JP2012202922A - Weight detection apparatus and heating cooker having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weight detection apparatus or the like capable of preventing an excess load from being applied to a weight sensor even when mistakenly dropped.SOLUTION: The weight detection apparatus includes: a body 1 for installing thereon an object 6 requiring measurement of weight; a weight sensor 7 which is provided on the upper surface of the bottom of the body 1 and detects the magnitude of the downward load in accordance with the push-in amount from upward; and a measurement leg 11 which has a contact part 11a for pushing in the weight sensor 7 from upward and a projection 11b protruding downward from the bottom of the body 1, and which is provided on the body 1 movably in the vertical direction so that the amount of movement upward of the contact part 11a is increased in accordance with an increase in the weight of the object 6 installed on the body 1 when the projection 11b is pushed in above the body 1 by contact with the installation surface during installation of the body 1.

Description

  The present invention relates to a weight detection device and a cooking device including the same.

  The cooking device is provided with a weight detection device. The weight detection device is provided with a weight sensor. In the conventional weight detection device, if the weight of an object requiring weight measurement increases, the load applied to the weight sensor also increases. Based on this load change, the weight of the object is detected (for example, refer to Patent Document 1).

Japanese Unexamined Patent Publication No. 7-5020

  However, if the cooking device is accidentally dropped, an excessive load is applied to the weight sensor. In this case, the weight sensor can fail.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a weight detection device capable of preventing an excessive load from being applied to the weight sensor even when it is accidentally dropped. It is providing the cooking device provided with this.

  A weight detection device according to the present invention is provided on a main body for installing an object requiring weight measurement and an upper surface of a bottom portion of the main body, and detects a magnitude of a downward load according to an amount of pushing from above. A weight sensor; a contact portion that pushes the weight sensor from above; and a protrusion that protrudes downward from the bottom of the main body, and the protrusion protrudes above the main body by contact with an installation surface when the main body is installed. A measuring foot provided so as to be movable in the vertical direction with respect to the main body so that the amount of upward movement of the contact portion increases in accordance with an increase in the weight of an object placed on the main body when pushed. , With.

  According to the present invention, it is possible to prevent an excessive load from being applied to the weight sensor even when it is accidentally dropped.

It is the figure which looked at the inside of the heating cooker provided with the weight detection apparatus in Embodiment 1 of this invention from the side. It is a principal part detail drawing of FIG. It is a perspective view of the measurement leg | foot of the weight detection apparatus in Embodiment 1 of this invention. It is a perspective view of the measurement leg | foot of the weight detection apparatus in Embodiment 1 of this invention. It is a figure for demonstrating the characteristic of the weight detection apparatus in Embodiment 1 of this invention. It is a flowchart for demonstrating the utilization procedure of the heating cooker provided with the weight detection apparatus in Embodiment 1 of this invention. FIG. 3 is a view corresponding to FIG. 2 in Embodiment 2 of the present invention. It is a perspective view of the measurement leg | foot of the weight detection apparatus in Embodiment 2 of this invention. It is a perspective view of the measurement leg | foot of the weight detection apparatus in Embodiment 2 of this invention. It is FIG. 2 equivalent figure in Embodiment 3 of this invention.

  A mode for carrying out the invention will be described with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

Embodiment 1
1 is a side view of the inside of a heating cooker provided with a weight detection device according to Embodiment 1 of the present invention. FIG. 2 is a detailed view of the main part of FIG.

  First, the outline of a heating cooker will be described with reference to FIG. In FIG. 1, 1 is a main body of a heating cooker. A heating means 2 such as an induction heating coil is provided in the heating cooker body 1. A conductive container 3 is provided immediately above the heating means 2. For example, when the heating cooker is an electric rice cooker, the conductive container 3 is an inner pot. A weight detector 4 is provided on one side of the bottom of the heating cooker body 1. A control determination circuit board 5 is provided in the vicinity of the weight detection device 4.

  In addition, the relationship of the magnitude | size of each structural member may differ from an actual thing. Further, a plurality of weight detection devices 4 may be provided. For example, the weight detection apparatus 4 may be provided in all the grounding parts of a heating cooker.

  In such a heating cooker, a heated object 6 such as rice or water is mounted in a conductive container 3. The weight of the object to be heated 6 is detected by the weight detection device 4. Based on the detection result of the weight detection device 4, the control determination circuit board 5 controls energization of the heating means 2.

  Next, the weight detection device 4 will be specifically described with reference to FIGS. 1 and 2. The weight detection device 4 includes a weight sensor 7, a measurement foot 8, a plate body 9, and a return spring 10.

  The weight sensor 7 includes a load cell. The weight sensor 7 has a function of detecting the magnitude of the downward load according to the amount of pressing from above.

  The measurement foot 8 includes a contact portion 8a and a protruding portion 8b. The contact portion 8a is disposed so as to contact the weight sensor 7 from above. The protrusion 8b is disposed so as to protrude downward from the bottom of the heating cooker body 1 through both sides of the weight sensor 7 from both sides of the contact portion 8a.

  The plate body 9 is made of a resin or sheet metal having sufficient rigidity with glass fibers. The plate body 9 is fixed to the heating cooker body 1 so as to cover the measurement foot 8 from above. The return spring 10 is a compression coil spring. The return spring 10 is disposed between the upper lower surface of the plate body 9 and the contact portion 8 a of the measurement foot 8. The return spring 10 urges the contact portion 8a of the measurement foot 8 to be pushed downward.

Next, the measurement foot 8 will be specifically described with reference to FIGS. 3 and 4.
3 and 4 are perspective views of the measurement legs of the weight detection device according to Embodiment 1 of the present invention.

  As shown in FIGS. 3 and 4, the measurement foot 8 has a substantially cylindrical shape. The upper part of the measurement foot 8 is closed. The upper part of the measurement foot 8 becomes the contact portion 8a. A protrusion is provided at the center of the lower surface of the contact portion 8a. The protrusion is formed in a conical shape that is pointed downward. The lower end of the protrusion comes into contact with the weight sensor 7. For this reason, the contact area of the protrusion with the weight sensor 7 is small. Thereby, the torsional distortion at the time of contact with the weight sensor 7 is suppressed. As a result, a decrease in the weight measurement accuracy of the weight sensor 7 is suppressed.

  A notch is formed on the side surface of the measurement foot 8. The side surface of the measurement foot 8 is divided by the notch. By this division, the protruding portion 8b is formed.

Next, the characteristics of the weight detection device 4 will be described with reference to FIG.
FIG. 5 is a diagram for explaining the characteristics of the weight detection apparatus according to Embodiment 1 of the present invention. The horizontal axis of FIG. 5 is the mass (kg) of the article 6 to be heated. The vertical axis in FIG. 5 represents the output voltage (mV) of the weight detection device 4.

  First, consider a case where the user is lifting the cooker body 1. In this case, the heating cooker body 1 is floating in the air. For this reason, the edge part of the protrusion part 8b of the measurement leg 8 is not contacting anywhere. In this case, the contact portion 8 a of the measurement foot 8 is pressed downward by the urging force of the return spring 10. This urging force is detected by the weight sensor 7. That is, the downward load applied to the weight sensor 7 is equal to the repulsive force of the return spring 10.

  Next, consider a case where the user has installed the heating cooker body 1. In this case, the end of the protrusion 8b of the measurement foot 8 is in contact with the installation surface. For this reason, the measurement foot 8 moves upward with respect to the heating cooker body 1 while pressing the return spring 10 upward. Thereafter, the measurement foot 8 stops at a position where the forces are balanced. As a result, the downward load applied to the weight sensor 7 is reduced in accordance with the weight of the heating cooker body 1 than when the heating cooker body 1 is lifted.

  Next, consider a case where the user puts the object to be heated 6 into the conductive container 3. In this case, the measurement foot 8 moves upward with respect to the heating cooker body 1 while compressing the return spring 10 upward according to the weight of the article 6 to be heated. Thereafter, the measurement foot 8 stops at a position where the forces are balanced. As a result, the downward load applied to the weight sensor 7 is reduced according to the weight of the object to be heated 6 than when the object to be heated 6 is not installed in the conductive container 3.

  Therefore, as shown in FIG. 5, the output voltage of the weight detection device 4 decreases as the weight increases corresponding to the mass of the object 6 to be heated. The weight of the object to be heated 6 is detected according to this output voltage.

  Next, the specification of the return spring 10 will be described. Consider the case where the grounding point of the heating cooker body 1 is four points and the weight detection devices 4 are provided at all four points. In this case, if the mass of the heating cooker body 1 is 6.5 kg and the maximum value of the mass of the article 6 to be heated is 2.5 kg, the maximum load P is 88.2N.

  At this time, the load applied to each measurement foot 8 is 22.05N. Therefore, when the maximum displacement δ in the vertical direction of each measuring foot 8 is set to about 5 mm, the spring constant k of the return spring 10 may be set to 22.05 N / 5 mm = 4.41 N / mm.

  Next, the specification of the weight sensor 7 will be described. When the maximum load P is 88.2N, each weight sensor 7 only needs to be able to detect up to 22.05N. Therefore, what is necessary is just to set the load operation | movement range of each weight sensor 7 to 0-22.5N.

  At this time, the weight change per unit heated object 6 is about 0.5 kg. For this reason, the amount of displacement of the return spring 10 is about 300 μm. Therefore, the displacement resolution of the weight sensor 7 may be set to 300 μm or less.

  When the maximum load P is 88.2 N, all of the maximum loads P can be applied to one measuring foot 8. At this time, the corresponding weight sensor 7 is loaded with a maximum load P of 88.2N. Therefore, the allowable weight of the weight sensor 7 may be set to a weight corresponding to 9 kg or more.

Next, the utilization procedure of an electric rice cooker is demonstrated as an example of the utilization method of a heating cooker using FIG.
FIG. 6 is a flowchart for explaining a procedure for using the heating cooker provided with the weight detection device according to Embodiment 1 of the present invention.

  First, in step S <b> 1, the user turns on the electric rice cooker without including the conductive container 3 and the object to be heated 6. Then, it progresses to step S2 and a user pushes the calibration button of an electric rice cooker.

  Then, it progresses to step S3 and an electric rice cooker memorize | stores the output value of the weight detection apparatus 4 as the calibration value A. FIG. Then, it progresses to step S4 and an electric rice cooker determines whether the calibration value A is in the range prescribed | regulated previously. Specifically, the threshold value of the calibration value A is set to the weight ± 10% of the electric rice cooker in a state where the conductive container 3 is not included. For example, when the mass of the present electric rice cooker not including the conductive container 3 is 6.5 kg, the calibration value A needs to satisfy a weight corresponding to 5.85 kg or more and 7.15 kg or less.

  If the calibration value A is within a pre-defined range, the process proceeds to step S5. In step S5, the electric rice cooker notifies the user that the calibration is completed by sound or display. Then, it progresses to step S6 and a user installs the container 3 which has the electroconductivity which mounted the to-be-heated material 6 in an electric rice cooker.

  Then, it progresses to step S7 and a user presses the rice cooking start button of an electric rice cooker. Then, it progresses to step S8 and an electric rice cooker memorize | stores the output value of the weight detection apparatus 4 as the measured value X. FIG. Then, it progresses to step S9 and an electric rice cooker deducts the weight corresponding to the calibration value A and the weight M of the container 3 which has preset electroconductivity from the weight corresponding to the measured value X. The weight Y is calculated.

  Then, it progresses to step S10 and an electric rice cooker determines whether the weight Y of the to-be-heated material 6 is in the range prescribed | regulated previously. Specifically, the threshold value of the weight Y of the article to be heated 6 is set to ± 20% of the upper and lower limits of the weight of the article to be heated 6 that can be taken by the electric rice cooker. For example, in the case of an electric rice cooker having a specification of 1 to 5 rice cookers, the weight Y of the heated object 6 can take a weight corresponding to 0.5 to 2.5 kg. In this case, the weight Y of the article to be heated 6 needs to be a weight corresponding to 0.4 kg or more and 3 kg or less.

  If the weight Y of the article 6 to be heated is within a predetermined range, the process proceeds to step S11. In step S11, the electric rice cooker notifies the user that the measurement has been completed by sound or display. Then, it progresses to step S12 and an electric rice cooker selects specific rice cooking control based on the weight Y of the to-be-heated material 6 and the rice cooking control table for every weight Y of the to-be-heated material 6 memorize | stored previously. Then, it progresses to step S13 and an electric rice cooker starts rice cooking operation | movement based on the selected rice cooking control.

  If the calibration value A is out of the pre-defined range in step S4, the process proceeds to step S14. In step S14, the electric rice cooker notifies the user of an error, urges the user to review the installation method and weight measurement conditions, and perform weight measurement again, and returns to step S2.

  On the other hand, if the weight Y of the article 6 to be heated is outside the range defined in advance in step S10, the process proceeds to step S15. In step S15, the electric rice cooker notifies the user of an error, urges the user to review the installation method of the article to be heated 6 and perform weight measurement again, and returns to step S5.

  Next, consider the case where the user accidentally drops the heating cooker body 1 using FIG. In this case, the projecting portion 8b of the measuring foot 8 receives an upward impact force when grounded. For this reason, the measurement foot 8 moves upward with respect to the heating cooker body 1 while compressing the return spring 10 upward according to the impact force.

  In this case, the downward load applied to the weight sensor 7 decreases as the impact force increases. In some cases, the contact portion 8 a of the measuring foot 8 is completely released from contact with the weight sensor 7. At this time, the load received by the weight sensor 7 is zero.

  According to Embodiment 1 demonstrated above, the downward load concerning the weight sensor 7 falls, so that the upward load concerning the measurement leg 8 is large. For this reason, even if it is a case where the heating cooker main body 1 is accidentally dropped, it can prevent that the excessive load more than tolerance is applied to the weight sensor 7. FIG. That is, failure of the weight sensor 7 is prevented. For this reason, the weight detection apparatus 4 maintains normal operation.

  Further, the protruding portion 8 b of the measuring foot 8 passes through both sides of the weight sensor 7 and protrudes downward from the bottom of the heating cooker body 1. For this reason, the support of the heating cooker by the measurement foot 8 can be stabilized.

  Moreover, heating conditions are controlled based on the detection result of the weight of the article 6 to be heated. For this reason, cooking suitable for the article 6 to be heated can be performed.

Embodiment 2
FIG. 7 is a view corresponding to FIG. 2 in Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to Embodiment 1 and an equivalent part, and description is abbreviate | omitted.

  As shown in FIG. 7, the measurement foot 11 of Embodiment 2 is formed like a cantilever. One side of the contact portion 11a of the measuring foot 11 is rotatably supported on one side surface of the plate body 9 by a horizontal rotation shaft 12. On the other side of the contact portion 11a of the measurement foot 11, a protruding portion 11b is formed. The protruding portion 11 b protrudes downward from the bottom of the heating cooker body 1 through the side of the weight sensor 7. The measuring foot 11 is biased by the return spring 10 from above the protruding portion 11b.

Next, the end of the protruding portion 11b of the measurement foot 11 will be described with reference to FIGS.
8 and 9 are perspective views of the measurement legs of the weight detection device according to Embodiment 2 of the present invention.

  As shown in FIGS. 8 and 9, the lower end of the protruding portion 11b of the measuring foot 11 is formed at a predetermined local rate. Thereby, whatever the contact angle between the protruding portion 11b of the measuring foot 11 and the installation surface of the heating cooker body 1 is, the contact area between the protruding portion 11b and the installation surface becomes small.

  According to the second embodiment described above, the measurement foot 11 is formed like a cantilever. As a result, the protruding portion 11b of the measuring foot 11 is only one. For this reason, the hole formed in the bottom part of the heating cooker main body 1 can be decreased rather than Embodiment 1. FIG.

Embodiment 3
10 is a view corresponding to FIG. 2 in Embodiment 3 of the present invention. In addition, the same code | symbol is attached | subjected to the part which is the same as that of Embodiment 2, or an equivalent, and description is abbreviate | omitted.

  As shown in FIG. 10, one side of the contact portion 13 a of the measurement foot 13 according to the third embodiment is fixed to the plate body 9. In the third embodiment, the contact portion 13a of the measurement foot 13 bends like a leaf spring to contact the weight sensor 7 from above.

  According to the third embodiment described above, the contact portion 13a of the measurement foot 13 is bent to contact the weight sensor 7 from above. For this reason, the return spring 10 can be made unnecessary.

DESCRIPTION OF SYMBOLS 1 Heating cooker body 2 Heating means 3 Conductive container 4 Weight detection device 5 Control determination circuit board 6 Object to be heated 7 Weight sensor 8 Measuring foot 8a Contact portion 8b Protruding portion 9 Plate body 10 Return spring 11 Measuring foot 11a Contact Part 11b Protruding part 12 Rotating shaft 13 Measuring foot 13a Contact part 13b Protruding part

Claims (5)

A body for installing objects that require weight measurement;
A weight sensor that is provided on the upper surface of the bottom of the main body and detects the magnitude of the downward load according to the amount of pushing from above,
A contact portion that pushes the weight sensor from above and a protrusion that protrudes downward from the bottom of the main body, and when the protrusion is pushed above the main body by contact with an installation surface when the main body is installed A measuring foot provided so as to be movable in the vertical direction with respect to the main body so that the amount of upward movement of the contact portion increases in accordance with an increase in the weight of an object installed on the main body,
A weight detection device comprising: A spring for biasing the measuring foot downward;
With
The contact portion pushes the weight sensor from above by the biasing force of the spring,
The weight detection device according to claim 1, wherein the protruding portion protrudes downward from the bottom portion of the main body through both sides of the weight sensor from both sides of the contact portion. A spring for biasing the measuring foot downward;
With
The contact portion pushes the weight sensor from above by the biasing force of the spring in a state where one side is rotatably supported by the main body,
2. The weight detection device according to claim 1, wherein the protruding portion protrudes downward from the bottom portion of the main body through the side of the weight sensor from the other side of the contact portion. The contact portion pushes the weight sensor from above by bending in a state where one side is fixed to the main body,
2. The weight detection device according to claim 1, wherein the protruding portion protrudes downward from the bottom portion of the main body through the side of the weight sensor from the other side of the contact portion.   A heating cooker that includes the weight detection device according to any one of claims 1 to 4, and that controls heating conditions based on a detection result of a weight of an object installed on the main body.

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