cooker

Abstract

To provide a cooker that can reduce blowing noise which is generated at a steam port of a cooker when returning the inner space of an inner pot under a pressurized state to an atmospheric pressure.SOLUTION: A cooker 100 includes: an inner pot 130; a heating unit 113 for heating the inner pot 130; a valve mechanism PS for opening and closing a communication path connecting between the inner space of the inner pot 130 and an outer space with a valve body VB; a valve seat ID2 provided on the valve body VB; and a valve mechanism control unit 143 for controlling the pressing force of the valve body VB against the valve seat ID2. The valve mechanism control unit 143 alternately executes, on the valve body VB, " control of a first output for generating a first pressing force of the valve body VB against the valve seat ID2", and "control of a second output for generating a second pressing force of the valve body VB against the valve seat ID2, which is a pressing force lower than the first pressing force". The valve mechanism control unit 143 performs a first pressure reduction control when returning the inner space of the inner pot 130 to an atmospheric pressure.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a cooking appliance such as a rice cooker. [Background technology]

[0002] In the past, a cooking device has been proposed that includes "an inner pot, a cooking device main body that houses the inner pot, a lid body that covers the cooking device main body, and an inner lid that is attached to the lid body and covers the inner pot, the inner lid having a pressure adjustment hole that passes through it, and the lid body having a valve body that is disposed above the pressure adjustment hole and that can be displaced in a direction perpendicular to the pressure adjustment hole and that opens and closes the pressure adjustment hole, and a pressure adjustment mechanism that is connected to the valve body and includes a drive means that displaces the valve body, and the drive means is a solenoid that has a fixed part that is fixed to the lid body and a movable part that engages with the valve body and moves in the displacement direction of the valve body" (see, for example, JP 2024-015749 A, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2024-015749 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional cookers that use a push solenoid for pressure control, when the internal space of the inner pot, which is pressurized, is returned to atmospheric pressure, a loud blasting noise can sometimes be generated from the steam vent of the cooker.

[0005] An object of the present invention is to provide a cooker that can reduce the blowing noise generated from the steam vent of the cooker when the internal space of the inner pot, which is in a pressurized state, is returned to atmospheric pressure. [Means for solving the problem]

[0006] A cooking appliance according to a first aspect of the present invention includes an inner pot, a heating unit, a valve mechanism, a valve seat, and a valve mechanism control unit. The heating unit heats the inner pot. The valve mechanism uses a valve element to open and close a communication passage that connects the inner space of the inner pot with the outside space. The valve seat is provided for the valve element. The valve mechanism control unit controls the pressure of the valve element against the valve seat. In this cooking appliance, the valve mechanism control unit alternately controls the valve element between "controlling a first output to generate a first pressure on the valve element against the valve seat" and "controlling a second output to generate a second pressure on the valve element against the valve seat, the second pressure being lower than the first pressure." Furthermore, in this cooking appliance, the valve mechanism control unit performs first pressure reduction control when the inner space of the inner pot is returned to atmospheric pressure. In the first pressure reduction control, the ON ratio of the second output is reduced by a fixed value each time the second output is controlled. After the ON ratio of the second output reaches a second specific ON ratio, the ON ratio of the first output is reduced to the first specific ON ratio.

[0007] According to the above configuration, it is possible to reduce the blowing noise generated from the steam vent of the cooking appliance.

[0008] In a cooking appliance according to a second aspect of the present invention, when the ON ratio of the second output in the first pressure reduction control does not reach the second specific ON ratio and the appliance transitions to the next pressure reduction control, the second pressure reduction control, the ON ratio of the second output in the first pressure reduction control is carried over as the ON ratio of the second output in the second pressure reduction control.

[0009] According to the above configuration, even when the control shifts to the second pressure reduction control before the ON ratio of the second output reaches the second specific ON ratio in the first pressure reduction control, the blowing noise generated from the steam vent of the cooking appliance can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] A cross-sectional view of a rice cooker according to an embodiment of the present invention taken along a plane passing through the center in the left-right direction and along the up-down and front-rear direction. This figure shows the state in which the inner lid is attached to the lid body and the valve body of the valve of the pressure adjustment mechanism opens the pressure adjustment port of the valve seat forming member of the inner lid. [Figure 2] 1 is a bottom view of the lid according to the embodiment of the present invention, showing the state in which the inner lid is attached to the lid. [Figure 3] 1 is a bottom view of the lid according to the embodiment of the present invention, showing a state in which the inner lid is not attached to the lid. [Figure 4] FIG. 2 is an enlarged view of the lid shown in FIG. [Figure 5] This is an enlarged view of the pressure adjustment mechanism and its vicinity shown in Figure 2. Note that this figure shows a state in which the valve body of the pressure adjustment mechanism opens the pressure adjustment port of the valve seat forming member of the inner lid. [Figure 6] FIG. 2 is an enlarged view of the lid shown in FIG. [Figure 7] 1 is a plan view of a lower exterior member, a pressure adjustment mechanism, a flow path forming portion, a reinforcing member, an opening / closing mechanism, an interlocking member, and a hinge mechanism of an exterior body according to an embodiment of the present invention. FIG. [Figure 8] FIG. 2 is a top perspective view of a lower exterior member, a pressure adjustment mechanism, a flow path forming portion, a reinforcing member, an opening / closing mechanism, an interlocking member, and a hinge mechanism of an exterior body according to an embodiment of the present invention. [Figure 9] FIG. 2 is a top perspective view of a lower exterior member, a flow path forming portion, a reinforcing member, an opening / closing mechanism, and a hinge mechanism of an exterior body according to an embodiment of the present invention. [Figure 10] FIG. 2 is an exploded top perspective view of a pressure adjustment mechanism according to an embodiment of the present invention. [Figure 11] 4 is a flowchart illustrating a method for controlling a pressure adjustment mechanism according to an embodiment of the present invention. [Figure 12] In a control method for a pressure adjustment mechanism according to an embodiment of the present invention, if the ON ratio of the second duty output in the first pressure reduction control does not reach 34% and a certain period of time elapses before transitioning to the second pressure reduction control, this is a flowchart showing the flow in which the second pressure reduction control is executed by carrying over the ON ratio of the second duty output in the first pressure reduction control as the ON ratio of the second duty output in the second pressure reduction control. [Figure 13] 10 is a flowchart showing a method for controlling a pressure adjustment mechanism according to modified example (B) of the embodiment of the present invention. [Figure 14] In a control method for a pressure adjustment mechanism according to a modified example (F) of an embodiment of the present invention, if the ON ratio of the second duty output in the first pressure reduction control does not reach 34% and a certain time elapses before transitioning to the second pressure reduction control, this is a flowchart showing the flow in which the second pressure reduction control is executed by carrying over the value of the ON ratio of the second duty output in the first pressure reduction control as is as the ON ratio of the second duty output in the second pressure reduction control. DETAILED DESCRIPTION OF THE INVENTION

[0011] <Configuration of rice cooker according to an embodiment of the present invention> As shown in Figure 1, a rice cooker 100 according to an embodiment of the present invention is mainly composed of a main body 110, an inner pot 130, a lid 140, and a hinge mechanism 150. These components will be described in detail below.

[0012] (1) Main unit 1, the main body 110 is mainly composed of a housing 111, an induction heating coil 113, a heat retention heater HT, a center sensor 114, a blower fan 115, a heat sink 116, a control board 118, an automatic retractable power cord unit 119, and a latched portion 120. These components will be described in detail below.

[0013] (1-1) Cabinet 1, the housing 111 is mainly composed of a housing 111a, a shoulder member 111c, a protective frame 111d, etc. These components will be described in detail below.

[0014] (1-1-1) Containment Unit As shown in Fig. 1, the housing 111a is mainly composed of a side wall Aa and a bottom wall Ab. These components will be described in detail below. As shown in Fig. 1, the housing 111a houses an induction heating coil 113, a heat retention heater HT, a center sensor 114, a blower fan 115, a heat sink 116, a control board 118, an automatic retractable power cord unit 119, and a locked portion 120.

[0015] The side wall Aa is an enclosing wall portion having a generally rounded rectangular shape in a plan view, and forms the side surface of the main body 110, as shown in Fig. 1. Also, as shown in Fig. 1, a shoulder member 111c is attached to the upper end of the side wall Aa.

[0016] The bottom wall Ab is a wall portion having a substantially rounded rectangular shape in a plan view, and as shown in FIG. 1, closes the lower opening of the side wall Aa. Also, as shown in FIG. 1, the bottom wall Ab has leg portions Ab1 extending downward. An exhaust port (not shown) for discharging air inside the housing 111 to the outside of the housing 111 is formed in the front portion of the bottom wall Ab, and an air intake port Ab2 (see FIG. 1) for drawing air outside the housing 111 into the inside of the housing 111 is formed in the rear portion of the bottom wall Ab. Note that, as shown in FIG. 1, a blower fan 115 is disposed directly above the air intake port Ab2. When the blower fan 115 is driven, air outside the housing 111 is drawn into the inside of the housing 111 through the air intake port Ab2, and the resulting air flow causes air inside the housing 111 to be discharged to the outside of the housing 111 through the exhaust port.

[0017] (1-1-2) Shoulder member As described above, the shoulder member 111c is attached to the upper end of the side wall Aa of the container 111a. As shown in Fig. 1, the flange portion Db of the protective frame 111d is attached to the underside of the shoulder member 111c. An opening for passing the inner bowl 130 is formed in the center of the shoulder member 111c. An opening for passing the claw portion of the latched portion 120 is also formed in the front of the shoulder member 111c (more specifically, in the area forward of the opening for passing the inner bowl 130).

[0018] (1-1-3) Protective frame The protective frame 111d accommodates the inner pot 130 and supports the shoulder member 111c. As shown in FIG. 1, it is primarily composed of an inner pot housing portion Da and a flange portion Db. The inner pot housing portion Da is a bowl-shaped portion that covers the outer periphery of the inner pot 130 (see FIG. 1) and is connected to the bottom wall Ab of the housing body 111a. Also, as shown in FIG. 1, an opening is formed in the center of the bottom wall of the inner pot housing portion Da to allow the center sensor 114 to pass through. As shown in FIG. 1, the flange portion Db extends outward from the top end of the inner pot housing portion Da and is attached to the underside of the shoulder member 111c as described above.

[0019] (1-2) Induction heating coil Induction heating coil 113 is an induction heating source that inductively heats inner pot 130, and is arranged outside the bottom wall and lower end of the side wall of inner pot accommodating portion Da of protective frame 111d as shown in FIG.

[0020] (1-3) Heater The warming heater HT is an annular heater used during rice cooking and warming operations, and as shown in FIG. 1, is placed outside the upper end of the side wall of the inner pot accommodating section Da of the protective frame 111d.

[0021] (1-4) Center sensor The center sensor 114 is a sensor that detects the temperature of the inner pot 130 and the presence or absence of the inner pot 130. As shown in FIG. 1, it protrudes upward through an opening in the bottom wall of the inner pot housing section Da of the protective frame 111d. The center sensor 114 is biased upward by a biasing member (not shown) such as a coil spring. In other words, the center sensor 114 is free to protrude and retract in the vertical direction. When the inner pot 130 is housed in the protective frame 111d, the center sensor 114 comes into contact with the bottom wall 131 of the inner pot 130 to measure the temperature of the inner pot 130.

[0022] (1-5) Blower fan As described above, the blower fan 115 is disposed directly above the intake port Ab2 in the bottom wall Ab of the housing 111a. When the blower fan 115 is driven, air from outside the housing 111 is sucked in through the intake port Ab2 in the bottom wall Ab of the housing 111a, flows into the inside of the housing 111, and is then sent upward. The air sent upward then passes through the heat sink 116 and is supplied to the control board 118 and the like, cooling them.

[0023] (1-6) Heat sink The heat sink 116 is a component for efficiently exchanging heat with the outside air, and is disposed above the blower fan 115 as shown in FIG.

[0024] (1-7) Control board The control board 118 is a board that constitutes a power supply circuit and has several heat-generating components mounted thereon. The control board 118 is disposed inside the housing 111a at the rear of the housing 111a as shown in Fig. 1, and is connected for communication with the microcomputer board CB and the like.

[0025] (1-8) Automatic retractable power cord unit The automatic retractable power cord unit 119 is composed of a power cord (not shown) and an automatic retraction mechanism (not shown), and is located inside the housing 111a at the rear end of the housing 111a as shown in FIG. 1. The power cord is composed of an attachment plug and an electric wire, etc. The attachment plug is located at the tip of the electric wire. The electric wire is wound around the automatic retraction mechanism so that it can be stretched.

[0026] (1-9)Locked part The latched portion 120 has a claw portion, and the latched portion 120 is attached to the shoulder member 111c so that the claw portion passes through an opening in the front of the shoulder member 111c. When the lid 140 is in the closed state, the claw portion OC5 of the lever member OC of the opening / closing mechanism 147 of the lid 140 is latched to the claw portion.

[0027] (2) Inner pot As shown in FIG. 1, inner pot 130 passes through the central opening of shoulder member 111c and is accommodated in inner pot accommodation section Da of protective frame 111d with a specified gap. Inner pot 130 is a multilayered body (clad material) made of various aluminum alloys, stainless steel alloys, etc., and is induction heated by induction heating coil 113. As shown in FIG. 1, inner pot 130 is composed of bottom wall section 131, tubular wall section 132, and flange section 133. Bottom wall section 131 is generally disc-shaped in plan view. Tube wall section 132 is generally cylindrical and extends upward from the outer edge of bottom wall section 131 as shown in FIG. 1. Flange section 133 is generally annular and extends outward from the upper end of tubular wall section 132 as shown in FIG. 1. As shown in FIG. 1, when the inner pot 130 is accommodated in the inner pot accommodating portion Da of the protective frame 111d with a predetermined gap between them, the flange portion 133 is positioned above the shoulder member 111c.

[0028] (3) Lid As shown in FIG. 1, lid 140 is intended to cover from above the opening of inner pot 130 housed in protective frame 111d of main body 110. It is positioned above main body 110 and attached to main body 110 via hinge mechanism 150 so as to be rotatable about hinge mechanism-side rotation shaft 151 of hinge mechanism 150. As shown in FIGS. 1 to 5, lid 140 is primarily composed of exterior body 141, microcomputer board CB, operation button group BT, information display panel DI, pressure adjustment mechanism 143, flow path forming section 144, lid locking mechanism 145, inner lid IL, reinforcing member 146, steam sensor (not shown), opening / closing mechanism 147, and interlocking member 148. These components are described in detail below.

[0029] (3-1) Exterior body The exterior body 141 is a substantially rectangular parallelepiped resin member, and as shown in Figures 1 to 5, is mainly composed of an upper exterior member UE and a lower exterior member LE. These components will be described in detail below. As shown in Figures 1 and 4, the exterior body 141 houses a microcomputer board CB, an information display panel DI, a pressure adjustment mechanism 143, a flow path forming section 144, a reinforcing member 146, a steam sensor, an opening / closing mechanism 147, an interlocking member 148, and the like.

[0030] The upper exterior member UE is a member having a substantially rounded rectangular shape in a plan view, and is attached to the lower exterior member LE so as to cover the lower exterior member LE from above, as shown in FIGS. 1 and 4. A first opening is formed in the front end of the top wall of the upper exterior member UE for exposing the top wall of the operation unit OA of the opening / closing mechanism 147, and a second opening is formed in the front part of the top wall of the upper exterior member UE behind the first opening for exposing the top surfaces of the operation buttons of the operation button group BT (see FIGS. 1 and 4). A third opening is formed in the rear part of the top wall of the upper exterior member UE for exposing a part of the flow path forming unit 144 (the part forming the exhaust port BO) (see FIGS. 1 and 4).

[0031] As shown in FIGS. 2 and 3, the lower exterior member LE has a generally rounded rectangular shape in bottom view, and is disposed between the solenoid PS of the pressure adjustment mechanism 143 and the valve seat portion-forming member ID of the inner lid IL as shown in FIGS. 4 and 5. As shown in FIGS. 2 to 5 and 7 to 9, the lower exterior member LE is primarily formed of an upper wall portion LE1, a side wall portion LE2, a lower wall portion LE3, a support portion LE4, an enclosure wall portion LE5, a cylindrical wall portion LE6, a spring mounting surface-forming wall portion LE7, a protrusion portion LE8, and a screw receiving portion LE9. As shown in FIG. 7, the upper wall portion LE1 has a generally rectangular shape in plan view. As shown in FIGS. 2, 3, and 7 to 9, openings LE1a are formed on the left and right sides of the front end of the upper wall portion LE1 to allow the extension portion OC4 and the claw portion OC5 of the lever member OC of the opening / closing mechanism 147 to pass through. As shown in Figures 2-4 and 7-9, an opening LE1b is formed in the center of the front end of the upper wall portion LE1, through which the inner lid lever LL of the lid locking mechanism 145 is positioned. As shown in Figures 3, 4, 5, and 9, an opening LE1c is formed in the center of the upper wall portion LE1, through which the rod portion RP and valve body VB of the pressure adjustment mechanism 143 pass. As shown in Figures 3 and 4, an opening LE1d is formed in the rear portion of the upper wall portion LE1 behind the opening LE1c, through which steam generated in the inner pot 130 flows into the space formed by the upper wall portion LE1, the surrounding wall portion LE5, and the flow passage forming portion 144. As shown in Figure 4, the opening LE1d is located inside the surrounding wall portion LE5. The side wall portion LE2 extends downward from the outer end of the upper wall portion LE1, as shown in Figures 4, 7-9. As shown in Figures 4 and 7 to 9, the lower wall portion LE3 extends outward from the lower end of the side wall portion LE2. As shown in Figures 2 to 4, the support portion LE4 extends forward from the left and right portions of the rear end of the side wall portion LE2. As shown in Figure 4, a gap LE4a is formed between the upper wall portion LE1 and the support portion LE4. When the inner lid IL is attached to the lid body 140, the supported portion IB2 of the inner lid ring IB of the inner lid IL enters this gap LE4a and is supported by the support portion LE4 (see Figure 4). The surrounding wall portion LE5 has a generally cylindrical shape and extends upward from the rear portion of the upper wall portion LE1 as shown in Figure 4.As shown in FIG. 4, a flow path forming portion 144 is attached to the upper end of the surrounding wall portion LE5. The cylindrical wall portion LE6 is generally cylindrical and, as shown in FIG. 4, extends upward from the edge of the opening LE1d in the upper wall portion LE1. Steam generated in the inner pot 130 passes through the opening LE1d in the upper wall portion LE1 and then flows inside the cylindrical wall portion LE6. As shown in FIGS. 4 and 7 to 9, the spring mounting surface forming wall portion LE7 extends upward from the center of the front end of the upper wall portion LE1 (more specifically, the portion in front of the opening LE1b). The spring mounting surface forming wall portion LE7 has a concave shape that is recessed toward the front. In other words, the spring mounting surface forming wall portion LE7 is formed by a front wall portion, a right wall portion extending rearward from the right end of the front wall portion, and a left wall portion extending rearward from the left end of the front wall portion. A coil spring of the lid locking mechanism 145 is disposed inside the spring mounting surface forming wall portion LE7, and one end of the coil spring of the lid locking mechanism 145 is attached to the rear surface of the front wall of the spring mounting surface forming wall portion LE7. As shown in FIGS. 3 to 5, the protrusions LE8 extend downward from three locations on the upper wall portion LE1 that are near the valve body VB of the pressure adjustment mechanism 143, and surround the opening LE1c of the upper wall portion LE1. More specifically, as shown in FIGS. 3 to 5, the protrusions LE8 extend downward from three locations on the upper wall portion LE1 around the opening LE1c (a front portion of the opening LE1c on the upper wall portion LE1, a right rear portion of the opening LE1c on the upper wall portion LE1, and a left rear portion of the opening LE1c on the upper wall portion LE1). When the inner lid IL is attached to the lid body 140, the lower end of the protrusion LE8 abuts against the base portion ID1 of the valve seat-forming member ID of the inner lid IL. As shown in FIGS. 5 and 9, the screw receiving portions LE9 extend upward from three locations on the upper wall portion LE1 around the opening LE1c (a portion of the upper wall portion LE1 in front of the opening LE1c, a portion of the upper wall portion LE1 to the right rear of the opening LE1c, and a portion of the upper wall portion LE1 to the left rear of the opening LE1c). A screw receiving hole for passing a screw SC is formed in the screw receiving portion LE9. Then, as shown in FIG. 5, this screw receiving hole overlaps with a screw receiving hole in the screw receiving portion SP6 of the support member SP of the pressure adjustment mechanism 143 to form a communication hole. By passing the screw SC through this communication hole, the support member SP of the pressure adjustment mechanism 143 is attached to the lower exterior member LE.

[0032] (3-2) Microcomputer board The microcomputer board CB is mounted with electronic components such as a microcomputer MC, and is communicatively connected to the information display panel DI, the solenoid PS of the pressure adjustment mechanism 143, the steam sensor, and the control board 118 of the main body 110. It is also communicatively connected to the induction heating coil 113, center sensor 114, warming heater HT, and blower fan 115 of the main body 110 via the control board 118 of the main body 110. The microcomputer MC of the microcomputer board CB is equipped with memory, which stores various programs and data for controlling rice cooking and keeping warm. The microcomputer MC of the microcomputer board CB executes each process in the rice cooker 100, controls the output of the induction heating coil 113 and warming heater HT of the main body 110, measures time, energizes the coil PD of the solenoid PS of the pressure adjustment mechanism 143 to perform pressure cooking, and stops pressure cooking by cutting off the energization of the coil PD of the solenoid PS of the pressure adjustment mechanism 143.

[0033] (3-3) Operation buttons The operation button group BT includes, for example, a rice cooking start button, a cancel button, etc. Furthermore, the upper surface of each operation button in the operation button group BT is exposed from the second opening in the top wall portion of the upper exterior member UE of the exterior body 141, as described above.

[0034] (3-4) Information display panel The information display panel DI is located behind the operation button group BT as shown in Figures 1 and 4. The information display panel DI displays various information such as rice cooking menu information and rice cooking progress information based on commands from the microcomputer MC on the microcomputer board CB.

[0035] (3-5) Pressure adjustment mechanism The pressure adjustment mechanism 143 adjusts the pressure inside the inner pot 130 to 1 atmosphere or higher when the lid 140 is closed and pressure cooking is in progress. As shown in Figures 4, 5, and 10, the pressure adjustment mechanism 143 is mainly composed of a solenoid PS, a rod portion RP, a valve body VB, a support member SP, and a plate member SQ. These components will be described in detail below, followed by a detailed description of the operation of the pressure adjustment mechanism 143.

[0036] (3-5-1) Solenoid The solenoid PS is a push-type solenoid, and as shown in Figures 4 and 5, is disposed above the upper wall portion LE1 of the lower exterior member LE of the exterior body 141. As shown in Figures 4, 5, and 10, the solenoid PS is mainly composed of a frame PA, a movable iron core PB, a fixed iron core PC, a coil PD, a coil spring PE, etc. These components will be described in detail below.

[0037] As shown in FIGS. 5 and 10, the frame PA is formed of a top wall portion PA1, a front wall portion PA2, a rear wall portion PA3, and a bottom wall portion PA4. As shown in FIG. 5, the movable core PB, the fixed core PC, the coil PD, and the coil spring PE are arranged inside these walls. The top wall portion PA1 has a substantially rectangular shape in a plan view. As shown in FIG. 5, an opening PA1a is formed in the center of the top wall portion PA1 to allow the upper ends of the movable core PB and the rod portion RP to pass through. As shown in FIGS. 5 and 10, the front wall portion PA2 extends downward from the front end of the top wall portion PA1. As shown in FIGS. 5 and 10, the rear wall portion PA3 extends downward from the rear end of the top wall portion PA1. As shown in FIGS. 5 and 10, the bottom wall portion PA4 extends from the lower end of the front wall portion PA2 to the lower end of the rear wall portion PA3. As shown in FIG. 5, an opening PA4a is formed in the center of the bottom wall portion PA4 to allow the lower end of the rod portion RP to pass through.

[0038] The movable core PB has a generally cylindrical shape and is movable in the vertical direction. As shown in FIGS. 4 and 5, a rod portion RP is disposed inside the movable core PB and attached to the movable core PB. The movable core PB is biased upward by a coil spring PE. When current is applied to the coil PD, the movable core PB is attracted to the fixed core PC against the biasing force of the coil spring PE and moves toward the fixed core PC (downward). At this time, the rod portion RP attached to the movable core PB also moves downward. When current is cut off from the coil PD, the movable core PB moves toward the opposite side (upward) of the fixed core PC due to the biasing force of the coil spring PE. At this time, the rod portion RP also moves upward.

[0039] The fixed core PC has a generally cylindrical shape and is disposed below the movable core PB and attached to the upper surface of the bottom wall portion PA4 of the frame PA, as shown in Figures 4 and 5. As shown in Figures 4 and 5, a rod portion RP passes through the inside of the fixed core PC.

[0040] The coil PD is formed by, for example, winding an insulated copper wire around a bobbin, and generates a magnetic flux when a current is passed through it. The coil PD is located around the movable iron core PB and the fixed iron core PC, as shown in Figure 4.

[0041] As shown in FIG. 5, the coil spring PE is disposed between the movable core PB and the fixed core PC, and biases the movable core PB upward as described above.

[0042] (3-5-2) Rod part As shown in FIGS. 4, 5, and 10, the rod portion RP extends vertically and passes through an opening PA1a in the top wall portion PA1 of the frame PA of the solenoid PS, an opening PA4a in the bottom wall portion PA4 of the frame PA, the interior of the movable core PB, the interior of the fixed core PC, and the opening in the upper wall portion VP1 of the joint portion VP of the valve body VB. As described above, the rod portion RP is attached to the movable core PB of the solenoid PS and can move vertically in conjunction with the vertical movement of the movable core PB of the solenoid PS. As shown in FIGS. 5 and 10, the base portion SQ1 of the plate member SQ is attached to the upper end of the rod portion RP. As shown in FIGS. 5 and 10, a male thread portion RPa is formed on the outer circumferential surface of the lower end of the rod portion RP. The male thread portion RPa is threadedly engaged with the female thread portion of the female thread forming member VR of the valve body VB, thereby attaching the valve body VB to the lower end of the rod portion RP (more specifically, to the lower portion of the bottom wall portion PA4 of the frame PA of the solenoid PS).

[0043] (3-5-3) Valve body The valve disc VB is used to open and close the pressure adjustment port ID1a in the valve seat forming member ID of the inner lid IL, and as shown in Figures 4 and 5, is disposed between the bottom wall portion PA4 of the frame PA of the solenoid PS and the base portion ID1 of the valve seat forming member ID of the inner lid IL. As shown in Figures 5 and 10, the valve disc VB is mainly composed of a valve main body portion VO, a joint portion VP, a packing member VQ, and a female thread forming member VR. These components will be described in detail below.

[0044] As shown in Figures 5 and 10, the valve body VO is mainly composed of a base portion VO1, an extension portion VO2, and the like. As shown in Figure 10, the base portion VO1 has a generally disk shape. As shown in Figures 5 and 10, the extension portions VO2 extend upward from six equally spaced locations on the circumference of the center of the base portion VO1. That is, the extension portion VO2 has a cylindrical shape with six equally spaced cutouts cut from the top to the bottom. As shown in Figure 5, a female thread-forming member VR is disposed inside the extension portion VO2.

[0045] As shown in Figures 5 and 10, the joint portion VP is located above the valve body portion VO and is mainly composed of an upper wall portion VP1, an inner wall portion VP2, a lower wall portion VP3, and an outer wall portion VP4. As shown in Figures 5 and 10, the upper wall portion VP1 has a generally annular shape with an opening in its center. As described above, the rod portion RP passes through this opening. As shown in Figures 5 and 10, the inner wall portion VP2 has a generally cylindrical shape and extends downward from the outer end of the upper wall portion VP1. The lower end of the inner wall portion VP2 is joined to the base portion VO1 of the valve body portion VO by welding, such as ultrasonic welding. As shown in Figures 5 and 10, the lower wall portion VP3 has a generally annular shape and extends outward from the vertical center of the inner wall portion VP2. As shown in Figures 5 and 10, the outer wall portion VP4 has a generally cylindrical shape and extends downward from the outer end of the lower wall portion VP3. As shown in Figure 5, the inner wall portion VP2, the lower wall portion VP3, and the outer wall portion VP4 form a recess, into which the fitting portion VQ5 of the packing member VQ is fitted.

[0046] As shown in FIGS. 5 and 10, the packing member VQ is mainly composed of a clamped portion VQ1, an outer wall portion VQ2, an inner wall portion VQ3, a lower wall portion VQ4, a fitting portion VQ5, and a deformation portion VQ6. As shown in FIGS. 5 and 10, the clamped portion VQ1 has a generally annular shape. As shown in FIG. 5, the clamped portion VQ1 is disposed between the bottom wall portion PA4 of the frame PA of the solenoid PS and the upper wall portion LE1 of the lower exterior member LE of the exterior body 141, and is sandwiched between these walls. The outer wall portion VQ2 has a generally cylindrical shape and extends downward from the inner end of the clamped portion VQ1, as shown in FIG. 5. The inner wall portion VQ3 has a generally cylindrical shape and is located outside the outer wall portion VP4 of the joint portion VP, as shown in FIG. 5. The lower wall portion VQ4 has a generally annular shape and extends inward from the lower end of the inner wall portion VQ3, as shown in FIG. 5. The lower wall portion VQ4 is sandwiched between the base portion VO1 of the valve body portion VO and the outer wall portion VP4 of the joint portion VP, as shown in FIG. 5. The fitting portion VQ5 has a generally cylindrical shape and extends upward from the outer end of the lower wall portion VQ4, as shown in FIG. 5. As described above, the fitting portion VQ5 is fitted into the recess formed by the inner wall portion VP2, the lower wall portion VP3, and the outer wall portion VP4 of the joint portion VP. The deformation portion VQ6 has a generally annular shape and extends from the lower end of the outer wall portion VQ2 to the upper end of the inner wall portion VQ3, as shown in FIG. 5. The deformation portion VQ6 is an elastically deformable portion and elastically deforms in response to the vertical movement of the movable iron core PB of the solenoid PS.

[0047] The female thread-forming member VR is, for example, a hexagonal nut. An internal thread is formed on the inner peripheral surface of the female thread-forming member VR, which is threadable with the male thread portion RPa of the rod portion RP. As shown in FIG. 5, the female thread-forming member VR is disposed between the base portion VO1 of the valve body portion VO and the upper wall portion VP1 of the joint portion VP, inside the extension portion VO2 of the valve body portion VO and inside the inner wall portion VP2 of the joint portion VP, and is embraced by the joint portion VP.

[0048] (3-5-4) Support member The support member SP is detachably attached to the lower exterior member LE of the exterior body 141. As shown in Fig. 5, when the support member SP is attached to the lower exterior member LE of the exterior body 141, the frame PA of the solenoid PS is sandwiched between the support member SP and the sandwiched portion VQ1 of the packing member VQ of the valve body VB. This supports the solenoid PS.

[0049] (3-5-5) Plate member The plate member SQ is a member that moves up and down in accordance with the up and down movement of the movable iron core PB of the solenoid PS, and is mainly formed of a base portion SQ1, an extension portion SQ2, etc. As shown in Figures 5, 7, 8, and 10, the base portion SQ1 is formed of a rectangular portion having a generally rectangular shape extending in the left-right direction, and a square portion having a generally square shape extending forward from the right side of the front end of the rectangular portion.

[0050] (3-5-6) Operation of the pressure adjustment mechanism The operation of the pressure adjustment mechanism 143 will now be described. First, to pressurize the interior of the inner pot 130, the microcomputer MC on the microcomputer board CB energizes the coil PD of the solenoid PS. This causes the movable core PB of the solenoid PS to move downward toward the fixed core PC of the solenoid PS against the biasing force of the coil spring PE, and the rod portion RP attached to the movable core PB of the solenoid PS also moves downward. At this time, the deformation portion VQ6 of the packing member VQ of the valve disc VB elastically deforms, and the valve body portion VO of the valve disc VB, the joint portion VP, the female thread-forming member VR, the inner wall portion VQ3 of the packing member VQ, the lower wall portion VQ4, and the fitting portion VQ5 also move downward. The valve body portion VO of the valve disc VB then abuts against the upper end of the valve seat portion ID2 of the valve seat-forming member ID of the inner lid IL, closing the pressure adjustment port ID1a of the valve seat-forming member ID. In this way, the inside of the inner pot 130 is pressurized.

[0051] When the interior of the inner pot 130 is not pressurized, the microcomputer MC on the microcomputer circuit board CB cuts off current to the coil PD of the solenoid PS. This causes the movable core PB of the solenoid PS to move upward (away from the fixed core PC) due to the biasing force of the coil spring PE, and the rod portion RP also moves upward. At this time, the deformation portion VQ6 of the packing member VQ of the valve disc VB elastically deforms, and the valve body portion VO of the valve disc VB, the joint portion VP, the female thread-forming member VR, the inner wall portion VQ3 of the packing member VQ, the lower wall portion VQ4, and the fitting portion VQ5 also move upward. The valve body portion VO of the valve disc VB then separates from the upper end of the valve seat ID2 of the valve seat-forming member ID of the inner lid IL, opening the pressure adjustment port ID1a of the valve seat-forming member ID. In this state, the interior of the inner pot 130 is not pressurized.

[0052] (3-6) Flow path forming section The flow path forming portion 144 forms a flow path within the lid 140 and, as described above, is attached to the upper end of the surrounding wall portion LE5 of the lower exterior member LE of the exterior body 141. Also, as shown in FIGS. 1 and 4, an exhaust port BO is formed in the flow path forming portion 144. As described above, the portion of the flow path forming portion 144 that forms the exhaust port BO is exposed from the third opening of the upper exterior member UE of the exterior body 141. Steam generated in the inner pot 130 passes through the opening ID1b in the valve seat forming member ID of the inner lid IL, then through the opening LE1d in the upper wall portion LE1 of the lower exterior member LE of the exterior body 141, and into the space formed by the upper wall portion LE1 of the lower exterior member LE of the exterior body 141, the surrounding wall portion LE5, and the flow path forming portion 144. The steam is then discharged to the outside of the lid 140 through the exhaust port BO.

[0053] (3-7) Lid locking mechanism 1, 2 and 4, the lid locking mechanism 145 is made up of an inner lid lever LL, a coil spring (not shown), etc. These components will be described in detail below.

[0054] (3-7-1) Inner lid lever The inner lid lever LL is a member that can be locked to the locking portion IB4 of the inner lid ring IB of the inner lid IL, and as described above, is located in the opening LE1b of the upper wall portion LE1 of the lower exterior member LE of the exterior body 141. One end of a coil spring is attached to the inner lid lever LL, and the inner lid lever LL is biased rearward by the coil spring. If an attempt is made to close the lid body 140 when the inner lid IL is not attached to the lid body 140 (when the inner lid lever LL is not locked to the locking portion IB4 of the inner lid ring IB of the inner lid IL), the inner lid lever LL comes into contact with the flange portion 133 of the inner pot 130, preventing the lid body 140 from being closed. The rear end of the inner lid lever LL has an inclined surface that slopes forward as it extends upward. As shown in Figure 4, when the inner lid IL is attached to the lid body 140 (in other words, when the inner lid lever LL is locked to the locked portion IB4 of the inner lid ring IB of the inner lid IL), this inclined surface abuts against the inclined surface of the locked portion IB4 of the inner lid ring IB of the inner lid IL. In addition, a guide groove is formed in the rear end of the inner lid lever LL, below the inclined surface. When the inner lid lever LL is locked to the locked portion IB4 of the inner lid ring IB of the inner lid IL, the rib IB5 of the inner lid ring IB of the inner lid IL passes through this guide groove while abutting against the front wall of the guide groove.

[0055] (3-7-2) Coil spring The coil spring biases the inner lid lever LL rearward and is disposed between the front wall of the spring mounting surface forming wall portion LE7 of the lower exterior member LE of the exterior body 141 and the inner lid lever LL. As described above, one end of the coil spring is attached to the rear surface of the front wall of the spring mounting surface forming wall portion LE7 of the lower exterior member LE of the exterior body 141, and the other end of the coil spring is attached to the inner lid lever LL. When the inner lid lever LL is engaged with the locking portion IB4 of the inner lid ring IB of the inner lid IL (see FIG. 4), the coil spring biases the inner lid lever LL rearward (in other words, toward the center of gravity of the inner lid IL or the locking portion IB4 of the inner lid ring IB of the inner lid IL as viewed from the inner lid lever LL), thereby biasing the inner lid IL rearward via the inner lid lever LL. This minimizes play between the locking portion IB4 of the inner lid ring IB of the inner lid IL and the rear end of the side wall portion LE2 of the lower exterior member LE of the exterior body 141. In addition, when the inner lid lever LL is engaged with the engaging portion IB4 of the inner lid ring IB of the inner lid IL, the inner lid IL is also forced upward via the inner lid lever LL due to the inclination of the inclined surface at the rear end of the inner lid lever LL that abuts against the inner lid ring IB of the inner lid IL.

[0056] (3-8) Inner lid As shown in Figures 1 and 4, when the inner lid IL is attached to the lid 140, it is located below the upper wall portion LE1 and inside the side wall portion LE2 of the lower exterior member LE of the exterior body 141. Also, as shown in Figure 1, when the lid 140 is closed with the inner lid IL attached to it, the inner lid IL covers the top of the inner pot 130, sealing the inside of the inner pot 130. Also, as shown in Figures 2 and 4 to 6, the inner lid IL is mainly composed of an inner lid main body IA, an inner lid ring IB, a packing IC, and a valve seat-forming member ID. These components are described in detail below.

[0057] (3-8-1) Inner lid body As shown in FIGS. 2, 4, and 6, the inner lid main body IA is primarily formed of a lower wall portion IA1, an inner wall portion IA2, an upper wall portion IA3, and an outer wall portion IA4. As shown in FIG. 2, the lower wall portion IA1 has a generally disk-like shape when viewed from the bottom. As shown in FIGS. 2, 4, and 5, a downwardly recessed recess IA1a is formed in the center of the lower wall portion IA1. As shown in FIGS. 4 to 6, a valve seat-forming member ID is disposed within the recess IA1a. As shown in FIGS. 2, 4, and 5, an opening IA1b is formed in the front portion of the bottom wall of the recess IA1a, into which the lower end of the valve seat portion ID2 of the valve seat-forming member ID is fitted. As shown in FIGS. 2 and 4, an opening IA1c is formed in the rear portion of the bottom wall of the recess IA1a, into which the cylindrical wall portion ID3 of the valve seat-forming member ID is fitted. As shown in Figures 4 and 6, the inner wall portion IA2 extends upward from the outer end of the lower wall portion IA1 and has a generally cylindrical shape. As shown in Figures 4 and 6, the upper wall portion IA3 extends outward from the upper end of the inner wall portion IA2 and has a generally annular shape. The outer wall portion IA4 has a generally cylindrical shape and extends downward from the outer end of the upper wall portion IA3 as shown in Figure 4. Furthermore, when the inner lid main body IA is attached to the inner lid ring IB, the outer wall portion IA4 is located inside the outer groove on the upper surface of the base portion IB1 of the inner lid ring IB.

[0058] (3-8-2) Inner lid ring As shown in Figures 2, 4, and 6, the inner cover ring IB is composed of a base portion IB1, a supported portion IB2, a handle portion IB3, a locked portion IB4, and a rib IB5. As shown in Figure 6, the base portion IB1 has a generally annular shape. An outer groove is formed circumferentially on the upper surface of the base portion IB1, and an inner groove is formed circumferentially on the upper surface of the base portion IB1, located inside the outer groove in a plan view. After the packing IC is attached to the inner cover ring IB so that the outer wall portion of the packing IC is positioned inside the inner groove, the inner cover main body IA is attached to the inner cover ring IB so that the outer wall portion IA4 of the inner cover main body IA is positioned inside the outer groove. As shown in Figures 2, 4, and 6, the supported portion IB2 extends rearward from the rear end of the base portion IB1. As shown in Figures 2 and 6, the handle portion IB3 extends outward from the left and right sides of the front end of the base portion IB1. A user of the rice cooker 100 can grasp the handle portion IB3 when removing the inner lid IL from the lid body 140. As shown in Figures 2 and 6, the locking portion IB4 extends forward from the front end and center in the left-right direction of the base portion IB1. Note that a sloped surface that slopes forward as it extends upward is formed on the part of the locking portion IB4 below the rib IB5. As shown in Figure 6, the rib IB5 extends forward from the front end and center in the left-right direction of the base portion IB1, and is formed between the right end wall portion and the left end wall portion of the locking portion IB4, and is formed above the sloped surface of the locking portion IB4.

[0059] (3-8-3) Packing The packing IC is a member made of a flexible material and is mainly composed of an inner wall portion IC1 (see FIG. 6), an upper flange portion, an outer wall portion, and a lower flange portion. The inner wall portion IC1 has a generally cylindrical shape (see FIG. 6). The upper flange portion has a generally annular shape and extends outward from the upper end of the inner wall portion IC1. The outer wall portion has a generally cylindrical shape and extends downward from the outer end of the upper flange portion. As described above, when the packing IC is attached to the inner cover ring IB, the outer wall portion is located inside the inner groove of the base portion IB1 of the inner cover ring IB. The lower flange portion has a generally annular shape and extends outward from the vertical center of the inner wall portion IC1. As shown in FIG. 1, when the lid body 140 is in the closed state, the lower flange abuts against the flange portion 133 of the inner pot 130, closing the gap between the inner pot 130 and the inner lid IL.

[0060] (3-8-4) Valve seat forming member As shown in FIGS. 4 to 6, the valve seat-forming member ID is composed of a base portion ID1, a valve seat portion ID2, and a cylindrical wall portion ID3. The base portion ID1 has a generally elliptical shape in a plan view. As shown in FIGS. 2 and 4 to 6, a pressure adjustment port ID1a is formed in the front of the base portion ID1, and an opening ID1b is formed in the rear of the base portion ID1. The valve seat portion ID2 has a generally cylindrical shape and extends vertically from the edge of the pressure adjustment port ID1a of the base portion ID1, as shown in FIGS. 4 to 6. The lower end of the valve seat portion ID2 is fitted into the opening IA1b of the inner lid main body IA, as described above. The cylindrical wall portion ID3 has a generally cylindrical shape and extends downward from the edge of the opening ID1b of the base portion ID1, as shown in FIG. 4. The cylindrical wall portion ID3 is fitted into the opening IA1c of the inner lid main body IA, as described above.

[0061] Here, we will explain how to attach the inner lid IL to the lid body 140. First, the supported portion IB2 of the inner lid ring IB of the inner lid IL is inserted into the gap LE4a between the upper wall portion LE1 and the support portion LE4 of the lower exterior member LE of the exterior body 141, and the rib IB5 of the inner lid ring IB of the inner lid IL is inserted into the guide groove of the inner lid lever LL. Then, by pushing the front part of the inner lid IL upward, the rib IB5 of the inner lid ring IB of the inner lid IL moves upward through the guide groove of the inner lid lever LL while abutting against the front wall surface of the guide groove of the inner lid lever LL. At this time, the inner lid lever LL moves forward against the biasing force of the coil spring. When the front of the inner lid IL is further pushed upward, the rib IB5 of the inner lid ring IB of the inner lid IL passes through the guide groove of the inner lid lever LL and is positioned above the rear end of the inner lid lever LL, and the inclined surface of the locking portion IB4 of the inner lid ring IB of the inner lid IL comes into contact with the inclined surface of the rear end of the inner lid lever LL. As a result, the inner lid lever LL is locked to the locking portion IB4 of the inner lid ring IB of the inner lid IL, and the inner lid IL is attached to the lid body 140.

[0062] Next, we will explain how to remove the inner lid IL from the lid body 140. First, for example, by pressing the inner lid lever LL forward with the pad of a finger, the inner lid lever LL is moved forward against the biasing force of the coil spring. This releases the inner lid lever LL from its state of being locked to the locked portion IB4 of the inner lid ring IB of the inner lid IL. Then, for example, by gripping the handle portion IB3 of the inner lid ring IB of the inner lid IL, the front of the inner lid IL is moved downward to the inner lid lever LL. Then, the supported portion IB2 of the inner lid ring IB of the inner lid IL is pulled out from the gap LE4a between the upper wall portion LE1 and the support portion LE4 of the lower exterior member LE of the exterior body 141, and the inner lid IL is removed from the lid body 140.

[0063] (3-9) Reinforcement member Reinforcing member 146 is intended to increase the rigidity of exterior body 141, and is formed from, for example, sheet metal such as hot-dip galvanized steel sheet (SGCC), or engineering plastic such as polyphenylene sulfide (PPS).

[0064] (3-10) Steam sensor The steam sensor is a temperature sensor for measuring the temperature inside the lid 140 , more specifically, the temperature of the steam flowing through the flow path inside the lid 140 .

[0065] (3-11) Opening and closing mechanism The opening / closing mechanism 147 is a mechanism that controls the opening and closing of the lid body 140, and as shown in Figures 1 and 4, is mainly composed of an operating part OA, a coil spring OB, a lever member OC, an opening / closing mechanism side pivot axis OD, an opening / closing mechanism side torsion spring (not shown), and a pressing member OE.

[0066] <Pressure control function in the rice cooker according to the embodiment of the present invention> As described above, in the rice cooker 100 according to an embodiment of the present invention, when the interior space of the inner pot 130 is pressurized, the lid 140 is closed and the movable core PB and rod portion RP of the solenoid PS move downward. This applies a load to the valve body VO, closing the interior space of the inner pot 130. As shown in FIG. 11, the rice cooker 100 returns the interior space of the inner pot 130, which is in a pressurized state (1.25 atmospheres), to atmospheric pressure (1.05 atmospheres) through steps S101 to S103 according to the set air pressure. Below, we will explain, with reference to FIG. 11, the pressure control function of the rice cooker 100 that prevents blowing noise from being generated from the exhaust port BO of the rice cooker 100 when the interior space of the inner pot is returned from a pressurized state (1.25 atmospheres) to atmospheric pressure (1.05 atmospheres). First, a first pressure reduction control is executed to reduce the pressure in the inner space of the inner pot 130, which is in a pressurized state (1.25 atmospheres) (step S101), to a first set pressure (1.10 atmospheres) (step S102). In the first pressure reduction control, a "first duty output control that generates a first pressing force on the valve body VO" and a "second duty output control that generates a second pressing force lower than the first pressing force on the valve body VO" are alternately executed on the valve body VO. Specifically, while maintaining the ON ratio of the first duty output at 100%, the ON ratio of the second duty output is reduced by 1% for each control of the second duty output. Then, when the ON ratio of the second duty output reaches 34% or a certain time has elapsed since the start of the first pressure reduction control, the process transitions to a second pressure reduction control that reduces the pressure from the first set pressure (1.10 atmospheres) to atmospheric pressure (1.05 atmospheres) (step S103). During the second pressure reduction control, the first duty output control and the second duty output control are alternately performed on the valve body VO. Specifically, while the ON ratio of the first duty output is maintained at 100%, the ON ratio of the second duty output is reduced by 1% for each control of the second duty output. Then, when the ON ratio of the second duty output reaches 34% or a certain amount of time has elapsed since the start of the second pressure reduction control, the ON ratio of the first duty output is reduced to 90%. This returns the pressure in the internal space of the inner pot 130 to atmospheric pressure (1.05 atm).

[0067] Furthermore, in the rice cooker 100 according to an embodiment of the present invention, if the ON ratio of the second duty output does not reach 34% during execution of the first pressure reduction control and a certain period of time elapses before transitioning to the second pressure reduction control, the ON ratio of the second duty output in the first pressure reduction control ("45%" in Figure 12) is carried over as the ON ratio of the second duty output in the second pressure reduction control ("44%" in Figure 12) (step S104), and the second pressure reduction control is executed.

[0068] <Features of the rice cooker according to the embodiment of the present invention> (1) In the rice cooker 100 according to the embodiment of the present invention, multiple pressure reduction controls are provided according to the set air pressure, and when the pressurized internal space of the inner pot 130 of the rice cooker 100 is returned to atmospheric pressure, a first pressure reduction control is carried out first. Then, after a certain time has passed since the first pressure reduction control, the next pressure reduction control, a second pressure reduction control, is carried out, thereby gradually returning the pressure in the internal space of the inner pot 130 to atmospheric pressure. As a result, in this rice cooker 100, it is possible to prevent loud blowing noises from being generated from the exhaust port BO.

[0069] (2) In the rice cooker 100 according to the embodiment of the present invention, even if the ON ratio of the second duty output in the first pressure reduction control has not reached the second specific ON ratio and the rice cooker transitions to the second pressure reduction control after a certain time has elapsed, the ON ratio of the second duty output in the first pressure reduction control is carried over as the ON ratio of the second duty output in the second pressure reduction control. The second pressure reduction control is then executed from the ON ratio of the second duty output that has been carried over. This allows the pressure in the internal space of the inner pot 130 of the rice cooker 100 to be returned to atmospheric pressure through multi-stage pressure reduction control, preventing loud blowing noise from being generated from the exhaust port BO.

[0070] <Modification> (A) In the above embodiment, the present invention is applied to the rice cooker 100, but the present invention may also be applied to cooking appliances, devices, etc. other than rice cookers that perform pressure adjustment.

[0071] (B) In the rice cooker 100 according to the previous embodiment, the pressure in the internal space of the inner pot 130, which is in a pressurized state (1.25 atmospheres) (step S101) (see Figure 11), is reduced to a first set pressure (1.10 atmospheres) (step S102) (see Figure 11), and after a certain period of time has elapsed, the pressure in the internal space of the inner pot 130 is reduced from the first set pressure (1.10 atmospheres) to atmospheric pressure (1.05 atmospheres) (step S103) (see Figure 11), thereby returning the pressure in the internal space of the inner pot 130 to atmospheric pressure (1.05 atmospheres). However, in the rice cooker 100, the pressure in the internal space of the inner pot 130, which is in a pressurized state (1.25 atmospheres) (step S105) (see Figure 13), may also be reduced to atmospheric pressure (1.05 atmospheres) (step S106) (see Figure 13), thereby returning the pressure in the internal space of the inner pot 130 to atmospheric pressure (1.05 atmospheres). In this case, the first duty output control and the second duty output control are alternately executed on the valve main body VO. Specifically, while the ON ratio of the first duty output is maintained at 100%, the ON ratio of the second duty output is reduced by 1% for each control of the second duty output. Then, after the ON ratio of the second duty output reaches 37%, the ON ratio of the first duty output is reduced to 90% (see FIG. 13).

[0072] (C) In the rice cooker 100 according to the previous embodiment, the ON ratio of the second duty output was reduced in 1% increments from 57% to 34%, but in the rice cooker 100, when reducing the ON ratio of the second duty output from 57% to 34%, the ON ratio of the second duty output may be reduced in 3% increments or 5% increments from 57%. This value can be set appropriately during the design stage of the rice cooker 100.

[0073] (D) In the rice cooker 100 according to the previous embodiment, the ON ratio of the first duty output is reduced to 90% after the ON ratio of the second duty output reaches 34%, but in the rice cooker 100, when reducing the ON ratio of the first duty output from 100% to 90%, the ON ratio of the first duty output may be reduced from 100% in 1% or 5% increments, for example. This value can be set appropriately during the design stage of the rice cooker 100.

[0074] (E) In the rice cooker 100 according to the previous embodiment, the pressurized internal space of the inner pot 130 of the rice cooker 100 was returned to atmospheric pressure by the first pressure reduction control and the second pressure reduction control, but in addition to the first set pressure, a second set pressure and a third set pressure, etc. may be added as appropriate during the design stage of the rice cooker 100. In such a case, in addition to the first pressure reduction control and the second pressure reduction control, a third pressure reduction control that reduces the pressure in the internal space of the inner pot 130 from the first set pressure to the second set pressure, or a fourth pressure reduction control that reduces the pressure in the internal space of the inner pot 130 from the second set pressure to the third set pressure, etc. may also be provided, and multi-stage pressure reduction control functions can be added as appropriate during the design stage of the rice cooker 100.

[0075] (F) In the rice cooker 100 according to the previous embodiment, if the ON ratio of the second duty output in the first pressure reduction control did not reach 34% and a certain period of time elapsed before transitioning to the second pressure reduction control, the ON ratio of the second duty output in the first pressure reduction control ("45%" in Figure 12) was carried over as the ON ratio of the second duty output in the second pressure reduction control ("44%" in Figure 12), and the second pressure reduction control was executed. However, the value of the ON ratio of the second duty output in the first pressure reduction control ("45%" in Figure 14) may also be carried over as the ON ratio of the second duty output in the second pressure reduction control ("45%" in Figure 14) (step S107), and the second pressure reduction control may be executed.

[0076] The above modified examples may be applied individually or in combination. [Explanation of symbols]

[0077] 100 Rice cooker (cooking appliance) 113 Induction heating coil (heating part) 130 Inner pot 143 Pressure adjustment mechanism (valve mechanism control unit) ID2 Valve seat part PS solenoid (valve mechanism) VB valve body VO valve body

Claims

1. The inner pot and A heating unit that heats the inner pot; a valve mechanism that opens and closes a communication passage that connects the internal space of the inner pot with the external space using a valve seat; a valve seat provided for the valve body; a valve mechanism control unit that controls the pressing force of the valve element against the valve seat; Equipped with The valve mechanism control unit alternately controls the valve element by "controlling a first output to generate a first pressing force on the valve element against the valve seat" and "controlling a second output to generate a second pressing force on the valve element against the valve seat, the second pressing force being lower than the first pressing force." When returning the internal space of the inner pot to atmospheric pressure, the valve mechanism control unit lowers the ON ratio of the second output by a constant value for each control of the second output, and after the ON ratio of the second output reaches a second specific ON ratio, performs a first pressure reduction control to lower the ON ratio of the first output to a first specific ON ratio. Cooker.

2. When the ON ratio of the second output in the first pressure reduction control does not reach a second specific ON ratio and the control transitions to a second pressure reduction control that is a next pressure reduction control, the ON ratio of the second output in the first pressure reduction control is carried over as the ON ratio of the second output in the second pressure reduction control. The cooking device according to claim 1 .

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