JPH0248747Y2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> The present invention relates to a weight detection device for a heating cooker having a turntable, such as a microwave oven, and particularly to a weight detection device for measuring the weight of an object placed on a turntable. This invention relates to a liquid inflow prevention structure.

<Prior Art> Some recent microwave ovens are capable of measuring the weight of objects placed on the turntable by providing a weight detection device in the turntable mechanism within the heating chamber. This is because the food is heated and cooked according to the weight measured during automatic cooking, so when food is placed on the turntable, the weight is automatically measured.

However, if liquid such as water or coffee spilled into the heating chamber spills onto the turntable support shaft, the liquid will flow along the turntable support shaft and into the bearings and charging parts that make up the weight detection device, making accurate weight measurement impossible. However, there was a drawback that the desired automatic cooking could not be performed.

<Purpose> The present invention was developed in view of the above-mentioned drawbacks, and it captures the weight of the object placed on the turntable in the heating chamber as the amount of displacement in the thrust direction of the turntable support shaft, and calculates the amount of displacement in the thrust direction. In a weight detection device for a cooking device, which converts a dimensional change into a capacitance change between the electrode plates disposed below the turntable support shaft, and detects the capacitance change to detect the weight, By disposing a drainage member on the turntable support shaft to prevent liquids such as water, coffee, milk, etc. spilled into the heating chamber from flowing through the turntable support shaft and reaching the bearing section and the electrode plate, heating can be achieved. It is an object of the present invention to enable accurate weight detection even if a liquid such as water, coffee, milk, etc. spilled into a room hangs on the turntable support shaft.

<Example> Hereinafter, an example of the weight detection device for a cooking device of the present invention will be described based on the drawings.

FIG. 1 is a schematic vertical cross-sectional view of the weight detection device for a heating cooker according to the present invention. In FIG. It is a circular plate placed on top of the plate. These are built into the exterior body along with the components of the microwave oven, such as a magnetron, a heater, and a cooling fan (none of which are shown). Reference numeral 4 denotes a turntable support shaft, which is fixed below the center of the turntable holder 3 and extends below the heating chamber 2 through an opening 5 provided at the bottom of the heating chamber 2 .
The turntable support shaft 4 is rotatably supported by an upper bearing 6, a lower bearing 7, and a ball 8 at the lower end of the shaft, and a gear 9 fixed to the turntable support shaft 4 meshes with a drive gear 11 of a motor 10 to generate heat. rotates at times. The upper bearing 6 is fixed to an upper support plate 12, and the lower bearing 7, together with the motor 10, is fixed to a lower support plate 13, which is formed into a substantially U-shape, with screws 14, 14, respectively.

Reference numerals 15 and 15 are leaf springs, and spring fixing members 16 and 17 are sandwiched between the ends of the leaf springs from above and below, respectively. One spring fixing member 16 is fixed to a fixed electrode attachment plate 18 firmly attached to the bottom wall of the heating chamber 2, and the other spring fixing member 17 is attached to the upper support plate 12 and the support plate 13. is fixed thereto, and an L-shaped movable electrode attachment plate 19 is attached.

Therefore, the movable electrode mounting plate 19 uses the fixed electrode mounting plate 18 side as a fulcrum by the two leaf springs 15, 15, and is moved in proportion to the load applied to the turntable support shaft 4 based on the principle of the Roberval mechanism. Move up and down.

20 is an insulating material 2 at the lower end of the fixed electrode mounting plate 18.
2 with a fixed electrode plate mounted horizontally through 2
A movable electrode plate 1 is attached to the lower end of the movable electrode attachment plate 19 with an insulating material 22 in between, facing the fixed electrode plate 20 and below the fixed electrode plate 20.

Reference numeral 23 denotes a disc-shaped drainage member located above the upper bearing 6 and disposed on the turntable support shaft 4. As shown in FIG. The space between the shaft 4 and the shaft 4 is sealed so that the liquid flowing down the shaft 4 is completely blocked at this part.

The shape of the upper support plate 12 is designed to receive the liquid falling from around the draining member 23 so that it does not touch the fixed electrode plate 20 or the movable electrode plate 21, and to guide and discharge the liquid in a convenient direction. It is shaped like a dust pan as shown in Figure 3. By doing so, the size of the upper support plate 12 does not have to be large enough to completely cover the electrode plates 20 and 21, and it is possible to reliably prevent liquid from splashing onto the electrode plates 20 and 21. can do. In addition, 2
5 and 25 are lead wires connected to the electrode plates 20 and 21, and their free ends are connected to an oscillation circuit board (not shown).

Next, the operation of the above-mentioned capacitive displacement type weight detection device will be explained. When food is placed on the turntable 1, the leaf springs 15, 15 are bent under the weight of the food, and the movable electrode attachment plate 19 moves downward. Then, the movable electrode plate 21 moves downward, and the dimension between the fixed electrode plate 20 and the movable electrode plate 21 increases, and the electrode plate 2
The capacitance C between 0 and 21 becomes small based on the relationship [C=εS/d (S: electrode plate facing area, d: electrode plate size, ε: relative dielectric constant)]. The capacitance is converted into a frequency by an oscillation circuit and extracted as a frequency corresponding to the weight.

The present invention has a simple structure as described above, so that even if the user accidentally spills liquid such as water, coffee, or milk into the heating chamber 2 and the liquid flows down the turntable support shaft 4, the liquid will not be able to reach the bearing. 6 and 7 and the electrode plates 20 and 21, the same weight detection performance is maintained without any adverse effect on the weight detection mechanism. Note that the shape, size, location, mounting structure, etc. of the draining member 23 are not limited to the embodiments described above and illustrated, and the draining member 23 is formed of an elastic material such as rubber and press-fitted into the turntable shaft 4. It can be anything.

<Effects> The weight detection device for a heating cooker of the present invention is such that even if liquid such as water, coffee, or milk spills into the heating chamber and flows down the turntable support shaft, this liquid will be able to connect to the bottom of the heating chamber and the turntable. Since the liquid passes between the turntable support shaft and the draining part and is prevented from touching the electrode plate by the support plate, the liquid adheres between the turntable support shaft and the bottom of the heating chamber, and as a result of cooking, this liquid The liquid does not solidify and become a resistance to the displacement of the turntable support shaft in the thrust direction, and the solidification of this liquid does not affect the weight detection, making it possible to accurately detect the weight of the heated object. , liquid can be prevented from splashing onto the electrode plate.

[Brief explanation of the drawing]

Fig. 1 is a schematic vertical cross-sectional view of the weight detection device for a heating cooker according to the present invention, Fig. 2 is an external perspective view of the draining member of the present invention attached to a turntable support shaft, and Fig. 3 is a schematic diagram of the weight detecting device according to the present invention. It is an external perspective view of the upper support plate concerning this. Code, 1: turntable, 2: heating chamber, 4:
Turntable support shaft, 6: Upper bearing, 7: Lower bearing, 12: Upper support plate, 20: Fixed electrode plate, 21:
Movable electrode plate, 23: draining member.

Claims (1)

[Scope of utility model registration request] A turntable is provided in the heating chamber, a turntable support shaft is fixed below the center of the turntable, and the turntable support shaft is passed through with a gap between it and an opening provided at the bottom of the heating chamber. The weight of the heated object extended to the lower outside of the heating chamber and placed on the turntable is captured as the amount of displacement in the thrust direction of the turntable support shaft, and the amount of displacement in the thrust direction is determined as the amount of displacement in the thrust direction of the turntable support shaft. In a weight detection device for a heating cooker that converts a dimensional displacement between electrode plates disposed below into a capacitance change and detects the capacitance change to detect weight, the turntable support shaft described above is used. A disc-shaped draining portion is provided at a distance from the outside of the bottom surface of the heating chamber to allow liquids such as water, coffee, milk, etc. that have passed along the turntable support shaft to fall to the surrounding area, and below the draining portion. The drain section, which moves in conjunction with the displacement of the turntable support shaft in the thrust direction, is spaced apart so as not to impede the movement in the thrust direction, so that the liquid falling from around the drain section does not touch the electrode plate. A weight detection device for a heating cooker, characterized in that a support plate is provided to receive and discharge the weight.