JPH02286109A - Electric hot plate - Google Patents

Abstract

PURPOSE:To speedily and always exactly decide it without fail whether connecting between a connector and a connector receiver is suitable or not by detecting a temperature in the printed wiring of a PC plate, which generates heat in correspondence to electrification to a heater, by a temperature detector. CONSTITUTION:According to the set of an input device 19, for example, both relays 25a and 25b are opened, heaters 7 and 8 are electrified and a cooking plate 3 is heated. On the other hand, in correspondence to the start of the electrification to the heaters 7 and 8, a printed wiring (a) generates the heat by the electric resistance of the printed wiring itself. The thermal capacity of this printed wiring (a) is extremely small and the temperature rises up speedily and reaches a fixed temperature about within 30 seconds. The temperature of this printed wiring (a) is detected by a temperature detector 26. In a control circuit 16, a set temperature T0 set in advance is compared with a temperature T1 of the printed wiring (a) after the lapse of a prescribed time t1 since the input is started. By this comparison it is decided that presence or absence of the electrification to the heaters 7 and 8, namely, the propriety of the connection between a connector 11 and a connector receiver 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention 1 (Field of Industrial Application) This invention relates to an electric hot plate used for cooking meat, vegetables, etc.

(Prior Art) This type of electric hot plate includes a cooking plate and a storage frame that removably stores the cooking plate. Each has a built-in PC board that makes the circuit white. The cooking plate is provided with a connector that is provided with a terminal that conducts to the heater, and the storage frame is provided with a connector receiver that is provided with a terminal that is electrically connected to the PC board. When the cooking plate is housed in the storage frame, the connector connects to the connector receiver, thereby supplying power to the heater through the PC board.

However, if the connection between the connector and the connector receiver is incomplete, a situation may occur in which the heater of the cooking plate is not energized even if the control circuit is functioning normally. Even though a temperature detection element was installed to detect the temperature and the power switch was turned on, the cooking plate's I! If the A degree does not rise, it is determined that the connection between the connector and the connector receiver is incomplete and an alarm is issued.

(Problem to be Solved by the Invention) However, the cooking plate has a large heat capacity, and therefore even when the heater is actually energized, the gradient of temperature rise of the cooking plate after energization is small, and therefore there is a delay in temperature detection by the temperature detection element. This causes a problem in that it is not possible to quickly determine whether or not the connection between the connector and the connector receiver is appropriate. In addition, if you use a cooking plate and once remove the cooking plate from the storage frame and then store it again in the storage frame, the temperature of the cooking plate has already risen above a certain level. Even if the connection between the connector and the connector receiver is incomplete when the connector is re-stored, the temperature detection element will detect the temperature of the cooking plate and incorrectly judge that the connection is correct. be.

This invention was made in response to these points, and its purpose is to provide an electric hot plate that can quickly and always accurately determine whether or not the connection between a connector and a connector receiver is appropriate. It's about doing.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a cooking plate having a heater and a connector that conducts to the heater, and a storage frame for storing the cooking plate in a free space. a connector receiver provided on the storage frame and connected to the connector in accordance with the operation of storing the cooking plate in the storage frame; and a control provided on the storage frame for controlling energization of the heater. a PC board having a circuit and supplying power from the control circuit to the heater through the connector receiver and the connector, and detecting the temperature of printed wiring in a portion of the PC board that supplies power to the heater; An element is provided, and whether or not the heater is energized is determined based on the temperature of the printed wiring detected by the temperature detection element.

(Function) The printed wiring that supplies power to the heater generates heat due to its own electrical resistance when the connector on the cooking plate and the connector receiver on the storage frame are properly connected and current flows through the heater. If the connection between the connector on the cooking plate and the connector receiver on the storage frame is incomplete, no current will flow and no heat will be generated. When this printed wiring generates heat, its temperature rises quickly because its heat capacity is small.

In this invention, the temperature of the printed wiring, which increases rapidly in response to energization of the heater, is detected by the temperature detection element, and based on this detected temperature, it is determined whether or not the heater is energized, that is, the relationship between the connector and the connector receiver. The suitability of the connection is determined, and therefore the determination is made quickly and accurately.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

Fig. 2 shows the external appearance of the electric hot plate, in which numeral 1 is a storage frame body, a storage recess 2 is formed in this storage frame 1, and a cooking plate 3 is removably stored in this storage recess 2. be. At the inner bottom of the storage recess 2, a temperature sensor 4 is provided at the center, and a hook receiver 5 is provided at the corner at one end.

The cooking plate 3 is formed into a dish shape by die-casting aluminum, for example, and has a heater 7 at its bottom as shown in FIG.
8 is injected. At one end of the outer bottom of this cooking plate 3, there is a hook 9 that can be freely engaged with and detached from the hook receiver 5, and at the other end there are terminals 10a, 10 that are electrically connected to the heater 7.
Connectors 11 having connectors b and 10e are provided, respectively.

An operating section 14 is provided at the end of the storage frame 1, and a temporary PC 15 is installed inside this operating section 14.
Regarding the O circuit configuration, as shown in Figure 1, P
A control circuit 16 including a CCl2O microcomputer is provided,
A power supply 17 is connected to this control circuit 16 via a temperature fuse 18 . Further, in this control circuit 16, the temperature sensor 4, an input device 19 such as a switch, a display device 20 such as a lamp, and a connector receiver 21 are connected to a PC.
board] 5 through printed wiring (copper foil), and the input device 19 and display device 20 are arranged on the upper surface of the operation section 14. The connector receiver 21 has terminals 10a, 10b, which are provided on the connector 11 of the cooking plate 3.
It has a plurality of terminals 22a, 22b, 22C corresponding to the terminals 10a, 22b, 22C corresponding to the terminals 10a, 10b, 10c, and the connector 11 is connected to the connector receiver 21 in response to the operation of storing the cooking plate 3 in the housing section 2, and the terminals 10a, 10b, 10c correspond to each other. 10
c is electrically connected to 22a, 22b, and 22C. The terminals 22a, 22b and the control circuit 1
Relays 25a each controlled by the control circuit 16 are located in the middle of the printed wiring connecting the 6 and 6.

25b is provided. Note that when the cooking plate 3 is stored in the storage recess 2, the hook 9 is attached to the hook receiver C flap 5.
This engaged state is held by a locking mechanism (not shown), thereby fixing the cooking plate 3 to the storage frame 1.

In this state, the power source 17 is connected to both or one of the heaters 7.8 of the cooking plate 3 through PCCl2O printed wiring, depending on the input settings for the human power device 19.
is supplied.

For PCCl2O, a temperature detection element 26 is provided so as to cover the middle of the printed wiring a that supplies the power supply 17 to the heater 7.8, and this temperature detection element 26 is
f 1311 circuit 16.

Next, we will discuss the effect.

By setting the operation for input bag ri 119, for example, both relays 25a and 25t+ are closed, heater 7.8 is energized, these heaters 7.8 generate heat, and cooking plate 3 is heated. Here, the cooking plate 3 has a large heat capacity, and therefore, as shown by curve A in FIG. 4, the gradient of its temperature rise is small, and the set temperature is reached after about 5 minutes.

When the set temperature is reached, it is sensed by the temperature sensor 4, and relays 25a and 25b are opened and closed via the control circuit 16 in response to this sensing, and this opening and closing causes the cooking plate 3 to reach the set temperature. is maintained.

On the other hand, in response to the start of energization to the heater 7.8, the printed wiring a generates heat due to its own electrical resistance. The heat capacity of this printed wiring a is extremely small, so
As shown by the curve, the temperature of this printed wiring a rises quickly and reaches a certain temperature in about 30 seconds. Then, the temperature of this printed wiring a is detected by the temperature detection element 26, and based on this detection, the control circuit 16 sets the preset temperature To and the predetermined time t1 has elapsed since the start of the human power by the human power device 19. The temperature T1 of the printed wiring a at this point in time is compared, and in this comparison, the temperature of the heater 7.8
It is determined whether the connector 11 and the connector receiver 21 are properly connected. That is, simultaneously with an input operation on the input device 19, a timer built into the control circuit 16 starts, and 1. When the time elapses, the temperature T, and T. are compared, and T is compared with T. If it is higher than , it means that current is flowing through the heater 7.8, and therefore it is determined that the connection between the connector 11 and the connector receiver 21 is proper. On the other hand, TI is T. If the current is lower than , it means that no current is flowing through the heater 7.8, so it is determined that the connection between the connector 11 and the connector receiver 21 is incomplete, and this is displayed on the display device 20. be exposed. Note that even if the heater 7.8 is disconnected, it is detected and displayed in the same way.

In this way, the temperature of the printed wiring a is detected by the temperature detection element 26, and based on this detected temperature, the suitability of the connection between the connector 11 and the connector receiver 21 is determined.
As mentioned above, when the heater 7.8 is energized, the temperature of the printed wiring a rises quickly, and therefore, the suitability of the heating can be quickly determined. In addition, since the printed wiring a has a small heat capacity, the temperature quickly drops to almost room temperature when the power to the heater 7.8 is cut off. When the cooking plate 3 is then stored in the storage frame 1 and continued to be used while the cooking plate 3 remains at a high temperature, the connection between the connector 11 and the connector receiver 21 becomes incomplete. Even in such cases,
Since the temperature of the printed wiring a has returned to approximately room temperature, the suitability of the connection can be accurately determined without error. Furthermore, in terms of structure, since the temperature detection element 26 may be provided on the printed wiring a provided on the PC board 15, there is an advantage that the processing is easy and the structure can be constructed at low cost.

[Effects of the Invention] As explained above, according to the present invention, the temperature detection element detects the temperature of the printed wiring on the PC board, which generates heat when the heater is energized, and connects the connector of the cooking plate and the storage frame. Since the suitability of the connection with the connector receiver is determined, this determination can be made quickly and accurately.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a circuit diagram, Fig. 2 is a perspective view of an electric hot plate, Fig. 3 is a plan view showing the arrangement of heaters, and Fig. 4 is a diagram of a cooking plate and FIG. 3 is a graph diagram showing a temperature increase state of printed wiring. 1... Storage frame body, 3... Cooking plate, 7.8...
・Heater, 11...Connector, 15...PC board, 1
6... Control circuit, 17... Power supply, 21... Connector receiver, 26... Temperature detection element, a... Printed wiring.

Claims (1)

[Claims] A cooking plate having a heater and a connector electrically connected to the heater, a storage frame for removably storing the cooking plate, and a storage frame provided on the storage frame so that the cooking plate can be stored in the storage frame. Accordingly, a PC board includes a connector receiver connected to the connector, and a control circuit provided in the storage frame for controlling power supply to the heater, and supplies power from the control circuit to the heater through the connector receiver and the connector. comprising: the PC;
A temperature detection element is provided for detecting the temperature of printed wiring in a portion of the board that supplies power to the heater, and it is determined whether or not the heater is energized based on the temperature of the printed wiring detected by the temperature detection element. Electric hot plate.