JP6832525B2 - Pressure cooker and pressure sensor unit - Google Patents

Description

The present invention relates to a pressure-type cooker that cooks cooked food by pressurizing the pressure in the pot to atmospheric pressure or higher, and more particularly to a pressure sensor unit used in the pressure-type cooker.

Conventionally, as this type of pressure cooker, for example, the pressure cooker described in Patent Document 1 is known. The pressure-type rice cooker of Patent Document 1 is configured to incorporate a pressure sensor for detecting the pressure in the pot in the lid.

JP-A-2003-339524

However, in the conventional pressure type cooker, since the steam generated in the pot is in direct contact with the pressure sensor, the pressure sensor may be damaged or deteriorated due to the moisture and temperature of the steam. In addition, steam may condense in the communication passage that communicates the inside of the pot and the pressure sensor, and the communication passage may be blocked by the condensed water. In this case, the pressure in the pot cannot be detected accurately. Therefore, in the conventional pressure type cooker, there is still room for improvement from the viewpoint of improving the pressure detection accuracy.

Therefore, an object of the present invention is to provide a pressure type cooker and a pressure sensor unit capable of improving the pressure detection accuracy in solving the above problems.

In order to achieve the above object, the pressure type cooker according to the present invention includes a pot and
A lid that opens and closes the upper opening of the pot,
A pressure sensor unit built into the lid and detecting the pressure inside the pan,
With
The pressure sensor unit is
A pressure sensor that detects pressure and
A communication passage that communicates the inside of the pot with the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. It has become.

Further, the pressure type cooker according to the present invention includes a pressure sensor for detecting pressure and a pressure sensor.
A communication passage that communicates the external space where steam is generated and the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. It has become.

According to the present invention, the pressure detection accuracy can be improved.

It is a schematic sectional view of the pressure type rice cooker which concerns on embodiment of this invention. It is sectional drawing which shows in the perspective view of the pressure type rice cooker of FIG. It is a partial notch side view of the pressure type rice cooker of FIG. It is a top view which shows the state which the part on the upper outer part member side of the outer lid is removed from the pressure type rice cooker of FIG. It is a perspective view which shows by disassembling a part part of FIG. It is an exploded perspective view of the pressure sensor unit from diagonally below. It is an exploded perspective view which looked at the pressure sensor unit from diagonally above. It is an assembly sectional view of a pressure sensor unit. It is sectional drawing which shows the state which elastically deformed the diaphragm member toward the pressure sensor side. It is sectional drawing which shows the state which elastically deformed the diaphragm member to the pot side. It is sectional drawing which shows the structure which provided so that the annular bending part of the diaphragm member protrudes to the pressure sensor side. It is sectional drawing which shows the modification of the diaphragm member.

According to the first aspect of the present invention, a pot and
A lid that opens and closes the upper opening of the pot,
A pressure sensor unit built into the lid and detecting the pressure inside the pan,
With
The pressure sensor unit is
A pressure sensor that detects pressure and
A communication passage that communicates the inside of the pot with the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. Provides a pressure cooker that has become.

According to the second aspect of the present invention, the diameter of the opening end on the pot side of the communication passage is larger than the diameter of the opening end on the pressure sensor side of the communication passage, and is larger than the diameter of the intermediate portion of the communication passage. Provided is the pressure cooker according to the first aspect, which is also small.

According to the third aspect of the present invention, the communication passage has a first reduced diameter portion whose diameter becomes smaller from the intermediate portion toward the opening end portion on the pressure sensor side on the pressure sensor side of the diaphragm member. And
The pressure type cooker according to the first or second aspect, wherein the shape of the first reduced diameter portion is substantially the same as the shape of the diaphragm member elastically deformed toward the first reduced diameter portion.

According to the fourth aspect of the present invention, the atmospheric pressure is P 0 , the pressure received by the diaphragm member when the diaphragm member is elastically deformed toward the first reduced diameter portion is P1, and the diaphragm member and the said diaphragm member are described. When the volume of the space surrounded by the first reduced diameter portion is Vk and the volume of the space communicating the first reduced diameter portion and the opening end portion of the communication path on the pressure sensor side is Va, P0 (Va). The pressure type cooker according to a third aspect, which satisfies the relationship of + Vk) / P1 · Va> 1, is provided.

According to the fifth aspect of the present invention, the diaphragm member has an annular flexible portion protruding in the thickness direction of the diaphragm member in an inelastically deformed state, according to any one of the first to third aspects. Provides a pressure cooker.

According to the sixth aspect of the present invention, the pressure type cooker according to the fifth aspect, wherein the annular flexible portion projects toward the pan side.

According to the seventh aspect of the present invention, there is provided the pressure type cooker according to the fifth or sixth aspect, wherein the inner diameter of the annular flexible portion is equal to or larger than the diameter of the opening end portion on the pot side of the communication passage. ..

According to an eighth aspect of the present invention, the communication passage has a second reduced diameter portion on the pot side of the diaphragm member, the diameter of which decreases from the intermediate portion toward the opening end on the pot side.
The pressure according to any one of the first to seventh aspects, wherein the second diameter-reduced portion is formed in a tapered shape so as not to come into contact with the diaphragm member elastically deformed toward the second diameter-reduced portion. Provides a formula cooker.

According to the ninth aspect of the present invention, a pressure sensor for detecting pressure and a pressure sensor
A communication passage that communicates the external space where steam is generated and the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. The pressure sensor unit is provided.

According to the tenth aspect of the present invention, the diameter of the opening end portion on the external space side of the communication passage is larger than the diameter of the opening end portion on the pressure sensor side of the communication passage, and the diameter of the intermediate portion of the communication passage. The pressure sensor unit according to the ninth aspect, which is smaller than the above, is provided.

According to the eleventh aspect of the present invention, the communication passage has a first reduced diameter portion whose diameter becomes smaller from the intermediate portion toward the opening end portion on the pressure sensor side on the pressure sensor side of the diaphragm member. And
The pressure sensor unit according to the ninth or tenth aspect, wherein the shape of the first reduced diameter portion is substantially the same as the shape of the diaphragm member elastically deformed toward the first reduced diameter portion.

According to the twelfth aspect of the present invention, the atmospheric pressure and P 0, the pressure to which the diaphragm member is subjected when the diaphragm member is elastically deformed toward the first reduced diameter portion and P1, the said diaphragm member When the volume of the space surrounded by the first reduced diameter portion is Vk and the volume of the space communicating the opening of the first reduced diameter portion and the opening end portion of the communication passage on the pressure sensor side is Va. The pressure sensor unit according to the eleventh aspect, which satisfies the relationship of P0 (Va + Vk) / P1 · Va> 1, is provided.

According to the thirteenth aspect of the present invention, the diaphragm member has an annular flexed portion protruding in the thickness direction of the diaphragm member in an inelastically deformed state, according to any one of the ninth to twelfth aspects. Pressure sensor unit is provided.

According to the 14th aspect of the present invention, the pressure sensor unit according to the 13th aspect, wherein the annular flexible portion projects toward the external space side.

According to the fifteenth aspect of the present invention, there is provided the pressure sensor unit according to the thirteenth or fourteenth aspect, wherein the inner diameter of the annular flexible portion is equal to or larger than the diameter of the opening end portion on the external space side of the communication passage. ..

According to the 16th aspect of the present invention, the communication passage has a second reduced diameter portion whose diameter becomes smaller from the intermediate portion toward the opening end portion on the external space side on the outer space side of the diaphragm member. And
The pressure according to any one of the ninth to fifteenth aspects, wherein the second diameter-reduced portion is formed in a tapered shape so as not to come into contact with the diaphragm member elastically deformed toward the second diameter-reduced portion. Provide a sensor unit.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to this embodiment.

<< Embodiment >>
A pressure-type rice cooker, which is an example of the pressure-type rice cooker according to the embodiment of the present invention, will be described. FIG. 1 is a schematic cross-sectional view of a pressure-type rice cooker according to an embodiment of the present invention. FIG. 2 is a perspective view of the pressure-type rice cooker of FIG.

As shown in FIG. 1, the pressure-type rice cooker according to the present embodiment is stored in a substantially bottomed tubular rice cooker body 1 in which a pot storage portion 1a is formed, and a pot storage portion 1a, and is stored in rice or rice. It is equipped with a pot 2 in which food such as water can be placed. An outer lid 3 having a hollow structure capable of opening and closing the upper opening of the rice cooker main body 1 is attached to the upper portion of the rice cooker main body 1. On the inside of the outer lid 3 (the side that covers the upper opening of the pot 2), a substantially disk-shaped inner lid 4 that can seal the upper opening of the pot 2 is detachably attached. In the present embodiment, the outer lid 3 and the inner lid 4 form a lid that can open and close the upper opening of the pot 2.

The pot storage portion 1a of the rice cooker main body 1 is composed of an upper frame 1b and a coil base 1c. The upper frame 1b has a tubular portion 1ba arranged so as to leave a predetermined gap with respect to the side wall of the stored pot 2, and an upper opening of the rice cooker main body 1 protruding outward from the upper portion of the tubular portion 1ba. It is provided with a flange portion 1bb that fits into the inner peripheral portion of the rice cooker. The upper end of the tubular portion 1ba supports a flange portion 2a provided around the upper opening of the pan 2.

The coil base 1c is formed in a bottomed tubular shape corresponding to the shape of the lower portion of the pan 2, and the upper portion thereof is attached to the lower end portion of the tubular portion 1ba of the upper frame 1b. A pot bottom heating unit 5, which is an example of a pot heating device for heating (induction heating) the pot 2, is attached to the outer peripheral surface of the coil base 1c. The pot bottom heating unit 5 is composed of an in-bottom heating coil 5a and an outside-bottom heating coil 5b. The in-bottom heating coil 5a is arranged so as to face the periphery of the central portion of the bottom of the pan 2 via the coil base 1c. The outer bottom heating coil 5b is arranged so as to face the corner portion of the bottom portion of the pan 2 via the coil base 1c.

An opening is provided in the central portion of the bottom of the coil base 1c. In the opening, a pot temperature sensor 6, which is an example of a pot temperature detecting unit for measuring the temperature of the pot 2, is arranged so as to be in contact with the bottom of the pot 2 housed in the pot storage portion 1a. .. Since the temperature of the pot 2 is substantially the same as the temperature of the object to be cooked in the pot 2, the pot temperature sensor 6 can detect the temperature of the object to be cooked in the pot 2 by detecting the temperature of the pot 2. it can.

The outer lid 3 includes an upper outer shell member 3a and a lower outer shell member 3b that form the outer shell of the outer lid 3. Further, the outer lid 3 includes a hinge shaft 3A. The hinge shaft 3A is an opening / closing shaft of the outer lid 3, and both ends thereof are rotatably fixed to the upper frame 1b of the rice cooker main body 1. A torsion coil spring 7 is attached around the hinge shaft 3A. The torsion coil spring 7 elastically biases the outer lid 3 in the direction away from the upper opening of the pan 2 (opening direction) with the hinge shaft 3A as the center.

A lid opening device 8 is provided inside the outer lid 3. The lid opening device 8 keeps the state in which the outer lid 3 closes the upper opening of the pot 2 by engaging with a part of the rice cooker main body 1. On the other hand, in the lid opening device 8, when the lid opening button 81 (see FIG. 2) provided on the rice cooker main body 1 or the outer lid 3 is pressed while the outer lid 3 closes the upper opening of the pot 2. It rotates around the hook shaft 8A in the direction of arrow A1. As a result, the lid opening device 8 and a part of the rice cooker main body 1 are disengaged, and the outer lid 3 is separated from the upper opening of the pot 2 about the hinge shaft 3A by the urging force of the torsion coil spring 7. Rotate to. As a result, the outer lid 3 is in an open state that does not block the upper opening of the pot 2. The outer lid 3 is configured to stop the rotation when, for example, the outer lid 3 is rotated 90 degrees around the hinge shaft 3A from a position where the upper opening of the pot 2 is closed.

A recess 3d is provided in the vicinity of the hinge shaft 3A of the upper outer member 3a. A steam cylinder 9 is detachably attached to the recess 3d. At the bottom of the recess 3d, a steam escape hole 3da is provided so that excess steam in the pot 2 can be discharged toward the steam cylinder 9. The upper wall of the steam cylinder 9 is provided with a steam relief hole 9a so that excess steam in the pot 2 can be discharged to the outside of the rice cooker.

The inner lid 4 is provided with a steam discharge hole 4a for discharging the steam in the pot 2 and a steam discharge hole 4b. The diameter of the steam discharge hole 4b is larger than the diameter of the steam discharge hole 4a, and is set to be, for example, twice or more the diameter of the steam discharge hole 4a. The diameter of the steam discharge hole 4a is, for example, 4 mm, and the diameter of the steam discharge hole 4b is, for example, 10 mm.

Further, the inner lid 4 is provided with a pressure suppression valve 10 capable of opening and closing the steam discharge hole 4a and a pressure reducing valve 11 capable of opening and closing the steam discharge hole 4b.

The pressure suppression valve 10 is a valve that suppresses the pressure in the pan 2 from rising above a predetermined value (for example, 1.2 atm) higher than the atmospheric pressure. In the present embodiment, the pressure suppression valve 10 is composed of balls and closes the steam discharge hole 4a by its own weight. On the other hand, when the pressure in the pot 2 becomes larger than its own weight (for example, when it becomes 1.2 atm or more), the pressure suppression valve 10 is pushed only by the pressure in the pot 2 and is pushed from the steam discharge hole 4a. Separate and open the steam discharge hole 4a.

The pressure reducing valve 11 is configured to be moved by the pressure reducing valve moving mechanism 12 to a closed position for closing the steam discharge hole 4b and an open position for opening the steam discharge hole 4b.

The outer lid 3 is provided with a pressure reducing valve moving mechanism 12 for moving the pressure reducing valve 11 so as to open and close the steam discharge hole 4b. The pressure reducing valve moving mechanism 12 is configured to press the pressure reducing valve 11 with a pressure larger than a predetermined value (for example, 1.2 atm) to hold the pressure reducing valve 11 in the closed position. Further, the pressure reducing valve moving mechanism 12 controls the pressure reducing valve 11 from the closed position by the control of the control unit 14 described later at a predetermined timing when the pressure in the pan 2 becomes a predetermined value (for example, 1.2 atm) or more. It is configured to move to the open position. As a result, the pressure in the pot 2 can be reduced at once (for example, reduced from 1.2 atm to 1.0 atm), the water in the pot 2 can be suddenly boiled, and the rice grains in the pot 2 can be agitated.

In addition, various information such as rice cooking course and rice cooking time can be displayed on the outer lid 3, and a specific rice cooking course can be selected from a plurality of rice cooking courses such as white rice course, brown rice course, and white rice (soft) course. Display operation unit 13 is provided. The display operation unit 13 includes a liquid crystal display 13A that displays various information such as the rice cooking course and the rice cooking time, and a plurality of buttons 13B that instruct the execution of rice cooking start, cancellation, reservation, etc. in addition to the selection of the rice cooking course. ing. The user can select a specific rice cooking course by pressing the plurality of buttons 13B and instruct the start of rice cooking while referring to various information displayed on the liquid crystal display 13A.

Further, a control unit 14 is mounted inside the rice cooker main body 1. The control unit 14 includes a storage unit that stores a plurality of rice cooking sequences for cooking rice. Here, in the "rice cooking sequence", when the four main steps of preheating, raising the temperature, maintaining boiling, and steaming are performed in order, the energizing time, heating temperature, heating time, heating output, etc. are predetermined in each step. The procedure for cooking rice. Each rice cooking sequence corresponds to one of a plurality of rice cooking courses. The control unit 14 controls the pot bottom heating unit 5 and the pressure reducing valve moving mechanism 12 based on the rice cooking course selected by the display operation unit 13 and the detection temperature of the pot temperature sensor 6, and executes the rice cooking process.

FIG. 3 is a partially cutaway side view of the pressure-type rice cooker of FIG. FIG. 4 is a plan view showing a state in which the parts on the upper outer shell member 3a side of the outer lid 3 are removed from the pressure type rice cooker of FIG. FIG. 5 is a perspective view showing a part of the parts of FIG. 4 in an exploded manner.

As shown in FIGS. 3 to 5, the outer lid 3 has a built-in pressure sensor unit 21 for detecting the pressure in the pan 2. More specifically, the pressure sensor unit 21 is attached to the lower outer member 3b of the outer lid 3.

As shown in FIG. 3, the lower outer shell member 3b of the outer lid 3 is provided with a through hole 3c at the mounting position of the pressure sensor unit 21. The inner lid 4 is provided with a through hole 4c at a position facing the through hole 3c when the inner lid 4 is attached to the lower outer shell member 3b of the outer lid 3.

FIG. 6 is an exploded perspective view of the pressure sensor unit 21 from diagonally below. FIG. 7 is an exploded perspective view of the pressure sensor unit 21 viewed from diagonally above. FIG. 8 is an assembled cross-sectional view of the pressure sensor unit 21.

As shown in FIGS. 6 to 8, the pressure sensor unit 21 includes a pot-side packing 22, a pot-side cap 23, a diaphragm member 24, a sensor case 25, a sensor-side packing 26, a pressure sensor 27, and a sensor. It is provided with a side cap 28.

The pot-side packing 22 is a tubular elastic body. The pot-side packing 22 is configured to seal the periphery of the through hole 3c of the outer lid 3 and the through hole 4c of the inner lid 4 when the inner lid 4 is attached to the lower outer member 3b of the outer lid 3. .. The pot-side packing 22 has an annular bent portion 221 having an enlarged diameter so that the inner lid 4 can absorb the pressure received when the inner lid 4 is attached to the lower outer shell member 3b of the outer lid 3.

The pan-side cap 23 is a substantially disk-shaped connection that connects the small-diameter cylindrical portion 231 and the large-diameter cylindrical portion 232, and the sensor-side end portion 231a of the small-diameter cylindrical portion 231 and the pan-side end portion 232a of the large-diameter cylindrical portion 232. It is provided with a unit 233. The pot-side packing 22 is detachably attached to the outer peripheral surface of the small-diameter cylindrical portion 231 of the pot-side cap 23. The connecting portion 233 includes a center hole 233a, and the small-diameter cylindrical portion 231 and the large-diameter cylindrical portion 232 communicate with each other through the center hole 233a. The outer peripheral portion of the connecting portion 233 is formed so as to project outward from the large-diameter cylindrical portion 232. The outer peripheral portion of the connecting portion 233 is provided with a plurality of engaging holes 233b that penetrate in the thickness direction and into which a plurality of engaging claw portions 283 of the sensor side cap 28, which will be described later, are inserted.

The diaphragm member 24 is made of a bottomed cylindrical elastic body. The diaphragm member 24 includes a circular membrane portion 241 and a cylindrical portion 242 connected to the outer peripheral portion of the membrane portion 241. The cylindrical portion 242 is connected to the outer peripheral portion of the film portion 241 at the pot side end portion 242a. The film portion 241 has an annular flexible portion 241a protruding toward the pan 2 in the inelastically deformed state.

The sensor case 25 includes an outer cylinder portion 251, an inner cylinder portion 252, and a diaphragm mounting portion 253 arranged between the outer cylinder portion 251 and the inner cylinder portion 252. The outer cylinder portion 251 is formed in a substantially cylindrical shape, and a part thereof is formed so as to be recessed inward. The inner cylinder portion 252 is formed in a cylindrical shape having a diameter smaller than that of the outer cylinder portion 251. The diaphragm mounting portion 253 is formed in a cylindrical shape. The cylindrical portion 242 of the diaphragm member 24 is attached so as to be in close contact with the outer peripheral surface of the diaphragm mounting portion 253 of the sensor case 25 and the inner peripheral surface of the large diameter cylindrical portion 232 of the pot-side cap 23.

The outer cylinder portion 251 of the sensor case 25 and the diaphragm mounting portion 253 are connected by a substantially annular connecting portion 254. The pot-side end 253a of the diaphragm mounting portion 253 and the pot-side end 252a of the inner cylinder portion 252 are connected by a substantially disk-shaped connecting portion 255. The connecting portion 255 is provided with a center hole 255a having a diameter smaller than the inner diameter of the inner cylinder portion 252 and the inner diameter of the small diameter cylindrical portion 231.

The sensor-side packing 26 is made of a tubular elastic body. The sensor-side packing 26 has a cylindrical portion 261 and a flange portion 262 that protrudes outward from the sensor-side end portion 261a of the cylindrical portion 261. The sensor-side packing 26 is inserted into the inner cylinder portion 252 of the sensor case 25 so that the opening 261c of the pan-side end portion 261b of the cylindrical portion 261 communicates with the center hole 255a of the connecting portion 255 of the sensor case 25. ..

The pressure sensor 27 includes a substrate 271 and a pressure sensor element 272 mounted on one surface of the substrate 271 to detect pressure. The pressure sensor element 272 is composed of, for example, a piezo element. The substrate 271 is provided with a through hole 271a at a position facing the pressure sensor element 272. The pressure sensor element 272 includes a cylindrical portion 272a that projects toward the other surface side of the substrate 271 through the through hole 271a. The cylindrical portion 272a is inserted inside the sensor-side packing 26. The sensor-side packing 26 is attached so as to be in close contact with the outer peripheral surface of the cylindrical portion 272a of the pressure sensor element 272 and the inner peripheral surface of the inner cylinder portion 252 of the sensor case 25. In this mounted state, the flange portion 262 of the sensor-side packing 26 is located in the through hole 271a of the substrate 271 of the pressure sensor 27. Further, as shown in FIG. 8, a lead wire 29 for electrically connecting the pressure sensor element 272 to the control unit 14 or the like is attached to the substrate 271.

The sensor-side cap 28 includes a cylindrical portion 281, a top wall portion 282, and a plurality of engaging claw portions 283 protruding from the outer peripheral portion of the top wall portion 282 toward the outer peripheral portion of the connecting portion 233 of the pot-side cap 23. I have. The sensor-side cap 28 is attached to the pan-side cap 23 so that the plurality of engaging claws 283 are inserted into and engaged with the plurality of engaging holes 233b of the connecting portion 233 of the pan-side cap 23. In this mounted state, the cylindrical portion 281 and the top wall portion 282 are positioned so as to cover the pressure sensor element 272.

In the present embodiment, as shown in FIG. 8, the inside of the pot 2 and the pressure sensor are formed by the space surrounded by the pot side cap 23, the sensor case 25, and the pot side end portion 261b of the cylindrical portion 261 of the sensor side packing 26. A communication passage CP that communicates with 27 is configured. The diaphragm member 24 is provided in the intermediate portion of the communication passage CP so as to close the communication passage CP. As a result, the space S1 in the communication passage CP between the diaphragm member 24 and the pressure sensor 27 becomes a closed space.

According to this configuration, since the space S1 on the pressure sensor 27 side of the communication passage CP is a closed space by the diaphragm member 24, it is possible to prevent the steam generated in the pot 2 from coming into direct contact with the pressure sensor 27. be able to. Further, since the space S1 is a closed space, the space S1 functions as a heat insulating space. For example, when the temperature of the steam in the pot 2 is 100 degrees, the temperature of the space S1 is lower than 100 degrees (for example, 60 degrees). As a result, the temperature rise of the pressure sensor 27 can be suppressed. Therefore, according to the present embodiment, it is possible to prevent the pressure sensor 27 from failing or deteriorating due to the moisture content of the steam or the temperature.

Further, in the present embodiment, the pot side end portion 231b of the small diameter cylindrical portion 231 of the pot side cap 23 constitutes the open end portion on the pot 2 side of the continuous passage CP. Further, the sensor-side packing 26 constitutes an open end portion of the communication passage CP on the pressure sensor 27 side. The large-diameter cylindrical portion 232 of the pot-side cap 23 is located in the middle portion of the communication passage CP. Further, the diameter of the opening end portion on the pot 2 side of the communication passage CP is larger than the diameter of the opening end portion on the pressure sensor 27 side of the communication passage CP, and is smaller than the diameter of the intermediate portion of the communication passage CP.

According to this configuration, the diameters of the opening end on the pot 2 side of the connecting passage CP and the intermediate portion of the connecting passage CP are larger than the diameter of the opening end on the pressure sensor 27 side of the connecting passage CP. It is possible to prevent the opening end portion on the pot 2 side and the intermediate portion of the continuous passage CP from being blocked by the dew condensation water. On the contrary, since the diameter of the opening end on the pressure sensor 27 side of the communication passage CP is smaller than the diameter of the opening end on the pot 2 side of the communication passage CP, the volume of the space S1 can be reduced. As a result, even if the elastic deformation of the membrane portion 241 of the diaphragm member 24 is small, the rate of volume change in the space S1 is large, so that the detection accuracy of the pressure sensor 27 can be improved.

Further, in the present embodiment, the surface 255b on the pot 2 side of the connecting portion 255 of the sensor case 25 has a first reduced diameter whose diameter decreases from the intermediate portion of the communication passage CP toward the opening end portion on the pressure sensor 27 side. Make up the part. As shown in FIG. 9, the surface 255b of the connecting portion 255 is formed to have substantially the same shape as the shape in which the diaphragm member 24 is elastically deformed (maximum deformed) toward the connecting portion 255.

According to this configuration, it is possible to prevent the connecting portion 255 and the diaphragm member 24 from coming into contact with each other and hindering the elastic deformation of the diaphragm member 24. Further, the volume of the space S1 can be made as small as possible to improve the detection accuracy of the pressure sensor 27.

The atmospheric pressure is P 0 , the pressure received by the diaphragm member 24 when the diaphragm member 24 is elastically deformed (maximum deformation) toward the connecting portion 255 is P1, and the diaphragm member 24 and the surface 255b of the connecting portion 255 are formed. When the volume of the enclosed space S2 is Vk and the volume of the space S3 communicating the surface 255b of the connecting portion 255 and the opening end on the pressure sensor 27 side of the communication passage CP is Va, P0 (Va + Vk) / It is preferable to satisfy the relationship of P1 and Va> 1. According to this configuration, it is possible to more reliably prevent the connecting portion 255 and the diaphragm member 24 from coming into contact with each other and hindering the elastic deformation of the diaphragm member 24.

Further, in the present embodiment, the diaphragm member 24 includes an annular flexible portion 241a protruding toward the pan side 2 in the inelastically deformed state. According to this configuration, not only the diaphragm member 24 itself is stretched, but also the flexible portion 241a is stretched, so that the diaphragm member 24 can be easily elastically deformed. As a result, for example, when the temperature of the space S1 (for example, 60 degrees) becomes higher than the temperature in the pot 2 (for example, 20 degrees) and the air in the space S1 expands, as shown in FIG. The film portion 241 of the 24 can be easily elastically deformed so as to protrude toward the pot 2. As a result, the pressure in the space S1 can be made the same as the pressure in the pot 2, and the pressure sensor 27 can prevent the pressure in the pot 2 from being erroneously detected.

As shown in FIG. 11, the flexible portion 241a may be provided so as to project toward the pressure sensor 27 in the inelastic deformation state. That is, the flexible portion 241a may be provided so as to project in the thickness direction of the diaphragm member 24. Even with this configuration, not only the diaphragm member 24 itself is stretched, but also the flexible portion 241a is stretched, so that the diaphragm member 24 can be easily elastically deformed. As shown in FIG. 11, when the flexible portion 241a is provided so as to project toward the pressure sensor 27, the flexible portion 241a comes into contact with the surface 255b of the connecting portion 255 and the elastic deformation of the diaphragm member 24 is hindered. May be done. Therefore, as shown in FIG. 8, the flexible portion 241a is preferably provided so as to project toward the pan side 2 in the inelastically deformed state.

Further, the inner diameter of the flexible portion 241a is preferably as large as possible, and as shown in FIG. 8, it is preferably equal to or larger than the diameter of the opening end portion on the pot 2 side of the continuous passage CP. Thereby, the elastic deformation of the film portion 241 can be facilitated.

Further, in the present embodiment, the surface 233c of the connecting portion 233 of the pot side cap 231 facing the diaphragm member 24 becomes smaller in diameter from the intermediate portion of the communication passage CP toward the opening end portion on the pot 2 side. It constitutes a reduced diameter portion. As shown in FIG. 10, the surface 233c of the connecting portion 233 is formed in a tapered shape so as not to come into contact with the diaphragm member 24 elastically deformed toward the surface 233c. According to this configuration, it is possible to prevent the connecting portion 233 and the diaphragm member 24 from coming into contact with each other and hindering the elastic deformation of the diaphragm member 24. Further, for example, even when dew condensation water is generated on the surface 233c of the connecting portion 233, the dew condensation water can be returned to the pot 2 side.

The present invention is not limited to the above embodiment, and can be implemented in various other aspects. For example, in the above, as shown in FIG. 8, the membrane portion 241 of the diaphragm member 24 is shown to be flat except for the flexible portion 241a in the inelastically deformed state, but the present invention is not limited thereto. .. For example, as shown in FIG. 12, the membrane portion 241 of the diaphragm member 24 may be configured such that the inner portion of the bending portion 241a bends in the direction opposite to the bending portion 241a in the inelastically deformed state. The same effect can be obtained by this configuration.

Further, in the above description, the pressure sensor unit 21 is used to detect the pressure in the space inside the pot 2 of the pressure type rice cooker, but the present invention is not limited to this. The pressure sensor unit 21 can be used to detect the pressure in an external space where steam is generated, such as the space inside the pressure cooker.

Further, in the above, the pressure sensor unit 21 is provided with the pan-side packing 22, but the pressure sensor unit 21 may not be provided with the pan-side packing 22.

Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various modifications and modifications are obvious to those skilled in the art. It should be understood that such modifications and modifications are included therein, as long as they do not deviate from the scope of the invention according to the appended claims.

Since the present invention can improve the pressure detection accuracy, it is particularly useful for pressure cookers such as pressure cookers and pressure cookers, which are required to detect the pressure in the external space where steam is generated. ..

1 Rice cooker body 1A Hing part 1a Pot storage part 1b Upper frame 1ba Cylindrical part 1bb Flange part 1c Coil base 2 Pot 2a Flange part 3 Outer lid 3A Hinge shaft 3a Upper outer member 3b Lower outer member 3c Through hole 3d Concave 3da Relief hole 4 Inner lid 4a, 4b Steam discharge hole 4c Through hole 5 Pot bottom heating unit 5a Bottom heating coil 5b Bottom outside heating coil 6 Pot temperature sensor 7 Twisting coil spring 8 Lid opening device 8A Hook shaft 9 Steam cylinder 9a Steam relief hole 10 Pressure suppression valve 11 Pressure reducing valve 12 Pressure reducing valve movement mechanism 13 Display operation unit 13A Liquid crystal display 13B Button 14 Control unit 21 Pressure sensor unit 22 Pot side packing 221 Bending part 23 Pot side cap 231 Small diameter cylindrical part 231a Sensor side end 231b Pot Side end (open end on the pot side of the continuous passage)
232 Large diameter cylindrical part 232a Pot side end part 233 Connecting part 233a Center hole 233b Engagement hole 233c Surface (second reduced diameter part)
24 Septal member 241 Membrane part 241a Bending part 242 Cylindrical part 242a Pot side end 25 Sensor case 251 Outer cylinder part 252 Inner cylinder part 252a Pot side end part 253 Diaphragm mounting part 253a Pot side end part 254, 255 Connecting part 255a Center hole 255b surface (first reduced diameter part)
26 Sensor side packing 261 Cylindrical part 261a Sensor side end part 261b Pot side end part (open end part on the pressure sensor side of the communication passage)
261c Opening 262 Flange part 27 Pressure sensor 271 Board 271a Through hole 272 Pressure sensor element 272a Cylindrical part 28 Sensor side cap 281 Cylindrical part 282 Top wall part 283 Engagement claw part 29 Lead wire 81 Open lid button

Claims (14)

With a pot
A lid that opens and closes the upper opening of the pot,
A pressure sensor unit built into the lid and detecting the pressure inside the pan,
With
The pressure sensor unit is
A pressure sensor that detects pressure and
A communication passage that communicates the inside of the pot with the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. It has become
A pressure-type cooker in which the diameter of the opening end on the pot side of the communication passage is larger than the diameter of the opening end on the pressure sensor side of the communication passage and smaller than the diameter of the middle portion of the communication passage. The communication passage has a first reduced diameter portion whose diameter becomes smaller from the intermediate portion toward the opening end portion on the pressure sensor side on the pressure sensor side of the diaphragm member.
The pressure cooker according to claim 1, wherein the shape of the first reduced diameter portion is substantially the same as the shape of the diaphragm member elastically deformed toward the first reduced diameter portion. The atmospheric pressure is P 0, and the pressure received by the diaphragm member when the diaphragm member is elastically deformed toward the first reduced diameter portion is P 1, and the space surrounded by the diaphragm member and the first reduced diameter portion. When the volume of the space that communicates the opening of the first reduced diameter portion and the opening end of the communication passage on the pressure sensor side is Va, P0 (Va + Vk) / P1 · Va The pressure-type cooker according to claim 2 , which satisfies the relationship of> 1. The pressure-type cooker according to any one of claims 1 to 3, wherein the diaphragm member has an annular flexible portion protruding in the thickness direction of the diaphragm member in an inelastically deformed state. The pressure-type cooker according to claim 4 , wherein the annular flexible portion projects toward the pan. The pressure-type cooker according to claim 4 or 5 , wherein the inner diameter of the annular flexible portion is equal to or larger than the diameter of the opening end portion on the pot side of the communication passage. The communication passage has a second reduced diameter portion on the pot side of the diaphragm member, the diameter of which decreases from the intermediate portion toward the opening end on the pot side.
The pressure according to any one of claims 1 to 6 , wherein the second reduced diameter portion is formed in a tapered shape so as not to come into contact with the diaphragm member elastically deformed toward the second reduced diameter portion. Type cooker. A pressure sensor that detects pressure and
A communication passage that communicates the external space where steam is generated and the pressure sensor,
With
A diaphragm member made of an elastic body is provided in the middle portion of the communication passage so as to close the communication passage, and the space in the communication passage between the diaphragm member and the pressure sensor becomes a closed space. It has become
A pressure sensor unit in which the diameter of the opening end on the external space side of the communication passage is larger than the diameter of the opening end on the pressure sensor side of the communication passage and smaller than the diameter of the middle portion of the communication passage . The communication passage has a first reduced diameter portion whose diameter becomes smaller from the intermediate portion toward the opening end portion on the pressure sensor side on the pressure sensor side of the diaphragm member.
The pressure sensor unit according to claim 8, wherein the shape of the first reduced diameter portion is substantially the same as the shape of the diaphragm member elastically deformed toward the first reduced diameter portion. The atmospheric pressure is P 0, and the pressure received by the diaphragm member when the diaphragm member is elastically deformed toward the first reduced diameter portion is P 1, and the space surrounded by the diaphragm member and the first reduced diameter portion. When the volume of the space that communicates the opening of the first reduced diameter portion and the opening end of the communication passage on the pressure sensor side is Va, P0 (Va + Vk) / P1 · Va The pressure sensor unit according to claim 9 , which satisfies the relationship of> 1. The pressure sensor unit according to any one of claims 8 to 10 , wherein the diaphragm member has an annular flexible portion protruding in the thickness direction of the diaphragm member in an inelastically deformed state. The pressure sensor unit according to claim 11 , wherein the annular flexible portion projects toward the external space side. The pressure sensor unit according to claim 11 or 12 , wherein the inner diameter of the annular flexible portion is equal to or larger than the diameter of the opening end portion on the external space side of the communication passage. The communication passage has a second reduced diameter portion whose diameter decreases from the intermediate portion toward the opening end portion on the external space side on the outer space side of the diaphragm member.
The pressure according to any one of claims 8 to 13 , wherein the second reduced diameter portion is formed in a tapered shape so as not to come into contact with the diaphragm member elastically deformed toward the second reduced diameter portion. Sensor unit.

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