JPH0789988B2 - Automatic rice cooker - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an automatic rice cooker used in general households, and more specifically, it is characterized by means for detecting the weight of an object to be cooked.

2. Description of the Related Art The configuration of a conventionally known automatic rice cooker of this type will be described with reference to FIG. In FIG. 5, reference numeral 1 is a bottomed cylindrical pot for storing rice to be cooked and water, and 2 is a protective frame for protecting the pot 1 while having a heating element 2a for heating the pot 1. Reference numeral 3 denotes a rice cooker main body (hereinafter simply referred to as a main body) that houses the pan 1 and the protective frame 2, and is provided so as to be slidable in the vertical direction with respect to the bottom plate 3a. Reference numeral 4 denotes a coil spring arranged between the bottom of the protective frame 2 and the upper surface of the bottom plate 3a, which expands and contracts under the weight of the pot 1 and the protective frame 2. Reference numeral 5 denotes an arm fixed to the bottom plate 3a, which is connected to a lever 5b of a slide type variable resistor 5a provided on the main body 3.

With the above configuration, put rice and water in the pot 1 and put in the protective frame 2
If set inside, the coil spring 4 receives this weight and is displaced, and the main body 3 moves downward. By detecting this moving amount with the variable resistor 5a, the amount of rice and water put in the pot 1 can be detected.

Problems to be Solved by the Invention However, the automatic rice cooker having the above configuration has a problem that the accuracy of weight detection is low. That is, when the side wall of the main body 3 is in contact with a structure such as a wall, the movement of the main body 3 is hindered and the weight cannot be accurately detected. In addition, the parts involved in weight detection are the coil spring 4,
Since the main body 3, the arm 5, and the variable resistor 5a are large, the total sum of the variations of the individual parts is large, the weight cannot be accurately detected, and the mechanical loss between the parts acts on the coil spring 4 as a moment. Therefore, the main body 3 tilts, the frictional force increases, and the accuracy of weight detection decreases.

The present invention solves the problem of such a conventional configuration, and an object thereof is to provide an automatic rice cooker capable of accurate and highly accurate weight detection.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention has a bottomed cylindrical pan for accommodating an object to be heated, and a bottomed cylinder for protecting the pan while having a heating element for heating the pan. -Shaped protection frame, a support rod provided on the outer bottom of the protection frame that receives the weight of the pot, a weight detection element with which the support rod abuts, a rice cooker body having the weight detection element, and the protection frame. The automatic rice cooker includes a provided first magnet and a second magnet that is magnetized in a direction to repel the first magnet and that regulates the position of the first magnet.

Operation The present invention can transmit the weight of the pan directly to the weight detection element through the support rod, and is not affected even if a structure such as a wall comes into contact with the side surface of the rice cooker main body, and The expected rotational movement of the protective frame during rice cooking can be regulated in a non-contact state, and the weight detection accuracy can be further enhanced.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. The members having the same functions as those of the conventional example described in FIG. 5 are given the same numbers. In the figure, reference numeral 2 is a bottomed cylindrical protective frame having a heating element 2a and a heat sensing element 2b on the inner bottom and protecting the pot 1. The support rod 6 is fixed by a method such as press fitting. Reference numeral 7 denotes a rice cooker main body, a vertical slide type bearing 7a supporting the support rod 6, a main body portion 7c having an upper frame 7b, and a bottom plate.
It consists of 7d. Reference numeral 8 is a weight detection element provided on the bottom plate 7d. The support rod 6 receives the weight of the pot 1 and transmits the weight to the weight detection element 6 in points.

Further, the weight detecting element 8 uses a capacitance type piezoelectric sensor in this embodiment, and has a structure as shown in FIG. In FIG. 3, both 8a and 8b are ceramics, and electrodes 8c and 8d are provided on the surface. Reference numeral 8e is a spacer made of a material having elasticity. With this configuration, when pressure is applied to the upper ceramic 8a, the spacer 8e is loosened, the distance between the electrodes 8c and 8d is reduced, and the capacitance is increased.

Reference numeral 9 is a lid, and 10 is wiring for the heating element 2a and the heat sensing element 2b. Reference numeral 11 denotes a first magnet for restricting the position of the protective frame 2, which is attached to the bottom surface of the protective frame 2 using a support tool. Reference numerals 12a and 12b denote second magnets that are magnetized in a direction that repels the first magnet 11, respectively.
Are installed so that they can be entered without touching. The support 13 is fixed to the bottom plate 7d by a method such as screwing, and the ends on the magnet 12a and 12b side are the main body 7c.
Looking through to the magnet 11 side through the hole 7e at the bottom of the.

Next, the operation of the present embodiment having the above configuration will be described.
When the pot 1 containing the rice to be cooked and water is set in the protective frame 2, the support rod 6 provided at the center of the bottom surface of the protective frame 2 corresponds to the weight of the pot 1 and the weight detection element. Press 8. This increases the capacitance of the weight detection element 8. That is, the capacitance of the weight detection element 8 changes according to the weight of the pan 1. By reading the value of this capacitance, the amount of rice and water in the pot 1 can be known. At this time, the outer peripheral flange 2c of the protective frame 2 and the upper frame 7b of the rice cooker body 7 are in a positional relationship where they do not come into contact with each other. Even if a structure such as a wall is in contact with the side surface of the rice cooker body 7, the weight can be detected without any trouble. In addition, since the displacement of the support rod 6 is directly received by the weight detection element 8, the variation in parts is smaller than that in the conventional method which requires many parts such as a coil spring, a main body, an arm, and a slide type variable resistor. The influence of the weight is extremely small, and the weight loss can be detected with high accuracy without mechanical loss as in the conventional case.

Here, let us consider the influence of convection motion of the food to be cooked during the rice cooking process. When the pan 1 vibrates due to convective motion of the food to be cooked during the rice cooking process, this vibration is transmitted to the protective frame 2 and the protective frame 2 rotates. As a result, the position of the wiring 10 also changes significantly, and there is a case where it touches the hole edge of the main body 7c. In this case, the weight cannot be accurately detected due to the frictional force due to the contact with the hole edge portion of the main body portion 7c of the wiring 10.

In order to avoid such a situation, it is conceivable to regulate the movement of the protective frame 2. For example, the protective frame 2 is fixed to the main body 7 by providing an uneven portion having a fitting relationship with the protective frame 2. But this way,
A frictional force is also generated in the uneven portion, and similarly, accurate weight detection cannot be performed.

Therefore, in the present embodiment, the first magnet 11 and the second magnets 12a and 12b magnetized in a direction to repel the first magnet 11 are provided,
Even when rice is being cooked, the first magnet 11 is fixed so as not to come into contact with the second magnets 12a and 12b so as to be located at an intermediate position. Therefore, when the weight is detected, the position of the protective frame 2 can be regulated without generating any frictional force. Therefore, the support rod 6 always receives the weight of the pan 1 and transmits this pressure to the weight detection element 8 at a point. As a result, highly accurate weight detection can be performed.

In the present embodiment, the second magnets 12a and 12b are composed of two magnets, but the second magnet may be formed in a ring shape and the position of the first magnet 11 may be regulated at the center thereof. Is.

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, accurate weight detection can be performed even when a structure such as a wall is in contact with the side surface of the rice cooker main body, and it is also involved in weight detection. Since the number of parts to be used is small, it is less affected by variations in individual parts, there is no mechanical loss, and the position of the protective frame is regulated using a magnet, so automatic rice cooking with high accuracy weight detection is possible. Can be provided.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of an automatic rice cooker of the present invention, FIG. 2 is a cutaway front view showing the same assembled state, and FIG. 3 shows a structure of a weight detection element in the rice cooker. FIG. 4 is a longitudinal sectional view, FIG. 4 is an exploded perspective view showing the same main portion, and FIG. 5 is a longitudinal sectional view showing the structure of a conventional automatic rice cooker. 1 ... pan, 2 ... protection frame, 2a ... heating element, 6 ... support rod, 7 ... rice cooker main body, 7a ... bearing, 8 ... weight detection element, 11 ... first magnet, 12a, 12b ... Second magnet.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yukio Hayashida 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Seiichi Taniguchi 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 56) References JP-A-62-121018 (JP, A)

Claims (1)

[Claims] Claim: What is claimed is: 1. A bottomed cylindrical pan for containing an object to be heated, a bottomed cylindrical protection frame for protecting the pan while having a heating element for heating the pan, and a protection for receiving the weight of the pan. The support rod provided on the outer bottom portion of the frame, the weight detection element with which the support rod abuts, the rice cooker main body having the weight detection element, the first magnet provided in the protection frame, and the first magnet. An automatic rice cooker including a second magnet that is magnetized in a repulsive direction and regulates the position of the first magnet.