JPS6037058Y2 - Cooker safety device - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a safety device for a cooker that has an extremely simple structure and prevents empty cooking when the pot is not stored.

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a main body of an electric cooking device such as a jar rice cooker, which includes a bottomed cylindrical outer pot 2 with an open upper surface, and a circumference between the outer pot 2 and the main body 1. A heat insulating material 3 wound around the side part, an inner pot 4 disposed so as to be suspended in the outer pot 2 so as to be freely inserted and removed, and rotatably attached to the main body 1 via a hinge section 5. It consists of a lid 6 that is closed and can open and close the top surface of the outer pot 2, and a heating element 7 for cooking rice, such as an annular sheathed heater, disposed at the inner bottom of the outer pot 2.

The inner bottom surface of the outer pot 2 bulges upward at approximately the center thereof to integrally form a bulge 8, and a through hole 9 is bored in the center thereof.

Further, a mounting plate 10 is fixed to the inner bottom back surface of the outer pot 2 at a distance from the bulged portion 8.

An insertion hole 11 is formed approximately in the center of this mounting plate 10 and at a position facing the through hole 9, and a through hole 12 is formed at a small distance from the insertion hole 11.

Reference numeral 13 denotes a heat-sensitive body case, which constitutes an outer shell of a flat heat-receiving plate 14, a cylindrical outer frame 15, and an electrically insulating support 16.

The outer periphery of the heat receiving plate 14 is bent downward to form a flange portion 14.
It forms a.

17 is a heat-sensitive element such as a thermistor that senses the temperature of the inner pot 4 via the heat receiving plate 14, and a heat-insulating heat-resistant tube 1
8 is protected.

Reference numeral 19 denotes an insulating plate such as a flat mica plate, which has holes 20 and 20 at appropriate locations through which both ends of the heat-resistant tube 18 can be inserted, and the insulating plate 19 is inserted into the flange portion 4a of the heat receiving plate 14. The outer circumferential edge and the upper circumferential edge of the outer frame 15 are fitted together and fixed by caulking, and the heat-sensitive element 17 is connected to the heat-receiving plate 14.
A shielded room S is formed in which the

The vertical width of this shielding chamber S is formed to be slightly narrower than the heat-resistant tube 18, and the heat-sensitive element 1 inside this heat-resistant tube 18
7 comes into contact with the back surface of the heat receiving plate 14.

The outer periphery of the support body 16 is attached to the inner wall of the outer frame 15 and has a sliding hole 21 formed approximately in the center thereof, and a pair of protrusions 22.22 are provided on the upper surface in close proximity to the sliding hole 21. is formed protrudingly.

An external spring 23 is interposed between the lower surface of the flange portion 14a and the upper surface of the mounting plate 10, and the heat sensitive body case 13 is always urged upward to protrude and retract from the through hole 9 of the bulged portion 8. I am free to do so.

A hanging piece 25 is formed at a suitable position at the lower end of the outer frame 15, passing through the through hole 12 and having a locking part 25a for preventing removal, so that the heat sensitive body case 13 can be attached to the outer spring 23.
It is regulated to prevent it from jumping out beyond a certain level.

Reference numeral 26 denotes an L-shaped connection terminal plate connected to a lead wire 27 connected to the heat-sensitive element 17, and is attached to the upper surface of the support body 16.

A movable contact 28 is electrically attached to the connection terminal plate 26, and has an L-shaped cross section.One end is attached to the connection terminal plate 26 as described above, and the other end is placed on the upper surface of the projection 22. It can be bent up and down.

Reference numeral 29 denotes an electrically insulating guide tube that is installed upright with a portion of its lower end inserted into the insertion hole 11, and the mounting plate 10 is attached to the lower circumferential side.
A flange portion 29a is placed on the top surface of the rice cooker, and a fixed contact 30 is inserted therein and is exposed on the top surface for indirectly electrically connecting the heating element 7 for rice cooking and a heating element for keeping heat to be described later.

Further, the guide tube 29 is inserted into the sliding hole 21 of the support body 16 so that the heat sensitive body case 13 can be slid up and down.

Reference numeral 31 denotes an internal spring interposed between the lower surface of the support body 16 and the flange portion 29a, which has a force that tends to return the guide tube 29 to its original position when it is tilted.

32 is a heat-retaining heating element wrapped around the outer periphery of the upper part of the outer pot 2;
Reference numeral 33 denotes an electrical equipment box having an electronic control circuit that can control the supply of electricity to both the heating elements 7 and 32 according to the temperature sensed by the heat-sensitive element 17.

Also, to explain the electric circuit shown in FIG. 4, the fixed contact 30
A series circuit of the open/close switch SW formed by the switch SW and the movable contact 28 and the heat sensitive element 17 is connected to the SC via the temperature detection circuit 35.
R#J! A first thyristor 40 that is connected to the SCR control electronic circuit 36 and that controls the energization to the rice cooking heating element 7 and a second thyristor that controls the energization to the heat retention heating element 32 on the output side of the SCR control electronic circuit 36. 41 is connected.

El and E2 are power supply terminals.

To explain the operation of such a configuration, as shown in FIG. 3, when the inner pot 4 is not housed in the outer pot 2, the heat sensitive body case 13 is protruded a certain distance by the external spring 23. The movable contact 28 integrally disposed on the heat-sensitive element case 13 and the fixed contact 30 disposed on the guide tube 29 are separated from each other, and the heat-sensitive element 17 is electrically disconnected from the heat-sensing element 17 by a structure not shown in the drawings. Even if an attempt is made to energize the inner pot, it will not be energized, thereby preventing empty cooking when the inner pot 4 is not stored.

Moreover, the open/close switch S composed of both contacts 28 and 30
Since W is housed in the heat sensitive element case 13 together with the heat sensitive element 17, these two can be compactly integrated and hermetically sealed.
) is protected by the heat sensitive body case 13 and is prevented from entering by dust and the like, so that there is no chance of damage to the bottom of the contact.

Further, when the inner pot 4 is housed in the outer pot 2 as shown in FIG. The case 13 is slid downward around the guide cylinder 29, and the movable contact 28 comes into contact with the fixed contact 30 to maintain the heat-sensitive element 17 in a conductive state, so that the rice-cooking heating element 7 and the heat-insulating The heating element 32 can be energized.

When power is supplied with the open/close switch SW closed, a signal is sent from the SCR control electronic circuit 36 to the gate of the first thyristor 40 until the rice cooking completion temperature reaches the preset rice heating element. 7 generates heat, the inner pot 4 is heated, and rice is cooked.

When the rice cooking progresses and the inner pot 4 reaches the rice cooking end temperature setting,
The heat-sensitive element 17 detects this temperature and inputs a signal to the SCR control electronic circuit 36 via the temperature detection circuit 35, and this input signal cuts off the gate signal to the first thyristor 40 for rice cooking. The heating of the heating element 7 is stopped to end the rice cooking.

On the other hand, when the heat-sensitive element 17 detects a decrease in the temperature of the inner pot 4 due to the stoppage of heat generation by the rice-cooking heating element 7, and detects a temperature suitable for keeping warm, the temperature detection circuit 35 and the SCR control electronic circuit 36 A gate signal is sent to the second thyristor 41 to enable electricity to be applied to the heat-retaining heating element 32 and to start the heat-retaining operation.

Further, since the heat-sensitive element 17 is in contact with the inner surface of the heat-receiving plate 14, the temperature of the inner pot 4 can be reliably detected through the heat-receiving plate 14. Since it is installed horizontally, it is possible to block the influence of heat from below the heating element 7 for rice cooking and perform stable heat-sensitive control.

Since the present invention is constructed as described above, even if power is supplied in parallel without storing it in the cooking device main body, the movable contact and the fixed contact are separated, so the heating element It is possible to prevent accidents such as fires due to dry cooking as the power is not turned on.

[Brief explanation of drawings]

Figure 1 is a cutaway side view of the main parts of a jar rice cooker equipped with the safety device of the present invention, Figure 2 is an enlarged cross-sectional view of the main parts of Figure 1, Figure 3 is a cross-sectional view of the same when the pot is removed, Figure 4 is an electrical circuit diagram in which the safety device of the present invention can be used. 4... Pot, 13... Heat sensitive body case, 2
3... Spring, 28... Movable contact, 30... Fixed contact.

Claims (1)

[Scope of utility model registration request] A heat sensitive body case which is placed in elastic contact with the bottom surface of a pot which is freely stored in the cooking device main body by the action of a spring; and a heat sensitive body case which is erected at the inner bottom of the cooking device body and allows the heat sensitive body case to be moved up and down. It consists of a guide cylinder, a fixed contact attached to the guide cylinder, and a movable contact disposed inside the heat sensitive body case and capable of coming into contact with and separating from the fixed contact, and when the pan is not stored, the spring A safety device for a cooking appliance, characterized in that the heat sensitive body case is moved upward to separate both the contacts.