and the drying operation is completed, and the excitation coil 17a is energized. As a result, the normally open contact 17b is closed and the buzzer 20 is energized and sounds, and the sound continues for a predetermined period of time until the transistor 16 is turned off, as in the first embodiment. Therefore, in the second embodiment having such a configuration, the same effects as in the first embodiment can be obtained.

FIG. 5 shows a third embodiment of the present invention, and only the parts different from the previous embodiments will be explained below. That is, a series circuit of a diode 22, a resistor 23, and a capacitor 24 with the polarity shown is connected between the bus 7 and the auxiliary bus 21, and a diode with the polarity shown is connected between the common connection point of the motor 9 and the cam switch 4 and the auxiliary bus 21. 25, resistance 26 and 2
Connect 7 series circuits. In addition, the capacitor 24
A series circuit between the resistor 28 and the collector-emitter of the transistor 29 is connected in parallel with
Similarly, a series circuit between a resistor 30 and the collector-emitter of another transistor 31 is connected in parallel with the capacitor 24. Then, the base of the transistor 29 is connected to the common connection point of the resistors 26 and 27, and the base of another transistor 31 is connected to the collector of the transistor 29 via the charging/discharging capacitor 32, and the common connection point of the resistors 28 and 30 is connected. A resistor 33 is connected between the connection point and the base of the transistor 31. On the other hand, 34 is a full-wave rectifier circuit, one AC input end 34a of which is connected to the common connection point of the motor 9 and cam switch 4 via the buzzer 20, and the other AC input end 34b connected to the bus bar 8. Further, one DC output end 34c of the full-wave rectifier circuit 34 is connected to the auxiliary bus bar 21 via a thyristor 35, which is a switching means of the illustrated polarity, and the other DC output end 34d is connected to the auxiliary bus bar 21. Therefore, in effect, the series circuit of the buzzer 20 and the thyristor 35 is connected in parallel with the cam switch 4. The gate of the thyristor 35 is connected to the collector of the transistor 31.

In this configuration, during drying operation in which the cam switch 4 is closed and the motor 9 is energized, the resistors 26 and 27 are short-circuited by the cam switch 4 and the transistor 29 is turned off. Therefore, in this case, the capacitor 32 is charged to the illustrated polarity state via the resistor 28, and at the same time the transistor 31 is turned on and the thyristor 3 is turned on.
5 is turned off. Thereafter, when the cam switch 4 is opened, the transistor 29 is turned on and the charge in the capacitor 32 is discharged, so that the base potential of the transistor 31 becomes approximately zero and the transistor 31 is turned off. For this reason,
At the same time as the cam switch 4 is opened, the thyristor 35 is turned on and the motor 9, the buzzer 20 and the thyristor 3 are turned on.
5 is formed in series, the motor 9 is stopped and the drying operation is completed, and the buzzer 20 is activated.
is energized via the full-wave rectifier circuit 34 and the thyristor 35, and the buzzer starts sounding. On the other hand, the capacitor 32 is connected to the low resistance 33 at the same time as the cam switch 4 is opened and the motor 9 is stopped.
The transistor 31 is recharged in the opposite direction to the illustrated polarity state through the transistor 29, and when a predetermined time has elapsed from the start of recharging, the base potential of the transistor 31 reaches a certain value and is turned on, thereby turning off the thyristor 35. The buzzer 20 stops sounding. Therefore, the same effects as in the first embodiment can be obtained in the third embodiment having such a configuration.

According to the present invention, as explained above, the notification time by the alarm can be arbitrarily shortened regardless of the maximum time limit of the timer device, and the overall structure does not become complicated. Furthermore, it is possible to provide an electric device with a built-in timer device that has the effect that the time limit value set in the timer device does not go out of order.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram showing a first embodiment of the present invention, Fig. 2 is a time chart of a timer device in the same embodiment, and Fig. 3 is an electrical circuit diagram shown for comparison with the above first embodiment. , FIG. 4 is an electric circuit diagram showing a second embodiment of the present invention, and FIG. 5 is an electric circuit diagram showing a third embodiment of the present invention. In the figure, 1 is a timer device, 2 is a timer motor, 3, 4 and 5 are cam switches, 9 is a motor (load), 11 and 32 are capacitors, 16 is a transistor (switching means), 20 is a buzzer (alarm), 35 is a thyristor (switching means).

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A cam switch that drives a load during a set time and stops driving the load by opening the cam switch, and an alarm that notifies when the drive of the load is stopped. A capacitor is provided to be charged when the load is driven and to start discharging in response to the opening operation of the cam switch, and the alarm is energized and driven in response to the start of discharging of the capacitor, and the energization drive time. 1. An electric appliance with a built-in timer device, characterized in that it is provided with switching means for controlling the discharge time or recharging time of the capacitor. 2. The electric device with a built-in timer device according to claim 1, wherein the load is a motor for driving a dryer.