JPS5840433A - High-frequency heater - Google Patents

Abstract

PURPOSE:To enable materialization of a highly safety device for opening and closing a door, by making a device into such a simple construction that an electric power source for an electric motor is turned off before the door is closed completely, and after that closing action of the door is completed by tension of a spring installed on a door arm. CONSTITUTION:A door 8 which opens and closes by making a hinge 12 provided in the vicinity of the bottom of the inside of a main body housing 1 into a fulcrum is provided to open and close an opening part of a heating chamber 3 provided inside the main body housing 1. An arm 14 which is connected with a position of the door 8 located between the top face of the door 8 and the hinge part 12 so that a setting angle of an opening and closing direction of the door against the door becomes free. Then, a spring 18 which acts in a closing direction of the door 8 between the arm 14 and the main body housing 1 in the main body housing 1 is provided, an electric motor 20 is provided in the main body housing 1, and the door 8 is opened and closed by the electric motor 20 through the arm 14. In a course of closing the door 8, an electric power source for the electric motor is turned off by a switch 27 before the door 8 is closed completely, in that high-frequency heater.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure in which a door is opened and closed by an electric motor, and its purpose is to improve safety.

Conventionally, when heating an object in a high-frequency heater,
Generally, the operator operates a knob provided on a part of the door to open the door. Therefore, when holding an object to be heated in both hands, it is necessary to put the object down and open the door7, or to open the door in advance. A particularly busy diner.

This often happens in situations where the device is used for business purposes such as restaurants. One of the themes of this type of cooking utensil is to improve the efficiency of cooking operations. 1
How long it takes to complete one heating task is an important factor.Under these circumstances, we focused on opening and closing the door in order to shorten the cooking time, and when holding the object to be heated in both hands. However, a door opening/closing device has been devised that uses a foot switch to open and close the door using an electric motor. However, this door opening/closing device is extremely dangerous and poses a safety problem when someone gets their hand caught in the door.

Therefore, the present invention solves the above-mentioned conventional drawbacks by turning off the power to the electric motor before the door is completely closed, and then completing the closing operation using the tension of the spring attached to the door arm. This makes it possible to realize a door opening/closing device with a highly safe structure. Examples thereof will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic side cross-sectional view of the main body of the high-frequency heating device. A heating chamber 3 for heating an object 2 to be heated is provided in the main body 1 . An opening 6 formed in a part of the upper wall 4 is arranged in the heating chamber 3, and a waveguide 7 for guiding radio waves emitted by a magnetron 6 as a high-frequency heating device is connected to this opening 5. There is an operation section 56 on the front upper part of the main body that controls the input of the magnetron 6.
The structure is designed to enable high-frequency heating. These means are the same as before, and we will not discuss the details. A door 8 is provided at the front of the heating chamber 3 to allow the object to be heated 2 to be taken in and taken out.

The door 8 is provided with a handle 9 for easy opening and closing, and has a support part 10 at a vertical angle, and a hinge 12 having a coupling hole 11 in a part of the support part 1° is attached to the door. It is fixed on the surface side. On the other hand, the door 8 is provided with a metal fitting having a hole in the part opposite to the coupling hole 11 of the support part 1o, and by passing the shaft between the coupling hole 11 of the hinge 12 and the hole of the door metal fitting. The door 8 is pivotally supported by a hinge 12, and the door 8 is parallel to the front wall 13 of the heating chamber with the coupling hole 11 of the hinge 12 as the center, which is a so-called closed state, to an open state having a certain angle. ing.

Note that a pair of metal fittings for the hinge 12 and the door 8 are provided on the left and right sides at the same height from the lower end surface of the door 8. Between the mounting part of the door 8 on the support part 10 of the hinge 12 and the upper end surface of the door 8, the mounting angle with respect to the opening/closing direction of the door 8 is freely adjustable, and the opening/closing angle of the door is parallel to the support part 1° of the hinge 12. An arm 14 for regulation is provided. In order to make the mounting angle flexible, a metal fitting 16 with a surface parallel to the supporting part 10 of the hinge 12 is provided on a part of the door, and this metal fitting 16 allows the doors 1o and 6 to be attached to each other.
- The arm 14 is connected by a shaft 16. Arm 14
The length is such that the angle that the door 8 makes with the front wall 13 of the heating chamber is at least a right angle, and the end surface opposite to the side where it is connected to the door 8 has a length that is suitable for the front wall 13 of the heating chamber. The coil spring 18 is inserted into the main body through the hole 17 provided in the main body.
The other end of the coil spring 18 is connected to the inside of the main body. By appropriately setting the constant of the coil spring 18, the operating force required to open and close the door 8 can be freely selected. A guide roller 19 is attached to the upper end of the hinge 12 to support and guide the arm.

An electric motor 20 is fixed inside the main body, and this electric motor 2o is a capacitor phase added type AC motor, and can be operated in either forward or reverse direction by switching the polarity of the voltage applied to the coil on the side where the capacitor is connected. It also has a structure that allows it to rotate.

Further, the output shaft of the electric motor is fixed to a drive lever 22 via an electromagnetic clutch 21, and the drive lever 22 is connected to the arm 1.
It is linked to 4. Electric motor 20 control device 2
3, its rotation is controlled. The operation of the control device 23 will be described later. A lead wire 24 is provided from the control device 23, and is connected to a foot switch 25 having a normally open contact point that allows the operator to operate the control device 23 with his or her foot. When the foot switch 26 is stepped on (closes the contact) while the door 8 is closed, the electromagnetic clutch 21 is connected, and the door 8 is opened by the electric motor 2o via the drive lever 22 and the arm 14. When the door 8 is fully open, the normally closed contact limit switch 2
6 is an open contact, the shimmo motor 2° stops, and the electromagnetic clutch 21 is also disengaged. The door 1o is fully opened and the heated object 2 enters the heating chamber 3.
When the foot switch 26 is pressed again after the operation to turn on or take out the door 8, the electromagnetic clutch 21 is connected and the electric motor 20 is rotated in the opposite direction due to the configuration of the control device 23. is closing. When the door 8 closes to a certain extent, the normally closed contact switch 27 becomes an open contact, the power to the electric motor 20 is cut off, and the electromagnetic clutch 2 is turned off.
1 is cut off. Further, the arm 14 is tensioned by a spring 18, and the tension of the spring 18 completely closes the door 8. In this way, the power to the electric motor 20 is turned off before the door 8 is completely closed, so it is safe even when an object or hand is caught.

In this embodiment, the control device 23 is a combination of a relay and a switch, and its circuit is shown in FIG. The configuration and operation will be explained below. When the main switch 28 is turned on, the alternating current power supply necessary for the operation of the main body is simultaneously supplied to the control device. The foot switch 26 is connected in series to the relay A29 and the power supply. When the foot switch 26 is turned ON by stepping on it, the contact 30 of the relay A 29 is closed and the relay is self-held.

At the same time, the contact 31 is closed and voltage is applied to the main coil 32 of the motor 20. Another coil 33 of the motor 2o is connected in series with a phase addition capacitor 34, and when the contact 31 is closed, the motor 20 starts rotating in the direction of the contact by the contacts 35 and 36. In the present invention, the doors 35 and 36 are connected to the power supply. Even if the operator stops operating the foot switch 26, this operation continues because the self-holding contact 3o remains ON. When the door 8 is fully opened, the limit switch 26 is turned on, power is supplied to the relay "37, and its normally closed contact 38 is turned on.
is open and the normally open contact 39 is closed. Since it is connected in series with the relay 29, the power supply to the relay 29 is stopped at this point, and as a result, the contacts 30 and 31 are turned off, and the rotation of the motor is stopped. Furthermore, the following operations are performed inside the control device 23.

The normally open contact 39 of the relay 37 is turned on, and the delay circuit 4° starts operating. The delay circuit has the configuration shown in Fig. 3, and when an AC voltage is applied to the input, the C4 voltage applied to the C42/R/43 integrating circuit is rectified by the diode 41.
The terminal voltage of No. 2 starts to gradually rise from Ov with a time constant determined by C.H. A relay 44 and a bidirectional thyristor 46 connected in series are connected in parallel to the capacitor C42, and when the voltage of the capacitor C42 exceeds the breakover voltage of the bidirectional thyristor 45,
The bidirectional thyristor 45 is turned on, and a discharge current due to the charge of the capacitor 42 flows through the relay 44 . At this time, the contact 45 of the relay 44 is turned on, and after that, power is supplied to the relay 44 through its own contact 45 and a resistor 46 that determines the holding current value, and the normally open contact 47 continues to be turned on until the power supply voltage is cut off. . That is, the time from when a voltage is applied to the delay circuit until the output contact 47 is closed is arbitrarily set by the charging time constant formed by the combination of the capacitor C42 and the resistor R43, and the time from when the aforementioned contact 39 is turned on is set for a certain period of time. After connecting the holes, the contact 47 is turned ON. The contact 47 is the switching contact 3 that determines the rotation direction of the motor 20.
Q is connected in series with the coil of the drive relay 48 of 5.36, and when the contact 47 is turned on, the switching contacts 57 and 58 switch the circuit so that the polarity rotates in the opposite direction. At the same time, a contact 49 provided in parallel with the contact 38 and a contact 6o provided in parallel with the contact 47 are also turned on. At this point, the motor 20 is now ready to rotate in the opposite direction by 10 bases. Furthermore, the operator steps on the foot switch 26 again (turns ON) after the door 8 is opened and the object to be heated 2 has been taken out and put into the heating chamber 3 of the main body.
and relay 29 are self-held by contact 3o, and contact 31
The υ motor 20 in the fr′○N state starts to rotate in reverse. The claw 9 door 8 begins to close. When the door 8 begins to close, the switch 26 turns OFF, the power to the relay 37 is turned off, and the contact 38 turns ON, but since the contact 49 is already ON, there is no change. Further, the contact 39 is turned off, but the delay circuit 40 is powered off, and the contact 47 is turned off, but the relay 48 is already held by the contact 50. When the door closes to a certain extent, the switch 27 is turned on. The switch 27 supplies power to a relay 51 provided in the control device 23, and one of the normally closed contacts 52 of the relay 51, which is turned ON at that time, is connected in series with the self-holding contact 3o of the relay 29. Another normally closed contact 63 is relay 4
Since it is connected in series with 8, when this relay 51 is turned on, the self-holding of the relay 29 is released and the contact 31 becomes 11.
At the same time, the motor stops and the power to the electromagnetic clutch 64 is also turned off, and the club and tip are cut off. Although the door 8 is in the process of closing, the arm 14 is being pulled by the coil spring 18, and the door 8 is completely closed by the tension of the coil spring 18. The switch 27 continues to be turned on even when the door 8 is completely closed. Turn foot switch 26 and switch 27 OFF again.
When the switch is depressed (turned ON), the relay 61 is turned OFF, the relay 29 is turned ON in a self-holding manner, and the operation continues until the door 8 is completely opened and the switch 26 is turned ON. Below, the above operation will not be changed.

According to the above configuration, the power to the electric motor is turned off while the door is completely closing, and the closing operation of the door is then completed by the tension of the coil spring attached to the door arm, so the user may accidentally touch the door. It is extremely safe even when pinched. Furthermore, since the power to the electric motor is turned off before the door is completely closed, the drive mechanism is not strained and its durability can be improved.

This embodiment has also been explained regarding a door opening/closing device operated by a foot switch.
-40433 (4) It goes without saying that the same applies to the door opening/closing device provided on the operation panel. Also, since the door is opened and closed by an electromagnetic clutch except when it is driven by an electric motor, there is no effect on manually opening and closing the door. Traditionally, if you could open and close the door by operating it with your foot, it would be convenient when you have food in both hands, and you would not have to worry about getting an electric shock if your hands got wet or dirty while cooking. Several door opening/closing devices have been devised to meet this demand, but they have had problems in terms of safety.

The present invention dramatically improves safety with a simple configuration and solves and realizes such problems.

[Brief explanation of the drawing]

Fig. 1 is a schematic side cross-sectional view of the main body of a high-frequency heating device showing one embodiment of the present invention, Fig. 2 is a circuit diagram of the same embodiment, and Fig. 3 is a second
It is a circuit diagram of the delay circuit in a figure. DESCRIPTION OF SYMBOLS 1... High-frequency heating device main body, 2... Heated object, 3... Heating chamber, 8... Door, 9
...Handle, 10..., ...Hinge support part, 11...-Hinge support part coupling hole, 12...
... Hinge, 13 ... Heating chamber front wall, 141
3' knee. ...Arm, 16...Support fitting, 16
....Connection shaft, 17..Hole for arm retraction, 18..Coil spring, 19..Guide roller, 2Q.....Electric motor. , 21...
...Electromagnetic clutch, 22...Kawa/m shift v par, 23
...Control upper position, 25...7 switch, 26...Normally open contact limit switch, 27
・・・・・・Normally open contact switch, 28: Normally open contact main switch, 29: Relay A, so
...Relay A normally open contact. 31... Relay A normally open contact, 32...
Motor main coil, 33...Motor coil. Name of agent: Patent attorney Toshio Nakao (1 person)

Claims (1)

[Claims] (1) A main body with a heating chamber inside, a hinge part near the lower end to open and close the opening of the heating chamber, and a door that opens and closes using this hinge part as a fulcrum, and the upper end surface of the door It has an arm that is connected between the hinge parts so that the mounting angle in the opening and closing direction of the door can be freely adjusted, and that is provided so that it can freely move in and out of the main body. A spring acting in the direction of A high-frequency heating device equipped with a switch to turn it off.偻) The high-frequency heating device according to claim 1, wherein the output shaft of the electric motor is provided via a clutch.